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OALib Journal期刊

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Growth Hormone Involvement in Growth, Oogenesis, Sex Determination and Differentiation in Russian Sturgeon (Acipenser gueldenstaedtii): An Integrative Review  [PDF]
Gad Degani
Voice of the Publisher (VP) , 2026, DOI: 10.4236/vp.2026.122023
Abstract: Growth hormone (GH) plays a pivotal integrative role in regulating growth, reproduction, sex determination, and differentiation in the Russian sturgeon (Acipenser gueldenstaedtii), a species of major economic importance for caviar production in aquaculture. This mini-review synthesizes current knowledge on the interaction between the somatotropic axis (GH-IGF-I) and the brain-pituitary-gonadal (BPG) axis, highlighting their coordinated involvement across developmental stages. During early life stages (larvae and juveniles), growth is primarily influenced by environmental factors, and no clear sexual dimorphism is observed. However, following gonadal differentiation, pronounced sex-related growth differences emerge, with females exhibiting enhanced somatic growth and lipid accumulation associated with oogenesis and vitellogenesis, while males allocate energy predominantly to spermatogenesis. The review describes the endocrine regulation of oocyte development, including pre-vitellogenic growth, estradiol-induced hepatic vitellogenin synthesis, and final oocyte maturation triggered by luteinizing hormone (LH) and maturation-inducing steroids (MIS). In parallel, spermatogenesis is regulated by gonadotropins (FSH and LH), androgens, and local testicular factors, with additional modulation by the GH-IGF-I system. Furthermore, artificial fertilization is presented as a key aquaculture tool, linking endocrine control mechanisms to practical applications in broodstock management, larval production, and genetic improvement programs. Special emphasis is placed on early sex determination strategies, which are essential for optimizing caviar production efficiency. Overall, this mini-review highlights GH as a central regulator connecting growth, reproductive physiology, and aquaculture performance, providing a comprehensive framework for improving production strategies in Russian sturgeon.
Testes de secre？？o de horm？nio de crescimento e suas implica？？es no tratamento da baixa estatura
Seick, Daniela;Boguszewski, Margaret C.S.;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2003, DOI: 10.1590/S0004-27302003000400003
Abstract: the use of gh provocative tests to diagnose children with short stature continues to be a controversial issue. gh secretion is considered a continuum ranging from absent to normal secretion. when gh deficiency is severe, as in gh gene defects and craniopharyngiomas, there is a very important growth failure and absent or minimal gh response to stimulation tests. these situations could be used as standards to define total gh deficiency. however, partial gh deficiency also can show growth failure, but with variability of gh secretion on provocative tests. moreover, several factors can influence gh secretion and gh-igf axis. determination of cutoff values in a non-physiological test to define normality is erroneous and can induce to error. moreover, the lack of knowledge of normal values for different tests and assays in each clinical situation increases the difficulty to decide the treatment of a child with short stature based only on the results of a gh provocative tests. the considerations above do not mean that gh provocative tests are not important for diagnosis of short stature, but that the results of these tests should not be the final determinant of a clinical decision. they should be used in association with the clinical picture and other laboratory methods available to evaluate the hypothalamo-pituitary region and the gh-igf axis. to reduce the risk of unnecessary treatment of a child with normal pituitary function and, on the other hand, to avoid delay or no-treatment of a child that could benefit with the use of recombinant human gh should be the principles to orient a medical decision.
Growth Hormone Secretagogues: Between Endocrine Physiology and the Therapeutic Frontier of GH-IGF-1 Axis-Modulating Peptides  [PDF]
Pedro Augusto Zaiats Junior, Pedro Senteio, Diego Ribeiro, Kerly Martendal
Open Journal of Clinical Diagnostics (OJCD) , 2026, DOI: 10.4236/ojcd.2026.163007
Abstract: Growth hormone (GH) plays a central role in the regulation of somatic growth, body composition, energy metabolism, bone homeostasis, and cardiovascular function. Physiological GH secretion is controlled by a complex interplay of hypothalamic factors, primarily growth hormone-releasing hormone (GHRH) and somatostatin, as well as ghrelin and several metabolic and hormonal modulators. Over the past decades, the development of growth hormone secretagogues (GHSs) has significantly expanded the possibilities for pharmacological modulation of the GH-insulin-like growth factor 1 (GH-IGF-1) axis. Growth hormone secretagogues comprise a heterogeneous class of compounds capable of stimulating endogenous GH secretion through activation of the growth hormone secretagogue receptor (GHS-R1a). This group includes synthetic peptides such as GHRP-2, GHRP-6, hexarelin, and ipamorelin, as well as non-peptide molecules such as ibutamoren (MK-677). More recently, novel peptide analogs and combination therapeutic strategies have been developed to optimize the somatotropic response while minimizing off-target effects on other endocrine pathways. This review summarizes the physiological mechanisms regulating the GH-IGF-1 axis, the pharmacological characteristics of the major growth hormone secretagogues currently available, their established and emerging clinical applications, and the current evidence regarding their efficacy and safety. In addition, it discusses future therapeutic perspectives, as well as the regulatory and ethical challenges associated with the use of these compounds in regenerative medicine, healthy aging, and physical performance enhancement.
