title: Spironolactone promotes autophagy via inhibiting PI3K/AKT/mTOR signalling pathway and reduce adhesive capacity damage in podocytes under mechanical stress.
abstract: Mechanical stress which would cause deleterious adhesive effects on podocytes is considered a major contributor to the early progress of diabetic nephropathy (DN). Our previous study has shown that spironolactone could ameliorate podocytic adhesive capacity in diabetic rats. Autophagy has been reported to have a protective role against renal injury. The present study investigated the underlying mechanisms by which spironolactone reduced adhesive capacity damage in podocytes under mechanical stress, focusing on the involvement of autophagy. Human conditional immortalized podocytes exposed to mechanical stress were treated with spironolactone, LY294002 or rapamycin for 48 h. The accumulation of LC3 puncta was detected by immunofluorescence staining. Podocyte expression of mineralocorticoid receptor (MR), integrin β1, LC3, Atg5, p85-PI3K, p-Akt, p-mTOR were detected by Western blotting. Podocyte adhesion to collagen type IV was also performed with spectrophotometry. Immunofluorescence staining showed that the normal level of autophagy was reduced in podocytes under mechanical stress. Decreased integrin β1, LC3, Atg5 and abnormal activation of the PI3K/Akt/mTOR pathway were also detected in podocytes under mechanical stress. Spironolactone up-regulated integrin β1, LC3, Atg5 expression, down-regulated p85-PI3K, p-Akt, p-mTOR expression and reduced podocytic adhesive capacity damage. Our data demonstrated that spironolactone inhibited mechanical-stress-induced podocytic adhesive capacity damage through blocking PI3K/Akt/mTOR pathway and restoring autophagy activity.
authors.affiliation: Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, 300052, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.affiliation: Tianjin Precell Biotechnology Co., Ltd., Huayuan Industrial District, Tianjin, 300384, P.R. China.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Lu
authors.affiliation: Central Laboratory, Logistics University of the Chinese People's Armed Police Force, Tianjin, 300309, China.
authors.forename: Zhongwei
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, 300052, China.
authors.forename: Junya
authors.initials: J
authors.lastname: Ji
authors.affiliation: Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, 300052, China.
authors.forename: Zhenfeng
authors.initials: Z
authors.lastname: Zheng
authors.affiliation: Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, 300052, China linshanmedmail@126.com tjtiekun@163.com.
authors.forename: Shan
authors.initials: S
authors.lastname: Lin
authors.affiliation: Department of Nephrology, General Hospital of Tianjin Medical University, Tianjin, 300052, China linshanmedmail@126.com tjtiekun@163.com.
authors.forename: Tiekun
authors.initials: T
authors.lastname: Yan
mesh_terms: D001343:Autophagy / Q000187:drug effects*; D000071187:Autophagy-Related Protein 5 / Q000378:metabolism; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D002867:Chromones / Q000494:pharmacology; D003928:Diabetic Nephropathies / Q000188:drug therapy / Q000378:metabolism; D015536:Down-Regulation / Q000187:drug effects; D006801:Humans; D019012:Integrin beta1 / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009025:Morpholines / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D050199:Podocytes / Q000187:drug effects* / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D018161:Receptors, Mineralocorticoid / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D020123:Sirolimus / Q000494:pharmacology; D013148:Spironolactone / Q000494:pharmacology*; D013314:Stress, Mechanical; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D000071187:Autophagy-Related Protein 5; D002867:Chromones; D019012:Integrin beta1; D008869:Microtubule-Associated Proteins; D009025:Morpholines; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt; D018161:Receptors, Mineralocorticoid; D020123:Sirolimus; D013148:Spironolactone; D058570:TOR Serine-Threonine Kinases; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C546842:MTOR protein, human
keywords: Atg5; diabetic nephropathy; integrin