Displaying publications 21 - 40 of 46 in total

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  1. Parhar IS, Ogawa S, Ubuka T
    PMID: 27065948 DOI: 10.3389/fendo.2016.00028
    Social behaviors are key components of reproduction, because they are essential for successful fertilization. Social behaviors, such as courtship, mating, and aggression, are strongly associated with sex steroids, such as testosterone, estradiol, and progesterone. Secretion of sex steroids from the gonads is regulated by the hypothalamus-pituitary-gonadal (HPG) axis in vertebrates. Gonadotropin-releasing hormone (GnRH) is a pivotal hypothalamic neuropeptide that stimulates gonadotropin release from the pituitary. In recent years, the role of neuropeptides containing the C-terminal Arg-Phe-NH2 (RFamide peptides) has been emphasized in vertebrate reproduction. In particular, two key RFamide peptides, kisspeptin and gonadotropin-inhibitory hormone (GnIH), emerged as critical accelerator and suppressor of gonadotropin secretion. Kisspeptin stimulates GnRH release by directly acting on GnRH neurons, whereas GnIH inhibits gonadotropin release by inhibiting kisspeptin, GnRH neurons, or pituitary gonadotropes. These neuropeptides can regulate social behavior by regulating the HPG axis. However, distribution of neuronal fibers of GnRH, kisspeptin, and GnIH neurons is not limited within the hypothalamus, and the existence of extrahypothalamic neuronal fibers suggests direct control of social behavior within the brain. It has traditionally been shown that central administration of GnRH can stimulate female sexual behavior in rats. Recently, it was shown that Kiss1, one of the paralogs of kisspeptin peptide family, regulates fear responses in zebrafish and GnIH inhibits sociosexual behavior in birds. Here, we highlight recent findings regarding the role of GnRH, kisspeptin, and GnIH in the regulation of social behaviors in fish, birds, and mammals and discuss their importance in future biological and biomedical research.
    Matched MeSH terms: Pituitary Gland
  2. Wong JSL, Nasruddin AB, Selveindran NM, Latif KA, Kassim F, Nair SB, et al.
    AACE Clin Case Rep, 2021 02 01;7(3):220-225.
    PMID: 34095493 DOI: 10.1016/j.aace.2021.01.008
    Objective: Primary hypophysitis refers to the isolated inflammation of the pituitary gland not associated with other secondary causes. Among its histopathologic subtypes, xanthomatous is the rarest.

    Methods: We describe a 22-year-old woman with xanthomatous hypophysitis (XH), its clinical progression over 8 years as well as the treatment effects of prednisolone and azathioprine. Our patient was first referred for severe short stature and delayed puberty at the age of 14 years.

    Results: Investigations revealed multiple pituitary deficiencies. Magnetic resonance imaging showed a pituitary mass whereby a partial resection was performed. A full resection was not feasible due to the location of the mass. The histopathologic analysis of the tissue was consistent with XH. The results of secondary workout for neoplasm, infection, autoimmune, and inflammatory disorders were negative. After surgery, a progressive enlargement of the mass was observed. Two courses of prednisolone were administered with a significant reduction in the mass size. Azathioprine was added due to the unsustained effects of prednisolone when tapered off and the concern of steroid toxicity with continued use. No further increase in the mass size was noted after 6 months on azathioprine.

    Conclusion: Glucocorticoid and immunotherapy are treatment options for XH; however, more cases are needed to better understand its pathogenesis and clinical progression.

