Impact of hypoxia on male reproductive functions

Penile erection and cardiovascular function: effects and pathophysiology

Penile erection (PE) is a hemodynamic event that results from a neuroendocrine process, and it is influenced by the cardiovascular status of the patient. However, it may also modulate an individual's cardiovascular events. The present study provides the mechanisms involved in the association of PE and cardiovascular function. Erection upsurges the cardiac rate, blood pressure, and oxygen uptake. Sex-enhancing strategies, such as phosphodiesterase inhibitors, alprostadil, and testosterone also promote vasodilatation and cardiac performance, thus preventing myocardial infarction. More so, drugs that are used in the treatment of hypertensive heart diseases (such as angiotensin system inhibitors and β-blockers) facilitate vasodilatation and PE. These associations have been linked with nitric oxide- and testosterone-dependent enhancing effects on the vascular endothelium. In addition, impaired cardiovascular function may negatively impact PE; therefore, impaired PE may be a pointer to cardiovascular pathology. Hence, evaluation of the cardiovascular status of an individual with erectile dysfunction (ED) is essential. Also, employing strategies that are used in maintaining optimal cardiac function may be useful in the management of ED.

Anemia and testosterone deficiency risk: insights from NHANES data analysis and a Mendelian randomization analysis

BACKGROUND

Previous research has shown that testosterone deficiency (TD) increases the risk of anemia, but it is unclear whether anemia affects testosterone levels. This study investigated the influence of anemia on testosterone levels.

METHODS

Utilizing data from six NHANES cycles, including demographic, testosterone levels, and hemoglobin concentrations, we employed multivariable-adjusted logistic regression to investigate the relationship between anemia and testosterone levels. Moreover, a two-sample Mendelian randomization (MR) study employing genome-wide association study (GWAS) data examined the causal relationship. Kaplan-Meier survival estimation was used to compared the overall survival (OS) of anemic and nonanemic patients with low testosterone and normal testosterone levels.

RESULTS

The inclusion of 21,786 participants (2318 with anemia and19,468 without anemia) revealed that nonanemic patients exhibited higher testosterone levels than did anemic patients (β = 22.616, 95% CI: 3.873-41.359, p = 0.01807). MR analysis confirmed anemia as a cause of TD (OR = 1.045, 95% CI: 1.020-1.071, p < 0.001). Anemic males with low testosterone had reduced OS compared to those with normal levels (p < 0.001).

CONCLUSIONS

Anemia emerged as a potential risk factor for TD, highlighting a bidirectional relationship between these conditions. Additional prospective investigations are essential for the validation and reinforcement of our findings.

Acetate Abates Arsenic-Induced Male Reproductive Toxicity by Suppressing HDAC and Uric Acid-Driven Oxido-inflammatory NFkB/iNOS/NO Response in Rats

Arsenic is associated with male reproductive toxicity through histone deacetylation and oxido-inflammatory injury. Notwithstanding, short-chain fatty acids such as acetate exert anti-oxido-inflammatory activities and inhibit histone deacetylation. This study investigated the impact of acetate on arsenic-induced male reproductive toxicity. Forty eight adult male Wistar rats were allotted into any of these four groups (n = 12 rats per group): vehicle-treated, sodium acetate-treated, arsenic-exposed, and arsenic-exposed + sodium acetate-treated. The results revealed that arsenic exposure prolonged the latencies of mount, intromission, and ejaculation and reduced the frequencies of mount, intromission, and ejaculation, as well as mating and fertility indices, litter size and weight, anogenital distance, anogenital index, and survival rate in male F1 offspring at weaning. Also, arsenic reduced the circulating levels of gonadotropin-releasing hormone, luteinizing hormone, follicle-stimulating hormone, and testosterone and testicular 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase activities. In addition, arsenic reduced the daily and total spermatid production, sperm count, motility, and viability but increased the percentage of sperm cells with abnormal morphology. Furthermore, arsenic increased testicular xanthine oxidase activity, uric acid, and malondialdehyde levels, and reduced glutathione content, superoxide dismutase and catalase activities, total antioxidant capacity, and Nrf2 level. More so, arsenic exposure increased testicular iNOS activity and nitric oxide (NO), TNF-α, IL-1β, IL-6, and NFkB levels as well as Bax, caspase 9, and caspase 3 activities, and reduced Bcl-2. These findings were associated with arsenic-induced increase in testicular arsenic concentration, histone deacetylase activity, and reduced testicular weight. Histopathological examination revealed that arsenic also disrupted testicular histoarchitecture, which was accompanied by altered testicular planimetry and reduced spermatogenic cells. Notwithstanding, sodium acetate alleviated arsenic-induced sexual dysfunction as well as biochemical and histological alterations. These were accompanied acetate-driven downregulation of histone deacetylase (HDAC) activity. Succinctly, acetate attenuated arsenic-induced male reproductive toxicity by suppressing HDAC and uric acid-driven oxido-inflammatory NFkB/iNOS/NO response.

