Serum homocysteine levels, oxidative stress and cardiovascular risk in non-alcoholic steatohepatitis

Abstract

Introduction: Hyperhomocysteinemia is considered an independent risk factor for cardiovascular disease. Oxidative stress is one of the major pathogenic mechanisms in non-alcoholic fatty liver disease and atherosclerosis.

Aim: Our study aimed to evaluate serum homocysteine levels and oxidative stress in patients with biopsy-proven non-alcoholic steatohepatitis and possible association with cardiovascular risk measured by carotid artery intima-media thickness (c-IMT).

Patients and methods: 50 patients with non-alcoholic steatohepatitis and 30 healthy controls, age and gender matched, were recruited. Lipid profile, liver biochemical markers, serum homocysteine, vitamins B6 and B12, folic acid, glutathione (reduced and total), erythrocyte superoxide dismutase, whole blood glutathione peroxidase, malondialdehyde and carotid intima-media thickness were assayed.

Results: Patients had an altered lipid profile and liver biochemical markers; carotid intima-media thickness and serum homocysteine levels were significantly higher compared to controls, but there were no differences in folate, B12 and B6 vitamins levels. Patients had significantly lower levels of glutathione peroxidase activity, total and reduced glutathione and higher levels of malondialdehyde, but unchanged superoxide dismutase activity compared to control group. Also, serum homocysteine level showed significant positive correlation with waist circumference, body mass index, free cholesterol, triglycerides, LDL-cholesterol, amino transferases and negative correlation with reduced and total glutathione, superoxide dismutase and γ-GT.

Conclusion: Non-alcoholic steatohepatitis is an independent cardiovascular risk factor, associated with elevated homocysteine levels, oxidative stress and c-IMT. c-IMT could be used as an indicator of early atherosclerotic changes initiated by dyslipidemia and oxidative stress, while higher level of homocysteine might be an effect of liver damage.

Keywords: Cardiovascular risk; Carotid artery intima-media thickness; Homocysteine; Non-alcoholic steatohepatitis; Oxidative stress.