Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties.In this study,we built the recombinant Bacillus subtilis WB800 expressing antimicrobial pepti...Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties.In this study,we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32(WB800-KR32)using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2(Nrf2)-Kelch-like ECH-associated protein 1(Keap1)pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli(ETEC)K88 in weaned piglets.Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet.The feed of the control group(CON)was infused with normal sterilized saline;meanwhile,the ETEC,ETEC+WB800,and ETEC+WB800-KR32 groups were orally administered normal sterilized saline,5×10^(10)CFU(CFU:colony forming units)WB800,and 5×10^(10)CFU WB800-KR32,respectively,on Days 1-14 and all infused with ETEC K881×10^(10)CFU on Days 15-17.The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance,improved the mucosal activity of antioxidant enzyme(catalase(CAT),superoxide dismutase(SOD),and glutathione peroxidase(GPx))and decreased the content of malondialdehyde(MDA).More importantly,WB800-KR32 downregulated genes involved in antioxidant defense(GPx and SOD1).Interestingly,WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum.WB800-KR32 markedly changed the richness estimators(Ace and Chao)of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces.The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway,providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.展开更多
Air pollution is fourth major cause of death worldwide.Recent evidence suggests that particulate matter(PM)may affect kidneys,and the effect may be size and composition dependent.In this study,PM_(0.1),PM_(2.5),and PM...Air pollution is fourth major cause of death worldwide.Recent evidence suggests that particulate matter(PM)may affect kidneys,and the effect may be size and composition dependent.In this study,PM_(0.1),PM_(2.5),and PM_(10)were collected from ambient air and given to BALB/c male mice at 0.25 mg/m^(3) concentration in whole-body inhalation chamber for 28days(6 h/day,5 days/week)to assess their effect on kidney.Physico-chemical characterization of PM particles by SEM,ICP-MS and HPLC showed their various shapes along with the presence of metals and poly aromatic hydrocarbons(PAHs).Following PM exposure,increased serum creatinine levels were observed in animals along with dilated tubules,protein cast deposition,necrosis,immune infiltration,collagen deposition,and shrunken glomeruli in kidney.Immunofluorescence staining showed higher expressions of kidney injury molecule1(KIM-1),cystatin C,β2 microglobulin(β2M),and alpha smooth muscle actin(α-SMA)and fibronectin,suggesting renal injury and fibrosis.PM exposure also increased malondialdehyde(MDA)content and decreased superoxide dismutase 2(SOD2)activity,which in turn leads to induction of inflammation.Mechanistically,PM exposure further inhibited the nuclear factor erythroid 2-related factor 2(Nrf2)signalling and induced kelch-like ECH-associated protein 1(Keap1)and nuclear factor kappa-light-chain-enhancer of activated B(NF-κB).Interestingly,the effect of PM_(2.5)was more severe than PM_(0.1)and PM_(10),leading to higher levels of proinflammatory NF-κB and greater Nrf2 inhibition.Overall,our findings suggested that inhalation exposure to size-segregated PM can cause kidney damage and fibrosis,and PM_(2.5)showed higher toxicity than PM_(0.1)and PM_(10).展开更多
Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for ...Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for the induction of diabetic retinopathy in rats.Rats received oral administration of shikonin(10,20,and 30 mg/kg).The blood glucose level,insulin,body weight,and organ weight were estimated.Advanced glycation end products(AGEs)levels in serum and lens as well as protein carbonyl content of the lens were determined.The parameters related to oxidative stress and inflammation,and the levels of nuclear factor erythroid 2-related factor 2(Nrf2),heme oxygenase-1(HO-1),intercellular adhesion molecule-1(ICAM-1),and vascular cell adhesion molecule 1(VCAM-1)were also measured.In addition,quantitative RT-PCR was performed to determine the mRNA expressions.Results:Shikonin treatment decreased glucose level and boosted insulin level,along with an increase in body weight and improved organ weight.It also lowered O2•−,ONOO−,serum and lens AGEs,and protein carbonyl content.Furthermore,shikonin treatment significantly alleviated oxidative stress and inflammation,as evidenced by reduced malonaldehyde,nitric oxide,tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,cyclooxygenase-2,prostaglandin E2,protein carbonyl content,and nuclear factor kappa-B,and increased superoxide dismutase,glutathione,catalase,and glutathione peroxidase.Markedly decreased levels of ICAM-1 and VCAM-1,as well as heightened levels of Nrf2 and HO-1,were noticed after treatment with shikonin.Furthermore,the mRNA expressions of TNF-α,IL-1β,IL-6,ICAM-1,VCAM-1,RAGE,collagenⅣ,and fibronectin were significantly downregulated.Conclusions:Shikonin exhibits protective effects against STZ-induced diabetic retinopathy in rats via modulating the Nrf2/HO-1 and NF-κB signaling pathways.展开更多
