RESUMO
This study evaluated whether the treatment of pseudopregnancy in bitches with vitamin B6 modulates uterine expression of receptors for progesterone (PR), oestrogen (ERα), androgen (AR), thyroid hormone (TRα) and the kisspeptin/Kiss1r system. Eighteen pseudopregnant bitches were treated for 20 days in groups receiving placebo (n = 6); cabergoline (5 µg/kg/day; n = 6); or vitamin B6 (50 mg/kg/day; n = 6). Blood was collected on the 1st day of drug administration and 120 h later to measure serum prolactin (PRL). After treatment, they were ovariohysterectomized and uterine fragments were collected for histomorphometry and immunohistochemical evaluation of PR, ERα, AR, TRα, Kiss1 and Kiss1r. After 120 h of cabergoline or vitamin B6 treatment, PRL levels were reduced in the bitches, confirming the antiprolactinemic effect of these drugs. Furthermore, regardless of treatment, the animals exhibited uterine histomorphometry consistent with dioestrus. The PR showed strong immunostaining in all regions and an increase in scores was observed for this receptor in animals treated with vitamin B6 in deep glands. In contrast, ERα and Kiss1R receptors showed weak to no immunostaining in all uterine regions and no changes between groups. Regarding AR, most animals treated with vitamin B6 showed increased trends in the deep gland and myometrium marking scores. In contrast, in both vitamin B6 and cabergoline treatments, a reduction in TRα marking scores was observed compared to the control group. In addition, on the endometrial surface, a reduction was observed in the marked area of Kiss1 after administration of cabergoline when compared to the pseudopregnant control group. These findings shed valuable insight into the use of vitamin B6 as a drug with actions similar to cabergoline in reducing PRL and uterine modulation in bitches.
Assuntos
Cabergolina , Kisspeptinas , Prolactina , Pseudogravidez , Útero , Animais , Feminino , Cães , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Útero/efeitos dos fármacos , Útero/metabolismo , Cabergolina/farmacologia , Prolactina/metabolismo , Pseudogravidez/veterinária , Pseudogravidez/metabolismo , Receptores de Progesterona/metabolismo , Receptores Androgênicos/metabolismo , Ergolinas/farmacologiaRESUMO
The effect of a synthetic analog of kisspeptin 1, a peptide involved in the regulation of the hypothalamicpituitary- gonadal (HPG) stress axis, on the cortisol level of Danio rerio fish was investigated. Kisspeptin 1 was administered at doses of 2 µg/kg and 8 µg/kg followed by resting for 1 h and 4 h. We found that kisspeptin at doses of 2 µg/kg and 8 µg/kg increased cortisol levels, with a significant spike in cortisol levels at 1 h post-injection.
Assuntos
Hidrocortisona , Kisspeptinas , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Masculino , FemininoRESUMO
The neuropeptide kisspeptin (Kiss) is crucial in regulating the hypothalamic-pituitary-gonadal axis. It is produced by two main groups of neurons in the hypothalamus: the rostral periventricular region around the third ventricle and the arcuate nucleus. Kiss is the peptide product of the KiSS-1 gene and serves as the endogenous agonist for the GPR54 receptor. The Kiss/GPR54 system functions as a critical regulator of the reproductive system. Thus, we examined the effect of intracerebroventricular administration of 3 µg of Kiss to the right lateral ventricle of ovariectomized rats primed with a dose of 5 µg subcutaneous (sc) of estradiol benzoate (EB). Kiss treatment increased the lordosis quotient at all times tested. However, the lordosis reflex score was comparatively lower yet still significant compared to the control group. To investigate receptor specificity and downstream mechanisms on lordosis, we infused 10 µg of GPR54 receptor antagonist, Kiss-234, 5 µg of the progestin receptor antagonist, RU486, or 3 µg of antide, a gonadotropin-releasing hormone-1 (GnRH-1) receptor antagonist, to the right lateral ventricle 30 min before an infusion of 3 µg of Kiss. Results demonstrated a significant reduction in the facilitation of lordosis behavior by Kiss at 60 and 120 min when Kiss-234, RU486, or antide were administered. These findings suggest that Kiss stimulates lordosis expression by activating GPR54 receptors on GnRH neurons and that Kiss/GPR54 system is an essential intermediary by which progesterone activates GnRH.
