Update on the proteomics of male infertility: A systematic review

Abstract

ObjectiveTo assess the role of differentially expressed proteins as a resource for potential biomarker identification of infertility, as male infertility is of rising concern in reproductive medicine and evidence pertaining to its aetiology at a molecular level particularly proteomic as spermatozoa lack transcription and translation. Proteomics is considered as a major field in molecular biology to validate the target proteins in a pathophysiological state. Differential expression analysis of sperm proteins in infertile men and bioinformatics analysis offer information about their involvement in biological pathways.Materials and methodsLiterature search was performed on PubMed, Medline, and Science Direct databases using the keywords ‘sperm proteomics’ and ‘male infertility’. We also reviewed the relevant cross references of retrieved articles and included them in the review process. Articles written in any language other than English were excluded.ResultsOf 575 articles identified, preliminary screening for relevant studies eliminated 293 articles. At the next level of selection, from 282 studies only 80 articles related to male infertility condition met the selection criteria and were included in this review.ConclusionIn this molecular era, sperm proteomics has created a platform for enhanced understanding of male reproductive physiology as a potential tool for identification of novel protein biomarkers related to sperm function in infertile men. Therefore, it is believed that proteomic biomarkers can overcome the gaps in information from conventional semen analysis that are of limited clinical utility.

Round cells do not contaminate or mask human sperm proteome in proteomic studies using cryopreserved samples

“…Proteomics provides new insights into the protein composition and expression at the subcellular level. In the last decade, several proteomic studies have been conducted using spermatozoa and seminal plasma (Amaral et al, ; Panner Selvam, & Agarwal, ; Panner Selvam, Agarwal, Sharma, & Samanta, ; Samanta et al, ) to understand the molecular pathways associated with male infertility and identification of potential protein biomarkers. High‐throughput instruments such as MALDI‐TOF and LC‐MS/MS systems are widely used to identify the proteomic profile of spermatozoa (Agarwal, Durairajanayagam, Halabi, Peng, & Vazquez‐Levin, ; Kosteria, Anagnostopoulos, Kanaka‐Gantenbein, Chrousos, & Tsangaris, ; du Plessis, Kashou, Benjamin, Yadav, & Agarwal, ).…”

“…Subsequently, the liquefied samples were subjected to macroscopic semen analysis, including as volume, colour, pH and viscosity. In the case of hyperviscous samples, viscosity was broken down mechanically by pipetting to avoid the interference of proteolytic enzymes in the proteomic analysis (Panner Selvam, & Agarwal, ; Panner Selvam, Agarwal, Sharma, & Samanta, ). Microscopic semen parameters such as sperm concentration, motility and presence of round cells were determined according to the World Health Organization (WHO) guidelines (WHO, ).…”

“…Recent advances in the field of proteomics constitute a new approach for the selection of protein biomarkers associated with sperm function. These markers have great potential in understanding the molecular basis of male infertility (Panner Selvam, & Agarwal, ; Panner Selvam, Agarwal, Sharma, & Samanta, ). However, there are some discrepancies in the processing of semen samples for proteomic‐based experiments (Martínez‐Heredia, Estanyol, Ballescà, & Oliva, ; Wang et al, ).…”

Male Infertility is a Women’s Health Issue—Research and Clinical Evaluation of Male Infertility Is Needed

“…Sperm are transcriptionally and translationally inert cells that are dependent on already existing proteins. Hence, identifying the sperm proteome using mass spectroscopy may play a crucial role in determining a man's fertility potential [82]. Aberrant expression of sperm proteins was reported to affect the molecular mechanisms associated with motility, capacitation, acrosomal reaction, and sperm-oocyte interaction in unexplained male infertility cases [83].…”

Imaging mass spectrometry and shotgun proteomics reveal dysregulated pathways in hormone induced male infertility

“…Large scale -omics techniques allow a much deeper molecular understanding of the pathways and proteins involved in the phenotype. So far, most proteomic studies have focussed on sperm or seminal fluids (Panner Selvam & Agarwal, 2018). Only very few proteomic studies of the testis have been performed, which were in addition severely limited in terms of the number of proteins identified.…”