Browsing by Author "Plessis, Stefan S du"

Now showing 1 - 7 of 7

Descriptive histomorphological evaluation of the testis and caudal epididymis following treatment with rooibos (Aspalathus linearis), honeybush (Cyclopia intermedia) and sutherlandia (Lessertia frutescens) in healthy and streptozotocininduced diabetic rats
(2021) Omolaoye, Temidayo S.; Plessis, Stefan S du
Objective: To evaluate the testis and the cauda epididymis after treating both healthy and diabetic rats with rooibos (Aspalathus linearis), honeybush (Cyclopia intermedia), and sutherlandia (Lessertia frutescens), respectively. Methods: Ninety male Wistar rats were randomly divided into nine groups (n=10 per group). Fifty rats were randomized to receive tap water, 0.1 M citrate buffer, 2.0% fermented rooibos, 4.0% fermented honeybush, or 0.2% unfermented sutherlandia. Diabetes was induced via a single intraperitoneal injection of streptozotocin (STZ) at 45 mg/kg in 40 rats. The diabetic rats were randomized to receive tap water, 2.0% fermented rooibos, 4.0% fermented honeybush, or 0.2% unfermented sutherlandia. Rats were sacrificed after seven weeks of diabetic induction. Blood was collected for hormonal assay, while the testes and caudal epididymis were retrieved for histomorphological evaluations. Results: Diabetic rats treated with 2.0% fermented rooibos exhibited a significant increase in fasting plasma glucose (FPG) versus the vehicle group (P=0.002), and a 3.6% decrease compared to the diabetic control group (P>0.05). Diabetic rats treated with honeybush or sutherlandia showed 23.6% and 15.4% decrease in FPG when compared to the diabetic control group, respectively (both P>0.05). The diabetic control rats had a significant decrease in the percentage of histologically normal seminiferous tubules compared to the control group (P=0.049). There was 21.0%, 14.0%, and 5.4% rise in the percentage of normal seminiferous tubules in diabetic rats receiving rooibos, honeybush or sutherlandia, respectively, compared to the diabetic control group. The infusion control groups (rooibos, honeybush and sutherlandia) showed normal seminiferous tubules, presence of spermatozoa in the epididymal lumen, and had normal overall architecture. Both testicular and epididymal morphology were altered in the diabetic control group, but these disruptions were mildly ameliorated by rooibos, honeybush, and sutherlandia. Conclusions: The detrimental effects of diabetes on the histomorphological architecture of the testis and epididymis are mildly ameliorated by the infusions (2.0% fermented rooibos, 4.0% fermented honeybush, and 0.2% unfermented sutherlandia).
Fertility and pregnancy outcome among women undergoing assisted reproductive technology treatment in Windhoek, Namibia
(2021) Plessis, Stefan S du
Purpose: Infertility has been defined as a couple's failure to conceive after regular and unprotected coitus for 1 year or six months, depending on the age of the female counterpart. Although infertility can result from both the male and/or the female, often the female partner faces pressure since it is believed in some African cultures that a woman without children is like a tree without leaves. The aim of this study was to determine the prevalence of successful pregnancy outcomes among infertile women undergoing assisted reproductive technology (ART) treatment at the Cape Windhoek Fertility Clinic. Methods: This was a prospective and descriptive cross-sectional case reference study encompassing 178 infertile women visiting the Cape Windhoek Fertility Clinic for ART treatment. Results: The vast majority of the participants (81.5%) were married women. From the 178 infertile women, 96 (53.9%) suffered from primary and 82 (46.1%) from secondary infertility. The predominant cause of complications for infertility among the women studied was defective ovulation (28.7%) and the most common ART treatment administered was IVF/ICSI (52.2%). Only a third (33.1%) of the women who received ART treatment eventually fell pregnant. Conclusion: The outcome of this study may not give a clear indication of the prevalence of infertility among women in the entire Namibian nation due to the costs involved with ART treatment offered mainly at privately owned hospitals and/or clinics, thereby resulting in those who cannot afford treatment to be left out despite being infertile.
