Serum homocysteine: relationship with circulating levels of cortisol and ascorbate

High serum levels of homocysteine and cortisol are independent risk factors for several pathologies and their levels can be regulated by some vitamins. Since the relationship between serum concentrations of homocysteine, cortisol and ascorbate has not been assessed in healthy individuals to date, it was the topic of the present work.

The study group was composed of 20 men and 40 women aged >50 years. Blood samples were collected and serum concentrations of the analytes were quantified.

Serum homocysteine levels correlate positively with cortisol (r = 0.36, p <0.01) and age (r = 0.49, p < 0.001), and negatively with ascorbate (r = -0.30, p < 0.05) and folate (r = -0.31, p < 0.05). A negative correlation between serum levels of cortisol and ascorbate (r = -0.30, p < 0.05) was also observed. Multiple linear regression analysis showed that the best independent predictors of serum homocysteine concentration were cortisol (beta = 0.319, p < 0.003), age (beta = 0.529, p < 0.001) and folate (beta = -0.338, p < 0.001). When subjects were divided into tertiles according to their homocysteine concentration, the highest tertile of homocysteine concentration has also higher cortisol (p < 0.005) and lower ascorbate (p < 0.05) concentrations compared with the lowest tertile of homocysteine concentration.

The association between serum concentrations of homocysteine, cortisol and ascorbate suggests interaction between circulating levels of these molecules.