The Influence Of Dietary L-arginine Supplementary On The Content Of NF-κB And Expression Of VCAM-1 In The Aorta Of Hypercholesterolemic Rats

Object : Atherosclerosis(AS) has been regarded as an -inflammatory disease . Besides its action on vasomotor tone regulation, nitric oxide (NO) is recognized to be an anti-inflammatory molecule. Nuclear factor kappa B(NF-KB) / one of the most important transcription factors, plays a key role in the expression of many inflammatory mediators, some of which, such as adhesion molecules, contribute to the development of atherosclerosis. Some studies had suggested that NO may be anti-atherogenic through its inhibitory effects on NF- K B .Most of these studies undertook with NO donors, but few with L-arginine. This study is designed to investigate the anti-inflammatory effect of L-arginine on content of nuclear factor kappa B and expression of VCAM-1 in the aorta of hypercholesterolemic rats.Methods : Thirty male Wistar rats were randomized into three groups: Group NC was given normal diet ( NC, n=10), group CChypercholesterolemic diet (CC, n=10) and group AC hypercholesterolemic diet supplemented with 3% L-arginine in drinking water (AC, n=10). After 12 weeks blood samples were collected for biochemical studies; serum nit rate (NO2-) production was chosen as a marker of NO production in vivo. The aortas were harvested for Western Blot and immuhischemical. Pearson correlation was done to analyse the correlation between the content of NF-KB and the expression of VCAM-1.Results: Serum cholesterol concentrations of rats of the AC and CC groups were no significant difference (P>0.05), but significantly higher than those of the NC group (P<0.05). Serum nitric oxide concentrations of the NC and AC groups were no significant difference (P>0.05), but significantly higher than those of the CC group (P<0.05). Dietary L-arginine supplementation (group AC) significantly reduced the content of nuclear factor kappa B and inhibited the expression of VCAM-1 ( vs group CC, P<0.05) . The correlation coefficient between the content of NF-K B and the expression of VCAM-1 was 0.942 by Pearson correlation (P<0.01).Conclusion : 1. Dietary L-arginine supplementation significantly reduced the content of nuclear factor kappa B in the aorta of hypercholesterolemic rats and restored the levelof nitric oxide. 2. Dietary L-arginine supplementation significantly inhibited the expression of VCAM-1 in the aorta of hypercholesterolemic rats. 3.Inhibitory effect of dietary L-arginine supplementation on content of nuclear factor kappa B and expression of VCAM-1 may be one of the mechanisms of the anti-atherogenic effect of L-arginine.