Mutations in the Rhodopsin(RHO)gene are the main cause of autosomal dominant retinitis pigmentosa(adRP),84%of which are pathogenic gain-of-function point mutations.Treatment strategies for adRP typically involve silen...Mutations in the Rhodopsin(RHO)gene are the main cause of autosomal dominant retinitis pigmentosa(adRP),84%of which are pathogenic gain-of-function point mutations.Treatment strategies for adRP typically involve silencing or ablating the pathogenic allele,while normal RHO protein replacement has no meaningful therapeutic benefit.Here,we present an adenine base editor(ABE)-mediated therapeutic approach for adRP caused by RHO point mutations in vivo.The correctable pathogenic mutations are screened and verified,including T17M,Q344ter,and P347L.Two adRP animal models are created carrying the class 1(Q344ter)and class 2(T17M)mutations,and dual AAV-delivered ABE can effectively repair both mutations in vivo.The early intervention of ABE8e efficiently corrects the Q344ter mutation that causes a severe form of adRP,delays photoreceptor death,and restores retinal function and visual behavior.These results suggest that ABE is a promising alternative to treat RHO mutation-associated adRP.Our work provides an effective spacer-mediated point mutation correction therapy for dominantly inherited ocular disorders.展开更多
BACKGROUND Sepsis is a severe illness characterized by systemic and multiorgan reactive responses and damage.However,the impact of sepsis on the bone marrow,particularly on bone marrow mesenchymal stem cells(BMSCs),is...BACKGROUND Sepsis is a severe illness characterized by systemic and multiorgan reactive responses and damage.However,the impact of sepsis on the bone marrow,particularly on bone marrow mesenchymal stem cells(BMSCs),is less reported.BMSCs are critical stromal cells in the bone marrow microenvironment that maintain bone stability and hematopoietic homeostasis;however,the impairment caused by sepsis remains unknown.AIM To investigate the effects of sepsis on BMSCs and the underlying mechanisms.METHODS BMSCs were obtained from healthy donors and patients with sepsis.We compared the self-renewal capacity,differentiation potential,and hematopoietic supportive ability in vitro.Senescence of septic BMSCs was assessed usingβ-galactosidase staining,senescence-associated secretory phenotype,intracellular reactive oxygen species levels,and the expression of P16 and P21.Finally,the changes in septic BMSCs after nicotinamide adenine dinucleotide(NAD)treatment were evaluated.RESULTS Septic BMSCs showed decreased proliferation and self-renewal,bias towards adipogenic differentiation,and weakened osteogenic differentiation.Additionally,hematopoietic supportive capacity declines in sepsis.The levels of aging markers were significantly higher in the septic BMSCs.After NAD treatment,the proliferation capacity of septic BMSCs showed a recovery trend,with increased osteogenic and hematopoietic supportive capacities.Sepsis resulted in decreased expression of sirtuin 3(SIRT3)in BMSCs,whereas NAD treatment restored SIRT3 expression,enhanced superoxide dismutase enzyme activity,reduced intracellular reactive oxygen species levels,maintained mitochondrial stability and function,and ultimately rejuvenated septic BMSCs.CONCLUSION Sepsis accelerates the aging of BMSCs,as evidenced by a decline in self-renewal and osteogenic capabilities,as well as weakened hematopoietic support functions.These deficiencies can be effectively reversed via the NAD/SIRT3/superoxide dismutase pathway.展开更多
Adenine phosphoribosyltransferase(APRT)deficiency is a rare autosomal recessive disease leading to generation of large amounts of 2,8-dihydroxyadenine(DHA).DHA is excreted in urine,where it precipitates into crystals ...Adenine phosphoribosyltransferase(APRT)deficiency is a rare autosomal recessive disease leading to generation of large amounts of 2,8-dihydroxyadenine(DHA).DHA is excreted in urine,where it precipitates into crystals due to its low solubility.DHA crystals can aggregate into stones or cause injury to the renal parenchyma(DHA nephropathy).Recurrent urolithiasis and DHA nephropathy are the two clinical manifestations of APRT deficiency.Diagnosis of APRT deficiency can be made during childhood as well as adulthood.Diagnosis mainly relies on the recognition of DHA in stones or urine crystals.Measurement of APRT activity and genetic testing are useful for confirmation of diagnosis,for family screening and should be considered in difficult cases of urolithiasis or crystalline nephropathy.Allopurinol therapy is the cornerstone of treatment and is highly effective in preventing recurrence of stones and kidney disease.High fluid intake and dietary modifications are also recommended.Early diagnosis and treatment are of paramount importance to prevent renal damage.Unfortunately,diagnosis of APRT deficiency is often overlooked and irreversible renal failure still occurs in a substantial proportion of patients.Clinicians must be alert to the possibility of APRT deficiency and consider the appropriate diagnostic tests in certain cases.This review discusses the genetic and biochemical mechanisms of APRT deficiency,and the issues of diagnosis and management.展开更多
Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups: normal c...Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups: normal control group (NCG) consisted of 8 rats, adenine treated group (ATG) 28 rats, and matrine treated group (MTG) 24 rats. Each rat in ATG and MTG was gavaged with adenine (250 mg·kg^-1·d^-1 ) for 21 d. After gavage with adenine for one week, each rat in MTG was administered intraperitoneally matrine(20 mg·kg^-1·d^-1 ) in vehicle ( 1 mL of 0.9% sodium chloride) daily. On days 14, 21, and 28, the serum levels of urea nitrogen, creatinine, and IL-6 were determined and the rat kidneys of ATG, MTG and NCGwere examined pathologically. Radioimmunoassay for serum IL- 6 immunohistochemical staining for TGF-β1 expression in the kidney and semiquantitative analysis were performed. HE staining for semiquantitative analysis of tubulointerstitial injury. Results The serum levels of urea nitrogen and creatinine in MTG were lower as compare to ATG ( P 〈 0.05 ) whereas serum IL- 6 and renal TGF-β1 expression levels were significantly lower than those in ATG (P 〈0.05 ), but all these indexes were higher than those in NCG (P 〈 0.01 ). In MTG, the index of tubulointerstitial lesion was lower than that in ATG (P 〈 0.05 ). Conclusion Matrine inhibits the renal tubulointerstial fibrosis in the adenine-induced rat model by suppressing serum level of IL-6 and expression of TGF-β1 in the tubulointerstitium.展开更多
Precise base editing is highly desired in plant functional genomic research and crop molecular breeding. In this study, we constructed a rice-codon optimized adenine base editor(ABE)-nC as9 tool that induced targeted ...Precise base editing is highly desired in plant functional genomic research and crop molecular breeding. In this study, we constructed a rice-codon optimized adenine base editor(ABE)-nC as9 tool that induced targeted A·T to G·C point mutation of a key single nucleotide polymorphism site in an important agricultural gene. Combined with the modified single-guide RNA variant, our plant ABE tool can efficiently achieve adenine base editing in the rice genome.展开更多
Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under...Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under normal circumstances, reactive oxygen species mediate a number of important cellular functions, including the facilitation of adaptive immunity. In pathogenic circumstances, however,excess reactive oxygen species generated by NOX promotes apoptotic cell death. In ischemic stroke, in particular, it has been shown that both NOX activation and derangements in glucose metabolism result in increased apoptosis. Moreover, recent studies have established that glucose, as a NOX substrate, plays a vital role in the pathogenesis of reperfusion injury. Thus, NOX inhibition has the potential to mitigate the deleterious impact of hyperglycemia on stroke. In this paper, we provide an overview of this research,coupled with a discussion of its implications for the development of NOX inhibition as a strategy for the treatment of ischemic stroke. Both inhibition using apocynin, as well as the prospect of developing more specific inhibitors based on what is now understood of the biology of NOX assembly and activation, will be highlighted in the course of our discussion.展开更多
Adenine is commonly used to establish the animal models for chronic kidney injury and its renal interstitial fibrosis. As an endogenous substance, adenine-induced kidney damage has not yet been fully studied and eluci...Adenine is commonly used to establish the animal models for chronic kidney injury and its renal interstitial fibrosis. As an endogenous substance, adenine-induced kidney damage has not yet been fully studied and elucidated, except for inflammatory reaction. Here we analyzed the proteomics of kidney of rats after adenine overloading using LS-MS/MS assay, and observed the role of anemoside B4(B4). The results showed that adenine could down-regulate 285 proteins and up-regulate 164 proteins in rat kidney tissue compared with the normal group. Down-regulated proteins mainly affected related pathways, such as energy metabolism, while up-regulated proteins affected inflammatory response pathways and metabolic pathways. B4 could significantly reverse the down-regulation of about 40 proteins, which were involved in mitochondria, redox processes, extracellular exosomes, acetylation and other signaling pathways. Simultaneously, B4 could inhibit the up-regulation of five proteins caused by adenine, which were involved in cell cycle, oocyte meiosis, PI3 K-Akt and other signaling pathways. Further experimental results of mRNA expression using real-time PCR assay supported the proteomic analysis. Therefore, we proposed that the damage of rat kidney caused by adenine was more complicated, not only with an inflammatory reaction, but also with extensive effects to various metabolic processes in the body. This work provided a valuable clue for comprehensive understanding of adenine-induced renal damage.展开更多
Oxaliplatin, an anticancer drug commonly used to treat colorectal cancer and other tumors, has a number of serious side effects, most notably neuropathy and ototoxicity. To gain insights into its ototoxic profile, oxa...Oxaliplatin, an anticancer drug commonly used to treat colorectal cancer and other tumors, has a number of serious side effects, most notably neuropathy and ototoxicity. To gain insights into its ototoxic profile, oxaliplatin was applied to rat cochlear organ cultures. Consistent with it neurotoxic propensity, oxaliplatin selectively damaged nerve fibers at a very low dose 1 μM. In contrast, the dose required to damage hair cells and spiral ganglion neurons was 50 fold higher (50 μM). Oxailiplatin-induced cochlear lesions initial-ly increased with dose, but unexpectedly decreased at very high doses. This non-linear dose response could be related to depressed oxaliplatin uptake via active transport mechanisms. Previous studies have demon-strated that axonal degeneration involves biologically active processes which can be greatly attenuated by nicotinamide adenine dinucleotide (NAD+). To determine if NAD+would protect spiral ganglion axons and the hair cells from oxaliplatin damage, cochlear cultures were treated with oxaliplatin alone at doses of 10 μM or 50 μM respectively as controls or combined with 20 mM NAD+. Treatment with 10 μM oxaliplatin for 48 hours resulted in minor damage to auditory nerve fibers, but spared cochlear hair cells. However, when cochlear cultures were treated with 10 μM oxaliplatin plus 20 mM NAD+, most auditory nerve fibers were intact. 50 μM oxaliplatin destroyed most of spiral ganglion neurons and cochlear hair cells with apop-totic characteristics of cell fragmentations. However, 50 μM oxaliplatin plus 20 mM NAD+treatment great-ly reduced neuronal degenerations and hair cell missing. The results suggested that NAD+provides signifi-cant protection against oxaliplatin-induced neurotoxicity and ototoxicity, which may be due to its actions of antioxidant, antiapoptosis, and energy supply.展开更多
Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5′-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP cou...Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5′-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP could distinctly increase the activities of purine nucleoside phosphorylase (PNPase), uridine phosphorylase (UPase) and thymidine phosphorylase (TPase) when they were added into medium from 0 to 8 h. In the process of enzymatic synthesis of adenine arabinoside from adenine and uracil arabinoside with wet cells of Enterobacter aerogenes DGO-04 induced by cytidine or CMP, the reaction time could be shortened from 36 to 6 h. After enzymatic reaction the activity of NPase in the cells induced remained higher than that in the cells uninduced.展开更多
AIM: To explore the effect of hypobaric hypoxia on mitochondrial energy metabolism in rat liver. METHODS: Adult male Wistar rats were exposed to a hypobadc chamber simulating 5000 m high altitude for 23 h every day ...AIM: To explore the effect of hypobaric hypoxia on mitochondrial energy metabolism in rat liver. METHODS: Adult male Wistar rats were exposed to a hypobadc chamber simulating 5000 m high altitude for 23 h every day for 0 (H0), 1 (H1), 5 (H5), 15 (H15) and 30 d (H30) respectively. Rats were sacrificed by decapitation and liver was removed. Liver mitochondria were isolated by differential centrifugation program. The size of adenine nucleotide pool (ATP ADP, and AMP) in tissue and mitochondria was separated and measured by high performance liquid chromatography (HPLC). The adenine nucleotide transporter (ANT) activity was determined by isotopic technique. The ANT total protein level was determined by Western blot. RESULTS: Compared with H0 group, intra-mitochondrial ATP content decreased in all hypoxia groups. However, the H5 group reached the lowest point (70.6%) (P〈 0.01) when compared to the control group. Intra-mitochondrial ADP and AMP level showed similar change in all hypoxia groups and were significantly lower than that in H0 group, In addition, extra-mitochondrial ATP and ADP content decreased significantly in all hypoxia groups. Furthermore, extra-mitochondrial AMP in groups H5, H15 and H30 was significantly lower than that in H0 group, whereas HI group had no marked change compared to the control situation. The activity of ANT in hypoxia groups decreased significantly, which was the lowest in H5 group (55.7%) (P〈0.01) when compared to H0 group. ANT activity in H30 group was higher than in H15 group, but still lower than that in H0 group. ANT protein level in H5, H15, H30 groups, compared with H0 group decreased significantly, which in H5 group was the lowest, being 27.1% of that in H0 group (P〈0.01). ANT protein level in H30 group was higher than in H15 group, but still lower than in H0 group. CONCLUSION: Hypobaric hypoxia decreases the mitochondrial ATP content in rat liver, while mitochondrial ATP level recovers during long-term hypoxia exposure. The lower level of extra-mitochondrial ATP may be related to the decrease of ANT activity during hypoxia exposure.展开更多
