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1.
SAR QSAR Environ Res ; 34(9): 689-708, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37675795

RESUMO

In the current study, we used molecular screening and simulation approaches to target I7L protease from monkeypox virus (mpox) from the Traditional Chinese Medicines (TCM) database. Using molecular screening, only four hits TCM27763, TCM33057, TCM34450 and TCM31564 demonstrated better pharmacological potential than TTP6171 (control). Binding of these molecules targeted Trp168, Asn171, Arg196, Cys237, Ser240, Trp242, Glu325, Ser326, and Cys328 residues and may affect the function of I7L protease in in vitro assay. Moreover, molecular simulation revealed stable dynamics, tighter structural packing and less flexible behaviour for all the complexes. We further reported that the average hydrogen bonds in TCM27763, TCM33057, TCM34450 and TCM31564I7L complexes remained higher than the control drug. Finally, the BF energy results revealed -62.60 ± 0.65 for the controlI7L complex, for the TCM27763I7L complex -71.92 ± 0.70 kcal/mol, for the TCM33057I7L complex the BF energy was -70.94 ± 0.70 kcal/mol, for the TCM34450I7L the BF energy was -69.94 ± 0.85 kcal/mol while for the TCM31564I7L complex the BF energy was calculated to be -69.16 ± 0.80 kcal/mol. Although, we used stateoftheart computational methods, these are theoretical insights that need further experimental validation.


Assuntos
Medicina Tradicional Chinesa , Monkeypox virus , Simulação de Dinâmica Molecular , Peptídeo Hidrolases , Relação Quantitativa Estrutura-Atividade , Simulação de Acoplamento Molecular
2.
Acta Endocrinol (Buchar) ; 15(3): 283-288, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32010344

RESUMO

CONTEXT: Kisspeptin role in metabolism has been implicated recently. However, the nature of the signals that may connect body fat/muscle tissues with the central nervous system governing energy homeostasis remains to be elucidated. OBJECTIVE: The present study was designed to investigate the effects of peripheral kisspeptin-10 administration on irisin release in human males. SUBJECTS AND METHODS: Kisspeptin-10 was administered to normal weight (n=8) and obese (n=8) men. Sequential blood sampling was performed for 30 minutes pre and 210 minutes post kisspeptin injection at 30 minutes interval. ELISA kit was used to detect plasma irisin levels. RESULTS: There is a significant (P<0.0001) effect of Kisspeptin-10 administration on irisin release in both normal weight and obese participants. Mean irisin levels (96.24 ± 1.351 ng/mL) at 210 minutes were significantly (P<0.0001) enhanced as compared to pre-kisspeptin (59.18 ± 4.815 ng/mL) in normal weight subjects. In obese subjects mean irisin levels (75.76 ± 4.06 ng/mL) were significantly (P<0.0001) elevated at 180 minutes post-kisspeptin when compared with pre-kisspeptin irisin levels (41.28 ± 2.89 ng/mL). CONCLUSION: Our findings suggest that kisspeptin may have a novel therapeutic potential to induce irisin release in humans which may have anti-obesity effects.

3.
Cell Mol Biol (Noisy-le-grand) ; 63(8): 84-92, 2017 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-28886319

RESUMO

Time-lapse imaging technique has provided embryologists with a unique chance of studying the embryo morphokineticsto select the most viable embryos for implantation in the field of IVF (In vitro fertilization).The conventional method of morphological evaluations has proved that maternal age affects the human embryo quality. This retrospective study carried out at Islamabad Clinic Serving Infertile Couples, Islamabad, Pakistan mainly focuses on the effect of female age on human embryo morphokinetics. A total number of 200 patients undergoing ICSI treatment cycles at the clinic were selected for the study and divided into five age groups (< 26, 26-30, 31-35, 36-40, and > 40 years). Embryo culture was done at 37°C, 6% CO2 and 5% oxygen for 5-6 days. Ten time-points were selected for kinetic analysis. The number of retrieved, matured, fertilized and cleaved oocytes showed highly significant difference (P≤ 0.0001) when compared among different age groups. There was no significant difference in average morphokinetic time-points among young versus old women.Whereas timely cleaved embryos showed significant difference in tPNa i.e. time for pronuclear appearance (P≤ 0.001), t4 and t5 i.e. time for 4 and 5-cell cleavage (P≤ 0.05)among different age groups. The clinical pregnancy rates showed a decline with increasing age. These results indicate the effect of female age on time-lapse embryo morphokinetic parameters. In future the addition of time-lapse analysis in routine IVF can help to improve the success rate by selecting the most viable embryos for uterine transfer.


