Effect of growth hormone (GH) and resistance training on the collagen properties of femoral bone tissue / Efecto de la hormona de crecimiento (HC) y el entrenamiento de fuerza en las propiedades colágenas del tejido óseo femoral

The indiscriminate use of anabolic steroids in gyms has been growing in a generalized way, among which, the most common is growth hormone (GH). In the short term GH may potentiate muscle growth, especially when taken in combination with resistance training. However, the effects of this hormone are not yet fully understood in the literature, especially in relation to collagen properties. The objective of this study was to evaluate the effect of the application of growth hormone (GH) and resistance training (RT) on the collagen properties of femoral bone tissue using Raman Spectroscopy. In this study 40 male rats were randomly distributed into four groups (n=10): control (C), control and GH application (GH), resistance training (T), and resistance training and GH application (GHT). The training consisted of four series of 10 water jumps, performed three times a week, with an overload corresponding to 50 % of body weight and duration of four weeks. GH was applied at a dosage of 0.2 IU/Kg (0.067 mg/kg) to each animal, three times a week, every other day. The animals were euthanized and the right femurs were collected for analysis of bone structure. Raman spectroscopy (RS) was used to observe the following compounds from their respective bands: type I collagen (662 cm-1), amide III (1243 cm-1), proteins including type I collagen (1278 cm-1), woven collagen (1322 cm-1), association of collagen, phospholipids, nucleic acid, and phosphate (1330 cm-1), and collagen and protein deformation (1448 cm-1). The results demonstrated an increase in the collagen properties in all analyzed variables, however, the T group presented a statistically significant difference (p<0.05). It is possible to conclude that isolated physical training was shown to be more efficient than when combined with the application of GH to increase the collagen properties of the femoral bone tissue.

El uso indiscriminado de anabolizantes en los gimnasios ha aumentado de forma generalizada, entre éstos la hormona de crecimiento (HC) es una de las más utilizadas, y a corto plazo puede potencializar el crecimiento muscular, principalmente cuando es realizado en combinación con el entrenamiento de fuerza. Sin embargo, los efectos de esta hormona aún no están totalmente esclarecidos en la literatura, especialmente en relación a las propiedades colágenas. El objetivo del estudio fue evaluar el efecto de la aplicación del HC y entrenamiento de fuerza (E) en las propiedades colágenas del tejido óseo femoral a partir de la utilización de la espectroscopía Raman. Se usaron 40 ratas Wistar distribuidos en cuatro grupos (n=10): control (C), control y aplicación del HC (HCC), entrenamiento de fuerza (E) y entrenamiento de fuerza y aplicación del HC (THC). El entrenamiento fue compuesto por cuatro series de 10 saltos acuáticos, realizados tres veces por semana, con sobrecarga correspondiente a 50 % del peso corporal y duración de cuatro semanas. El HC fue aplicado en una dosificación de 0,2 UI/Kg (0,067 mg/kg) en cada animal, tres veces por semana, en días no consecutivos. Los animales fueran eutanasiados y se retiró el fémur derecho para realización del análisis de la estructura ósea. La espectroscopía Raman (ER) fue utilizada para observar los siguientes compuestos a partir de las respectivas bandas: colágeno tipo I (662 cm-1), amida III (1243 cm1), proteínas, incluido colágeno tipo I (1278 cm-1), colágeno retorcido (1322 cm-1), asociación de colágeno, fosfolípidos, ácidos nucleicos y fosfato (1330 cm-1), deformación de colágeno y proteína (1448 cm-1). Hubo aumento en las propiedades colágenas en todas las variables analizadas, sin embargo, solamente el grupo E demostró una diferencia estadísticamente significativa (p<0,05). En conclusión, para el aumento de las propiedades colágenas del tejido óseo femoral, el entrenamiento físico aislado es más eficiente que el entrenamiento combinado con el uso de HC.