Assuntos
Estradiol , Kisspeptinas , Receptores LHRH , Receptores de Progesterona , Comportamento Sexual Animal , Animais , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Feminino , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Receptores LHRH/antagonistas & inibidores , Receptores LHRH/metabolismo , Ratos , Estradiol/farmacologia , Estradiol/análogos & derivados , Receptores de Progesterona/metabolismo , Receptores de Progesterona/efeitos dos fármacos , Receptores de Progesterona/antagonistas & inibidores , Ovariectomia , Ratos Wistar , Progesterona/farmacologia , Antagonistas de Hormônios/farmacologia , Postura/fisiologia , Receptores de Kisspeptina-1/metabolismo , Mifepristona/farmacologiaRESUMO
This study explored the alteration in kisspeptin and reproductive hormones during different superovulation protocols (SOP) in dromedary camel. The kisspeptin and reproductive hormonal profile, ovarian response, and the quality and quantity of embryos in dromedary camel donors were evaluated. A total of thirty donor camels were divided into two groups: the 5dSOP group, which received diluent containing 400 mg pFSH dissolved in 20 ml and administered two times daily for 5 days at decreasing doses (2.5, 2, 1.5, and 1 ml); and the 3dSOP group, which received diluent containing 400 mg pFSH dissolved in 12 ml and administered two times daily for 3 days at decreasing doses (3 ml, 2 ml, and 1 ml). Ultrasonography was used to monitor the ovarian environment, recording daily follicle count and dimensions and the time taken for follicles to mature. On the sixth day after mating, a corpus luteum (CL) count was conducted. On the 8th day after mating, records of the quantity and quality of embryos collected were kept. Blood samples from the jugular vein were collected at the commencement of the superovulation protocol and at 8:00 a.m. for the following 48 h to measure the concentrations of follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), kisspeptin (KP), and progesterone (P4). The findings indicated that the 3dSOP yielded superior results compared to the 5dSOP in terms of follicle quantity and size, as well as the quantity of CL and embryos. This improvement was attributed to significantly higher concentrations of reproductive hormones, including FSH, LH, E2, kisspeptin, and P4 (P ≤ 0.05), in the 3dSOP than in the 5dSOP. In conclusion, reducing the duration of superovulation protocols contributed to the proliferation of follicles with improved dimensions and counts, ultimately resulting in a greater quantity of embryos of superior quality. The levels of FSH, LH, E2, KP, and P4 were affected significantly by SOP and time of evaluation.
Assuntos
Camelus , Hormônio Foliculoestimulante , Kisspeptinas , Progesterona , Superovulação , Animais , Camelus/fisiologia , Superovulação/efeitos dos fármacos , Feminino , Kisspeptinas/farmacologia , Kisspeptinas/administração & dosagem , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/farmacologia , Progesterona/sangue , Estradiol/sangue , Folículo Ovariano/efeitos dos fármacos , Hormônio Luteinizante/sangue , OvárioRESUMO
Epigenetic alterations my play a role in the aggressive behavior of Non-Small Cell Lung Cancer (NSCLC). Treatment with the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA, vorinostat) has been reported to interfere with the proliferative and invasive potential of NSCLC cells. In addition, the DNA methyltransferase inhibitor azacytidine (AZA, vidaza) can modulate the levels of the metastasis suppressor KiSS-1. Thus, since cisplatin is still clinically available for NSCLC therapy, the aim of this study was to evaluate drug combinations between cisplatin and SAHA as well as AZA using cisplatin-sensitive H460 and -resistant H460/Pt NSCLC cells in relation to KiSS-1 modulation. An analysis of drug interaction according to the Combination-Index values indicated a more marked synergistic effect when the exposure to SAHA or AZA preceded cisplatin treatment with respect to a simultaneous schedule. A modulation of proteins involved in apoptosis (p53, Bax) was found in both sensitive and resistant cells, and compared to the treatment with epigenetic agents alone, the combination of cisplatin and SAHA or AZA increased apoptosis induction. The epigenetic treatments, both as single agents and in combination, increased the release of KiSS-1. Finally, the exposure of cisplatin-sensitive and -resistant cells to the kisspeptin KP10 enhanced cisplatin induced cell death. The efficacy of the combination of SAHA and cisplatin was tested in vivo after subcutaneous inoculum of parental and resistant cells in immunodeficient mice. A significant tumor volume inhibition was found when mice bearing advanced tumors were treated with the combination of SAHA and cisplatin according to the best schedule identified in cellular studies. These results, together with the available literature, support that epigenetic drugs are amenable for the combination treatment of NSCLC, including patients bearing cisplatin-resistant tumors.
