The expression of serum and glucocorticoid-induced protein kinase in the renal cortex of diabetic rats was examined, and the function of signal transduction mediated by SGK1 in diabetic nephropathy and its modulation ...The expression of serum and glucocorticoid-induced protein kinase in the renal cortex of diabetic rats was examined, and the function of signal transduction mediated by SGK1 in diabetic nephropathy and its modulation by fluvastatin were also investigated. 24 male Wistar rats were randomly divided into normal control group （n = 8）, diabetic nephropathy group （n = 8） and fluvastatin-treated diabetic nephropathy group （15 mg/kg/d, n=8）. The metabolic parameters were measured at the 8th week. The expression of transforming growth factor β1 （TGF-β1） and fibronectin （FN） was immunohistochemically examined. The expression of SGK1 was detected by RT-PCR and Western blot, and CTGF mRNA was assessed by RT-PCR. As compared to DN, blood glucose, 24-h urinary protein, Cer and kidney weight index were all decreased and the weight was increased obviously in group F. At the same time, mesangial cells and extracellular matrix proliferation were relieved significantly. The levels of cortex SGK1 mRNA and protein were up-regulated, and both TGF-β1 and FN were down-regulated by fluvastatin. The mRNA of SGK1 was positively correlated with the CTGF, TGF-β1 and FN. SGK1 expression is markedly up-regulated in the renal cortex of DN group and plays an important role in the development and progress of diabetic nephropathy by means of signal transduction. Fluvastatin suppressed the increased SGKlmRNA expression in renal cortex and postponed the development of diabetic nephropathy.展开更多
Summary: To investigate the expression and the role of three isoforms of Serum and Glucocorticoid-inducible Kinase (SGK) in experimental diabetic nephropathy (DN), 12 male C57BL/6 mice of 8-weeks-old were divided into...Summary: To investigate the expression and the role of three isoforms of Serum and Glucocorticoid-inducible Kinase (SGK) in experimental diabetic nephropathy (DN), 12 male C57BL/6 mice of 8-weeks-old were divided into two groups. Streptozotocin (STZ)-induced diabetic nephropathy and normal controls were analyzed at the end of the 4th week after the induction of diabetes. Renal hemodynamics and histological studies were performed. The expression of SGK1 mRNA, SGK2 mRNA and SGK3 mRNA of kidney cortex were measured by RT-PCR, and the cortical SGK1 protein was detected with Western blotting. Our results showed that the blood glucose, blood HbA1c, 24-h urinary protein, creatinine clearance and the renal index were all increased in DN group. More extracellular matrix (ECM) accumulation was observed. The level of cortical SGK1 mRNA and protein were up-regulated in DN group in comparison with control group. SGK2 and SGK3 mRNA were elevated in DN mice. In DN, mRNA level of three SGK isoforms and SGK1 protein were increased significantly. It is concluded that SGKs may contribute to the early renal injury of DN.展开更多
As recent medical progress decreases the incidence of certain diseases, ischemic brain injury remains one of the major dis- eases that threaten human lives, especially in western countries. Ischemic brain injury occur...As recent medical progress decreases the incidence of certain diseases, ischemic brain injury remains one of the major dis- eases that threaten human lives, especially in western countries. Ischemic brain injury occurs as a result of lack of oxygen and nutrients due to obstruction of blood flow in the brain, and often leads to neurological disorders such as cerebral palsy, depression, and ultimately, death. Around 800,000 Americans suffer a new or recurrent stroke, and more than 130,000 people die annually in the United States （Goldstein et al., 2011）. Despite much effort in searching for an effective treatment, at most a few reagents are approved for therapeutic medication in many countries.展开更多
The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By usin...The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.展开更多
BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intesti...BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury.PTEN-induced putative kinase 1(PINK1)and phosphorylation of dynamin-related protein 1(DRP1)are critical regulators of ROS and apoptosis.However,the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated.Thus,examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis.AIM To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury.METHODS Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion.Chiu’s score was used to evaluate intestinal mucosa damage.The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection.Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions.Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression.The protein expression levels of PINK1,DRP1,p-DRP1 and cleaved caspase 3 were measured by Western blotting.Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining.Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively.RESULTS Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637.Pretreatment with mdivi-1 inhibited mitochondrial fission,ROS generation,and apoptosis and ameliorated cell injury in intestinal I/R.Upon PINK1 knockdown or overexpression in vitro,we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1.Furthermore,we verified the physical combination of PINK1 and p-DRP1 Ser637.CONCLUSION PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R.These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury,and provide a new approach for prevention and treatment.展开更多
BACKGROUND The expression status of serum and glucocorticoid-induced protein kinase 3(SGK3)in superficial esophageal squamous cell neoplasia(ESCN)remains unknown.AIM To evaluate the SGK3 overexpression rate in ESCN an...BACKGROUND The expression status of serum and glucocorticoid-induced protein kinase 3(SGK3)in superficial esophageal squamous cell neoplasia(ESCN)remains unknown.AIM To evaluate the SGK3 overexpression rate in ESCN and its influence on the prognosis and outcomes of patients with endoscopic resection.METHODS A total of 92 patients who had undergone endoscopic resection for ESCN with more than 8 years of follow-up were enrolled.Immunohistochemistry was used to evaluate SGK3 expression.RESULTS SGK3 was overexpressed in 55(59.8%)patients with ESCN.SGK3 overexpression showed a significant correlation with death(P=0.031).Overall survival and disease-free survival rates were higher in the normal SGK3 expression group than in the SGK3 overexpression group(P=0.013 and P=0.004,respectively).Cox regression analysis models demonstrated that SGK3 overexpression was an independent predictor of poor prognosis in ESCN patients(hazard ratio 4.729;95% confidence interval:1.042-21.458).CONCLUSION SGK3 overexpression was detected in the majority of patients with endoscopically resected ESCN and was significantly associated with shortened survival.Thus,it might be a new prognostic factor for ESCN.展开更多
文摘The expression of serum and glucocorticoid-induced protein kinase in the renal cortex of diabetic rats was examined, and the function of signal transduction mediated by SGK1 in diabetic nephropathy and its modulation by fluvastatin were also investigated. 24 male Wistar rats were randomly divided into normal control group （n = 8）, diabetic nephropathy group （n = 8） and fluvastatin-treated diabetic nephropathy group （15 mg/kg/d, n=8）. The metabolic parameters were measured at the 8th week. The expression of transforming growth factor β1 （TGF-β1） and fibronectin （FN） was immunohistochemically examined. The expression of SGK1 was detected by RT-PCR and Western blot, and CTGF mRNA was assessed by RT-PCR. As compared to DN, blood glucose, 24-h urinary protein, Cer and kidney weight index were all decreased and the weight was increased obviously in group F. At the same time, mesangial cells and extracellular matrix proliferation were relieved significantly. The levels of cortex SGK1 mRNA and protein were up-regulated, and both TGF-β1 and FN were down-regulated by fluvastatin. The mRNA of SGK1 was positively correlated with the CTGF, TGF-β1 and FN. SGK1 expression is markedly up-regulated in the renal cortex of DN group and plays an important role in the development and progress of diabetic nephropathy by means of signal transduction. Fluvastatin suppressed the increased SGKlmRNA expression in renal cortex and postponed the development of diabetic nephropathy.
基金This project was supported by a grant from the National Natural Sciences Foundation of China (No. 30270618).
文摘Summary: To investigate the expression and the role of three isoforms of Serum and Glucocorticoid-inducible Kinase (SGK) in experimental diabetic nephropathy (DN), 12 male C57BL/6 mice of 8-weeks-old were divided into two groups. Streptozotocin (STZ)-induced diabetic nephropathy and normal controls were analyzed at the end of the 4th week after the induction of diabetes. Renal hemodynamics and histological studies were performed. The expression of SGK1 mRNA, SGK2 mRNA and SGK3 mRNA of kidney cortex were measured by RT-PCR, and the cortical SGK1 protein was detected with Western blotting. Our results showed that the blood glucose, blood HbA1c, 24-h urinary protein, creatinine clearance and the renal index were all increased in DN group. More extracellular matrix (ECM) accumulation was observed. The level of cortical SGK1 mRNA and protein were up-regulated in DN group in comparison with control group. SGK2 and SGK3 mRNA were elevated in DN mice. In DN, mRNA level of three SGK isoforms and SGK1 protein were increased significantly. It is concluded that SGKs may contribute to the early renal injury of DN.
