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.

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.

Metabolic Derangement by Arsenic: a Review of the Mechanisms

Studies have implicated arsenic exposure in various pathological conditions, including metabolic disorders, which have become a global phenomenon, affecting developed, developing, and under-developed nations. Despite the huge risks associated with arsenic exposure, humans remain constantly exposed to it, especially through the consumption of contaminated water and food. This present study provides an in-depth insight into the mechanistic pathways involved in the metabolic derangement by arsenic. Compelling pieces of evidence demonstrate that arsenic induces metabolic disorders via multiple pathways. Apart from the initiation of oxidative stress and inflammation, arsenic prevents the phosphorylation of Akt at Ser473 and Thr308, leading to the inhibition of PDK-1/Akt insulin signaling, thereby reducing GLUT4 translocation through the activation of Nrf2. Also, arsenic downregulates mitochondrial deacetylase Sirt3, decreasing the ability of its associated transcription factor, FOXO3a, to bind to the agents that support the genes for manganese superoxide dismutase and PPARg co-activator (PGC)-1a. In addition, arsenic activates MAPKs, modulates p53/ Bcl-2 signaling, suppresses Mdm-2 and PARP, activates NLRP3 inflammasome and caspase-mediated apoptosis, and induces ER stress, and ox-mtDNA-dependent mitophagy and autophagy. More so, arsenic alters lipid metabolism by decreasing the presence of 3-hydroxy-e-methylglutaryl-CoA synthase 1 and carnitine O-octanoyl transferase (Crot) and increasing the presence of fatty acid-binding protein-3 mRNA. Furthermore, arsenic promotes atherosclerosis by inducing endothelial damage. This cascade of pathophysiological events promotes metabolic derangement. Although the pieces of evidence provided by this study are convincing, future studies evaluating the involvement of other likely mechanisms are important. Also, epidemiological studies might be necessary for the translation of most of the findings in animal models to humans.

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.

Gut microbiota-gonadal axis: the impact of gut microbiota on reproductive functions

The influence of gut microbiota on physiological processes is rapidly gaining attention globally. Despite being under-studied, there are available data demonstrating a gut microbiota-gonadal cross-talk, and the importance of this axis in reproduction. This study reviews the impacts of gut microbiota on reproduction. In addition, the possible mechanisms by which gut microbiota modulates male and female reproduction are presented. Databases, including Embase, Google scholar, Pubmed/Medline, Scopus, and Web of Science, were explored using relevant key words. Findings showed that gut microbiota promotes gonadal functions by modulating the circulating levels of steroid sex hormones, insulin sensitivity, immune system, and gonadal microbiota. Gut microbiota also alters ROS generation and the activation of cytokine accumulation. In conclusion, available data demonstrate the existence of a gut microbiota-gonadal axis, and role of this axis on gonadal functions. However, majority of the data were compelling evidences from animal studies with a great dearth of human data. Therefore, human studies validating the reports of experimental studies using animal models are important.

Sodium acetate abates lead-induced sexual dysfunction by upregulating testosterone-dependent eNOS/NO/cGMP signaling and activating Nrf2/HO-1 in male Wistar rat

Oxidative stress has been linked with lead toxicity, including lead-induced sexual dysfunction. On the contrary, sodium acetate has been proven to exert antioxidant activity. However, the effect of sodium acetate on lead-induced sexual dysfunction has not been fully explored. This study investigated the effect of sodium acetate on lead-induced sexual dysfunction, exploring the involvement of testosterone, eNOS/NO/cGMP, and Nrf2/HO-1 signaling. Twenty male Wistar rats with similar weights were randomly assigned into four groups (n = 5 rats/group) after two weeks of acclimatization. Animals were vehicle-treated (0.5 ml/day of distilled water, per os), acetate-treated (200 mg/kg/day, per os), lead-treated (20 mg/kg/day, per os), or lead + acetate-treated. The results revealed that sodium acetate treatment attenuated lead-induced rise in penile lead, malondialdehyde and oxidized glutathione concentrations, and acetylcholinesterase activity. In addition, lead exposure prolonged mount, intromission, and ejaculation latency and reduced mount, intromission, and ejaculation frequency, as well as the motivation to mate and penile reflex, which were improved by acetate treatment. More so, acetate treatment ameliorated lead-induced reductions in absolute and relative penile weight, eNOS, NO, cGMP, luteinizing hormone, follicle-stimulating hormone, testosterone, dopamine, Nrf2, HO-1, and reduced glutathione concentrations, as well as glutathione reductase, glutathione peroxidase, glutathione-S-transferase, superoxide dismutase, and catalase activities. In conclusion, this study demonstrates that sodium acetate attenuated lead-induced sexual dysfunction by upregulating testosterone-dependent eNOS/NO/cGMP and Nrf2/HO-1 signaling. Despite the compelling data presented in this study, other possible associated mechanisms in the protective role of acetate should be explored.

Sodium acetate ameliorates doxorubicin-induced cardiac injury via upregulation of Nrf2/HO-1 signaling and downregulation of NFkB-mediated apoptotic signaling in Wistar rats

Despite the effectiveness of doxorubicin (DOX) in the management of a wide range of cancers, a major challenge is its cardio-toxic effect. Oxidative stress, inflammation, and apoptosis are major pathways for the cardiotoxic effect of DOX. On the other hand, acetate reportedly exerts antioxidant, anti-inflammatory, and anti-apoptotic activities. This particular research assessed the impact of acetate on cardiotoxicity induced by DOX. Mechanistically, acetate dramatically inhibited DOX-induced upregulation of xanthine oxidase and uric acid pathway as well as downregulation of Nrf2/HO-1 signaling and its upstream proteins (reduced glutathione peroxidase, superoxide dismutase, glutathione-S-transferase, glutathione, and catalase, glutathione reductase). In addition, acetate markedly attenuated DOX-driven rise inTNF-α, NFkB IL-6 and IL-1β expression, and myeloperoxidase activity. Furthermore, acetate significantly ameliorated DOX-led suppression of Bcl-2 and Ca2+-ATPase activity and upregulation of Bax, caspase 3, and caspase 9 actions. Improved body weight, heart structural integrity, and cardiac function as depicted by cardiac injury markers convoyed these cascades of events. Summarily, the present study demonstrated that acetate protects against DOX-induced cardiotoxicity by upregulating Nrf2/HO-1 signaling and downregulating NFkB-mediated activation of Bax/Bcl-2 and caspase signaling.

Acetate attenuates cyclophosphamide-induced cardiac injury via inhibition of NF-kB signaling and suppression of caspase 3-dependent apoptosis in Wistar rats

AIM

The goal of the current study was to examine the potential therapeutic effects of sodium acetate on cardiac toxicities caused by cyclophosphamide in Wistar rats. The possible involvement of NF-kB/caspase 3 signaling was also explored.

MAIN METHODS

Thirty-two male Wistar rats were divided into four groups at random. (n = 8). The control animals received 0.5 mL of distilled water orally for 14 days, the acetate-treated group received 200 mg/kg/day of sodium acetate orally for 14 consecutive days, and cyclophosphamide-treated rats received 150 mg/kg /day of cyclophosphamide i.p. on day 8, while cyclophosphamide + acetate group received sodium acetate and cyclophosphamide as earlier stated.

