Glucose transport activity on adipocytes by extracts form Thai medicinal plants used to treat diabetic patients

Ten Thai medicinal plants which have been used by Thai folk doctors for treatment of diabetic patients were selected for test hypoglycemic activity by promoting the glucose transport in adipocyte cells. The uptake of radioactive 2-deoxyglucose in 3T3-L1 adipocytes was evaluated in this assay [1]. The antioxidant activity by DPPH assay was also investigated [2]. The extraction method of all plants in analogy to the method of folk doctors was the maceration in 95% ethanol. The results showed that Nelumbo nucifera and Tacca chantrieri showed the highest values for increase of glucose uptake in adipocytes at 0.1µg/ml (1.7and 1.6 fold of basal) and also have good antioxidant activity (EC50=5.33 and 10.24µg/ml). Piper sarmentosum also showed the highest hypoglycemic activity in the glucose uptake assay at 1.0µg/ml (1.7 fold of basal) but its extract exhibited less antioxidant activity (EC50=83.18µg/ml). The study found that all plant extracts showed high glucose uptake to adipocyte cells but the low dose of all extracts exhibited more effective glucose uptake than the high dose. In addition, most plant extracts (7 in 10 plants) also showed relation between hypoglycemic and antioxidant activity. In conclusion, these results should support the use of Thai folk doctors for treatment of diabetic patients.

Acknowledgements: Faculty of Medicine, Thammasart University for financial support

References: 1. Hong SJ et al (2000)J Med Sci;16:445–51.

2. Yamazaki K, et al (1994) Chem Pharm Bull; 42:1663–5.