Sperm mitochondrial dysfunction and oxidative stress as possible reasons for isolated asthenozoospermia.

Reduced sperm motility, defined as asthenozoospermia, is a frequent cause of male infertility, and is mainly connected with the dysfunction of sperm mitochondria. The aim of this study was to identify the proteins, and thereby the metabolic pathways, responsible for asthenozoospermia, using 2-DE and MALDI-TOF MS, and correlate the results obtained with those of two mitochondrial tests: JC-1 and MitoSox Red. The JC-1 test was performed to test sperm mitochondrial activity, and the MitoSox Red test was performed to check whether the observed sperm poor motility is associated with mitochondrial reactive oxygen species (ROS) production. To identify proteins strictly connected with reduced sperm motility, men with isolated asthenozoospermia (n = 4 versus 10 normozoospermic controls) alone were included in the study. The proteomic analyses resulted in the identification of 25 sperm proteins that are differentially expressed in asthenozoospermic individuals. Most of the identified proteins were downregulated and were involved in energy production; however, we have also identified structural sperm proteins and proteins secreted by the epididymis. The latter, together with the results from MitoSox Red assay, may provide insights into the pathophysiological basis of asthenozoospermia.

Mapping of polar fox renal cortex proteins using two-dimensional gel electrophoresis and mass spectrometry--a preliminary study.

The aim of the present study was to establish protein map of polar fox (Alopex lagopus) renal cortex. Kidney cortex proteins of isoelectric point ranging from 3 to 10 were analysed using two-dimensional electrophoresis and MALDI-TOF mass spectrometry. Sixteen protein spots corresponding to thirteen different gene products were identified. These proteins were divided into following groups: lipid and fatty acid metabolism, amino acid metabolism, energetic pathways, regulatory proteins, transport proteins and structural proteins. This is the first attempt to create reproducible 2-D map, of renal cortex proteins characteristic for polar foxes, used as animal model for carnivores. It is worth emphasizing that the results of this study may broaden currently available protein databases.