Perfil endócrino e reprodutivo de ratos machos em crescimento suplementados com prebióticos mananoligossacarídeos

Abstract

The aim of this study was to evaluate the effect of different mannan oligosaccharides (MOS) on the endocrine and reproductive profile of growing Wistar rats. A hundred and twenty eight 23-day- old male rats, weighing 45 grams, were randomly divided into four groups (n = 8): control group [basal diet]; MOS1 Group [basal diet + 1 g MOS 1 (mannan oligosaccharide derived from the cell wall of the yeast Saccharomyces cerevisiae, strain 1026, composed of 17% of α-mannans), per kg diet]; MOS2 Group 2 [basal diet + 0.4 g MOS 2 (active fraction, α-1,3 and α-1,6 derived from a mannan oligosaccharides, with 30% of α-mannans), per kg diet ]; and MOS3 Group [basal diet + 1 g of MOS 3 (β-glucans, mannans, mannose polymers, chitin (glucosamine polymer) and galactans (galactose polymer) derived from the yeast strain Saccharomyces cerevisiae) per kg diet]. Food and drinking water were provided ad libitum for 56 days. Histological evaluations of the reproductive system, as well as the doses of the hormones were evaluated in four experimental periods. The design was completely randomized in a 4x4 factorial design (4 treatments x 4 collection periods: 14, 28, 42 and 56 days after the start of administration of feed). To determine whether the scores of histological parameters differ between the experimental groups and between times, he used the nonparametric Kruskal-Wallis test, with contrasts by the Student-Newman-Keuls. For hormone concentrations, the data were submitted to linear regression considering the time in days as an independent variable and the serum levels as the dependent variable. For all analyzes we adopted a significance level of 5%. The groups supplemented with MOS showed higher testosterone concentrations, quantities of spermatozoa, sperm and radius of the seminiferous tubules and lower cortisol levels (P <0.05). It follows that prebiotics MOS derived from the cell wall of Saccharomyces cerevisiae in pubescent rats led to a change in steroidogenesis, evidenced by reduction of cortisol and increased plasma testosterone with an anticipation of sexual puberty verified by a higher proportion of spermatids and sperm and the further development of the seminiferous tubules.