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Li Z, Zhao J, Wu Y, Fan S, Yuan H, Xia J, Hu L, Yang J, Liu J, Wu X, Lin R, Yang L. TRAF2 decrease promotes the TGF-β-mTORC1 signal in MAFLD-HCC through enhancing AXIN1-mediated Smad7 degradation. FASEB J 2024; 38:e23491. [PMID: 38363556 DOI: 10.1096/fj.202302307r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 01/13/2024] [Accepted: 02/01/2024] [Indexed: 02/17/2024]
Abstract
According to recent research, metabolic-associated fatty liver disease (MAFLD) has emerged as an important underlying etiology of hepatocellular carcinoma (HCC). However, the molecular mechanism of MAFLD-HCC is still unclear. Tumor necrosis factor receptor-associated factor 2 (TRAF2) is the key molecule to mediate the signal of inflammatory NF-κB pathway. This study aims to investigate the potential dysregulation of TRAF2 and its biological function in MAFLD-HCC. Huh7 TRAF2-/- demonstrated increased tumor formation ability compared to huh7 TRAF2+/+ when stimulated with transforming growth factor-β (TGF-β). The decisive role of TGF-β in the development of MAFLD-HCC was confirmed through the specific depletion of TGF-β receptor II gene in the hepatocytes (Tgfbr2ΔHep) of mice. In TRAF2-/- cells treated with TGF-β, both the glycolysis rate and lipid synthesis were enhanced. We proved the signal of the mechanistic target of rapamycin complex 1 (mTORC1) could be activated in the presence of TGF-β, and was enhanced in TRAF2-/- cells. The coimmunoprecipitation (co-IP) experiments revealed that TRAF2 fortified the Smurf2-mediated ubiquitination degradation of AXIN1. Hence, TRAF2 depletion resulted in increased Smad7 degradation induced by AXIN1, thus promoting the TGF-β signal. We also discovered that PLX-4720 could bind with AXIN1 and restrained the tumor proliferation of TRAF2-/- in mice fed with high-fat diet (HFD). Our findings indicate that TRAF2 plays a significant role in the pathogenesis of MAFLD-HCC. The reduction of TRAF2 expression leads to the enhancement of the TGF-β-mTORC1 pathway by facilitating AXIN1-mediated Smad7 degradation.
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Affiliation(s)
- Zhonglin Li
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jinfang Zhao
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ya Wu
- Institute of Resource Biology and Biotechnology, Department of Biotechnology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, China
| | - Siyuan Fan
- Cardiovascular Medicine Department, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hang Yuan
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Xia
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lilin Hu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jingze Yang
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiazheng Liu
- State Key Laboratory of Quality Research in Chinese Medicine, Macau Institute for Applied Research in Medicine and Health, Macau University of Science and Technology, Taipa, Macau, China
| | - Xuefeng Wu
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Rong Lin
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ling Yang
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Zhang YX, Lv J, Bai JY, Pu X, Dai EL. Identification of key biomarkers of the glomerulus in focal segmental glomerulosclerosis and their relationship with immune cell infiltration based on WGCNA and the LASSO algorithm. Ren Fail 2023; 45:2202264. [PMID: 37096442 PMCID: PMC10132234 DOI: 10.1080/0886022x.2023.2202264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/26/2023] Open
Abstract
OBJECTIVE The aim of our study was to identify key biomarkers of glomeruli in focal glomerulosclerosis (FSGS) and analyze their relationship with the infiltration of immune cells. METHODS The expression profiles (GSE108109 and GSE200828) were obtained from the GEO database. The differentially expressed genes (DEGs) were filtered and analyzed by gene set enrichment analysis (GSEA). MCODE module was constructed. Weighted gene coexpression network analysis (WGCNA) was performed to obtain the core gene modules. Least absolute shrinkage and selection operator (LASSO) regression was applied to identify key genes. ROC curves were employed to explore their diagnostic accuracy. Transcription factor prediction of the key biomarkers was performed using the Cytoscape plugin IRegulon. The analysis of the infiltration of 28 immune cells and their correlation with the key biomarkers were performed. RESULTS A total of 1474 DEGs were identified. Their functions were mostly related to immune-related diseases and signaling pathways. MCODE identified five modules. The turquoise module of WGCNA had significant relevance to the glomerulus in FSGS. TGFB1 and NOTCH1 were identified as potential key glomerular biomarkers in FSGS. Eighteen transcription factors were obtained from the two hub genes. Immune infiltration showed significant correlations with T cells. The results of immune cell infiltration and their relationship with key biomarkers implied that NOTCH1 and TGFB1 were enhanced in immune-related pathways. CONCLUSION TGFB1 and NOTCH1 may be strongly correlated with the pathogenesis of the glomerulus in FSGS and are new candidate key biomarkers. T-cell infiltration plays an essential role in the FSGS lesion process.
