Gonadotropin-inhibitory hormone and its receptors in teleosts: Physiological roles and mechanisms of actions.

Gonadotropin-inhibitory hormone (GnIH) was the first reported hypothalamic neuropeptide inhibiting reproduction in vertebrates. Since its discovery in the quail brain, its orthologs have been identified in a variety of vertebrate species and even protochordates. Depending on the species, the GnIH precursor polypeptides comprise two, three or four mature peptides of the RFamide family. It has been well documented that GnIH inhibits reproduction at the brain-pituitary-gonadal levels and participates in metabolism, stress response, and social behaviors in birds and mammals. However, most studies in fish have mainly been focused on the physiological roles of GnIH in the control of reproduction and results obtained are in some cases conflicting, leaving aside its potential roles in the regulation of other functions. In this manuscript we summarize the information available in fish with respect to the structural diversity of GnIH peptides and functional roles of GnIH in reproduction and other physiological processes. We also highlight the molecular mechanisms of GnIH actions on target cells and possible interactions with other neuroendocrine factors.

Human-induced pluripotent stem cell-derived ovarian support cell co-culture improves oocyte maturation in vitro after abbreviated gonadotropin stimulation.

STUDY QUESTION: Can in vitro maturation (IVM) and developmental competence of human oocytes be improved by co-culture with ovarian support cells (OSCs) derived from human-induced pluripotent stem cells (hiPSCs)? SUMMARY ANSWER: OSC-IVM significantly improves the rates of metaphase II (MII) formation and euploid Day 5 or 6 blastocyst formation, when compared to a commercially available IVM system. WHAT IS KNOWN ALREADY: IVM has historically shown highly variable performance in maturing oocytes and generating oocytes with strong developmental capacity, while limited studies have shown a positive benefit of primary granulosa cell co-culture for IVM. We recently reported the development of OSCs generated from hiPSCs that recapitulate dynamic ovarian function in vitro. STUDY DESIGN, SIZE, DURATION: The study was designed as a basic science study, using randomized sibling oocyte specimen allocation. Using pilot study data, a prospective sample size of 20 donors or at least 65 oocytes per condition were used for subsequent experiments. A total of 67 oocyte donors were recruited to undergo abbreviated gonadotropin stimulation with or without hCG triggers and retrieved cumulus-oocyte complexes (COCs) were allocated between the OSC-IVM or control conditions (fetal-like OSC (FOSC)-IVM or media-only IVM) in three independent experimental design formats. The total study duration was 1 April 2022 to 1 July 2023. PARTICIPANTS/MATERIALS, SETTING, METHODS: Oocyte donors between the ages of 19 and 37 years were recruited for retrieval after informed consent, with assessment of anti-Mullerian hormone, antral follicle count, age, BMI and ovarian pathology used for inclusion and exclusion criteria. In experiment 1, 27 oocyte donors were recruited, in experiment 2, 23 oocyte donors were recruited, and in experiment 3, 17 oocyte donors and 3 sperm donors were recruited. The OSC-IVM culture condition was composed of 100 000 OSCs in suspension culture with hCG, recombinant FSH, androstenedione, and doxycycline supplementation. IVM controls lacked OSCs and contained either the same supplementation, FSH and hCG only (a commercial IVM control), or FOSCs with the same supplementation (Media control). Experiment 1 compared OSC-IVM, FOSC-IVM, and a Media control, while experiments 2 and 3 compared OSC-IVM and a commercial IVM control. Primary endpoints in the first two experiments were the MII formation (i.e. maturation) rate and morphological quality assessment. In the third experiment, the fertilization and embryo formation rates were assessed with genetic testing for aneuploidy and epigenetic quality in blastocysts. MAIN RESULTS AND THE ROLE OF CHANCE: We observed a statistically significant improvement (∼1.5×) in maturation outcomes for oocytes that underwent IVM with OSCs compared to control Media-IVM and FOSC-IVM in experiment 1. More specifically, the OSC-IVM group yielded a MII formation rate of 68% ± 6.83% SEM versus 46% ± 8.51% SEM in the Media control (P = 0.02592, unpaired t-test). FOSC-IVM yielded a 51% ± 9.23% SEM MII formation rate which did not significantly differ from the media control (P = 0.77 unpaired t-test). Additionally, OSC-IVM yielded a statistically significant ∼1.6× higher average MII formation rate at 68% ± 6.74% when compared to 43% ± 7.90% in the commercially available IVM control condition (P = 0.0349, paired t-test) in experiment 2. Oocyte morphological quality between OSC-IVM and the controls did not significantly differ. In experiment 3, OSC-IVM oocytes demonstrated a statistically significant improvement in Day 5 or 6 euploid blastocyst formation per COC compared to the commercial IVM control (25% ± 7.47% vs 11% ± 3.82%, P = 0.0349 logistic regression). Also in experiment 3, the OSC-treated oocytes generated blastocysts with similar global and germline differentially methylated region epigenetic profiles compared commercial IVM controls or blastocysts after either conventional ovarian stimulation. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: While the findings of this study are compelling, the cohort size remains limited and was powered on preliminary pilot studies, and the basic research nature of the study limits generalizability compared to randomized control trials. Additionally, use of hCG-triggered cycles results in a heterogenous oocyte cohort, and potential differences in the underlying maturation state of oocytes pre-IVM may limit or bias findings. Further research is needed to clarify and characterize the precise mechanism of action of the OSC-IVM system. Further research is also needed to establish whether these embryos are capable of implantation and further development, a key indication of their clinical utility. WIDER IMPLICATIONS OF THE FINDINGS: Together, these findings demonstrate a novel approach to IVM with broad applicability to modern ART practice. The controls used in this study are in line with and have produced similar to findings to those in the literature, and the outcome of this study supports findings from previous co-culture studies that found benefits of primary granulosa cells on IVM outcomes. The OSC-IVM system shows promise as a highly flexible IVM approach that can complement a broad range of stimulation styles and patient populations. Particularly for patients who cannot or prefer not to undergo conventional gonadotropin stimulation, OSC-IVM may present a viable path for obtaining developmentally competent, mature oocytes. STUDY FUNDING/COMPETING INTEREST(S): A.D.N., A.B.F., A.G., B.P., C.A., C.C.K., F.B., G.R., K.S.P., K.W., M.M., P.C., S.P., and M.-J.F.-G. are shareholders in the for-profit biotechnology company Gameto Inc. P.R.J.F. declares paid consultancy for Gameto Inc. P.C. also declares paid consultancy for the Scientific Advisory Board for Gameto Inc. D.H.M. has received consulting services from Granata Bio, Sanford Fertility and Reproductive Medicine, Gameto, and Buffalo IVF, and travel support from the Upper Egypt Assisted Reproduction Society. C.C.K., S.P., M.M., A.G., B.P., K.S.P., G.R., and A.D.N. are listed on a patent covering the use of OSCs for IVM: U.S. Provisional Patent Application No. 63/492,210. Additionally, C.C.K. and K.W. are listed on three patents covering the use of OSCs for IVM: U.S. Patent Application No. 17/846,725, U.S Patent Application No. 17/846,845, and International Patent Application No.: PCT/US2023/026012. C.C.K., M.P.S., and P.C. additionally are listed on three patents for the transcription factor-directed production of granulosa-like cells from stem cells: International Patent Application No.: PCT/US2023/065140, U.S. Provisional Application No. 63/326,640, and U.S. Provisional Application No. 63/444,108. The remaining authors have no conflicts of interest to declare.