Assuntos
Técnicas de Cultura Embrionária/métodos , Implantação do Embrião/fisiologia , Desenvolvimento Embrionário/fisiologia , Fertilização in vitro/métodos , Imagem com Lapso de Tempo/instrumentação , Adulto , Fatores Etários , Blastocisto/citologia , Blastocisto/fisiologia , Transferência Embrionária , Feminino , Humanos , Cinética , Masculino , Oócitos/citologia , Oócitos/fisiologia , Paquistão , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Espermatozoides/citologia , Espermatozoides/fisiologia
4.
J Headache Pain ; 18(1): 28, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28229320

RESUMO

BACKGROUND: The large geographical gaps in our knowledge of the prevalence and burden of headache disorders include almost all of Eastern Mediterranean Region (EMR). We report a nationwide population-based study in Pakistan, an EMR country with the sixth largest population in the world, conducted as a project within the Global Campaign against Headache. METHODS: We surveyed six locations from the four provinces of Pakistan: Punjab, Sindh, Khyber Pakhtunkhwa and Baluchistan. We randomly selected and visited rural and urban households in each. One adult member (18-65 years) of each household, also randomly selected, was interviewed by a trained non-medical interviewer from the same location using a previously-validated structured questionnaire translated into Urdu, the national language. We estimated 1-year prevalences of the headache disorders of public-health importance and examined their associations with demographic variables using multivariate analysis. RESULTS: There were 4223 participants (mean age 34.4 ± 11.0 years; male 1957 [46.3%], female 2266 [53.7%]; urban 1443 [34.2%], rural 2780 [65.8%]). Participation proportion was 89.5%. Headache in the previous year was reported by 3233 (76.6% [95% CI: 75.3-77.8%]). The age- and gender-adjusted 1-year prevalence of migraine was 22.5% [21.2-23.8%] (male 18.0% [16.8-19.2%], female 26.9% [25.6-28.2%]), of tension-type headache (TTH) 44.6% [43.1-46.1%] (male 51.2% [49.7-52.7%], female 37.9% [36.4-39.4%]), of probable medication-overuse headache 0.7% [0.5-1.0%] (male 0.7% [0.5-1.0%], female 0.8% [0.5-1.1%]) and of other headache on ≥15 days/month 7.4% [6.6-8.2%] (male 4.4% [3.8-5.0%], female 10.4% [9.5-11.3%]). Migraine was more prevalent in females by a factor of 3:2 although this association barely survived (P = 0.039) after correcting for other factors. TTH was more prevalent in males by about 4:3 (P = 0.026). All headache and migraine were age-related, peaking in the age group 40-49 years; TTH peaked a decade earlier. Higher education (P = 0.004) and income (P = 0.001) were negatively associated with prevalence of migraine. CONCLUSION: With three quarters of its population affected, headache disorders must be on the public-health agenda of Pakistan. Worldwide, these disorders are the third leading cause of disability; information from specific enquiry into the burden attributable to headache disorders in this country is needed to inform health policy and priority-setting, and will be reported soon.


Assuntos
Transtornos da Cefaleia Primários/epidemiologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Transtornos da Cefaleia Secundários/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos de Enxaqueca/epidemiologia , Paquistão/epidemiologia , Prevalência , Cefaleia do Tipo Tensional/epidemiologia , Adulto Jovem
5.
Andrologia ; 48(10): 1166-1174, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26892806

RESUMO

This study was designed to investigate the occurrence of bacterial species in water buffalo semen at the time of collection/processing and to assess the efficacy of some selected antibiotics (GTLS; gentamycin, tylosin and linco-spectin or SP; streptomycin and penicillin) in cryodiluent on bacterial control and quality including in vivo fertility of buffalo spermatozoa. For this purpose, four experiments were conducted. In experiment 1, a total of 11 bacterial species were isolated from buffalo ejaculates. In experiment 2, total aerobic bacterial counts at post dilution and thawing were lower (P < 0.05) in GTLS than in SP or control. The majority of the bacterial isolates from ejaculates were more susceptible to GTLS than SP. In experiment 3, sperm acrosome integrity was higher (P < 0.05) in GTLS and SP compared to control. In experiment 4, the in vivo fertility results for GTLS were higher (P < 0.05) than that for SP. In conclusion, a number of bacterial species were isolated from the bubaline semen, which requires an efficient control before its use in artificial insemination program. The GTLS combination of antibiotics may be incorporated into a freezing extender/protocol without compromising the post-thaw quality and in vivo fertility of buffalo bull spermatozoa.