Assuntos
Azacitidina , Cisplatino , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Kisspeptinas , Neoplasias Pulmonares , Vorinostat , Cisplatino/farmacologia , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Humanos , Camundongos , Epigênese Genética/efeitos dos fármacos , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Kisspeptinas/genética , Linhagem Celular Tumoral , Vorinostat/farmacologia , Azacitidina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores de Histona Desacetilases/farmacologia , FemininoRESUMO
Parkinson's Disease is a progressive neurodegenerative disorder characterized by motor symptoms resulting from the loss of nigrostriatal dopaminergic neurons. Kisspeptins (KPs) are a family of neuropeptides that are encoded by the Kiss-1 gene, which exert their physiological effects through interaction with the GPR54 receptor. In the current investigation, we investigated the prospective protective effects of central KP-54 treatments on nigrostriatal dopaminergic neurons and consequent motor performance correlates in 6-hydroxydopamine (6-OHDA)-lesioned rats. Male adult Sprague Dawley rats underwent stereotaxic injection of 6-OHDA into the right medial forebrain bundle to induce hemiparkinsonism. Following surgery, rats received chronic central treatments of nasal or intracerebroventricular KP-54 (logarithmically increasing doses) for seven consecutive days. Motor performance was evaluated seven days post-surgery utilizing the open field test and catalepsy test. The levels of dopamine in the striatum were determined with mass spectrometry. Immunohistochemical analysis was conducted to assess the immunoreactivities of tyrosine hydroxylase (TH) and the GPR54 in the substantia nigra. The dose-response curve revealed a median effective dose value of ≈3 nmol/kg for both central injections. Due to its non-invasive and effective nature, nasal administration was utilized in the second phase of our study. Chronic administration of KP-54 (3nmol/kg, nasally) significantly protected 6-OHDA-induced motor deficits. Nasal KP-54 attenuated the loss of nigrostriatal dopaminergic neurons induced by 6-OHDA. Additionally, significant correlations were observed between motor performance and nigrostriatal dopamine levels. Immunohistochemical analysis demonstrated the localization of the GPR54 within TH-positive nigral cells. These findings suggest the potential efficacy of central KP-54 on motor impairments in hemiparkinsonism.
Assuntos
Administração Intranasal , Corpo Estriado , Dopamina , Neurônios Dopaminérgicos , Kisspeptinas , Oxidopamina , Transtornos Parkinsonianos , Ratos Sprague-Dawley , Substância Negra , Animais , Masculino , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Dopamina/metabolismo , Oxidopamina/farmacologia , Ratos , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Kisspeptinas/administração & dosagem , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Modelos Animais de Doenças , Atividade Motora/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismoRESUMO
Kisspeptin is an important hormone involved in the stimulation of the hypothalamo-pituitary gonadal (HPG) axis. The HPG axis can be suppressed in certain conditions such as stress, which gives rise to the activation of the hypothalamo-pituitary-adrenal (HPA) axis. However, the physiological role of kisspeptin in the interaction of HPG and HPA axis is not fully understood yet. This study was conducted to investigate the possible effects of central kisspeptin injection on HPG axis as well as HPA axis activity. Adult male Wistar rats were randomly divided into seven groups as followed: sham (control), kisspeptin (50 pmol), P234 (1 nmol), kisspeptin + p234, kisspeptin + antalarmin (0.1 µg), kisspeptin + astressin 2B (1 µg), and kisspeptin + atosiban (300 ng/rat) (n = 10 each group). At the end of the experiments, the hypothalamus, pituitary, and serum samples of the rats were collected. There was no significant difference in corticotropic-releasing hormone immunoreactivity in the paraventricular nucleus of the hypothalamus, serum adrenocorticotropic hormone, and corticosterone levels among all groups. Moreover, no significant difference was detected in pituitary oxytocin level. Serum follicle-stimulating hormone and luteinizing hormone levels of the kisspeptin, kisspeptin + antalarmin, and kisspeptin + astressin 2B groups were significantly higher than the control group. Serum testosterone levels were significantly higher in the kisspeptin kisspeptin + antalarmin, kisspeptin + astressin 2B, and kisspeptin + atosiban groups compared to the control group. Our findings suggest that central kisspeptin injection causes activation in the HPG axis, but not the HPA axis in male rats.
Assuntos
Sistema Hipotálamo-Hipofisário , Kisspeptinas , Sistema Hipófise-Suprarrenal , Ratos Wistar , Animais , Masculino , Kisspeptinas/administração & dosagem , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Fragmentos de Peptídeos/administração & dosagem , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Corticosterona/sangue , Vasotocina/farmacologia , Vasotocina/administração & dosagem , Testosterona/sangue , Injeções Intraventriculares , Gônadas/metabolismo , Gônadas/efeitos dos fármacos , Hipófise/metabolismo , Hipófise/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/metabolismo , Hormônio Adrenocorticotrópico/sangue , Hormônio Liberador da Corticotropina , OligopeptídeosRESUMO
Kisspeptin is a peptide that plays an important role through its effects on the hypothalamus-pituitary-gonadal (HPG) axis. It has also been implicated in sexual behavior. The present study investigated whether the relationship between kisspeptin and sexual behavior is independent of the HPG axis, i.e., testosterone. Sexual behavior was examined after the administration of kisspeptin to gonadally intact male rats and gonadectomized male rats that received testosterone supplementation. Other male rats were also observed for sexual behavior once a week from 2 to 5 weeks after gonadectomy and receiving kisspeptin for the sixth postoperative week. Sexual behavior in female rats serving as the partner for each male was also observed. Female rats were not administered kisspeptin in the present study. The results obtained showed that the administration of kisspeptin increased precopulatory behavior in gonadally intact male rats and gonadectomized male rats that received testosterone supplementation and proceptive behavior in their female partners. Precopulatory behavior in males and receptive behavior in females increased, while copulatory behavior in males and receptive behavior in females remained unchanged. Furthermore, the administration of kisspeptin increased precopulatory behavior in gonadectomized males, but did not affect receptive behavior in females. These results suggest that kisspeptin affected males independently and/or supplementally to testosterone, and also that changes in the presence of testosterone in males had an impact on proceptive behavior in their female partners. In conclusion, kisspeptin may involve an as-yet-unidentified neural pathway in sexual desire independently of the HPG axis.