KEY FINDINGS

Results showed that cyclophosphamide-induced cardiotoxicity, which manifested as a marked drop in body and cardiac weights as well as cardiac weight/tibial length, increased levels of troponin, C-reactive protein, lactate, and creatinine kinase, and lactate dehydrogenase activities in the plasma and cardiac tissue. Histopathological examination also revealed toxic cardiac histopathological changes. These alterations were associated with a significant increase in xanthine oxidase and myeloperoxidase activities, uric acid, malondialdehyde, TNF-α, IL-1β, NFkB, DNA fragmentation, and caspase 3 and caspase 9 activities in addition to a marked decline in Nrf2 and GSH levels, and SOD and catalase activities in the cardiac tissue. Acetate co-administration significantly attenuated cyclophosphamide cardiotoxicity by its antioxidant effect, preventing NFkB activation and caspase 9/caspase 3 signalings.

SIGNIFICANCE

This study shows that acetate co-administration may have cardio-protective effects against cyclophosphamide-induced cardiotoxicity by inhibiting NF-kB signaling and suppressing caspase-3-dependent apoptosis.

Zinc improves sexual performance and erectile function by preventing penile oxidative injury and upregulating circulating testosterone in lead-exposed rats

AIM

The present study evaluated the effect of lead exposure with and without zinc therapy on male sexual and erectile function.

METHODS

Twenty male Wistar rats were randomly assigned into four groups; the control, zinc-treated, lead-exposed, lead + zinc-treated groups. Administrations were per os daily for 28 days.

RESULTS

Zinc co-administration significantly improved absolute and relative penile weights and the latencies and frequencies of mount, intromission, and ejaculation in lead-exposed rats. Also, zinc ameliorated lead-induced reductions in motivation to mate and penile reflex/erection. These findings were accompanied by attenuation of lead-induced suppression of circulating nitric oxide (NO), penile cyclic guanosine monophosphate (cGMP), dopamine, serum luteinizing hormone, follicle-stimulating hormone, and testosterone. In addition, zinc alleviated lead-induced upregulation of penile activities of acetylcholinesterase and xanthine oxidase (XO), and uric acid (UA) and malondialdehyde (MDA) levels. Furthermore, zinc ameliorated the lead-induced decline in penile nuclear factor erythroid 2-related factor 2 (Nrf2) and reduced glutathione (GSH) levels, and catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) activities.

CONCLUSION

This study revealed that co-administration of zinc improves lead-induced sexual and erectile dysfunction by suppressing XO/UA-driven oxidative stress and upregulating testosterone via Nrf2-mediated signaling.

Zinc protects against lead-induced testicular damage via modulation of steroidogenic and xanthine oxidase/uric acid/caspase 3-mediated apoptotic signaling in male Wistar rats

AIM

This study evaluated the effect of lead, with or without zinc co-administration, on steroidogenic and xanthine oxidase (XO)/uric acid (UA)/caspase 3-mediated apoptotic signaling in the testis.

MATERIALS AND METHODS

Forty male Wistar rats were divided into four groups at random; vehicle-treated control, zinc-treated, lead-treated, and lead + zinc-treated groups.

RESULTS

Lead exposure significantly lowered overall weight gain, testicular, epididymal, seminal vesicle, and prostate weights. Also, lead decreased sperm count, viability and motility but increased the fraction of sperm with aberrant morphology. In addition, lead caused a marked rise in the level of UA and XO activity but a decrease in nuclear factor erythroid 2-related factor 2 (Nrf2), reduced glutathione (GSH) as well as total antioxidant capacity (TAC) levels, and superoxide dismutase (SOD) and catalase activities. Furthermore, lead increased the testicular levels of nuclear factor kappa B (NFkB), interleukin-1beta (IL-1β), and tumour necrotic factor-alpha (TNF-α), which were associated with an increase in testicular caspase 3 activity and DNA fragmentation as well as a decline in circulating gonadotropin releasing hormone (GnRH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, and testicular 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD). These were associated with lead-induced degenerative changes in testicular tissues evidenced by shrunken seminiferous tubules, degeneration and sloughing of germ cells. Co-administration of zinc prevented lead-induced testicular injury by ameliorating oxidative stress, apoptosis, and inflammation through downregulation of XO/UA/caspase 3 pathway and upregulation of testicular 3β-HSD/17β-HSD.

CONCLUSION

This study demonstrated that zinc protected against lead-induced testicular toxicity via the downregulation of XO/UA/caspase 3 signaling.

Zinc improves sexual and erectile function in HAART-treated rats via the upregulation of erectogenic enzymes and maintenance of redox balance

PURPOSE

HAART has been shown to impair sexual function and penile erection via perturbation of penile redox balance, while zinc has been established to exert antioxidant activity. Therefore, this study focused on the role and associated molecular mechanism of zinc in HAART-induced sexual and erectile dysfunction.

MATERIALS AND METHODS

Twenty male Wistar rats were randomly grouped into four (n = 5 rats per group); the control, zinc-treated, HAART-treated, and HAART + zinc-treated groups. Treatments were per os daily for eight weeks.

RESULTS

Zinc co-administration significantly improved HAART-induced increase in the latencies of mount, intromission, and ejaculations. Zinc also attenuated HAART-induced reduction in the motivation to mate, penile reflex/erection, and frequencies of mount, intromission, and ejaculations. In addition, zinc co-treatment improved HAART-induced decline in penile NO and cGMP, dopamine, and serum testosterone. More so, zinc prevented HAART-induced rise in penile activities of monoamine oxidase, acetylcholinesterase, phosphodiesterase-5, and arginase. Furthermore, concomitant treatment with zinc ameliorated HAART-induced penile oxidative stress and inflammation.

CONCLUSION

In conclusion, our present findings show that zinc improves sexual and erectile function in HAART-treated rats by upregulating erectogenic enzymes via the maintenance of penile redox balance.

Histopathological evaluation of infertility: Lessons from laboratory rodents

Infertility is a growing challenge globally with emerging risk factors. There are effective laboratory tests to evaluate infertility in humans, nevertheless, some measures, especially histopathological evaluations, are invasive due to the pain inflicted when accessing the reproductive organs and obtaining samples; hence, their relevance may be limited in humans. However, these histopathological evaluations provide essential information on the etiopathogenesis of infertility and the likely mechanisms of action of potential therapeutic candidates. Also, non-invasive methods are available, such as the assay of testosterone in the blood and semen analysis, both of which are predictors of testicular functions. This review provides detailed information on the available histopathological investigations of infertility, such as qualitative and quantitative histopathological assessments of gonadal tissues, specific cell counts, and sperm morphology characterization, with a focus on the procedures, interpretation, and pathophysiological basis. Data from the literature revealed that histopathological examinations of the reproductive organs, as well as spermatozoa, are useful in understanding the pathogenesis of incident infertility. Histopathological evaluation may range from basic hematoxylin and eosin stains to some special stains. Also, histopathological findings (such as spermatogenic cells and planimetric variables, like seminiferous tubule diameter and theca cell and corpus luteum thickness) may be quantified and analyzed for comparison. Some skill is required for these investigations, which may be a limiting factor; however, they are important tools in translational medicine.