Effectiveness of oestrogen pretreatment in patients with expected poor ovarian response (POSEIDON groups 3 and 4) undergoing GnRH antagonist protocol: study protocol for a randomised controlled trial.

INTRODUCTION: Women characterised by diminished ovarian reserve are considered to have poor ovarian response (POR) according to Patient-Oriented Strategies Encompassing IndividualizeD Oocyte Number (POSEIDON) criteria. Patients in this population often have a poor prognosis for treatment with assisted reproductive technology. In previous studies, oestrogen pretreatment before ovarian stimulation has been shown to have a beneficial effect. However, recent studies presented conflicting conclusions. This study aims to evaluate the effectiveness of oestrogen pretreatment in patients with expected POR (POSEIDON groups 3 and 4) undergoing gonadotrophin releasing hormone antagonist (GnRH-ant) protocol. METHODS AND ANALYSIS: A prospective superiority randomised parallel controlled trial will be conducted at a tertiary university-affiliated hospital. A total of 316 patients will be randomly divided into two groups at a ratio of 1:1. In the intervention group, oral oestrogen pretreatment will be administered from day 7 after ovulation until day 2 of the next menstrual cycle. Afterwards, a flexible GnRH-ant protocol will be initiated. The control group will receive no additional intervention beyond routine ovarian stimulation. The primary outcome is the number of oocytes retrieved. Secondary outcomes include the total number of retrieved metaphase II oocytes, average daily dose of gonadotropin, total gonadotropin dose and duration of ovarian stimulation, cycle cancellation rate, top quality embryos rate, blastocyst formation rate, embryo implantation rate, clinical pregnancy rate, early miscarriage rate and endometrial thickness on trigger day. All data will be analysed according to the intention-to-treat and per-protocol principles. ETHICS AND DISSEMINATION: The ethical approval has been confirmed by the reproductive ethics committee of the affiliated hospital of Shandong University of Traditional Chinese Medicine (SDUTCM/2022.9.20). In addition, written informed consent will be obtained from all the participants before the study. The results will be disseminated via publications. TRIAL REGISTRATION NUMBER: ChiCTR2200064812.

