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Here, we study possible mechanisms of (in/sub)fertility related to the acute or repeated psychological stresses (the most common stresses in human society) by following the transcriptional profile of 22 mitochondrial dynamics/function markers and 22 signaling molecules regulating both mitochondrial dynamics and spermatozoa number/functionality. An in vivo study mimicking acute (once for 3 h) and repeated (3 h for 10 consecutive days) psychophysical stress was performed on adult rats. The analysis of hormones, the number/functionality of spermatozoa, and 44 transcriptional markers were performed on individual samples from up to 12 animals per group. Results showed that both types of stress reduced spermatozoa functionality (acute by 4.4-fold, repeated by 3.3-fold) and ATP production (acute by 2.3-fold, repeated by 14.5-fold), while only repeated stress reduces the number of spermatozoa (1.9-fold). Stress significantly disturbed transcription of 34-out-of-44 markers (77%). Mitochondrial dynamics and functionality markers: 18-out-of-22 =&gt, 82% (mitochondrial-biogenesis-markers –&gt, 6-out-of-8 =&gt, 75%, mitochondrial-fusion-markers –&gt, 3-out-of-3 =&gt, 100%, mitochondrial-fission-markers –&gt, 1-out-of-2 =&gt, 50%, mitochondrial-autophagy-markers –&gt, mitochondrial-functionality-markers –&gt, 5-out-of-6 =&gt, 83%). Markers of signaling pathways regulating both mitochondrial dynamics/functionality and spermatozoa number/functionality important for male (in/sub)fertility –&gt, 16-out-of-22 =&gt, 73% (cAMP-signaling-markers –&gt, 8-out-of-12 =&gt, 67%, MAPK-signaling-markers –&gt, 8-out-of-10 =&gt, 80%). Accordingly, stress-triggered changes of transcriptional profile of mitochondrial dynamics/functionality markers as well as signaling molecules regulating both mitochondrial dynamics and spermatozoa number and functionality represent adaptive mechanisms.

Knowledge about the relationship between steroidogenesis and the regulation of the mitochondrial bioenergetics and dynamics, in steroidogenic cells, is not completely elucidated. Here we employed in vivo and ex vivo experimental models to analyze mitochondrial physiology in Leydig cells depending on the different LH-cAMP environments. Activation of LH-receptor in rat Leydig cells ex and in vivo triggered cAMP, increased oxygen consumption, mitoenergetic and steroidogenic activities. Increased mitoenergetic activity i.e., ATP production is achieved through augmented glycolytic ATP production and a small part of oxidative phosphorylation (OXPHOS). Transcription of major genes responsible for mitochondrial dynamics was upregulated for Ppargc1a (regulator of mitogenesis and function) and downregulated for Drp1 (main fission marker), Prkn, Pink1 and Tfeb (mitophagy markers). Leydig cells from gonadotropin-treated rats show increased mitogenesis confirmed by increased mitochondrial mass, increased mtDNA, more frequent mitochondria observed by a transmission electron microscope and increased expression of subunits of respiratory proteins Cytc/CYTC and COX4. Opposite, Leydig cells from hypogonadotropic-hypogonadal rats characterized by low LH-cAMP, testosterone, and ATP production, reduced markers of mitogenesis and mitofusion (Mfn1/2, Opa1) associated with reduced mtDNA content. Altogether results underline LH-cAMP signaling as an important regulator of mitochondrial physiology arranging mitochondrial dynamics, bioenergetic and steroidogenic function in Leydig cells.

Here we investigate the stress-signaling responsible for the effects of acute/repeated psychological stresses (the most common stresses in human society) on spermatozoa number and functionality, as well as the transcriptional profile of mitochondrial dynamics markers by using the in vivo and ex vivo approaches. Acute and repeated stress inhibit spermatozoa functionality (acute –> 3.2-fold, repeated –> 2.5-fold), while only repeated stress reduces the spermatozoa number (1.7-fold). Stress hormones mimic these effects and decrease the spermatozoa functionality (adrenaline: 10 µM –> 2.4-fold, 100 µM – > 2.8-fold; hydrocortisone: 50 pM –> 2.7-fold, 500 pM –> 8.5-fold). They also significantly disturb the transcriptional profile of all main mitochondrial dynamics markers in spermatozoa. Ex vivo manipulation of stress signaling in spermatozoa reveals that most of these effects are mediated through ɑ1-and/or-β-adrenergic receptors. The transcription of these receptors and their kinases in the same samples is under the significant influence of adrenergic signaling. Our results are the first to show the importance of mitochondrial dynamics markers in spermatozoa since the transcriptional profiles of sixteen-out-of-ninteen are disturbed by manipulation of stress-hormones-signaling. This is a completely new molecular approach to assess spermatozoa functionality and it is important for a better understanding of the correlations between stress, environmental-life-style and other factors, and male (in)fertility.

