A follicular fluid chondroitin sulfate proteoglycan improves the retention of motility and velocity of human spermatozoa.

Objective: To examine the effects of two proteoglycans of different structure, isolated from human follicular fluid (FF), on the motility of human spermatozoa.
Design: Normozoospermic semen samples and their swim-up sperm fractions were incubated in the presence of 0.4 mg/mL of a larger chondroitin sulfate proteoglycan (CS-PG) for 0, 3, 7, and 16 hours. The effects of a smaller heparan-CS-PG and the chondroitin sulfate side chains of the larger proteoglycan were also investigated in the same conditions. Sperm motility parameters were analyzed using a computer-aided sperm analysis system (CASA; Cryo Research Inc., New York, NY) RESULTS: The larger CS-PG caused an immediate increase in sperm linearity. After 3 and 7 hours, the retention of sperm motility, velocity, linearity, and amplitude of lateral head displacement have increased by an average of 13% compared with the control samples. After a 16-hour incubation, the retention of the motility properties was improved by approximately 40% (range, 27% to 50%) in the samples containing proteoglycan. The effects of the isolated glycosaminoglycan side chains were much lower than those of the intact proteoglycan. The heparan-CS-PG did not affect sperm motility.
Conclusion: A CS-PG from FF increases retention of motility and velocity of human sperm. These physiological effects may enhance the fertilizing efficiency of spermatozoa in the female reproductive tract.