Systematic review of acupuncture to improve ovarian function in women with poor ovarian response.

Objective: To determine the effect of acupuncture in treating poor ovarian response (POR). Methods: We searched MEDLINE (via PubMed), EMBASE, Allied and Complementary Medicine Database, CNKI, CBM, VIP database, Wanfang Database, and relevant registration databases from inception to January 30, 2023. In this review, both Chinese and English peer-reviewed literature were included. Only randomized controlled trials (RCTs) using acupuncture as an intervention for POR patients undergoing in vitro fertilization were considered. Results: Seven clinical randomized controlled trials (RCTs) were eventually included for comparison (516 women). The quality of included studies was generally low or very low. For the meta-analysis, seven studies showed that compared with controlled ovarian hyperstimulation (COH) therapy, acupuncture combined with COH therapy could significantly increase the implantation rate (RR=2.13, 95%CI [1.08, 4.21], p=0.03), the number of oocytes retrieved (MD=1.02, 95%CI [0.72, 1.32], p<0.00001), the thickness of endometrium (MD=0.54, 95%CI [0.13, 0.96], p=0.01), and the antral follicle count (MD=1.52, 95%CI [1.08, 1.95], p<0.00001), reduce follicle-stimulating hormone (FSH) levels (MD=-1.52, 95%CI [-2.41, -0.62], p=0.0009) and improve estradiol (E2) levels (MD=1667.80, 95%CI [1578.29, 1757.31], p<0.00001). Besides, there were significant differences in the duration of Gn (MD=0.47, 95%CI [-0.00, 0.94], p=0.05) between the two groups. However, no statistical variation was observed in improving clinical pregnancy rate (CPR), fertilization rate, high-quality embryo rate, luteinizing hormone (LH) value, anti-mullerian hormone (AMH) value, or reducing the dose of gonadotropin (Gn) values between the acupuncture plus COH therapy group and the COH therapy group. Conclusion: Acupuncture combined with COH therapy is doubtful in improving the pregnancy outcome of POR patients. Secondly, acupuncture can also improve the sex hormone level of POR women, and improve ovarian function. Furthermore, more RCTs of acupuncture in POR are needed to be incorporated into future meta-analyses. Systematic review registration: PROSPERO, identifier CRD42020169560.

Management of congenital hypogonadotropic hypogonadism in females.

This review explores the challenges in the diagnosis of hypogonadotropic hypogonadism, the transition of care from paediatric to adult care and the considerable health implications of this condition. The role gynaecologists and general practitioners have in managing hormone replacement therapy and reproductive potential is also highlighted. The fertility treatment options, which include ovulation induction with gonadotrophins and in-vitro fertilisation, are discussed in detail along with highlighting the fact that anovulation and markers of low ovarian reserve prior to priming treatment may not be reflective of poor reproductive potential. The holistic management of women with hypogonadotropic hypogonadism is still not standardised and evidence for subfertility management is scarce. This review aims to highlight this concern and provide guidance by evaluating current evidence.

IGF1 gene therapy in middle-aged female rats delays reproductive senescence through its effects on hypothalamic GnRH and kisspeptin neurons.

The process of aging is the result of progressive loss of homeostasis and functional body impairment, including the central nervous system, where the hypothalamus plays a key role in regulating aging mechanisms. The consequences of aging include a chronic proinflammatory environment in the hypothalamus that leads to decreased secretion of gonadotropin-releasing hormone (GnRH) and impairs kisspeptin neuron functionality. In this work, we investigated the effect of insulin-like growth factor 1 (IGF1) gene therapy on hypothalamic kisspeptin/GnRH neurons and on microglial cells, that mediate the inflammatory process related with the aging process. The results show that IGF1 rats have higher kisspeptin expression in the anteroventral periventricular (AVPV) nucleus and higher immunoreactivity of GnRH in the arcuate nucleus and median eminence. In addition, IGF1-treated animals exhibit increased numbers of Iba1+ microglial cells and MHCII+/Iba1+ in the AVPV and arcuate nuclei. In conclusion, IGF1 gene therapy maintains kisspeptin production in the AVPV nucleus, induces GnRH release in the median eminence, and alters the number and reactivity of microglial cells in middle-aged female rats. We suggest that IGF1 gene therapy may have a protective effect against reproductive decline.

Effects of undernutrition and low energy availability on reproductive functions and their underlying neuroendocrine mechanisms.

