Gonadotropin-releasing hormone II (GnRH II) mediates the anorexigenic actions of α-melanocyte-stimulating hormone (α-MSH) and corticotropin-releasing hormone (CRH) in goldfish

Intracerebroventricular (ICV) administration of gonadotropin-releasing hormone II (GnRH II), which plays a crucial role in the regulation of reproduction in vertebrates, markedly reduces food intake in goldfish. However, the neurochemical pathways involved in the anorexigenic action of GnRH II and its interaction with other neuropeptides have not yet been identified. Alpha-melanocyte-stimulating hormone (α-MSH), corticotropin-releasing hormone (CRH) and CRH-related peptides play a major role in feeding control as potent anorexigenic neuropeptides in goldfish. However, our previous study has indicated that the GnRH II-induced anorexigenic action is not blocked by treatment with melanocortin 4 receptor (MC4R) and CRH receptor antagonists. Therefore, in the present study, we further examined whether the anorexigenic effects of α-MSH and CRH in goldfish could be mediated through the GnRH receptor neuronal pathway. ICV injection of the MC4R agonist, melanotan II (80 pmol/g body weight; BW), significantly reduced food intake, and its anorexigenic effect was suppressed by ICV pre-administration of the GnRH type I receptor antagonist, antide (100 pmol/g BW). The CRH-induced (50 pmol/g BW) anorexigenic action was also blocked by treatment with antide. ICV injection of CRH (50 pmol/g BW) induced a significant increase of the GnRH II mRNA level in the hypothalamus, while ICV injection of melanotan II (80 pmol/g BW) had no effect on the level of GnRH II mRNA. These results indicate that, in goldfish, the anorexigenic actions of α-MSH and CRH are mediated through the GnRH type I receptor-signaling pathway, and that the GnRH II system regulates feeding behavior.     

Effects of juvenile hormone I and the anti-juvenile hormone fluoromevalono-lactone on development and juvenile hormone esterase activity in post-feeding last-stadium larvae of Trichoplusia ni (Hübner)

Treatment of post-feeding (early day 3; wandering phase) last-stadium larvae of the cabbage looper, Trichoplusia ni, with the anti-juvenile hormone, fluoromevalonolactone, prevented the normal ecdysis to the pupa. It caused the formation of larval-pupal intermediates, a dose-dependent delay in the time of tanning, and a decrease in juvenile hormone esterase activity at the time of the prepupal juvenile hormone esterase peak. Fluoromevalonolactone was inactive as juvenile hormone esterase inhibitor in vitro. Conversely, juvenile hormone I accelerated the time of tanning, induced the early appearance of juvenile hormone esterase activity, and prevented adult eclosion. Although most of the larvae that were treated with fluoromevalonolactone immediately after the prepupal burst of juvenile hormone (late on day 3; post-spinning phase) still became larval-pupal intermediates, the time of tanning and juvenile hormone esterase activity were close to normal. Topical treatment of day-3 larvae with radiolabelled juvenile hormone I resulted in the rapid appearance and decline of radiolabelled juvenile hormone I in the haemolymph which was associated with the increased production of juvenile hormone I acid and the induced appearance of juvenile hormone esterase activity. Thus, in post-feeding last-stadium larvae of T. ni, juvenile hormone seems to be necessary for the proper formation of the pupa. Juvenile hormone is also involved in determining the time of pupation, and it appears to induce its own degradation.     

Potential role of follicle-stimulating hormone (FSH) and transforming growth factor (TGFβ1) in the regulation of ovarian angiogenesis