Testes de secre o de horm nio de crescimento e suas implica es no tratamento da baixa estatura
Seick Daniela,Boguszewski Margaret C.S.
Arquivos Brasileiros de Endocrinologia & Metabologia , 2003,
Abstract: A valoriza o dos testes de secre o de GH no diagnóstico da baixa estatura continua sendo motivo de discuss es. A secre o de GH é considerada um continuum entre uma secre o normal e anormal. Situa es em que a deficiência de GH é severa, como nos defeitos do gene do GH e no craniofaringeoma, cursam com atraso importante do crescimento e ausência total ou quase total de GH nos testes provocativos. Estas situa es poderiam servir como padr o para definir a deficiência total de GH. Entretanto, a deficiência parcial ou menos severa de GH também cursa com atraso do crescimento, porém com um grau variável de resposta nos testes provocativos. Somando-se a isto, devemos considerar que muitos fatores est o envolvidos na secre o de GH e no eixo GH-IGFs. A determina o de valores de corte em um teste n o fisiológico que indique onde termina o normal e come a a deficiência é enganosa e pode induzir ao erro. Além disso, a falta de normatiza o dos diferentes testes e ensaios laboratoriais nas diferentes situa es clínicas aumenta a dificuldade para decidir sobre o tratamento de uma crian a com baixa estatura baseando-se apenas nos resultados dos testes provocativos. As considera es acima n o implicam que os testes de secre o de GH s o irrelevantes no diagnóstico da baixa estatura, mas que os resultados destes testes n o deveriam ser o determinante final de uma decis o clínica. Eles deveriam ser usados como medidas confirmatórias associadas ao quadro clínico e a todo o leque de exames atualmente disponíveis para avaliar a integridade da regi o hipotálamo-hipofisária e do eixo GH-IGFs. Reduzir o risco de prescrever um tratamento desnecessário para uma crian a com fun o hipofisária normal ao mesmo tempo em que evita-se o atraso ou o n o tratamento de uma crian a que poderia se beneficiar do uso do GH biossintético devem ser os princípios que norteiam a decis o do especialista.
Human conditions of insulin-like growth factor-I (IGF-I) deficiency
Puche Juan E,Castilla-Cortázar Inma
Journal of Translational Medicine , 2012, DOI: 10.1186/1479-5876-10-224
Abstract: Insulin-like growth factor I (IGF-I) is a polypeptide hormone produced mainly by the liver in response to the endocrine GH stimulus, but it is also secreted by multiple tissues for autocrine/paracrine purposes. IGF-I is partly responsible for systemic GH activities although it possesses a wide number of own properties (anabolic, antioxidant, anti-inflammatory and cytoprotective actions). IGF-I is a closely regulated hormone. Consequently, its logical therapeutical applications seems to be limited to restore physiological circulating levels in order to recover the clinical consequences of IGF-I deficiency, conditions where, despite continuous discrepancies, IGF-I treatment has never been related to oncogenesis. Currently the best characterized conditions of IGF-I deficiency are Laron Syndrome, in children; liver cirrhosis, in adults; aging including age-related-cardiovascular and neurological diseases; and more recently, intrauterine growth restriction. The aim of this review is to summarize the increasing list of roles of IGF-I, both in physiological and pathological conditions, underlying that its potential therapeutical options seem to be limited to those proven states of local or systemic IGF-I deficiency as a replacement treatment, rather than increasing its level upper the normal range.