It has been well established that undernutrition and low energy availability disturb female reproductive functions in humans and many animal species. These reproductive dysfunctions are mainly caused by alterations of some hypothalamic factors, and consequent reduction of gonadotrophin-releasing hormone (GnRH) secretion. Evidence from literature suggests that increased activity of orexigenic factors and decreased activity of anorexigenic/satiety-related factors in undernourished conditions attenuate GnRH secretion in an integrated manner. Likewise, the activity of kisspeptin neurons, which is a potent stimulator of GnRH, is also reduced in undernourished conditions. In addition, it has been suggested that gonadotrophin-inhibitory hormone, which has anti-GnRH and gonadotrophic effects, may be involved in reproductive dysfunctions under several kinds of stress conditions. It should be remembered that these alterations, i.e., promotion of feeding behavior and temporary suppression of reproductive functions, are induced to prioritize the survival of individual over that of species, and that improvements in metabolic and nutritional conditions should be considered with the highest priority.

[Effects of time of recombinant luteinized hormone supplementation on pregnancy outcomes of women with advanced reproductive age during follicular-phase long protocol].

Objective: To investigate the effects of supplementation of recombinant luteinized hormone (rLH) and its timing on pregnancy outcomes of patients at 35 years or older with follicular-phase long protocol. Methods: Clinical data of women undergoing in vitro fertilization or intracytoplasmic sperm injection with follicular-phase long protocol was collected and retrospectively analyzed in the First Affiliated Hospital of Nanjing Medical University from January 2017 to December 2019. There were 558 patients at 35 years or older included in this study, and they were divided into three groups: group A was patients with only recombinant follicle stimulating hormone (rFSH) stimulation (127 cycles), group B was patients with rFSH plus rLH supplementation in the mid-follicular phase (141 cycles), and patients in group C received combined rFSH and rLH from the first day of ovarian stimulation (290 cycles). The basic characteristics of patients of each group were observed and the effects of ovarian simulation and pregnancy outcomes were compared among the three groups. Logistic regression model was performed to explore the association between different groups and pregnancy outcomes. Results: The basic characteristics such as age, duration of infertility, body mass index (BMI) and serum basic follicle stimulating hormone (FSH) were comparable among the three groups (all P>0.05). Anti-Müllerian hormone (AMH), antral follicles count (AFC) and basic luteinized hormone (LH) were significantly lower in group C compared to group A and group B (all P<0.05). There were statistically significant differences in initiation dosage, total dosage and duration of gonadotropin (Gn) among the three groups (all P<0.01), the initiation dosage, total dosage and duration of Gn were higher in group C than the other two groups. The number of oocytes retrieved and available embryos were significantly lower in group B and group C than group A (all P<0.001). In fresh embryo transfer cycles, significantly higher implantation rate (45.3%, 117/258) and clinical pregnancy rate (52.6%, 111/211) were found for group C when compared with group A and group B (P=0.036, P=0.006). The live birth rate in fresh embryo transfer cycles was comparable among the three groups (P=0.098). The implantation rate, clinical pregnancy rate and live birth rate in the subsequent frozen-thawed embryo transfer cycles did not differ significantly among the three groups (all P>0.05). There were no significantly differences in the cumulative pregnancy rate and the cumulative live birth rate among the three groups (all P>0.05). After adjusted for age, BMI, AMH, AFC, basic FSH and LH, total Gn dosage, endometrial thickness at transfer, number of oocytes retrieved, number of embryos transferred and stage of embryo transferred, in fresh embryo transfer cycles, the clinical pregnancy rate (adjusted OR=2.793, 95%CI: 1.512-5.162, P<0.001) and live birth rate (adjusted OR=2.324, 95%CI: 1.241-4.351, P=0.008) were higher in group C, while clinical pregnancy rate and live birth rate were similar between group B and group A in fresh embryo transfer cycles (all P>0.05); there was no significant difference in cumulative live birth rate among the three groups (P>0.05). Conclusions: The supplementation of rLH from the first day of ovarian stimulation improves the pregnancy outcomes of patients at 35 years or older in fresh embryo transfer cycles during follicular-phase long protocol. However, the supplementation of rLH has no benefit on cumulative live birth rate.

Crosstalk between kisspeptin and gonadotropin-inhibitory hormone in the silence of puberty: preclinical evidence from a calcium signaling study.

Kisspeptin and gonadotropin-inhibitory hormone (GnIH) are among suggested neuroendocrine modulators of reproductive function. Intracellular calcium signaling is a critical component in the regulation of a variety of physiological and pathological processes including neurotransmitter release, and, therefore, can be used as signaling indicator for investigating the involvement of kisspeptin, GnIH, and gonadotropin-releasing hormone (GnRH) release. Hence, this study investigated the effects of kisspeptin and GnIH on calcium signaling using immortalized hypothalamic cells (rHypoE-8) as a model. Kisspeptin neurons were loaded with the ratiometric calcium dye (Fura-2 AM, 1 µmol) and intracellular free calcium ([Ca2+]i) responses were quantified using digital fluorescence imaging system. Kisspeptin-10 (100, 300, and 1000 nM) caused a significant increase in [Ca2+]i in rHypoE-8 cells (n = 58, n = 64, and n = 49, respectively, p < 0.001). The kisspeptin receptor antagonist, P234, inhibited the calcium responses to kisspeptin (p < 0.001, n = 32). GnIH (100 and 1000 nM), alone, did not cause any significant change in the mean basal [Ca2+]i levels in kisspeptin cells, but GnIH attenuated the kisspeptin-evoked [Ca2+]i transients (n = 47, p < 0.001). This novel findings of [Ca2+]i signaling in in vitro setting implicate that kisspeptin and GnIH may exert their effects on hypothalamus-pituitary-gonadal (HPG) axis by modulating kisspeptin neurons. These results also implicate that kisspeptin neurons may have an autocrine regulation.