The aim of the present study was to investigate the protective effects and underlying mechanisms of Garcinia xanthochymus, a perennial medicinal plant native to Yunnan, China, against H2 O2-induced oxidative damage in...The aim of the present study was to investigate the protective effects and underlying mechanisms of Garcinia xanthochymus, a perennial medicinal plant native to Yunnan, China, against H2 O2-induced oxidative damage in rat pheochromacytoma PC12 cells. Preincubation of PC12 cells with fruit Et OAc fraction(fruit-EFr., 12.5–50 μmol·L^(-1)) of G. xanthochymus for 24 h prior to H_2O_2 exposure markedly improved cell viability and increased the activities of antioxidant enzymes(superoxide dismutase, catalase, and heme oxygenase-1 [HO-1]), prevented lactate dehydrogenase release and lipid peroxidation malondialdehyde production, attenuated the decrease of matrix metalloproteinases(MMP), and scavenged reactive oxygen species(ROS). Fruit-EFr. also reduced BAX and cytochrome C expression and improved BCL-2 expression, thereby decreasing the ratio of BAX to BCL-2. Fruit-EFr. activated the nuclear translocation of NRF2 to increase HO-1 and induced the phosphorylation of AKT. Its cytoprotective effect was abolished by LY294002, a specific inhibitor of PI3 K. Taken together, the above findings suggested that fruit-EFr.of G. xanthochymus could enhance cellular antioxidant defense capacity, at least in part, through upregulating HO-1 expression and activating the PI3 K/AKT pathway and that it could suppress H_2O_2-induced oxidative damage via PI3 K/AKT and NRF2/HO-1 signaling pathways.展开更多
基金supported by the Zhejiang Provincial Key R&D Program of China(No.2021C02008)the China Agriculture Research System of MOF and MARA(No.CARS-35)+2 种基金the National Natural Science Foundation of China(No.32022079)the Fundamental Research Funds for the Central Universities(No.2022QZJH46)the Taishan Industrial Leading Talents Project.
文摘Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties.In this study,we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32(WB800-KR32)using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2(Nrf2)-Kelch-like ECH-associated protein 1(Keap1)pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli(ETEC)K88 in weaned piglets.Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet.The feed of the control group(CON)was infused with normal sterilized saline;meanwhile,the ETEC,ETEC+WB800,and ETEC+WB800-KR32 groups were orally administered normal sterilized saline,5×10^(10)CFU(CFU:colony forming units)WB800,and 5×10^(10)CFU WB800-KR32,respectively,on Days 1-14 and all infused with ETEC K881×10^(10)CFU on Days 15-17.The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance,improved the mucosal activity of antioxidant enzyme(catalase(CAT),superoxide dismutase(SOD),and glutathione peroxidase(GPx))and decreased the content of malondialdehyde(MDA).More importantly,WB800-KR32 downregulated genes involved in antioxidant defense(GPx and SOD1).Interestingly,WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum.WB800-KR32 markedly changed the richness estimators(Ace and Chao)of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces.The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway,providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.
基金supported by the institutional fund MLP004 and Science and Engineering Research Board(SERB)(No.CRG/2021/002625)financial assistance from DBT-JRF,Department of Biotechnology,Gov of India,New Delhi India(DBT/2018/1111)。
文摘Air pollution is fourth major cause of death worldwide.Recent evidence suggests that particulate matter(PM)may affect kidneys,and the effect may be size and composition dependent.In this study,PM_(0.1),PM_(2.5),and PM_(10)were collected from ambient air and given to BALB/c male mice at 0.25 mg/m^(3) concentration in whole-body inhalation chamber for 28days(6 h/day,5 days/week)to assess their effect on kidney.Physico-chemical characterization of PM particles by SEM,ICP-MS and HPLC showed their various shapes along with the presence of metals and poly aromatic hydrocarbons(PAHs).Following PM exposure,increased serum creatinine levels were observed in animals along with dilated tubules,protein cast deposition,necrosis,immune infiltration,collagen deposition,and shrunken glomeruli in kidney.Immunofluorescence staining showed higher expressions of kidney injury molecule1(KIM-1),cystatin C,β2 microglobulin(β2M),and alpha smooth muscle actin(α-SMA)and fibronectin,suggesting renal injury and fibrosis.PM exposure also increased malondialdehyde(MDA)content and decreased superoxide dismutase 2(SOD2)activity,which in turn leads to induction of inflammation.Mechanistically,PM exposure further inhibited the nuclear factor erythroid 2-related factor 2(Nrf2)signalling and induced kelch-like ECH-associated protein 1(Keap1)and nuclear factor kappa-light-chain-enhancer of activated B(NF-κB).Interestingly,the effect of PM_(2.5)was more severe than PM_(0.1)and PM_(10),leading to higher levels of proinflammatory NF-κB and greater Nrf2 inhibition.Overall,our findings suggested that inhalation exposure to size-segregated PM can cause kidney damage and fibrosis,and PM_(2.5)showed higher toxicity than PM_(0.1)and PM_(10).
