A Study of the Effect of Phyllanthus Amarus Extracts on Blood Glucose in Rabbits

Abstract

Aerial parts of Phyllanthus amarus are used by Traditional Healers of Tanga, northeastern Tanzania, to control symptoms of non-insulin dependent diabetes mellitus (NIDDM). An aqueous extract of the aerial parts, 0.1 and 1 g/kg body weight, significantly enhanced clearance of glucose from the blood as compared to controls during an oral glucose tolerance test (OGTT), using normal fasted albino rabbits (P ≤ 0.05). The two doses of the extract reduced the area under the OGTT curve by 7.8% and 11.4%, respectively. Both doses had no effect on blood glucose in the unfed rabbits. Chlorpropamide, 0.1 g/kg body weight, showed a greater effect, than both doses, on glucose clearance in the fed state and on blood glucose in the fasted rabbits (P ≤ 0.05). A methanol extract of the aerial parts, 1 g/kg body weight, worsened glucose tolerance causing a significant increase in area under the OGTT and fasting blood glucose curves (P ≤ 0.05). We conclude that the aqueous extract contains a hypoglycaemic activity as claimed by traditional healers. This activity is absent in the methanol extract, thus emphasizing the importance of preparing extracts in the same way as the healers. Further work is required to isolate the active substance before proper comparison with a standard drug can be done.

α-Amylase inhibitory activity of some Malaysian plants used to treat diabetes; with particular reference to Phyllanthus amarus

“…From this study, it was clear that the second method (pre-incubation method) gave a better inhibitory effect compared to the first (without preincubation). This study suggested that the plant has a very strong inhibition on ␣-amylase which may contribute to its demonstrated in vivo anti diabetic effect (Srividya and Periwal, 1995;Moshi et al, 1997;Raphael et al, 2002). It was decided to use the pre-incubation method for bioassay-guided fractionation and isolation of compounds from the extract.…”

The effect of Phyllanthus amarus aqueous extract on blood glucose in non‐insulin dependent diabetic patients

“…The dose was deliberately chosen to be within the range used in rabbits because it was being administered repeatedly. Based on the results from the previous work on rabbits (Moshi et al, 1997) it is tempting to suggest that the response could have been better if a bigger dose of the extract was used. This could also account for the observed.…”

“…The results from this study show no evidence of a hypoglycaemic effect on NIDDM patients. In a previous work, on normal fasted albino rabbits (Moshi et al, 1997), it was shown that 0.1 and 1 g/kg body weight of an aqueous extract of the plant caused a dose-dependent increase in the clearance of an administered oral glucose load from the blood. However, the extract did not significantly lower FBG.…”

“…An aqueous extract of P. amarus at a dose of 0.1 and 1.0 g/kg body weight, enhanced the clearance of an oral glucose load from the blood of normal white albino rabbits but did not significantly lower FBG (Moshi et al, 1997). Since there are no reports in literature of the clinical use of extracts of this plant in diabetes, this work was done as an attempt to substantiate its traditional uses using NIDDM patients.…”

Phyllanthus amarus: Ethnomedicinal uses, phytochemistry and pharmacology: A review

“…Both doses had no effect on blood glucose in the unfed rabbits. A methanolic extract of the aerial parts, 1 g/kg body weight, worsened glucose tolerance causing a significant increase in area under the OGTT and fasting blood glucose curves (Moshi et al, 1997).…”