Diurnal variation in sperm DNA fragmentation: analysis of 11,382 semen samples from two populations and in vivo animal experiments.

Diurnal variation in sperm DNA fragmentation: analysis of 11,382 semen samples from two populations and in vivo animal experiments. Chronobiol Int. 2019 Aug 16;:1-9 Authors: Ni W, Liu K, Hou G, Pan C, Wu S, Zheng J, Cao J, Chen Q, Huang X Abstract Circadian rhythms have been found in some reproductive functions phenotypes but remain unclear for sperm DNA fragmentation index (DFI). The present study aims to investigate the diurnal variation of DFI in mice model and men sperm. Adult male mice were sacrificed for sperm DFI with Sperm Chromatin Structure Assay (SCSA) in 24 hours at 6 evenly distributed time points. A cosinor pattern of DFI was observed with a nadir at zeitgeber time 10 AM. In a community population with 630 semen samples collected between 8 AM and 20 PM, the temporal variation of DFI also fit a cosinor pattern with a - 343° acrophase and a nadir at 11 AM (P = .031). In a reproductive-medical-center dataset of 10752 semen samples collected between 7 AM and 11 AM, the decreasing trend of DFI was also confirmed. For the males with multiple samples, intra-individual comparison between different timepoints was performed, and each consecutive hour after 7 AM was also associated with 2.5 (95% CI: -1.0, 5.9)% lower DFI by SCSA or 4.9 (1.9, 7.8)% lower DFI by SCD. Our study reveals a daily diurnal variance in sperm DFI which may suggest a practical approach to get more qualified sperms for natural or assisted reproduction. Ab...
Source: Chronobiology International - Category: Biology Authors: Tags: Chronobiol Int Source Type: research