Related Experiment Video
Updated: Jul 11, 2026

Modeling and Evaluation of Murine Diabetic Cardiomyopathy Model
Published on: November 29, 2024
Thiazolidinediones provide better renoprotection than insulin in an obese, hypertensive type II diabetic rat model
S Ohtomo1, Y Izuhara, S Takizawa
1Institute of Medical Sciences, Tokai University, Kanagawa, Japan.
Abstract:
Hyperinsulinemia has been implicated in the development of diabetic nephropathy. In the present study we compared the renoprotective effects of the thiazolidinedione, pioglitazone (PGZ), to that of insulin in a hypertensive, obese, type II diabetic rat model. PGZ aggravated obesity and gave less glycemic control than insulin. However, renoprotection was markedly better with PZG compared to insulin as shown by lower proteinuria, improved renal function, and less histological evidence of diabetic glomerular and tubulointerstitial lesions. PZG and insulin both reduced renal accumulation of pentosidine and oxidative stress to a similar extent. In contrast, PGZ but not insulin suppressed enhanced transforming growth factor-beta (TGF-beta) expression. We further confirmed in cultured rat proximal tubular cells that insulin enhanced TGF-beta mRNA expression and protein production. Our results identify hyperinsulinemia and the attendant increase of TGF-beta expression as potential therapeutic targets in diabetes independent of glycemic control. This confirms prior clinical evidence that PZG provides renoprotection in obese, diabetic patients with nephropathy.
Related Concept Videos
Oral Hypoglycemic Agents: Biguanides and Glitazones
Antihypertensive Drugs: Thiazide-Class Diuretics
Dipeptidyl Peptidase 4 Inhibitors
Glucagon-like Receptor Agonists
GLP-1, when administered in high doses intravenously, triggers insulin secretion, inhibits glucagon release, slows gastric emptying, reduces food intake, and restores normal insulin secretion. However, its rapid inactivation by the...
Type II Diabetes II: Pathophysiology
Oral Hypoglycemic Agents: Sulfonylureas