Angiogenesis occurs during ovarian follicle development and luteinization. Pituitary secreted FSH was reported to stimulate the expression of endothelial mitogen VEGF in granulosa cells. And, intraovarian cytokine transforming growth factor (TGF)β1 is known to facilitate FSH‐induced differentiation of ovarian granulosa cells. This intrigues us to investigate the potential role of FSH and TGFβ1 regulation of granulosa cell function in relation to ovarian angiogenesis. Granulosa cells were isolated from gonadotropin‐primed immature rats and treated once with FSH and/or TGFβ1 for 48 h, and the angiogenic potential of conditioned media (granulosa cell culture conditioned media; GCCM) was determined using an in vitro assay with aortic ring embedded in collagen gel and immunoblotting. FSH and TGFβ1 increased the secreted angiogenic activity in granulosa cells (FSH + TGFβ1 > FSH ≈ TGFβ1 > control) that was partly attributed to the increased secretion of pro‐angiogenic factors VEGF and PDGF‐B. This is further supported by the evidence that pre‐treatment with inhibitor of VEGF receptor‐2 (Ki8751) or PDGF receptor (AG1296) throughout or only during the first 2‐day aortic ring culture period suppressed microvessel growth in GCCM‐treated groups, and also inhibited the FSH + TGFβ1‐GCCM‐stimulated release of matrix remodeling‐associated gelatinase activities. Interestingly, pre‐treatment of AG1296 at late stage suppressed GCCM‐induced microvessel growth and stability with demise of endothelial and mural cells. Together, we provide original findings that both FSH and TGFβ1 increased the secretion of VEGF and PDGF‐B, and that in turn up‐regulated the angiogenic activity in rat ovarian granulosa cells. This implicates that FSH and TGFβ1 play important roles in regulation of ovarian angiogenesis during follicle development. J. Cell. Physiol. 226: 1608–1619, 2011. © 2010 Wiley‐Liss, Inc.     

Structural studies of α-melanocyte-stimulating hormone and a novel β-melanocyte-stimulating hormone from the neurointermediate lobe of the pituitary of the dogfish Squalus acanthias

A melanocyte-stimulating hormone (MSH) has been isolated from extracts of the neurointermediate lobe of the pituitary of the dogfish Squalus acanthias by gel-filtration and ion-exchange chromatography. It had approximately 1% of the potency of mammalian alpha-MSH on bioassays in vitro on frog skin and dogfish skin. Sequence analysis revealed it to be a hexadecapeptide with the following primary structure: Asp-Gly-Asp-Asp-Tyr-Lys-Phe-Gly-His-Phe-Arg-Trp-Ser-Val-Pro-Leu. It appears to be related to the beta-MSH species of mammalian species but has only the sequence -His-Phe-Arg-Trp- in common with the heptapeptide core -Met-Glu-His-Phe-Arg-Trp-Gly- which is characteristic not only of the MSH peptides but also of the adrenocorticotrophins and lipotrophins studied so far. An alpha-MSH was also isolated, 50% of which was amidated at the C-terminus group. Sequence data from this study taken in conjunction with those from a previous study (Lowry & Chadwick, 1970b) revealed it to be a tridecapeptide which is identical with the N-terminal sequence of dogfish adrenocorticotrophin.     

Expression of anti-Müllerian hormone (AMH) in the equine testis

Anti-Müllerian hormone (AMH) induces regression of Müllerian ducts during male fetal development; in the human male, it is expressed in Sertoli cells during fetal development (and through puberty). The objective was to characterize expression of AMH in the fetal, neonatal, prepubertal, and adult equine testis, as well as in equine cryptorchid testes, in select testicular neoplasms, and in intersex gonads, based upon immunohistochemistry (IHC). Testes were removed from equine fetuses at 5.5, 10, and 11 months of gestation, at 12 months of age, and from adult stallions. In addition, cryptorchid testes, testis tumors (teratomas, seminomas, Sertoli cell tumors), and male intersex gonads were examined by IHC for expression of AMH using a goat polyclonal primary antibody (alpha-AMH) directed against a C-terminal peptide antigen from human AMH. Immunolabeling with alpha-AMH was localized to Sertoli cells within the developing seminiferous tubules of fetal, neonatal and prepubertal equine testes, with no expression detected in Sertoli cells from normal adult equine testes. Furthermore, expression was detected in cryptorchid testes (in animals up to 3-4 years of age) and in Sertoli cell tumors and male intersex gonads. In conclusion, AMH was strongly expressed by Sertoli cells in fetal, neonatal and prepubertal equine testes, but not in normal adult testes. That AMH was expressed in cryptorchid testes may provide a useful biomarker for detection of cryptorchid testes, as well as for immunohistochemical characterization of testicular tumors and intersex gonads in the horse.     