Assuntos
Kisspeptinas , Comportamento Sexual Animal , Testosterona , Animais , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Masculino , Testosterona/farmacologia , Feminino , Ratos , Comportamento Sexual Animal/efeitos dos fármacos , Comportamento Sexual Animal/fisiologia , Ratos Wistar , Copulação/efeitos dos fármacos , Copulação/fisiologiaRESUMO
The presence of Kisspeptin (Kp) and its receptors in the corpus luteum (CL) of buffalo has recently been demonstrated. In this study, we investigated the role of Kp in the modulation of progesterone (P4) synthesis in vitro. The primary culture of bubaline luteal cells (LCs) was treated with 10, 50, and 100 nM of Kp and Kp antagonist (KpA) alongside a vehicle control. The combined effect of Kp and KpA was assessed at 100 nM concentration. Intracellular response to Kp treatment in the LCs was assessed by examining transcript profiles (LHR, STAR, CYP11A1, HSD3B1, and ERK1/2) using quantitative polymerase chain reaction (qPCR). In addition, the immunolocalization of ERK1/2 and phosphorylated ERK1/2 (p-ERK1/2) in the LCs was studied using immunocytochemistry. Accumulation of P4 from the culture supernatant was determined using enzyme-linked immunosorbent assay (ELISA). The results indicated that LCs had a greater p-ERK1/2 expression in the Kp treatment groups. A significant increase in the P4 concentration was recorded at 50 nM and 100 nM Kp, while KpA did not affect the basal concentration of P4. However, the addition of KpA to the Kp-treated group at 100 nM concentration suppressed the Kp-induced P4 accumulation into a concentration similar to the control. There was significant upregulation of ERK1/2 and CYP11A1 expressions in the Kp-treated LCs at 100 nM (18.1 and 37fold, respectively, p < 0.01). However, the addition of KpA to Kp-treated LCs modulated ERK1/2, LHR, STAR, CYP11A1, and HSD3B1 at 100 nM concentration. It can be concluded that Kp at 100 nM stimulated P4 production, while the addition of KpA suppressed Kp-induced P4 production in the buffalo LCs culture. Furthermore, an increment in p-ERK1/2 expression in the LCs indicated activation of the Kp signaling pathway was associated with luteal steroidogenesis.
Assuntos
Células Lúteas , Feminino , Animais , Progesterona/metabolismo , Kisspeptinas/genética , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Regulação para Cima , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Sistema de Sinalização das MAP Quinases , Corpo Lúteo/fisiologia , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismoRESUMO
Kisspeptin is a multifunctional neurohormone, primarily involved in the regulation of reproduction. We tested whether peripheral administration of kisspeptin10 (KP-10) via intraperitoneal injection or slow release affects reproductive hormones and metabolites in Sterlet sturgeon (Acipenser ruthenus). Plasma and mucus 17ß-estradiol (E2), and testosterone (T), plasma and follicular vitellogenin (VTG) and calcium (Ca) as well as glucose and lipids were determined. Mature Sterlet sturgeon were grouped into six groups: saline i.p injection (control), human kisspeptin (hKP-10) i.p injection; acipenser kisspeptin (aKP-10) i.p injection; hKP-10 (slow release); aKP-10 (slow-release) and no treatment control. No effect for KP-10 on sturgeon body weight was found after 4 weeks of treatment. Multivariate analysis revealed a significant disparity in plasma E2 levels. It was significantly different between groups (time, P = 0.0022). E2 in epithelia mucosa showed significant difference between and within groups in the acute group (time, P = 0.0252; treatment, P = 0.0423; time × treatment, P = 0.0429). T levels were unaffected by treatments (P > 0.05). The presence of synthetic aKP-10 led to an elevation in oocyte and plasma VTG levels (P < 0.05). Prolonged exposure to this peptide resulted in an increase in plasma calcium levels. Simultaneously, there was an augmentation in the number of mature follicles. Regardless of the duration of exposure, aKP-10 significantly elevated plasma glucose levels in Sterlet (P < 0.0). Additionally, KP-10 led to an increase in plasma lipids and cholesterol in Sterlet. Overall, our data support an involvement for KP-10 in the regulation of gonadal steroid hormones, oocyte maturation and metabolite levels in sturgeon, suggesting a positive role for this peptide in the reproductive physiology of this species.
