PENGARUH PEMBERIAN FOLAT TERHADAP KADAR HOMOSISTEIN SERUM DAN MALONDIALDEHID PLASMA STUDI EKSPERIMENTAL PADA TIKUS SPRAGUE DAWLEY YANG DIINDUKSI STREPTOZOTOCIN

Abstract

Background: Diabetes mellitus (DM) associated with increased level and oxidative activity of homocystein (Hcy) that cause oxidative stress. Plasma malondialdehyde (MDA) known as a marker of oxidative stress. Folate is required to decrease Hcy level. Folate acting as methyl donor in metabolism of Hcy to be metionin,and prevent oxidative stress. Objective: to demonstrate the effect of 30-days gradual dose folate supplementation on the decrease of plasma Hcy and MDA levels in SD rats induced by STZ. Method: an experimental study with a randomized controlled group pretest postest design. Subject population was SD rats induced by 40 mg/kg weight i.p of STZ. Thirty samples divided into 5 groups (C,X0,X1,X2,X3). Serum Hcy was measured by enzyme linked immunosorbent assay (ELISA), and plasma MDA by TBARS method. Data was analyzed by Wilcoxon and Kruskal Wallis test. 2 Result : serum level of Hcy before and after supplementation in group C: 22,5 μmol/L, 21 μmol/L respectively; group X0: 29 μmol/L, 23 μmol/L repectively; group X1: 24 μmol/L, 18 μmol/L respectively; group X2: 29 μmol/L,18 μmol/L respectively; group X3 : 21 μmol/L, 15 μmol/L respectively. Serum Hcy levels was significantly different in group X3 before and after 8 ppm of folate supplementation (p=0,043). Serum Hcy level decrease in treatment and control group not significantly different (p=0,50). Plasma MDA levels before and after treatment in group C: 24,32 μmol/L, 26,58 μmol/L respectively; group X0: 30,77 μmol/L, 32,69 μmol/L respectively; group X1: 33,65 μmol/L, 32,05 μmol/L respectively; group X2: 30,13 μmol/L, 40,39 μmol/L respectively; group X3: 29,49 μmol/L,38,84 μmol/L respectively. Increase of plasma MDA level not significantly different between treatment and control group (p=0,45) Conclusion: folate supplementation in SD rats induced by several dose of STZ can reduce serum Hcy level, but has no effect on plasma MDA level, this might be concern with other source of oxidative stress beside lipid peroxide caused by HHcy. Keywords: folate, homocystein, MDA,rats, DM.