WHO monographs on selected medicinal plants - travolekar.ru

Fructus Momordicae
Alcohol- and aqueous extracts of the fruit pulp (1:1) (50.0, 100.0 and
200.0 mg/kg bw per day) were evaluated in a pilot study (plasma glucose
> 180 mg/dl, 21 days), a chronic study in alloxanized rats (plasma glucose
> 280.0 mg/dl, 120 days) and streptozotocin-treated mice (plasma glucose
> 400.0 mg/dl, 60 days). The maximum antihyperglycaemic effect occurred
with an aqueous extract at week 3, at a dose of 200.0 mg/kg bw per
day. In chronic alloxanized rats, treatment with the aqueous extract led to
a reduction of 64.33%, 66.96%, 69.7% and 70.53% in plasma glucose
levels after 1, 2, 3 and 4 months of treatment, respectively. In mice with
chronic streptozotocin-induced diabetes, treatment with the aqueous extract
led to a mean reduction of 15.37%, 18.68% and 22.86% in plasma
glucose levels on days 40, 50 and 60, respectively (34).
Another similar study that examined the hypoglycaemic potency of
the crude drug in rats with streptozotocin-induced diabetes found no effect
(35). In this investigation the animals were maintained on a semisynthetic
diet containing 0.5% freeze-dried bitter gourd powder for
6 weeks. The excretion of glucose, protein, urea and creatinine was monitored
throughout the experiment. Plasma glucose, albumin, urea and cholesterol
were analysed at the end of the experiment. No beneficial effects
were observed (35).
The anti-hyperglycaemic effects of three extracts of the crude drug
were assessed in rats. Three different aqueous extracts of powdered fresh
or dried whole fruits were prepared and orally administered to rats with
streptozotocin-induced diabetes. An aqueous extract of the powdered
fresh unripe whole fruits was the most active, and, at a dose of 20.0 mg/kg
bw, reduced fasting blood glucose by 48%, an effect comparable to that of
glibenclamide. The aqueous extract was tested for nephrotoxicity, hepatotoxicity
and elevation of liver enzymes and showed no signs of nephrotoxicity
or hepatotoxicity (36).
The antidiabetic activity of an aqueous extract of the fruit was assessed
in KK-Ay mice with type 2 diabetes with hyperinsulinaemia. The extract
reduced the blood glucose of KK-Ay mice 3 weeks after oral administration
(p < 0.01) and also significantly lowered the serum insulin of KK-Ay
mice under similar conditions (p < 0.01). However, the extract did not affect
the blood glucose in normal mice. In KK-Ay mice treated with the
extract, blood glucose was significantly decreased in an insulin tolerance
test. Moreover, the muscle content of facilitative glucose transporter isoform
4 (GLUT4) protein in the plasma membrane fraction of muscle significantly
increased in the mice that received the extract orally when compared
with that of the controls (p < 0.01) (37). In a follow-up study, the
antidiabetic activity of the extract combined with exercise was investi-
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