Assuntos
Bactérias/isolamento & purificação , Criopreservação/métodos , Preservação do Sêmen/métodos , Sêmen/microbiologia , Animais , Antibacterianos/farmacologia , Búfalos , Crioprotetores/farmacologia , Masculino , Análise do Sêmen , Espermatozoides/microbiologia
6.
Endocrinology ; 156(10): 3717-24, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26181107

RESUMO

A somatic signal has been posited to trigger the pubertal resurgence in pulsatile GnRH secretion that initiates puberty in highly evolved primates. That GH might provide such a signal emerged in 2000 as a result of a study reporting that circulating nocturnal GH concentrations in castrated juvenile male monkeys increased in a 3-week period immediately preceding the pubertal resurgence of LH secretion. The present study was conducted to reexamine this intriguing relationship, again in an agonadal model. Four castrated juvenile male monkeys were implanted with indwelling jugular catheters, housed in remote sampling cages, and subjected to 24 hours of sequential blood sampling (every 30 min) every 2 weeks from 19.5 to 22 months of age. Twenty-four-hour profiles of circulating GH concentrations were analyzed using the pulse detection algorithm, PULSAR, and developmental changes in pulsatile GH release with respect to the initiation of the pubertal rise of LH secretion (week 0; observed between 22.5 and 32 mo of age) were examined for significance by a repeated-measures ANOVA. Changes in the parameters of pulsatile GH secretion, including mean 24-hour GH concentration and GH pulse frequency and pulse amplitude for 3 (n = 4) and 6 (n = 3) months before week 0 were unremarkable and nonsignificant. These findings fail to confirm those of the earlier study and lead us to conclude that the timing of the pubertal resurgence of GnRH release in the male monkey is not dictated by GH. Reasons for the discrepancy between the two studies are unclear.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Gônadas/fisiologia , Hormônio do Crescimento/metabolismo , Maturidade Sexual/fisiologia , Algoritmos , Análise de Variância , Animais , Humanos , Hormônio Luteinizante/metabolismo , Macaca mulatta , Masculino , Orquiectomia , Fluxo Pulsátil , Radioimunoensaio , Taxa Secretória , Fatores de Tempo
7.
J Endocrinol ; 225(2): R49-66, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25957191

RESUMO

Recently, kisspeptin (KP) and gonadotropin inhibitory hormone (GnIH), two counteracting neuropeptides, have been acknowledged as significant regulators of reproductive function. KP stimulates reproduction while GnIH inhibits it. These two neuropeptides seem to be pivotal for the modulation of reproductive activity in response to internal and external cues. It is well-documented that the current metabolic status of the body is closely linked to its reproductive output. However, how reproductive function is regulated by the body's energy status is less clear. Recent studies have suggested an active participation of hypothalamic KP and GnIH in the modulation of reproductive function according to available metabolic cues. Expression of KISS1, the KP encoding gene, is decreased while expression of RFRP (NPVF), the gene encoding GnIH, is increased in metabolic deficiency conditions. The lower levels of KP, as suggested by a decrease in KISS1 gene mRNA expression, during metabolic deficiency can be corrected by administration of exogenous KP, which leads to an increase in reproductive hormone levels. Likewise, administration of RF9, a GnIH receptor antagonist, can reverse the inhibitory effect of fasting on testosterone in monkeys. Together, it is likely that the integrated function of both these hypothalamic neuropeptides works as a reproductive output regulator in response to a change in metabolic status. In this review, we have summarized literature from nonprimate and primate studies that demonstrate the involvement of KP and GnIH in the metabolic regulation of reproduction.


Assuntos
Hormônios Hipotalâmicos/metabolismo , Kisspeptinas/metabolismo , Reprodução , Animais , Humanos , Hormônios Hipotalâmicos/genética , Hipotálamo/metabolismo , Kisspeptinas/genética
8.
Horm Metab Res ; 46(13): 927-832, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25181419

RESUMO

Recently, hypothalamic RFRP-3 (a mammalian ortholog of avian GnIH) signaling has been proposed as an important negative modulator of the reproductive axis. The current study examined whether repression of reproductive hormonal expression during short-term fasting conditions in higher-order primate is influenced by altered RFRP-3 signaling. Eight intact postpubertal male macaques (Macaca mulatta) were administered a single intravenous bolus of RF-9 (n = 4), a potent and putative RFRP-3 receptor antagonist, or vehicle (n = 4) following a 48-h fasting condition. Intermittent blood samples were collected every 30 min during the 4-h post-bolus period, and blood glucose, plasma cortisol, and testosterone concentrations were measured. Relative to fed conditions, fasting reduced glucose and testosterone levels (p < 0.005) and increased cortisol levels (p < 0.05). Relative to baseline, mean testosterone levels were elevated 150 min after RF-9 (p < 0.05) but not vehicle administration. In addition, elevated mean plasma testosterone levels following RF-9 administration were equivalent to levels observed in normal fed monkeys. These results suggest an important role for RFRP-3 signaling in conveying metabolic state information to the reproductive axis in higher primates.