Effect of intra-hippocampal injection of human recombinant growth hormone on synaptic plasticity in the nucleus basalis magnocellularis-lesioned aged rats / Efeito da injeção intrahipocampal de hormônio do crescimento humano recombinante sobre a plasticidade sináptica em ratos envelhecidos lesados do núcleo basalis magnocellularis

ABSTRACT In this study, we proposed that administration of hippocampal growth hormone in ageing animals with growth hormone deficiency can compensate long-term potentiation and synaptic plasticity in nucleus basalis magnocellularis (NBM)-lesioned rats. Aged male Wistar rats were randomly divided into six groups (seven in each) of sham-operated healthy rats (Cont); NBM-lesioned rats (L); NBM-lesioned rats and intrahippocampal injection of growth hormone vehicle (L + Veh); NBM-lesioned and intrahippocampal injection of growth hormone (10, 20 and 40 µg.2 µl-1) (L + GH). In vivo electrophysiological recording techniques were used to characterize maintenance of long-term potentiation at distinct times (1, 2, 3, 24 and 48 hours) after high-frequency stimulation. The population spike was enhanced significantly for about 48 hours following tetanic stimulation in rats treated with a dose-dependent growth hormone compared to the vehicle group (p < 0.05), possibly through neuronal plasticity and neurogenesis in affected areas.

RESUMO Neste estudo, propusemos que a administração de hormônio hipocampal do crescimento em animais envelhecidos com deficiência de hormônio do crescimento pode compensar a potencialização em longo prazo e a plasticidade sináptica em ratos lesados do núcleo basalis magnocellularis (NBM). Ratos machos Wistar foram divididos aleatoriamente em seis grupos (sete ratos em cada grupo) de ratos falso-operados saudáveis (Cont); ratos lesados do NBM (L); ratos lesados do NBM e injeção intrahipocampal de veículo de hormônio do crescimento (L + Veh); ratos lesados do NBM e injeção de hormônio do crescimento (10, 20 e 40 μg.2 μl-1) (L + GH). Técnicas de registro eletrofisiológico in vivo foram utilizadas para caracterizar a manutenção da potencialização em longo prazo em momentos distintos (1, 2, 3, 24 e 48 horas) após estimulação de alta frequência. O pico populacional aumentou significativamente cerca de 48 horas após a estimulação tetânica em ratos tratados com um hormônio do crescimento dose-dependente, em comparação com o grupo veículo (p <0,05), possivelmente através da plasticidade neuronal e da neogênese nas áreas afetadas.

Effects of Growth Hormone on Cardiac Remodeling During Resistance Training in Rats / Efeitos do Hormônio do Crescimento na Remodelação Cardíaca Durante Treinamento Resistido em Ratos

Abstract Background: Although the beneficial effects of resistance training (RT) on the cardiovascular system are well established, few studies have investigated the effects of the chronic growth hormone (GH) administration on cardiac remodeling during an RT program. Objective: To evaluate the effects of GH on the morphological features of cardiac remodeling and Ca2+ transport gene expression in rats submitted to RT. Methods: Male Wistar rats were divided into 4 groups (n = 7 per group): control (CT), GH, RT and RT with GH (RTGH). The dose of GH was 0.2 IU/kg every other day for 30 days. The RT model used was the vertical jump in water (4 sets of 10 jumps, 3 bouts/wk) for 30 consecutive days. After the experimental period, the following variables were analyzed: final body weight (FBW), left ventricular weight (LVW), LVW/FBW ratio, cardiomyocyte cross-sectional area (CSA), collagen fraction, creatine kinase muscle-brain fraction (CK-MB) and gene expressions of SERCA2a, phospholamban (PLB) and ryanodine (RyR). Results: There was no significant (p > 0.05) difference among groups for FBW, LVW, LVW/FBW ratio, cardiomyocyte CSA, and SERCA2a, PLB and RyR gene expressions. The RT group showed a significant (p < 0.05) increase in collagen fraction compared to the other groups. Additionally, the trained groups (RT and RTGH) had greater CK-MB levels compared to the untrained groups (CT and GH). Conclusion: GH may attenuate the negative effects of RT on cardiac remodeling by counteracting the increased collagen synthesis, without affecting the gene expression that regulates cardiac Ca2+ transport.