Aim A growing body of evidence pointed correlation between insulin-resistance, testosterone level and infertility, but there is scarce information about mechanisms. The aim of this study was to identify the possible mechanism linking the insulin-resistance with testosterone-producing-Leydig-cells functionality. Methods We applied in vivo and in vitro approaches. The in vivo model of functional genomics is represented by INSR/IGF1R-deficient-testosterone-producing Leydig cells obtained from the prepubertal (P21) and adult (P80) male mice with insulin + IGF1-receptors deletion in steroidogenic cells (Insr/Igf1r-DKO). The in vitro model of INSR/IGF1R-deficient-cell was mimicked by blockade of insulin/IGF1-receptors on the primary culture of P21 and P80 Leydig cells. Results Leydig-cell-specific-insulin-resistance induce the development of estrogenic characteristics of progenitor Leydig cells in prepubertal mice and mature Leydig cells in adult mice, followed with a dramatic reduction of androgen phenotype. Level of androgens in serum, testes and Leydig cells decrease as a consequence of the dramatic reduction of steroidogenic capacity and activity as well as all functional markers of Leydig cell. Oppositely, the markers for female-steroidogenic-cell differentiation and function increase. The physiological significances are the higher level of testosterone-to-estradiol-conversion in double-knock-out-mice of both ages and few spermatozoa in adults. Intriguingly, the transcription of pro-male sexual differentiation markers Sry/Sox9 increased in P21-Leydig-cells, questioning the current view about the antagonistic genetic programs underlying gonadal sex determination. Conclusion The results provide new molecular mechanisms leading to the development of the female phenotype in Leydig cells from Insr/Igf1r-DKO mice and could help to better understand the correlation between insulin resistance, testosterone and male (in)fertility.

OBJECTIVES/GOALS: The aim of this study was to define the transcription profiles of the molecular markers of mitochondrial biogenesis and fusion/architecture, and the markers of mtDNA copy numbers in the peripheral blood mononuclear cells (PBMCs) from war veterans with/without post-traumatic stress disorder (PTSD). METHODS/STUDY POPULATION: The peripheral blood mononuclear cells (PBMCs) from war veterans with/without post-traumatic stress disorder (PTSD) were used to monitor transcription profile of the molecular markers of mitochondrial biogenesis and fusion/architecture, as well as the markers of mtDNA copy numbers. The human male immortalized monocytes were exposed in vitro to hormonal markers of PTSD in order to monitor the effects of each particular hormonal marker on the molecular markers of mitochondrial biogenesis and fusion/architecture, as well as the markers of mtDNA copy numbers. RQ-PCR analyses were used to define transcriptional profile of above mentioned markers. RESULTS/ANTICIPATED RESULTS: The transcription profiles of above mentioned markers were disturbed, with high individual variability within the groups. A significant increase in the expression of the PPARGC1A transcript was observed in a group of subjects with current PTSD, as well as in the subjects with “life-time” PTSD, compared to healthy controls. PPARGC1B, NRF2 and MFN2 transcripts increased only in PBMCs of “life-time"-PTSD, while the level of transcripts for other investigated genes and the ratio of markers of mtDNA copy numbers showed no significant difference between groups. The in vitro results showed parallelism with the results obtained using the PBMCs from the subjects of the PTSD study. DISCUSSION/SIGNIFICANCE OF IMPACT: Although preliminary (the analysis require a larger number of subjects), the results are first findings and a solid base for further extensive multidisciplinary research in order to clarify the molecular mechanisms for the prevention and treatment of trauma-induced pathological conditions.

© The Author(s) 2018. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. Controlled changes in mitochondrial biogenesis and morphology are required for cell survival and homeostasis, but the molecular mechanisms are largely unknown. Here, male and female prepubertal mice (P21) with insulin and IGF1 receptors deletions in steroidogenic tissues (Insr/Igf1r-DKO) were used to investigate transcription of the key regulators of mitochondrial biogenesis (Ppargc1a, Ppargc1b, Pparg, Nrf1, Tfam) and architecture in Leydig cells, ovaries, and adrenals. Results showed that the expression of PGC1, a master regulator of mitochondrial biogenesis and integrator of environmental signals, and its downstream target Tfam, significantly decreased in androgen-producing Leydig cells. This is followed by reduction of Mtnd1, a mitochondrial DNA encoded transcript whose core subunit belongs to the minimal assembly required for catalysis. The same markers remained unchanged in ovaries. In contrast, in adrenals, the pattern of transcripts for mitochondrial biogenesis markers was the same in both sexes, but opposite from that observed in Leydig cells. The level of transcripts for markers of mitochondrial architecture (Mfn1, Mfn2) significantly increased in Leydig cells from Insr/Igf1r-DKO, but not in ovaries. This was followed by mitochondrial morphology disturbance, suggesting that the mitochondrial phase of steroidogenesis could be affected. Indeed, basal and pregnenolone stimulated progesterone productions in the mitochondria of Leydig cells from Insr/Igf1r-DKO decreased more than androgen production, and were barely detectable. Our results are the first to show that INSR/IGF1R are important for mitochondrial biogenesis in gonadal steroidogenic cells of prepubertal males, but not females and they serve as important regulators of mitochondrial architecture and biogenesis markers in Leydig cells.