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Affiliation(s)
- Yun Xia Zhang
- College of Integrated Traditional and Western Medicine, Gansu University of Traditional Chinese Medicine, Lanzhou, China
- Gansu Provincial Hospital of Traditional Chinese Medicine, Lanzhou, China
| | - Juan Lv
- College of Integrated Traditional and Western Medicine, Gansu University of Traditional Chinese Medicine, Lanzhou, China
- Gansu Provincial Hospital of Traditional Chinese Medicine, Lanzhou, China
| | - Jun Yuan Bai
- College of Integrated Traditional and Western Medicine, Gansu University of Traditional Chinese Medicine, Lanzhou, China
- Affiliated Hospital of Gansu University of Chinese Medicine, Lanzhou, China
| | - XiaoWei Pu
- College of Integrated Traditional and Western Medicine, Gansu University of Traditional Chinese Medicine, Lanzhou, China
| | - En Lai Dai
- College of Integrated Traditional and Western Medicine, Gansu University of Traditional Chinese Medicine, Lanzhou, China
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Chhuon C, Herrera-Marcos LV, Zhang SY, Charrière-Bertrand C, Jung V, Lipecka J, Savas B, Nasser N, Pawlak A, Boulmerka H, Audard V, Sahali D, Guerrera IC, Ollero M. Proteomics of Plasma and Plasma-Treated Podocytes: Application to Focal and Segmental Glomerulosclerosis. Int J Mol Sci 2023; 24:12124. [PMID: 37569500 PMCID: PMC10418338 DOI: 10.3390/ijms241512124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/21/2023] [Accepted: 07/26/2023] [Indexed: 08/13/2023] Open
Abstract
Focal and segmental glomerulosclerosis (FSGS) is a severe form of idiopathic nephrotic syndrome (INS), a glomerulopathy of presumably immune origin that is attributed to extrarenal pathogenic circulating factors. The recurrence of FSGS (rFSGS) after transplant occurs in 30% to 50% of cases. The direct analysis of patient plasma proteome has scarcely been addressed to date, mainly due to the methodological difficulties associated with plasma complexity and dynamic range. In this study, first, we compared different methods of plasma preparation, second, we compared the plasma proteomes of rFSGS and controls using two preparation methods, and third, we analyzed the early proximal signaling events in podocytes subjected to patient plasma, through a combination of phosphoproteomics and lipid-raft proteomics (raftomics). By combining immunodepletion and high pH fractionation, we performed a differential proteomic analysis of soluble plasma proteins and of extracellular vesicles (EV) obtained from healthy controls, non-INS patient controls, and rFSGS patients (n = 4). In both the soluble- and the EV-protein sets from the rFSGS patients, we found a statistically significant increase in a cluster of proteins involved in neutrophil degranulation. A group of lipid-binding proteins, generally associated with lipoproteins, was found to be decreased in the soluble set from the rFSGS patients. In addition, three amino acid transporters involved in mTORC1 activation were found to be significantly increased in the EV from the rFSGS. Next, we incubated human podocytes for 30 min with 10% plasma from both groups of patients. The phosphoproteomics and raftomics of the podocytes revealed profound differences in the proteins involved in the mTOR pathway, in autophagy, and in cytoskeleton organization. We analyzed the correlation between the abundance of plasma and plasma-regulated podocyte proteins. The observed changes highlight some of the mechanisms involved in FSGS recurrence and could be used as specific early markers of circulating-factor activity in podocytes.
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Affiliation(s)
- Cerina Chhuon
- Proteomic Platform Necker, Université Paris Cité Structure Fédérative de Recherche SFR Necker US24, 75015 Paris, France; (C.C.); (V.J.); (J.L.)
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Luis Vicente Herrera-Marcos
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Shao-Yu Zhang
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Cécile Charrière-Bertrand
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Vincent Jung
- Proteomic Platform Necker, Université Paris Cité Structure Fédérative de Recherche SFR Necker US24, 75015 Paris, France; (C.C.); (V.J.); (J.L.)
| | - Joanna Lipecka
- Proteomic Platform Necker, Université Paris Cité Structure Fédérative de Recherche SFR Necker US24, 75015 Paris, France; (C.C.); (V.J.); (J.L.)
| | - Berkan Savas
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Nour Nasser
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - André Pawlak
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Hocine Boulmerka
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
| | - Vincent Audard
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
- AP-HP, Hôpitaux Universitaires Henri Mondor, Service de Néphrologie, F-94010 Creteil, France
| | - Dil Sahali
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
- AP-HP, Hôpitaux Universitaires Henri Mondor, Service de Néphrologie, F-94010 Creteil, France
| | - Ida Chiara Guerrera
- Proteomic Platform Necker, Université Paris Cité Structure Fédérative de Recherche SFR Necker US24, 75015 Paris, France; (C.C.); (V.J.); (J.L.)
| | - Mario Ollero
- Univ Paris Est Creteil, INSERM, IMRB, F-94010 Creteil, France; (L.V.H.-M.); (S.-Y.Z.); (C.C.-B.); (B.S.); (N.N.); (A.P.); (H.B.); (V.A.); (D.S.)