文摘Objective:To examine the effect of shikonin against streptozotocin(STZ)-induced diabetic retinopathy in rats and elucidate the underlying mechanisms.Methods:Intraperitoneal administration of STZ(65 mg/kg)was used for the induction of diabetic retinopathy in rats.Rats received oral administration of shikonin(10,20,and 30 mg/kg).The blood glucose level,insulin,body weight,and organ weight were estimated.Advanced glycation end products(AGEs)levels in serum and lens as well as protein carbonyl content of the lens were determined.The parameters related to oxidative stress and inflammation,and the levels of nuclear factor erythroid 2-related factor 2(Nrf2),heme oxygenase-1(HO-1),intercellular adhesion molecule-1(ICAM-1),and vascular cell adhesion molecule 1(VCAM-1)were also measured.In addition,quantitative RT-PCR was performed to determine the mRNA expressions.Results:Shikonin treatment decreased glucose level and boosted insulin level,along with an increase in body weight and improved organ weight.It also lowered O2•−,ONOO−,serum and lens AGEs,and protein carbonyl content.Furthermore,shikonin treatment significantly alleviated oxidative stress and inflammation,as evidenced by reduced malonaldehyde,nitric oxide,tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,cyclooxygenase-2,prostaglandin E2,protein carbonyl content,and nuclear factor kappa-B,and increased superoxide dismutase,glutathione,catalase,and glutathione peroxidase.Markedly decreased levels of ICAM-1 and VCAM-1,as well as heightened levels of Nrf2 and HO-1,were noticed after treatment with shikonin.Furthermore,the mRNA expressions of TNF-α,IL-1β,IL-6,ICAM-1,VCAM-1,RAGE,collagenⅣ,and fibronectin were significantly downregulated.Conclusions:Shikonin exhibits protective effects against STZ-induced diabetic retinopathy in rats via modulating the Nrf2/HO-1 and NF-κB signaling pathways.
基金supported by the National Natural Science Foundation of China(No.31370379)the National Natural Science Foundation Youth Project Financing(No.81201610)+1 种基金State Ethnic Affairs Commission Research Project(No.CMZY13012)Universities of Hubei Province Outstanding Youth Scientific Innovation Team Plan(No.T201220)
文摘The aim of the present study was to investigate the protective effects and underlying mechanisms of Garcinia xanthochymus, a perennial medicinal plant native to Yunnan, China, against H2 O2-induced oxidative damage in rat pheochromacytoma PC12 cells. Preincubation of PC12 cells with fruit Et OAc fraction(fruit-EFr., 12.5–50 μmol·L^(-1)) of G. xanthochymus for 24 h prior to H_2O_2 exposure markedly improved cell viability and increased the activities of antioxidant enzymes(superoxide dismutase, catalase, and heme oxygenase-1 [HO-1]), prevented lactate dehydrogenase release and lipid peroxidation malondialdehyde production, attenuated the decrease of matrix metalloproteinases(MMP), and scavenged reactive oxygen species(ROS). Fruit-EFr. also reduced BAX and cytochrome C expression and improved BCL-2 expression, thereby decreasing the ratio of BAX to BCL-2. Fruit-EFr. activated the nuclear translocation of NRF2 to increase HO-1 and induced the phosphorylation of AKT. Its cytoprotective effect was abolished by LY294002, a specific inhibitor of PI3 K. Taken together, the above findings suggested that fruit-EFr.of G. xanthochymus could enhance cellular antioxidant defense capacity, at least in part, through upregulating HO-1 expression and activating the PI3 K/AKT pathway and that it could suppress H_2O_2-induced oxidative damage via PI3 K/AKT and NRF2/HO-1 signaling pathways.