Among all the DNA components, extremely redox-active guanine (G) and adenine (A) bases are subject to facile loss of an electron and form cation radicals (G+" and A+') when exposed to irradiation or radical ...Among all the DNA components, extremely redox-active guanine (G) and adenine (A) bases are subject to facile loss of an electron and form cation radicals (G+" and A+') when exposed to irradiation or radical oxidants. The subsequent deprotonation of G+' and A+' can invoke DNA damage or interrupt hole transfer in DNA. However, compared with intensive reports for G+, studies on the deprotonation of A+ are still limited at present. Herein, we investigate the deprotonation behavior of A+. by time-resolved laser flash photolysis. The deprotonation product of A(N6-H)' is observed and the deprotonation rate constant, (2.0±0.1)×10 7 s-1, is obtained at room temperature. Further, the deprotonation rate con- stants of A+. are measured at temperatures varying from 280 K to 300 K, from which the activation energy for the N6-H deprotonation is determined to be (17.1±1.0) kJ/mol by Arrhenius equation. In addition, by incorporating the aqueous solvent effect, we perform density functional theory calculations for A+ deprotonation in free base and in duplex DNA. Together with experimental results, the deprotonation mechanisms of A+ in free base and in duplex DNA are revealed, which are of fundamental importance for understanding the oxidative DNA damage and designing DNA-based electrochemical devices.展开更多
Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic small vessel disease caused by mutations in the NOTCH3 gene. However, the pathogenesis of CADASIL rem...Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic small vessel disease caused by mutations in the NOTCH3 gene. However, the pathogenesis of CADASIL remains unclear, and patients have limited treatment options. Here, we use human induced pluripotent stem cells (hiPSCs) generated from the peripheral blood mononuclear cells of a patient with CADASIL carrying a heterozygous NOTCH3 mutation (c.1261C>T, p.R421C) to develop a disease model. The correction efficiency of different adenine base editors (ABEs) is tested using the HEK293T-NOTCH3 reporter cell line. ABEmax is selected based on its higher efficiency and minimization of predicted off-target effects. Vascular smooth muscle cells (VSMCs) differentiated from CADASIL hiPSCs show NOTCH3 deposition and abnormal actin cytoskeleton structure, and the abnormalities are recovered in corrected hiPSC-derived VSMCs. Furthermore, CADASIL blood vessel organoids generated for in vivo modeling show altered expression of genes related to disease phenotypes, including the downregulation of cell adhesion, extracellular matrix organization, and vessel development. The dual adeno-associated virus (AAV) split-ABEmax system is applied to the genome editing of vascular organoids with an average editing efficiency of 8.82%. Collectively, we present potential genetic therapeutic strategies for patients with CADASIL using blood vessel organoids and the dual AAV split-ABEmax system.展开更多
Two new CdⅡ-based coordination polymers(CPs) with mixed adenine(Hade) nucleobase and 5-nitroisophathalate(nip) ligands, {[Cd(Hade)_(0.5)(H_2O)_2(nip)]·H_2O}n 1 and {[Cd(Hade)(H_2O)_(1.25)(CH_3OH)0.75(nip)]·...Two new CdⅡ-based coordination polymers(CPs) with mixed adenine(Hade) nucleobase and 5-nitroisophathalate(nip) ligands, {[Cd(Hade)_(0.5)(H_2O)_2(nip)]·H_2O}n 1 and {[Cd(Hade)(H_2O)_(1.25)(CH_3OH)0.75(nip)]·0.75 CH_3OH·0.5H_2 O}_n 2, were successfully obtained by varying the preparation methods and structurally characterized. Crystal data for 1: monoclinic, C2/c space group with a = 10.5546(6), b = 17.3496(6), c = 16.1198(9) ?, β = 104.2800(10)o, V = 2860.6(2) ?3, Dc = 2.058 g/cm^3, Mr = 443.13, Z = 8, F(000) = 1752, μ = 1.585 mm^(–1), the final R = 0.0394 and wR = 0.1109 for 2285 observed reflections with I > 2σ(I). For 2: triclinic, P1 space group with a = 10.2032(7), b = 10.5098(8), c = 11.0223(8) ?, a = 65.7050(10)o, β = 74.5750(10)o, g = 61.5280(10)o, V = 943.38(12) ?~3, Dc = 1.888 g/cm3, Mr = 536.24, Z = 2, F(000) = 537, μ = 1.225 mm^(–1), the final R = 0.0225 and wR = 0.0702 for 3143 observed reflections with I > 2σ(I). 1 presents a crisscrossed layer with mutually orthogonal {Cd(nip)} chains aggregated by neutral m-N(7),N(9)-Hade connector. By contrast, 2 displays a linear chain with CdⅡ ions extended by bis-bidentate chelating-nip2–connectors, which are further assembled into a broad ribbon by N-H···N hydrogen-bonding interactions. Additionally, the two solid-state samples with comparable thermal stability exhibit favorable luminescent emissions at room temperature, suggesting their potential applications as fluorescence materials.展开更多
Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral palsy.Currently,there are few effective clinical treatments for neonatal hypoxic-ischemic brain injury.Here,we i...Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral palsy.Currently,there are few effective clinical treatments for neonatal hypoxic-ischemic brain injury.Here,we investigated the neuroprotective and molecular mechanisms of exogenous nicotinamide adenine dinucleotide,which can protect against hypoxic injury in adulthood,in a mouse model of neonatal hypoxic-ischemic brain injury.In this study,nicotinamide adenine dinucleotide(5 mg/kg)was intraperitoneally administered 30 minutes befo re surgery and every 24 hours thereafter.The results showed that nicotinamide adenine dinucleotide treatment improved body weight,brain structure,adenosine triphosphate levels,oxidative damage,neurobehavioral test outcomes,and seizure threshold in experimental mice.Tandem mass tag proteomics revealed that numerous proteins were altered after nicotinamide adenine dinucleotide treatment in hypoxic-ischemic brain injury mice.Parallel reaction monitoring and western blotting confirmed changes in the expression levels of proteins including serine(or cysteine)peptidase inhibitor,clade A,member 3N,fibronectin 1,5'-nucleotidase,cytosolic IA,microtubule associated protein 2,and complexin 2.Proteomics analyses showed that nicotinamide adenine dinucleotide ameliorated hypoxic-ischemic injury through inflammation-related signaling pathways(e.g.,nuclear factor-kappa B,mitogen-activated protein kinase,and phosphatidylinositol 3 kinase/protein kinase B).These findings suggest that nicotinamide adenine dinucleotide treatment can improve neurobehavioral phenotypes in hypoxic-ischemic brain injury mice through inflammation-related pathways.展开更多
