Hypoglycaemic and hypolipidemic properties of the ethanolic and aqueous extracts,
respectively, from Chinese juniper (Juniperus chinensis L.) berries were investigated
in alloxan-induced diabetic rats.
After oral administration of each extract singly or repeatedly to alloxan-induced
diabetic rats, the blood glucose, glutamate-pyruvate transferase (GPT), glutamate-oxaloacetate
transaminase (GOT), total cholesterol (TC) and triglyceride (TG) levels were assayed.
The blood glucose levels after a single oral administration of the ethanolic extract
significantly reduced in a time-dependent manner, which is much faster and more than
that of glibenclamide. The blood glucose levels of alloxan-induced diabetic rats treated
with the ethanolic extract were reduced to 94, 81%, 66%, 45% and 40% at 1, 3, 5, 7
and 9h, respectively (p<0.05), while the aqueous extract had no effect at all. Repeated
oral administration of the ethanolic extract also effectively reduced the GPT value
to 58% of the diabetic rats, but slightly reduced the GOT value to 87% of the diabetic
rats (p<0.05). On the other hand, the repeated oral administration of aqueous extract
effectively reduced the GOT value to 43% of the diabetic rats, without affecting the
GPT level. Effects of both extracts on the TC and TG levels were different. There
was no significant difference in the TC and TG levels between diabetic control and
diabetic groups when repeatedly administered orally with ethanolic extract. On the
other hand, the aqueous extract brought down the TC value to 57% and the TG value
to 37% of the diabetic control rats (p<0.05).
The results suggested that the ethanolic extract of Chinese juniper berries possesses
a potential hypoglycaemic effect while the aqueous extract has a potential hypolipidemic
effect.