Plasma Aromatase Activity Index, Gonadotropins and Estrone Are Associated with Frailty Syndrome in Post-Menopausal Women with Breast Cancer.

Frailty syndrome is associated with poor outcomes, morbidity and premature mortality. We performed a cross-sectional study to evaluate the presence of frailty syndrome based on Fried's frailty phenotype in post-menopausal women with breast cancer. We further analyzed the association between frailty syndrome with geriatric assessments and the association with the concentration of gonadotropins LH and FSH, estrogens, androgens and the aromatase activity index in the blood. We enrolled 47 post-menopausal women with localized breast cancer (mean age 66.8 ± 1.3 years (range 52−83)) prior to the starting of adjuvant endocrine therapy. Patients were identified as "non-frail" (robust) or "prefrail/frail" if they fulfilled at least one frailty criteria. In order to determine associations among variables and to control for other variables potentially affecting frailty syndrome (age, comorbidity index and previous chemotherapy treatment), we performed a logistic regression analysis. The receiver operating characteristic curve was performed to assess the sensitivity and specificity of the hormonal concentration to discriminate prefrail/frail versus non-frail individuals. Significant positive associations were observed between the severity of frailty syndrome and estrone, FSH and LH concentrations and the aromatase activity index in the blood (p < 0.05). Further research into the role of hormonal biomarkers should be evaluated in follow-up studies in order to recommend their use as suitable biomarkers of frailty syndrome in breast cancer patients.

Black coffee mitigates diethyl phthalate disrupted folliculogenesis, reduced gonadotropins, and ovarian lesions in female albino mice.

Phthalates are multifunctional compounds with extensive applications and emerging environmental pollutants. Due to their ubiquity in the environment and unavoidable exposure to humans, concerns have been voiced about public health dangers. This study was aimed to explore the diethyl phthalate (DEP) toxicity and the potential protective effect of black coffee in female Swiss albino mice. Four-week-old mice, weighing 12 ± 1 g were segregated into five groups (n = 10), designated as G-I (without any treatment), G-II (treated with corn oil), G-III (exposed to 1.5 mg/g body wt. (B.W.) DEP), G-IV (received 2 µg/g B.W coffee), and G-V (co-administrated with 1.5 mg/g DEP and 2 µg/g B.W coffee). Before dose administration, the coffee extract was assessed for its antioxidant potential through FRAP, TPC, and GC-MS analyses. Respective phthalates/coffee doses were administrated orally, once a day for 8 weeks consecutively starting from the prepubescent stage. After 56 days, mice were acclimated for 4 days then dissected. Morphological assessments showed an irregular shape of the ovaries in DEP-treated mice as compared to the control. The average bodyweight of DEP-intoxicated mice (p ≤ 0.05) increased notably against control, while DEP plus coffee group showed a regular gain in the average weight of mice. The gonado-somatic index showed non-significant variations among all groups. Micrometric studies showed that the diameter of secondary follicles (115 µm) in the ovaries of DEP-exposed mice (p ≤ 0.001) decreased significantly as compared to control (204 µm); conversely, follicular diameter in the coffee control group (248) increased significantly. Serum FSH and LH levels were significantly increased in DEP-exposed mice with a noteworthy decrease in estrogen level while hormonal levels of all other groups were comparable to control. Histological sections of DEP-exposed mice ovaries showed anatomical disruptions contrary to other groups, which were comparable with control. Antioxidant potential was checked in ovaries homogenates; FRAP values showed a notable decrease in DEP group in comparison with the control group, in contrast to G-V, when DEP was co-administrated with coffee. This study concluded that black coffee has protective effect, against DEP-instigated reproductive toxicity in Swiss albino female mice.

Gonadotropin-inhibitory hormone as a regulator of social interactions in vertebrates.