Inhibition of reactive oxygen species generation by N-Acetyl Cysteine can mitigate male germ cell toxicity induced by bisphenol analogs

The estrogen-like effect of bisphenol A (BPA) disrupting the maintenance of functional male germ cells is associated with male sub-fertility. This study investigated toxicity of male germ cells induced by four bisphenol analogs: BPA, BPAF, BPF, and BPS. The investigation of bisphenol analogs' impact on male germ cells included assessing proliferation, apoptosis induction, and the capacity to generate reactive oxygen species (ROS) in GC-1 spermatogonia (spg) cells, specifically type B spermatogonia. Additionally, the therapeutic potential and protective effects of N-Acetyl Cysteine (NAC) and NF-κB inhibitor parthenolide was evaluated. In comparison to BPA, BPF and BPS, BPAF exhibited the most pronounced adverse effect in GC-1 spg cell proliferation. This effect was characterized by pronounced inhibition of phosphorylation of PI3K, AKT, and mTOR, along with increased release of cytochrome c and subsequent cleavages of caspase 3, caspase 7, and poly (ADP-ribose) polymerase. Both NAC and parthenolide were effective reducing cellular ROS induced by BPAF. However, only NAC demonstrated a substantial recovery in proliferation, accompanied by a significant reduction in cytochrome c release and cleaved PARP. These results suggest that NAC supplementation may play an effective therapeutic role in countering germ cell toxicity induced by environmental pollutants with robust oxidative stress-generating capacity.

Hypobaric Hypoxia Causes Low Fecundity in Zebrafish Parents and Impairment of Skeletal Development in Zebrafish Embryos and Rat Offspring

Hypobaric Hypoxia (HH) negatively affects the cardiovascular and respiratory systems as well as gonadal development and the therefore next generation. This study investigated the effects of HH on zebrafish and SD rats, by exposing them to a low-pressure environment at 6,000m elevation for 30 days to simulate high-altitude conditions. It was indicated that parental zebrafish reared amh under HH had increased embryo mortality, reduced hatchability, and abnormal cartilage development in the offspring. Furthermore, the HH-exposed SD rats had fewer reproductive cells and smaller litters. Moreover, the transcriptome analysis revealed the down-regulation of steroid hormone biosynthesis pathways. The expression of the gonad-associated genes (amh, pde8a, man2a2 and lhcgr), as well as the gonad and cartilage-related gene bmpr1a, were also down-regulated. In addition, Western blot analysis validated reduced bmpr1a protein expression in the ovaries of HH-treated rats. In summary, these data indicate the negative impact of HH on reproductive organs and offspring development, emphasizing the need for further research and precautions to protect future generations' health.

Pathophysiology and management of testicular ischemia/reperfusion injury: Lessons from animal models

Testicular torsion is a urological emergency that involves the twisting of the spermatic cord along its course. Compelling pieces of evidence have implicated oxidative stress-sensitive signaling in pathogenesis of testicular I/R injury. Although, surgical detorsion is the mainstay management; blockade of the pathways involved in the pathogenesis may improve the surgical outcome. Experimental studies using various testicular I/R models have been reported in a bid to explore the mechanisms associated with testicular I/R and evaluate the benefits of potential therapeutic measures; however, most are limited by their shortcomings. Thus, this review was intended to describe the details of the available testicular I/R models as well as their merits and drawbacks, the pathophysiological basis and consequences of testicular I/R, and the pharmacological agents that have being proposed to confer testicular benefits against testicular I/R. This provides an understanding of the pathophysiological events and available models used in studying testicular I/R. In addition, this research provides evidence-based molecules with therapeutic potentials as well as their mechanisms of action in testicular I/R.