Assuntos
Cálcio , Kisspeptinas , Feminino , Humanos , Animais , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Cálcio/metabolismo , Injeções Intraperitoneais , Peixes/fisiologia , Estradiol/metabolismo , Colesterol/metabolismoRESUMO
SCOPE: The disturbance of the hypothalamic-pituitary-gonadal (HPG) axis, gut microbiota (GM) community, and short-chain fatty acids (SCFAs) is a triggering factor for pubertal onset. The study investigates the effects of the long-term intake of aspartame on puberty and GM in animals and humans. METHODS AND RESULTS: Aspartame-fed female offspring rats result in vaginal opening time prolongation, serum estrogen reduction, and serum luteinizing hormone elevation. , 60 mg kg-1 aspartame treatment decreases the mRNA levels of gonadotropin-releasing hormone (GnRH), Kiss1, and G protein-coupled receptor 54 (GPR54), increases the mRNA level of RFamide-related peptide-3 (RFRP-3), and decreases the expression of GnRH neurons in the hypothalamus. Significant differences in relative bacterial abundance at the genus levels and decreased fecal SCFA levels are noted by 60 mg kg-1 aspartame treatment. Among which, Escherichia-Shigella is negatively correlated with several SCFAs. In girls, high-dose aspartame consumption decreases the risk of precocious puberty. CONCLUSIONS: Aspartame reduces the chance of puberty occurring earlier than usual in female offspring and girls. Particularly, 60 mg kg-1 aspartame-fed female offspring delays pubertal onset through the dysregulation of HPG axis and GM composition by inhibiting the Kiss1/GPR54 system and inducing the RFRP-3. An acceptable dose of aspartame should be recommended during childhood.
Assuntos
Kisspeptinas , Puberdade Tardia , Humanos , Ratos , Feminino , Animais , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Aspartame/efeitos adversos , Aspartame/metabolismo , Puberdade Tardia/metabolismo , Ratos Sprague-Dawley , Maturidade Sexual/fisiologia , Hormônio Liberador de Gonadotropina/genética , Hipotálamo/metabolismo , Puberdade , RNA Mensageiro/metabolismoRESUMO
OBJECTIVE: To elucidate the mechanism of the nourishing Yin and purging fire Chinese herbal mixture (NYPF) in delaying light-induced premature puberty in rats. METHODS: Twenty-one days old female Sprague-Dawley rats were randomly assigned to normal group (N), long light exposure group (L), NYPF and normal saline group (NS). Rats in the L, NYPF and NS groups were exposed to 16 h: 350 lux light/8 h: dark, while rats in the N group were exposed to 12 h: 50 lux light/12 h: dark. NYPF and normal saline was administered to the rats in the NYPF group or NS group, respectively, from day 21. Five rats in every group were sacrificed at 9 p.m. on day 28 (P28), on the day when rat's vulva opened in the L group (L-VO), on the day when the first estrous interphase occurred in rats of L group (L-E1), and on the day when the second estrous interphase occurred in rats of L group (L-E2), respectively. RESULITS: On day 34, all rats in the L group, 80% of rats in the NS group, 40% of rats in the N group, and 20% of rats in the NYPF group showed complete opening of the vulva. At P28, mRNA level of hypothalamic kisspeptin (Kiss-1) in the L group was significantly higher than that in the N group (P < 0.05). The rats in the L and NS groups had significantly lower hypothalamic arginine-phenylalanine-amide (RFamide)-related peptide 3 (RFRP-3) mRNA levels than those in the N group (P < 0.05), whereas RFRP-3 mRNA level was significantly higher in the NYPF group than that in the L group (P < 0.05). At L-VO, the ovarian index of the L and NS groups was significantly higher than that of the N group (P < 0.05) and estradiol (E2) level of the NYPF group was significantly lower than that of the N and NS groups (P < 0.05); hypothalamic Kiss-1 mRNA level in the L and NS groups was significantly higher than that in the N and NYPF groups (P < 0.05), whereas hypothalamic RFRP-3 mRNA level in the L, NYPF, and NS groups was significantly lower than that in the N group (P < 0.05). At L-E1, E2 level of the L and NS groups was significantly higher than that of the N group (P < 0.01), whereas it was significantly lower in the NYPF group than that of the N, L, and NS groups (P < 0.01), and serum luteinizing hormone level of the L and NS groups was significantly higher than that of the N group (P < 0.05); levels of serum melatonin and ovarian melatonin receptor 1 (MT-1) mRNA in the L, NYPF, and NS groups were significantly lower than those in the N group (P < 0.05). At L-E2, the uterine organ index of the NYPF group was significantly lower than that of the L group (P < 0.05); and ovarian MT-1 mRNA level of the L and NS groups was significantly lower than that in the N group (P < 0.05). CONCLUSIONS: NYPF can delay puberty onset in rats exposed to strong light for a prolonged duration, and regulation of the gene expression of Kiss-1 and RFRP-3 in the hypothalamus has been suggested as one of the mechanisms.
