Your browser doesn't support javascript.
loading
Intrarenal renin-angiotensin system mediates fatty acid-induced ER stress in the kidney.
Li, Chunling; Lin, Yu; Luo, Renfei; Chen, Shaoming; Wang, Feifei; Zheng, Peili; Levi, Moshe; Yang, Tianxin; Wang, Weidong.
Afiliação
  • Li C; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China;
  • Lin Y; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China;
  • Luo R; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China;
  • Chen S; Department of Orthopedics, The 5th Affiliated Hospital, Sun Yat-sen University, Zhuhai, China;
  • Wang F; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; wangwd6@mail.sysu.edu.cn.
  • Zheng P; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China;
  • Levi M; Department of Medicine, Division of Hypertension and Renal Diseases, University of Colorado Denver, Aurora, Colorado; and.
  • Yang T; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China; Department of Medicine, Division of Renal Diseases and Hypertension, University of Utah, Salt Lake City, Utah.
  • Wang W; Institute of Hypertension, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China;
Am J Physiol Renal Physiol ; 310(5): F351-63, 2016 Mar 01.
Article em En | MEDLINE | ID: mdl-26672616
Obesity-related kidney disease is related to caloric excess promoting deleterious cellular responses. Accumulation of saturated free fatty acids in tubular cells produces lipotoxicity involving significant cellular dysfunction and injury. The objectives of this study were to elucidate the role of renin-angiotensin system (RAS) activation in saturated fatty acid-induced endoplasmic reticulum (ER) stress in cultured human proximal tubule epithelial cells (HK2) and in mice fed with a high-fat diet. Treatment with saturated fatty acid palmitic acid (PA; 0.8 mM) for 24 h induced ER stress in HK2, leading to an unfolded protein response as reflected by increased expressions of the ER chaperone binding immunoglobulin protein (BiP) and proapoptotic transcription factor C/EBP homologous protein (CHOP) protein as evaluated by immunoblotting. PA treatment also induced increased protein expression of inositol requiring protein 1α (IRE1α), phosphorylated eukaryotic initiation factor-α (eIF2α), and activating transcription factor 4 (ATF4) as well as activation of caspase-3. PA treatment was associated with increased angiotensin II levels in cultured medium. The angiotensin II type 1 receptor (AT1R) blocker valsartan or renin inhibitor aliskiren dramatically suppressed PA-induced upregulation of BiP, CHOP, IRE1α, p-eIF2α, and ATF4 in HK2 cells. In contrast, valsartan or aliskiren did not prevent ER stress induced by tunicamycin. C57BL/6 mice fed with a high-fat diet for 14 wk exhibited increased protein expressions of BiP and CHOP compared with control mice, which were significantly attenuated by the valsartan treatment. Increased angiotensin II levels in serum and urine were observed in mice fed with a high-fat diet when compared with controls. It is suggested that the intrarenal RAS activation may play an important role in diabetic kidney injury via mediating ER stress induced by saturated fatty acid.
Assuntos
Palavras-chave

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Sistema Renina-Angiotensina / Ácido Palmítico / Estresse do Retículo Endoplasmático / Dieta Hiperlipídica / Nefropatias / Túbulos Renais Proximais Tipo de estudo: Prognostic_studies Limite: Animals / Humans / Male Idioma: En Ano de publicação: 2016 Tipo de documento: Article

Texto completo: 1 Base de dados: MEDLINE Assunto principal: Sistema Renina-Angiotensina / Ácido Palmítico / Estresse do Retículo Endoplasmático / Dieta Hiperlipídica / Nefropatias / Túbulos Renais Proximais Tipo de estudo: Prognostic_studies Limite: Animals / Humans / Male Idioma: En Ano de publicação: 2016 Tipo de documento: Article