Hypoxia delays steroid-induced developmental maturation in Drosophila by suppressing EGF signaling

Animals often grow and develop in unpredictable environments where factors like food availability, temperature, and oxygen levels can fluctuate dramatically. To ensure proper sexual maturation into adulthood, juvenile animals need to adapt their growth and developmental rates to these fluctuating environmental conditions. Failure to do so can result in impaired maturation and incorrect body size. Here we describe a mechanism by which Drosophila larvae adapt their development in low oxygen (hypoxia). During normal development, larvae grow and increase in mass until they reach critical weight (CW), after which point a neuroendocrine circuit triggers the production of the steroid hormone ecdysone from the prothoracic gland (PG), which promotes maturation to the pupal stage. However, when raised in hypoxia (5% oxygen), larvae slow their growth and delay their maturation to the pupal stage. We find that, although hypoxia delays the attainment of CW, the maturation delay occurs mainly because of hypoxia acting late in development to suppress ecdysone production. This suppression operates through a distinct mechanism from nutrient deprivation, occurs independently of HIF-1 alpha and does not involve dilp8 or modulation of Ptth, the main neuropeptide that initiates ecdysone production in the PG. Instead, we find that hypoxia lowers the expression of the EGF ligand, spitz, and that the delay in maturation occurs due to reduced EGFR/ERK signaling in the PG. Our study sheds light on how animals can adjust their development rate in response to changing oxygen levels in their environment. Given that hypoxia is a feature of both normal physiology and many diseases, our findings have important implications for understanding how low oxygen levels may impact animal development in both normal and pathological situations.

Glutamine-mediated Modulation of XO/uric acid/NF-kB Signaling Pathway Ameliorates Intestinal I/R-induced Bacterial Translocation and Cardiorenal Inflammatory Injury

This study explored the effect of intestinal ischaemia/reperfusion (I/R) on cardiorenal tissues. The involvement of xanthine oxidase/uric acid/NF-kB signaling in intestinal I/R was also investigated. In addition, the possible protective effect of glutamine was also evaluated. Twenty-four male Wistar rats were acclimatized and then randomly assigned to four groups (n = 6); sham-operated, glutamine-treated rats (GLUT), I/R, and I/R + GLUT. The sham-operated rats were sham-operated and received 0.5 mL of distilled water, GLUT rats were sham-operated and had 1 g/kg b.w. of glutamine, I/R animals had an intestinal I/R procedure and received 0.5 mL of distilled water, and the I/R + GLUT rats had an intestinal I/R procedure and also received 1 g/kg b.w. of glutamine. Treatments were daily and per os. Glutamine attenuated intestinal I/R-induced rise in intestinal and cardiorenal activities of creatinine kinase and lactate dehydrogenase and lactate level. More so, glutamine alleviated I/R-induced rise in malondialdehyde, xanthine oxidase, uric acid, myeloperoxidase, NF-kB, TNF-α, IL-1β, caspase 3 activity, and DNA fragmentation. Furthermore, glutamine suppressed I/R-induced decline in GSH levels and SOD and catalase activities. Moreover, glutamine improved intestinal, cardiac, and renal histology in animals subjected to intestinal I/R.

Glutamine Alleviates I/R-Induced Intestinal Injury and Dysmotility Via the Downregulation of Xanthine Oxidase/Uric Acid Signaling and Lactate Generation in Wistar Rats

INTRODUCTION

Disruption of intestinal histoarchitecture and intestinal dysmotility is critical to intestinal ischemia/reperfusion (IR) injury and xanthine oxidase (XO)/uric acid (UA) signaling and increased lactate generation have been reported to play a role. More so, glutamine treatment has been demonstrated to inhibit XO/UA signaling. However, the role of glutamine in intestinal IR injury-induced intestinal dysmotility and the associated mechanisms of action are unclear. Therefore, this study was to investigate the mechanisms underlying the role of glutamine in intestinal IR injury.

METHODS

Forty male Wistar rats were acclimatized for two weeks and then randomized into four groups. The sham-operated, glutamine-treated, intestinal IR, and IR + glutamine groups.

RESULTS

Glutamine therapy attenuated the IR-induced increase in intestinal weight, disruption of intestinal histoarchitecture, and intestinal dysmotility. In addition, glutamine ameliorated IR-induced intestinal oxidative stress (increased malondialdehyde, reduced glutathione and superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, and glucose-6-phosphate dehydrogenase activities), inflammation (increased TNF-α and IL-1β), and apoptosis (increased caspase three activity). These events were accompanied by glutamine alleviation of IR-induced upregulation of intestinal nuclear factor kappa B, XO/UA, and lactate generation.

CONCLUSIONS

In conclusion, XO/UA signaling and lactate levels are key factors in IR-induced intestinal injury and dysmotility, and glutamine-mediated XO/UA/lactate modulation may attenuate IR-induced intestinal injury and dysmotility.

Sexual dysfunction in women with chronic obstructive lung disease

OBJECTIVE

To determine the prevalence of sexual dysfunction in women with COPD and the factors related to its presence.

METHODS

Cross-sectional observational study during 2021, including women with COPD diagnosed by spirometry through convenience sampling. Data on age, smoking status, spirometric data, comorbidities and medications used were collected. A sexual health questionnaire was administered.