Immunocytochemical localization of POMC-derived peptides (adrenocorticotropic hormone, α-melanocyte-stimulating hormone and β-endorphin) in the pituitary,brain and olfactory epithelium of the frog,Rana esculenta,during development

Developmental stages of Rana esculenta, starting with the posterior limb-bud stage (stage 26) up to a few days after metamorphosis, were examined immunohistochemically to localize cells and fibers producing some POMC-derived peptides, namely, -MSH, ACTH and -END. Anti ACTH and anti -MSH revealed a positive reaction in the pars intermedia during all stages of development included in this study, whereas no immunoreactivity in this pituitary zone was ever evidenced with anti -END. In the pars distalis strongly positive cells were seen with anti ACTH and anti -END, while anti -MSH yielded weakly positive cells. Interestingly, these peptides were colocalized in the same cells. Immunoreactivity for -MSH was no longer present in the pars distalis during metamorphic climax and postmetamorphosis. In the brain of premetamorphic tadpoles, belonging to stages 26 to 30, a few neurons in the posterior telencephalon showed a positive reaction only with anti -MSH,but from stage 31 (prometamorphosis) onwards, ACTH and -endorphin-like peptide producing cells, together with -MSH-immunoreactive cells, were seen in this region and in the anterior preoptic area and infundibulum. This situation persisted in the subsequent stages of development. Anti -MSH also revealed weakly positive cells in the olfactory epithelium in premetamorphic tadpoles; strong immunoreactivity with anti -MSH was seen in olfactory epithelium cells in animals during prometamorphosis, metamorphic climax and postmetamorphosis. The possible significance of these findings is briefly discussed.     

Paracoccidioidomycosis in the region of Botucatu (state of São Paulo,Brazil). Evaluation of serum thyroxine (T4) and triiodothyronine (T3) levels and of the response to thyrotropin releasing hormone (TRH)

T₄, T₃ and TSH serum levels were measured in 25 patients with paracoccidioidomycosis. Thyroid T₃ reserves were measured on the basis of the increase in T₃ (T₃) 2 h after intravenous injection of 200 g TRH, and pituitary TSH reserves were measured on the basis of TSH increase (TSH) 20 min after the same injection. Twenty healthy volunteers with no history of thyroid disease were used as controls. When the two groups were compared, the following results were obtained: (a) there was no significant difference in mean T₄, T₃, TSH between groups; (b) reduced T₃ levels were detected more frequently in patients with paracoccidioidomycosis, especially among those with the acute form of the disease or with the severely disseminated chronic form. The results suggest the occurrence of a reduction in peripheral conversion of T₄ to T₃, but do not indicate the occurrence of hypothyroidism in any of its forms (thyroid, pituitary or hypothalamic).     

Phylogeny of the Alismatales (Monocotyledons) and the relationship of Acorus (Acorales?)

A phylogenetic analysis of the early branching lineages of the monocotyledons is performed using data from two plastid genes (rbcL and matK), five mitochondrial genes (atp1, ccmB, cob, mttB and nad5) and morphology. The complete matrix includes 93 terminals representing Acorus, the 14 families currently recognized within Alismatales, and numerous lineages of monocotyledons and other angiosperms. Total evidence analysis results in an almost completely resolved strict consensus tree, but all data partitions, genomic as well as morphological, are incongruent. The effects of RNA editing and potentially processed paralogous sequences are explored and discussed. Despite a decrease in incongruence length differences after exclusion of edited sites, the major data partitions remain significantly incongruent. The 14 families of Alismatales are all found to be monophyletic, but Acorus is found to be included in Alismatales rather than being the sister group to all other monocotyledons. The placement is strongly supported by the mitochondrial data, atp1 in particular, but it cannot be explained as an artifact caused by patterns of editing or by sampling of processed paralogues.     

Discordances between follicle stimulating hormone (FSH) and anti-Müllerian hormone (AMH) in female infertility

Background

Follicle stimulating hormone (FSH) and anti-Müllerian hormone (AMH) represent the two most frequently utilized laboratory tests in determining ovarian reserve (OR). This study determined the clinical significance of their concordance and discordance in female infertility patients.