Psychoactive drugs and male fertility: impacts and mechanisms

Although psychoactive drugs have their therapeutic values, they have been implicated in the pathogenesis of male infertility. This study highlights psychoactive drugs reported to impair male fertility, their impacts, and associated mechanisms. Published data from scholarly peer-reviewed journals were used for the present study. Papers were assessed through AJOL, DOAJ, Google Scholar, PubMed/PubMed Central, and Scopus using Medical Subjects Heading (MeSH) indexes and relevant keywords. Psychoactive drugs negatively affect male reproductive functions, including sexual urge, androgen synthesis, spermatogenesis, and sperm quality. These drugs directly induce testicular toxicity by promoting ROS-dependent testicular and sperm oxidative damage, inflammation, and apoptosis, and they also suppress the hypothalamic-pituitary-testicular axis. This results in the suppression of circulating androgen, impaired spermatogenesis, and reduced sperm quality. In conclusion, psychoactive drug abuse not only harms male sexual and erectile function as well as testicular functions, viz., testosterone concentration, spermatogenesis, and sperm quality, but it also alters testicular histoarchitecture through a cascade of events via multiple pathways. Therefore, offering adequate and effective measures against psychoactive drug-induced male infertility remains pertinent.

L-Arginine abrogates maternal and pre-pubertal codeine exposure-induced impaired spermatogenesis and sperm quality by modulating the levels of mRNA encoding spermatogenic genes

Introduction

Although, codeine has been demonstrated to lower sperm quality; the effects of maternal and prepubertal codeine exposure on male offspring is yet to be reported. In addition, the effect of arginine on codeine-induced decline in sperm quality has not been explored. This study investigated the impact of maternal and prepubertal codeine exposure on spermatogenesis and sperm quality in F1 male Wistar rats to study the effect that codeine may have during recreational use in humans. Also, the effect of arginine supplementation on codeine-induced alteration in spermatogenesis and sperm quality was evaluated.

Methods

Female rats were treated with either 0.5 ml distilled water or codeine orally for eight weeks, and then mated with male rats (female:male, 2:1). The F1 male offsprings of both cohorts were weaned at 3 weeks old and administered distilled water, codeine, arginine, or codeine with arginine orally for eight weeks.

Results

Prepubertal codeine exposure in rats whose dams (female parents) were exposed to codeine delayed puberty and reduced the weight at puberty. Prepubertal codeine exposure exacerbated maternal codeine exposure-induced reduced total and daily spermatid production, sperm count, sperm motility, and normal sperm form, as well as impaired sperm plasma membrane integrity and increased not intact acrosome and damaged sperm DNA integrity. These perturbations were accompanied by a decrease in mRNA levels encoding spermatogenic genes, testicular testosterone and androgen receptor (AR) concentrations, and upregulation of sperm 8-hydroxydeoxyguanosine (8OHdG). Prepubertal arginine supplementation mitigated codeine-induced alterations.

Discussion

This study provides novel experimental evidence that maternal and prepubertal codeine exposure reprogramed spermatogenesis and sperm quality of male FI generation by decreasing mRNA levels encoding spermatogenic genes and AR via oxidative stress-mediated signaling, which was abrogated by prepubertal arginine supplementation.

Progress in research on the reproductive function in the sand rat (Psammomys obesus): A review

The Fat Sand Rat (Psammomys obesus, P. obesus) is a diurnal herbivore and phytophage, with seasonal reproductive behavior. The sexually active phase lasts from autumn to early spring and the sexually inactive phase from late spring to summer. In the past years, P. obesus has gained much attention as an animal model in biological and clinical research. It is a suitable model for diet-induced insulin resistance, non-insulin-dependent diabetes mellitus and obesity studies. In addition, the seasonal reproduction of P. obesus is gaining more and more attention. The current paper aims to review and sum up the progress in the understanding of the reproductive anatomo-histo-physiology of Psammomys obesus, in order to facilitate future research in this area and to expose further perspectives for researchers.

Atorvastatin-mediated downregulation of VCAM-1 and XO/UA/caspase 3 signaling averts oxidative damage and apoptosis induced by ovarian ischaemia/reperfusion injury

Background

Oxidative damage is critical in the pathogenesis of ovarian ischaemia/reperfusion (I/R) injury, and statins have been reported to exert antioxidant activity. However, the role of VCAM-1 and xanthine oxidase (XO)/uric acid (UA) in ovarian I/R injury is not known. Also, whether or not atorvastatin exerts antioxidant activity like other statins is unclear.

Objectives

This study investigated the involvement of VCAM-1 and XO/UA in ovarian I/R injury and the likely protective role of atorvastatin.

Methods

Forty female Wistar rats were randomized into sham-operated, ischaemia, ischaemia/reperfusion (I/R), ischaemia and atorvastatin, and I/R and atorvastatin.

Results

In comparison with the sham-operated group, atorvastatin blunted ischaemia and I/R-induced distortion of ovarian histoarchitecture and follicular degeneration. Also, atorvastatin alleviated ischaemia and I/R-induced rise in XO, UA, and malondialdehyde, which was accompanied by inhibition of ischaemia and I/R-induced reductions in reduced glutathione level, enzymatic antioxidant activities and increase in myeloperoxidase activity and TNF-α and IL-6 levels by atorvastatin treatment. Additionally, atorvastatin blocked ischaemia and I/R-induced increase in VCAM-1 expression, caspase 3 activity, 8-hydroxydeoxyguanosine level and ovarian DNA fragmentation index.

Conclusion

For the first time, this study revealed that atorvastatin-mediated downregulation of VCAM-1 and XO/UA/caspase 3 signaling averts oxidative injury, inflammation, and apoptosis induced by ovarian ischaemia/reperfusion injury.

Impact of COVID 19 on erectile function

Purpose: COVID-19, a novel infection, presented with several complications, including socioeconomical and reproductive health challenges such as erectile dysfunction (ED). The present review summarizes the available shreds of evidence on the impact of COVID-19 on ED.Materials and methods: All published peer-reviewed articles from the onset of the COVID-19 outbreak to date, relating to ED, were reviewed. Results: Available pieces of evidence that ED is a consequence of COVID-19 are convincing. COVID-19 and ED share common risk factors such as disruption of vascular integrity, cardiovascular disease (CVD), cytokine storm, diabetes, obesity, and chronic kidney disease (CKD). COVID-19 also induces impaired pulmonary haemodynamics, increased ang II, testicular damage and low serum testosterone, and reduced arginine-dependent NO bioavailability that promotes reactive oxygen species (ROS) generation and endothelial dysfunction, resulting in ED. In addition, COVID-19 triggers psychological/mental stress and suppresses testosterone-dependent dopamine concentration, which contributes to incident ED.Conclusions: In conclusion, COVID-19 exerts a detrimental effect on male reproductive function, including erectile function. This involves a cascade of events from multiple pathways. As the pandemic dwindles, identifying the long-term effects of COVID-19-induced ED, and proffering adequate and effective measures in militating against COVID-19-induced ED remains pertinent.