The social environment changes circulating hormone levels and expression of social behavior in animals. Social information is perceived by sensory systems, leading to cellular and molecular changes through neural processes. Peripheral reproductive hormone levels are regulated by activity in the hypothalamic-pituitary-gonadal (HPG) axis. Until the end of the last century, the neurochemical systems that convey social information to the HPG axis were not well understood. Gonadotropin-inhibitory hormone (GnIH) was the first hypothalamic neuropeptide shown to inhibit gonadotropin release, in 2000. GnIH is now regarded as a negative upstream regulator of the HPG axis, and it is becoming increasingly evident that it responds to social cues. In addition to controlling reproductive physiology, GnIH seems to modulate the reproductive behavior of animals. Here, we review studies investigating how GnIH neurons respond to social information and describe the mechanisms through which GnIH regulates social behavior.

Regulation of stress response on the hypothalamic-pituitary-gonadal axis via gonadotropin-inhibitory hormone.

Under stressful condition, reproductive function is impaired due to the activation of various components of the hypothalamic-pituitaryadrenal (HPA) axis, which can suppress the activity of the hypothalamic-pituitary-gonadal (HPG) axis at multiple levels. A hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH) is a key negative regulator of reproduction that governs the HPG axis. Converging lines of evidence have suggested that different stress types and their duration, such as physical or psychological, and acute or chronic, can modulate the GnIH system. To clarify the sensitivity and reactivity of the GnIH system in response to stress, we summarize and critically review the available studies that investigated the effects of various stressors, such as restraint, nutritional/metabolic and social stress, on GnIH expression and/or its neuronal activity leading to altered HPG action. In this review, we focus on GnIH as the potential novel mediator responsible for stress-induced reproductive dysfunction.

Ameliorative Potential of Hydroethanolic Leaf Extract of Parquetina nigrescens on d-Galactose-Induced Testicular Injury.

BACKGROUND: There is an increasing need for botanicals to be used as an alternative and complementary medicine in the management of male infertility. Male infertility has been a major health/social challenge to people all over the world. This study, therefore, investigated the ameliorative potential of hydroethanolic leaf extract of Parquetina nigrescens (HELEPN) against d-galactose-induced testicular injury. METHODS: Thirty male Wistar rats were randomly allotted into six groups (n = 5). Group I (Normal control), Group II (300 mg/kg b.w. d-galactose), Group III and IV (250 and 500 mg/kg b.w. HELEPN, respectively), Group V and VI (both received 300 mg/kg b.w. of d-galactose with 250 and 500 mg/kg b.w of HELEPN, respectively). d-galactose administration started two weeks prior to HELEPN treatment which lasted for six weeks. All assays were carried out using established protocols. RESULTS: Administration of HELEPN at 250mg/kg and 500mg/kg concomitantly with d-galactose improved paired and relative testicular weights, levels of gonadotropins (LH and FSH) and testosterone, and poor sperm quality. HELEPN treatment reduced the levels of oxidative stress biomarkers (MDA, 8-OHDG, and AGEs) and inflammatory response (TNF-alpha and NO) to normal, as well as restoring the reduced activities of antioxidant enzymes (glutathione peroxidase, superoxide dismutase, and catalase). In addition, HELEPN treatment mitigated testicular DNA fragmentation and down-regulated caspase 3-activities. HELEPN at 500 mg/kg was observed to have the greatest ameliorative effect. CONCLUSION: HELEPN protects against d-galactose-induced testicular injury through antioxidative, anti-inflammatory, and antiapoptotic mechanisms.

Safflower seed oil improves steroidogenesis and spermatogenesis in rats with type II diabetes mellitus by modulating the genes expression involved in steroidogenesis, inflammation and oxidative stress.

ETHNOPHARMACOLOGICAL RELEVANCE: Diabetes mellitus (DM), as a multiorgan syndrome, is an endocrine and metabolic disorder that is associated with male reproductive system dysfunction and infertility. Safflower (Carthamus tinctorius L.) as an herbal remedy improves DM and infertility-related disorders. The anti-hypercholesterolemic, anti-inflammatory, and antioxidative properties of this herb have been well documented, but its role in testosterone production, male reproductive system and zinc homeostasis has not been fully illustrated. AIM OF THE STUDY: This study aimed to investigate the preventive and therapeutic properties of different doses of safflower seed oil against reproductive damage caused by type II DM by investigating zinc element homeostasis, inflammation and oxidative damage in testis tissue and their relationship with testosterone production and sperm parameters. MATERIALS AND METHODS: Eighty adult male Sprague-Dawley rats were randomly divided into eight groups and treated daily for 12 and 24 weeks in protective and therapeutic studies, respectively. Type II DM was induced by a High Fat Diet (HFD) in normoglycemic rats for three months. At the end of each study, serum level of glucose, testosterone, gonadotropins, TNF-α, insulin, and leptin were measured. Moreover, antioxidant enzymes activity, lipid peroxidation, zinc and testosterone along with the expression of Nrf-2, NF-κB, TNF-α, StAR, P450scc, and 17ßHSD3 genes in the testis were detected. RESULTS: After the intervention, the activity of antioxidant enzymes and the level of testosterone and gonadotropins significantly decreased in the rats with DM in comparison to the others. However, lipid peroxidation and serum level of insulin, leptin and TNF-α increased and the testicular level of zinc significantly changed in the rats with DM compared to the control groups (p < 0.05). The gene expression of NF-κB and TNF-α were also significantly increased and the gene expression of Nrf2, StAR, P450scc and 17ßHSD3 were decreased in the testis of diabetic rats (p < 0.05). The results showed that pretreatment and treatment with safflower seed oil could improve these parameters in diabetic rats compared with untreated diabetic rats (p < 0.05). CONCLUSION: HFD could impair the production of testosterone and sperm, and reduce gonadotropin by increasing the serum level of leptin and inducing insulin resistance, oxidative stress and inflammation. However, safflower oil in a dose-dependent manner could improve testosterone level and sperm parameters by improving the level of leptin, zinc and insulin resistance, and the genes expression involved in testosterone synthesis, inflammation and oxidative stress.