    Matched MeSH terms: Pituitary Gland
  3. Kuan YC, Nurain MN
    Med J Malaysia, 2017 02;72(1):50-52.
    PMID: 28255140 MyJurnal
    Described herein, a case of Langerhans cell histiocytosis (LCH) in an adult with Idiopathic Thrombocytopenic Purpura (ITP) diagnosed at age ten. She presented with cranial diabetes insipidus, later developed hypogonadotrophic hypogonadism and multiple cervical lympadenopathy from which histopathology of excisional biopsy confirmed LCH. Magnetic resonance imaging showed thickened pituitary stalk. Association of ITP and LCH is unknown but the question of LCH presenting as isolated thrombocytopenia in childhood only to be discovered in adulthood when there was pituitary and bone involvement remains. It reemphasizes the need for high index of suspicion and the challenges in diagnosing LCH at the outset.
    Matched MeSH terms: Pituitary Gland
  4. Ooi CP, Kamarruddin NA, Mustafa N, Kew TY
    J ASEAN Fed Endocr Soc, 2018;33(1):69-73.
    PMID: 33442114 DOI: 10.15605/jafes.033.01.12
    A 58-year-old male presented with persistent severe headache, lethargy, decline libido and no neurological deficits. Besides quadruple anterior pituitary hormonal deficiencies, magnetic resonance imaging (MRI) demonstrated an enlarged ring-enhanced non-homogenous pituitary. Following hormonal replacement, these symptoms improved but empty sella evolved. The challenges of diagnosis and management were discussed. Awareness of the unclear etiology and uncertain clinical course of autoimmune hypophysitis in a man in this age group is essential for prompt and appropriate management.
    Matched MeSH terms: Pituitary Gland
  5. Biran J, Golan M, Mizrahi N, Ogawa S, Parhar IS, Levavi-Sivan B
    Endocrinology, 2014 Dec;155(12):4831-42.
    PMID: 25211586 DOI: 10.1210/en.2013-2114
    Neurokinin B (NKB) was recently identified as a key regulator of reproduction in mammals and fish. Fish were found to possess a specific novel neurokinin termed NKF. To study the role of NKB/NKF in the regulation of fish reproduction and to investigate the role of NKB/NKF and their receptors in the piscine pituitary, we have identified the NKB/tachikinin 3 receptor (tac3r) system in tilapia. Bioinformatics and phylogenetic analyses have demonstrated that the tilapia holds 1 putative tac3 gene and 2 NKB receptor genes (tac3ra and tac3rb) that clustered with other piscine Tac3 and NKB receptor lineages. Furthermore, we found that in African cichlids, NKB peptides differ from other vertebrate NKBs in their C-terminal sequence, possessing isoleucine instead of valine as the X in the NKB FXGLM-NH2-terminal consensus sequence. Signal transduction analysis demonstrated that tilapia NKB (tiNKB), tiNKF, and human NKB activated both CRE-luc and SRE-luc transcriptional activity of both tilapia and human NKB receptors. Two hours after ip injection of tiNKB, the plasma levels of both FSH and LH were increased, whereas tiNKF was more effective in increasing LH levels. However, tiNKB was more effective than tiNKF in increasing both FSH and LH from tilapia pituitary dispersed cells. Using in situ hybridization and fluorescent immunohistochemistry, we have shown that LH cells possess tac3, tac3ra, and tac3rb mRNAs, whereas FSH cells possess mainly tac3rb and tac3ra and tac3 to a much lesser extent. These results suggest that the members of the NKB/tac3r system may serve as paracrine/autocrine regulators of gonadotropin release in fish pituitary.
    Matched MeSH terms: Pituitary Gland/metabolism*
  6. Ogawa S, Sivalingam M, Anthonysamy R, Parhar IS
    Cell Tissue Res, 2020 Feb;379(2):349-372.
    PMID: 31471710 DOI: 10.1007/s00441-019-03089-5