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Hirata T, Ohara H, Kojima N, Koretsune H, Hasegawa Y, Inatani S, Takahashi T. Renoprotective Effect of TP0472993, a Novel and Selective 20-Hydroxyeicosatetraenoic Acid Synthesis Inhibitor, in Mouse Models of Renal Fibrosis. J Pharmacol Exp Ther 2023; 386:56-69. [PMID: 37142440 DOI: 10.1124/jpet.122.001521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 04/06/2023] [Accepted: 04/17/2023] [Indexed: 05/06/2023] Open
Abstract
Kidney fibrosis is considered the essential pathophysiological process for the progression of chronic kidney disease (CKD) toward renal failure. 20-Hydroxyeicosatetraenoic acid (20-HETE) has crucial roles in modulating the vascular response in the kidney and the progression of albuminuria. However, the roles of 20-HETE in kidney fibrosis are largely unexplored. In the current research, we hypothesized that if 20-HETE has important roles in the progression of kidney fibrosis, 20-HETE synthesis inhibitors might be effective against kidney fibrosis. To verify our hypothesis, this study investigated the effect of a novel and selective 20-HETE synthesis inhibitor, TP0472993, on the development of kidney fibrosis after folic acid- and obstructive-induced nephropathy in mice. Chronic treatment with TP0472993 at doses of 0.3 and 3 mg/kg twice a day attenuated the degree of kidney fibrosis in the folic acid nephropathy and the unilateral ureteral obstruction (UUO) mice, as demonstrated by reductions in Masson's trichrome staining and the renal collagen content. In addition, TP0472993 reduced renal inflammation, as demonstrated by markedly reducing interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNF-α) levels in the renal tissue. Chronic treatment with TP0472993 also reduced the activity of extracellular signal-regulated kinase 1/2 (ERK1/2) and signal transducer and activator of transcription 3 (STAT3) in the kidney of UUO mice. Our observations indicate that inhibition of 20-HETE production with TP0472993 suppresses the kidney fibrosis progression via a reduction in the ERK1/2 and STAT3 signaling pathway, suggesting that 20-HETE synthesis inhibitors might be a novel treatment option against CKD. SIGNIFICANCE STATEMENT: In this study, we demonstrate that the pharmacological blockade of 20-hydroxyeicosatetraenoic acid (20-HETE) synthesis using TP0472993 suppresses the progression of kidney fibrosis after folic acid- and obstructive-induced nephropathy in mice, indicating that 20-HETE might have key roles in the pathogenesis of kidney fibrosis. TP0472993 has the potential to be a novel therapeutic approach against chronic kidney disease.
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Affiliation(s)
- Takashi Hirata
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Hiroki Ohara
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Naoki Kojima
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Hiroko Koretsune
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Yoshitaka Hasegawa
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Shoko Inatani
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
| | - Teisuke Takahashi
- Pharmacology Laboratories (T.H., H.O., N.K., H.K., T.T.) and Drug Safety and Pharmacokinetics Laboratories (Y.H., S.I.), Taisho Pharmaceutical Co., Ltd., Saitama, Japan
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Dong J, Zheng F, Liu F, He J, Li S, Pu W, Xu H, Luo Z, Liu S, Yin L, Tang D, Dai Y. Global-feature of autoimmune glomerulonephritis using proteomic analysis of laser capture microdissected glomeruli. Front Immunol 2023; 14:1131164. [PMID: 37033921 PMCID: PMC10077062 DOI: 10.3389/fimmu.2023.1131164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 02/13/2023] [Indexed: 04/11/2023] Open
Abstract
Background IgA nephropathy (IgAN), (LN), membranous nephropathy (MN), and minimal change nephropathy (MCN) are all belonged to autoimmune glomerulonephritis. This study aimed to identify the specific proteomic characteristics of the four GNs diseases in order to provide frameworks for developing the appropriate drug for patients diagnosed with GNs disease. Methods Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was utilized to investigate proteomic features of glomerular tissues obtained by laser capture microdissection (LCM). 8 normal control cases, 11 IgAN cases, 19 LN cases, 5 MN cases, and 3 MCN cases in this study were selected for bioinformatics analyses. Results The shared overlapping proteins among the top 100 DEPs of each GNs type were mostly downregulated, in which only FLII was significantly downregulated in the four GNs diseases. A2M was significantly upregulated in MN, IgAN, and LN subgroups. The pathway of complement and coagulation cascades was notably activated with NES value ranging 2.77 to 3.39 among MCN, MN, IgAN, and LN diseases, but the pattern of protein expression level were significantly different. In LN patients, the increased activity of complement and coagulation cascades was contributed by the high expression of multiple complements (C1QB, C3, C4A, C4B, C6, C8B, C8G, C9). Meanwhile, both C1QC and C4B were remarkably upregulated in MN patients. On the contrary, complement-regulating proteins (CD59) was substantially decreased in MCN and IgAN subgroup. Conclusions The integrative proteomics analysis of the four GNs diseases provide insights into unique characteristics of GNs diseases and further serve as frameworks for precision medicine diagnosis and provide novel targets for drug development.