The fabrication of poly(2,6-pyridinedicarboxylic acid)/MWNTs modified glass electrode(PPDA/MWNTs/GCE) was proposed and used for individual or simultaneous determination of guanine and adenine.The performances of t...The fabrication of poly(2,6-pyridinedicarboxylic acid)/MWNTs modified glass electrode(PPDA/MWNTs/GCE) was proposed and used for individual or simultaneous determination of guanine and adenine.The performances of the PPDA/MWNTs/GCE were characterized with cyclic voltammetry(CV).The modified electrode exhibited enhanced electrocatalytic behavior and good stability for the detection of guanine and adenine.Differential pulse voltammetry(DPV) was used to determine the concentration of guanine,adenine.The detection limit(S/N = 3) for guanine and adenine was 0.045μmol/L and 0.05μmol/L,respectively.The electrochemical method for the measurement of guanine and adenine in calf thymus DNA was also developed with this modified electrode and the result was satisfactory.展开更多
The effects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigated in vivo and in vitro. Chitosan were hydrolyzed using chitosanase at pH 6-7 and 37℃ for ...The effects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigated in vivo and in vitro. Chitosan were hydrolyzed using chitosanase at pH 6-7 and 37℃ for 24h to obtain LMWC. In vitro, the effect of LMWC on the proliferation of renal tubular epithelial cells (RTEC) showed that it had no cytotoxic effect and could promote cell growtfi. For the in vivo experiment, chronic renal failure rats induced by adenine were randomly divided into control group, Niaoduqing group, and high-, medium- and low-dose LMWC groups. For each group, we detected serum creatinine (SCR), blood urea nitrogen (BUN), and total superoxide dismutase (T-SOD), glutathione oxidase (GSH-Px) activities of renal tissue, and obtained the ratio of kidney weight/body weight, pathological changes of kidney. The levels of serum SCR, BUN were higher in the adenine-induced rats than those in the control group, indicating that the rat chronic renal failure model worked successfully. The re- suits after treatment showed that LMWC could reduce the SCR and BUN levels and enhance the activities/levels of T-SOD and GSH-PX in kidney compared to control group. Histopathological examination revealed that adenine-induced renal alterations were restored by LMWC at three tested dosages, especially at the low dosage of 100mgkg-1 d-1.展开更多
Dear Editor,DNA methylation is a key epigenetic regulatory approach for many biological processes,such as genomic imprinting,epigenetic memory maintenance,aging,and neural development.In addition to 5-methylcytosine,D...Dear Editor,DNA methylation is a key epigenetic regulatory approach for many biological processes,such as genomic imprinting,epigenetic memory maintenance,aging,and neural development.In addition to 5-methylcytosine,DNA methylation at N6-deoxyadenosine(N6-mA)is the most prevalent DNA modification in prokaryotes[1].展开更多
Eukaryotic DNA methylation has been receiving increasing attention for its crucial epigenetic regulatory function.The recently developed single-molecule real-time(SMRT)sequencing technology provides an efficient way t...Eukaryotic DNA methylation has been receiving increasing attention for its crucial epigenetic regulatory function.The recently developed single-molecule real-time(SMRT)sequencing technology provides an efficient way to detect DNA N6-methyladenine(6mA)and N4-methylcytosine(4mC)modifications at a single-nucleotide resolution.The family Rosaceae contains horticultural plants with a wide range of economic importance.However,little is currently known regarding the genome-wide distribution patterns and functions of 6mA and 4mC modifications in the Rosaceae.In this study,we present an integrated DNA 6mA and 4mC modification database for the Rosaceae(MDR,http://mdr.xieslab.org).MDR,the first repository for displaying and storing DNA 6mA and 4mC methylomes from SMRT sequencing data sets for Rosaceae,includes meta and statistical information,methylation densities,Gene Ontology enrichment analyses,and genome search and browse for methylated sites in NCBI.MDR provides important information regarding DNA 6mA and 4mC methylation and may help users better understand epigenetic modifications in the family Rosaceae.展开更多
BACKGROUND There is no established treatment to impede the progression or restore kidney function in human chronic kidney disease(CKD).AIM To examine the efficacy of cultured human CD34+cells with enhanced proliferati...BACKGROUND There is no established treatment to impede the progression or restore kidney function in human chronic kidney disease(CKD).AIM To examine the efficacy of cultured human CD34+cells with enhanced proliferating potential in kidney injury in mice.METHODS Human umbilical cord blood(UCB)-derived CD34+cells were incubated for one week in vasculogenic conditioning medium.Vasculogenic culture significantly increased the number of CD34+cells and their ability to form endothelial progenitor cell colony-forming units.Adenineinduced tubulointerstitial injury of the kidney was induced in immunodeficient non-obese diabetic/severe combined immunodeficiency mice,and cultured human UCB-CD34+cells were administered at a dose of 1×106/mouse on days 7,14,and 21 after the start of adenine diet.RESULTS Repetitive administration of cultured UCB-CD34+cells significantly improved the time-course of kidney dysfunction in the cell therapy group compared with that in the control group.Both interstitial fibrosis and tubular damage were significantly reduced in the cell therapy group compared with those in the control group(P<0.01).Microvasculature integrity was significantly preserved(P<0.01)and macrophage infiltration into kidney tissue was dramatically decreased in the cell therapy group compared with those in the control group(P<0.001).CONCLUSION Early intervention using human cultured CD34+cells significantly improved the progression of tubulointerstitial kidney injury.Repetitive administration of cultured human UCB-CD34+cells significantly improved tubulointerstitial damage in adenine-induced kidney injury in mice via vasculoprotective and anti-inflammatory effects.展开更多
基金funded by the National Key Research and Development Program of China(2023YFC2506100)the National Natural Science Foundation of China(31971365,32371509,32001063,and 82271688)+3 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2019BT02Y276)the Guangdong Basic and Applied Basic Research Foundation(2023A1515010176)the grant from MOE Key Laboratory of Gene Function and Regulation,the Guangzhou Science and Technology Planning Project(2023A04J1952)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(23ptpy59).