    Kisspeptin is a hypothalamic neuropeptide, which acts directly on gonadotropin-releasing hormone (GnRH)-secreting neurons via its cognate receptor (GPR54 or Kiss-R) to stimulate GnRH secretion in mammals. In non-mammalian vertebrates, there are multiple kisspeptins (Kiss1 and Kiss2) and Kiss-R types. Recent gene knockout studies have demonstrated that fish kisspeptin systems are not essential in the regulation of reproduction. Studying the detailed distribution of kisspeptin receptor in the brain and pituitary is important for understanding the multiple action sites and potential functions of the kisspeptin system. In the present study, we generated a specific antibody against zebrafish Kiss2-R (=Kiss1Ra/GPR54-1/Kiss-R2/KissR3) and examined its distribution in the brain and pituitary. Kiss2-R-immunoreactive cell bodies are widely distributed in the brain including in the dorsal telencephalon, preoptic area, hypothalamus, optic tectum, and in the hindbrain regions. Double-labeling showed that not all but a subset of preoptic GnRH3 neurons expresses Kiss2-R, while Kiss2-R is expressed in most of the olfactory GnRH3 neurons. In the posterior preoptic region, Kiss2-R immunoreactivity was seen in vasotocin cells. In the pituitary, Kiss2-R immunoreactivity was seen in corticotropes, but not in gonadotropes. The results in this study suggest that Kiss2 and Kiss2-R signaling directly serve non-reproductive functions and indirectly subserve reproductive functions in teleosts.
    Matched MeSH terms: Pituitary Gland/metabolism
  7. Chung WH, Chiu CK, Wei Chan CY, Kwan MK
    Acta Orthop Traumatol Turc, 2020 Sep;54(5):561-564.
    PMID: 33155569 DOI: 10.5152/j.aott.2020.19144
    Growth hormone secreting pituitary tumor or gigantism has not been previously reported to be associated with rapid progression of scoliosis in the literature. However, there are some reports indicating scoliosis can be worsened by growth hormone therapy in children and adolescents. A 19-year-old boy was referred to our institution for the treatment of a right thoracolumbar scoliosis. The Cobb angle had worsened from 29° to 83° over two years' duration. He attained puberty at the age of 13. He had a previous history of slipped upper femoral epiphysis (SUFE), which was operated in 2015, with no clinical features of gigantism. Preoperative assessment was performed. He was diagnosed with growth hormone secreting pituitary macroadenoma by magnetic resonance imaging with a high serum level of insulin-like growth factor-I (IGF-I). Computed tomography (CT) of the pancreas showed a pancreatic endocrine tumor. The patient was later diagnosed with multiple endocrine neoplasia type 1 (MEN 1). He underwent endoscopic endonasal excision of the pituitary mass and distal pancreatectomy. This case indicates that growth hormone secreting pituitary macroadenoma could result in rapid progression of scoliosis.
    Matched MeSH terms: Pituitary Gland/surgery
  8. Wan Muhamad Hatta SF, Hamdan MF, Md Ali SA, Abdul Ghani R
    BMJ Case Rep, 2016 Sep 09;2016.
    PMID: 27613264 DOI: 10.1136/bcr-2016-216395
    Idiopathic granulomatous hypophysitis (GH) is an uncommon inflammatory disease of the pituitary with impairment of pituitary gland function due to infiltration by lymphocytes, plasma cells and macrophages. We report the case of a 39-year-old woman who presented with worsening of headaches for 1 month and blurring of vision over 5 days. An MRI revealed a homogeneous supra-sellar mass evoking a pituitary tumour with bulky pituitary stalk extending into the left and right cavernous sinuses. Hormonal investigations showed anterior pituitary hormone deficiencies; meanwhile histopathological examination revealed an aspect of hypophysitis. Clinical and radiological remission occurred immediately postglucocorticoid therapy with the addition of a steroid-sparing agent later in view of recurrence of symptoms on glucocorticoid dose reduction. GH has important diagnostic and therapeutic implications, as clinical and radiological features ameliorate via medical treatment. With further understanding and recognition of the disease, we hope to highlight a case of GH, in which signs and symptoms improved after initiation of corticosteroids.
    Matched MeSH terms: Pituitary Gland/pathology*
  9. Jayachandra S, D'Souza UJ
    J Environ Sci Health B, 2014;49(4):271-8.
    PMID: 24502214 DOI: 10.1080/03601234.2014.868287