RF-amide related peptide-3 (RFRP-3): a novel neuroendocrine regulator of energy homeostasis, metabolism, and reproduction.

A hypothalamic neuropeptide, RF-amide related peptide-3 (RFRP-3), the mammalian ortholog of the avian gonadotropin-inhibitory hormone (GnIH) has inhibitory signals for reproductive axis via G-protein coupled receptor 147 in mammals. Moreover, RFRP-3 has orexigenic action but the mechanism involved in energy homeostasis and glucose metabolism is not yet known. Though, the RFRP-3 modulates orexigenic action in co-operation with other neuropeptides, which regulates metabolic cues in the hypothalamus. Administration of GnIH/RFRP-3 suppresses plasma luteinizing hormone, at the same time stimulates feeding behavior in birds and mammals. Likewise, in the metabolically deficient conditions, its expression is up-regulated suggests that RFRP-3 contributes to the integration of energy balance and reproduction. However, in many other metabolic conditions like induced diabetes and high-fat diet obesity, etc. its role is still not clear while, RFRP-3 induces the glucose homeostasis by adipocytes is reported. The physiological role of RFRP-3 in metabolic homeostasis and the metabolic effects of RFRP-3 signaling in pharmacological studies need a detailed discussion. Further studies are required to find out whether RFRP-3 is associated with restricted neuroendocrine function observed in type II diabetes mellitus, aging, or sub-fertility. In this context, the current review is focused on the role of RFRP-3 in the above-mentioned mechanisms. Studies from search engines including PubMed, Google Scholar, and science.gov are included after following set inclusion/exclusion criteria. As a developing field few mechanisms are still inconclusive, however, based on the available information RFRP-3 seems to be a putative tool in future treatment strategies towards metabolic disease.

Testicular Atrophy and Hypothalamic Pathology in COVID-19: Possibility of the Incidence of Male Infertility and HPG Axis Abnormalities.

Coronavirus disease 2019 (COVID-19), which resulted from the pandemic outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), causes a massive inflammatory cytokine storm leading to multi-organ damage including that of the brain and testes. While the lungs, heart, and brain are identified as the main targets of SARS-CoV-2-mediated pathogenesis, reports on its testicular infections have been a subject of debate. The brain and testes are physiologically synchronized by the action of gonadotropins and sex steroid hormones. Though the evidence for the presence of the viral particles in the testicular biopsies and semen samples from COVID-19 patients are highly limited, the occurrence of testicular pathology due to abrupt inflammatory responses and hyperthermia has incresingly been evident. The reduced level of testosterone production in COVID-19 is associated with altered secretion of gonadotropins. Moreover, hypothalamic pathology which results from SARS-CoV-2 infection of the brain is also evident in COVID-19 cases. This article revisits and supports the key reports on testicular abnormalities and pathological signatures in the hypothalamus of COVID-19 patients and emphasizes that testicular pathology resulting from inflammation and oxidative stress might lead to infertility in a significant portion of COVID-19 survivors. Further investigations are required to monitor the reproductive health parameters and HPG axis abnormalities related to secondary pathological complications in COVID-19 patients and survivors.

Gonadotropin-inhibitory hormone (GnIH): A new key neurohormone controlling reproductive physiology and behavior.

The discovery of novel neurohormones is important for the advancement of neuroendocrinology. In early 1970s, gonadotropin-releasing hormone (GnRH), a hypothalamic neuropeptide that promotes gonadotropin release, was identified to be an endogenous neurohormone in mammals. In 2000, thirty years later, another hypothalamic neuropeptide, gonadotropin-inhibitory hormone (GnIH), that inhibits gonadotropin release, was found in quail. GnIH acts via GPR147 and inhibits gonadotropin release and synthesis and reproductive function in birds through actions on GnRH neurons in the hypothalamus and pituitary gonadotrophs. Later, GnIH was found in other vertebrates including humans. GnIH studies have advanced the progress of reproductive neuroendocrinology. Furthermore, recent GnIH studies have indicated that abnormal changes in GnIH expression may cause pubertal disorder and reproductive dysfunction. Here, we describe GnIH discovery and its impact on the progress of reproductive neuroendocrinology. This review also highlights advancement and perspective of GnIH studies on drug development for pubertal disorder and reproductive dysfunction. (149/150).

