Protective Effect of Chlorogenic Acid on Human Sperm: In Vitro Studies and Frozen-Thawed Protocol.

The study evaluated the chlorogenic acid (CGA) antioxidant potential on oxidative stress (OS) induced in vitro in human spermatozoa and during cryopreservation procedure. Swim-up selected spermatozoa were treated with 100 µM CGA, 100 µM HO to induce lipid peroxidation (LPO), and with both compounds and the effects on mitochondrial membrane potential (MMP) by JC-1, DNA integrity by acridine orange (AO), and sperm ultrastructure by transmission electron microscopy (TEM), were evaluated. CGA antioxidant activity was assessed by measuring malondialdehyde (MDA) and F-isoprostanes (F-IsoPs) in the media. The CGA protective activity and the immunolocalization of Phospho-AMPKα (Thr172) were explored in frozen-thawed sperm. CGA was not toxic for sperm motility, DNA integrity and MMP. The increase in MDA ( < 0.05) and F-IsoPs ( < 0.001), DNA damage ( < 0.01) and low MMP ( < 0.01) levels after HO treatment were reduced in presence of CGA as well as the percentage of broken plasma membranes ( < 0.01) and altered acrosomes ( < 0.01) detected by TEM. Treated frozen-thawed spermatozoa showed increased sperm motility ( < 0.01), DNA integrity ( < 0.01), MMP ( < 0.01), reduced MDA ( < 0.01) and increased sperm percentage with Phospho-AMPKα labelling in the head ( < 0.001). CGA can be used to supplement culture media during semen handling and cryopreservation where OS is exacerbated.