Impact of hypoxia on male reproductive functions

Male reproductive functions, which include testicular steroidogenesis, spermatogenesis, and sexual/erectile functions are key in male fertility, but may be adversely altered by several factors, including hypoxia. This review demonstrates the impact of hypoxia on male reproductive functions. Acute exposure to hypoxia promotes testosterone production via stimulation of autophagy and upregulation of steroidogenic enzymes and voltage-gated L-type calcium channel, nonetheless, chronic exposure to hypoxia impairs steroidogenesis via suppression of the hypothalamic-pituitary-testicular axis. Also, hypoxia distorts spermatogenesis and reduces sperm count, motility, and normal forms via upregulation of VEGF and oxidative stress-sensitive signaling. Furthermore, hypoxia induces sexual and erectile dysfunction via a testosterone-dependent downregulation of NO/cGMP signaling and upregulation of PGE1/TGFβ1-driven penile endothelial dysfunction. Notably, hypoxia programs male sexual function and spermatogenesis/sperm quality via feminization and demasculinization of males and oxidative stress-mediated alteration in sperm DNA methylation. Since oxidative stress plays a central role in hypoxia-induced male reproductive dysfunction, studies exploring the effects of antioxidants and upregulation of transcription of antioxidants on hypoxia-induced male reproductive dysfunction are recommended.

Glutamine prevents upregulation of NF-kB signaling and caspase 3 activation in ischaemia/reperfusion-induced testicular damage: An animal model

AIM

Testicular ischaemia/reperfusion (I/R) injury is a major consequence of testicular torsion with possible attendant risk of male infertility. Glutamine, on the other hand, is a known antioxidant with anti-inflammatory potential. The present study evaluated whether or not glutamine would improve I/R-induced testicular injury in torsion/detorsion (T/D). The possible associated mechanisms were also investigated.

METHODS

Wistar rats were randomly allotted into four groups (n = 10); sham-operated, glutamine-treated, T/D, and T/D + glutamine. Testicular torsion was induced and reperfusion established after two and a half hour under ketamine/xylazine anaethesia. Glutamine was administered one hour before reperfusion and continued daily for 3 days. At the end of the study, animals were euthanized, blood samples obtained, epididymal sperm suspension collected, and the testes harvested for biochemical and histopathological assays using established methods.

RESULTS

Glutamine prevented T/D-driven I/R-induced reduced sperm quality, impaired testicular histoarchitecture, and suppressed circulating testosterone. Also, glutamine abated I/R-induced oxidative stress (evidenced by reduced hydrogen peroxide and MDA generation and enhanced concentrations and activities of antioxidants), inflammation (evidenced by suppression of TNF-α and IL-1β), and apoptosis (evidenced by reduced DNA fragmentation) by down-regulating NF-kB and caspase 3 activity.

CONCLUSION

For the first time, this study demonstrated that glutamine administration improved testicular I/R injury in T/D rat model by maintaining testicular redox balance, and testicular integrity and function via inhibition of I/R-induced upregulation of NF-kB signaling and caspase 3 activation.

Suppression of glutathione system and upregulation of caspase 3-dependent apoptosis mediate rohypnol-induced gastric injury

Objectives: This study investigated the impact of rohypnol on gastric tissue integrity.

Methods: Forty male Wistar rats were randomized into control, low dose rohypnol-treated, high dose rohypnol-treated, low dose rohypnol-treated recovery and high dose rohypnol-treated recovery groups.

Results: Rohypnol caused significant rise in gastric malondialdehyde (MDA), oxidized glutathione (GSSG), nitric oxide (NO), tumour necrotic factor-α (TNF-α), and interleukin-6 (IL-6) levels. Also, rohypnol caused reductions in gastric reduced glutathione (GSH) (as well as GSH/GSSG), and activities of superoxide dismutase (SOD), catalase, glutathione-S-transferase (GST), glutathione peroxidase (GPx), cyclo-oxygenase (COX-2). Furthermore, rohypnol upregulated caspase 3 activity and induced gastric DNA damage, evident by a rise in 8-hydroxydeoxyguanosine (8-OHdG) and DNA fragmentation index (DFI) in gastric tissue. These alterations were coupled with reduced gastric weight and distorted gastric cytoarchitecture. Cessation of rohypnol caused a significant but not complete reversal of rohypnol-induced gastric damage.

Conclusion: This study revealed that rohypnol induced gastric injury by suppressing glutathione content and COX-2 activity, and upregulating caspase 3-dependent apoptosis, which was partly reversed by rohypnol withdrawal.

Glutamine restores testicular glutathione-dependent antioxidant defense and upregulates NO/cGMP signaling in sleep deprivation-induced reproductive dysfunction in rats

Oxidative stress has been linked with sleep deprivation (SD)-induced pathological conditions and reproductive dysfunction. On the other hand, glutamine has been established to have antioxidant property. However, the impact of SD, with or without glutamine, on male reproductive function is yet to be elucidated. Thus, this study was designed to investigate the role of SD, with or without glutamine, on male reproductive function and possible associated mechanisms. Ten-week old male Wistar rats weighing 175.6 g± 0.42 were randomly assigned into vehicle that received per os (p.o.) distilled water, glutamine (1 g/kg; po), SD, and SD + glutamine that received treatments as glutamine and SD. Treatment/exposure lasted for 72 h. The results showed that SD led to reduced body weight, seminiferous luminal and epididymal sperm density, low sperm quality, increased testicular and epididymal malondialdehyde, uric acid, DNA fragmentation, and testicular injury markers. In addition, SD caused a reduction in reduced glutathione level and activities of superoxide dismutase, catalase, glucose-6-phosphate dehydrogenase, glutathione peroxidase, and glutathione-S-transferase. Also, SD increased tumor necrotic factor-α, interleukin-1β, and nuclear factor-kappa B levels. Furthermore SD led to impaired libido and erectile dysfunction, and suppression of circulatory nitric oxide, gonadotropins and testosterone, and penile cGMP. However, glutamine attenuated the effects induced by SD. Taken together, the findings of this study demonstrate that SD induces reproductive dysfunction via glutathione-dependent defense depletion and down-regulation of NO/cGMP signaling, which was abolished by glutamine supplementation.

Upregulation of Uric Acid Production and Caspase 3 Signalling Mediates Rohypnol-Induced Cardiorenal Damage

The global prevalence of illicit drug use is on the increase with attendant complications like cardiorenal collapse. One such substance of abuse is rohypnol. Despite its ban in most countries, it remains a popular substance of abuse. Whether or not rohypnol induces cardiorenal injury and the associated mechanism is yet to be elucidated. Therefore, the present study investigated the effect of rohypnol on cardiorenal integrity and functions, and glucolipid metabolism. Forty-eight male Wistar rats randomized into six groups (n = 8/group) received (per os) vehicle, low-dose (2 mg/kg) and high-dose (4 mg/kg) rohypnol once daily for twenty eight days, with or without a cessation period. Data revealed that rohypnol exposure irreversibly caused insulin resistance, hyperglycaemia, and dyslipidaemia. This was accompanied by reduced cardiorenal mass and impaired cardiorenal cytoarchitecture and function. Furthermore, rohypnol treatment promoted oxidative stress, inflammation, genotoxicity, and decreased cardiorenal activities of Na⁺-K⁺-ATPase, Ca²⁺-ATPase, and Mg²⁺-ATPase. These alterations were associated with enhanced uric acid generation and caspase 3 activity in the cardiorenal complex. Thus, this study reveals that rohypnol exposure triggers cardiorenal toxicity with incident insulin resistance, glucolipid and cardiorenal proton pump dysregulation, altered redox state, and inflammation via enhancement of uric acid generation and caspase 3-dependent mechanism.