Assuntos
Adamantano/análogos & derivados , Dipeptídeos/administração & dosagem , Dipeptídeos/farmacologia , Jejum/fisiologia , Gônadas/fisiologia , Sistema Hipotálamo-Hipofisário/metabolismo , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Adamantano/administração & dosagem , Adamantano/farmacologia , Administração Intravenosa , Animais , Glicemia/metabolismo , Jejum/sangue , Comportamento Alimentar , Gônadas/efeitos dos fármacos , Hidrocortisona/sangue , Macaca , Masculino , Testosterona/sangue
9.
Horm Metab Res ; 46(3): 187-92, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24500987

RESUMO

Metabolism and reproduction are closely linked. Both long- and short-term fasting-induced metabolic deficiency suppresses reproductive function in mammals. Recently, we have shown that 48-h fasting-induced metabolic deficiency attenuates the reproductive axis responsiveness to peripheral kisspeptin injection in the sexually mature monkeys. But currently there is no data to show whether shorter time periods of fasting also alter the reproductive axis responsiveness to kisspeptin. Therefore, this study was aimed to examine the reproductive axis responsiveness to kisspeptin administration in the adult male rhesus monkey fasted for 12-, 18-, and 24h. Intravenous boli of vehicle (1 ml) and human kisspeptin-10 (KP10; 50 µg) were given to 5 intact sexually mature male rhesus monkeys in both fasting (12-, 18-, 24-h) and ad libitum feeding conditions. Specific immunoassays were used to determine plasma hormones concentrations. KP10 injection highly stimulated testosterone secretion in all conditions. However, mean testosterone concentrations in 3-h post-KP10 injection period were significantly (p<0.01) decreased in 18- and 24-h fasted monkeys when compared to 12-h fasted and fed monkeys. Moreover, 18- and 24-h fasting conditions also significantly (p<0.05) delayed the duration to the first significant increase in T levels after KP10 injection. Vehicle injection did not alter these parameters in any conditions. Present results indicate that 18- and 24-h fasting conditions suppressed the testosterone response to KP10 administration both in initiation and quantity. These results suggest that 18- and 24-h fasting-induced inhibition of the reproductive functions in the mature male macaque may partly involve attenuation in the reproductive axis responsiveness to endogenous kisspeptin stimulation.


Assuntos
Privação de Alimentos , Sistema Hipotálamo-Hipofisário/metabolismo , Kisspeptinas/farmacologia , Macaca mulatta/metabolismo , Testículo/metabolismo , Adiponectina/sangue , Animais , Glicemia/metabolismo , Jejum/sangue , Comportamento Alimentar/efeitos dos fármacos , Humanos , Hidrocortisona/sangue , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Injeções , Kisspeptinas/administração & dosagem , Leptina/sangue , Masculino , Testículo/efeitos dos fármacos , Testosterona/sangue , Fatores de Tempo
10.
Andrologia ; 46(6): 610-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23758287

RESUMO

Kisspeptin-Kiss1R signalling in mammals has been implicated as an integral part of the reproductive cascade. Kisspeptinergic neurons upstream of GnRH neurons are involved in the activation of the hypothalamic GnRH pulse generator during pubertal onset. Thus, the major research focus has been on the central effects of kisspeptin. The demonstration of the presence of KissR expression in human testes suggests additional unknown actions of kisspeptin-KISS1R signalling at the distal component of the male reproductive axis. Here we explored the impact of kisspeptin at the testis in the adult male rhesus monkey. We employed the clamped monkey model to assess the intratesticular actions of kisspeptin. Plasma testosterone and LH levels were monitored in four adult male monkeys. The peripheral administration of human kisspeptin-10 (50 µg, iv bolus) caused a single LH pulse, which was followed by a robust increase in plasma testosterone levels sustained for at least 180 min. This response was abolished when kisspeptin was administered to GnRH receptor antagonist (acyline) pre-treated animals. However, kisspeptin administration significantly (P < 0.005) elevated hCG-stimulated testosterone levels in acyline pre-treated monkeys when compared with saline+ hCG treatment. These results revealed a novel peripheral facet of kisspeptin signalling.


Assuntos
Kisspeptinas/fisiologia , Macaca mulatta/fisiologia , Testículo/fisiologia , Animais , Gonadotropina Coriônica/administração & dosagem , Humanos , Kisspeptinas/administração & dosagem , Hormônio Luteinizante/sangue , Macaca mulatta/sangue , Masculino , Oligopeptídeos/administração & dosagem , Receptores Acoplados a Proteínas G/fisiologia , Receptores LHRH/antagonistas & inibidores , Transdução de Sinais , Testículo/efeitos dos fármacos , Testosterona/sangue
11.
Horm Metab Res ; 44(6): 451-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22473757

