Recently, different “omics” techniques have been used to better understand male infertility conditions, helping the development of new diagnostic, therapeutic, and prognostics tools.5,6 The “omics” methods use high-throughput techniques to study several biological systems in a step-by-step fashion, progressing from the most basic information, the genome, passing through mechanisms that process this information, the epigenome, and the transcriptome, reaching the functional elements, the proteome, and ending in the net effects of their action, the metabolome and the phenome. This integrated approach relies heavily on chemical analytical methods, producing a massive amount of data that should be interpreted using bioinformatics and computational analysis tools in order to deliver clinically useful information.7 The unraveling of the physiopathologic mechanisms of varicocele in both collective and individual levels will definitively provide a precise clinical approach for the men who are affected by this condition, individualizing treatment based on their biological characteristics.
In this way, we applied a metabonomics technique to study the differences in the seminal metabolome among healthy, fertile, and infertile men with and without varicocele. Using hydrogen-1 nuclear magnetic resonance spectroscopy, we aimed to identify metabolites that were differentially expressed in these 3 groups of participants and to create statistical models capable of discriminating the groups.
We identified 19 metabolites that were important in group segregation. These metabolites were associated with the metabolism of amino acids, energy metabolism, and oxidative stress response. These findings suggest that the degree of damage to spermatogenesis caused by varicocele is associated with the compensatory response capability of each individual. That is, fertile men with varicocele have a better compensatory response to varicocele than infertile. Furthermore, using multivariate statistical tools, we created several metabonomics models that discriminated against the study groups with high accuracy.
We believe that our results will help to understand the metabolic pathways responsible for varicocele-induced male infertility, and will pave the way to the development of a more individualized approach for varicocele diagnosis and treatment.
Written by: Filipe Tenorio Lira Neto, Ronmilson Alves Marques, Alexandre de Freitas Cavalcanti Filho, Leslie Clifford Noronha Araujo, Salvador Vilar Correia Lima, Licarion Pinto, Ricardo Oliveira Silva
Department of Surgery, Universidade Federal de Pernambuco, Rua Guilherme Salazar, n 150, apt 601E, Recife, PE, ZIP 52061-275, Brazil. ., Fundamental Chemistry Department, Universidade Federal de Pernambuco, Av. Jornalista Anibal Fernandes, s/n° Cidade Universitária, Recife, PE, ZIP 50740-560, Brazil., Instituto de Medicina Integral Prof. Fernando Figueira, Rua dos Coelho, 300, Coelhos, Recife, PE, ZIP 50070-902, Brazil., Faculdade de Medicina de Olinda, Rua Dr. Manoel de Almeida Belo, n 1333, Olinda, PE, ZIP 53030-030, Brazil., Department of Surgery, Universidade Federal de Pernambuco, Hospital das Clínicas - Campus UFPE, Av. Prof. Moraes Rego,"s/n° - Bloco "A" - Térreo Cidade Universitária, Recife, PE, ZIP 50670-420, Brazil.
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