Contraceptive potential of Andrographis paniculata is via androgen suppression and not induction of oxidative stress in male Wistar rats

Andrographis paniculata has been shown to be associated with male reproductive dysfunction, although the available data are scarce and inconsistent, and the associated mechanisms are elusive. Hormonal mechanism via hypothalamic-pituitary-testicular axis, and non-hormonal mechanism primarily through oxidative stress, are involved in the modulation of male reproductive function. We therefore, hypothesized that suppression of hypothalamic-pituitary-testicular axis and/or oxidative stress is involved in Andrographis paniculata-induced reproductive dysfunction. Male Wistar rats received either vehicle or Andrographis paniculata in varying doses of 250, 500, and 1000 mg/kg body weight daily for 8 weeks. Treatment with Andrographis paniculata led to reduced sperm count, motility, and viability. Andrographis paniculata treatment also resulted in distorted spermatogenesis and reduced serum testosterone. On the other hand, Andrographis paniculata led to reduction in the testicular content of malondialdehyde, nitric oxide, TNF-α, and IL-6, and testicular activities of xanthine oxidase and myeloperoxidase, but raised testicular levels of reduced glutathione content and enhanced activity of super oxide dismutase. However, body weight gain, and absolute and relative reproductive organ weights were similar across all the groups. These findings demonstrate that Andrographis paniculata induces reproductive toxicity via suppression of testosterone and not induction of oxidative stress. Therefore, Andrographis paniculata could be a potential and safe male contraceptive.

Irisin, Energy Homeostasis and Male Reproduction

Irisin is a novel skeletal muscle- and adipose tissue-secreted peptide. It is conventionally regarded as an adipomyokine and is a cleaved fragment of Fibronectin type III domain-containing protein 5 (FNDC5). It is involved in the browning of white adipose tissue, glucose tolerance, and reversing of metabolic disruptions. Fertility is closely linked to energy metabolism and the endocrine function of the adipose tissue. Moreover, there is established association between obesity and male infertility. Irisin bears strong therapeutic promise in obesity and its associated disorders, as well as shown to improve male reproductive functions. Thus, irisin is a molecule of great interest in exploring the amelioration of metabolic syndrome or obesity-induced male infertility. In this review we aim to enumerate the most significant aspects of irisin actions and discuss its involvement in energy homeostasis and male reproduction. Though current and future research on irisin is very promiscuous, a number of clarifications are still needed to reveal its full potential as a significant medicinal target in several human diseases including male infertility.

Omega-3 fatty acid rescues ischaemia/perfusion-induced testicular and sperm damage via modulation of lactate transport and xanthine oxidase/uric acid signaling

This study aimed to explore the potential antioxidant, anti-inflammatory, and anti-apoptotic effects of omega 3 fatty acid (Ω-3) in a rat model of testicular torsion/detorsion (T/D). Under ketamine/xylazine anaesthesia, age-matched adult male Wistar rats of comparable weight underwent sham-operation or testicular torsion by fixing the left testis rotated at 720° for two and half hours. After detorsion, animals were treated with either olive oil as vehicle or Ω-3 subcutaneously for three days. On post-operative day 3, rats were culled and the ipsilateral and contralateral testes, as well as obtained blood samples, were analyzed. Our findings revealed that T/D led to significant poor weight gain, distorted gross anatomy, and cytoarchitecture of the testes, low sperm quality, redox imbalance, and inflammation of the ipsilateral and contralateral testes. This was accompanied by reduced circulatory testosterone, a decline in testicular lactate metabolism and transport, upregulation of xanthine oxidase/uric acid signaling, and increased testicular DNA fragmentation. Administration of Ω-3 attenuated T/D-induced damage to the testes and sperm cells with a significant rise in the level of serum testosterone. Enhancement of lactate transport and down-regulation of xanthine oxidase/uric acid signaling by Ω-3 may be beneficial in protecting against T/D-related oxido-inflammatory damage and male infertility.

Co-administration of HAART and antikoch triggers cardiometabolic dysfunction through an oxidative stress-mediated pathway

Background

Antikoch and highly active anti-retroviral therapy are effective drugs in the management of tuberculosis and Human Immunodeficiency Virus, respectively. However, these cocktails have been independently associated with the aetiopathogenesis of metabolic syndrome. This study investigated whether or not the co-administration of antikoch and anti-retroviral, as seen in tuberculosis/Human Immunodeficiency Virus co-infection, will produce a similar effect. Also, it evaluated the role of glutathione and adenine deaminase/xanthine oxidase/uric acid signaling in antikoch/anti-retroviral-induced cardiometabolic dysfunction.

Methods

Male rats of Wistar strain were randomized into four groups: the control, which had 0.5 mL of distilled water as a vehicle, anti-Koch-treated rats that were administered a cocktail of anti-Koch, HAART-treated rats that had a combination of anti-retroviral drugs, and anti-Koch + HAART-treated rats that had treatments as anti-Koch-treated and HAART-treated rats. The treatment was once daily and lasted for eight weeks. One way-analysis of variance followed by Tukey’s posthoc test was used to test for significance and pairwise comparisons respectively.

Results

Although no changes in body weight gain and cardiac weight were noted, it was found that antikoch and/or HAART caused insulin resistance and elevated blood glucose level. In addition, antikoch and/or HAART led to dyslipidaemia, increased atherogenic indices, and elevated cardiac injury markers. These were accompanied by increased plasma and cardiac concentrations of malondialdehyde and nitric oxide, C-reactive protein, and myeloperoxidase activity, as well as suppressed activities of glutathione peroxidase and glutathione-S-transferase, and a fall in reduced glutathione level. The observed alterations were more pronounced in animals that received a combination of antikoch and HAART.

Conclusions

This study provides the first evidence that antikoch and/or HAART induce cardiometabolic dysfunction via glutathione suppression and up-regulation of adenine deaminase/xanthine oxidase/uric acid-dependent oxidative stress and inflammatory response. These events were associated with dyslipidaemia and increased atherogenic indices. This infers that regular monitoring of glucose level, insulin sensitivity, lipid profile, and oxido-inflammatory markers is important in patients on antikoch and/or HAART for prompt diagnosis and management of cardiometabolic disorder if it ensues.

Apoptotic inducement of neuronal cells by codeine: possible role of disrupted redox state and caspase 3 signaling

Background

Codeine, a common drug of abuse, has been reported to induce organ damage; however, there are scanty available data on the effects of codeine on the brain.

Objective

Thus, we tested the hypothesis that redox dysregulation and inflammation of the brain induced by codeine exposure is 8-OHdG and/or caspase 3-dependent.

Methods

New Zealand White rabbits (Oryctolagus cuniculus) received vehicle (control; n = 7), low-dose codeine (4 mg/kg/day p.o; n = 6), or high-dose codeine (10 mg/kg/day p.o; n = 6) for six weeks. Body weight was checked before and after the study.

