PMID- 36760880 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20230211 IS - 2296-858X (Print) IS - 2296-858X (Electronic) IS - 2296-858X (Linking) VI - 9 DP - 2022 TI - Senescent renal tubular epithelial cells activate fibroblasts by secreting Shh to promote the progression of diabetic kidney disease. PG - 1018298 LID - 10.3389/fmed.2022.1018298 [doi] LID - 1018298 AB - INTRODUCTION: Diabetic kidney disease (DKD) is one of the complications of diabetes; however, the pathogenesis is not yet clear. A recent study has shown that senescence is associated with the course of DKD. In the present study, we explored whether senescent renal tubular cells promote renal tubulointerstitial fibrosis by secreting Sonic hedgehog (Shh) which mediates fibroblast activation and proliferation in DKD. METHODS: A 36-week-old db/db mice model and the renal tubular epithelial cells were cultured in high glucose (HG, 60 mmol/L) medium for in vivo and in vitro experiments. RESULTS: Compared to db/m mice, blood glucose, microalbuminuria, serum creatinine, urea nitrogen, and UACR (microalbuminuria/urine creatinine) were markedly increased in db/db mice. Collagen III, monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-alpha (TNF-alpha) were also increased in db/db mice kidneys, suggesting fibrosis and inflammation in the organ. Moreover, the detection of SA-beta-galactosidase (SA-beta-Gal) showed that the activity of SA-beta-Gal in the cytoplasm of renal tubular epithelial cells increased, and the cell cycle inhibition of the expression of senescence-related gene cell cycle inhibitor p16 (INK4A) protein and p21 protein increased, indicating that renal fibrosis in db/db mice was accompanied by cell senescence. Furthermore, Shh is highly expressed in the injured renal tubules and in the kidney tissue of db/db mice, as detected by enzyme-linked immunosorbent assay (ELISA). The results of immunofluorescence staining showed increased positive staining for Shh in renal tubular epithelial cells of db/db mice and decreased positive staining for Lamin B1, but increased positive staining for gammaH2A.X in cells with high Shh expression; similar results were obtained in vitro. In addition, HG stimulated renal tubular epithelial cells to secrete Shh in the supernatant of the medium. D-gal treatment of renal tubular epithelial cells increased the protein levels of Shh and p21. We also found enhanced activation and proliferation of fibroblasts cultured with the supernatant of renal tubular epithelial cells stimulated by HG medium but the proliferative effect was significantly diminished when co-cultured with cyclopamine (CPN), an inhibitor of the Shh pathway. DISCUSSION: In conclusion, HG induces renal tubular epithelial cell senescence, and the secretion of senescence-associated proteins and Shh mediates inflammatory responses and fibroblast activation and proliferation, ultimately leading to renal fibrosis. CI - Copyright (c) 2023 Wang, Yin, Chen, Tan, Liang, Xiang, Zhang, Zhou, Deng, Guo and Wang. FAU - Wang, Dan AU - Wang D AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. AD - International Scientific and Technological Cooperation Base of Pathogenesis and Drug Research on Common Major Diseases, Guizhou Medical University, Guiyang, China. FAU - Yin, Ling AU - Yin L AD - Division of Nephrology, Jiangsu Provincial Hospital of Chinese Medicine, Nanjing, Jiangsu, China. FAU - Chen, Rongyu AU - Chen R AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Tan, Wanlin AU - Tan W AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Liang, Luqun AU - Liang L AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Xiang, Jiayi AU - Xiang J AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Zhang, Huifang AU - Zhang H AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Zhou, Xingcheng AU - Zhou X AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Deng, Huaqing AU - Deng H AD - Department of Pathophysiology, School of Basic Medicine, Guizhou Medical University, Guiyang, China. AD - Guizhou Provincial Key Laboratory of Pathogenesis and Drug Research on Common Chronic Diseases, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Guo, Bing AU - Guo B AD - Guizhou Province Innovation Base of Common Major Chronic Disease Pathogenesis and Drug Development and Application, Guiyang, Guizhou, China. AD - Key Laboratory of Endemic and Ethnic Diseases, Ministry of Education, Guizhou Medical University, Guiyang, Guizhou, China. AD - Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China. FAU - Wang, Yuanyuan AU - Wang Y AD - International Scientific and Technological Cooperation Base of Pathogenesis and Drug Research on Common Major Diseases, Guizhou Medical University, Guiyang, China. AD - Guizhou Province Innovation Base of Common Major Chronic Disease Pathogenesis and Drug Development and Application, Guiyang, Guizhou, China. AD - Department of Pathophysiology, Guizhou Medical University, Guiyang, Guizhou, China. LA - eng PT - Journal Article DEP - 20230125 PL - Switzerland TA - Front Med (Lausanne) JT - Frontiers in medicine JID - 101648047 PMC - PMC9905119 OTO - NOTNLM OT - SASP OT - Shh OT - diabetic kidney disease OT - inflammation OT - renal tubular epithelial cells OT - senescence COIS- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. EDAT- 2023/02/11 06:00 MHDA- 2023/02/11 06:01 PMCR- 2023/01/25 CRDT- 2023/02/10 03:02 PHST- 2022/08/13 00:00 [received] PHST- 2022/12/08 00:00 [accepted] PHST- 2023/02/10 03:02 [entrez] PHST- 2023/02/11 06:00 [pubmed] PHST- 2023/02/11 06:01 [medline] PHST- 2023/01/25 00:00 [pmc-release] AID - 10.3389/fmed.2022.1018298 [doi] PST - epublish SO - Front Med (Lausanne). 2023 Jan 25;9:1018298. doi: 10.3389/fmed.2022.1018298. eCollection 2022.