To the Editor:Podocytic infolding glomerulopathy (PIG)was proposed as a new disease entity in 2008,[1] and great attention has been paid to PIG because of the rare pathological changes to glomeruli associated with it....To the Editor:Podocytic infolding glomerulopathy (PIG)was proposed as a new disease entity in 2008,[1] and great attention has been paid to PIG because of the rare pathological changes to glomeruli associated with it.PIG is characterized by specific changes to the thickened glomerular basement membrane (GBM), including microspheres,microtubular structures,and podocytic infolding.However,the clinical features and pathogenesis of PIG still remain unclear.To elucidate the characteristics of this glomerulopathy,accumulating more information from reported cases is necessary.Herein,we present a case of glomerulopathy showing podocytic infolding in association with primary Sjogren's syndrome (pSS)and Hashimoto's thyroiditis.展开更多
The underlying molecular changes that result in minimal change disease(ne-phrotic syndrome)require an in-depth analysis.Current molecular studies have shown the involvement of zinc fingers and homeobox transcriptional...The underlying molecular changes that result in minimal change disease(ne-phrotic syndrome)require an in-depth analysis.Current molecular studies have shown the involvement of zinc fingers and homeobox transcriptional factors in its pathogenesis.The application of therapeutic drugs relies on understanding the cascade of molecular events to determine their efficacy in managing the clinical condition.展开更多
Objectives:Podocytes undergo epithelial-mesenchymal transition(EMT)and ferroptosis in response to hyperglycemic stimulation.This is considered an important early event in the development and progression of diabetic ne...Objectives:Podocytes undergo epithelial-mesenchymal transition(EMT)and ferroptosis in response to hyperglycemic stimulation.This is considered an important early event in the development and progression of diabetic nephropathy(DN).Rhein is the main active anthraquinone derivative in several common traditional herbal medicines.This study aimed to investigate the protective effects of Rhein on podocyte ferroptosis and EMT.Methods:The mouse glomerular podocyte cell line MPC5 was stimulated with high glucose(HG),Rhein,and the ferroptosis inhibitor ferrostatin-1(Fer-1).Mechanistic investigations employed plasmids to overexpress and knockdown Sirtuin-1(SIRT1),solute carrier family 7 member 11(SLC7A11),or p53 and measure ferroptosis-or EMT-related indicators.Results:In the HG-injured podocytes,Rhein enhanced cell viability,reduced malondialdehyde(MDA),ferrous iron(Fe2+),and reactive oxygen species(ROS)levels,increased glutathione(GSH)production,accompanied by the restoration of ferroptosis-and EMT-associated indicator expressions.Mechanistically,Rhein induced SIRT1 and SLC7A11 expression and attenuated p53 expression.SIRT1 knockdown upregulated p53 and downregulated SLC7A11,thereby abolishing the protective effects of Rhein against podocyte ferroptosis and EMT.However,the effects of SIRT1 overexpression were reversed by SLC7A11 knockdown.Conclusion:Rhein activated the SIRT1/p53/SLC7A11 axis to protect podocytes against ferroptosis and EMT.This suggests that Rhein has a potential therapeutic effect on DN patients associated with podocyte injury,and targeting SIRT1/p53/SLC7A11 may represent an innovative therapeutic strategy for DN patients.展开更多
BACKGROUND Diabetic nephropathy(DN)is a leading cause of chronic kidney disease and endstage renal disease,and is a significant global healthcare burden.Although proximal tubular epithelial cells(PTECs)and podocytes a...BACKGROUND Diabetic nephropathy(DN)is a leading cause of chronic kidney disease and endstage renal disease,and is a significant global healthcare burden.Although proximal tubular epithelial cells(PTECs)and podocytes are involved in DN progression,the specific molecular interactions between these cells are not well understood.AIM To elucidate the role of interleukin-6(IL-6)/Rab5 signaling in mediating crosstalk between PTECs and podocytes,and to evaluate the protective effects of nicotinamide mononucleotide(NMN)against DN progression.METHODS We utilized in vitro and in vivo models to investigate the pathogenesis of DN.In vitro,human PTECs and murine podocytes were cultured under high-glucose conditions,and IL-6 neutralizing antibodies or NMN treatments were applied.Podocyte injury was assessed by measurements of nephrin endocytosis,Rab5 activity,cytoskeletal organization,cell adhesion,and cell-spreading assays.In vivo,DN was induced in mice using streptozotocin,and mice then received NMN,insulin,or both treatments over an 8-week period.Renal tissues were analyzed histologically,ultrastructurally,and immunochemically,and urinary albumin excretion was measured to assess renal function.Statistical analyses were conducted using one-way ANOVA and Tukey's test.RESULTS High-glucose conditions induced the epithelial-mesenchymal transition(EMT)in PTECs,increased IL-6 secretion,and activated Rab5 signaling in podocytes,leading to increased nephrin endocytosis and podocyte injury.Blocking IL-6 significantly attenuated these effects.NMN treatment of diabetic mice markedly reduced podocyte injury,glomerular hypertrophy,foot-process effacement,and urinary albumin excretion.Mechanistically,NMN suppressed the EMT and IL-6 secretion by PTECs,inhibited Rab5 activation in podocytes,and prevented nephrin endocytosis,thereby preserving the cytoskeletal integrity and function of podocytes.CONCLUSION Our findings reveal a novel pathogenic mechanism of DN in which IL-6 released from glucose-stressed PTECs activates Rab5 signaling in podocytes,followed by nephrin endocytosis and structural injury of podocytes.Importantly,NMN treatment effectively disrupted this pathological pathway of intercellular communication,and provided significant protection against DN progression.These results suggest that NMN supplementation and targeting the IL-6/Rab5 signaling axis has promise as a therapeutic strategy for managing DN.展开更多
The present study was designed to determine the mechanism underlying the treatment of nephrotic syndrome using astragaloside by observing the effects of astragaloside on the expression of nephrin and podocin proteins ...The present study was designed to determine the mechanism underlying the treatment of nephrotic syndrome using astragaloside by observing the effects of astragaloside on the expression of nephrin and podocin proteins and genes in kidneys of rats with adriamycin nephropathy.The rats were injected with adriamycin and,after successful model establishment,randomly divided into a model group,a Methylprednisolone(MP)group,and an astragaloside group.The 24-h complete urine samples were collected.Biochemical indicators were monitored,and kidney tissues were collected for pathological analysis using light microscopy and electron microscopy.The m RNA expression of nephrin and podocin was measured in the kidney tissues using the real-time q PCR,and the protein expression levels of nephrin and podocin were detected using Western blot analysis.At the end of 12 weeks of drug intervention,the urinary protein level was lower in the MP and astragaloside groups than that in the model group(P=0.008 and P=0.01,respectively).Serum albumin was higher in the MP and astragaloside groups than in the model group(P<0.001 and P=0.012,respectively).Podocytes in the MP group were nearly normal,and fusion of podocytes in the astragaloside group was significantly less than that in the control group.The nephrin and podocin m RNA and protein expression levels in the intervention groups were higher(P<0.05)than that in the model group.Due to the increased expression of podocyte-related nephrin and podocin proteins,astragaloside maintained slit diaphragm integrity and decreased the level of proteinuria in rats with adriamycin nephropathy.展开更多
OBJECTIVE:To investigate the effects of Tongluo Digui decoction on renal injury and streptozotocin-induced podocyte autophagy in diabetic rats.METHODS:Male Sprague-Dawley rats were randomly divided into six groups:nor...OBJECTIVE:To investigate the effects of Tongluo Digui decoction on renal injury and streptozotocin-induced podocyte autophagy in diabetic rats.METHODS:Male Sprague-Dawley rats were randomly divided into six groups:normal,model,Tongluo Digui decoction(high,medium,and low dose)and valsartan.Streptozotocin was injected intraperitoneally to replicate the diabetic animal model.After 8 weeks,proteinuria was evaluated to establish the diabetic nephropathy model.Treatments were administered daily via the intragastric route.At 16 weeks after gavage,we determined 24 h urine protein concentration,and blood glucose,serum creatinine,and urea nitrogen concentrations.Then,rats were sacrificed,and kidneys were harvested and stained with periodic acid-Schiff to evaluate the pathological changes in glomeruli,including glomerular podocytes by transmission electron microscopy.Western blot analysis was used to determine the expression of nephrin,podocin,p62,beclin-1,LC3Ⅱ/Ⅰ,and p-m TOR/m TOR protein in kidney tissues.RESULTS:Compared with the model group,Tongluo Digui decoction was associated with decreases in 24 h urine protein concentration,and blood glucose,hemoglobin A1 c,serum creatinine,urea nitrogen concentrations,total serum protein and albumin.Concurrently,mesangial mesenteric broadening and fusion of foot processes were reduced,the glomerular basement membrane was not significantly thickened,and the number of podocytes and the number of autophagosomes in the podocytes was increased.Further,expression of nephrin,podocin,LC3Ⅱ,and beclin-1 protein in kidney tissue was up-regulated,while expression of p62 protein was down-regulated and m TOR phosphorylation was inhibited.CONCLUSION:Tongluo Digui decoction may inhibit the progression of diabetic nephropathy by inhibiting m TOR phosphorylation,thereby increasing autophagy to protect podocytes and reducing proteinuria.展开更多