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Affiliation(s)
- Jingjing Dong
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
- Institute of Nephrology and Blood Purification, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Fengping Zheng
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
- Department of Nephrology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, Guangdong, China
| | - Fanna Liu
- Institute of Nephrology and Blood Purification, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Jingquan He
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
| | - Shanshan Li
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
| | - Wenjun Pu
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
| | - Huixuan Xu
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
| | - Zhifeng Luo
- Guangxi Key Laboratory of Metabolic Disease Research, The 924th Hospital of the Chinese People’s Liberation Army Joint Logistic Support Force, Guilin, Guangxi, China
| | - Shizhen Liu
- Institute of Nephrology and Blood Purification, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
| | - Lianghong Yin
- Institute of Nephrology and Blood Purification, The First Affiliated Hospital of Jinan University, Jinan University, Guangzhou, China
- *Correspondence: Lianghong Yin, ; Donge Tang, ; Yong Dai,
| | - Donge Tang
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
- *Correspondence: Lianghong Yin, ; Donge Tang, ; Yong Dai,
| | - Yong Dai
- Clinical Medical Research Center, The Second Clinical Medical College of Jinan University, Shenzhen People’s Hospital, Shenzhen, Guangdong, China
- Guangxi Key Laboratory of Metabolic Disease Research, The 924th Hospital of the Chinese People’s Liberation Army Joint Logistic Support Force, Guilin, Guangxi, China
- *Correspondence: Lianghong Yin, ; Donge Tang, ; Yong Dai,
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Nakano T, Watanabe H, Imafuku T, Tokumaru K, Fujita I, Arimura N, Maeda H, Tanaka M, Matsushita K, Fukagawa M, Maruyama T. Indoxyl Sulfate Contributes to mTORC1-Induced Renal Fibrosis via The OAT/NADPH Oxidase/ROS Pathway. Toxins (Basel) 2021; 13:toxins13120909. [PMID: 34941746 PMCID: PMC8706756 DOI: 10.3390/toxins13120909] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/14/2021] [Accepted: 12/17/2021] [Indexed: 12/26/2022] Open
Abstract
Activation of mTORC1 (mechanistic target of rapamycin complex 1) in renal tissue has been reported in chronic kidney disease (CKD)-induced renal fibrosis. However, the molecular mechanisms responsible for activating mTORC1 in CKD pathology are not well understood. The purpose of this study was to identify the uremic toxin involved in mTORC1-induced renal fibrosis. Among the seven protein-bound uremic toxins, only indoxyl sulfate (IS) caused significant activation of mTORC1 in human kidney 2 cells (HK-2 cells). This IS-induced mTORC1 activation was inhibited in the presence of an organic anion transporter inhibitor, a NADPH oxidase inhibitor, and an antioxidant. IS also induced epithelial–mesenchymal transition of tubular epithelial cells (HK-2 cells), differentiation of fibroblasts into myofibroblasts (NRK-49F cells), and inflammatory response of macrophages (THP-1 cells), which are associated with renal fibrosis, and these effects were inhibited in the presence of rapamycin (mTORC1 inhibitor). In in vivo experiments, IS overload was found to activate mTORC1 in the mouse kidney. The administration of AST-120 or rapamycin targeted to IS or mTORC1 ameliorated renal fibrosis in Adenine-induced CKD mice. The findings reported herein indicate that IS activates mTORC1, which then contributes to renal fibrosis. Therapeutic interventions targeting IS and mTORC1 could be effective against renal fibrosis in CKD.
