Differences in the sperm metabolomes of smoking and nonsmoking men

Abstract

Currently, spermiogram analysis is the most relevant method used to clarify the potential infertility of a couple. However, in some cases, the reasons for infertility remain obscure. Smoking is among the factors that have been described to adversely affect male fertility. Smoking increases oxidative stress and thus promotes various pathological processes. Comparative studies, particularly those on metabolomic changes in sperm and seminal plasma caused by smoking, have not yet been published. Thus, the present pilot study aimed at the mass spectrometric characterization of the metabolomes of specimens from both smoking and nonsmoking subjects and the comparison of the evaluated data in terms of sperm apoptosis and spermiogram parameters. The results provided evidence that the conventional spermiogram is not altered in smokers compared to nonsmokers. However, a more careful investigation of sperm cells by metabolomic profiling reveals profound effects of smoking on sperm: first, nitrogen oxide synthase, a marker of oxidative stress, is activated. Second, the uptake of fatty acids into sperm mitochondria is reduced, leading to an impaired energy supply. Third, phenylalanine hydroxylation and tryptophan degradation, which are both indications of altered tetrahydrobiopterin biosynthesis, are reduced. Moreover, flow cytometry approaches indicated increased sperm caspase-3 activity, a sign of apoptosis. The present study clearly shows the negative effects of smoking on semen quality. Especially for idiopathic cases, metabolomic profiling can help to shed light on male sub- or infertility.

Semen parameters after SARS‐CoV‐2 infection: A literature review

“… 9 Two of these three patients presented with two semen analyses before SARS‐CoV‐2 infection but with no exact date of sample collection. With the knowledge that events and lifestyle changes could affect semen quality, 18 , 19 , 20 , 21 it was assumed that the most accurate to compare with, was the most recent one. 9 …”

“…Smoking could affect semen quality 18 and should be taken into account as a likely confounder. Only one study considered smoking as an exclusion criterion, 15 but it still found a significant increase in semen parameters when comparing samples collected during the acute phase of the illness to samples collected over three months after the infection.…”

“…9 Two of these three patients presented with two semen analyses before SARS-CoV-2 infection but with no exact date of sample collection. With the knowledge that events and lifestyle changes could affect semen quality, [18][19][20][21] it was assumed that the most accurate to compare with, was the most recent one. 9 In three articles, [10][11][12] the number of participants was between 21 and 29, while in the article by Erbay et al, 13 there were 69 patients, divided into 26 with mild symptoms and 43 with moderate symptoms.…”

Metabolomics of Human Semen: A Review of Different Analytical Methods to Unravel Biomarkers for Male Fertility Disorders

“…Just recently, we published a small study on the influence of smoking on caspase activity and on the levels of defined metabolites in mature sperm cells and SP using LC-MS [ 55 ]. As a study population, we recruited ten smoking and ten nonsmoking normozoospermic men.…”

Editorial: Intra- and extra-environment and reproduction

“…Pesticide residues are deleterious to ovarian function and oocytes (Biggs et al, 2008;Liu et al, 2021). Lifestyle factors such as smoking also contribute to infertility, (Esakky and Moley, 2016;Engel et al, 2021).…”