文摘Mutations in the Rhodopsin(RHO)gene are the main cause of autosomal dominant retinitis pigmentosa(adRP),84%of which are pathogenic gain-of-function point mutations.Treatment strategies for adRP typically involve silencing or ablating the pathogenic allele,while normal RHO protein replacement has no meaningful therapeutic benefit.Here,we present an adenine base editor(ABE)-mediated therapeutic approach for adRP caused by RHO point mutations in vivo.The correctable pathogenic mutations are screened and verified,including T17M,Q344ter,and P347L.Two adRP animal models are created carrying the class 1(Q344ter)and class 2(T17M)mutations,and dual AAV-delivered ABE can effectively repair both mutations in vivo.The early intervention of ABE8e efficiently corrects the Q344ter mutation that causes a severe form of adRP,delays photoreceptor death,and restores retinal function and visual behavior.These results suggest that ABE is a promising alternative to treat RHO mutation-associated adRP.Our work provides an effective spacer-mediated point mutation correction therapy for dominantly inherited ocular disorders.
基金Shanghai Natural Science Foundation,No.21ZR1452300the Clinical Research Innovation Plan of Shanghai General Hospital,No.CCTR-2022B04.
文摘BACKGROUND Sepsis is a severe illness characterized by systemic and multiorgan reactive responses and damage.However,the impact of sepsis on the bone marrow,particularly on bone marrow mesenchymal stem cells(BMSCs),is less reported.BMSCs are critical stromal cells in the bone marrow microenvironment that maintain bone stability and hematopoietic homeostasis;however,the impairment caused by sepsis remains unknown.AIM To investigate the effects of sepsis on BMSCs and the underlying mechanisms.METHODS BMSCs were obtained from healthy donors and patients with sepsis.We compared the self-renewal capacity,differentiation potential,and hematopoietic supportive ability in vitro.Senescence of septic BMSCs was assessed usingβ-galactosidase staining,senescence-associated secretory phenotype,intracellular reactive oxygen species levels,and the expression of P16 and P21.Finally,the changes in septic BMSCs after nicotinamide adenine dinucleotide(NAD)treatment were evaluated.RESULTS Septic BMSCs showed decreased proliferation and self-renewal,bias towards adipogenic differentiation,and weakened osteogenic differentiation.Additionally,hematopoietic supportive capacity declines in sepsis.The levels of aging markers were significantly higher in the septic BMSCs.After NAD treatment,the proliferation capacity of septic BMSCs showed a recovery trend,with increased osteogenic and hematopoietic supportive capacities.Sepsis resulted in decreased expression of sirtuin 3(SIRT3)in BMSCs,whereas NAD treatment restored SIRT3 expression,enhanced superoxide dismutase enzyme activity,reduced intracellular reactive oxygen species levels,maintained mitochondrial stability and function,and ultimately rejuvenated septic BMSCs.CONCLUSION Sepsis accelerates the aging of BMSCs,as evidenced by a decline in self-renewal and osteogenic capabilities,as well as weakened hematopoietic support functions.These deficiencies can be effectively reversed via the NAD/SIRT3/superoxide dismutase pathway.
文摘Adenine phosphoribosyltransferase(APRT)deficiency is a rare autosomal recessive disease leading to generation of large amounts of 2,8-dihydroxyadenine(DHA).DHA is excreted in urine,where it precipitates into crystals due to its low solubility.DHA crystals can aggregate into stones or cause injury to the renal parenchyma(DHA nephropathy).Recurrent urolithiasis and DHA nephropathy are the two clinical manifestations of APRT deficiency.Diagnosis of APRT deficiency can be made during childhood as well as adulthood.Diagnosis mainly relies on the recognition of DHA in stones or urine crystals.Measurement of APRT activity and genetic testing are useful for confirmation of diagnosis,for family screening and should be considered in difficult cases of urolithiasis or crystalline nephropathy.Allopurinol therapy is the cornerstone of treatment and is highly effective in preventing recurrence of stones and kidney disease.High fluid intake and dietary modifications are also recommended.Early diagnosis and treatment are of paramount importance to prevent renal damage.Unfortunately,diagnosis of APRT deficiency is often overlooked and irreversible renal failure still occurs in a substantial proportion of patients.Clinicians must be alert to the possibility of APRT deficiency and consider the appropriate diagnostic tests in certain cases.This review discusses the genetic and biochemical mechanisms of APRT deficiency,and the issues of diagnosis and management.
文摘Aim ,To study the mechanism relative to therapeutic effects of matrine on adenine-induced renal interstitial fibrosis in rats. Methods Sixty male Wistar rats were selected and randomly divided into 3 groups: normal control group (NCG) consisted of 8 rats, adenine treated group (ATG) 28 rats, and matrine treated group (MTG) 24 rats. Each rat in ATG and MTG was gavaged with adenine (250 mg·kg^-1·d^-1 ) for 21 d. After gavage with adenine for one week, each rat in MTG was administered intraperitoneally matrine(20 mg·kg^-1·d^-1 ) in vehicle ( 1 mL of 0.9% sodium chloride) daily. On days 14, 21, and 28, the serum levels of urea nitrogen, creatinine, and IL-6 were determined and the rat kidneys of ATG, MTG and NCGwere examined pathologically. Radioimmunoassay for serum IL- 6 immunohistochemical staining for TGF-β1 expression in the kidney and semiquantitative analysis were performed. HE staining for semiquantitative analysis of tubulointerstitial injury. Results The serum levels of urea nitrogen and creatinine in MTG were lower as compare to ATG ( P 〈 0.05 ) whereas serum IL- 6 and renal TGF-β1 expression levels were significantly lower than those in ATG (P 〈0.05 ), but all these indexes were higher than those in NCG (P 〈 0.01 ). In MTG, the index of tubulointerstitial lesion was lower than that in ATG (P 〈 0.05 ). Conclusion Matrine inhibits the renal tubulointerstial fibrosis in the adenine-induced rat model by suppressing serum level of IL-6 and expression of TGF-β1 in the tubulointerstitium.
基金supported by the National Natural Science Foundation of China (Grant No. 31501239)the Genetically Modified Breeding Major Projects (Grant No. 2016ZX08010-002-008)
文摘Precise base editing is highly desired in plant functional genomic research and crop molecular breeding. In this study, we constructed a rice-codon optimized adenine base editor(ABE)-nC as9 tool that induced targeted A·T to G·C point mutation of a key single nucleotide polymorphism site in an important agricultural gene. Combined with the modified single-guide RNA variant, our plant ABE tool can efficiently achieve adenine base editing in the rice genome.
