Hemodialysis decreases serum brain-derived neurotrophic factor concentration in humans.

In the present study we have evaluated the effect of a single hemodialysis session on the brain-derived neurotrophic factor levels in plasma [BDNF](pl) and in serum [BDNF](s) as well as on the plasma isoprostanes concentration [F(2) isoprostanes](pl), plasma total antioxidant capacity (TAC) and plasma cortisol levels in chronic kidney disease patients. Twenty male patients (age 69.8 ± 2.9 years (mean ± SE)) with end-stage renal disease undergoing maintenance hemodialysis on regular dialysis treatment for 15-71 months participated in this study. A single hemodialysis session, lasting 4.2 ± 0.1 h, resulted in a decrease (P = 0.014) in [BDNF](s) by ~42 % (2,574 ± 322 vs. 1,492 ± 327 pg ml(-1)). This was accompanied by an increase (P < 10(-4)) of [F(2)-Isoprostanes](pl) (38 ± 3 vs. 116 ± 16 pg ml(-1)), decrease (P < 10(-4)) in TAC (1,483 ± 41 vs. 983 ± 35 trolox equivalents, μmol l(-1)) and a decrease (P = 0.004) in plasma cortisol level (449.5 ± 101.2 vs. 315.3 ± 196.3 nmol l(-1)). No changes (P > 0.05) in [BDNF](pl) and the platelets count were observed after a single dialysis session. Furthermore, basal [BDNF](s) in the chronic kidney disease patients was significantly lower (P = 0.03) when compared to the age-matched control group (n = 23). We have concluded that the observed decrease in serum BDNF level after hemodialysis accompanied by elevated [F(2)-Isoprostanes](pl) and decreased plasma TAC might be caused by enhanced oxidative stress induced by hemodialysis.