Effects of Cysteine-Stabilised Peptide Fraction of Aqueous Extract of Morinda lucida Leaf on Selected Cardiovascular Disease Indices in Mice.

Abstract

This study evaluated the effects of cysteine-stabilised peptide fraction (CSPF) of aqueous extract of Morinda lucida leaf on selected cardiovascular disease indices in mice. Sixty adult Swiss Albino mice were randomly divided into 6 groups (n = 10). Group A served as control and received 5% DMSO. Half of the mice in groups B, C, D, E and F received 31.25, 62.5, 125, 250, and 500mg/kg body weight of CSPF respectively for 7days while the other half received the various doses for 28days. After the experimental period, selected cardiovascular disease indices were determined in the mice. The results revealed that CSPF significantly reduced (p < 0.05) atherogenic index, plasma concentrations of total cholesterol and LDL-cholesterol but significantly increased (p < 0.05) plasma HDL-cholesterol concentration at higher doses after 28days of administration. Plasma lactate dehydrogenase, aspartate aminotransferase and alkaline phosphatase activities were not significantly altered (p > 0.05) at all doses of the CSPF after 7 and 28days of administration compared to controls. After 7days of CSPF administration, the activities of heart Ca2+, Mg2+-ATPase and Na+-K+-ATPase were not significantly altered (p > 0.05) but heart Mg2+-ATPase activity was significantly increased (p < 0.05) at 250mg/kg body weight compared to controls. Also, 28days of CSPF administration at all doses had no significant effect (p > 0.05) on the activities of heart Mg2+-ATPase and Na+-K+-ATPase of mice compared to controls but heart Ca2+-Mg2+-ATPase activity was significantly increased (p < 0.05) at the highest dose with no significant alteration (p > 0.05) at other doses compared to controls. Generally, CSPF administration had no significant effect (p > 0.05) on haematological parameters after 7 and 28days. These results suggest that CSPF may not predispose subjects to cardiovascular diseases.