The effects of the obesogen tributyltin on the metabolism of Sertoli cells cultured ex vivo

Abstract

Human exposure to environmental contaminants is widespread. Some of these contaminants have the ability to interfere with adipogenesis, being thus considered as obesogens. Recently, obesogens have been singled out as a cause of male infertility. Sertoli cells (SCs) are essential for male fertility and their metabolic performance, especially glucose metabolism, is under a tight endocrine control, being essential for the success of spermatogenesis. Herein, we studied the impact of the model obesogen tributyltin in the metabolic profile of SCs. For that, ex vivo-cultured rat SCs were exposed to increasing doses of tributyltin. SCs proliferation was evaluated by the sulforhodamine B assay and the maturation state of the cells was assessed by the expression of specific markers (inhibin B and the androgen receptor) by quantitative polymerase chain reaction. The metabolic profile of SCs was established by studying metabolites consumption/production by nuclear magnetic resonance spectroscopy and by analyzing the expression of key transporters and enzymes involved in glycolysis by Western blot. The proliferation of SCs was only affected in the cells exposed to the highest dose (1000 nM) of tributyltin. Notably, SCs exposed to 10 nM tributyltin decreased the consumption of glucose and pyruvate, as well as the production of lactate. The decreased lactate production hampers the development of germ cells. Intriguingly, the lowest levels of tributyltin were more prone to modulate the expression of key players of the glycolytic pathway. This is the first study showing that tributyltin reprograms glucose metabolism of SCs under ex vivo conditions, suggesting new targets and mechanisms through which obesogens modulate the metabolism of SCs and thus male (in)fertility.

Testosterone and Follicle Stimulating Hormone–Dependent Glyoxalase 1 Up-Regulation Sustains the Viability of Porcine Sertoli Cells through the Control of Hydroimidazolone– and Argpyrimidine-Mediated NF-κB Pathway

“…Indeed, the mechanism underpinning this effect is now also largely understood; SCs take up extracellular glucose and convert it into lactate, the preferred fuel of developing germ cells. 6,9,64 To fulfill this provisioning role, SCs produce high quantities of lactate through glycolysis 6 ; indeed, in their high glycolytic flux and lactate production, the metabolism of SCs is often compared with the "Warburg-like" 12,pp.127,128 metabolism observed in cancer cells. 11 However, this high glycolytic activity likely yields high quantities of MG as a toxic byproduct, especially under the influence of T/FSH exposure, placing even greater importance on protective mechanisms that mitigate the effects of MG-induced carbonyl stress.…”

“…7 In this ambit, SCs metabolic performance, especially glucose metabolism, which is under a tight endocrine control in these cells, is essential for the success of spermatogenesis and fertility. 9 In fact, a close metabolic cooperation between SCs and developing germ cells has long been postulated. In particular, developing germ cells are highly dependent on the lactate produced by SCs as metabolic fuel, 10,11 whereas high lactate production in SCs is in turn underpinned by their unusual carbohydrate metabolism; they present a high glycolytic flux where the majority of glucose is converted into lactate and not oxidized via the citric acid cycle.…”

Metabolic diseases affect male reproduction and induce signatures in gametes that may compromise the offspring health

“…The exposure to some organochlorines is associated with decreased sperm counts ( 84 ), while aromatic hydrocarbons, another class of toxins, are reportedly described as major contributors for the dysfunction of sperm parameters ( 85 ). Although the presence of liposoluble toxins in the testis is likely one of the ways by which obesity induces infertility in males, this topic has been overlooked over the years ( 86 ).…”

Assessment of Sertoli Cell Proliferation by 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐Diphenyltetrazolium Bromide and Sulforhodamine B Assays

“…The application of these protocols using SCs is just a first step in determining the toxicity of a compound. SRB assays are widely used to assess toxicity in primary cultures of rat (Cardoso et al., ) and human SCs (Dias et al., ; Jesus et al., ). MTT assays are widely used to assess cytotoxicity in mouse SCs lines (Ge et al., ; Hu et al., ; Pourhassanali et al., ), primary cultures of mouse (Hu et al., ), rat (Yang, Han, Wei, Chen, & Yin, ), and piglet (Zhang et al., ) SCs.…”

“…Experiments with SCs can be performed using immortalized cell lines or cells from primary cultures of SCs derived from human (Bernardino et al, 2019;Martins et al, 2015Martins et al, , 2016Martins et al, , 2019, rat (Cardoso et al, 2018), mouse (Bernardino, Carrageta, et al, 2018), or other animals (Adegoke et al, 2018;Dance, Kastelic, & Thundathil, 2017). The assessment of SC proliferation using MTT (Basic Protocol 1) and SRB (Basic Protocol 2) can be performed in any type of SC, whether obtained from primary (independent of the origin) or immortalized cultures.…”