C Igwe, O Ojiako, L Nwaogu, G Onyeze
antilipidemia, atherogenic index, lipid profile, phytochemicals
C Igwe, O Ojiako, L Nwaogu, G Onyeze. Lipid Lowering Effect Of Aqueous Leaf Extract Of Spondias Mombin Linn . The Internet Journal of Pharmacology. 2007 Volume 6 Number 1.
The effect of aqueous leaf extract of
In traditional medical practice of southern Nigeria, fresh boiled aqueous leaf extract of
Given the traditional, medicinal and domestic uses of
Materials And Methods
Collection, Identification and Extraction of Plant Materials
Apparently healthy fresh leaves of
Phytochemical analysis for the presence of alkaloids, tannins, saponins, flavonoids and cardiac and cyanogenic glycosides was carried out as described by Harborne (1973), and Trease and Evans (1983).
Experimental Animal Models
Forty-eight healthy female rabbits, 8-12 months old with mean weight 1.50 ± 0.52kg obtained locally from Owerri, Imo State, were randomly distributed into 4 groups (I-IV) of 12 rabbits each. They were housed separately and fed
Collection of Blood Samples
On the 0 th , and 2 hours after the second extract administration on the 4 th , 8 th and 12 th days, three animals were randomly selected from each group and 10ml of blood samples collected by cardiac puncture from each animal after mild anesthesia with chloroform in accordance with University Ethical Committee regulations. Serum was separated from the blood after clotting and centrifugation, and used for lipid analysis.
Serum total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and triacylglycerol (TG) were determined by enzymatic methods as described by Stein (1987), and Walmsley and White (1994). The concentration of free fatty acids (FFA) was estimated by standard titration method using 0.1N NaOH and phenolphthalein indicator (Nwanjo, 2004). The low-density lipoprotein cholesterol (LDL-C) was calculated using the Friedewald
Student's t-test and one-way analysis of variance (ANOVA) were used to compare the various data obtained. Values for p<0.05 were considered statistically significant.
Values are mean ± standard deviation. * Values are significant (p<0.05) compared to corresponding control values.
There was no significant (p>0.05) reduction in high-density lipoprotein cholesterol (HDL-C) in the treated animals in comparison with the control (Table 2). Similarly, variation in extract dose administration did not significantly (p>0.05) reduce HDL-C in the animals after 12 days of treatment with 250mg/kg and 500mg/kg of extract. On the other hand, treatment for 12 days with 750mg/kg of extract caused a slightly significant (p<0.05) reduction in HDL-C concentrations.
Triacylglycerol (TG) concentration of the animals administered with the extract was significantly (p<0.05) reduced in comparison with the control. This reduction was found to be significantly (p<0.05) extract-dose dependent (Table 3).
Extracts administration caused significant (p<0.05) decrease in loe-density lipoprotein cholesterol (LDL-C) concentration when it's concentrations in treated animals were compared with those of the control (Table 4). However, there was observed no significant (p>0.05) difference in the effects of varying extract dose administration on LDL-C concentration of treated animals.
Administration of extract at the different doses did not significantly (p>0.05) reduce atherogenic index of the treated animals in comparison with the controls (Table 5). Similarly, neither duration of treatment nor extract dose variation affected significantly (p>0.05) the atherogenic indexes of the animals.
Finally, administration of extract did not also cause significant (p>0.05) reductions in free fatty acid (FFA) levels (Table 6). Furthermore, the reductions were non-significantly (p>0.05) dose and duration dependent.
Secondary plant metabolites, such as saponins, alkaloids, phenols, flavonoids and tannins detected in
Results of the present study showed that aqueous leaf extract of
On the other hand, the extract even at the lowest dose used significantly reduced LDL-C concentration. Low-density lipoprotein transports cholesterol to the arteries where they can be retained by artierial proteoglycans, starting the formation of plaques. LDL-C poses a risk for cardiovascular disease when it invades the endothelium and become oxidized, since the oxidized form is more easily retained by the proteoglycans. Thus, increased levels of LDL-C are associated with artherosclerosis heart attack, stroke and peripheral vascular disease (Cromwell and Otvos, 2004).
The import of this LDL-C lowering effect of the extract is that the extract may aid in the prevention or reduction of cardiovascular risk factors. Cholesterol, triacylglycerol and fatty acids are significant and independent risk factors of adverse cardiovascular events (Wierbicki and Mikhailidis, 2002). The non-significant changes in the levels of atherogenic indexes of the extract treated animals may be due to the dependence of the index on the unvarying HDL-C. The non-significant reductions in the atherogenic indexes never-the-less, portend a decreased risk of vascular disease since high atherogenic index has been positively correlated with cardiovascular risk (Igwe
In conclusion, aqueous leaf extract of
The authors are grateful to the management of the Federal University of Technology, Owerri, Nigeria for partly sponsoring this research effort.