Serum folate is significantly correlated with plasma cysteine concentrations in healthy industry workers.

BACKGROUND: A low concentration of serum folate is associated with an increased risk of cardiovascular disease. Extracellular cysteine is involved in aging, cancer and cardiovascular disease. The relationship between serum folate and plasma cysteine is poorly understood. Therefore, we investigated this relationship in industry workers, whose health has economic implications.
METHODS: The concentration of serum folate was determined by the Access ImmunoAssay System Sanofi Pasteur. Plasma cysteine and homocysteine were measured by an ion-pair HPLC method. The concentrations of serum triglycerides were determined by an enzymatic colorimetric method.
RESULTS: We detected a positive correlation between the concentration of serum folate and plasma cysteine, whereas the concentration of serum folate was negatively correlated with plasma homocysteine and serum triglycerides. In a multiple regression analysis with adjustment for age, BMI and smoking, serum folate as the dependent variable exhibited a strong relationship with plasma cysteine, and a negative relationship with plasma homocysteine and serum triglycerides.
CONCLUSION: We observed significant correlations between serum folate, plasma cysteine and serum triglyceride concentrations in industry workers, implying that folate may modulate key aspects of the body's cysteine and lipid metabolism.