Methods

We investigated 366 consecutive infertility patients (350 reached IVF), excluding women with polycystic ovarian syndrome (PCOS). They were considered to have normal FSH and AMH if values fell within age-specific (as-) 95% confidence intervals (CI), and to suffer from diminished ovarian reserve (DOR) if FSH exceeded and/or AMH fell below those. The two hormones, thus, could be concordant (Group I), both normal (IA) or abnormal (IB), show normal AMH/abnormal FSH (Group II) or normal FSH/abnormal AMH (Group III). Oocyte yields, stratified for age categories, were then studied in each group as reflection of OR.

Results

Oocyte yields significantly decreased from groups IA to II to III and IB. Predictive values of as-FSH/AMH patterns changed, however, at different ages. Except at very young and very old ages, normal as-AMH better predicted higher oocytes yields than normal as-FSH, though above age 42 years normal as-FSH predicts good oocyte yields even with abnormally low AMH. Under age 42 discrepancies between as- FSH and as-AMH remain similarly predictive of oocyte yields at all ages.

Discussion

Concordances and discordances between as-FSH and as-AMH improve OR assessments and predictability of oocyte yields in IVF.

     

Hormones for life? Behind the rise and fall of a hormone remedy (Gonadex) against sterility in the Swedish welfare state

In 1948 the pharmaceutical company Leo launched a placental hormonal preparation, called Gonadex, in Sweden. During a press conference, and in commercials and newspapers, it was said that Gonadex could cure sterility as well as many other problems related to the endocrine system. The remedy was described as effective and pure, with no side effects whatsoever. For several reasons, Gonadex was looked upon as a 'Swedish triumph'. Inspired by research on 'mediation', conducted within the field of social studies of pharmaceutical drugs, the present essay explores the political and scientific visions and values behind Gonadex; the propaganda for and marketing of Gonadex; the mediated image of Gonadex in the press; the reception by the medical profession, and finally the hopes and fears of the women who tried (or wanted to try) Gonadex. The essay argues that the public image of Gonadex was 'oversell' of hormone therapy, and that it was shaped by the way endocrinologists at Karolinska Hospital, notably Professor Axel Westman, mediated between Leo, the mass media, and the consumers when, and even before, Gonadex was introduced to the market.     

Influence of age and gender on secretion of anti-Müllerian hormone in Asian (Elephas maximus) and African (Loxodonta africana) elephants

Anti-Müllerian hormone (AMH) secretion was studied in Asian and African elephants varying in age and reproductive status. Overall mean concentrations did not differ (P > 0.05) between species, but were markedly higher in male than female Asian elephants (31.01 ± 4.22 ng/mL and 0.19 ± 0.02 ng/mL, mean ± SEM) and African elephants (40.27 ± 3.18 ng/mL, 0.17 ± 0.04 ng/mL), respectively. Anti-Müllerian hormone secretion was not significantly affected by ovarian cyclicity status (cycling vs noncycling), but was higher (P < 0.05) in prepubertal (0.40 ± 0.10 ng/mL) than reproductive age (8-35 y; 0.18 ± 0.04 ng/mL) and aged (≥ 36 y; 0.16 ± 0.03 ng/mL) females. In males, AMH secretion was not significantly affected by musth status, but was age-related, with higher concentrations (P > 0.05) in prepubertal (49.08 ± 6.11 ng/mL) as compared to aged (≥36 y; 22.27 ± 5.82 ng/mL) bulls; concentrations in mature bulls (8-35 y; 37.01 ± 3.17 ng/mL) were similar to prepubertal and older bulls. We concluded that circulating AMH concentrations in elephants were similar between species and not affected by reproductive status; however, concentrations were significantly higher in males than females, and in younger animals. The diagnostic value of AMH to assess fertility status of individual elephants remains to be determined.     

Immunocytochemical localization and ontogenic development of α-melanocyte-stimulating hormone (α-MSH) in the brain of a pleuronectiform fish,barfin flounder

