The relation between autophagy modulation by intermittent fasting and aquaporin 2 expression in experimentally induced diabetic nephropathy in albino rat

• Published in: Tissue & cell 2024-06, Vol.88, p.102395, Article 102395
• Main Authors: Hassan, Nora Hisham, Saleh, Dalia, Abo El-Khair, Salwa M., Almasry, Shaima M., Ibrahim, Amira
• Format: Article
• Language: English
• Subjects: Aquaporin 2; Autophagy; Diabetic nephropathy
• ISSN: 0040-8166; 1532-3072; 1532-3072
• DOI: 10.1016/j.tice.2024.102395

Polyuria is an early sign of diabetic nephropathy (DN) that produces dehydration in diabetic patients. This could be caused by alteration of renal aquaporin 2 (AQP2) expression. This study aimed to describe the relation between autophagy modulation via intermittent fasting (IF) and renal AQP2 expression and polyuria in case of DN. We divided the rats into control, DN and IF groups. After 2 and 4 weeks of diabetes induction, blood glucose (BG), serum creatinine (Scr), urine volume, and 24 hours urine protein (UP) were examined. Diabetic nephropathy histopathological index (DNHI) was calculated to evaluate histopathological changes. Immunohistochemistry and real-time PCR were performed to measure the levels of AQP2 and the autophagy marker; LC3 in kidney tissue. DNHI was correlated to the PCR and immunoexpression of AQP2 and LC3. Intermittent fasting significantly decreased the BG, Scr, urine volume, 24 hours UP, and DNHI as compared diabetes. Diabetes significantly elevated the immunoreactivity and mRNA expression levels of AQP2 and LC3 as compared to the control. However, the IF decreased AQP2 and stimulated autophagy in cyclic fashion. Our data revealed significant positive correlations between AQP2 and LC3 at the level of immunoexpression and mRNA at 2nd weeks. Taken together, these data showed that autophagy stimulation didn’t regulate AQP2 expression in case of diabetic nephropathy, however IF decreased polyuria through improvement of glycemic state. •Diabetes increased aquaporin 2 (AQP2) and LC3 mRNA and immunoexpression levels.•IF improved the diabetic state of the rats with diabetic nephropathy.•IF decreased renal AQP2 protein and stimulated the autophagy in a cyclical fashion.•There were significant positive correlations between AQP2 and LC3 protein and mRNA.•Autophagy stimulation doesn’t regulate AQP2 expression in diabetic nephropathy.