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Affiliation(s)
- Takehiro Nakano
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Hiroshi Watanabe
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
- Correspondence: ; Tel.: +81-96-371-4855
| | - Tadashi Imafuku
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Kai Tokumaru
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Issei Fujita
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Nanaka Arimura
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Hitoshi Maeda
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
| | - Motoko Tanaka
- Department of Nephrology, Akebono Clinic, Kumamoto 8614112, Japan; (M.T.); (K.M.)
| | - Kazutaka Matsushita
- Department of Nephrology, Akebono Clinic, Kumamoto 8614112, Japan; (M.T.); (K.M.)
| | - Masafumi Fukagawa
- Division of Nephrology, Endocrinology and Metabolism, Tokai University School of Medicine, Kanagawa 2591193, Japan;
| | - Toru Maruyama
- Department of Biopharmaceutics, Graduate School of Pharmaceutical Sciences, Kumamoto University, Kumamoto 8620973, Japan; (T.N.); (T.I.); (K.T.); (I.F.); (N.A.); (H.M.); (T.M.)
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Xu F, Lv YM, Wang HB, Song YC. miR-31-5p/SOX4 Axis Affects Autophagy and Apoptosis of Chondrocytes by Regulating Extracellular Regulated Protein Kinase/Mechanical Target of Rapamycin Kinase Signalling. Pathobiology 2021; 89:63-73. [PMID: 34753136 DOI: 10.1159/000519006] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 08/11/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Osteoarthritis (OA) is a common type of degenerative joint diseases that is regulated by a combination of complex intercellular signals and modulators, including non-coding RNAs. Mounting evidence suggests that miR-31-5p is physiologically involved in the regulation of chondrocytes, but the mechanism remains unclear. METHODS Expression levels of miR-31-5p and SOX4 in OA cartilage tissues and in IL-1β-stimulated chondrocytes were examined by quantification polymerase chain reaction (q-PCR) or immunohistochemistry assays. Cell proliferation and apoptosis were detected by Cell Counting Kit-8 (CCK-8) and flow cytometry assays, respectively. Expression of LC3 was detected using immunofluorescence staining. Expressions of autophagy-related proteins and extracellular regulated protein kinase (ERK)/mechanical target of rapamycin kinase (mTORC1) signal-related proteins were measured by Western blot analysis. Molecular interaction was validated by dual luciferase reporter assay. RESULTS Downregulation of miR-31-5p and upregulation of SOX4 were observed in both OA patients and OA chondrocytes. Mechanistic experiments revealed that miR-31-5p negatively modulated SOX4 expression by directly targeting its 3'- untranslated region. Moreover, overexpression of miR-31-5p suppressed the activation of mTORC1 in an ERK-dependent manner by inhibiting SOX4. Further functional experiments demonstrated that overexpressing miR-31-5p in OA chondrocytes markedly promoted its proliferation and autophagy while inhibiting apoptosis. However, these effects were abolished by overexpression of SOX4 or treatment with 3BDO, an mTOR activator. CONCLUSION These results demonstrated that miR-31-5p enhanced survival and autophagy of OA chondrocytes through inactivation of mTORC1 via directly targeting SOX4, suggesting that miR-31-5p may play a protective role in OA progression.
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Affiliation(s)
- Fei Xu
- Department of Orthopedics, Affiliated Hospital of Chengde Medical College, Chengde, China
| | - Yong-Ming Lv
- Department of Orthopedics, Affiliated Hospital of Chengde Medical College, Chengde, China
| | - Hai-Bin Wang
- Department of Orthopedics, Tangshan Central Hospital, Tangshan, China
| | - Ying-Chun Song
- Department of Anesthesiology, Affiliated Hospital of Chengde Medical College, Chengde, China
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8
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Jiménez-Uribe AP, Gómez-Sierra T, Aparicio-Trejo OE, Orozco-Ibarra M, Pedraza-Chaverri J. Backstage players of fibrosis: NOX4, mTOR, HDAC, and S1P; companions of TGF-β. Cell Signal 2021; 87:110123. [PMID: 34438016 DOI: 10.1016/j.cellsig.2021.110123] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/19/2021] [Accepted: 08/20/2021] [Indexed: 12/16/2022]
Abstract
The fibrotic process could be easily defined as a pathological excess of extracellular matrix deposition, leading to disruption of tissue architecture and eventually loss of function; however, this process involves a complex network of several signal transduction pathways. Virtually almost all organs could be affected by fibrosis, the most affected are the liver, lung, skin, kidney, heart, and eyes; in all of them, the transforming growth factor-beta (TGF-β) has a central role. The canonical and non-canonical signal pathways of TGF-β impact the fibrotic process at the cellular and molecular levels, inducing the epithelial-mesenchymal transition (EMT) and the induction of profibrotic gene expression with the consequent increase in proteins such as alpha-smooth actin (α-SMA), fibronectin, collagen, and other extracellular matrix proteins. Recently, it has been reported that some molecules that have not been typically associated with the fibrotic process, such as nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4), mammalian target of rapamycin (mTOR), histone deacetylases (HDAC), and sphingosine-1 phosphate (S1P); are critical in its development. In this review, we describe and discuss the role of these new players of fibrosis and the convergence with TGF-β signaling pathways, unveiling new insights into the panorama of fibrosis that could be useful for future therapeutic targets.