This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy （AN）. A total of 36 healthy male SD rats were randomly assigned to three groups： control group, AN group and sulod...This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy （AN）. A total of 36 healthy male SD rats were randomly assigned to three groups： control group, AN group and sulodexide treatment group. Rat models of AN were established by a single tail intravenous injection of adriamycin （6.5 mg/kg） in both AN group and sulodexide treatment group. Sulodexide （10 mg/kg） was administered the rats in the treatment group once daily by garage from the first day of model establishment until the 14th day or the 28th day. Samples of 24-h urine and renal cortex tissues were harvested at day 14, 28 after the model establishment. Excretion of 24-h urinary protein was measured by Coomassie brilliant blue method. The pathological changes in renal tissues were observed by light microscopy and electron microscopy respectively. Heparanase mRNA was detected by RT-PCR. Expressions of desmin, CD2AP and heparanase were determined by immunohistological staining. The results showed that the expressions of heparanase mRNA and protein were increased in the glomeruli of AN rats at day 14 and 28 after the model establishment, which was accompanied by the increased expression of desmin and CD2AP. The mRNA and protein expression of heparanase was decreased in the sulodexide-treated rats as compared with AN rats at day 14 and 28. And, the protein expression of desmin and CD2AP was reduced as with heparanase in the sulodexide-treated rats. Proteinuria and podocyte foot process effacement were alleviated in the AN rats after sulodexide treatment. There was a positive correlation between the expression of heparanase and the expression of desmin and CD2AP （as well as 24-h urinary protein excretion）. It was concluded that increased heparanase is involved in podocyte injury. Sulodexide can maintain and restore podocyte morphology by inhibiting the expression of heparanase in AN.展开更多
Eukaryotic expression vectors carrying the small hairpin RNA （shRNA） for TRPC6 mRNA were constructed, and the effects of knocking-down TRPC6 on puromycin aminonucleoside （PAN）-induced apoptosis of mouse podocytes ...Eukaryotic expression vectors carrying the small hairpin RNA （shRNA） for TRPC6 mRNA were constructed, and the effects of knocking-down TRPC6 on puromycin aminonucleoside （PAN）-induced apoptosis of mouse podocytes were observed. Two eukaryotic expression vectors containing small hairpin structure targeting TRPC6 named pGCsi-TRPC6A and pGCsi-TRPC6B were designed and synthesized. The plasmids were transfected into conditionally immortalized murine podocyte cell line by liposome. The changes in the TRPC6 mRNA and protein expression were observed by RT-PCR and Western blot after 48 h. Cultured podocytes were divided into four groups： control group, PAN treatment group, PAN treatment＋shRNA transfection group, and PAN treatment＋negative control group. The expression of Bax and Bcl-2 mRNA and proteins was detected by RT-PCR and Western-blot respectively. The apoptotic rate of podocytes was measured by flow cytometry. The results showed that the expression of TRPC6 mRNA and protein was decreased in the podocytes when transfected with pGCsi-TRPC6A, and pGCsi-TRPC6B. The expression of Bax was increased, and that of Bcl-2 was decreased at protein and mRNA levels in the podocytes after treated with PAN for 48 h. These changes was attenuated by knocking-down TRPC6. Knocking-down TRPC6 could effectively decrease the PAN-induced apoptosis of podocytes. It was concluded that TRPC6 may play an important role in the PAN-induced apoptosis of podocytes. Knocking-down TRPC6 gene could effectively prevent the podocytes from apoptosis induced by PAN.展开更多
BACKGROUND Modern guidelines recommend sodium-glucose cotransporter-2(SGLT2)inhibitors as the preferred antihyperglycemic agents for patients with type 2 diabetes and chronic kidney disease.However,the mechanisms unde...BACKGROUND Modern guidelines recommend sodium-glucose cotransporter-2(SGLT2)inhibitors as the preferred antihyperglycemic agents for patients with type 2 diabetes and chronic kidney disease.However,the mechanisms underlying the renal protective effect of SGLT2 inhibitors are not fully understood.structure of podocytes and nephrin expression in glomeruli in db/db diabetic mice.METHODS We treated 8-wk-old male db/db mice with EMPA(10 mg/kg/d)or vehicle for 8 wk.Age-matched male db/+mice were included as non-diabetic controls.Parameters of body composition,glycemic and lipid control,and plasma concentrations of leptin,insulin and glucagon were assessed.We evaluated renal hypertrophy as kidney weight adjusted to lean mass,renal function as plasma levels of creatinine,and albuminuria as the urinary albumin-to-creatinine ratio(UACR).Renal structures were studied by light and transmission electron microscopy with a focus on mesangial volume and podocyte structure,respectively.Glomerular nephrin and transforming growth factor beta(TGF-β)were assessed by immunohistochemistry.RESULTS Severe obesity and hyperglycemia developed in db/db mice prior to the start of the experiment;increased plasma concentrations of fructosamine,glycated albumin,cholesterol,leptin,and insulin,and elevated UACR were detected.Mesangial expansion,glomerular basement membrane thickening,and increased area of TGF-βstaining in glomeruli were revealed in vehicle-treated mice.Podocytopathy was manifested by effacement of foot processes;nephrin-positive areas in glomeruli were reduced.EMPA decreased the levels of glucose,fructosamine and glycated albumin,UACR,kidney hypertrophy,mesangial expansion,glomerular basement membrane thickening,and glomerular TGF-βstaining,alleviated podocytopathy and restored glomerular staining of nephrin.CONCLUSION These data indicate that EMPA attenuates podocytopathy in experimental diabetic kidney disease.The anti-albuminuric effect of EMPA could be attributed to mitigation of podocyte injury and enhancement of nephrin expression.展开更多
OBJECTIVE:To investigate the therapeutic action and mechanism of the Qizhi Jiangtang capsule(芪蛭降糖胶囊,QZJT)on diabetic kidney disease(DKD)treatment.METHODS:This experiment used db/db mice and podocytes(MPC5)to dev...OBJECTIVE:To investigate the therapeutic action and mechanism of the Qizhi Jiangtang capsule(芪蛭降糖胶囊,QZJT)on diabetic kidney disease(DKD)treatment.METHODS:This experiment used db/db mice and podocytes(MPC5)to develop DKD model.Evaluation of the effect of the QZJT on db/db mice by testing urine and blood biochemical parameters(24-h urinary albumin,serum creatinine,blood urine nitrogen),pathological kidney injury,and podocyte integrity.Moreover,autophagosomes in podocytes of DKD mice and cultured podocytes were detected using electron microscopy.Additionally,Western blotting was applied to detect the expression of podocyte marker protein(podocin),autophagy-associated proteins,and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)signaling pathway changes in vivo and in vitro.RESULTS:QZJT significantly reduced urine protein,blood nitrogen urea,and serum creatinine and showed histological restoration of renal tissues.QZJT also significantly improved the down-regulation of podocin and foot fusion and effacement in db/db mice.QZJT increased autophagic vesicles in mice and cultured podocytes.QZJT also upregulated microtubuleassociated protein 1 light chain 3-II(LC3-II)/(LC3-I)and Beclin-1 and downregulated phosphorylated-PI3K(pPI3K),p-AKT,and p-mTOR in db/db mice and MPC5 cells.However,autophagy inhibitor 3-methyladenine partially alleviated the above effects in MPC5 cells.CONCLUSIONS:These results showed that the QZJT can enhance podocyte autophagy and ameliorate podocyte injury in DKD by inhibiting the PI3K/AKT/mTOR signaling pathway.展开更多