基金partially supported by Merit Review Award(I01RX-001964-01)from the US Department of Veterans Affairs Rehabilitation Research and Development Service(to YD)the National Natural Science Foundation of China(81501141)+1 种基金Beijing New Star of Science and Technology Program of China(xx2016061)Beijing Tongzhou District Financial Fund,and Scientific Research Common Program of Beijing Municipal Commission of Education,China(KM201610025028)(to XG)
文摘Nicotinamide adenine dinucleotide phosphate oxidase(NOX) is a multisubunit enzyme complex that utilizes nicotinamide adenine dinucleotide phosphate to produce superoxide anions and other reactive oxygen species. Under normal circumstances, reactive oxygen species mediate a number of important cellular functions, including the facilitation of adaptive immunity. In pathogenic circumstances, however,excess reactive oxygen species generated by NOX promotes apoptotic cell death. In ischemic stroke, in particular, it has been shown that both NOX activation and derangements in glucose metabolism result in increased apoptosis. Moreover, recent studies have established that glucose, as a NOX substrate, plays a vital role in the pathogenesis of reperfusion injury. Thus, NOX inhibition has the potential to mitigate the deleterious impact of hyperglycemia on stroke. In this paper, we provide an overview of this research,coupled with a discussion of its implications for the development of NOX inhibition as a strategy for the treatment of ischemic stroke. Both inhibition using apocynin, as well as the prospect of developing more specific inhibitors based on what is now understood of the biology of NOX assembly and activation, will be highlighted in the course of our discussion.
基金National Innovative Drugs 13th Five-Year Major Special Project of China(Grant No.2018ZX09301030-002)
文摘Adenine is commonly used to establish the animal models for chronic kidney injury and its renal interstitial fibrosis. As an endogenous substance, adenine-induced kidney damage has not yet been fully studied and elucidated, except for inflammatory reaction. Here we analyzed the proteomics of kidney of rats after adenine overloading using LS-MS/MS assay, and observed the role of anemoside B4(B4). The results showed that adenine could down-regulate 285 proteins and up-regulate 164 proteins in rat kidney tissue compared with the normal group. Down-regulated proteins mainly affected related pathways, such as energy metabolism, while up-regulated proteins affected inflammatory response pathways and metabolic pathways. B4 could significantly reverse the down-regulation of about 40 proteins, which were involved in mitochondria, redox processes, extracellular exosomes, acetylation and other signaling pathways. Simultaneously, B4 could inhibit the up-regulation of five proteins caused by adenine, which were involved in cell cycle, oocyte meiosis, PI3 K-Akt and other signaling pathways. Further experimental results of mRNA expression using real-time PCR assay supported the proteomic analysis. Therefore, we proposed that the damage of rat kidney caused by adenine was more complicated, not only with an inflammatory reaction, but also with extensive effects to various metabolic processes in the body. This work provided a valuable clue for comprehensive understanding of adenine-induced renal damage.
文摘Oxaliplatin, an anticancer drug commonly used to treat colorectal cancer and other tumors, has a number of serious side effects, most notably neuropathy and ototoxicity. To gain insights into its ototoxic profile, oxaliplatin was applied to rat cochlear organ cultures. Consistent with it neurotoxic propensity, oxaliplatin selectively damaged nerve fibers at a very low dose 1 μM. In contrast, the dose required to damage hair cells and spiral ganglion neurons was 50 fold higher (50 μM). Oxailiplatin-induced cochlear lesions initial-ly increased with dose, but unexpectedly decreased at very high doses. This non-linear dose response could be related to depressed oxaliplatin uptake via active transport mechanisms. Previous studies have demon-strated that axonal degeneration involves biologically active processes which can be greatly attenuated by nicotinamide adenine dinucleotide (NAD+). To determine if NAD+would protect spiral ganglion axons and the hair cells from oxaliplatin damage, cochlear cultures were treated with oxaliplatin alone at doses of 10 μM or 50 μM respectively as controls or combined with 20 mM NAD+. Treatment with 10 μM oxaliplatin for 48 hours resulted in minor damage to auditory nerve fibers, but spared cochlear hair cells. However, when cochlear cultures were treated with 10 μM oxaliplatin plus 20 mM NAD+, most auditory nerve fibers were intact. 50 μM oxaliplatin destroyed most of spiral ganglion neurons and cochlear hair cells with apop-totic characteristics of cell fragmentations. However, 50 μM oxaliplatin plus 20 mM NAD+treatment great-ly reduced neuronal degenerations and hair cell missing. The results suggested that NAD+provides signifi-cant protection against oxaliplatin-induced neurotoxicity and ototoxicity, which may be due to its actions of antioxidant, antiapoptosis, and energy supply.
基金Project (No. 07C26213101283) supported by the Innovation Fundfor Technology Based Firms from the Ministry of Science andTechnology of China
文摘Nucleoside phosphorylases (NPases) were found to be induced in Enterobacter aerogenes DGO-04, and cytidine and cytidine 5′-monophosphate (CMP) were the best inducers. Five mmol/L to fifteen mmol/L cytidine or CMP could distinctly increase the activities of purine nucleoside phosphorylase (PNPase), uridine phosphorylase (UPase) and thymidine phosphorylase (TPase) when they were added into medium from 0 to 8 h. In the process of enzymatic synthesis of adenine arabinoside from adenine and uracil arabinoside with wet cells of Enterobacter aerogenes DGO-04 induced by cytidine or CMP, the reaction time could be shortened from 36 to 6 h. After enzymatic reaction the activity of NPase in the cells induced remained higher than that in the cells uninduced.
