The effect of hyperprolactinemia and its treatment on oxidative stress.

Introduction: There are few studies investigating oxidative stress in hyperprolactinemia. We aimed to analyze the associations between hyperprolactinemia, its treatment, and oxidative stress parameters.

Methods: Twenty patients who had hyperprolactinemia secondary to a prolactin-secreting pituitary tumor, and 20 age- and BMI-matched healthy controls were prospectively included. Patients were studied at recruitment and six months post-treatment. Markers indicating protein oxidation and antioxidant system were analyzed.

Results: Serum prolactin level in the patient group (13 female, 7 male) was significantly higher than controls. Myeloperoxidase (MPO) activity and advanced oxidation protein product (AOPP) levels were comparable between the groups, while pyrrolized protein, and protein carbonyl compound (PCC) levels were significantly higher, and thiol levels lower in the patients at baseline. A decrease in prolactin levels along with improvements in estradiol (in females) and testosterone (in males) levels were observed following treatment. After treatment of hyperprolactinemia a significant decrease in AOPP, PCC, pyrrolized protein, and an increase in thiol levels were observed. MPO activity remained stable.

Discussion: In addition to reproductive dysfunctions and altered sex hormones, hyperprolactinemia is associated with oxidative stress, which improves four to six months after cabergoline treatment.