Inositol activity in oligoasthenoteratospermia--an in vitro study

Oligoasthenoteratospermia, a reduction in motilty and number of spermatozoa and a change in their morphology, is one of the most relevant causes of infertility in men. One of the factors, which may influence male infertility is linked to the production of reactive oxygen species (ROS) by morphologically altered spermatozoa. Spermatozoa are more susceptible than other cell species to the detrimental activity of these chemical compounds. In particular ROS can affect motility, morphology and DNA stability of spermatozoa.

In the present in vitro study the role of a natural substance, inositol, has been investigated as a possible antioxidant agent both for the systemic treatment of male infertility and for the improvement in the in vitro quality of the sperm used for the fertilization applied to medically assisted reproductive procedures.

The collected samples, belonging to subjects suffering from oligoasthenoteratospermia and of healthy subjects were submitted to phase constrast microscopy in order to evaluate spermatozoa motility, treated with inositol 2 mg/ml and then submitted to scansion electron microscopy (SEM) and to transmission electron microscopy (TEM). SEM allowed to study both the surface morphology of the biological samples and the changes induced on them by the treatment with inositol. TEM allowed to study ultrastructural details of the biological samples.

In the samples of subjects suffering from oligoasthenoteratospermia the spermatozoa appear entirely covered with an amorphous fibrous material, that gives an excessive viscosity to the seminal fluid, and reduces or avoids cell mobility. The micrographs of these samples show that the mitochondria, in their intermediate tract, appear to be altered with markedly damaged cristae. After treatment with inositol the pathologic samples clearly shows the absence of the amorphous material, perhaps due to a variation in seminal fluid pH. Furthermore, they show the presence of mitochondria morphologically more similar to control specimen mitochondria, with less damage involving mitochondrial cristae.

These preliminary data appear to suggest that inositol, on account of its antioxidant activity, could preferentially aim at the mitochondrium. Further studies are requested to the purpose of better defining the combination between ROS values of the samples, inositol in vitro treatment and oligoasthenoteratospermia.