基金Supported by the Natural Science Foundation of China, No.30270509
文摘AIM: To explore the effect of hypobaric hypoxia on mitochondrial energy metabolism in rat liver. METHODS: Adult male Wistar rats were exposed to a hypobadc chamber simulating 5000 m high altitude for 23 h every day for 0 (H0), 1 (H1), 5 (H5), 15 (H15) and 30 d (H30) respectively. Rats were sacrificed by decapitation and liver was removed. Liver mitochondria were isolated by differential centrifugation program. The size of adenine nucleotide pool (ATP ADP, and AMP) in tissue and mitochondria was separated and measured by high performance liquid chromatography (HPLC). The adenine nucleotide transporter (ANT) activity was determined by isotopic technique. The ANT total protein level was determined by Western blot. RESULTS: Compared with H0 group, intra-mitochondrial ATP content decreased in all hypoxia groups. However, the H5 group reached the lowest point (70.6%) (P〈 0.01) when compared to the control group. Intra-mitochondrial ADP and AMP level showed similar change in all hypoxia groups and were significantly lower than that in H0 group, In addition, extra-mitochondrial ATP and ADP content decreased significantly in all hypoxia groups. Furthermore, extra-mitochondrial AMP in groups H5, H15 and H30 was significantly lower than that in H0 group, whereas HI group had no marked change compared to the control situation. The activity of ANT in hypoxia groups decreased significantly, which was the lowest in H5 group (55.7%) (P〈0.01) when compared to H0 group. ANT activity in H30 group was higher than in H15 group, but still lower than that in H0 group. ANT protein level in H5, H15, H30 groups, compared with H0 group decreased significantly, which in H5 group was the lowest, being 27.1% of that in H0 group (P〈0.01). ANT protein level in H30 group was higher than in H15 group, but still lower than in H0 group. CONCLUSION: Hypobaric hypoxia decreases the mitochondrial ATP content in rat liver, while mitochondrial ATP level recovers during long-term hypoxia exposure. The lower level of extra-mitochondrial ATP may be related to the decrease of ANT activity during hypoxia exposure.
文摘Among all the DNA components, extremely redox-active guanine (G) and adenine (A) bases are subject to facile loss of an electron and form cation radicals (G+" and A+') when exposed to irradiation or radical oxidants. The subsequent deprotonation of G+' and A+' can invoke DNA damage or interrupt hole transfer in DNA. However, compared with intensive reports for G+, studies on the deprotonation of A+ are still limited at present. Herein, we investigate the deprotonation behavior of A+. by time-resolved laser flash photolysis. The deprotonation product of A(N6-H)' is observed and the deprotonation rate constant, (2.0±0.1)×10 7 s-1, is obtained at room temperature. Further, the deprotonation rate con- stants of A+. are measured at temperatures varying from 280 K to 300 K, from which the activation energy for the N6-H deprotonation is determined to be (17.1±1.0) kJ/mol by Arrhenius equation. In addition, by incorporating the aqueous solvent effect, we perform density functional theory calculations for A+ deprotonation in free base and in duplex DNA. Together with experimental results, the deprotonation mechanisms of A+ in free base and in duplex DNA are revealed, which are of fundamental importance for understanding the oxidative DNA damage and designing DNA-based electrochemical devices.
基金funded by the National Natural Science Foundation of China(31971365)the Guangdong Basic and Applied Basic Research Foundation(2020B1515120090)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2019BT02Y276).
文摘Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a monogenic small vessel disease caused by mutations in the NOTCH3 gene. However, the pathogenesis of CADASIL remains unclear, and patients have limited treatment options. Here, we use human induced pluripotent stem cells (hiPSCs) generated from the peripheral blood mononuclear cells of a patient with CADASIL carrying a heterozygous NOTCH3 mutation (c.1261C>T, p.R421C) to develop a disease model. The correction efficiency of different adenine base editors (ABEs) is tested using the HEK293T-NOTCH3 reporter cell line. ABEmax is selected based on its higher efficiency and minimization of predicted off-target effects. Vascular smooth muscle cells (VSMCs) differentiated from CADASIL hiPSCs show NOTCH3 deposition and abnormal actin cytoskeleton structure, and the abnormalities are recovered in corrected hiPSC-derived VSMCs. Furthermore, CADASIL blood vessel organoids generated for in vivo modeling show altered expression of genes related to disease phenotypes, including the downregulation of cell adhesion, extracellular matrix organization, and vessel development. The dual adeno-associated virus (AAV) split-ABEmax system is applied to the genome editing of vascular organoids with an average editing efficiency of 8.82%. Collectively, we present potential genetic therapeutic strategies for patients with CADASIL using blood vessel organoids and the dual AAV split-ABEmax system.
基金supported by the National Natural Science Foundation of China(Nos.21571140 and 21671149)the Program for Innovative Research Team in University of Tianjin(TD13-5074)
文摘Two new CdⅡ-based coordination polymers(CPs) with mixed adenine(Hade) nucleobase and 5-nitroisophathalate(nip) ligands, {[Cd(Hade)_(0.5)(H_2O)_2(nip)]·H_2O}n 1 and {[Cd(Hade)(H_2O)_(1.25)(CH_3OH)0.75(nip)]·0.75 CH_3OH·0.5H_2 O}_n 2, were successfully obtained by varying the preparation methods and structurally characterized. Crystal data for 1: monoclinic, C2/c space group with a = 10.5546(6), b = 17.3496(6), c = 16.1198(9) ?, β = 104.2800(10)o, V = 2860.6(2) ?3, Dc = 2.058 g/cm^3, Mr = 443.13, Z = 8, F(000) = 1752, μ = 1.585 mm^(–1), the final R = 0.0394 and wR = 0.1109 for 2285 observed reflections with I > 2σ(I). For 2: triclinic, P1 space group with a = 10.2032(7), b = 10.5098(8), c = 11.0223(8) ?, a = 65.7050(10)o, β = 74.5750(10)o, g = 61.5280(10)o, V = 943.38(12) ?~3, Dc = 1.888 g/cm3, Mr = 536.24, Z = 2, F(000) = 537, μ = 1.225 mm^(–1), the final R = 0.0225 and wR = 0.0702 for 3143 observed reflections with I > 2σ(I). 1 presents a crisscrossed layer with mutually orthogonal {Cd(nip)} chains aggregated by neutral m-N(7),N(9)-Hade connector. By contrast, 2 displays a linear chain with CdⅡ ions extended by bis-bidentate chelating-nip2–connectors, which are further assembled into a broad ribbon by N-H···N hydrogen-bonding interactions. Additionally, the two solid-state samples with comparable thermal stability exhibit favorable luminescent emissions at room temperature, suggesting their potential applications as fluorescence materials.
