Study on antidiabetic constituents of Tibetan Medicine Meiduoluomi / 中草药

ABSTRACT

Objective: To study the antidiabetic constituents of Tibetan Medicine "Meiduoluomi". Methods: Erigeron multiradiatus (EM) is one of the crude materials. The chemical constituents in EM were extracted and isolated by extraction and macroporous resin column. The inhibitory activities of the extracts against aldose reductase (AR) were evaluated in vitro to make sure the active fragments. Diabetic rats induced by streptozotocin were randomly divided into four groups model (distilled water), positive control (epalrestat 10 mg/kg), EM II low-and high-dosage (200, 400 mg/kg) groups. The rats were ig administered once daily for 11 weeks. The rat normal sign, body weight, urine glucose, blood glucose, hemodynamics, and cardiac function parameters were determined. Results: Both EM I and EM II showed the inhibitory activities against AR with IC50 values of 0.64 and 0.12 mg/mL, respectively. Compared with diabetic group, body weight, heart rate, left ventricular end diastolic pressure average (LEVDP) and the left ventricular maximum rate of pressure development (+dp/dtmax) in EM II group were significantly improved, while blood glucose was decreased (P < 0.05, 0.01, 0.001). Conclusion: EM II demonstrates the obvious inhibitory activity on AR, and could improve the hemodynamics and protect heart function, which may be the antidiabetic active constituents of "Meiduoluomi".