-Melanocyte-stimulating hormone (-MSH) is a pituitary hormone derived by post-translational processing from proopiomelanocortin and is involved in background adaptation in teleost fish. It has also been reported to suppress food intake in mammals. Here, we examined the immunocytochemical localization of -MSH in the brain and pituitary of a pleuronectiform fish, the barfin flounder (Verasper moseri), as a first step in unraveling the possible function of -MSH in the brain. The ontogenic development of the -MSH system was also studied. In the pituitary, -MSH-immunoreactive (ir) cells were preferentially detected in the pars intermedia. In the brain, -MSH-ir neuronal somata were located in the nucleus tuberis lateralis of the basal hypothalamus, and -MSH-ir fibers were located mainly in the telencephalon, hypothalamus, and midbrain. -MSH-ir neuronal somata did not project their axons to the pituitary. The -MSH-ir neurons differed from those immunoreactive to melanin-concentrating hormone. -MSH cells in the pituitary and -MSH-ir neuronal somata in the brain were first detected 1 day and 5 days after hatching, respectively. The distribution of -MSH-ir cells, neuronal somata, and fibers showed a pattern similar to that in adult fish 30 days after hatching. These results indicate that the functions of -MSH in the brain and pituitary are different and that -MSH plays physiological roles in the early development of the barfin flounder. This study was supported in part by grants from the Regional Science Promotion Program Evolutional Research of the Japan Science and Technology Corporation, and the Yumekendo-Iwate Research and Promotion Project of the Iwate Prefectural Government Science and Technology Division to A.T.     

Theoretical prediction of antigenic sites in the Β-subunits of human choriogonadotropin and luteinizing hormone

Using hydrophilicity and recognition values of amino acids, the antigenic sites of theΒ-subunits of human choriogonadotropin and luteinizing hormone were computed from their amino acid sequences. Six antigenic sites were calculated for human choriogonadotropinΒ-subunits: residues 3–8, 17–22, 59–65,100–106,110–116 and 134–139. For luteinizing hormoneΒ-chain three antigenic sites were calculated: residues 17–22,59–65, and 100–106; all these three sites of luteinizing hormoneΒ being identical to the corresponding sites in human choriogonadotropinΒ. There was no antigenic site in luteinizing hormone that was also not found in human choriogonadotropin. On the other hand, there were unique determinants in human choriogonadotropin that were not found in luteinizing hormone; these determinants were residues 3–8, 110–116 and 134–139     

Expression pattern of anti-Müllerian hormone (amh) in the hybrid fish complex of Squalius alburnoides

In fish of the Squalius alburnoides complex, hybridisation and polyploidy have affected sex ratios, resulting in strong correlations between sex and genotype. The preponderance of females among triploids and the occurrence of an all male lineage among diploids seem to imply that sex ratio deviations should have a strong genetic basis. Until now, no information has been gathered regarding the molecular basis of sex determination in this intricate hybrid system. Thus, putative regulatory elements of the cascade that potentially are involved in sex determination in S. alburnoides have to be investigated. Being reported to have an important role in teleost sex determination, and more particularly in male gonad development, the anti-Müllerian hormone, amh was a good initial candidate. Here we report the isolation, cloning and characterization of the amh ortholog in S. alburnoides and the ancestral species S. pyrenaicus. In adult S. alburnoides and S. pyrenaicus of both sexes, amh shows a gonad specific expression pattern, restricted to the Sertoli cell lineage in testis and to granulosa cells in ovaries. During development, it plays an early role in male gonad differentiation in S. alburnoides. Overall the observed patterns are similar to what has been reported in other teleost species. This suggests a conserved role of amh and implies that its expression dynamics cannot be directly responsible for the sex ratio deviations reported in S. alburnoides. It is possible that a conjunction of other factors could be contributing for sex ratio imbalance. The present results constitute the starting point in the characterization of the S. alburnoides sex determination cascade, a process that we expect to shed some light on the molecular basis of sex distribution, within the context of hybrid system evolution.     

An in vitro system for studying juvenile hormone induction of juvenile hormone esterase from the fat body of Trichoplusia ni (Hübner)

An in vitro fat body culture was used to study juvenile hormone esterase (JHE) regulation. The present study shows juvenile hormone can directly induce JHE activity to appear in the culture medium in a dose-dependent manner at physiological concentrations of JH. This induced appearance of JHE can be blocked with actinomycin D. Biochemical characterization of the in vitro produced JHE demonstrated that it had the same isoelectric points as that of the in vivo JHE activity. The JHE inhibitor 1-1-1 trifluoro-tetradecan-2-one gave the same inhibition profile and I₅₀ toward both in vivo and in vitro produced JHE activities. Finally, the JHE activity induced in vitro was immunologically similar to that occurring in vivo. The system should be useful for high resolution studies on the regulation of JHE.