基金supported by the National Natural Science Foundation of China,Nos.81871024 (to HN),82301957 (to XW),82001382 (to LL),62127810 (to HN)the Natural Science Foundation of Jiangsu Province of China,No.SBK2020040785 (to LL)。
文摘Neonatal hypoxic-ischemic brain injury is the main cause of hypoxic-ischemic encephalopathy and cerebral palsy.Currently,there are few effective clinical treatments for neonatal hypoxic-ischemic brain injury.Here,we investigated the neuroprotective and molecular mechanisms of exogenous nicotinamide adenine dinucleotide,which can protect against hypoxic injury in adulthood,in a mouse model of neonatal hypoxic-ischemic brain injury.In this study,nicotinamide adenine dinucleotide(5 mg/kg)was intraperitoneally administered 30 minutes befo re surgery and every 24 hours thereafter.The results showed that nicotinamide adenine dinucleotide treatment improved body weight,brain structure,adenosine triphosphate levels,oxidative damage,neurobehavioral test outcomes,and seizure threshold in experimental mice.Tandem mass tag proteomics revealed that numerous proteins were altered after nicotinamide adenine dinucleotide treatment in hypoxic-ischemic brain injury mice.Parallel reaction monitoring and western blotting confirmed changes in the expression levels of proteins including serine(or cysteine)peptidase inhibitor,clade A,member 3N,fibronectin 1,5'-nucleotidase,cytosolic IA,microtubule associated protein 2,and complexin 2.Proteomics analyses showed that nicotinamide adenine dinucleotide ameliorated hypoxic-ischemic injury through inflammation-related signaling pathways(e.g.,nuclear factor-kappa B,mitogen-activated protein kinase,and phosphatidylinositol 3 kinase/protein kinase B).These findings suggest that nicotinamide adenine dinucleotide treatment can improve neurobehavioral phenotypes in hypoxic-ischemic brain injury mice through inflammation-related pathways.
基金supported by National Natural Science Foundation of China(No.2097 104)the Key Project of Chinese Ministry of Education(No.210146)the Foundation of Hunan Provincial Department of Education(No. 08c341)
文摘The fabrication of poly(2,6-pyridinedicarboxylic acid)/MWNTs modified glass electrode(PPDA/MWNTs/GCE) was proposed and used for individual or simultaneous determination of guanine and adenine.The performances of the PPDA/MWNTs/GCE were characterized with cyclic voltammetry(CV).The modified electrode exhibited enhanced electrocatalytic behavior and good stability for the detection of guanine and adenine.Differential pulse voltammetry(DPV) was used to determine the concentration of guanine,adenine.The detection limit(S/N = 3) for guanine and adenine was 0.045μmol/L and 0.05μmol/L,respectively.The electrochemical method for the measurement of guanine and adenine in calf thymus DNA was also developed with this modified electrode and the result was satisfactory.
文摘The effects of low-molecular-weight-chitosan (LMWC) on chronic renal failure (CRF) rats induced by adenine were investigated in vivo and in vitro. Chitosan were hydrolyzed using chitosanase at pH 6-7 and 37℃ for 24h to obtain LMWC. In vitro, the effect of LMWC on the proliferation of renal tubular epithelial cells (RTEC) showed that it had no cytotoxic effect and could promote cell growtfi. For the in vivo experiment, chronic renal failure rats induced by adenine were randomly divided into control group, Niaoduqing group, and high-, medium- and low-dose LMWC groups. For each group, we detected serum creatinine (SCR), blood urea nitrogen (BUN), and total superoxide dismutase (T-SOD), glutathione oxidase (GSH-Px) activities of renal tissue, and obtained the ratio of kidney weight/body weight, pathological changes of kidney. The levels of serum SCR, BUN were higher in the adenine-induced rats than those in the control group, indicating that the rat chronic renal failure model worked successfully. The re- suits after treatment showed that LMWC could reduce the SCR and BUN levels and enhance the activities/levels of T-SOD and GSH-PX in kidney compared to control group. Histopathological examination revealed that adenine-induced renal alterations were restored by LMWC at three tested dosages, especially at the low dosage of 100mgkg-1 d-1.
基金The work was supported by grants from the National Institutes of Health(R01NS085176,R01GM111514,R01EY027347,R01EY030883,and R01EY031779)the Craig H.Neilsen Foundation(259450)the BrightFocus Foundation(G2017037).
文摘Dear Editor,DNA methylation is a key epigenetic regulatory approach for many biological processes,such as genomic imprinting,epigenetic memory maintenance,aging,and neural development.In addition to 5-methylcytosine,DNA methylation at N6-deoxyadenosine(N6-mA)is the most prevalent DNA modification in prokaryotes[1].
基金supported by grants from the National Natural Science Foundation of China(grant numbers 31760316,31600667,and 31871326)Priming Scientific Research Foundation of Hainan University(grant number KYQD(ZR)1721)Science Foundation for The Youth Teachers of Hainan University in 2017(grant number hdkyxj201702).
文摘Eukaryotic DNA methylation has been receiving increasing attention for its crucial epigenetic regulatory function.The recently developed single-molecule real-time(SMRT)sequencing technology provides an efficient way to detect DNA N6-methyladenine(6mA)and N4-methylcytosine(4mC)modifications at a single-nucleotide resolution.The family Rosaceae contains horticultural plants with a wide range of economic importance.However,little is currently known regarding the genome-wide distribution patterns and functions of 6mA and 4mC modifications in the Rosaceae.In this study,we present an integrated DNA 6mA and 4mC modification database for the Rosaceae(MDR,http://mdr.xieslab.org).MDR,the first repository for displaying and storing DNA 6mA and 4mC methylomes from SMRT sequencing data sets for Rosaceae,includes meta and statistical information,methylation densities,Gene Ontology enrichment analyses,and genome search and browse for methylated sites in NCBI.MDR provides important information regarding DNA 6mA and 4mC methylation and may help users better understand epigenetic modifications in the family Rosaceae.
文摘BACKGROUND There is no established treatment to impede the progression or restore kidney function in human chronic kidney disease(CKD).AIM To examine the efficacy of cultured human CD34+cells with enhanced proliferating potential in kidney injury in mice.METHODS Human umbilical cord blood(UCB)-derived CD34+cells were incubated for one week in vasculogenic conditioning medium.Vasculogenic culture significantly increased the number of CD34+cells and their ability to form endothelial progenitor cell colony-forming units.Adenineinduced tubulointerstitial injury of the kidney was induced in immunodeficient non-obese diabetic/severe combined immunodeficiency mice,and cultured human UCB-CD34+cells were administered at a dose of 1×106/mouse on days 7,14,and 21 after the start of adenine diet.RESULTS Repetitive administration of cultured UCB-CD34+cells significantly improved the time-course of kidney dysfunction in the cell therapy group compared with that in the control group.Both interstitial fibrosis and tubular damage were significantly reduced in the cell therapy group compared with those in the control group(P<0.01).Microvasculature integrity was significantly preserved(P<0.01)and macrophage infiltration into kidney tissue was dramatically decreased in the cell therapy group compared with those in the control group(P<0.001).CONCLUSION Early intervention using human cultured CD34+cells significantly improved the progression of tubulointerstitial kidney injury.Repetitive administration of cultured human UCB-CD34+cells significantly improved tubulointerstitial damage in adenine-induced kidney injury in mice via vasculoprotective and anti-inflammatory effects.