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Affiliation(s)
| | - Tania Gómez-Sierra
- Facultad de Química, Departamento de Biología, Universidad Nacional Autónoma de México, CDMX 04510, Mexico
| | - Omar Emiliano Aparicio-Trejo
- Departamento de Fisiopatología Cardio-Renal, Instituto Nacional de Cardiología "Ignacio Chávez", Mexico City 14080, Mexico
| | - Marisol Orozco-Ibarra
- Laboratorio de Neurobiología Molecular y Celular, Instituto Nacional de Neurología y Neurocirugía, Manuel Velasco Suárez, Av. Insurgentes Sur # 3877, La Fama, Alcaldía Tlalpan, CP 14269 Ciudad de México, Mexico
| | - José Pedraza-Chaverri
- Facultad de Química, Departamento de Biología, Universidad Nacional Autónoma de México, CDMX 04510, Mexico.
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9
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Lee SJ, Kim SJ, Jo DH, Park KS, Kim JH. Blockade of mTORC1-NOX signaling pathway inhibits TGF-β1-mediated senescence-like structural alterations of the retinal pigment epithelium. FASEB J 2021; 35:e21403. [PMID: 33559185 DOI: 10.1096/fj.202001939rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 01/04/2021] [Accepted: 01/15/2021] [Indexed: 11/11/2022]
Abstract
The retinal pigment epithelium (RPE) undergoes characteristic structural changes and epithelial-mesenchymal transition (EMT) during normal aging, which are exacerbated in age-related macular degeneration (AMD). Although the pathogenic mechanisms of aging and AMD remain unclear, transforming growth factor-β1 (TGF-β1) is known to induce oxidative stress, morphometric changes, and EMT as a senescence-promoting factor. In this study, we examined whether intravitreal injection of TGF-β1 into the mouse eye elicits senescence-like morphological alterations in the RPE and if this can be prevented by suppressing mammalian target of rapamycin complex 1 (mTORC1) or NADPH oxidase (NOX) signaling. We verified that intravitreal TGF-β1-induced stress fiber formation and EMT in RPE cells, along with age-associated morphometric changes, including increased variation in cell size and reduced cell density. In RPE cells, exogenous TGF-β1 increased endogenous expression of TGF-β1 and upregulated Smad3-ERK1/2-mTORC1 signaling, increasing reactive oxygen species (ROS) production and EMT. We demonstrated that inhibition of the mTORC1-NOX4 pathway by pretreatment with 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR), an activator of AMP-dependent protein kinase, or GKT137831, a NOX1/4 inhibitor, decreased ROS generation, prevented stress fiber formation, attenuated EMT, and improved the regularity of the RPE structure in vitro and in vivo. These results suggest that intravitreal TGF-β1 injection could be used as a screening model to investigate the aging-related structural and functional changes to the RPE. Furthermore, the regulation of TGF-β-mTORC1-NOX signaling could be a potential therapeutic target for reducing pathogenic alterations in aged RPE and AMD.
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Affiliation(s)
- Seok Jae Lee
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Soo-Jin Kim
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Dong Hyun Jo
- Department of Anatomy & Cell Biology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyu-Sang Park
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Jeong Hun Kim
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea.,Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea.,Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Republic of Korea.,Advanced Biomedical Research Center, Korea Research Institute of Bioscience & Biotechnology, Daejeon, Republic of Korea
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10
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Kim JJ, Wilbon SS, Fornoni A. Podocyte Lipotoxicity in CKD. KIDNEY360 2021; 2:755-762. [PMID: 35373048 PMCID: PMC8791311 DOI: 10.34067/kid.0006152020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 02/24/2021] [Indexed: 02/06/2023]
Abstract
CKD represents the ninth most common cause of death in the United States but, despite this large health burden, treatment options for affected patients remain limited. To remedy this, several relevant pathways have been identified that may lead to novel therapeutic options. Among them, altered renal lipid metabolism, first described in 1982, has been recognized as a common pathway in clinical and experimental CKD of both metabolic and nonmetabolic origin. This observation has led many researchers to investigate the cause of this renal parenchyma lipid accumulation and its downstream effect on renal structure and function. Among key cellular components of the kidney parenchyma, podocytes are terminally differentiated cells that cannot be easily replaced when lost. Clinical and experimental evidence supports a role of reduced podocyte number in the progression of CKD. Given the importance of the podocytes in the maintenance of the glomerular filtration barrier and the accumulation of TG and cholesterol-rich lipid droplets in the podocyte and glomerulus in kidney diseases that cause CKD, understanding the upstream cause and downstream consequences of lipid accumulation in podocytes may lead to novel therapeutic opportunities. In this review, we hope to consolidate our understanding of the causes and consequences of dysregulated renal lipid metabolism in CKD development and progression, with a major focus on podocytes.