This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA （shRNA） targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside （PAN）-induced ...This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA （shRNA） targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside （PAN）-induced podocyte injury. Two DNA sequences containing the small hairpin structure targeting TRPC6 were designed, synthesized and then inserted into the green fluorescence protein （GFP）-contained plasmids （pGC） to establish the plasmids pGCsi-TRPC6A and pGCsi-TRPC6B. Plasmids expressing scrambled shRNA were used as negative control and named pGCsi-NC. These plasmids were transfected into a conditionally immortalized murine podocyte cell line by using liposome. Flow cytometry was used to examine the transfection efficiency. TRPC6 mRNA and protein ex-pression levels were detected by RT-PCR and Western blotting. Cultured podocytes were divided into four groups： control group, PAN treatment group, PAN＋TRPC6 shRNA transfected group and PAN＋scrambled shRNA transfected group. The paracelluar permeability to BSA was evaluated by Millicell-PCF Inserts and cell viability was measured by the trypan blue assay. Immunofluorescent assay was used to observe the distribution of α-actinin-4 and α-tubulin. The results showed that the transfection efficiency of the shRNA expression vector was about 45%. Expression levels of TRPC6 mRNA and protein were downregulated after transfection with pGCsi-TRPC6A and pGCsi-TRPC6B. Knocking down TRPC6 gene could effectively reverse the PAN-induced increase in the paracelluar permeability to BSA. The distribution of α-actinin-4 and α-tubulin was disrupted after treatment with PAN, which was reversed by knocking down TRPC6 gene. It was concluded that knocking down TRPC6 gene could effectively prevent podocytes from the permeability increase induced by PAN, which may be related to the regulation of podocyte cytoskeleton.展开更多
BACKGROUND Hypertension is prevalent in the general population and is regarded as the second leading cause of renal damage and dysfunction,outnumbered only by diabetes.However,the mechanisms remain unclear.AIM To inve...BACKGROUND Hypertension is prevalent in the general population and is regarded as the second leading cause of renal damage and dysfunction,outnumbered only by diabetes.However,the mechanisms remain unclear.AIM To investigate podocyte injury induced by hypertension in the early course without massive proteinuria or renal dysfunction.METHODS The hypertension group comprised 18 patients with hypertension accompanied by microalbuminuria,diagnosed with hypertensive renal injury according to biopsy results.For a comparison of pathological changes in renal tissue,control group 1 comprised 10 healthy volunteers,and control group 2 comprised 16 patients who underwent surgery for renal trauma.RESULTS The hypertension group had significantly higher blood pressure(P=0.000)and microalbuminuria(P=0.000)compared with control group 1.In the hypertension group,urinary podocytes were detected following positive staining of podocytespecific nephrin and/or CD2-associated protein(CD2AP)in urine sediment.Podocyte foot process fusion and a significant decrease in nephrin and/or CD2AP expression in glomeruli were observed in the hypertension group compared with control group 2.This indicated that hypertension caused podocyte injury and detachment from the glomerular basement membrane,which was consistent with urinary detection of podocytes.CONCLUSION Our results suggest that podocyturia appears early in the course of hypertensive renal injury,and may be a sensitive marker for early prediction of hypertensive renal injury.展开更多
Objective:Diabetic nephropathy is one of the most important microvascular complications of diabetes,which mainly refers to glomerular capillary sclerosis.Podocytes are an important part of glomerular capillaries.Previ...Objective:Diabetic nephropathy is one of the most important microvascular complications of diabetes,which mainly refers to glomerular capillary sclerosis.Podocytes are an important part of glomerular capillaries.Previous clinical and basic studies have shown that fibrosis is the main factor of diabetic nephropathy.This study aimed to assess the protective mechanism of glycyrrhizic acid(GA)on glomerular podocytes induced by high glucose as we hypothesized that GA may have antifibrotic and anti-inflammatory effects on podocytes through regulation of the adenosine 5'-monophosphate-activated protein kinase(AMPK)/sucrose nonfermenting AMPK-related kinase(SNARK)signaling pathway.Methods:SNARK siRNA was used to transfect podocytes.Real-time quantitative polymerase chain reaction and immunofluorescence staining assays were used for molecular and pathological analysis.The expression levels of key pathway proteins(including TGF-β1,α-SMA,SITR1,AMPKα,LKB1,PGC-1α,NF-κB,IL-6,and TNF-α)were verified by Western blotting.The expression of inflammatory factors in podocytes was detected by ELISA.Results:We demonstrated that GA decreased the expression of podocyte fibrosis signaling pathway-related factors by upregulating the AMPK pathway and its related factors.However,after transfection of podocytes with SNARK siRNA,there was an increased expression of fibrosis-related factors and inflammation-related factors.Conclusion:GA can protect podocytes and alleviate fibrosis and inflammation induced by high glucose,which is related to the AMPK signaling pathway.Meanwhile,knockdown of SNARK protein can inhibit the AMPK signaling pathway,aggravate fibrosis,and increase inflammation.展开更多
Objective： To observe the podocyte injury in diabetic nephropathy （DN） patients by identifying the urinary podocytes and the situation of detached podocytes in glomeruli and to demonstrate the correlation between p...Objective： To observe the podocyte injury in diabetic nephropathy （DN） patients by identifying the urinary podocytes and the situation of detached podocytes in glomeruli and to demonstrate the correlation between podocyte excretion and proteinuria, blood glucose, serum creatinine in different phases in DN patients. Methods： Urinary podocytes and the podocalyxin （PCX） expression state of podocytes in glomeruli were identified and observed by indirect immunofluorescent method. The DN patients were divided into three groups according to the volume of proteinuria, namely small, medium and large volume proteinuria groups. The podocytes in the urine of every group were calculated. The DN patients were divided into five groups according to the chronic kidney disease （CKD） phases, then the positive podocytes in urine were calculated. Meanwhile, the 24-hour protein in urine, fasting blood glucose （FBG） and the serum creatinine of DN patients were tested. The correlations among the proteinuria, serum creatinine, FBG and the number of positive podocytes in the urine of DN patients were statistically analyzed. Results： Urinary positive podocytes were found in 88% of the patients with DN, whereas podocytes were found in 0% of patients with minimal changed disease （MCD） and healthy cases. The expression of PCX was absent in DN patients. In contrast, PCX was expressed integrally in MCD patients. The positive podocytes was 1.49±0.95/ml in small-volume proteinuria group, 2.15±0.70/ml in the medium-volume proteinuria group, and 3.48±1.27/ml in the large-volume proteinuria group. There was no significant difference between the small- and medium- volume proteinuria groups, and there were significant differences between other groups （P〈0.05）. The positive podocyte number tended to increase as proteinuria was increased. By Pearson analysis, the correlation between podocyte number and proteinuria was podocytes in urine from different groups of DN patients, CKD pc I sitive statistically. The difference of the number of positive -V group was significant statistically. The correlation between serum creatinine of CKD Ⅰ -Ⅲ group and positive podocytes in urine was positive statistically. The correlation between serumcreatinine of CKD Ⅳ- Ⅴ group and positive podocytes in urine was not significant statistically. The correlation between FBG and positive podocytes in urine was not significant either. Conclusion： The mechanism of the podocyte injury in DN patients is present. The podocyte injury in DN may positively correlate to proteinuria and serum creatinine of CKD Ⅰ -ⅢDN patients, but not to the FBG and serum creatinine of CKD Ⅳ-Ⅴ patients.展开更多
The slit diaphragm bridging the neighboring foot pro-cesses functions as a fnal barrier of glomerular capil-lary wall for preventing the leak of plasma proteins into primary urine. It is now accepted that the dysfunct...The slit diaphragm bridging the neighboring foot pro-cesses functions as a fnal barrier of glomerular capil-lary wall for preventing the leak of plasma proteins into primary urine. It is now accepted that the dysfunction of the sit diaphragm contributes to the development of proteinuria in several glomerular diseases. Neph-rin, a gene product of NPHS1, a gene for a congenital nephrotic syndrome of Finnish type, constitutes an ex-tracellular domain of the slit diaphragm. Podocin was identified as a gene product of NPHS2 , a gene for a familial steroid-resistant nephrotic syndrome of French. Podocin binds the cytoplasmic domain of nephrin. After then, CD2 associated protein, NEPH1 and transient re-ceptor potential-6 were also found as crucial molecules of the slit diaphragm. In order to explore other novel molecules contributing to the development of protein-uria, we performed a subtraction hybridization assay with a normal rat glomerular RNA and a glomerular RNA of rats with a puromycin aminonucleoside ne-phropathy, a mimic of a human minimal change type nephrotic syndrome. Then we have found that synaptic vesicle protein 2B, ephrin-B1 and neurexin were already downregulated at the early stage of puromycin aminonucleoside nephropathy, and that these molecules were localized close to nephrin. It is conceivable that these molecules are the slit diaphragm associated molecules, which participate in the regulation of the barrier func-tion. These molecules could be targets to establish a novel therapy for nephrotic syndrome.展开更多