The mutagenic effect of tobacco smoke on male fertility
(2021) Omolaoye, Temidayo S.; Boillat, Thomas; Loney, Tom; Plessis, Stefan S du
Abstract: Despite the association between tobacco use and the harmful effects on general health as well as male fertility parameters, smoking remains globally prevalent. The main content of tobacco smoke is nicotine and its metabolite cotinine. These compounds can pass the blood-testis barrier, which subsequently causes harm of diverse degree to the germ cells. Although controversial, smoking has been shown to cause not only a decrease in spermmotility, spermconcentration, and an increase in abnormal sperm morphology, but also genetic and epigenetic aberrations in spermatozoa. Both animal and human studies have highlighted the occurrence of sperm DNA-strand breaks (fragmentation), genome instability, genetic mutations, and the presence of aneuploids in the germline of animals and men exposed to tobacco smoke. The question to be asked at this point is, if smoking has the potential to cause all these genetic aberrations, what is the extent of damage? Hence, this review aimed to provide evidence that smoking has a mutagenic effect on sperm and how this subsequently affects male fertility. Additionally, the role of tobacco smoke as an aneugen will be explored.We furthermore aim to incorporate the epidemiological aspects of the aforementioned and provide a holistic approach to the topic.
The Role of Selected Natural Biomolecules in Sperm Production and Functionality
(2021) Plessis, Stefan S du
Abstract: Emerging evidence from in vivo as well as in vitro studies indicates that natural biomolecules may play important roles in the prevention or management of a wide array of chronic diseases. Furthermore, the use of natural compounds in the treatment of male sub- or infertility has been proposed as a potential alternative to conventional therapeutic options. As such, we aimed to evaluate the effects of selected natural biomolecules on the sperm production, structural integrity, and functional activity. At the same time, we reviewed their possible beneficial or adverse effects on male reproductive health. Using relevant keywords, a literature search was performed to collect currently available information regarding molecular mechanisms by which selected natural biomolecules exhibit their biological effects in the context of male reproductive dysfunction. Evidence gathered from clinical trials, in vitro experiments and in vivo studies suggest that the selected natural compounds affect key targets related to sperm mitochondrial metabolism and motion behavior, oxidative stress, inflammation, DNA integrity and cell death. The majority of reports emphasize on ameliorative, stimulating and protective effects of natural biomolecules on the sperm function. Nevertheless, possible adverse and toxic behavior of natural compounds has been indicated as well, pointing out to a possible dosedependent impact of natural biomolecules on the sperm survival and functionality. As such, further research leading to a deeper understanding of the beneficial or adverse roles of natural compounds is necessary before these can be employed for the management of male reproductive dysfunction.
SARS-COV-2 (Covid-19) and male fertility: Where are we?
(2020) Plessis, Stefan S du
Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS􀀀 COV-2), a single-stranded RNA virus, was found to be the causal agent of the disease called coronavirus disease. During December 2019, China informed the World Health Organization (WHO) of an outbreak of cases of pneumonia of unknown etiology, which caused severeacute respiratory distress. The disease was termed coronavirus disease 2019 (Covid-19). Due to alarming levels of spread and severity, on the 11th of March 2020, the WHO declared the outbreak as a global pandemic. As of September 14, 2020, more than 29 million cases have been reported, with over 900,000 deaths globally. Since the outbreak, although not conclusive, discoveries have been made regarding the understanding of the epidemiology, etiology, clinical features, clinical treatment, and prevention of the disease. SARS􀀀 COV-2 has been detected in saliva, respiratory fluids, blood, urine, and faeces. Findings are however controversial regarding its presence in the semen or the testis. Hence, this review aimed to further analyse the literature concerning (i) the effects of previously identified human coronaviruses on male fertility (ii) the impact of Covid-19 on male fertility and (iii) the implication for general health in terms of infection and transmission.
