Comparative Hypolipidaemic Effect of Aqueous Extract of Psidium guajava Leaves and Ascorbic Acid in Male Rats

Abstract

Aim: To assess the hypolipidaemic properties of aqueous extract of Psidium guajava leaves (AEPGL) and ascorbic acid (vitC) in male albino Wistar rats. Study Design: Three groups of rats were respectively administered distilled water, 200mg/kg of AEPGL and vitC orally, for thirty days, to determine the hypolipidaemic properties of AEPGL and vitC. The hypolipidaemic properties were determined from the serum lipid profile of the rats. Place and Duration of Study: This work was carried out in Biochemistry Department, University of Calabar, Calabar, Nigeria between January and February, 2012.  Methodology: Eighteen albino Wistar rats, divided in three groups of six rats each, were used in this study. The rats in group I (control) were administered, by oral gavage, with 2ml of distilled water. While the rats in groups II and III received 200/mg/kg body weight oral daily doses of aqueous extract of AEPGL and vitC, respectively, using orogastric tubes for 30 days. The hypolipidaemic properties of AEPGL and vitC were determined from their effect on serum lipid profile of the treated rats, using serum total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), high density lipoprotein cholesterol (HDL-C), TG/HDL-C and artherogenic index of plasma (AIP). Standard reagent kits were used to determine serum TC, TG and HDL-C, while LDL-C, VLDL-C, TG/HDL-C and AIP were calculated. Result: The results showed that serum HDL-C level obtained for rats treated with AEPGL (7.10 ± 0.11mg/dl) and vitC (6.93 ± 0.11mg/dl) were significantly (p<0.05) increased, compared respectively to that of the control rats (3.73 ± 0.18mg/dl). While the levels of TC, TG, LDL-C, VLDL-C, TG/HDL-C and AIP obtained rats treated with AEPGL (4.63 ± 0.21, 3.45 ± 0.14, -3.15 ± 0.28, 0.68 ± 0.02mg/dl, 0.48 ± 0.02 and -0.32 ± 0.02, respectively ) and vitC (4.68 ± 0.18, 3.65 ± 0.15, -2.98 ± 0.24, 0.73 ± 0.03 mg/dl, 0.53 ± 0.03 and -0.28 ± 0.03, respectively) were significantly (p<0.05) decreased, compared respectively to the control rats (7.22 ± 0.06, 6.87 ± 0.10, 2.12 ± 0.21, 1.37 ± 0.02mg/dl, 1.88 ± 0.08 and 0.27 ± 0.02, respectively). However, the percentage increase in serum HDL-C, and decrease in serum TC, TG, (LDL-C), VLDL-C, TG/HDL-C and AIP associated with administration of AEPGL was observed to be insignificantly (p>0.05) higher than that recorded for vitamin C. Conclusion: In conclusion, the results of this study indicate that AEPGL and vitC possess hypolipidaemic, hence antiatherogenic, properties in male rats, thereby supporting the local use of P. guajava leaves in the management of hypertensive conditions.