Assuntos
Kisspeptinas , Solução Salina , Ratos , Animais , Feminino , Ratos Sprague-Dawley , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Solução Salina/metabolismo , Solução Salina/farmacologia , Maturidade Sexual , Hipotálamo/metabolismo , RNA Mensageiro/metabolismoRESUMO
BACKGROUND: Kisspeptin is an essential regulator of hypothalamic gonadotropin-releasing hormone release and is required for physiological ovulation. Native kisspeptin-54 can induce oocyte maturation during in vitro fertilization treatment, including in women who are at high risk of ovarian hyperstimulation syndrome. MVT-602 is a potent kisspeptin receptor agonist with prospective utility to treat anovulatory disorders by triggering oocyte maturation and ovulation during medically assisted reproduction (MAR). Currently, the endocrine profile of MVT-602 during ovarian stimulation is unreported. OBJECTIVE: To determine the endocrine profile of MVT-602 in the follicular phase of healthy premenopausal women (phase-1 trial), and after minimal ovarian stimulation to more closely reflect the endocrine milieu encountered during MAR (phase-2a trial). DESIGN: Two randomized, placebo-controlled, parallel-group, dose-finding trials. SETTING: Clinical trials unit. PATIENTS: Healthy women aged 18-35 years, either without (phase-1; n = 24), or with ovarian stimulation (phase-2a; n = 75). INTERVENTIONS: Phase-1: single subcutaneous dose of MVT-602 (0.3, 1.0, or 3.0 µg) or placebo, (n = 6 per dose). Phase-2a: single subcutaneous dose of MVT-602 (0.1, 0.3, 1.0, or 3.0 µg; n = 16-17 per dose), triptorelin 0.2 mg (n = 5; active comparator), or placebo (n = 5). MAIN OUTCOME MEASURES: Phase-1: safety/tolerability; pharmacokinetics; and pharmacodynamics (luteinizing hormone [LH] and other reproductive hormones). Phase-2a: safety/tolerability; pharmacokinetics; pharmacodynamics (LH and other reproductive hormones); and time to ovulation assessed by transvaginal ultrasound. RESULTS: In both the trials, MVT-602 was safe and well tolerated across the entire dose range. It was rapidly absorbed and eliminated, with a mean elimination half-life of 1.3-2.2 hours. In the phase-2a trial, LH concentrations increased dose dependently; mean maximum change from baseline of 82.4 IU/L at 24.8 hours was observed after administration of 3 µg MVT-602 and remained >15 IU/L for 33 hours. Time to ovulation after drug administration was 3.3-3.9 days (MVT-602), 3.4 days (triptorelin), and 5.5 days (placebo). Ovulation occurred within 5 days of administration in 100% (3 µg), 88% (1 µg), 82% (0.3 µg), and 75% (0.1 µg), of women after MVT-602, 100% after triptorelin and 60% after placebo. CONCLUSIONS: MVT-602 induces LH concentrations of similar amplitude and duration as the physiological midcycle LH surge with potential utility for induction of oocyte maturation and ovulation during MAR. CLINICAL TRIAL REGISTRATION NUMBER: EUDRA-CT: 2017-003812-38, 2018-001379-20.
Assuntos
Kisspeptinas , Pamoato de Triptorrelina , Feminino , Humanos , Fertilização in vitro/métodos , Hormônio Liberador de Gonadotropina/agonistas , Kisspeptinas/farmacologia , Hormônio Luteinizante , Indução da Ovulação/métodos , Adolescente , Adulto Jovem , AdultoRESUMO
This study evaluated the effects of Cl3BPA on kisspeptin-G-protein coupled receptor 54 (GPR54)/gonadotropin-releasing hormone (GnRH) (KGG) signals and analyzed the roles of estrogen receptor alpha (ERÉ) and G-protein coupled estrogen receptor 1 (GPER1) in regulating KGG signals. The results showed that Cl3BPA at 50 µM increased the levels of intracellular reactive oxygen species (ROS) and GnRH, upregulated the protein levels of kisspeptin and the expression of fshr, lhr and gnrh1 genes related to KGG in GT1-7 cells. In addition, 50 µM Cl3BPA significantly upregulated the phosphorylation of extracellular regulated protein kinases 1/2 (Erk1/2), the protein levels of GPER1 and the expression of the gper1 as well as the most target genes associated with mitogen-activated protein kinase (MAPK)/Erk1/2 pathways. Specific signal inhibitor experiments found that Cl3BPA activated KGG signals by activating the GPER1-mediated MAPK/Erk1/2 signaling pathway at the mRNA level. A docking test further confirmed the interactions between Cl3BPA and GPER1. The findings suggest that Cl3BPA might induce precocious puberty by increasing GnRH secretion together with KGG signaling upregulation, which is driven by GPER1-mediated signaling pathway. By comparison, ClxBPAs with fewer chlorine atoms had more obvious effects on the expression of proteins and partial genes related to KGG signals in GT1-7 cells.