Xylopia aethiopica ethanol seed extract suppresses Cadmium chloride-induced ovary and gonadotropins toxicity in adult female Wistar rats.

OBJECTIVE: Xylopia aethiopica is a common plant in West Africa, with wide applications in trado-medical management of several diseases. Thus, our study aimed to analyze the histology and hormonal effects of ethanol extracts of Xylopia aethiopica seeds on cadmium chloride-induced reproductive dysfunction in female Wistar rats. METHODS: We used twenty-five rats weighing 120-150g for this study. The rats were divided into five groups (n=5). Group 1: received only distilled water orally; Group 2: received 2 mg/kg cadmium chloride orally; Group 3: received 2 mg/kg cadmium chloride plus 50 mg/kg Xylopia aethiopica seeds orally; Group 4: received 2 mg/kg cadmium chloride plus 100 mg/kg Xylopia aethiopica seeds orally, and Group 5: received 100 mg/kg Xylopia aethiopica seeds only, orally. We administered the extracts for 14 days, after which we slaughtered the animals following chloroform anesthesia. We took the blood samples by cardiac puncture for hormonal assay. The ovaries and uterus were harvested for histology. We analyzed the data using ANOVA, and the differences in mean values were considered significant at p<0.05. RESULTS: The body weight of the rats showed a dose-dependent reduction (p<0.05), compared with the controls. Xylopia aethiopica seeds significantly (p<0.05) reversed the detrimental effects of Cadmium on LH and FSH. The histological analysis of the ovary showed significant improvement upon treatment with Xylopia aethiopica extract in a dose-dependent manner. CONCLUSIONS: The ameliorative effects of Xylopia aethiopica against cadmium chloride-induced reproductive toxicity in female Wistar rats may be attributed to its antioxidant properties.

Chronic effects of maternal tobacco-smoke exposure and/or α-lipoic acid treatment on reproductive parameters in female rat offspring.

Prenatal tobacco-smoke exposure negatively affects the reproductive functions of female offspring and oxidative stress plays a major role at this point. Alpha-lipoic acid (ALA), well known as a biological antioxidant, has been used as a nutritional supplement and as a therapeutic agent in the treatment of certain complications during pregnancy. We aimed to investigate the effects of maternal tobacco-smoke exposure and/or ALA administration on puberty onset, sexual behavior, gonadotrophin levels, apoptosis-related genes, apoptotic cell numbers and oxidative stress markers in the adult female rat offspring. Sprague-Dawley rats were divided into four groups; control, tobacco smoke (TS), TS+ALA and ALA groups. Animals were exposed to TS and/or ALA for 8 weeks before pregnancy and throughout pregnancy. All treatments ended with birth and later newborn female rats were selected for each experimental group. The experiment ended at postnatal day 74-77. Maternal tobacco smoke advanced the onset of puberty in the female offspring of the TS group (p < 0.05). In all treatment groups; the mean number of anogenital investigations and lordosis quality scores showed a decline, serum luteinizing hormone levels significantly increased (p < 0.05) and several histopathological changes in ovaries were observed compared to the control group. In addition, an increase in apoptotic marker levels and apoptotic cell numbers was detected in the ovaries of all treatment groups. Decreased TAS and increased TOS levels were detected in all treatment groups compared to control. These findings suggested that maternal tobacco smoke and/or ALA administration may be leading to the impaired reproductive health of female offspring. Abbreviations: ALA: alpha-lipoic acid; LH: luteinizing hormone; FSH: follicle-stimulating hormone; TAS: total antioxidant status; TOS: total oxidant status; Apaf1: apoptotic protease-activating factor 1; Casp3: caspase 3; Casp9: caspase 9; CF: cyst follicles; 4-HNE: 4-Hidroxynonenal; 8-OHdG: 8-hydroxydeoxyguanosine; TUNEL: terminal deoxynucleotidyl transferase-mediated deoxyuridine-biotin nick end labeling; ROS: reactive oxygen species; GnRHR: gonadotropin-releasing hormone receptor; HPG: hypothalamic-pituitary-gonadal; AMPK: AMP-activated protein kinase; ELISA: enzyme-linked immunosorbent assay; cDNA: complementary DNA; qPCR: quantitative real-time PCR; FC: follicular cysts; PF: primary follicle; SF: secondary follicle; GF: graafian follicle; CL: corpus luteum; DF: degenerated follicle; AF: atretic follicle.