Beta-defensin 106A

Objective: To evaluate the effect of smoking on sperm functional quality and seminal plasma proteomic profile. Patients and methods: Sperm functional tests were performed in 20 non-smoking men with normal semen quality, according to the World Health Organization (2010) and in 20 smoking patients. These included: evaluation of DNA fragmentation by alkaline Comet assay; analysis of mitochondrial activity using DAB staining; and acrosomal integrity evaluation by PNA binding. The remaining semen was centrifuged and seminal plasma was used for proteomic analysis (liquid chromatography-tandem mass spectrometry). The quantified proteins were used for Venn diagram construction in Cytoscape 3.2.1 software, using the PINA4MS plug-in. Then, differentially expressed proteins were used for functional enrichment analysis of Gene Ontology categories, Kyoto Encyclopedia of Genes and Genomes and Reactome, using Cytoscape software and the ClueGO 2.2.0 plug-in. Results: Smokers had a higher percentage of sperm DNA damage (Comet classes III and IV; P < 0.01), partially and fully inactive mitochondria (DAB classes III and IV; P = 0.001 and P = 0.006, respectively) and non-intact acrosomes (P < 0.01) when compared with the control group. With respect to proteomic analysis, 422 proteins were identified and quantified, of which one protein was absent, 27 proteins were under-represented and six proteins were over-represented in smokers. Functional enrichment analysis showed the enrichment of antigen processing and presentation, positive regulation of prostaglandin secretion involved in immune response, protein kinase A signalling and arachidonic acid secretion, complement activation, regulation of the cytokine-mediated signalling pathway and regulation of acute inflammatory response in the study group (smokers). Conclusion: In conclusion, cigarette smoking was associated with an inflammatory state in the accessory glands and in the testis, as shown by enriched proteomic pathways. This state causes an alteration in sperm functional quality, which is characterized by decreased acrosome integrity and mitochondrial activity, as well as by increased nuclear DNA fragmentation.

Study question: What are the effects of smoking on the functional aspects of the sperm, the levels of lipid peroxidation and the protein profile of seminal plasma in patients with varicocele? Summary answer: In men with varicocele, smoking is associated with altered semen quality, decreased sperm functional integrity and seminal oxidative stress. Alterations in seminal plasma protein profiles are also present and may explain the altered semen phenotype. What is known already: Varicocele is a major cause of male infertility. It reduces testicular blood renewal with a consequent accumulation of toxic substances. Thus, it can potentiate the toxic effects of environmental exposure to genotoxic substances such as those found in cigarette smoke. Study design, size and duration: A cross-sectional study was performed in 110 patients presenting with variococele to the Human Reproduction Section of the Sao Paulo Federal University (2006-2010). The patients were divided into a control group of non-smokers, a moderate smokers group and a heavy smokers group. Participants/materials, setting and methods: Semen parameters were analysed by standard methods. Sperm DNA integrity and mitochondrial activity were assessed by Comet assays and by 3,3'-diaminobenzidine deposition, respectively. The level of lipid peroxidation in semen was determined by malondialdehyde quantification. Proteomic studies were performed by 2D-electrophoresis and mass spectrometry. Main results and the role of chance: Both groups of smokers showed reduced semen quality in comparison with the control group. In the groups of smokers, sperm DNA integrity and mitochondrial activity were also decreased and lipid peroxidation levels were increased. Proteomic analyses revealed 20 proteins differentially expressed between the study groups. Limitations and reasons for caution: A study including smokers without varicocele is still warranted as these results apply only to smokers who present varicocele. Wider implications of the findings: Patients with varicocele who are exposed to tobacco smoking present more important alterations to semen quality and sperm functional integrity and show changes in the seminal plasma proteome. This suggests testicular, and possibly systemic, adverse effects of smoking. Study funding/competing interest(s): Funding for the study was provided by Fundação de Amparo à Pesquisa do Estado de São Paulo (Fapesp) (2007/59423-7) and by the Division of Urology, Human Reproduction Section at the São Paulo Federal University.

Objective: To analyze the seminal plasma proteome and biological functions associated with sperm functional alterations. Design: Cross-sectional study. Setting: University andrology and research laboratories. Patient(s): A total of 156 normozoospermic men. Intervention(s): Sperm mitochondrial activity, acrosome integrity, and DNA fragmentation were evaluated in a semen aliquot. Remaining semen was centrifuged, and seminal plasma was utilized for proteomic analysis (liquid chromatography-tandem mass spectrometry). Patients were divided into percentiles (15%) to form the following groups: substudy 1, high (control, n = 26) and low (study, n = 23) sperm mitochondrial activity; substudy 2, high (control, n = 23) and low (study, n = 22) sperm acrosome integrity; and substudy 3, low (control, n = 22) and high (study, n = 22) sperm DNA fragmentation. Groups were compared using univariate and multivariate analyses. Differentially expressed proteins were used for functional enrichment analysis. Main outcome measure(s): Seminal plasma proteome and postgenomic pathways are associated with several sperm functional traits. Result(s): In total, 506, 493, and 464 proteins were observed in substudies 1, 2, and 3, respectively. Enriched functions in substudy 1 were intramolecular oxidoreductase activity, aminoglycans catabolism, endopeptidases inhibition, lysosomes, and acute-phase response (study group). In substudy 2, main enriched functions were phospholipase inhibition, arachidonic acid metabolism, exocytosis, regulation of acute inflammation, response to hydrogen peroxide, and lysosomal transport (study group). In substudy 3, enriched functions were prostaglandin biosynthesis and fatty acid binding (study group). We proposed eight, six, and eight seminal biomarkers for substudies 1, 2, and 3, respectively. Conclusion(s): Seminal plasma proteome reflects sperm mitochondrial activity reduction, acrosome damage, and DNA fragmentation, with several postgenomic functions related to these alterations.