Poliformismos dos genes VEGF, MTHFR e MTR e fatores de risco na doença arterial coronária

Abstract

Coronary atherosclerosis results from interaction among environmental and genetic risk factors. In this sense, the objective of this study was to investigate the frequencies of VEGF gene polymorphisms, related to the development of new vessels, and of MTHFR e MTR genes polymorphisms, involved in the homocysteine metabolism (Hcy), associated to the formation of atherosclerosis lesions, in 175 patients with coronary artery disease (CAD) and 108 control individuals with no angiographic signs of the disease. Plasma Hcy, folate and methylmalonic acid (MMA), besides micronutrients ingestion required for Hcy metabolism were also analyzed. The risk factors for DAC were arterial hypertension (P=0.021), diabetes (P=0.029), smoking (P=0.006) and HDLc levels<40 mg/dL (P=0.0003). The altered VEGF -2578CC genotype was observed in higher frequency in patients with three damaged arteries (P=0.008). MTHFR 1298AA genotype was associated with decreased folate levels in the group with CAD (P=0,010). MMA mean levels were significantly higher in the group with CAD in relation to the control (P=0.048). Vitamin B12 deficiency was more frequently observed in CAD group (P=0,004). A positive correlation among MMA levels and Hcy concentrations was observed in the group with CAD (P=0.001), as well as in the control group (P=0.020). MMA mean levels were significantly higher in individuals with hyperhomocysteinemia in both groups CAD (P=0.0063) and control (P=0.013). Individuals with vitamin B12 deficiency presenting higher Hcy levels (P=0,007).Micronutrients ingestion levels did not differ significantly among the groups (P>0.05) and did not present association with Hcy, folate and MMA plasma levels (P>0.05). The obtained results have suggested that decreased expression of VEGF resultant of altered VEGF 2578A allele is a risk factor for atherosclerosis. Vitamin B12 deficiency, provided by the MMA quantification, showed to be an important risk factor either for hyperhomocysteinemia or for CAD.