Results

Findings showed that codeine exposure resulted in redox dysregulation (evident by elevated MDA and H₂O₂ accompanied by reduced enzymatic antioxidant activities), elevated MPO activity, and distorted cytoarchitecture of the brain tissue. The observed codeine-induced redox imbalance and brain inflammation was accompanied by depletion of neuronal and purkinje cells, reduced AchE activity, and elevated 8-OHdG levels and caspase 3 activity.

Conclusions

The current study demonstrates that chronic codeine use induces oxido-inflammatory response and apoptosis of the brain tissue that is associated with neuronal and purkinje cells injury, and impaired AchE activity through 8-OHdG and/or caspase 3-dependent pathway.

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Codeine led to redox dysregulation and inflammation of the brain.

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This was accompanied by distorted cytoarchitecture of the brain.

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Codeine also caused depletion of neuronal and purkinje cells with reduced acetylcholinesterase activity.

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Codeine-induced brain injury was mediated by upregulation of 8-OHdG/caspase 3 signaling.

HAART exacerbates testicular damage and impaired spermatogenesis in anti-Koch-treated rats via dysregulation of lactate transport and glutathione content

Highly active anti-retroviral therapy (HAART) is an effective anti-retroviral cocktail. Similarly, anti-Koch is highly potent against Mycobacterium tuberculosis. However, these drugs have been shown to impair male fertility. This study investigated the impact of HAART and anti-Koch, when used alone and co-administered, on testicular and sperm integrity. Thirty-two adult male Wistar rats were assigned randomly into four groups (n = 8), namely normal control, HAART-treated, anti-Koch-treated, and HAART + anti-Koch-treated. The doses of drugs were the human equivalent doses for rats. Administration was once daily per os and lasted for eight weeks. HAART aggravated anti-Koch-induced reduction in testicular and penile weights. In addition, anti-Koch also led to a distortion of testicular cytoarchitecture, disturbed spermatogenesis, and caused low sperm quality, including sperm dysmotility. More so, anti-Koch led to a significant elevation of uric acid and dysregulation of testicular lactate transport and glutathione content. These events were accompanied by enhanced lipid peroxidation and inflammation of the testicular tissue and reduced testicular and sperm DNA integrity. These adverse effects of anti-Koch were aggravated by co-administration of HAART. Thus, our results infer that HAART exacerbates anti-Koch-induced impairment of spermatogenesis and testicular and sperm toxicity through up-regulation of uric acid generation and dysregulation of lactate transport and glutathione system.

Codeine-induced sperm DNA damage is mediated predominantly by oxidative stress rather than apoptosis

ABSTRACTBackground: Opioids have been implicated to induce infertility. Although codeine remains the most used opioid for recreational purpose, no study has documented its effect on sperm quality. Elucidating the effect of codeine on sperm cells and the associated mechanisms may provide an insight into preventing drug-induced sperm damage. Twenty-one New Zealand white rabbits were randomized into three groups; control and codeine-treated. The codeine-treated groups received either 4 or 10mg/kg b.w of codeine for six weeks.Results: Codeine treatment led to significant decrease in sperm count, motility, viability, normal morphology, and sperm membrane integrity. This was associated with significant rise in sperm DNA fragmentation, oxidative damage, and caspase 3 activity. The percentage of sperm DNA fragmentation correlates positively with 8-hydroxy-2'-deoxyguanosine, a biomarker of oxidative DNA damage, and caspase 3 activity, a biomarker of apoptosis. The observed correlation was stronger between sperm DNA fragmentation and oxidative DNA damage than sperm DNA fragmentation and caspase 3 activity.Conclusion: This study revealed that chronic codeine exposure causes sperm DNA fragmentation and poor sperm quality primarily via oxidative stress rather than activation of caspase 3-dependent apoptosis. Findings of the present study may explain drug-induced male factor infertility, particularly, those associated with opioid use.

Suppression of uric acid generation and blockade of glutathione dysregulation by L-arginine ameliorates dichlorvos-induced oxidative hepatorenal damage in rats

Dichlorvos is a known risk factor for organ toxicity. The liver and kidney are essential metabolic tissues but it is unclear whether or not there is associated redox dyshomeostasis in both organs in physiological and pathological states. Uric acid accumulation and glutathione dysregulation have been implicated in the aetiopathogenesis of organ damage. The antioxidant potentials of L-arginine have been shown in various conditions. The present study was thus designed to investigate the synchrony in hepatic and renal uric acid and glutathione status in dichlorvos-induced hepatorenal damage and to probe the possible therapeutic role of L-arginine. Twenty-one male Wistar rats were treated with standard rat diet and water, dichlorvos, or dichlorvos and L-arginine. Our findings revealed that dichlorvos significantly impaired hepatic and renal functions, increased hepatic and renal malondialdehyde, but reduced glutathione and activities of superoxide dismutase, catalase, and glutathione peroxidase. These events were accompanied by increased accumulation of plasma, hepatic, and renal uric acid as well as reduced body weight gain, and hepatic and renal weights. Histopathological examinations revealed hepatic and renal architectural derangement and cellular necrosis and degeneration in dichlorvos-exposed rats. Interestingly, L-arginine reversed dichlorvos-induced systemic, hepatic and renal synchronous redox dyshomeostasis. L-arginine administration also improved hepatic and renal cytoarchitecture. It is thus concluded that dichlorvos triggered synchronous uric acid generation and glutathione alterations in the liver and kidney. L-arginine confers protection against dichlorvos-induced hepatorenal damage via suppression of uric acid generation and blockade of glutathione dysregulation.

HAART and anti-Koch's impair sexual competence, sperm quality and offspring quality when used singly and in combination in male Wistar rats

This study investigated the impact of the administration of HAART and anti-Koch's, singly and in combination, on sexual competence and birth statistics. Adult male Wistar rats were randomised into distilled water-treated control, HAART-treated, anti-Koch's-treated and HAART + anti-Koch's-treated groups. The 56-day oral treatment led to impaired sexual competence evident by significantly reduced motivation to mate, prolonged latencies of mount, intromissions, ejaculations and post-ejaculatory interval, as well as reduced frequencies of mount, intromissions and ejaculations. This was accompanied by significant reductions in penile erection reflex and penile grooming. HAART and anti-Koch's, when administered singly or in combination, also led to significant reductions in the circulatory follicle-stimulating hormone, luteinizing hormone, testosterone and intratesticular testosterone, but a significant rise in prolactin. Also, HAART and/or anti-Koch's significantly reduced sperm count, sperm motility, sperm viability and spermatozoa with normal morphology. Furthermore, HAART and anti-Koch's, separately or in combination, significantly lowered fertility capacity, litter size and litter weight and offspring survival. The deleterious effects of these drugs were more pronounced when combined. Findings of the present study revealed that HAART and/or anti-Koch's impair sexual competence via a testosterone-dependent hyperprolactinemia-mediated mechanism. These events are associated with reduced fertility capacity, poor sperm quality and lowered offspring survival.