Assuntos
Kisspeptinas , Maturidade Sexual , Kisspeptinas/genética , Kisspeptinas/metabolismo , Kisspeptinas/farmacologia , Linhagem Celular , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Transdução de SinaisRESUMO
The present study was conducted to elucidate (1) the influence of kisspeptin (KP) on the in vitro development of preantral follicles (PFs) and (2) evolution of KP receptor gene (KISS1R) expression during ovarian follicular development in sheep. Kisspeptin was supplemented (0-100 µg/ml) in the culture medium of PFs for 6 days. The cumulus-oocyte complexes (COCs) from cultured PFs were subsequently matured to metaphase II (MII) for an additional 24 h. The proportions of PFs exhibiting growth, antrum formation, average increase in diameter, and maturation of oocytes to MII stage were the indicators of follicular development in vitro. The expression of the kisspeptin receptor gene at each development stages of in vivo developed (preantral, early antral, antral, large antral and COCs from Graafian follicles) and in vitro cultured PFs supplemented with KP was assessed using a real-time polymerase chain reaction. The best development in all the parameters under study was elicited with 10 µg/ml of KP. Supplementation of KP (10 µg/ml) in a medium containing other growth factors (insulin-like growth factor-I) and hormones (growth hormone, thyroxine, follicle-stimulating hormone) resulted in better PF development. The KISS1R gene was expressed in follicular cells and oocytes at all the development stages of both in vivo developed and in vitro cultured follicles. Higher KISS1R gene expression was supported by culture medium containing KP along with other hormones and growth factors. Accordingly, it is suggested that one of the mechanisms through which KP and other growth factors and hormones influence the ovarian follicular development in mammals is through the upregulation of expression of the KP receptor gene.
Assuntos
Kisspeptinas , Oócitos , Feminino , Animais , Ovinos , Kisspeptinas/genética , Kisspeptinas/farmacologia , Receptores de Kisspeptina-1/genética , Oócitos/fisiologia , Folículo Ovariano , Hormônio Foliculoestimulante/farmacologia , MamíferosRESUMO
At this time, with advances in medical science, many cancers and chronic diseases are treatable, but one of their side effects is infertility. Some women also want to delay pregnancy for personal reasons. There has been some evidence that kisspeptin activates broad signals by binding to its receptor, suggesting that the role of kisspeptin in direct control of ovarian function includes follicle growth and steroid production. In this study, the effect of kisspeptin on improving the quality and results for human ovarian follicles was investigated. A section of ovary was removed laparoscopically from women between 20 and 35 years of age (n = 12). Pieces were divided randomly into two groups, control and treatment (with 1 µM kisspeptin). Real-time PCR was performed for GDF9, BMP15 and mTOR gene expression assessments. Western blotting was carried out to measure AKT and FOXO3a protein expression. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey's test; means were considered significantly different at a P-value < 0.05. During treatment with the kisspeptin group, maturity genes are expressed. Therefore, kisspeptin is an effective substance to improve the quality of the human ovarian medium as it increases the maturity of follicles.
Assuntos
Kisspeptinas , Ovário , Gravidez , Humanos , Feminino , Kisspeptinas/genética , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Folículo Ovariano/fisiologiaRESUMO
In Heteropneustes fossilis, kisspeptins (Kiss) and nonapeptides (NPs; vasotocin, Vt; isotocin, Itb; Val8-isotocin, Ita) stimulate the hypothalamus-pituitary-gonadal (HPG) axis, and estrogen feedback modulates the expression of these systems. In this study, functional interactions among these regulatory systems were demonstrated in the brain and ovary at the mRNA expression level. Human KISS1 (hKISS1) and H. fossilis Kiss2 (HfKiss2) produced biphasic effects on brain and ovarian vt, itb and ita expression at 24 h post injection: low and median doses produced inhibition, no change or mild stimulation, and the highest dose consistently stimulated the mRNA levels. The Kiss peptides produced an upregulation of NP mRNA expression at 24 h incubation of brain and ovarian slices by increasing the concentration of hKISS1 and HfKiss2. The kiss peptides stimulated brain cyp19a1b and ovary cyp19a1a expression, both in vivo and in vitro. Peptide234, a Kiss1 receptor antagonist, inhibited basal mRNA expression of the NPs, cyp19a1b and cyp19a1a, which was prevented by the Kiss peptides, both in vivo and in vitro. In all the experiments, HfKiss2 was more effective than hKISS1 in modulating mRNA expression. The results suggest that the NP and E2 systems are functional targets of Kiss peptides and interact with each other.