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11
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Nguyen NT, Nguyen TT, Da Ly D, Xia JB, Qi XF, Lee IK, Cha SK, Park KS. Oxidative stress by Ca 2+ overload is critical for phosphate-induced vascular calcification. Am J Physiol Heart Circ Physiol 2020; 319:H1302-H1312. [PMID: 33095057 DOI: 10.1152/ajpheart.00305.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Hyperphosphatemia is the primary risk factor for vascular calcification, which is closely associated with cardiovascular morbidity and mortality. Recent evidence showed that oxidative stress by high inorganic phosphate (Pi) mediates calcific changes in vascular smooth muscle cells (VSMCs). However, intracellular signaling responsible for Pi-induced oxidative stress remains unclear. Here, we investigated molecular mechanisms of Pi-induced oxidative stress related with intracellular Ca2+ ([Ca2+]i) disturbance, which is critical for calcification of VSMCs. VSMCs isolated from rat thoracic aorta or A7r5 cells were incubated with high Pi-containing medium. Extracellular signal-regulated kinase (ERK) and mammalian target of rapamycin were activated by high Pi that was required for vascular calcification. High Pi upregulated expressions of type III sodium-phosphate cotransporters PiT-1 and -2 and stimulated their trafficking to the plasma membrane. Interestingly, high Pi increased [Ca2+]i exclusively dependent on extracellular Na+ and Ca2+ as well as PiT-1/2 abundance. Furthermore, high-Pi induced plasma membrane depolarization mediated by PiT-1/2. Pretreatment with verapamil, as a voltage-gated Ca2+ channel (VGCC) blocker, inhibited Pi-induced [Ca2+]i elevation, oxidative stress, ERK activation, and osteogenic differentiation. These protective effects were reiterated by extracellular Ca2+-free condition, intracellular Ca2+ chelation, or suppression of oxidative stress. Mitochondrial superoxide scavenger also effectively abrogated ERK activation and osteogenic differentiation of VSMCs by high Pi. Taking all these together, we suggest that high Pi activates depolarization-triggered Ca2+ influx via VGCC, and subsequent [Ca2+]i increase elicits oxidative stress and osteogenic differentiation. PiT-1/2 mediates Pi-induced [Ca2+]i overload and oxidative stress but in turn, PiT-1/2 is upregulated by consequences of these alterations.NEW & NOTEWORTHY The novel findings of this study are type III sodium-phosphate cotransporters PiT-1 and -2-dependent depolarization by high Pi, leading to Ca2+ entry via voltage-gated Ca2+ channels in vascular smooth muscle cells. Cytosolic Ca2+ increase and subsequent oxidative stress are indispensable for osteogenic differentiation and calcification. In addition, plasmalemmal abundance of PiT-1/2 relies on Ca2+ overload and oxidative stress, establishing a positive feedback loop. Identification of mechanistic components of a vicious cycle could provide novel therapeutic strategies against vascular calcification in hyperphosphatemic patients.
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Affiliation(s)
- Nhung Thi Nguyen
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.,Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Tuyet Thi Nguyen
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.,Internal Medicine Residency Program, College of Health Sciences, VinUniversity, Hanoi, Vietnam
| | - Dat Da Ly
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.,Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Jing-Bo Xia
- Key Laboratory of Regenerative Medicine, Ministry of Education, Department of Developmental and Regenerative Biology, Jinan University, Guangzhou, China
| | - Xu-Feng Qi
- Key Laboratory of Regenerative Medicine, Ministry of Education, Department of Developmental and Regenerative Biology, Jinan University, Guangzhou, China
| | - In-Kyu Lee
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Seung-Kuy Cha
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.,Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Korea
| | - Kyu-Sang Park
- Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.,Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Korea
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12
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Liu W, Li Y, Xiong X, Chen Y, Qiao L, Wang J, Su X, Chu F, Liu H. Traditional Chinese medicine protects against hypertensive kidney injury in Dahl salt-sensitive rats by targeting transforming growth factor-β signaling pathway. Biomed Pharmacother 2020; 131:110746. [PMID: 33152915 DOI: 10.1016/j.biopha.2020.110746] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/29/2020] [Accepted: 09/07/2020] [Indexed: 12/29/2022] Open
Abstract
This study investigated the therapeutic efficacy of Bu-Shen-Jiang-Ya decoction (BSJYD) on hypertensive renal damage to determine whether it regulates the expression of transforming growth factor-β (TGF-β)/SMADs signaling pathways, thereby relieving renal fibrosis in Dahl salt-sensitive (SS) rats. Dahl SS rats on a high-sodium diet were prospectively treated with BSJYD (n = 12) or valsartan (n = 12) for 8 weeks. The blood pressure (BP) of these rats was measured and their kidneys were subjected to biochemical analysis, including serum creatinine (Scr) and blood urea nitrogen (BUN); hematoxylin and eosin staining; Masson trichrome staining; real-time polymerase chain reaction; and western blot analysis. The primary outcome was that BSJYD significantly reduced BP, debased BUN, and Scr and ameliorated renal pathological changes. As underlying therapeutic mechanisms, BSJYD reduces TGFβ1 and Smad2/3 expression and suppresses renal fibrosis, as suggested by the decreased expression of connective tissue growth factor(CTGF). These data suggest that BSJYD acts as an optimal therapeutic agent for hypertensive renal damage by inhibiting the TGF-β/SMADs signaling pathway.
