The Effects of of Myoinositol on Standard Parameters, Oxidative Stress and DNA Fragmentation of Human Cryopreserved Sperm

Cryopreservation has been extensively used in assisted reproductive technology and it is an important task to improve current methods of sperm cryopreservation. Myoinositol is involved in several systemic processes and in mechanisms of signal transduction in the plasma membrane as precursor of second messengers. On the malereproductive function, MYO appears to regulate seminal plasma osmolarity and also sperm maturation, motility, capacitation and acrosome reaction. Recently an antioxidant action has also been suggested. The aim of this study is to evaluate the beneficial effect of MYO supplement in freezing media on the post thaw sperm quality. Semen samples from 40 normozoospermic men were divided into two aliquots and frozen with 2mg/ml MYO free /or supplemented freezing medium. Post thaw process, computer-aided semen analysis was used to analyze sperm motility and morphology. Reactive oxygen species (fluorometry of DCFH-DA), total antioxidant capacity, lipid peroxidation(colorimetric assay by ELISA reader) and DNA fragmentation (TUNEL staining) were evaluated. MYO significantly improved progressive motility and normal morphology in treated samples (P < 0.05). Lipid peroxidation can be precluded in samples frozen with MYO supplemented freezing media (P < 0.05). While MYO did not affect significantly the amount of ROS (P > 0.05), it was associated with a significant increase in total antioxidant capacity (P < 0.05). In MYO treated samples, DNA fragmentation was lower thancontrol ones (P < 0.001). The findings support the use of 2mg/ml myoinositol supplemented freezing media in sperm cryopreservation to increase sperm quality after freezing-thawing procedures.

Keywords:

Myoinositol , Human sperm cryopreservation , Sperm parameters , Oxidative stress , DNA fragmentation