RESULTS

The study included 101 women with a mean age of 59.7 (11.3) years. All had experienced a change in sexual activity, with 44% attributing it to COPD. Among them, 51.5% experienced dyspnea during coitus. The prevalence of sexual dysfunction was 52.5%. Women with sexual dysfunction were older and had a lower Tiffeneau index. Furthermore, they consumed alcohol more frequently and had hypertension and cerebrovascular disease, and less often, they had diabetes and heart failure. However, they scored lower on the Charlson index corrected for age. Patients with sexual dysfunction used inhaled triple therapy less frequently.

CONCLUSIONS

Sexual dysfunction is common in women with COPD. Further studies are needed to investigate its causes, mechanisms, and potential treatments.

Hypoxia, NSAIDs, and autism: A biocultural analysis of stressors in gametogenesis

Cultural and generational trends have increasingly favored "anti-inflammatory" action, innovating a new class of analgesic, non-steroidal anti-inflammatory drugs (NSAIDs) in the 20th century. The modern human body has been molded over evolutionary time and while acknowledging inflammation can be pathologically entwined, it also serves an important role in healthy folliculogenesis and ovulation, shaping cues that drive needed vascular change. This review argues that because of anti-inflammatory action, the cultural invention of NSAIDs represents a particular stressor on female reproductive-age bodies, interacting with natural, underlying variation and placing limits on healthy growth and development in the follicles, creating potential autism risk through hypoxia and mutagenic or epigenetic effects. Since testes are analogs to ovaries, the biological grounding extends naturally to spermatogenesis. This review suggests the introduction of over-the-counter NSAIDs in the 1980s failed to recognize the unique functioning of reproductive-age bodies, challenging the cyclical inflammation needed for healthy gamete development. NSAIDs are framed as one (notable) stressor in an anti-inflammatory era focused on taming the risks of inflammation in modern human life.

The Effects of Six-Gram D-Aspartic Acid Supplementation on the Testosterone, Cortisol, and Hematological Responses of Male Boxers Subjected to 11 Days of Nocturnal Exposure to Normobaric Hypoxia

The aim of this study was to evaluate the effects of D-aspartic acid (DAA) supplementation during a simulated altitude protocol on the hormonal and hematological responses in athletes. We hypothesized that DAA supplementation would contribute to an increase in the luteinizing hormone (LH), free, and testosterone and a greater increase in hematological variables. Sixteen male boxers participated; they were randomly assigned to an experimental group (DAA) or a control group (C) and underwent 14 days of supplementation, 6 g/day of DAA. Both DAA and C participants were exposed to normobaric hypoxia (FiO2 = 15.5%; 2500 m) for 10-12 h a day over a period of 11 days. The results showed that DAA had no significant effect on resting, LH, or the testosterone/cortisol ratio during the training camp. Hypoxic exposure significantly (p < 0.05) increased red blood cell and reticulocyte counts as well as hemoglobin and hematocrit concentrations in both groups, but DAA had no significant effect on these changes. In conclusion, we found that DAA supplementation at a dose of 6 g/day for 14 days does not affect the testosterone, cortisol, or hematological responses of athletes during.

Cascading effects of hypobaric hypoxia on the testis: insights from a single-cell RNA sequencing analysis

Most mammals tolerate exposure to hypobaric hypoxia poorly as it may affect multiple regulatory mechanisms and inhibit cell proliferation, promote apoptosis, limit tissue vascularization, and disrupt the acid-base equilibrium. Here, we quantified the functional state of germ cell development and demonstrated the interaction between the germ and somatic cells via single-cell RNA sequencing (scRNA-seq). The present study elucidated the regulatory effects of hypobaric hypoxia exposure on germ cell formation and sperm differentiation by applying enrichment analysis to genomic regions. Hypobaric hypoxia downregulates the genes controlling granule secretion and organic matter biosynthesis, upregulates tektin 1 (TEKT1) and kinesin family member 2C (KIF2C), and downregulates 60S ribosomal protein 11 (RPL11) and cilia- and flagella-associated protein 206 (CFAP206). Our research indicated that prosaposin-G protein-coupled receptor 37 (PSAP-GPR37) ligands mediate the damage to supporting cells caused by hypobaric hypoxic exposure. The present work revealed that hypoxia injures peritubular myoid (PTM) cells and spermatocytes in the S phase. It also showed that elongating spermatids promote maturation toward the G2 phase and increase their functional reserve for sperm-egg binding. The results of this study provide a theoretical basis for future investigations on prophylactic and therapeutic approaches toward protecting the reproductive system against the harmful effects of hypobaric hypoxic exposure.