RESUMO

Hypoglycemia inhibits the hypothalamic-pituitary-gonadal (HPG) axis by still incompletely deciphered mechanisms. Many evidences suggest that the hypoglycemia-induced inhibition of the HPG axis involves alteration of the hypothalamic gonadotropin-releasing hormone (GnRH) release, but neuroendocrine factors responsible for this alteration are yet to be completely elucidated. The current study was carried out to ascertain whether insulin-induced hypoglycemic suppression of the HPG axis involves modulation of responsiveness of the GnRH neuron to kisspeptin and excitatory amino acids (EAA) drives. Five intact chair-restraint habituated adult male rhesus monkeys (Macaca mulatta) were given intravenous boli of GnRH, hCG, human kisspeptin-10 (KP10), NMDA (N-methyl-D, L-aspartate, an EAA analogue), and vehicle in both insulin (1 IU/kg)-induced hypoglycemic (IIH) and normal euglycemic conditions. Specific RIAs were used for measuring plasma cortisol and T concentrations. KP10 and NMDA administration stimulated significantly (p<0.005) T secretion in both euglycemic and hypoglycemic monkeys. Mean post-KP10 T concentrations and AUC were comparable between euglycemic and hypoglycemic monkeys. However, mean post-NMDA T levels and AUC in hypoglycemic animals were significantly lower (p<0.01-0.005) as compared to the corresponding values in euglycemic animals. T response to GnRH and hCG was similar between hypoglycemic and euglycemic monkeys. Vehicle did not affect plasma T concentrations in all conditions. Our results demonstrate that while the primate HPG axis response to kisspeptin stimulation remains intact that to EAA excitation is attenuated in hypoglycemic conditions, suggesting that hypogonadism in IIH is contributed, in part, by reduced sensitivity of the GnRH neurons to EAA signaling in the primate hypothalamus.


Assuntos
Glicemia/metabolismo , Hipoglicemia/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Kisspeptinas/farmacologia , Macaca mulatta/metabolismo , N-Metilaspartato/farmacologia , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Animais , Área Sob a Curva , Glicemia/efeitos dos fármacos , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/farmacologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Hidrocortisona/sangue , Hipoglicemia/sangue , Sistema Hipotálamo-Hipofisário/metabolismo , Injeções Intravenosas , Kisspeptinas/administração & dosagem , Masculino , N-Metilaspartato/administração & dosagem , Sistema Hipófise-Suprarrenal/metabolismo , Testosterona/sangue , Testosterona/metabolismo , Fatores de Tempo
12.
J Dent (Tehran) ; 8(1): 12-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21998802

RESUMO

OBJECTIVE: Predoctoral dental implant education is included in dental school teaching curricula in most of the developed and some developing countries; however, it was not introduced into undergraduate curriculum of some countries and Iranian dental schools. Our purpose was to investigate the status of the predoctoral dental implant education of dental schools in the world. MATERIALS AND METHODS: One hundred-thirty five dental schools were randomly selected representing 62 countries divided into two regions. The first region included North America and Europe, and the second region comprised of Asia, South America and Africa. A questionnaire including onset year, lecture hours, lectures available on the internet, required textbooks, department jurisdictions, the year of dental school the course was offered, clinical and laboratory courses, implant systems used surgically and in restorative phase, and type of restorations treated by predoctoral students was mailed electronically to the predoctoral implant dentistry directors. RESULTS: Ninety-two (68%) schools responded; of which 79 (86%) incorporated implant dentistry in their predoctoral teaching curricula, 39 (49%) offered surgical and prosthodontics courses in which students mainly observe. Of these 39 dental schools, 28 (71%) and 11 (29%) dental schools are from the first and second region, respectively. CONCLUSION: A large percentage of responding schools included implant education in the predoctoral dental curriculum. Onset year of course, topics included in lecture series, lecture hours, faculty to student ratio and practical course vary among schools. Fifty percent of responding dental schools including Iranian dental schools do not have curriculum guidelines for predoctoral implant dentistry.

13.
J Biol Chem ; 286(36): 31064-71, 2011 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-21757754

RESUMO

Estrogen receptor α (ERα) regulates gene transcription via "genomic" (binding directly or indirectly, typically via Sp1 or AP-1 sites, to target genes) and/or "nongenomic" (signaling) mechanisms. ERα activation by estrogen up-regulates the murine Ca(2+)-activated K(+) channel α subunit gene (mSlo1) via genomic mechanisms. Here, we investigated whether ERα also drives transcription of the human (hSlo1) gene. Consistent with this view, estrogen increased hSlo1 transcript levels in primary human smooth muscle cells. Promoter studies revealed that estrogen/hERα-mediated hSlo1 transcription was nearly 6-fold more efficient than for mSlo1 (EC(50), 0.07 versus 0.4 nM). Unlike the genomic transcriptional mechanism employed by mSlo1, hSlo1 exhibits a nongenomic hERα-mediated regulatory mechanism. This is supported by the following: 1) efficient hSlo1 transcription after disruption of the DNA-binding domain of hERα or knockdown of Sp1, and 2) lack of AP-1 sites in the hSlo1 promoter. Three nongenomic signaling pathways were explored: Src, Rho, and PI3K. Inhibition of Src with 10 µM PP2, and reported downstream ERK with 25 µM PD98059 did not prevent estrogen action but caused an increase in hSlo1 basal transcription; conversely, constitutively active c-Src (Y527F) decreased hSlo1 basal transcription even preventing its estrogen/hERα-mediated transcriptional activation. Rho inhibition by coexpressed Clostridium botulinum C3 transferase did not alter estrogen action. In contrast, inhibition of PI3K activity with 10 µM LY294002 decreased estrogen-stimulated hSlo1 transcription by ∼40%. These results indicate that the nongenomic PI3K signaling pathway plays a role in estrogen/hERα-stimulated hSlo1 gene expression; whereas c-Src activity leads to hSlo1 gene tonic repression independently of estrogen, likely through ERK activation.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Regulação da Expressão Gênica/fisiologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Proteínas Tirosina Quinases/metabolismo , Transcrição Gênica , Adolescente , Proteína Tirosina Quinase CSK , Células Cultivadas , Criança , MAP Quinases Reguladas por Sinal Extracelular , Feminino , Humanos , Masculino , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/fisiologia , Fosfatidilinositol 3-Quinases , Quinases da Família src
14.
Horm Metab Res ; 43(2): 81-5, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21154197

