Effect of bamboo culm extract on oxidative stress and genetic expression: bamboo culm extract ameliorates cell adhesion molecule expression and NFkappaB activity through the suppression of the oxidative stress.

BACKGROUND & AIMS: This study was designed to investigate whether bamboo culm extract (BCE) supplementation may ameliorate risk factors of cardiovascular diseases, such as hypercholesterolemia.

METHODS: Oxidative stress and inflammatory mediators in plasma, livers of C57BL/6 mice fed high-cholesterol diet and calf pulmonary artery endothelial (CPAE) cells. Briefly, C57BL/6 mice were fed the high-cholesterol diet which was supplemented with 1% (w/w), or 3% (w/w) of BCE for 16 weeks. The concentration of total cholesterol, LDL-cholesterol, HDL-cholesterol level and atherogenic index were measured. Plasma TEAC value, hepatic thiobarbituric acid reactive substances (TBARS), protein carbonyl values and hepatic antioxidant enzyme activities, such as Cu,Zn-superoxide dismutase (SOD), Mn-SOD, glutathione peroxidase (GSH-Px), GSH reductase and catalase were determined. In addition, hepatic nuclear factor kappa B activities were detected. In the calf pulmonary artery endothelial (CPAE) cells stimulated with lipopolysaccharide, the expression of vascular cell adhesion molecule-1 (VCAM-1) and intracellular cell adhesion molecule-1 (ICAM-1) were measured.

RESULTS: Plasma cholesterol level was decreased, while HDL-cholesterol was increased, thus atherogenic index was lowered in BCE-supplemented animals. Plasma trolox equivalent and hepatic thiobarbituric acid reactive substances and protein carbonyl values were lowered significantly in BCE groups (p<0.05) in a dose-dependent manner. Hepatic antioxidative enzyme activities, such as Cu,Zn-superoxide dismutase (SOD), Mn-SOD, glutathione peroxidase (GSH-P), GSH reductase, and catalase were elevated in mice fed BCE-supplemented diets (p<0.05). Nuclear factor kappa B activities of livers and vascular cell adhesion molecule-1 and intracellular cell adhesion molecule-1 expressions in CPAE cells stimulated with lipopolysaccharide were significantly lowered in BCE groups (p<0.05).

CONCLUSION: These results suggest that BCE supplementation may modulate lipoprotein composition and attenuate oxidative stress by elevated antioxidative processes, thus suppressing inflammatory mediator activation as possible mechanism of its anti-atherogenic effect.