| Resume |
We investigated the antidiabetic effect of
Moringa olifeira Lam. in a diet-induced obesity (DIO)
mouse model. Six mice were randomly selected as
normal controls. Moringa olifeira Lam. leaf extract
at a dose of 200, 400 or 600 mg/kg body weight, glibenclamide
(Glib) at the dose of 10 mg/kg (positive
control) and distilled water at 10 ml/kg (control
group) were administered orally by gastric intubation,
and each group consisted of six mice. Insulinsensitive
tissues (liver, skeletal muscle) were collected
to investigate antidiabetic effects and examine the
plant’s molecular mechanisms. Moringa olifeira Lam.
leaf extract prevented weight gain. It also reduced
blood glucose in DIO mice. Glib and Moringa olifeira
Lam. leaf extract, 400 mg/kg, treatments restored insulin
levels towards normal values (P < 0.05 versus
diabetic control group). Western immunoblot analysis
of different tissues, collected at the end of the
study, demonstrated that Moringa olifeira Lam. stimulated
activation of the insulin-dependent Akt
pathway and increased the protein content of Glut 4 in skeletal muscle. The improvement of hepatic steatosis
observed in DIO-treated mice was associated
with a decrease in the hepatic content of SREBP-1, a
transcription factor involved in de novo lipogenesis.
The hepatic PPARα protein content in the plant extract-
treated mice remained significantly higher
than those of the control group (P < 0.05). In conclusion,
this study provides the first evidence for direct
action of Moringa olifeira Lam. on pancreatic β-cells,
enhancing glucose-stimulated insulin secretion. This
correlated with hypoglycaemic effects in diabetic
mice associated with restored levels of plasma insulin. |