    The objective of this research is to study the possible reproductive adverse effects of diazinon on rat offspring exposed in utero and during lactation. Twenty-four Sprague-Dawley female rats (10-12 week old) were randomly assigned to four groups, each consisting of six rats. Group 1 served as the control and these rats were given normal saline orally. Rats in groups 2, 3, and 4 were administered diazinon, dissolved in saline at 10, 15, 30 mg/ kg(-1) body weight, per oral, once daily, during mating, pregnancy and lactation. The male offsprings were examined at puberty and adulthood for body weight, testis weight, epididymis weight, sperm count, motility and morphology, pituitary-gonadal hormone levels. At 30 mg kg(-1) dose, the male offsprings showed a decrease in testicular weight, sperm count, motility, with an increase in abnormal sperm percentage and a decline in pituitary-gonadal hormones, at puberty. Upon attaining adulthood, there was a decrease in testicular weight, sperm count and motility with an increase in abnormal sperm percentage and a decrease in pituitary hormone level. There was evidence of some adverse reproductive effects on the male offspring at the 15 mg/ kg(-1) dose. Most of the adverse effects were irreversible and were evident at both puberty and adulthood in the offsprings, although a few parameters reverted to the normal growth pattern. Diazinon is a reproductive toxicant for male offsprings if exposed during prenatal and postnatal phases.
    Matched MeSH terms: Pituitary Gland/drug effects; Pituitary Gland/metabolism
  10. Li G, Tang H, Chen Y, Yin Y, Ogawa S, Liu M, et al.
    Mol Cell Endocrinol, 2018 02 05;461:1-11.
    PMID: 28801227 DOI: 10.1016/j.mce.2017.08.003
    The LHb expression is up-regulated during puberty in female zebrafish. However, the molecular mechanism underlying how LHb expression is regulated during puberty remains largely unknown. In this study, we found that the mRNA expression levels of lhb, fshb and cyp19a1b were up-regulated along with the puberty onset in zebrafish. Among the three nuclear estrogen receptors (nERs), the esr2b is the only type whose expression is significantly up-regulated during puberty onset in the pituitary. However, in situ hybridization results revealed that lhb mRNA was colocalized with esr1 and esr2a but not esr2b. Exposure to estradiol (E2) significantly stimulates LHb expression in both wild-type and kiss1-/-;kiss2-/-;gnrh3-/- triple knockout pubertal zebrafish. Moreover, exposure of cultured pituitary cells to E2 increased the LHb expression, indicating that the estrogenic effect on LHb expression could be acted at the pituitary level. Finally, we cloned and analyzed the promoter of lhb by luciferase assay. Our results indicated that the E2 responsive regions of lhb promoter for ERα and ERβ2 are identical, suggesting that ERα and ERβ2 could bind to the same half ERE region of the promoter of lhb, exhibiting a classical ERE-dependent pathway. In summary, we demonstrate that E2 could directly act on the pituitary level to stimulate LHb transcription during puberty in zebrafish.
    Matched MeSH terms: Pituitary Gland/drug effects; Pituitary Gland/metabolism*
  11. Maneesh M, Dutta S, Chakrabarti A, Vasudevan DM
    Indian J. Physiol. Pharmacol., 2006 Jul-Sep;50(3):291-6.
    PMID: 17193902
    Ethanol is a testicular toxin and it causes fertility abnormalities with low sperm count and impaired sperm motility in men. The present study was designed to investigate plasma testosterone level and hypothalamic pituitary gonadal (HPG) axis function in alcoholic men and also effect of ethanol on systemic oxidative stress. Forty six male alcohol abusers in the age group 20-40 years were selected. Fifty five, males in the same age group served as control. Alcohol abusers had significantly low plasma testosterone with low luteinizing hormone and follicle stimulating hormone. In addition they had significantly high thiobarbituric acid reactive substances (TBARS), superoxide dismutase and glutathione S-transferase, and low glutathione, ascorbic acid, catalase, glutathione reductase and glutathione peroxidase. Moreover, serum testosterone level in alcoholics negatively correlated with duration of alcohol abuse, and TBARS. Duration dependent decreased serum testosterone level in alcohol abusers might be due to 1) increased oxidative stress which can damage Leydig and supporting Sertoli cells and 2) impaired HPG axis.