OBJECTIVE: To observe the effects and mechanisms of Bushenhuoxue on desmin and nephrin expression in mice podocytes, and to investigate its effects on wt1 expression in Wilms' tumor.METHODS: Adriamycin(ADR) was us...OBJECTIVE: To observe the effects and mechanisms of Bushenhuoxue on desmin and nephrin expression in mice podocytes, and to investigate its effects on wt1 expression in Wilms' tumor.METHODS: Adriamycin(ADR) was used to induce focal segmental glomerulous sclerosis(FSGS) in mice. Bushenhuoxue was used to treat FSGS for 6 weeks. We measured body mass and right renal mass, and determined serum albumin(ALB) levels,protein content in urine, and urinary protein and albumin creatinine ratio(UACR). Changes in renal tissue morphology were evaluated by microscopy.wt1 and nephrin expression in podocytes were detected using immunofluorescence. Expression levels of desmin, wt1 and nephrin m RNAs in renal tissue were determined using reverse transcription polymerase chain reaction assays.RESULTS: Protein levels in urine and UACR were significantly increased in FSGS model mice compared with Bushenhuoxue-treated and control mice.Body mass and ALB levels were decreased in FSGS mice compared with control and Bushenhuoxue-treated mice. Expression of the wt1 protein was observed in control mice. Compared with controls,wt1 expression levels were reduced in Bushenhuoxue-treated mice, and to a greater extent in FSGS mice. Nephrin protein expression was widespread in FSGS mice, and significantly reduced in control and Bushenhuoxue mice. Expression levels of wt1 and nephrin m RNAs in FSGS mice were lower compared with those in control and Bushenhuoxue-treated mice. Desmin m RNA levels in FSGS mice were reduced compared with those in control and Bushenhuoxue-treated mice.CONCLUSION: Bushenhuoxue ameliorated albuminuria in FSGS mice; this was possibly related to the up-regulation of wt1 and nephrin, and down-regulation of desmin.展开更多
To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved,36 male Sprague-Dawley rats were randomly divided into control group,adriamycin nephropathy...To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved,36 male Sprague-Dawley rats were randomly divided into control group,adriamycin nephropathy（AN） group and eplerenone-treated group（100 mg.kg-1.d-1 eplerenone）.Blood pressure,24-h urinary protein,serum potassium,sodium and creatinine were measured 28 days after adriamycin injection（a single tail intravenous injection of 6.5 mg/kg adriamycin）.The morphological changes of renal tissues were observed by light and electron microscopy.Immunohistochemistry and Western blotting were performed to examine the expression of TGF-β1 and desmin in renal cortex.The results showed that 28 days after adriamycin injection,there were no significant changes in the level of serum potassium,sodium,creatinine concentrations and blood pressure values in the rats of the three groups.Meanwhile,the 24-h proteinuria excretion in the AN group was significantly higher than that in the control group（P0.01）,but that in the eplerenone-treated group was substantially reduced when compared with that in the AN group（P0.05）.Mild mesangial cell proliferation and matrix expansion,diffuse deformation and confluence of foot processes in podocytes were found in the AN group.By contrast,rats in the eplerenone-treated group exhibited obvious attenuation of these morphological lesions.The protein expression of TGF-β1 and desmin in the AN group was markedly up-regulated in contrast to that in the control group（P0.01）,whereas that in the eplerenone-treated group was much lower than in the AN group（P0.05）.It was concluded that eplerenone may ameliorate the proteinuria and the development of pathological alteration in adriamycin-induced nephropathy presumably via the inhibition of cytokine release,and restore the morphology of podocytes independent of its blood pressure-lowing effects.展开更多
BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of DN.Studies have shown that corilagin(...BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of DN.Studies have shown that corilagin(Cor)has hepatoprotective,anti-inflammatory,antibacterial,antioxidant,anti-hypertensive,antidiabetic,and anti-tumor activities.AIM To explore the protective effect of Cor against podocyte injury in DN mice and the underlying mechanisms.METHODS Streptozotocin and a high-fat diet were combined to generate DN mice models,which were then divided into either a Cor group or a DN group(n=8 in each group).Mice in the Cor group were intraperitoneally injected with Cor(30 mg/kg/d)for 12 wk,and mice in the DN group were treated with saline.Biochemical analysis was used to measure the blood lipid profiles.Hematoxylin and eosin staining was used to detect pathological changes in kidney tissue.Immunohistochemistry and Western blotting were used to assess the protein expression of nephrin and podocin.Mouse podocyte cells(MPC5)were cultured and treated with glucose(5 mmol/L),Cor(50μM),high glucose(HG)(30 mmol/L),and HG(30 mmol/L)plus Cor(50μM).Real-time quantitative PCR and Western blotting RESULTS Compared with the control group,the DN mice models had increased fasting blood glucose,glycosylated hemoglobin,triglycerides,and total cholesterol,decreased nephrin and podocin expression,increased apoptosis rate,elevated inflammatory cytokines,and enhanced oxidative stress.All of the conditions mentioned above were alleviated after intervention with Cor.In addition,Cor therapy improved SIRT1 and AMPK expression(P<0.001),inhibited reactive oxygen species and oxidative stress,and elevated autophagy in HG-induced podocytes(P<0.01).CONCLUSION Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway,thereby exerting its protective impact on renal function in DN mice.展开更多
BACKGROUND A number of recent studies indicate a transformation in the natural course of chronic kidney disease(CKD)in type 2 diabetes(T2D)patients:an increasing prevalence of declined renal function without proceedin...BACKGROUND A number of recent studies indicate a transformation in the natural course of chronic kidney disease(CKD)in type 2 diabetes(T2D)patients:an increasing prevalence of declined renal function without proceeding to the accompanying elevation of albuminuria.It has been suggested that albuminuric and nonalbuminuric CKD patterns could be different in their phenotypes and pathogenic mechanisms.AIM To identify the risk factors and biomarkers of albuminuric and non-albuminuric patterns of CKD in patients with T2D.METHODS Three hundred sixty patients with T2D duration≥10 years were included in this observational cross-sectional study.The associations of a panel of demographic and clinical characteristics,complications,comorbidities,and metabolic and hematology parameters with albuminuric and non-albuminuric CKD patterns were analyzed.The urinary excretion of nephrin and podocin,two podocytespecific markers,and WAP-four-disulfide core domain protein 2(WFDC-2),a marker of tubulointerstitial fibrosis,was determined by ELISA in comparison with healthy controls.RESULTS Non-albuminuric CKD was associated with age≥65 years(P=0.0001),female sex(P=0.04),diabetes duration≥15 years(P=0.0009),and the use of diuretics(P=0.0005).Male sex(P=0.01),smoking(P=0.01),waist-to-hip ratio>1.0(P=0.01)and hemoglobin A1c(HbA1c)>8.0%(P=0.005)were risk factors for elevated albuminuria not accompanied by a decrease in estimated glomerular filtration rate(eGFR).Duration of diabetes≥15 years and the use of calcium channel blockers were risk factors for albuminuria with decreased eGFR(both P=0.01).In multivariate logistic regression analysis,age,HbA1c,female sex and diuretics were significant predictors for reduced eGFR,while waist-to-hip ratio,HbA1c and male sex were associated with elevated urinary albumin-to-creatinine ratio(UACR).Excretion of nephrin and podocin was increased in patients with albuminuria,regardless of decline in renal function(P<0.001),correlating positively with UACR.The urinary excretion of WFDC-2 was markedly higher in men than in women(P<0.000001).Men with T2D demonstrated increased WFDC-2 levels independently of the CKD pattern(all P<0.05).In T2D women,WFDC-2 excretion was increased in those with reduced renal function(P≤0.01),correlating negatively with eGFR.CONCLUSION The data provide further evidence that albuminuric and non-albuminuric CKD phenotypes correspond to different pathways of diabetic kidney disease progression.展开更多
文摘To the Editor:Podocytic infolding glomerulopathy (PIG)was proposed as a new disease entity in 2008,[1] and great attention has been paid to PIG because of the rare pathological changes to glomeruli associated with it.PIG is characterized by specific changes to the thickened glomerular basement membrane (GBM), including microspheres,microtubular structures,and podocytic infolding.However,the clinical features and pathogenesis of PIG still remain unclear.To elucidate the characteristics of this glomerulopathy,accumulating more information from reported cases is necessary.Herein,we present a case of glomerulopathy showing podocytic infolding in association with primary Sjogren's syndrome (pSS)and Hashimoto's thyroiditis.
