Influence of Dietary Chitosan Feeding Duration on Glucose and Lipid Metabolism in a Diabetic Rat Model.

Shing-Hwa Liu,Meng-Tsan Chiang,Chen-Yuan Chiu,Shih-An Feng

doi:10.3390/molecules26165033

Abstract

This study was designed to investigate the influence of dietary chitosan feeding-duration on glucose and lipid metabolism in diabetic rats induced by streptozotocin and nicotinamide [a non-insulin-dependent diabetes mellitus (NIDDM) model]. Male Sprague-Dawley rats were used as experimental animals and divided into short-term (6 weeks) and long-term (11 weeks) feeding durations, and each duration contained five groups: (1) control, (2) control + 5% chitosan, (3) diabetes, (4) diabetes + 0.8 mg/kg rosiglitazone (a positive control), and (5) diabetes + 5% chitosan. Whether the chitosan feeding was for 6 or 11 weeks, the chitosan supplementation decreased blood glucose and lipids levels and liver lipid accumulation. However, chitosan supplementation decreased plasma tumor necrosis factor (TNF)-α, insulin levels, alanine aminotransferase (ALT) activity, insulin resistance (HOMA-IR), and adipose tissue lipoprotein lipase activity. Meanwhile, it increased plasma high-density lipoproteins (HDL)-cholesterol level, plasma angiopoietin-like-4 protein expression, and plasma triglyceride levels (at 11-week feeding duration only). Taken together, 11-week (long-term) chitosan feeding may help to ameliorate the glucose and lipid metabolism in a NIDDM diabetic rat model.

Highlights

Diabetes mellitus (DM) is a global chronic metabolic disease
After both 6 and 11 weeks of being fed different diets, there were no significant differences in body weight, food intake, and feed efficiency among the groups [control (C), 5% high molecular weight (MW) chitosan (CS), diabetes (DM), DM + thiazolidinediones (TZD-rosiglitazone; a positive control), and DM + CS; Table 1]
We found that chitosan supplementation at both 6- and 11-week feeding durations could improve the accumulation of lipids in the livers of diabetic rats by increasing the protein expression of liver microsomal triglyceride transfer proteins (MTTP) and inhibit intestinal lipid digestion and absorption capacity by increasing the intestinal angiopoietin-like protein-4 (Angptl4) protein expression and by decreasing the intestinal MTTP protein expression

Summary

Introduction

Diabetes mellitus (DM) is a global chronic metabolic disease. More than 90% of diabetic patients suffer from type 2 DM (non-insulin-dependent DM; NIDDM) [1]. Dietary fibers are suggested to have beneficial effects on the plasma lipids of patients with diabetes and atherosclerosis. Guo et al (2020) have reported that the blood glucose level of patients with diabetes and obesity/overweight can be improved by supplementation with chitosan for at least 13 weeks [12]. Our previous study revealed that 7-week chitosan feeding did not affect blood glucose level but did decrease HOMA-IR index [13]. These findings indicate that the effects of chitosan on blood glucose and cholesterol concentrations in type 2 diabetes still remain to be clarified. The effectiveness of chitosan on glucose and lipid metabolism for long-term or short-term use is still inconclusive

Methods

Results

Discussion

Conclusion