    Matched MeSH terms: Pituitary Gland/metabolism
  12. Tay PYS, Lenton EA
    Med J Malaysia, 2003 Jun;58(2):187-95.
    PMID: 14569738
    A prospective randomised study was done to assess the effect of supplemental oestradiol in addition to progesterone on the luteal steroid profiles and pregnancy outcome in stimulated cycles with and without pituitary down regulation. Women undergoing stimulated cycle IVF with GnRH-a and FSH (Group A, n = 63) or stimulated intrauterine insemination using CC and FSH (Group B, n = 55) were studied. These subjects were randomly allocated to receive either 400 mg daily of vaginally administrated Cyclogest (progesterone) alone or in combination with 2 mg daily of oral Oestradiol Valerate (E2V) during the luteal phase. Significant lower concentrations of plasma progesterone were observed in those subjects supplemented with both E2V and progesterone compared to those in whom progesterone only was given during the luteal phase (P < 0.05). Exogenous E2V had a minimal impact on plasma oestradiol concentrations and did not disguise the characterised mid luteal decline in oestradiol secretion. The suppressive effect of E2V on plasma progesterone was lost if implantation occurred normally because any small change in steroid concentrations was reversed by the rapidly increasing concentrations of HCG. Similar pregnancy rates were observed among subjects supplemented with or without oestradiol. The addition of oestradiol to the luteal supplement suppresses endogenous corpus luteum progesterone secretion irrespective of the type of assisted conception cycle and that its use is unlikely to be beneficial to the process of implantation.
    Matched MeSH terms: Pituitary Gland/metabolism
  13. Greenwood MP, Greenwood M, Romanova EV, Mecawi AS, Paterson A, Sarenac O, et al.
    Neurobiol Aging, 2018 05;65:178-191.
    PMID: 29494864 DOI: 10.1016/j.neurobiolaging.2018.01.008
    Elderly people exhibit a diminished capacity to cope with osmotic challenges such as dehydration. We have undertaken a detailed molecular analysis of arginine vasopressin (AVP) biosynthetic processes in the supraoptic nucleus (SON) of the hypothalamus and secretory activity in the posterior pituitary of adult (3 months) and aged (18 months) rats, to provide a comprehensive analysis of age-associated changes to the AVP system. By matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, we identified differences in pituitary peptides, including AVP, in adult and aged rats under both basal and dehydrated states. In the SON, increased Avp gene transcription, coincided with reduced Avp promoter methylation in aged rats. Based on transcriptome data, we have previously characterized a number of novel dehydration-induced regulatory factors involved in the response of the SON to osmotic cues. We found that some of these increase in expression with age, while dehydration-induced expression of these genes in the SON was attenuated in aged rats. In summary, we show that aging alters the rat AVP system at the genome, transcriptome, and peptidome levels. These alterations however did not affect circulating levels of AVP in basal or dehydrated states.
    Matched MeSH terms: Pituitary Gland, Posterior/secretion
  14. Jesse FF, Ibrahim HH, Abba Y, Chung EL, Marza AD, Mazlan M, et al.
    BMC Vet Res, 2017 Apr 05;13(1):88.
    PMID: 28381248 DOI: 10.1186/s12917-017-1010-y
    BACKGROUND: Hemorrhagic septicemia is a fatal disease of cattle and buffaloes caused by P. multocida. Although the pathogenesis of the bacteria has been well established in literature, there is a paucity of information on the possible role of the bacteria and its immunogens; lipopolysaccharide (LPS) and outer membrane proteins (OMPs) on the reproductive capacity of buffalo heifers.