文摘The underlying molecular changes that result in minimal change disease(ne-phrotic syndrome)require an in-depth analysis.Current molecular studies have shown the involvement of zinc fingers and homeobox transcriptional factors in its pathogenesis.The application of therapeutic drugs relies on understanding the cascade of molecular events to determine their efficacy in managing the clinical condition.
基金supported by the Hunan Province Natural Science Foundation Medical Industry Joint Fund(No.2024JJ9421)Clinical Medical Technology Innovation Guide Project of Hunan Province(No.2021SK51418).
文摘Objectives:Podocytes undergo epithelial-mesenchymal transition(EMT)and ferroptosis in response to hyperglycemic stimulation.This is considered an important early event in the development and progression of diabetic nephropathy(DN).Rhein is the main active anthraquinone derivative in several common traditional herbal medicines.This study aimed to investigate the protective effects of Rhein on podocyte ferroptosis and EMT.Methods:The mouse glomerular podocyte cell line MPC5 was stimulated with high glucose(HG),Rhein,and the ferroptosis inhibitor ferrostatin-1(Fer-1).Mechanistic investigations employed plasmids to overexpress and knockdown Sirtuin-1(SIRT1),solute carrier family 7 member 11(SLC7A11),or p53 and measure ferroptosis-or EMT-related indicators.Results:In the HG-injured podocytes,Rhein enhanced cell viability,reduced malondialdehyde(MDA),ferrous iron(Fe2+),and reactive oxygen species(ROS)levels,increased glutathione(GSH)production,accompanied by the restoration of ferroptosis-and EMT-associated indicator expressions.Mechanistically,Rhein induced SIRT1 and SLC7A11 expression and attenuated p53 expression.SIRT1 knockdown upregulated p53 and downregulated SLC7A11,thereby abolishing the protective effects of Rhein against podocyte ferroptosis and EMT.However,the effects of SIRT1 overexpression were reversed by SLC7A11 knockdown.Conclusion:Rhein activated the SIRT1/p53/SLC7A11 axis to protect podocytes against ferroptosis and EMT.This suggests that Rhein has a potential therapeutic effect on DN patients associated with podocyte injury,and targeting SIRT1/p53/SLC7A11 may represent an innovative therapeutic strategy for DN patients.
基金Supported by Hubei Provincial Natural Science Foundation,No.2023AFB732and Scientific Research Project of Hubei Provincial Health Commission,No.WJ2023M053.
文摘BACKGROUND Diabetic nephropathy(DN)is a leading cause of chronic kidney disease and endstage renal disease,and is a significant global healthcare burden.Although proximal tubular epithelial cells(PTECs)and podocytes are involved in DN progression,the specific molecular interactions between these cells are not well understood.AIM To elucidate the role of interleukin-6(IL-6)/Rab5 signaling in mediating crosstalk between PTECs and podocytes,and to evaluate the protective effects of nicotinamide mononucleotide(NMN)against DN progression.METHODS We utilized in vitro and in vivo models to investigate the pathogenesis of DN.In vitro,human PTECs and murine podocytes were cultured under high-glucose conditions,and IL-6 neutralizing antibodies or NMN treatments were applied.Podocyte injury was assessed by measurements of nephrin endocytosis,Rab5 activity,cytoskeletal organization,cell adhesion,and cell-spreading assays.In vivo,DN was induced in mice using streptozotocin,and mice then received NMN,insulin,or both treatments over an 8-week period.Renal tissues were analyzed histologically,ultrastructurally,and immunochemically,and urinary albumin excretion was measured to assess renal function.Statistical analyses were conducted using one-way ANOVA and Tukey's test.RESULTS High-glucose conditions induced the epithelial-mesenchymal transition(EMT)in PTECs,increased IL-6 secretion,and activated Rab5 signaling in podocytes,leading to increased nephrin endocytosis and podocyte injury.Blocking IL-6 significantly attenuated these effects.NMN treatment of diabetic mice markedly reduced podocyte injury,glomerular hypertrophy,foot-process effacement,and urinary albumin excretion.Mechanistically,NMN suppressed the EMT and IL-6 secretion by PTECs,inhibited Rab5 activation in podocytes,and prevented nephrin endocytosis,thereby preserving the cytoskeletal integrity and function of podocytes.CONCLUSION Our findings reveal a novel pathogenic mechanism of DN in which IL-6 released from glucose-stressed PTECs activates Rab5 signaling in podocytes,followed by nephrin endocytosis and structural injury of podocytes.Importantly,NMN treatment effectively disrupted this pathological pathway of intercellular communication,and provided significant protection against DN progression.These results suggest that NMN supplementation and targeting the IL-6/Rab5 signaling axis has promise as a therapeutic strategy for managing DN.
基金supported by the National Sciences Foundation of China(Nos.81273968 and 81471027)Ministerial projects of the National Working Commission on Aging(QLB2014W002)the“Four Hundreds Project of 301 Hospital(YS201408)
文摘The present study was designed to determine the mechanism underlying the treatment of nephrotic syndrome using astragaloside by observing the effects of astragaloside on the expression of nephrin and podocin proteins and genes in kidneys of rats with adriamycin nephropathy.The rats were injected with adriamycin and,after successful model establishment,randomly divided into a model group,a Methylprednisolone(MP)group,and an astragaloside group.The 24-h complete urine samples were collected.Biochemical indicators were monitored,and kidney tissues were collected for pathological analysis using light microscopy and electron microscopy.The m RNA expression of nephrin and podocin was measured in the kidney tissues using the real-time q PCR,and the protein expression levels of nephrin and podocin were detected using Western blot analysis.At the end of 12 weeks of drug intervention,the urinary protein level was lower in the MP and astragaloside groups than that in the model group(P=0.008 and P=0.01,respectively).Serum albumin was higher in the MP and astragaloside groups than in the model group(P<0.001 and P=0.012,respectively).Podocytes in the MP group were nearly normal,and fusion of podocytes in the astragaloside group was significantly less than that in the control group.The nephrin and podocin m RNA and protein expression levels in the intervention groups were higher(P<0.05)than that in the model group.Due to the increased expression of podocyte-related nephrin and podocin proteins,astragaloside maintained slit diaphragm integrity and decreased the level of proteinuria in rats with adriamycin nephropathy.
基金Supported by the funds of Key Scientific Research Project of Colleges and Universities in Henan Province in 2017(Explore the Mechanism of Huoxue Tongluo Decoction in Preventing and Treating Diabetic Nephropathy from the Regulation of Podocyte Autophagy by Mtor Signal Pathway,No.17A360003)the Research Project of National TCM Clinical Research Base(Project Number:2019jdzx068+9 种基金Project Name:Study on the Effect of Tongluo Digui Decoction on Circadian Rhythm of Diabetic Nephropathy Based on Lncrna-mrna Chip Technology)the Special Research Project of TCM In Henan Province(Project Number:2019zybj17Project Name:Study on the Mechanism of Tongluo Digui Decoction in the Treatment of Diabetic Kidney Disease by Regulating the Pyroptosis of Podocyte through Autophagy-related Molecular Pathways)Henan Province Key R&D and Promotion Special(Science and Technology)Project(Project Number:202102310505Project Name:Study on the Mechanism Of Tongluo Digui Decoction in the Treatment of Diabetic Nephropathy Based on Autophagy Regulating Renal Tubular Epithelial Cell Pyroptosis)Henan Province Key R&D and Promotion Special(Science and Technology)Project(Project Number:202102310171Project Name:to Explore the Mechanism of Tongluo Digui Decoction on Improving Non-dipper Blood Pressure In Diabetic Nephropathy Based on Circadian Rhythm)a Sub-station Project of the Inheritance Studio of Famous Old Chinese Medicine Experts Across the CountryTCM Top Talent Training Project of Henan ProvinceNational TCM Innovational Core Talent Training Project。
文摘OBJECTIVE:To investigate the effects of Tongluo Digui decoction on renal injury and streptozotocin-induced podocyte autophagy in diabetic rats.METHODS:Male Sprague-Dawley rats were randomly divided into six groups:normal,model,Tongluo Digui decoction(high,medium,and low dose)and valsartan.Streptozotocin was injected intraperitoneally to replicate the diabetic animal model.After 8 weeks,proteinuria was evaluated to establish the diabetic nephropathy model.Treatments were administered daily via the intragastric route.At 16 weeks after gavage,we determined 24 h urine protein concentration,and blood glucose,serum creatinine,and urea nitrogen concentrations.Then,rats were sacrificed,and kidneys were harvested and stained with periodic acid-Schiff to evaluate the pathological changes in glomeruli,including glomerular podocytes by transmission electron microscopy.Western blot analysis was used to determine the expression of nephrin,podocin,p62,beclin-1,LC3Ⅱ/Ⅰ,and p-m TOR/m TOR protein in kidney tissues.RESULTS:Compared with the model group,Tongluo Digui decoction was associated with decreases in 24 h urine protein concentration,and blood glucose,hemoglobin A1 c,serum creatinine,urea nitrogen concentrations,total serum protein and albumin.Concurrently,mesangial mesenteric broadening and fusion of foot processes were reduced,the glomerular basement membrane was not significantly thickened,and the number of podocytes and the number of autophagosomes in the podocytes was increased.Further,expression of nephrin,podocin,LC3Ⅱ,and beclin-1 protein in kidney tissue was up-regulated,while expression of p62 protein was down-regulated and m TOR phosphorylation was inhibited.CONCLUSION:Tongluo Digui decoction may inhibit the progression of diabetic nephropathy by inhibiting m TOR phosphorylation,thereby increasing autophagy to protect podocytes and reducing proteinuria.
