Effects of Tangduqing Granules on Insulin Resistance and Their Association with AhR and PPARs Regulation in Type 2 Diabetic Rats Exposed to Persistent Organic Pollutants

Abstract

Objectives Tang Du Qing granules, a traditional Chinese medicine for diabetes, may alleviate insulin resistance induced by persistent organic pollutant exposure. This study aims to explore the mechanism by which Tang Du Qing granules improve insulin resistance in rats exposed to PCB126. Methods Male ZDF (fa/fa) rats were divided into a PCB126-exposed group and a model control group. Male ZDF (fa/+) rats served as the normal control group. Normal controls received a regular diet with olive oil via gavage, while the model control group received special feed with olive oil. PCB126 group received special feed with PCB126 in olive oil for 8 weeks. Post-exposure, the positive drug treatment group received CH223191, and Tang Du Qing granules were administered at high, medium, and low doses for 4 weeks. Relevant biochemical indicators and molecular signaling changes were assessed. Results PCB126 exposure increased levels of FBG, FINS, HOMA-IR and elevated serum TG, TC, and FFA in ZDF (fa/fa) rats compared to the model control group ( P < .05). The Tang Du Qing-treated group showed decreased FBG, FINS, HOMA-IR levels, and reduced serum TC, TG, and FFA compared to PCB126-exposed control group ( P < .05). Additionally, the Tang Du Qing-treated group downregulated hepatic AhR, CD36, and TNFα expression, while upregulating PPARα, PPARγ, GLUT4, and FGF21 expression ( P < .05). Conclusion Tang Du Qing granules ameliorate glucose and lipid toxicity and insulin resistance induced by PCB126 exposure in ZDF (fa/fa) rats by modulating the imbalance between AhR and PPARs and related molecular signals.