SARS-CoV-2 Vaccine Effects on Semen Parameters: A Systematic Review and Meta-Analysis
(2022-12) Omolaoye, Temidayo S; Plessis, Stefan S du
Objective: Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) epitomizes the best preventative SARS-CoV-2 infection strategy to counteract the severe consequences of infection. However, concerns have been raised that the vaccines could have an adverse effect on sperm function and overall reproductive health. This combined systematic review and meta-analysis aimed to investigate the effects of different available SARS-CoV-2 vaccines on semen parameters. Methods: A systematic PubMed, Scopus, Google Scholar, ScienceDirect, LILACS (Literatura Latinoamericana y del Caribe en Ciencias de la Salud), and Scilit database literature search until mid-June 2022 was conducted. Prospective and retrospective studies were eligible. No limitation was placed on language. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were thereafter obtained. Results: Upon search completion, 122 studies were identified and retrieved and 110 were excluded, while the remaining 12 independent studies evaluating the effects of coronavirus disease 2019 (COVID-19) vaccines on semen parameters were included in this review. The total number of men included was 1551, aged 22.4-48 years. Following meta-analysis, the SMD summary measure with 95% CI for each semen parameter included a concentration of 0.22 (0-0.22); Total sperm count of 0.11 (0.18-0.24); Total motility of 0.02 (0.05-0.09); Volume of 0.02 (-0.1-0.14); Vitality of 0.55 (-0.19-0.29), progressive motility of -0.43 (-0.54 to -0.32); Total motile sperm count of -0.38 (-0.44 to -0.31); And normal morphology of 0.42 (-0.54 to -0.3). In brief, the total sperm count was slightly increased post-vaccination, while progressive motility, total motile sperm count, and normal morphology were marginally reduced post-vaccination, according to the meta-analysis. Conclusions: No effects were observed regarding sperm viability and semen volume since the results of all the studies crossed the line of no effect. All seminal parameters analyzed showed a negligible or small change in relation to the vaccination effect. Furthermore, the parameters remained within the normal World Health Organization reference ranges, making the clinical significance unclear. Therefore, based on these results, it appears that vaccination does not have negative effects on semen quality. The individual study findings suggested that COVID-19 vaccines are not associated with decreased semen parameters.
Seminal plasma metabolomics profiles following long (4–7 days) and short (2 h) sexual abstinence periods
(2021) Plessis, Stefan S du
Objective: Metabolomic profiling of seminal plasma has been suggested as a possible approach for a fast and non-invasive male infertility evaluation diagnosis. However, metabolomics profiles in normozoospermic men have not been thoroughly investigated, and the influence of ejaculation-abstinence has not been described. To provide interim reference values and find associations between the metabolomics profiles of human seminal plasma and length of ejaculation-abstinence period in normozoospermic men. Study design: Semen samples collected after long (4–7 days) and short abstinence (2 h) from 31 normozoospermic males were assessed for routine quality parameters before the seminal plasma was separated by centrifugation. Metabolomics profiles of the seminal plasma were then determined using untargeted Nuclear Magnetic Resonance Spectroscopy. Results: In total, 30 metabolites were identified. Pyruvate showed a higher concentration, while fructose, acetate, choline, methanol, N-acetylglucosamine, O-acetylcarnitine, uridine, and sn-glycero-3- phosphocoline showed lower concentrations in samples collected after short abstinence (vs. long). All metabolites showed lower absolute amounts (volume x concentration) following shorter abstinence. However, the lower sperm concentration in samples collected after short abstinence resulted in higher absolute amounts of pyruvate and taurine per spermatozoa: pyruvate 1.92 (1.12–3.87) vs. 1.29 (0.83– 2.62) (P < 0.001) and taurine 0.58 (0.36–0.92) vs. 0.43 (0.28–0.95) (P < 0.05) ng/106 spermatozoa. Simultaneously, there was a higher percentage of progressively motile spermatozoa in samples collected after the short abstinence. Conclusion: The generally lower concentrations of seminal metabolites after short abstinence periods may be related to the shorter time available for secretion and collection of these metabolites by the accessory glands and the epididymides. The concomitant lower number of spermatozoa in the second ejaculate resulted in increased absolute amounts of pyruvate and taurine per spermatozoa, accompanied by increased spermatozoa motility in these samples. The simultaneous increase in percentages of motile spermatozoa and absolute amounts of pyruvate and taurine per spermatozoa after shorter abstinence might indicate that these two metabolites play a more critical role in sperm motility, which should be further investigated in future studies.