Metabonomic analysis of fatty acids in seminal plasma between healthy and asthenozoospermic men based on gas chromatography mass spectrometry

Abstract

The mechanism of asthenozoospermia remains unclear. The knowledge of the metabolism of fatty acids in seminal plasma is important and meaningful for the pathological study of asthenozoospermia. We present an optimised assay of extraction and derivatisation followed by GC/MS to analyse metabolites, especially fatty acids, in seminal plasma from healthy and asthenozoospermic men. Eighty-nine peaks including 17 kinds of fatty acids were analysed and identified in the chromatogram. The GC/MS data were analysed using t test, fold change and partial least squares discriminant analysis to explore the potential biomarkers of asthenozoospermia. Seven metabolites in asthenozoospermic group were found to be significantly different from those in the normal group (with p < .05, fold change >1.2 and variable importance for projection >1). Of which, high levels of oleic acid and palmitic acid in seminal plasma from asthenozoospermic men may indicate a membrane metabolism disorder in spermatozoa and the lack of valine in the asthenozoospermic group may contribute to poor sperm motility. The results may facilitate the understanding of the role of fatty acids and amino acids in asthenozoospermia and provide solid foundation for further pathological study of asthenozoospermia.

Metabolomic markers of fertility in bull seminal plasma

“…As in bull seminal plasma, citric acid is also found in semen of other species, such as boar [ 62 ], human [ 26 , 59 ], and rabbit [ 63 ]. Citric acid helps control pH in boar semen and acts as a chelator for zinc, magnesium, and calcium [ 62 ].…”

“…Both urea and phosphoric acid were detected in the seminal plasma samples of our study. Urea has also been found in human seminal fluid [ 20 , 26 , 67 ], however, the main role it plays in semen is still unknown. Given that urea is an end product of protein metabolism [ 68 ] and that seminal fluid contains protein, it is possible that seminal plasma urea is the consequence of protein degradation.…”

“…Metabolomics approaches have been also used to identify potential fertility biomarkers in the seminal plasma of bulls [ 11 ] and men [ 10 , 20 – 26 ]. Moreover, a recent study reported that gas chromatography-mass spectrometry (GC-MS) can be an innovative method for fast and noninvasive diagnostic of man infertility [ 27 ].…”

“…Analyses of human seminal plasma by Raman spectroscopy allowed the identification of metabolites associated with asthenozoospermic patients as well [ 21 ]. In another study, GC-MS of seminal fluid detected lower concentrations of palmitic acid and oleic acid in healthy men as compared to asthenozoospermic individuals [ 26 ]. These findings suggest that metabolomic analyses are valid tools for identification of many classes of molecules associated with metabolic pathways essential to reproductive success [ 10 , 12 ].…”

Uncovering sperm metabolome to discover biomarkers for bull fertility

“…In recent years, studies using approaches in metabolomics have revealed potential fertility biomarkers in the seminal plasma of humans [27, 28], stallions [12], and bulls [29]. In a recent publication, we reported the identification of 63 compounds in bull seminal plasma by using gas chromatography-mass spectroscopy (GC-MS).…”