Rohypnol-induced sexual dysfunction is via suppression of hypothalamic-pituitary-testicular axis: An experimental study in rats

Sexual activity is an essential part of reproductive functions and needed for the maintenance of fertility. Drugs, particularly substances of abuse, impair male reproductive function either by interrupting hormonal functions or through the nonhormonal pathways. This study evaluated the impact of Rohypnol use in sexual behaviour. Materials and methods: Thirty adult male Wistar rats of comparable weights (180-200 g) were randomly allocated into three groups, the control and low-dose and high-dose Rohypnol-treated groups. The control group received 0.5 ml of distilled water, while the low- and high-dose Rohypnol-treated groups received 2 mg/kg b.w and 4 mg/kg b.w of Rohypnol via oral lavage once daily for 28 days. Rohypnol significantly increased mount latency, intromission latency, ejaculation latency and post-ejaculatory interval, as well as lowered mount frequency, intromission frequency and ejaculation frequency. Rohypnol-induced sexual dysfunction was found to be associated with significant suppression of circulatory follicle-stimulating hormone, luteinising hormone, testosterone and oestrogen. The present study reveals that Rohypnol induces sexual dysfunction through suppression of hypothalamic-pituitary-testicular axis. It also implicates Rohypnol as a potential candidate for drug-induced infertility.

In vivo exposure to codeine induces reproductive toxicity: role of HER2 and p53/Bcl-2 signaling pathway

Several studies have implicated codeine use in the aetiopathogenesis of male infertility. The purpose of this study was to investigate the role of HER2, Ki67, oestrogen and p53/Bcl-2 signaling pathways and the possible outcome of codeine cessation on codeine-induced reproductive toxicity. Thirty adult male Wistar rats of comparable ages and weights were randomly allocated into 5 groups. The control animals received distilled water per os (p.o), while animals in the low-dose (LDC) and high dose (HDC) codeine-treated groups received 2 and 5 mg/kg/day of codeine respectively p.o for 6 weeks. The animals in the low-dose codeine recovery (LDC-R) and high-dose codeine recovery (HDC-R) groups received treatment as LDC and HDC respectively followed by another drug-free six weeks, recovery period. Cessation of codeine exposure led to a partial reversal of codeine-induced poor sperm quality, reduced litter size and weight, increased oxidative testicular injury, testicular apoptosis, and testicular DNA damage caused by codeine administration. Codeine-induced gonado-spermotoxicity was associated with a reduction of circulatory testosterone, suppression of testicular HER2, Ki67, and Bcl-2 expression, down-regulation of oestrogen signaling, and upregulation of testicular caspase 3 activities and p53 signaling pathway. Conclusion: Upregulation of oestrogen signaling associated with enhanced testicular HER2 and Ki67 expression during the recovery period is seemingly beneficial in protecting against codeine-related testicular injury and infertility.

Codeine-induced hepatic injury is via oxido-inflammatory damage and caspase-3-mediated apoptosis

Codeine (3-methylmorphine) is a known analgesic, antitussive, and antidiarrheal drug that is often abused for recreational purposes. It is metabolized in the liver via the cytochrome P450 system and thus hypothesized to induce hepatic injury especially when misused. Thus, the present study aimed at investigating changes in liver function, hepatic enzyme biomarker, proton pumps, antioxidant status, free radicals and TNF-α levels, as well as caspase 3 activities and hepatic DNA fragmentation after 6 weeks of oral codeine administration. Twenty-one male rabbits were randomized into 3 groups (n = 7). The control group had 1 ml of normal saline, while the low-dose and high-dose codeine groups received 4 and 10 mg/kg b.w of codeine respectively daily. The codeine-treated animals had significantly lower levels of serum proteins, increased activities of hepatic enzyme biomarkers and caspase 3, raised hepatic concentrations of free radicals and TNF-α, as well as increased hepatic DNA fragmentation. Codeine treatment also led to a significant decline in hepatic weight, activities of hepatic enzymatic antioxidant, Na⁺-K⁺-ATPase and Ca²⁺-ATPase. These alterations were more pronounced in high-dose codeine treated animals than in the low-dose group. Histopathological study showed moderate fatty degeneration of hepatic parenchyma, infiltration of the portal tract by inflammatory cells with dense collagen fibre deposition in codeine-treated animals. The present study revealed that codeine induced liver injury and hepatic DNA damage via caspase 3-dependent signaling by suppressing hepatic antioxidant status and enhancing free radical and TNF-α generation.

Codeine exerts cardiorenal injury via upregulation of adenine deaminase/xanthine oxidase and caspase 3 signaling

AIMS

Codeine treatment has been shown to be associated with glucolipid deregulation, though data reporting this are inconsistent and the mechanisms are not well understood. Perturbation of glutathione-dependent antioxidant defense and adenosine deaminase (ADA)/xanthine oxidase (XO) signaling has been implicated in the pathogenesis of cardiometabolic disorders. We thus, hypothesized that depletion of glutathione contents and upregulation of ADA/XO are involved in codeine-induced glucolipid deregulation. The present study also investigated whether or not codeine administration would induce genotoxicity and apoptosis in cardiac and renal tissues.

MATERIALS AND METHODS

Male New Zealand rabbits received per os distilled water or codeine, either in low dose (4 mg/kg) or high dose (10 mg/kg) for 6 weeks.

KEY FINDINGS

Codeine treatment led to reduced absolute and relative cardiac and renal mass independent of body weight change, increased blood glucose, total cholesterol (TC), triglycerides (TG), and low-density lipoprotein (LDL-C), as well as increased atherogenic indices and triglyceride-glucose index (TyG). Codeine administration significantly increased markers of cardiac and renal injury, as well as impaired cardiorenal functions. Codeine treatment also resulted in increased cardiac and renal malondialdehyde, Advanced Glycation Endproducts (AGE) and 8-hydroxydeoxyguanosine (8-OH-dG), and myeloperoxidase (MPO), ADA, XO, and caspase 3 activities. These observations were accompanied by impaired activities of cardiac and renal proton pumps.

SIGNIFICANCE

Findings of this study demonstrate that upregulation of ADA/XO and caspase 3 signaling are, at least partly, contributory to the glucolipid deregulation and cardiorenal injury induced by codeine.

Staging of the estrous cycle and induction of estrus in experimental rodents: an update

Background

Determination of the phases of the estrous cycle and induction of estrus (heat) in experimental animals remains useful, especially in reproductive function research.

Main body of the abstract

This review provides a detailed description and discusses extensively the variations observed in different phases of the estrous cycle in laboratory animals using rats and mice as examples. It also illustrates how these phases can be determined and how to induce estrus ‘heat’ when required. The phases of the estrous cycle can be determined using various methods such as visual assessment, vaginal smear/cytology, histology of female reproductive organs (vagina, uterus and ovaries), vaginal wall impedance assessment and determination of urine biochemical parameters. Female animals can be artificially brought to estrus phase ‘heat’ to make them receptive to male counterparts.

Conclusion

Determination of the length and phases of the estrous cycle and induction of estrus are useful in teaching and research and evaluating the effects of drugs/chemicals on the reproductive functions.