    METHODS: In this study, twenty one healthy prepubertal female buffaloes aged 8 months were divided into seven groups of 3 buffaloes each (G1-G7). Group 1 (G1) served as the negative control group and were inoculated orally with 10 mL sterile Phosphate Buffer Saline (PBS), groups 2 (G2) and 3 (G3) were inoculated orally and subcutaneously with 10 mL of 10(12) colony forming unit (cfu) of P.multocida type B: 2, while groups 4 (G4) and 5 (G5) received 10 mL of bacterial LPS orally and intravenously, respectively. Lastly, groups 6 (G6) and 7 (G7) were orally and subcutaneously inoculated with 10 mL of bacterial OMPs. Whole blood was collected in EDTA vials at stipulated time points (0, 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, 120, 168, 216, 264, 312, 360, 408, 456 and 504 h), while tissue sections of the pituitary glands were collected and transported to the histopathology laboratory in 10% buffered formalin for processing and Hematoxylin and eosin staining. Plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone (PG), estradiol (EST) and gonadotrophin releasing hormone (GnRH) were determined.

    RESULTS: The histopathological lesions observed in the pituitary gland included hemorrhage, congestion, inflammatory cell infiltration, hydropic degeneration, necrosis and edema. These changes were higher (p 

    Matched MeSH terms: Pituitary Gland/pathology
  15. Thomas FSK, Higuchi Y, Ogawa S, Soga T, Parhar IS
    Peptides, 2021 04;138:170504.
    PMID: 33539873 DOI: 10.1016/j.peptides.2021.170504
    Stress impairs the hypothalamic-pituitary-gonadal (HPG) axis, probably through its influence on the hypothalamic-pituitary-adrenal (= interrenals in the teleost, HPI) axis leading to reproductive failures. In this study, we investigated the response of hypothalamic neuropeptides, gonadotropin-inhibitory hormone (GnIH), a component of the HPG axis, and corticotropin-releasing hormone (CRH) a component of the HPI axis, to acute social defeat stress in the socially hierarchical male Nile tilapia (Oreochromis niloticus). Localization of GnIH cell bodies, GnIH neuronal processes, and numbers of GnIH cells in the brain during acute social defeat stress was studied using immunohistochemistry. Furthermore, mRNA levels of GnIH and CRH in the brain together with GnIH receptor, gpr147, and adrenocorticotropic hormone (ACTH) in the pituitary were quantified in control and socially defeated fish. Our results show, the number of GnIH-immunoreactive cell bodies and GnIH mRNA levels in the brain and the levels of gpr147 mRNA in the pituitary significantly increased in socially defeated fish. However, CRH and ACTH mRNA levels did not change during social defeat stress. Further, we found glucocorticoid type 2b receptor mRNA in laser captured immunostained GnIH cells. These results show that acute social defeat stress activates GnIH biosynthesis through glucocorticoid receptors type 2b signalling but does not change the CRH and ACTH mRNA expression in the tilapia, which could lead to temporary reproductive dysfunction.
    Matched MeSH terms: Pituitary Gland/metabolism
  16. Haydar Ali Tajuddin A, Kamaruddin N, Sukor N, Azizan EA, Omar AM
    J Endocr Soc, 2020 Dec 01;4(12):bvaa157.
    PMID: 33241169 DOI: 10.1210/jendso/bvaa157