Assuntos
Peixes-Gato , Ovário , Feminino , Humanos , Animais , Ovário/metabolismo , Kisspeptinas/genética , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Peixes-Gato/metabolismo , Aromatase/genética , Aromatase/metabolismo , Encéfalo/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Kisspeptin (Kp-10) is a neuropeptide that binds to GPR54 receptors, exerting several functions mainly in the nervous and reproductive systems of the body. However, its effects and mechanisms of action on the skeletal system remain poorly understood. This study evaluated the effects of different concentrations of Kp-10 on in vitro osteogenic differentiation of multipotent mesenchymal stromal cells (MSCs) extracted from the bone marrow (BM) of adult Wistar rats. Two-month-old female rats were euthanized to extract BM from long bones to obtain MSCs. Four experimental groups were established in vitro: a control and Kp-10 at concentrations of 0.01, 0.05 and, 0.1 µg/mL. After induction of osteogenic differentiation, cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl tetrazolium bromide (MTT) assay, alkaline phosphatase activity, collagen synthesis, percentage of area covered by MSCs/field and mineralized nodules/field, and immunocytochemistry of the GPR54 receptor tests. Furthermore, evaluation of gene transcripts for type I collagen, Runx-2, Bmp-2, bone sialoprotein, osteocalcin and osteopontin was performed using real-time RT-qPCR. It was observed that MSCs expressed GPR54 receptor to which Kp-10 binds during osteogenic differentiation, promoting a negative effect on osteogenic differentiation. This effect was observed at all the Kp-10 concentrations in a concentration-dependent manner, characterized by a decrease in the activity of alkaline phosphatase, collagen synthesis, mineralized nodules, and decreased expression of gene transcripts for type I collagen, osteocalcin, osteopontin, and Runx-2. Thus, Kp-10 inhibits in vitro osteogenic differentiation of MSCs extracted from the BM of adult Wistar rats.
Assuntos
Kisspeptinas , Células-Tronco Mesenquimais , Osteogênese , Animais , Feminino , Ratos , Fosfatase Alcalina/metabolismo , Medula Óssea/metabolismo , Células da Medula Óssea/metabolismo , Diferenciação Celular , Células Cultivadas , Colágeno Tipo I/metabolismo , Kisspeptinas/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Osteocalcina/genética , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Osteopontina/metabolismo , Osteopontina/farmacologia , Ratos WistarRESUMO
We evaluated whether the administration of kisspeptin-10 (Kp10) is capable of restoring gonadal function in hypothyroid male rats. Hypothyroidism was induced with 6-propyl-2-thiouracil (PTU) for three months. In the last month, half of the hypothyroid animals were treated with Kp10. Hypothyroidism reduced testicular and sex gland mass, decreased the proliferation of the seminiferous epithelium, and compromised sperm morphology, motility, and vigor. A decrease in plasma LH and testosterone levels and an increase in prolactin secretion were observed in the hypothyroid rats. Hypothyroidism reduced Kiss1 and Kiss1r protein and gene expression and Star and Cyp11a1 mRNA levels in the testis. Furthermore, it reduced Lhb, Prl, and Drd2 and increased Tshb and Gnrhr expression in the pituitary. In the hypothalamus, hypothyroidism increased Pdyn and Kiss1r while reducing Gnrh1. Kp10 treatment in hypothyroid rats restored testicular and seminal vesicle morphology, improved sperm morphology and motility, reversed high prolactin levels, and increased LH and testosterone levels. In addition, Kp10 increased testicular expression of Kiss1, Kiss1r, Fshr, and Nr5a1 and pituitary Kiss1 expression. Our findings describe the inhibitory effects of hypothyroidism on the male gonadal axis and sperm quality and demonstrate that Kp10 treatment reverses high prolactin levels and improves gonadal function and sperm quality in hypothyroid rats.
Assuntos
Hipotireoidismo , Kisspeptinas , Ratos , Animais , Masculino , Kisspeptinas/farmacologia , Kisspeptinas/metabolismo , Prolactina/metabolismo , Hormônio Luteinizante , Receptores de Kisspeptina-1/metabolismo , Sêmen/metabolismo , Hipotireoidismo/metabolismo , Testículo/metabolismo , TestosteronaRESUMO
Kisspeptin is characterized as a neuropeptide with a pivotal function in female and male infertility, and its antioxidant properties have been demonstrated. In this study, the effects of kisspeptin on the improvement of the vitrification and thawing results of human ovarian tissues were investigated. In this work, 12 ovaries from patients who underwent hysterectomy were collected laparoscopically, and then 32 samples from each of their tissues were taken. Haematoxylin and eosin (H&E) staining was performed to check the normality of the ovarian tissue and, subsequently, the samples were allocated randomly into four groups, including: (1) fresh (control), (2) vitrification, (3) vitrified + 1 µM kisspeptin, and (4) vitrified + 10 µM kisspeptin groups. After vitrification, thawing, and tissue culture processes, H&E staining for tissue quality assessment, terminal deoxynucleotidyl transferase dUTP nick end labelling assay for apoptosis evaluation, and malondialdehyde (MDA), superoxide dismutase (SOD), and ferric reducing ability of plasma tests for oxidative stress appraisal were carried out. Our histological results showed incoherency of ovarian tissue morphology in the vitrification group compared with other groups. Other findings implicated increased apoptosis rate and MDA concentration and reduced SOD activity and total antioxidant capacity (TAC) in the vitrification group compared with the control group (P < 0.05). Moreover, decreased apoptosis rate and MDA concentration, and increased TAC and SOD function were observed in the vitrification with kisspeptin groups (1 µM and 10 µM) compared with the vitrified group (P < 0.05). Our reports express that kisspeptin is an effective agent to overcome the negative effects of vitrification by regulating reactive oxygen species-related apoptotic processes.