Hypoglycemic properties of Viscum album (mistletoe) in alloxan-induced diabetic animals

The aqueous leaf extract of Viscum album Stapf (Loranthaceae) given i.p. produced a dose-dependent fall in blood sugar. Doses of 200 mg/kg and 400 mg/kg body weight produced significant (p < 0.05) lowering of blood sugar in fasted normal white albino rats and alloxanized rabbits respectively. The fasting blood sugar, measured in milligram per 100 ml (mg%), in normoglycemic rats was reduced by 30.06% while in alloxanized rabbits, the blood sugar was reduced from mean value of 650 +/- 7.2 mg % at zero hour to 87 8.2 mg% at 4 h. The hypoglycemic effects were compared with those of tolbutamide. Acute toxicity studies of the extract in mice gave LD50 value of 4.18 +/- 0.96 g/kg body weight when given i.p. The mechanism underlying the observed hypoglycemic effect of V. album extract is not fully understood but may be related to enhancement in peripheral utilization of glucose and increase in insulin secretion.