The effects of coenzyme Q10 and curcumin supplementation in freezing medium for human sperm cryopreservation.

BACKGROUND

Despite its routine and frequent application, cryopreservation of human sperm is far from the desired efficacy, as freezing and thawing impair motility, viability, acrosomal unity, and DNA integrity.

OBJECTIVES

In this study, the authors aimed to investigate whether adding antioxidants, coenzyme Q10, and curcumin into the freezing medium provide better efficacy in the cryopreservation of human sperm.

METHODS

The semen samples from 40 healthy men aged 18-45 were collected in sterile containers by masturbation. Samples within normal reference values for sperm concentration (≥15 million/mL) and motility (progressive motile ≥ 32% and total motility ≥ 40%) were included in the study. Semen samples were equally divided into five groups and evaluated; i) pre-freezing sperm suspension, ii) frozen-thawed control (Ctrl) without any supplementation in freezing medium, iii) frozen-thawed with curcumin supplementation of 0.25 mM (Cur), iv) frozen-thawed coenzyme Q10 supplementation of 25 µM (CoQ10) and v) frozen-thawed curcumin (0.25 mM) plus coenzyme Q10 (25 µM) supplementation (CurCoQ10) into the freezing medium. Liquid nitrogen vapour freezing and rapid thawing were performed in each group (ii-v). Sperm motility, viability, acrosome integrity, and DNA fragmentation rates were compared and ultrastructural evaluations by transmission electron microscopy were undertaken between the groups. Additionally, the total antioxidant capacity/total oxidant capacity values were measured.

RESULTS

According to CASA results, progressive motility was significantly higher in the CoQ10 group (9.4 ± 7.6) when compared with the Ctrl (7.1 ± 6.3), Cur (6.4 ± 4.8) and CurCoQ10 (8.1 ± 7.7) groups (p < 0.05). Flow cytometry results showed no difference in the viability and acrosome integrity values after thawing, but DNA fragmentation was significantly increased in the curcumin-added groups (p < 0.05). Acrosomal changes and sub-acrosomal defects were seen in all groups after thawing at the ultrastructural level. Mitochondrial membrane structure was preserved in CoQ10 and CurCoQ10 groups.

CONCLUSIONS

Our results suggested that sperm ultrastructural morphology and motility were better preserved in the CoQ10 group during cryopreservation. In curcumin groups, DNA fragmentation and head defects were increased.