Aspectos genéticos, influência do eixo GH/IGF1 e novas possibilidades terapêuticas na osteoporose idiopática
Lopes, Renata Francioni;Farias, Maria Lucia Fleiuss de;
Revista Brasileira de Reumatologia , 2006, DOI: 10.1590/S0482-50042006000200005
Abstract: idiopathic osteoporosis is a rare condition that affects both sexes, women during menacme and men before 65 years. the diagnosis can only be considered after all known causes of osteoporosis are discarded. the clinical presentation is heterogeneous, ranging from densitometric finding in a patient with few symptoms to multiple fragility fractures, mainly vertebral. bone turnover is usually in the low-normal range, but bone resorption always exceeds formation, resulting in net bone loss. the osteoblastic dysfunction, described in almost all papers, has been related to low insulin growth factor-1 (igf-1) concentrations in blood and bone matrix. genetic and hormonal factors seem to be involved. antiresorptive drugs, such as bisphosphonates, are useful in reducing fracture rate. anabolic drugs, such as growth hormone, igf-1 and more recently teriparatide (recombinant pth) are more promising, as they actually increase bone mass and improve bone quality. the purpose of this article is to review pathophysiologic aspects of idiopathic osteoporosis, diagnostic routine and therapeutic alternatives.
lnteracciones de la respuesta del eje somatotrófco en la amenorrea hipotalámica funcional relacionada con la desnutrición
Fiszlejder,L;
Revista argentina de endocrinolog？-a y metabolismo , 2011,
Abstract: the activity of the somatotropic function in functional hypothalamic amenorrhea (fha) is increased at the central level, and paradoxically, the peripheral hormonal behaviour, intermediate metabolism and several clinical aspects may be similar to those observed in somatotropic axis deficiency. baseline and daily gh secretion levels are high, but its pulsatile profile is irregular. this results in resistance to gh, i.e., downregulation of hormone receptors, which, together with the decrease in gh binding protein (ghbp), impair gh ability to stimulate the synthesis of igf-i, igfbp-3 and the acid-labile subunit in the liver. this causes a decrease in the availability of free igf-i in tissues. in addition, igfbp-1 and igf-bp2 significantly increase. even if these peptides are regulated by gh, their inverse correlation with insulin activity (which is decreased in these patients) and the low protein diet, respectively, appear to be more important factors. the increase in the serum levels of these peptides also contributes to the decrease in free igf-i. alterations in secretory patterns lead to a decrease in leptin concentration (an adipokine) and to an increase in ghrelin, which, in turn, facilitates gh secretion and has a remarkable incidence in intermediate metabolism in these undernourished patients. these hormonal changes can be interpreted as a mechanism of homeostatic adaptation tending to preserve availability of energetic nutrients. thus, there is an initial predominance of lypolisis followed by proteolysis at muscle level. if dietary restriction continues, a process of neoglucogenesis occurs in the liver and muscle tissue, with proteins and free fatty acids (nefas) being used as substrates. this is followed by glucogenolysis, which produces glucose. however, the increase in nefas and the potential presence of ketone bodies in highly restricted diets, suggest the presence of metabolic acidosis. this clinical condition implies an increased cardiovascular risk and th
lnteracciones de la respuesta del eje somatotrófco en la amenorrea hipotalámica funcional relacionada con la desnutrición The activity of the somatotrophic function in Functional Hypothalamic Amenorrhea (FHA) related to undernourishmant
L Fiszlejder
Revista Argentina de Endocrinología y Metabolismo , 2011,
Abstract: La función somatotrófica en la amenorrea hipotalámica funcional (AHF) exhibe un aumento central de su actividad y paradojalmente, el comportamiento hormonal periférico, el metabolismo intermedio y varios aspectos clínicos pueden ser compatibles con los observados en la insuficiencia del eje somatotrófico. Los niveles basales y la secreción diaria de GH son altas, pero su perfil pulsátil es irrregular. En virtud de ello, se produce una resistencia a la GH, con disminución de los receptores de la hormona, que, sumado al descenso de la proteína ligadora de GH (GH binding protein, GHBP), alteran su capacidad de estimular en el hígado las síntesis de IGF-I, IGFBP-3 y la de la subunidad acido-lábil. Ello disminuye la disponibilidad de IGF-I libre en los tejidos. Por otro lado, los IGFBP-1 y IGFBP-2 aumentan significativamente. Si bien estos