Paroxetine increases brain-derived neurotrophic factor in postmenopausal women

Objective: Menopause is marked by a decline in ovarian function resulting in one or more climacteric symptoms. In the last few years, attention has been focused on the use of selective serotonin reuptake inhibitors (SSRIs) in the treatment of vasomotor symptoms associated with the menopausal transition. Thanks to the recent findings on the interaction between the serotoninergic system and neurotrophins, it has been suggested that brain-derived neurotrophic factor (BDNF) could contribute to the activity of SSRIs. Moreover, because endogenous gonadal hormones modulate both BDNF expression and serotonin biosynthesis and bioavailability and regulate brain functions like affective and cognitive functions, we proposed to evaluate the effects of a treatment with paroxetine, an SSRI, in a group of postmenopausal women and to clarify the possible relationship between paroxetine, plasma BDNF levels, and climacteric symptoms. Methods: A total of 119 postmenopausal women (age, 46-60 y; menopause age, 1-20 y) were included; 89 took paroxetine 10 mg/day for 6 months and 30 took estrogen + progestogen therapy (EPT) for 6 months. Blood samples were taken before the beginning of the therapy and at 3 and 6 months. The Green Climacteric Scale questionnaire was used to follow up women's clinical conditions. Results: Plasma BDNF levels significantly increased after 3 and 6 months of therapy (P < 0.001), although a negative correlation between plasma BDNF level and both age and menopause age persisted throughout the treatment. Moreover, a significant reduction in the Greene Climacteric Scale score was observed. In the EPT group, the plasma BDNF level significantly increased after 6 months of therapy. The plasma BDNF levels after 6 months of paroxetine were significantly lower than those after 6 months of EPT. Conclusions: The present data suggest that a low dose of paroxetine is effective in enhancing plasma BDNF levels, and this increase might have a role in improving climacteric symptoms, highlighting the possible role of BDNF in endocrinological and cognitive functions.