RESUMO

Fasting suppresses functioning of the hypothalamic-pituitary-gonadal (HPG) axis by mechanisms that are incompletely understood. In 2003, hypothalamic kisspeptin-Kiss1r signaling was discovered to play a significant role in regulating the HPG axis. We have recently shown that in adult male macaques, short-term fasting attenuates the response of the HPG axis to an exogenous kisspeptin challenge. In the present study, we explored the mechanism underlying this attenuated response by examining the modulation of the hypothalamic expression of KISS1 and KISS1R under short-term fasting and normal feeding conditions in the adult male macaques. Hypothalamic mRNA was extracted from normal fed (n=3) and 48-h fasted (n=3) monkeys. KISS1, KISS1R, and GNRH1 mRNA were quantified by reverse transcription followed by real-time polymerase chain reaction. In addition, blood samples were collected for measurement of plasma concentrations of glucose, cortisol, leptin, and testosterone. In contrast to fed animals, plasma glucose, leptin, and testosterone levels decreased and cortisol levels increased in fasted animals. The hypothalamic expression of KISS1 and KISS1R mRNA was significantly lower (p<0.05) in fasted monkeys compared to fed monkeys while hypothalamic GNRH1 mRNA expression was comparable between the 2 groups. Thus, our results demonstrate that expression of hypothalamic KISS1 and KISS1R decrease after a short-term fasting in monkeys. This decrease may contribute to the suppression of the HPG axis during fasting conditions in primates. In addition, our finding of lower expression of KISS1R in fasted monkeys provides an explanation for the attenuation in the HPG axis response to peripheral kisspeptin challenge during short-term fasting.


Assuntos
Regulação para Baixo , Gônadas/metabolismo , Hipotálamo/metabolismo , Macaca mulatta/genética , Hipófise/metabolismo , Receptores de Neuropeptídeos/genética , Proteínas Supressoras de Tumor/genética , Animais , Glicemia , Jejum/metabolismo , Macaca mulatta/metabolismo , Masculino , Receptores de Neuropeptídeos/metabolismo , Proteínas Supressoras de Tumor/metabolismo
15.
Horm Metab Res ; 43(1): 37-42, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21136344

RESUMO

Kisspeptin (KP)-Kiss1r, a ligand-receptor pair, has recently been implicated as a pivotal regulator of the neuroendocrine reproductive axis. KISS1 (encoding KP) as well as KISS1R (encoding receptor for KP) are expressed in several peripheral tissues including the pancreas. But the specific role of KP in the physiology of pancreas is still incompletely deciphered. This study was designed to examine the effect of peripheral KP administration on basal and glucose-induced plasma insulin (an important pancreatic hormone) secretion under fed and fasting conditions in the adult male rhesus monkey. A set of 4 chair-restraint habituated intact adult male rhesus monkeys were assigned to receive intravenous bolus administration of human kisspeptin-10 (KP10, 50 µg), and vehicle (1 ml) in normal fed and fasting conditions without or with glucose infusions. Plasma concentrations of insulin were measured by using a specific IRMA. Glucose infusion significantly stimulated plasma insulin levels (p<0.005). Vehicle administration did not affect both basal and glucose stimulated insulin in fed as well as in fasting condition. KP10 administration had no effect on the basal insulin levels in both fed and fasting as compared to pretreatment or vehicle treatment levels, while it significantly heightened glucose stimulated insulin levels (p<0.05) in both fed and fasted monkeys. The present results show that KP administration does not affect the basal secretion of insulin under both fed and fasting condition while potentiated the glucose-induced insulin levels in the adult male rhesus monkey. Therefore, these findings suggest a potential role of KP in the physiology of pancreas.