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Affiliation(s)
- Wei Liu
- Department of Cardiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Yixuan Li
- Community Healthcare Center of Shangzhuang Town, Haidian District, Beijing, 100053, China
| | - Xingjiang Xiong
- Department of Cardiology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Yuyi Chen
- Department of Oncology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Lumin Qiao
- Department of Emergency, Yinchuan Chinese Medicine Hospital, Ningxia, 750001, China
| | - Jie Wang
- Department of Cardiology, Guang'anmen Hospital, China Academy of Chinese Medical Sciences, Beijing, 100053, China
| | - Xing Su
- Medical Administration Division, Beijing Mentougou Hospital of Traditional Chinese Medicine, Beijing, 102300, China
| | - Fuyong Chu
- Department of Cardiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China.
| | - Hongxu Liu
- Department of Cardiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China.
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13
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Dou Y, Shang Y, Shen Y, Qu J, Liu C, Cao J. Baicalin alleviates adriamycin-induced focal segmental glomerulosclerosis and proteinuria by inhibiting the Notch1-Snail axis mediated podocyte EMT. Life Sci 2020; 257:118010. [DOI: 10.1016/j.lfs.2020.118010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2019] [Revised: 06/16/2020] [Accepted: 06/22/2020] [Indexed: 01/02/2023]
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14
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Kim SJ, Kim YS, Kim JH, Jang HY, Ly DD, Das R, Park KS. Activation of ERK1/2-mTORC1-NOX4 mediates TGF-β1-induced epithelial-mesenchymal transition and fibrosis in retinal pigment epithelial cells. Biochem Biophys Res Commun 2020; 529:747-752. [PMID: 32736702 DOI: 10.1016/j.bbrc.2020.06.034] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 06/07/2020] [Indexed: 11/19/2022]
Abstract
Transforming growth factor-β (TGF-β) plays a crucial role in the development of epithelial to mesenchymal transition (EMT) and fibrosis, particularly in an ocular disorder such as proliferative vitreoretinopathy (PVR). However, the key molecular mechanism underlying its pathogenesis remains unknown. In the present study, using cultured ARPE-19 cells, we determined that TGF-β initiates a signaling pathway through extracellular signal-regulated kinase (ERK)-mammalian target of rapamycin complex 1 (mTORC1) that stimulates trans-differentiation and fibrosis of retinal pigment epithelium. Blocking this pathway by a TGF-βRI, ERK or mTORC1 inhibitor protected cells from EMT and fibrotic protein expression. TGF-β1 treatment increased reactive oxygen species (ROS) via NOX4 upregulation, which acts downstream of ERK and mTORC1, as the ROS scavenger N-acetylcysteine and a pan-NADPH oxidase (NOX) inhibitor DPI dissipated excess ROS generation. TGF-β1-induced oxidative stress resulted in EMT and fibrotic changes, as NAC and DPI prevented α-SMA, Col4α3 expression and cell migration. All these inhibitors blocked the downstream pathway activation in addition to clearly preventing the activation of its upstream molecules, indicating the presence of a feedback loop system that may boost the upstream events. Furthermore, the FDA-approved drug trametinib (10 nM) blunted TGF-β1-induced mTORC1 activation and downstream pathogenic alterations through ERK1/2 inhibition, which opens a therapeutic avenue for the treatment of PVR in the future.
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Affiliation(s)
- Soo-Jin Kim
- Department of Physiology, Republic of Korea; Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | | | - Jeong Hun Kim
- Department of Ophthalmology & Biomedical Sciences, Seoul National University College of Medicine, South Korea; Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, South Korea
| | - Ha Young Jang
- Fight Against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, South Korea
| | - Dat Da Ly
- Department of Physiology, Republic of Korea; Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea
| | - Ranjan Das
- Department of Internal Medicine, Rush University Medical Center, Chicago, IL, USA.
| | - Kyu-Sang Park
- Department of Physiology, Republic of Korea; Mitohormesis Research Center, Yonsei University Wonju College of Medicine, Wonju, Republic of Korea.
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