    Estrogen (17β-estradiol or E2) is a crucial regulator of the synthesis and secretion of pituitary reproductive hormones luteinizing hormone, follicle-stimulating hormone, and prolactin. In this review, we summarize the role of estrogen receptors in nonfunctioning pituitary neuroendocrine tumors (NF-Pitnets), focusing on immunoexpression and gonadotroph cell proliferation and apoptosis. Gonadotroph tumors are the most common subtype of NF-Pitnets. Two major estrogen receptor (ER) isoforms expressed in the pituitary are estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Overall, estrogen actions are mostly exerted through the ERα isoform on the pituitary. The G protein-coupled estrogen receptor (GPER) located at the plasma membrane may contribute to nongenomic effects of estrogen. Nuclear immunoreactivity for ERα and ERβ was highest among gonadotroph and null cell tumors. Silent corticotroph tumors are the least immunoreactive for both receptors. A significantly elevated ERα expression was observed in macroadenomas compared with microadenomas. ERα and ERβ may act in opposite directions to regulate the Slug-E-cadherin pathway and to affect invasiveness of NF-Pitnets. In the cellular pathway, ERs regulate estrogen-induced proliferation and differentiation and impact several signaling pathways including the MAPK and PI3K/Akt pathway. Estrogen was the first-discovered inducer of pituitary tumor transforming gene 1 that was abundantly expressed in NF-Pitnets. ERα can be a potential biomarker for predicting tumor size and invasiveness as well as therapeutic target for NF-Pitnets. Selective estrogen receptor modulators or antiestrogen may represent as an alternative choice for the treatment of NF-Pitnets.
    Matched MeSH terms: Pituitary Gland
  17. Mizrahi N, Gilon C, Atre I, Ogawa S, Parhar IS, Levavi-Sivan B
    PMID: 31354632 DOI: 10.3389/fendo.2019.00469
    Neurokinin B (NKB) and its cognate receptor (NK3R) are emerging as important components of the neuroendocrine regulation of reproduction. Unlike mammalian tac3, which encodes only one mature peptide (namely NKB), two mature peptides are predicted for each tac3 gene in fish and frogs. Therefore, it was designated as Neurokinin F (NKF). Hormone analogs with high and long-lasting biological activity are important tools for physiological and biological research; however, the availability of piscine-specific analogs is very limited. Therefore, we have developed specific NKB and NKF analogs based on the structure of the mammalian NKB analog-senktide. These analogs, specifically designed for longer half-lives by methylation of proteolysis sites, exhibited activity equal to those of the native NKB and NKF in short-term signal-transduction assays of tilapia NKB receptors. However, the analogs were found to be able to significantly increase the release of luteinizing hormone (LH), follicle stimulating hormone (FSH) and growth hormone (GH) in tilapia, as fast as 1 h after intraperitoneal (IP) injection. The impact of the analogs on LH and FSH secretion lasted longer compared to the effect of native peptides and salmon GnRH analog (sGnRHa). In addition, we harvested pituitaries 24 h post injection and measured LH, FSH and GH mRNA synthesis. Both analogs elevated mRNA levels of LH and GH, but only NKB analog increased FSH mRNA levels in the pituitary and all GnRH forms in the brain. NKB receptors were co-localized with all three types the GnRH neurons in tilapia brain in situ. We previously showed a direct effect of NKB at the pituitary level, and these new results suggest that the stronger impact of the NKB analog on GTH release is also due to an indirect effect through the activation of GnRH neurons. These results suggest that novel synthetic NKB analogs may serve as a tool for both research and agricultural purposes. Finally, the biological activity and regulatory role of NKB in tilapia brain and pituitary suggest that the NKB/NKBR system in fish is an important reproductive regulator in a similar way to the kisspeptin system in mammals.
    Matched MeSH terms: Pituitary Gland
  18. Elyasi Gorji Z, Amiri-Yekta A, Gourabi H, Hassani S, Fatemi N, Zerehdaran S, et al.
    Iran J Biotechnol, 2015 Jun;13(2):10-17.
    PMID: 28959285 DOI: 10.15171/ijb.1004
    BACKGROUND: Follicle stimulating hormone (FSH) plays an essential role in reproductive physiology and follicular development.