Assuntos
Jejum/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Proteínas Supressoras de Tumor/administração & dosagem , Animais , Humanos , Insulina/sangue , Secreção de Insulina , Kisspeptinas , Macaca mulatta , Masculino , Modelos Animais , Proteínas Supressoras de Tumor/metabolismo
16.
Horm Metab Res ; 42(8): 570-4, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20446240

RESUMO

In the last few years, kisspeptin-KISS1R signaling has appeared as a major regulator of the reproductive function in several vertebrate species. However, KISS1(encoding kisspeptin) and its putative receptor, KISS1R, are expressed in several other tissues. Adipose tissue, which secretes many peptides with diverse functions in normal physiology, expresses KISS1, which is modulated by gonadal steroids as well as by body nutritional status. Similarly, KISS1Rexpression is also found in adipose tissue, but the local role of kisspeptin in adipocyte function is currently unknown. Therefore, in the present study the effects of exogenous human kisspeptin-10 (KP10) were studied on three important adipokines, namely, adiponectin, leptin, and resistin in a set of four chair-restraint habituated intact adult male rhesus monkeys under; 1) normal fed conditions, 2) 24-h fasting conditions, and 3) 48-h fasting conditions. Plasma resistin and leptin levels decreased (p<0.01), whereas adiponectin levels increased (p<0.05) in fasted monkeys. Kisspeptin administration significantly increased (p<0.05) mean plasma adiponectin levels under fed and 24-h fasting conditions as compared to pretreatment or vehicle-treatment levels. A stimulatory effect was also observed on the 48-h fasting stimulated plasma adiponectin levels, but it lacked statistical significance. In contrast, no effect of kisspeptin was observed on mean plasma leptin and resistin levels. Thus, the present study demonstrated a stimulatory effect of peripheral kisspeptin administration on the plasma adiponectin levels under fed and 24-h fasting conditions in the adult male rhesus monkey. These findings, therefore, assign a novel role to kisspeptin, a regulator of adipocyte function in higher primate.


Assuntos
Adiponectina/metabolismo , Jejum/fisiologia , Comportamento Alimentar/efeitos dos fármacos , Leptina/metabolismo , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacologia , Resistina/metabolismo , Adiponectina/sangue , Envelhecimento/fisiologia , Animais , Jejum/sangue , Humanos , Injeções Intravenosas , Kisspeptinas , Leptina/sangue , Macaca mulatta/sangue , Masculino , Resistina/sangue , Fatores de Tempo
17.
Theriogenology ; 73(1): 20-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19815266

RESUMO

Fifteen longitudinally reared Nili-Ravi buffalo bulls (Bubalus bubalis) were slaughtered at 1, 6, 12, 18, and 24 mo of age (n=3 per group) to observe testicular development and to examine qualitatively the establishment of spermatogenesis. With the age held constant, scrotal circumference and testes weight were correlated (0.95; P<0.05). Testes weight increased from 3.5+/-0.7 at 1 mo of age to 185+/-30g at 24 mo of age. Seminiferous tubules diameter developed in a linear fashion (57microm at 1 mo and 178microm at 24 mo), and the lumen formed at 12 mo of age. Differentiation of basal indifferent supporting cells to Sertoli cells started at 6 mo, and formation of Sertoli cells completed near 12 mo of age. Gonocytes predominated at 1 mo, but by 12 mo, most had been replaced by spermatogonia, thus rapid proliferation of tubular contents occurred at 12 mo (testes weight=75g). Spermatocytes were first observed at 12 mo, and their number increased through 18 and 24 mo. Establishment of spermatogenesis, as reflected by appearance of significant number of spermatids, occurred by 18 mo of age (testes weight 122g). Thus, the establishment of spermatogenesis was progressive from birth, and marked changes were observed during the last 6 mo.


Assuntos
Búfalos/crescimento & desenvolvimento , Espermatogênese/fisiologia , Testículo/crescimento & desenvolvimento , Fatores Etários , Animais , Búfalos/anatomia & histologia , Diferenciação Celular , Masculino , Túbulos Seminíferos/anatomia & histologia , Túbulos Seminíferos/citologia , Túbulos Seminíferos/crescimento & desenvolvimento , Células de Sertoli/citologia , Testículo/anatomia & histologia , Testículo/citologia
18.
Gene Expr Patterns ; 9(5): 255-65, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19393343