基金supported by a grant from the National Natural Sciences Foundation of China (No 30500245)
文摘This study examined the effect of sulodexide on podocyte injury in rats with adriamycin nephropathy （AN）. A total of 36 healthy male SD rats were randomly assigned to three groups： control group, AN group and sulodexide treatment group. Rat models of AN were established by a single tail intravenous injection of adriamycin （6.5 mg/kg） in both AN group and sulodexide treatment group. Sulodexide （10 mg/kg） was administered the rats in the treatment group once daily by garage from the first day of model establishment until the 14th day or the 28th day. Samples of 24-h urine and renal cortex tissues were harvested at day 14, 28 after the model establishment. Excretion of 24-h urinary protein was measured by Coomassie brilliant blue method. The pathological changes in renal tissues were observed by light microscopy and electron microscopy respectively. Heparanase mRNA was detected by RT-PCR. Expressions of desmin, CD2AP and heparanase were determined by immunohistological staining. The results showed that the expressions of heparanase mRNA and protein were increased in the glomeruli of AN rats at day 14 and 28 after the model establishment, which was accompanied by the increased expression of desmin and CD2AP. The mRNA and protein expression of heparanase was decreased in the sulodexide-treated rats as compared with AN rats at day 14 and 28. And, the protein expression of desmin and CD2AP was reduced as with heparanase in the sulodexide-treated rats. Proteinuria and podocyte foot process effacement were alleviated in the AN rats after sulodexide treatment. There was a positive correlation between the expression of heparanase and the expression of desmin and CD2AP （as well as 24-h urinary protein excretion）. It was concluded that increased heparanase is involved in podocyte injury. Sulodexide can maintain and restore podocyte morphology by inhibiting the expression of heparanase in AN.
基金supported by grants from the NationalNatural Science Foundation of China(No.30500245 and No.30871174)the Science Research Foundation of HealthDepartment of Hubei Province(No.NX200510)
文摘Eukaryotic expression vectors carrying the small hairpin RNA （shRNA） for TRPC6 mRNA were constructed, and the effects of knocking-down TRPC6 on puromycin aminonucleoside （PAN）-induced apoptosis of mouse podocytes were observed. Two eukaryotic expression vectors containing small hairpin structure targeting TRPC6 named pGCsi-TRPC6A and pGCsi-TRPC6B were designed and synthesized. The plasmids were transfected into conditionally immortalized murine podocyte cell line by liposome. The changes in the TRPC6 mRNA and protein expression were observed by RT-PCR and Western blot after 48 h. Cultured podocytes were divided into four groups： control group, PAN treatment group, PAN treatment＋shRNA transfection group, and PAN treatment＋negative control group. The expression of Bax and Bcl-2 mRNA and proteins was detected by RT-PCR and Western-blot respectively. The apoptotic rate of podocytes was measured by flow cytometry. The results showed that the expression of TRPC6 mRNA and protein was decreased in the podocytes when transfected with pGCsi-TRPC6A, and pGCsi-TRPC6B. The expression of Bax was increased, and that of Bcl-2 was decreased at protein and mRNA levels in the podocytes after treated with PAN for 48 h. These changes was attenuated by knocking-down TRPC6. Knocking-down TRPC6 could effectively decrease the PAN-induced apoptosis of podocytes. It was concluded that TRPC6 may play an important role in the PAN-induced apoptosis of podocytes. Knocking-down TRPC6 gene could effectively prevent the podocytes from apoptosis induced by PAN.
基金Supported by Ministry of Science and Higher Education of Russia(the budget projects No.0324-2019-0045/0324-2019-0045-C-02,grant No.RFMEFI62119X0023)Boehringer Ingelheim Pharma。
文摘BACKGROUND Modern guidelines recommend sodium-glucose cotransporter-2(SGLT2)inhibitors as the preferred antihyperglycemic agents for patients with type 2 diabetes and chronic kidney disease.However,the mechanisms underlying the renal protective effect of SGLT2 inhibitors are not fully understood.structure of podocytes and nephrin expression in glomeruli in db/db diabetic mice.METHODS We treated 8-wk-old male db/db mice with EMPA(10 mg/kg/d)or vehicle for 8 wk.Age-matched male db/+mice were included as non-diabetic controls.Parameters of body composition,glycemic and lipid control,and plasma concentrations of leptin,insulin and glucagon were assessed.We evaluated renal hypertrophy as kidney weight adjusted to lean mass,renal function as plasma levels of creatinine,and albuminuria as the urinary albumin-to-creatinine ratio(UACR).Renal structures were studied by light and transmission electron microscopy with a focus on mesangial volume and podocyte structure,respectively.Glomerular nephrin and transforming growth factor beta(TGF-β)were assessed by immunohistochemistry.RESULTS Severe obesity and hyperglycemia developed in db/db mice prior to the start of the experiment;increased plasma concentrations of fructosamine,glycated albumin,cholesterol,leptin,and insulin,and elevated UACR were detected.Mesangial expansion,glomerular basement membrane thickening,and increased area of TGF-βstaining in glomeruli were revealed in vehicle-treated mice.Podocytopathy was manifested by effacement of foot processes;nephrin-positive areas in glomeruli were reduced.EMPA decreased the levels of glucose,fructosamine and glycated albumin,UACR,kidney hypertrophy,mesangial expansion,glomerular basement membrane thickening,and glomerular TGF-βstaining,alleviated podocytopathy and restored glomerular staining of nephrin.CONCLUSION These data indicate that EMPA attenuates podocytopathy in experimental diabetic kidney disease.The anti-albuminuric effect of EMPA could be attributed to mitigation of podocyte injury and enhancement of nephrin expression.
基金National Natural Science Foundation of China Project:Experimental Research on Podocyte Autophagy of Diabetic Nephropathy Regulated by Qizhi Jiangtang Capusul(No.81874440)Natural Science Foundation of Shandong Province Project:Curcumin Ameliorates Diabetic Nephropathy via Regulating the Intestinal Barrier-Inflammation“cross-talk”(ZR2020QH063)。
文摘OBJECTIVE:To investigate the therapeutic action and mechanism of the Qizhi Jiangtang capsule(芪蛭降糖胶囊,QZJT)on diabetic kidney disease(DKD)treatment.METHODS:This experiment used db/db mice and podocytes(MPC5)to develop DKD model.Evaluation of the effect of the QZJT on db/db mice by testing urine and blood biochemical parameters(24-h urinary albumin,serum creatinine,blood urine nitrogen),pathological kidney injury,and podocyte integrity.Moreover,autophagosomes in podocytes of DKD mice and cultured podocytes were detected using electron microscopy.Additionally,Western blotting was applied to detect the expression of podocyte marker protein(podocin),autophagy-associated proteins,and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin(PI3K/AKT/mTOR)signaling pathway changes in vivo and in vitro.RESULTS:QZJT significantly reduced urine protein,blood nitrogen urea,and serum creatinine and showed histological restoration of renal tissues.QZJT also significantly improved the down-regulation of podocin and foot fusion and effacement in db/db mice.QZJT increased autophagic vesicles in mice and cultured podocytes.QZJT also upregulated microtubuleassociated protein 1 light chain 3-II(LC3-II)/(LC3-I)and Beclin-1 and downregulated phosphorylated-PI3K(pPI3K),p-AKT,and p-mTOR in db/db mice and MPC5 cells.However,autophagy inhibitor 3-methyladenine partially alleviated the above effects in MPC5 cells.CONCLUSIONS:These results showed that the QZJT can enhance podocyte autophagy and ameliorate podocyte injury in DKD by inhibiting the PI3K/AKT/mTOR signaling pathway.