文摘As recent medical progress decreases the incidence of certain diseases, ischemic brain injury remains one of the major dis- eases that threaten human lives, especially in western countries. Ischemic brain injury occurs as a result of lack of oxygen and nutrients due to obstruction of blood flow in the brain, and often leads to neurological disorders such as cerebral palsy, depression, and ultimately, death. Around 800,000 Americans suffer a new or recurrent stroke, and more than 130,000 people die annually in the United States （Goldstein et al., 2011）. Despite much effort in searching for an effective treatment, at most a few reagents are approved for therapeutic medication in many countries.
基金a grant from the National Natural Sciences Foundation of China (No. 30600810)
文摘The role of serum and glucocorticoid-induced kinase 1 （SGK1） pathway in the connective tissue growth factor （CTGF） expression was investigated in cultured human mesangial cells （HMCs） under high glucose. By using RT-PCR and Western blot, the effect of SGK1 on the CTGF expression in HMCs under high glucose was examined. Overexpression of active SGK1 in HMCs transfected with PIRES2-EGFP- S422D hSGK1 （SD） could increase the expression of phosphorylated SGK1 and CTGF as compared with HMCs groups transfected with PIRES2-EGFP （FP） under high glucose or normal glucose. Overexpression of inactive SGK1 in HMCs transfected with PIRES2-EGFP- K127N hSGK1 （KN） could decrease phosphorylated SGK1 and CTGF expression as compared with HMCs groups transfected with FP under high glucose. In conclusion, these results suggest that high glucose-induced CTGF expression is mediated through the active SGK1 in HMCs.
基金the National Natural Science Foundation of China,No.81679154,No.81871547.
文摘BACKGROUND Intestinal ischemia reperfusion(I/R)occurs in various diseases,such as trauma and intestinal transplantation.Excessive reactive oxygen species(ROS)accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury.PTEN-induced putative kinase 1(PINK1)and phosphorylation of dynamin-related protein 1(DRP1)are critical regulators of ROS and apoptosis.However,the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated.Thus,examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis.AIM To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury.METHODS Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion.Chiu’s score was used to evaluate intestinal mucosa damage.The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection.Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions.Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression.The protein expression levels of PINK1,DRP1,p-DRP1 and cleaved caspase 3 were measured by Western blotting.Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining.Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively.RESULTS Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637.Pretreatment with mdivi-1 inhibited mitochondrial fission,ROS generation,and apoptosis and ameliorated cell injury in intestinal I/R.Upon PINK1 knockdown or overexpression in vitro,we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1.Furthermore,we verified the physical combination of PINK1 and p-DRP1 Ser637.CONCLUSION PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R.These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury,and provide a new approach for prevention and treatment.
基金Supported by National Natural Science Foundation of China,No.82070682Beijing Municipal Science and Technology Commission,China,No.Z181100001718177.
文摘BACKGROUND The expression status of serum and glucocorticoid-induced protein kinase 3(SGK3)in superficial esophageal squamous cell neoplasia(ESCN)remains unknown.AIM To evaluate the SGK3 overexpression rate in ESCN and its influence on the prognosis and outcomes of patients with endoscopic resection.METHODS A total of 92 patients who had undergone endoscopic resection for ESCN with more than 8 years of follow-up were enrolled.Immunohistochemistry was used to evaluate SGK3 expression.RESULTS SGK3 was overexpressed in 55(59.8%)patients with ESCN.SGK3 overexpression showed a significant correlation with death(P=0.031).Overall survival and disease-free survival rates were higher in the normal SGK3 expression group than in the SGK3 overexpression group(P=0.013 and P=0.004,respectively).Cox regression analysis models demonstrated that SGK3 overexpression was an independent predictor of poor prognosis in ESCN patients(hazard ratio 4.729;95% confidence interval:1.042-21.458).CONCLUSION SGK3 overexpression was detected in the majority of patients with endoscopically resected ESCN and was significantly associated with shortened survival.Thus,it might be a new prognostic factor for ESCN.
