Differential expression of endoplasmic reticulum stress-response proteins in different renal tubule subtypes of OVE26 diabetic mice.

Differential expression of endoplasmic reticulum stress-response proteins in different renal tubule subtypes of OVE26 diabetic mice. Cell Stress Chaperones. 2015 Oct 20; Authors: Barati MT, Powell DW, Kechavarzi BD, Isaacs SM, Zheng S, Epstein PN, Cai L, Coventry S, Rane MJ, Klein JB Abstract Regulation of the endoplasmic reticulum (ER) stress-response pathway during the course of diabetes specifically in renal tubules is unclear. Since tubule cell dysfunction is critical to progression of diabetic nephropathy, this study analyzed markers of ER stress response and ER chaperones at different stages of diabetes and in different renal tubule subtypes of OVE26 type-1 diabetic mice. ER stress-response-induced chaperones GRP78, GRP94, and protein disulfide isomerase (PDI) were increased in isolated cortical tubules of older diabetic mice, while PDI was decreased in tubules of young diabetic mice. Immunofluorescence staining of kidneys from older mice showed GRP78 and PDI upregulation in all cortical tubule segments, with substantial induction of PDI in distal tubules. Protein kinase RNA-like endoplasmic reticulum kinase (PERK) phosphorylation was increased in cortical tubules of young diabetic mice, with no differences between older diabetic and control mice. Expression of ER stress-induced PERK inhibitor p58(IPK) was decreased and then increased in all tubule subtypes of young and older mice, respectively. Knockdown of PERK by small inter...
Source: Cell Stress and Chaperones - Category: Cytology Authors: Tags: Cell Stress Chaperones Source Type: research