    OBJECTIVE: A new variant of the equine fsh (efsh) gene was cloned, sequenced, and expressed in Pichia pastoris (P. pastoris) GS115 yeast expression system.

    MATERIALS AND METHODS: The full-length cDNAs of the efshα and efshβ chains were amplified by reverse transcription polymerase chain reaction (RT-PCR) using the total RNA isolated from an Iranian Turkmen-thoroughbred horse's anterior pituitary gland. The amplified efsh chains were cloned into the pPIC9 vector and transferred into P. pastoris. The secretion of recombined eFSH using P. pastoris expression system was confirmed by Western blotting and immunoprecipitation (IP) methods.

    RESULTS: The DNA sequence of the efshβ chain accession number JX861871, predicted two putative differential nucleotide arrays, both of which are located in the 3'UTR. Western blotting showed a molecular mass of 13 and 18 kDa for eFSHα and eFSHβ subunits, respectively. The expression of desired protein was confirmed by protein G immunoprecipitation kit.

    CONCLUSIONS: eFSH successfully expressed in P. pastoris. These findings lay a foundation to improve ovulation and embryo recovery rates as well as the efficiency of total embryo-transfer process in mares.

    Matched MeSH terms: Pituitary Gland, Anterior
  19. Ng KY, Leong MK, Liang H, Paxinos G
    Brain Struct Funct, 2017 Sep;222(7):2921-2939.
    PMID: 28478550 DOI: 10.1007/s00429-017-1439-6
    Melatonin, through its different receptors, has pleiotropic functions in mammalian brain. Melatonin is secreted mainly by the pineal gland and exerts its effects via receptor-mediated and non-receptor-mediated actions. With recent advancement in neuroanatomical mapping, we may now understand better the localizations of the two G protein-coupled melatonin receptors MT1 and MT2. The abundance of these melatonin receptors in respective brain regions suggests that receptor-mediated actions of melatonin might play crucial roles in the functions of central nervous system. Hence, this review aims to summarize the distribution of melatonin receptors in the brain and to discuss the putative functions of melatonin in the retina, cerebral cortex, reticular thalamic nucleus, habenula, hypothalamus, pituitary gland, periaqueductal gray, dorsal raphe nucleus, midbrain and cerebellum. Studies on melatonin receptors in the brain are important because cumulative evidence has pointed out that melatonin receptors not only play important physiological roles in sleep, anxiety, pain and circadian rhythm, but might also be involved in the pathogenesis of a number of neurodegenerative diseases including Alzheimer's disease, Parkinson's disease and Huntington's disease.
    Matched MeSH terms: Pituitary Gland
  20. Abdullah NRA, Jason WLC, Nasruddin AB
    PMID: 28567291 DOI: 10.1530/EDM-17-0029
    Pachydermoperiostosis is a very rare osteoarthrodermopathic disorder whose clinical and radiographic presentations may mimic those of acromegaly. In the evaluation of patients with acromegaloid appearances, pachydermoperiostosis should be considered as a differential diagnosis. In this article, we report a 17-year-old boy who presented with 2-year history of acral enlargement and facial appearance changes associated with joint pain and excessive sweating. He had been investigated extensively for acromegaly, and the final diagnosis was pachydermoperiostosis.

    LEARNING POINTS: There is a broad range of differential diagnosis for acromegaloid features such as acromegaly, pseudoacromegaly with severe insulin resistance, Marfan's syndrome, McCune-Albright and a rare condition called pachydermoperiostosis.Once a patient is suspected to have acromegaly, the first step is biochemical testing to confirm the clinical diagnosis, followed by radiologic testing to determine the cause of the excess growth hormone (GH) secretion. The cause is a somatotroph adenoma of the pituitary in over 95 percent of cases.The first step is measurement of a serum insulin-like growth factor 1 (IGF1). A normal serum IGF1 concentration is strong evidence that the patient does not have acromegaly.If the serum IGF1 concentration is high (or equivocal), serum GH should be measured after oral glucose administration. Inadequate suppression of GH after a glucose load confirms the diagnosis of acromegaly.Once the presence of excess GH secretion is confirmed, the next step is pituitary magnetic resonance imaging (MRI).Atypical presentation warrants revision of the diagnosis. This patient presented with clubbing with no gigantism, which is expected in adolescent acromegalics as the growth spurt and epiphyseal plate closure have not taken place yet.

    Matched MeSH terms: Pituitary Gland
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