Lipid peroxidation in brain tissue following administration of low and high doses of arsenite and L-ascorbate in wistar strain rats

This study aimed at investigating the mechanism by which sodium arsenite induces brain injury and the role of L-ascorbate. Thirty adult (n=5) Wistar rats weighing between 140 and 160 g were used. Group 1 neither received sodium arsenite nor L-ascorbate (control), group 2 was administered low dose of arsenite only, group 3 received high dose of arsenite only, group 4 was administered L-ascorbate only, group 5 was administered low dose of arsenite and L-ascorbate, and group 6 received high dose of arsenite and L-ascorbate. M0 alon dialdehyde, MDA, levels were significantly increased in rats treated with high dose of arsenite when compared with those treated with low dose of arsenite. However, all treated groups except those treated with L-ascorbate only showed significant increase in MDA levels when compared with the control group. Rats treated with high dose of arsenite and L-ascorbate showed a significantly higher MDA level than those treated with low dose of arsenite and L-ascorbate. However, catalase activity, body weight gain, brain weight and mean food consumption were comparable across all groups. Brain tissue total protein was similar in all groups except in both groups treated with high dose of arsenite, where they were significantly reduced when compared with the control group. I0 n conclusion, sodium arsenite treatment induces brain injury via a mechanism associated with lipid peroxidation, but not catalase-dependent. However, L-ascorbate ameliorates arsenite-induced oxidative injury in the brain. L-ascorbate antioxidative potential in alleviating arsenite-induced brain injury is dependent on the concentration of arsenite.

Variability in cardiovascular functions and baroflex sensitivity following inhalation of petroleum hydrocarbons

Objective:

Although petroleum products are useful chemical compounds which form an integral part of our modern technology, they have been reported to cause deleterious effect on health following their inhalation. Petroleum hydrocarbons-dependent health hazards and their mechanisms have been associated with the routes of administration. This study, therefore, aimed at the isolation and chemical characterization of various petroleum products, and also investigating in rat model of Sprague dawley strain, the variability in cardiovascular functions and possible mechanism following inhalation of petroleum products.

Materials and Methods:

Control rats were not exposed to any form of petroleum products, while the petrol-exposed, diesel-exposed, and kerosene-exposed were exposed to petrol, diesel, and kerosene respectively.

Results:

When compared with the controls, all exposed groups showed a significant (P<0.05) increase in the systolic blood pressure, diastolic blood pressure, mean arterial pressure (MAP), and heart rate (HR). In comparison with the control, exposure to petroleum products also led to significant (P<0.05) increase in baroreflex sensitivity in the diesel- and kerosene-exposed rats. Baroreflex sensitivity was comparable in the control and petrol-exposed rats (P>0.05). Body weight gain was significantly (P<0.05) reduced in petroleum products exposed rats.

Conclusion:

These results suggest that the variability of cardiovascular functions associated with inhalation of petroleum products is in attendant to baroreflex sensitivity and resetting of arterial pressure.

Comparison of the haemodynamic effects of pyrethroid insecticide and amodiaquine in rats

Malaria infection is a common cause of morbidity and mortality especially in the tropics and subtropics. This has led to the increased prophylactic use ofpyrethroid insecticides and/or Amodiaquine (Aq) to combat the parasitic protozoan infection. The aim of this study was to investigate the comparative haemodynamic effects of pyrethroid insecticide and amodiaquine in rats. Experimental rats were randomly allocated into seven groups of five rats in each. Groups 1, 2 and 3 were exposed to pyrethroid by inhalation for 1, 2 and 3 min, respectively, while groups 4, 5 and 6 were administered Aqper oral at 5, 10 and 15 mg kg(-1) b.wt., respectively. Control rats were neither exposed to pyrethroid nor administered Aq. Pyrethroid insecticide led to reduced systolic, diastolic and mean arterial pressures, but increased pulse pressure. Aq treatment did not cause any significant variation in haemodynamic variables. Heart rate was comparable in all groups. Results from the study provide extended safety/toxicity profile for pyrethroid use and Aq treatment. Aq showed no cardiotoxic potential, while pyrethroids have hypotensive effect. It is thus recommended that exposure to pyrethroids should be minimized.

Effects of pyrethroid insecticide exposure on haematological and haemostatic profiles in rats

High malaria burden has led to the increase use of insecticides in the tropics and subtropics. This study thus aimed at assessing the haematological effects and associated haemostatic alteration of pyrethroid insecticide exposure using experimental animal model. Rats of comparable ages and weights were randomized into four groups (A-D). Rats in groups B, C and D were exposed to pyrethroid insecticide by inhalation for 1, 2 and 3 min daily respectively for three weeks. Rats in group A (control) were not exposed. Haematological and haemostatic variables were comparable in all groups (< 0.05). Results from the study show that minimal exposure to pyrethroids is safe.

Hepatotherapeutic effect of Aloe vera in alcohol-induced hepatic damage

There is a lack of reliable hepatotherapeutic drugs in modern medicine in the management of alcohol/drug-induced liver damage. Aloe vera extract has been used in folklore medicine for its medicinal values. This study evaluates the hepatotherapeutic activity of aqueous extract of Aloe vera gel in rats. Sprague-Dawley rats were divided into three groups; the negative control, positive control and the extract-treated groups. The negative control received only distilled water daily. The positive control received alcohol, while the extract-treated group received aqueous extract of Aloe vera and alcohol. Hepatotoxicity was induced in the positive control and extract-treated rats with alcohol. The hepatotherapeutic effect was evaluated by performing an assay of the serum total bilirubin, alkaline phosphatase, aspartate and alanine transaminases and liver histopathology. Alanine transaminase activities were comparable in all groups. Alcohol treatment alone significantly (p < 0.05) increased total serum bilirubin, alkaline phosphatase and aspartate transaminase activities. Alcohol-induced hepatic dysfunction was abrogated by Aloe vera extract. Histopathological examination revealed that alcohol induced hepatic damage. Aloe vera treatment maintained hepatic architecture similar to that seen in the control. This study shows that aqueous extract of Aloe vera gel is hepatotherapeutic and thus lends credence to the use of the plant in folklore medicine in the management of alcohol-induced hepatic dysfunction.

Effect of increased dietary calcium on body weight, food and water intake in oral contraceptive treated female rats

The effects of high calcium diet on body weight in OC treated rats are unknown. This study therefore investigated the effect of increasing dietary calcium from 0.9% to 2.5% on body weight, food ingestion, water intake, heart weight index and renal weight index in female Sprague-Dawley rats treated with a combination of OC steroids (ethinyloestradiol + norgestrel). The rats were assigned into three groups of average of 11 rats each; control, OC-treated and OC + Calcium &ndash; treated groups and administered orally for 10 weeks. Food and water intake, body weight, cardiac weight index, left ventricular weight index, renal weight index and serum calcium level were determined. The result shows that OC treated rats had significantly lower serum calcium concentration, body weight gain, food, water and calcium intake than those of the control rats. The OC + Calcium &ndash; treated rat had significantly higher serum calcium concentration, food, water and calcium intake but significantly lower body weight than those of the OC - treated rats. OC + Calcium - treated rats had significantly higher water intake, calcium intake and significantly lower body weight and food intake when compared with the control rats. Cardiac weight index and renal weight index was comparable in all groups. In conclusion, combined OC-induced reduction in weight gain might be associated with inhibition of the feeding center and consequent inhibition of the thirst center. Co-administration of dietary calcium augmented the reduction in weight gain seen in OC-treated rats probably by further suppression of the feeding and thirst centers.