Potential Anti-Diabetic Activity of Pueraria lobata Flower (Flos Puerariae) Extracts

<i>Pueraria lobata</i> (Wild.) Ohwi. (<i>P. lobata</i>) flowers known as 'Kudzu flower' contain isoflavonoids and essential oil components. They have a wide range of biological and pharmacological activities, including protective effects against non-alcoholic fatty liver disease, hyperglycemia, and hypolipidemia, anti-mutagenic effects, and benefits for weight loss. However, the molecular mechanism of these effects remains unclear. Our study aimed to systematically examine the effects of flos puerariae crude extract (FPE) as an anti-diabetic agent using in vitro assays. The cytotoxicity of FPE was evaluated using MTS assay in L6 rat myocyte and 3T3-L1 murine fibroblast cell lines. PPARγ binding activity and adipogenesis were examined using dual-luciferase and differentiation assays, respectively. For investigating the anti-diabetic activity, glucose utilization, including GLUT4 protein expression, glucose uptake assay, and GLUT4 translocation using immunofluorescence microscopy were conducted in L6 cells. Furthermore, we assessed the antioxidant and anti-inflammatory activities of FPE. Our results demonstrated the ability to augment glucose uptake in L6 cells and enhance glucose utilization activity by increasing the expression of glucose transporter type 4 (GLUT4). In summary, our findings suggest that FPE may be a potential anti-diabetic substance for the treatment of diabetic patients and can prevent inflammatory or oxidation-related diseases.