Conclusion
Our results support the hypothesis that gallic acid might serve as a potential supplement to metformin to enhance the therapeutical effect of metformin.
Methods
Streptozotocin (65 mg/kg) intraperitoneal injection was used to induce diabetic kidney disease in mice. The diabetic mice were treated with saline (Vehicle), gallic acid (GA) (30 mg/kg), metformin (MET) (200 mg/kg), or the combination of gallic acid (30 mg/kg) and metformin (200 mg/kg) (GA + MET).
Results
Our results demonstrated that compared to the untreated diabetic mice, all three strategies (GA, MET, and GA + MET) exhibited various effects on improving renal morphology and functions, reducing oxidative stress in kidney tissues, and restoring AMP-activated protein kinase (AMPK)/silent mating type information regulation 2 homolog 1 (SIRT1) signaling in kidney tissues of diabetic mice. Notably, the combination strategy (GA + MET) provided the most potent renal protection effects than any single strategies (GA or MET).