Bio-effect monitoring using a [(15)N]methacetin test as diagnostic tool to monitor remediation effects in an industrially polluted region

Differences in the sperm metabolomes of smoking and nonsmoking men†

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 subfertility or infertility.

Metabolomics reveals effects of maternal smoking on endogenous metabolites from lipid metabolism in cord blood of newborns

INTRODUCTION

A general detrimental effect of smoking during pregnancy on the health of newborn children is well-documented, but the detailed mechanisms remain elusive.

OBJECTIVES

Beside the specific influence of environmental tobacco smoke derived toxicants on developmental regulation the impact on the metabolism of newborn children is of particular interest, first as a general marker of foetal development and second due to its potential predictive value for the later occurrence of metabolic diseases.

METHODS

Tobacco smoke exposure information from a questionnaire was confirmed by measuring the smoking related metabolites S-Phenyl mercapturic acid, S-Benzyl mercapturic acid and cotinine in maternal urine by LC-MS/MS. The impact of smoking on maternal endogenous serum metabolome and children's cord blood metabolome was assessed in a targeted analysis of 163 metabolites by an LC-MS/MS based assay. The anti-oxidative status of maternal serum samples was analysed by chemoluminiscence based method.

RESULTS

Here we present for the first time results of a metabolomic assessment of the cordblood of 40 children and their mothers. Several analytes from the group of phosphatidylcholines, namely PCaaC28:1, PCaaC32:3, PCaeC30:1, PCaeC32:2, PCaeC40:1, and sphingomyelin SM C26:0, differed significantly in mothers and children's sera depending on smoking status. In serum of smoking mothers the antioxidative capacity of water soluble compounds was not significantly changed while there was a significant decrease in the lipid fraction.

CONCLUSION

Our data give evidence that smoking during pregnancy alters both the maternal and children's metabolome. Whether the different pattern found in adults compared to newborn children could be related to different disease outcomes should be in the focus of future studies.