péptidos son regulados por la GH, aparentemente resulta ser más importante su correlación inversa con la actividad de la insulina (que se encuentra disminuida en estas pacientes) y con el bajo aporte proteico de las dietas. El aumento de los niveles séricos de estos péptidos también contribuye al descenso de la IGF-I libre. Las alteraciones en la dinámica de secreción inducen a una reducción de la concentración de la leptina (una adipokina) y al aumento de la ghrelina (la cual, a su vez, facilita la secreción de GH) y presentan una destacada incidencia en el metabolismo intermedio de estas pacientes desnutridas. Estos cambios hormonales pueden ser interpretados como un mecanismo de adaptación homeostática tendiente a preservar la disponibilidad de los nutrientes energéticos. En relación a ello, existe inicialmente un predominio de la lipólisis, seguido de proteólisis a nivel muscular. Si la restricción dietética continúa, se desarrolla en el hígado y en el tejido muscular, un proceso de neoglu-cogénesis utilizando como sustrato, las proteínas y los NEFA. Ello es seguido por la glugenólisis que aporta glucosa. No obstante, el aumento de los ácidos grasos libres y eventualmente la aparición de cuerpos cetónicos cuando la alimentación es muy restringida, sugieren la presencia de acidosis metabólica. Este estadio clínico implica un aumento del riesgo cardiovascular y la posibilidad de muerte prematura o súbita, una eventualidad latente en las pacientes con AHF y desnutridas. El autor declara no poseer conflictos de intereses. The activity of the somatotropic function in Functional Hypothalamic Amenorrhea (FHA) is increased at the central level, and paradoxically, the peripheral hormonal behaviour, intermediate metabolism and se
Teste agudo com octreotide subcutaneo como preditor de resposta ao tratamento com octreotide LAR？
Taboada, Giselle F.;Donangelo, Ines;Guimar？es, Renata F.C.;Silva, Mariangélica de O.;Fontes, Rosita;Gadelha, M？nica R.;
Arquivos Brasileiros de Endocrinologia & Metabologia , 2005, DOI: 10.1590/S0004-27302005000300010
Abstract: somatostatin analogues are frequently used to treat acromegaly. to determine the value of the acute test (at) with subcutaneous (sc) octreotide as a predictor of the response to treatment with octreotide lar？, we analyzed data from 20 patients. for the at, blood was drawn before and two hours after the sc administration of octreotide for measuring gh. gh levels before and after the at were 21.9ng/ml (2.3-143.4) and 3.1ng/ml (0.3-61.3), respectively. control of the disease was defined as: gh< 2.5ng/ml and normal igf-i anytime during treatment. sensitivity, specificity, positive and negative predictive values of the at were 0.9, 0.6, 0.69 and 0.86 for a reduction of 75% of the gh on the test. from our sample we conclude that a 75% reduction of the gh levels during the acute test was able to discriminate patients with a higher or lower chance of responding to treatment.
Characterization of GH, GHR and IGF-I in Broiler Lines Selected for Rapid Growth or Improved Feed Efficiency
G. Rahimi
International Journal of Poultry Science , 2005,
Abstract: The aim of this study was to figure out the response of the GH axis to selection criteria in broiler chickens. Plasma profiles of GH, IGF-I along with membrane GHR binding activity were examined during rapid growth phase in experimental lines of broiler chickens. The selection criteria applied influenced the plasma GH levels and the number of hepatic GHR. There was a higher plasma GH level in FC chickens compared to GL chickens while the opposite pattern was observed for GHR. The negative correlation between plasma GH levels and hepatic GHR suggest a down regulatory mechanism for GHR in broiler chickens. The absence of line differences in plasma IGF-I levels between GL and FC lines in spite of clear difference in growth rate and in plasma GH concentrations may support the concept that plasma IGF-I does not appear to be GH-dependent, implying the importance of other factors besides GH in the regulation of IGF-I in chickens. The slower growth rate as function of time in the FC line during rapid growth phase was followed by a phase of compensatory growth. On the basis of this growth curve pattern it can be hypothesized that the dynamics of GH action are shifted or extended to the phase of compensatory growth as an effect of the selection on feed conversion. This may be a causal mechanism for the different growth curve pattern in GL and FC lines. Assuming that the metabolic basis for these differences is better understood it may be possible to device other procedures for improving meat quality in poultry industry.
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