The relationship of folate deficiency, hyperhomocysteinemia and glutathione metabolism in hypertensive patients

Abstract

Hypertension (HTN) is often accompanied by folic acid (FA) deficiency and hyperhomocysteinemia (HHcy). Reduced glutathione (GSH) and dependent enzymes determine the state of cellular antioxidant and redox systems in cardiovascular pathology. The aim of our work is to assess the relationship between the status of FA and the presence of HHcy with enzymes of glutathione metabolism and the redox state of erythrocyte glutathione in HTN. Design and methods. In blood plasma samples from 43 HTN patients admitted to the clinic of Pavlov University, the concentration of FA and total homocysteine (oHcy) was determined. We also evaluated the level of GSH, the activity of glutathione peroxidase and glutathione reductase (GR) in erythrocytes. Results. In the whole group, GR activity positively correlated with the concentration of FA (R = 0,415; p = 0,001). A significant decrease in GR activity (U/g Hb) was found in the subgroup with the low level of FA [0,8 (0,5–1,1)] compared with the subgroup without a FA deficiency [1,2 (0,9–2,0)]. The GSH level (μM/g Hb) was also lower (p < 0,018) in the subgroup with FA deficiency [1,3 (0,9–2,1)] compared with the subgroup with normal FA levels [1,8 (1,5–4,6)]. A significant decrease in the level of GSH and GR activity in the subgroup with HHcy was found compared with the corresponding parameters in the subgroup without HHcy. However, even in the absence of HHcy patients with FA deficiency demonstrated a significant decrease in GR activity compared to patients without FA deficiency. In this case, GR positively correlated with FA (R = 0,564; p = 0,03). Conclusions. The deficiency of FA can increase the deficiency of GR activity, regardless of the level of oHcy. The indicator of GR activity in erythrocytes can be considered as a possible marker of functional deficiency of FA in the absence of HHcy.