RESUMO
BACKGROUND: Inflammatory bowel diseases (IBDs) are multifactorial illnesses of the intestine, to which microorganisms are contributing. Among the contributing microorganisms, sulfate-reducing bacteria (SRB) are suggested to be involved in the process of bowel inflammation due to the production of hydrogen sulfide (H2S) by dissimilatory sulfate reduction. The aims of our research were to physiologically examine SRB in fecal samples of patients with IBD and a control group, their identification, the study of the process of dissimilatory sulfate reduction (sulfate consumption and H2S production) and biomass accumulation. Determination of biogenic elements of the SRB and evaluation of obtained parameters by using statistical methods were also included in the research. The material for the research consisted of 14 fecal samples, which was obtained from patients and control subjects. METHODS: Microscopic techniques, microbiological, biochemical, biophysical methods and statistical analysis were included. RESULTS: Colonies of SRB were isolated from all the fecal samples, and subsequently, 35 strains were obtained. Vibrio-shaped cells stained Gram-negative were dominant in all purified studied strains. All strains had a high percentage of similarity by the 16S rRNA gene with deposited sequences in GenBank of Desulfovibrio vulgaris. Cluster analysis of sulfate reduction parameters allowed the grouping of SRB strains. Significant (p < 0.05) differences were not observed between healthy individuals and patients with IBD with regard to sulfate reduction parameters (sulfate consumption, H2S and biomass accumulation). Moreover, we found that manganese and iron contents in the cell extracts are higher among healthy individuals in comparison to unhealthy individuals that have an intestinal bowel disease, especially ulcerative colitis. CONCLUSIONS: The observations obtained from studying SRB emphasize differences in the intestinal microbial processes of healthy and unhealthy people.
RESUMO
BACKGROUND: Oxidative stress is considered as one of the causes of male subfertility or infertility. Among antioxidant enzymes, the crucial role belongs to glutathione S-transferases (GSTs). Data on the biological role of GSTs in the defense mechanisms of sperm cells in fertile and infertile men are limited. AIM: The aim of this study was to demonstrate the functional role of GSTs in sperm cells on the model of H2O2-induced stress on human ejaculated spermatozoa obtained from both normospermic and pathospermic patients. SUBJECTS AND METHODS: We used a H2O2-induced stress on human ejaculated spermatozoa obtained from both normospermic and pathospermic patients. RESULTS: Here, we report the effect of GST inhibitor ethacrynic acid on sperm motility and viability. Pharmacological inhibition of sperm GSTs activity leads to spermal membrane damage and rejected in the loss of motility and decrease of viability. For similar treatment conditions, thiobarbituric acid reactive substance (TBARS) levels increased significantly leading to decrease in sperm motility and viability. It is suggested that these functional impairments are related to the intensification of lipid peroxidation as expressed by TBARS levels in spermal membranes after GST inhibitor treatment. CONCLUSION: This study provides evidence that sperm GSTs are important in the defense mechanism against oxidative stress. Evaluation of GSTs activity in sperm cells of infertile men can be helpful in fertility assessment and for the evaluation of treatment by antioxidants.
RESUMO
BACKGROUND: Infertility is an important worldwide problem which affects 10-15% of couples globally. Altered NO production has also been implicated in the pathogenesis of the male infertility. The present study was designed to evaluate the changes in the activity of NO-synthase (NOS) and arginase in spermatozoa of patients with infertility. METHODS: The total NOS, Ca2+-dependent constitutive (cNOS) and Ca2+-independent inducible (iNOS) activity and arginase activity were assessed in sperm cells of patients with different forms of pathospermia. RESULTS: We found a significant increase in iNOS activity, but significantly decreased cNOS and arginase activity in sperm cells of infertile men vs fertile, normozoospermic men (p<0.001). The arginase/NOS ratio significantly decreased compared to control group. The iNOS/cNOS ratio was drastically increased in patients with decreased fertility potential indicating predominance of iNOS. Men with leuko cytospermia were distinguished to have the most express iNOS activity. CONCLUSIONS: These observations provide evidence for a disturbed balance between the L-arginine metabolic pathways in sperm cells of infertile men. This imbalance includes the considerable activation of the inducible isoform of NO-synthase accompanied by significant inhibition of its constitutive isoform which indicates disturbances in NO production. In patients with decreased fertility potential the arginase/NOS was shifted towards predominance of iNOS-derived NO production.
