INHIBITION OF LIPID ACCUMULATION IN 3T3-L1 ADIPOCYTES BY MORINDA CITRIFOLIA LINN. LEAF EXTRACTS AND COMMERCIAL HERBAL FORMULAS FOR WEIGHT CONTROL

Objective: To determine the in vitro anti-obesity effects of Morinda citrifolia leaf extract and herbal formulas used for weight loss in Thailand on lipid accumulation in 3T3-L1 adipocytes. Methods: Differentiated 3T3-L1 adipocytes were treated with 0.1, 0.5 and 1 mg/ml M. citrifolia leaf extract, three herbal formulas (JL-RU, JL-TH, CD-H) and 1, 5 and 10 mg/ml rutin, gallic acid and caffeine. Lipid accumulation determined by measuring Oil Red O staining and triglyceride content measured by a colorimetric method in adipocytes were assayed compared to the control. The effect of test samples on the viability of preadipocytes and differentiated adipocytes were investigated.Results: Differentiated adipocytes treated with 1 mg/ml M. citrifolia extract moderately inhibited fat accumulation (45.12%) and highly reduced triglyceride content (85.09%). Among the three herbal formulas, JL-TH considerably inhibited fat accumulation (109.17%, 1 mg/ml) and decreased triglyceride content (95.00%, 1 mg/ml) in adipocytes; this was higher than that for CD-H and JL-RU, respectively. The viability of preadipocytes treated with CD-H at 1 mg/ml was slightly decreased while those treated with JL-TH at 0.05-1 mg/ml showed moderately decreased viability in a dose-response manner. For differentiated adipocytes, CD-H at 0.5-1 mg/ml moderately decreased cell viability while JL-TH at 0.05-1 mg/ml caused moderate to high reduction of cell viability in a dose-response relationship. Conclusion: M. citrifolia extract and three herbal formulas had anti-obesity effects in 3T3-L1 adipocytes, as indicated by a significant reduction in lipid accumulation, triglyceride content, and cell viability. These findings suggest a potential therapeutic approach for the prevention and treatment of obesity.