基金supported by grants from the National Natural Science Foundation of China(No.31050110433,No.81170600 and No.81170662)
文摘This study was aimed to construct eukaryotic expression vectors carrying the small hairpin RNA （shRNA） targeting TRPC6 gene and investigate the effect of TRPC6 knockdown on puromucin aminonucleoside （PAN）-induced podocyte injury. Two DNA sequences containing the small hairpin structure targeting TRPC6 were designed, synthesized and then inserted into the green fluorescence protein （GFP）-contained plasmids （pGC） to establish the plasmids pGCsi-TRPC6A and pGCsi-TRPC6B. Plasmids expressing scrambled shRNA were used as negative control and named pGCsi-NC. These plasmids were transfected into a conditionally immortalized murine podocyte cell line by using liposome. Flow cytometry was used to examine the transfection efficiency. TRPC6 mRNA and protein ex-pression levels were detected by RT-PCR and Western blotting. Cultured podocytes were divided into four groups： control group, PAN treatment group, PAN＋TRPC6 shRNA transfected group and PAN＋scrambled shRNA transfected group. The paracelluar permeability to BSA was evaluated by Millicell-PCF Inserts and cell viability was measured by the trypan blue assay. Immunofluorescent assay was used to observe the distribution of α-actinin-4 and α-tubulin. The results showed that the transfection efficiency of the shRNA expression vector was about 45%. Expression levels of TRPC6 mRNA and protein were downregulated after transfection with pGCsi-TRPC6A and pGCsi-TRPC6B. Knocking down TRPC6 gene could effectively reverse the PAN-induced increase in the paracelluar permeability to BSA. The distribution of α-actinin-4 and α-tubulin was disrupted after treatment with PAN, which was reversed by knocking down TRPC6 gene. It was concluded that knocking down TRPC6 gene could effectively prevent podocytes from the permeability increase induced by PAN, which may be related to the regulation of podocyte cytoskeleton.
基金Supported by the Natural Science Foundation of Liaoning Provincial Department of Science and Technology,No.2017225020
文摘BACKGROUND Hypertension is prevalent in the general population and is regarded as the second leading cause of renal damage and dysfunction,outnumbered only by diabetes.However,the mechanisms remain unclear.AIM To investigate podocyte injury induced by hypertension in the early course without massive proteinuria or renal dysfunction.METHODS The hypertension group comprised 18 patients with hypertension accompanied by microalbuminuria,diagnosed with hypertensive renal injury according to biopsy results.For a comparison of pathological changes in renal tissue,control group 1 comprised 10 healthy volunteers,and control group 2 comprised 16 patients who underwent surgery for renal trauma.RESULTS The hypertension group had significantly higher blood pressure(P=0.000)and microalbuminuria(P=0.000)compared with control group 1.In the hypertension group,urinary podocytes were detected following positive staining of podocytespecific nephrin and/or CD2-associated protein(CD2AP)in urine sediment.Podocyte foot process fusion and a significant decrease in nephrin and/or CD2AP expression in glomeruli were observed in the hypertension group compared with control group 2.This indicated that hypertension caused podocyte injury and detachment from the glomerular basement membrane,which was consistent with urinary detection of podocytes.CONCLUSION Our results suggest that podocyturia appears early in the course of hypertensive renal injury,and may be a sensitive marker for early prediction of hypertensive renal injury.
基金supported by the Natural Science Foundation of Ningxia Province(No.2021AAC03296).
文摘Objective:Diabetic nephropathy is one of the most important microvascular complications of diabetes,which mainly refers to glomerular capillary sclerosis.Podocytes are an important part of glomerular capillaries.Previous clinical and basic studies have shown that fibrosis is the main factor of diabetic nephropathy.This study aimed to assess the protective mechanism of glycyrrhizic acid(GA)on glomerular podocytes induced by high glucose as we hypothesized that GA may have antifibrotic and anti-inflammatory effects on podocytes through regulation of the adenosine 5'-monophosphate-activated protein kinase(AMPK)/sucrose nonfermenting AMPK-related kinase(SNARK)signaling pathway.Methods:SNARK siRNA was used to transfect podocytes.Real-time quantitative polymerase chain reaction and immunofluorescence staining assays were used for molecular and pathological analysis.The expression levels of key pathway proteins(including TGF-β1,α-SMA,SITR1,AMPKα,LKB1,PGC-1α,NF-κB,IL-6,and TNF-α)were verified by Western blotting.The expression of inflammatory factors in podocytes was detected by ELISA.Results:We demonstrated that GA decreased the expression of podocyte fibrosis signaling pathway-related factors by upregulating the AMPK pathway and its related factors.However,after transfection of podocytes with SNARK siRNA,there was an increased expression of fibrosis-related factors and inflammation-related factors.Conclusion:GA can protect podocytes and alleviate fibrosis and inflammation induced by high glucose,which is related to the AMPK signaling pathway.Meanwhile,knockdown of SNARK protein can inhibit the AMPK signaling pathway,aggravate fibrosis,and increase inflammation.
文摘Objective： To observe the podocyte injury in diabetic nephropathy （DN） patients by identifying the urinary podocytes and the situation of detached podocytes in glomeruli and to demonstrate the correlation between podocyte excretion and proteinuria, blood glucose, serum creatinine in different phases in DN patients. Methods： Urinary podocytes and the podocalyxin （PCX） expression state of podocytes in glomeruli were identified and observed by indirect immunofluorescent method. The DN patients were divided into three groups according to the volume of proteinuria, namely small, medium and large volume proteinuria groups. The podocytes in the urine of every group were calculated. The DN patients were divided into five groups according to the chronic kidney disease （CKD） phases, then the positive podocytes in urine were calculated. Meanwhile, the 24-hour protein in urine, fasting blood glucose （FBG） and the serum creatinine of DN patients were tested. The correlations among the proteinuria, serum creatinine, FBG and the number of positive podocytes in the urine of DN patients were statistically analyzed. Results： Urinary positive podocytes were found in 88% of the patients with DN, whereas podocytes were found in 0% of patients with minimal changed disease （MCD） and healthy cases. The expression of PCX was absent in DN patients. In contrast, PCX was expressed integrally in MCD patients. The positive podocytes was 1.49±0.95/ml in small-volume proteinuria group, 2.15±0.70/ml in the medium-volume proteinuria group, and 3.48±1.27/ml in the large-volume proteinuria group. There was no significant difference between the small- and medium- volume proteinuria groups, and there were significant differences between other groups （P〈0.05）. The positive podocyte number tended to increase as proteinuria was increased. By Pearson analysis, the correlation between podocyte number and proteinuria was podocytes in urine from different groups of DN patients, CKD pc I sitive statistically. The difference of the number of positive -V group was significant statistically. The correlation between serum creatinine of CKD Ⅰ -Ⅲ group and positive podocytes in urine was positive statistically. The correlation between serumcreatinine of CKD Ⅳ- Ⅴ group and positive podocytes in urine was not significant statistically. The correlation between FBG and positive podocytes in urine was not significant either. Conclusion： The mechanism of the podocyte injury in DN patients is present. The podocyte injury in DN may positively correlate to proteinuria and serum creatinine of CKD Ⅰ -ⅢDN patients, but not to the FBG and serum creatinine of CKD Ⅳ-Ⅴ patients.
文摘The slit diaphragm bridging the neighboring foot pro-cesses functions as a fnal barrier of glomerular capil-lary wall for preventing the leak of plasma proteins into primary urine. It is now accepted that the dysfunction of the sit diaphragm contributes to the development of proteinuria in several glomerular diseases. Neph-rin, a gene product of NPHS1, a gene for a congenital nephrotic syndrome of Finnish type, constitutes an ex-tracellular domain of the slit diaphragm. Podocin was identified as a gene product of NPHS2 , a gene for a familial steroid-resistant nephrotic syndrome of French. Podocin binds the cytoplasmic domain of nephrin. After then, CD2 associated protein, NEPH1 and transient re-ceptor potential-6 were also found as crucial molecules of the slit diaphragm. In order to explore other novel molecules contributing to the development of protein-uria, we performed a subtraction hybridization assay with a normal rat glomerular RNA and a glomerular RNA of rats with a puromycin aminonucleoside ne-phropathy, a mimic of a human minimal change type nephrotic syndrome. Then we have found that synaptic vesicle protein 2B, ephrin-B1 and neurexin were already downregulated at the early stage of puromycin aminonucleoside nephropathy, and that these molecules were localized close to nephrin. It is conceivable that these molecules are the slit diaphragm associated molecules, which participate in the regulation of the barrier func-tion. These molecules could be targets to establish a novel therapy for nephrotic syndrome.
