Human sperm decondensation in vitro in the presence of sulfated glycosaminoglycans: a predictor of alterations in chromatin packaging in infertile patients?

LOVAGLIO MARÍA; CAMBIASSO MAITE YAEL; VALIENTE CARLA; GALOTTO CAMILA

Buenos Aires

Congreso; Reunión conjunta de sociedades de biociencias; 2018

Previous results from our laboratory suggested an interaction between heparinsulfate/heparin (HS/H) and dermatan sulfate (DS) in chromatin decondensationin vitro of spermatozoa obtained from normospermic donors. The aim of thisstudy was to evaluate such an interaction in infertile patients and its possiblerelationship to sperm protamine content. Sperm samples were obtained from 19patients undergoing assisted reproduction. Swim-up spermatozoa weredecondensed in vitro with 10 mM GSH and 46 μM H or DS for 15, 30 and 60minutes. % decondensation (D) was determined by phase contrast microscopy.In 11/19 patients, sperm nuclear proteins were extracted and analyzed by acidPAGE to determine protamine content (P1+P2) and P1/P2 ratio. There weredifferences among patients in sperm decondensation kinetics (D60/D30) with Hand DS. H distinguished 2 groups of patients: Fast decondensers (1.07±0.05,n=12), similar to normospermic donors, reached maximum decondensation at30 minutes and Slow decondensers (1.86±0.05, n=7, p=0.016, cutoff value 1.5)did not. DS, on the other hand, allowed the identification of 3 groups of patients:F (0.92±0.07, n=8), S (1.66±0.08, n=4) and Very Slow decondensers(3.46±0.60, p=0.0001 vs Slow, n=7). In the 11 patients whose protamines wereanalyzed by PAGE, median P1+P2 content was 553 (InterQuartile range 356-654) ng/106 sperm (normospermic control 680 ng/106 sperm) with P1/P2 = 0.41(IQ 0.29-0.78) (control 1.1). P1/P2 correlated (Spearman) with P1+P2 (r=0.697,p=0.02) and P1 (r=0.957, p