RESUMO

Cell-cell communication is critical for regulating embryonic organ growth and differentiation. The Bone Morphogenetic Protein (BMP) family of transforming growth factor beta (TGFbeta) molecules represents one class of such cell-cell signaling molecules that regulate the morphogenesis of several organs. Due to high redundancy between the myriad BMP ligands and receptors in certain tissues, it has been challenging to address the role of BMP signaling using targeting of single Bmp genes in mouse models. Here, we present a detailed study of the developmental expression profiles of three BMP ligands (Bmp2, Bmp4, Bmp7) and three BMP receptors (Bmpr1a, Bmpr1b, and BmprII), as well as their molecular antagonist (noggin), in the early embryo during the initial steps of murine organogenesis. In particular, we focus on the expression of Bmp family members in the first organs and tissues that take shape during embryogenesis, such as the heart, vascular system, lungs, liver, stomach, nervous system, somites and limbs. Using in situ hybridization, we identify domains where ligand(s) and receptor(s) are either singly or co-expressed in specific tissues. In addition, we identify a previously unnoticed asymmetric expression of Bmp4 in the gut mesogastrium, which initiates just prior to gut turning and the establishment of organ asymmetry in the gastrointestinal tract. Our studies will aid in the future design and/or interpretation of targeted deletion of individual Bmp or Bmpr genes, since this study identifies organs and tissues where redundant BMP signaling pathways are likely to occur.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/genética , Embrião de Mamíferos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Animais , Proteína Morfogenética Óssea 2/genética , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 7/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Proteínas de Transporte/genética , Embrião de Mamíferos/embriologia , Feminino , Perfilação da Expressão Gênica , Coração/embriologia , Hibridização In Situ , Fígado/embriologia , Pulmão/embriologia , Camundongos , Organogênese/genética , Gravidez , Fatores de Tempo
19.
Structure ; 16(10): 1532-43, 2008 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-18940608

RESUMO

G12 class heterotrimeric G proteins stimulate RhoA activation by RGS-RhoGEFs. However, p115RhoGEF is a GTPase Activating Protein (GAP) toward Galpha13, whereas PDZRhoGEF is not. We have characterized the interaction between the PDZRhoGEF rgRGS domain (PRG-rgRGS) and the alpha subunit of G13 and have determined crystal structures of their complexes in both the inactive state bound to GDP and the active states bound to GDP*AlF (transition state) and GTPgammaS (Michaelis complex). PRG-rgRGS interacts extensively with the helical domain and the effector-binding sites on Galpha13 through contacts that are largely conserved in all three nucleotide-bound states, although PRG-rgRGS has highest affinity to the Michaelis complex. An acidic motif in the N terminus of PRG-rgRGS occupies the GAP binding site of Galpha13 and is flexible in the GDP*AlF complex but well ordered in the GTPgammaS complex. Replacement of key residues in this motif with their counterparts in p115RhoGEF confers GAP activity.


Assuntos
Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/química , Subunidades alfa G12-G13 de Proteínas de Ligação ao GTP/metabolismo , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Sequência de Aminoácidos , Animais , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Guanosina 5'-O-(3-Tiotrifosfato)/metabolismo , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Proteínas RGS/química , Ratos , Homologia de Sequência de Aminoácidos , Especificidade por Substrato/genética
20.
Mol Cell Biochem ; 317(1-2): 51-9, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18560765

RESUMO

In vitro studies have shown unequivocally that bilirubin is an antioxidant. We hypothesized that bilirubin serves a physiological role of an antioxidant in vivo. To investigate the probable protective role of bilirubin in vivo, term babies with clinical jaundice were grouped into four categories-serum total bilirubin (STB) <160 mg/l, 160-200 mg/l, >200 mg/l, and kernicterus. Serum bilirubin, serum albumin, plasma glucose-6-phosphate dehydrogenase (G6PD), lipid peroxidation in blood cells, and reduced glutathione (GSH) content in whole blood were investigated. We also measured superoxide dismutase (SOD) and catalase in hemolysate and total plasma antioxidant capacity (TAC). Lipid peroxidation and antioxidant enzymes were significantly lower in babies with STB <200 mg/l compared to controls. TAC had a positive and MDA had a negative correlation with STB till 200 mg/l. However, TAC had a negative and MDA had a positive correlation with bilirubin >200 mg/l and in babies with bilirubin encephalopathy. Elevated levels of MDA, SOD, and catalase and significantly decreased levels of reduced glutathione and total antioxidant capacity were observed in STB >200 mg/l group. Antioxidant enzymes were also significantly inhibited in bilirubin encephalopathy babies. Post phototherapy, MDA production and antioxidant levels were significantly increased whilst total antioxidant capacity and reduced glutathione were significantly decreased compared to pre-phototherapy values. Exchange transfusion resulted in reduced oxidative stress in subjects with encephalopathy, whereas no significant difference was observed in other babies with STB >200 mg/l. Taken together, the present study propounds that bilirubin acts as a physiological antioxidant till 200 mg/l concentration in full-term normal neonates. It is conjectured that beyond 200 mg/l, it can no longer be considered physiologic. However, the cause of pathological jaundice needs to be identified and treated. The present data documents that phototherapy also induces oxidative stress.


Assuntos
Antioxidantes/metabolismo , Bilirrubina/sangue , Citoproteção , Idade Gestacional , Recém-Nascido/sangue , Oxidantes/sangue , Demografia , Transfusão Total , Humanos , Estresse Oxidativo , Fototerapia
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