基金Supported by Protective Effect of Extract of Fructus Schisandrae Chinensis on Fibrosis of Diabetic Nephropathy among C57BL/6 Mice of National Natural Science Foundation of China(No.81150012)
文摘OBJECTIVE: To observe the effects and mechanisms of Bushenhuoxue on desmin and nephrin expression in mice podocytes, and to investigate its effects on wt1 expression in Wilms' tumor.METHODS: Adriamycin(ADR) was used to induce focal segmental glomerulous sclerosis(FSGS) in mice. Bushenhuoxue was used to treat FSGS for 6 weeks. We measured body mass and right renal mass, and determined serum albumin(ALB) levels,protein content in urine, and urinary protein and albumin creatinine ratio(UACR). Changes in renal tissue morphology were evaluated by microscopy.wt1 and nephrin expression in podocytes were detected using immunofluorescence. Expression levels of desmin, wt1 and nephrin m RNAs in renal tissue were determined using reverse transcription polymerase chain reaction assays.RESULTS: Protein levels in urine and UACR were significantly increased in FSGS model mice compared with Bushenhuoxue-treated and control mice.Body mass and ALB levels were decreased in FSGS mice compared with control and Bushenhuoxue-treated mice. Expression of the wt1 protein was observed in control mice. Compared with controls,wt1 expression levels were reduced in Bushenhuoxue-treated mice, and to a greater extent in FSGS mice. Nephrin protein expression was widespread in FSGS mice, and significantly reduced in control and Bushenhuoxue mice. Expression levels of wt1 and nephrin m RNAs in FSGS mice were lower compared with those in control and Bushenhuoxue-treated mice. Desmin m RNA levels in FSGS mice were reduced compared with those in control and Bushenhuoxue-treated mice.CONCLUSION: Bushenhuoxue ameliorated albuminuria in FSGS mice; this was possibly related to the up-regulation of wt1 and nephrin, and down-regulation of desmin.
基金supported by grants from the National Natu-ral Sciences Foundation of China (Nos. 30500245, 30871174, and 31050110433)a Medicine-technology Interdiscipline grant from Huazhong University of Science and Technology (No. 2010JC041)
文摘To investigate the protective effects of eplerenone on adriamycin-induced renal injury and the possible mechanisms involved,36 male Sprague-Dawley rats were randomly divided into control group,adriamycin nephropathy（AN） group and eplerenone-treated group（100 mg.kg-1.d-1 eplerenone）.Blood pressure,24-h urinary protein,serum potassium,sodium and creatinine were measured 28 days after adriamycin injection（a single tail intravenous injection of 6.5 mg/kg adriamycin）.The morphological changes of renal tissues were observed by light and electron microscopy.Immunohistochemistry and Western blotting were performed to examine the expression of TGF-β1 and desmin in renal cortex.The results showed that 28 days after adriamycin injection,there were no significant changes in the level of serum potassium,sodium,creatinine concentrations and blood pressure values in the rats of the three groups.Meanwhile,the 24-h proteinuria excretion in the AN group was significantly higher than that in the control group（P0.01）,but that in the eplerenone-treated group was substantially reduced when compared with that in the AN group（P0.05）.Mild mesangial cell proliferation and matrix expansion,diffuse deformation and confluence of foot processes in podocytes were found in the AN group.By contrast,rats in the eplerenone-treated group exhibited obvious attenuation of these morphological lesions.The protein expression of TGF-β1 and desmin in the AN group was markedly up-regulated in contrast to that in the control group（P0.01）,whereas that in the eplerenone-treated group was much lower than in the AN group（P0.05）.It was concluded that eplerenone may ameliorate the proteinuria and the development of pathological alteration in adriamycin-induced nephropathy presumably via the inhibition of cytokine release,and restore the morphology of podocytes independent of its blood pressure-lowing effects.
基金Supported by Shanghai Pudong New Area Leading Talents Training Program Project,No.PWR12020-02Shanghai Pudong New Area Excellent Young Medical Talents Training Program Project,No.PWRq2023-40Shanghai Pudong New Area Health and Family Planning Scientific Research Project,No.PW2022A-91.
文摘BACKGROUND Diabetic nephropathy(DN)is the most frequent chronic microvascular consequence of diabetes,and podocyte injury and malfunction are closely related to the development of DN.Studies have shown that corilagin(Cor)has hepatoprotective,anti-inflammatory,antibacterial,antioxidant,anti-hypertensive,antidiabetic,and anti-tumor activities.AIM To explore the protective effect of Cor against podocyte injury in DN mice and the underlying mechanisms.METHODS Streptozotocin and a high-fat diet were combined to generate DN mice models,which were then divided into either a Cor group or a DN group(n=8 in each group).Mice in the Cor group were intraperitoneally injected with Cor(30 mg/kg/d)for 12 wk,and mice in the DN group were treated with saline.Biochemical analysis was used to measure the blood lipid profiles.Hematoxylin and eosin staining was used to detect pathological changes in kidney tissue.Immunohistochemistry and Western blotting were used to assess the protein expression of nephrin and podocin.Mouse podocyte cells(MPC5)were cultured and treated with glucose(5 mmol/L),Cor(50μM),high glucose(HG)(30 mmol/L),and HG(30 mmol/L)plus Cor(50μM).Real-time quantitative PCR and Western blotting RESULTS Compared with the control group,the DN mice models had increased fasting blood glucose,glycosylated hemoglobin,triglycerides,and total cholesterol,decreased nephrin and podocin expression,increased apoptosis rate,elevated inflammatory cytokines,and enhanced oxidative stress.All of the conditions mentioned above were alleviated after intervention with Cor.In addition,Cor therapy improved SIRT1 and AMPK expression(P<0.001),inhibited reactive oxygen species and oxidative stress,and elevated autophagy in HG-induced podocytes(P<0.01).CONCLUSION Cor alleviates podocyte injury by regulating autophagy via the SIRT1-AMPK pathway,thereby exerting its protective impact on renal function in DN mice.
文摘BACKGROUND A number of recent studies indicate a transformation in the natural course of chronic kidney disease(CKD)in type 2 diabetes(T2D)patients:an increasing prevalence of declined renal function without proceeding to the accompanying elevation of albuminuria.It has been suggested that albuminuric and nonalbuminuric CKD patterns could be different in their phenotypes and pathogenic mechanisms.AIM To identify the risk factors and biomarkers of albuminuric and non-albuminuric patterns of CKD in patients with T2D.METHODS Three hundred sixty patients with T2D duration≥10 years were included in this observational cross-sectional study.The associations of a panel of demographic and clinical characteristics,complications,comorbidities,and metabolic and hematology parameters with albuminuric and non-albuminuric CKD patterns were analyzed.The urinary excretion of nephrin and podocin,two podocytespecific markers,and WAP-four-disulfide core domain protein 2(WFDC-2),a marker of tubulointerstitial fibrosis,was determined by ELISA in comparison with healthy controls.RESULTS Non-albuminuric CKD was associated with age≥65 years(P=0.0001),female sex(P=0.04),diabetes duration≥15 years(P=0.0009),and the use of diuretics(P=0.0005).Male sex(P=0.01),smoking(P=0.01),waist-to-hip ratio>1.0(P=0.01)and hemoglobin A1c(HbA1c)>8.0%(P=0.005)were risk factors for elevated albuminuria not accompanied by a decrease in estimated glomerular filtration rate(eGFR).Duration of diabetes≥15 years and the use of calcium channel blockers were risk factors for albuminuria with decreased eGFR(both P=0.01).In multivariate logistic regression analysis,age,HbA1c,female sex and diuretics were significant predictors for reduced eGFR,while waist-to-hip ratio,HbA1c and male sex were associated with elevated urinary albumin-to-creatinine ratio(UACR).Excretion of nephrin and podocin was increased in patients with albuminuria,regardless of decline in renal function(P<0.001),correlating positively with UACR.The urinary excretion of WFDC-2 was markedly higher in men than in women(P<0.000001).Men with T2D demonstrated increased WFDC-2 levels independently of the CKD pattern(all P<0.05).In T2D women,WFDC-2 excretion was increased in those with reduced renal function(P≤0.01),correlating negatively with eGFR.CONCLUSION The data provide further evidence that albuminuric and non-albuminuric CKD phenotypes correspond to different pathways of diabetic kidney disease progression.