Resumo Fundamento: Apesar de os efeitos benéficos do treinamento resistido (TR) sobre o sistema cardiovascular estarem bem estabelecidos, poucos estudos têm investigado os efeitos crônicos da administração de hormônio do crescimento (GH) sobre a remodelação cardíaca durante um programa de TR. Objetivo: avaliar os efeitos do GH sobre a remodelação cardíaca em suas características morfológicas e na expressão dos genes do trânsito de Ca2+ em ratos submetidos ao TR. Métodos: Ratos Wistar machos foram divididos em 4 grupos (n = 7 por grupo): controle (CT), GH, TR e TR com GH (TRGH). A dose de GH foi de 0,2 UI/kg, a cada dois dias, por 30 dias. O modelo de TR utilizado foi o salto vertical em água (4 séries de 10 saltos, 3 vezes/semana) durante 30 dias consecutivos. Após o período experimental, as seguintes variáveis foram analisadas: peso corporal final (PCF), peso do ventrículo esquerdo (PVE), razão PVE/PCF, área seccional de cardiomiócitos (ASC), fração de colágeno, creatina quinase fração músculo-cérebro (CK-MB) e expressão gênica de SERCA2a, fosfolambam (PLB) e rianodina (RyR). Resultados: Não houve diferença significativa (p > 0,05) entre os grupos para PCF, PVE, razão PVE/PCF, ASC, e expressão gênica de SERCA2a, PLB e RyR. O grupo TR mostrou um significativo aumento (p < 0,05) da fração de colágeno em comparação aos outros. Além disso, os grupos treinados (TR e TRGH) apresentaram maiores níveis de CK-MB em comparação aos não treinados (CT e GH). Conclusão: Esses resultados indicam que o GH pode atenuar os efeitos negativos do TR na remodelação cardíaca por contrabalançar o aumento da síntese de colágeno, sem afetar a expressão de genes que regulam o trânsito de Ca2+ cardíaco.

Growth hormone in the presence of laminin modulates interaction of human thymic epithelial cells and thymocytes in vitro

BACKGROUND: Several evidences indicate that hormones and neuropeptides function as immunomodulators. Among these, growth hormone (GH) is known to act on the thymic microenvironment, supporting its role in thymocyte differentiation. The aim of this study was to evaluate the effect of GH on human thymocytes and thymic epithelial cells (TEC) in the presence of laminin. RESULTS: GH increased thymocyte adhesion on BSA-coated and further on laminin-coated surfaces. The number of migrating cells in laminin-coated membrane was higher in GH-treated thymocyte group. In both results, VLA-6 expression on thymocytes was constant. Also, treatment with GH enhanced laminin production by TEC after 24 h in culture. However, VLA-6 integrin expression on TEC remained unchanged. Finally, TEC/thymocyte co-culture model demonstrated that GH elevated absolute number of double-negative (CD4-CD8-) and single-positive CD4+ and CD8+ thymocytes. A decrease in cell number was noted in double-positive (CD4+CD8+) thymocytes. CONCLUSIONS: The results of this study demonstrate that GH is capable of enhancing the migratory capacity of human thymocytes in the presence of laminin and promotes modulation of thymocyte subsets after co-culture with TEC.

Fatores ambientais associados ao tempo de decisão para procura de atendimento no infarto do miocárdio / Environmental factors associated with the decision time for seeking care in myocardial infarction / Factores ambientales asociados con el tiempo de decisión para la búsqueda de atención en el infarto de miocardio

Objetivou-se estimar o tempo de decisão para procura de atendimento (TD) para homens e mulheres com infarto agudo do miocárdio (IAM); analisar a influência de variáveis ambientais no TD e a interação entre gênero e variáveis ambientais para o desfecho TD. Estudo transversal, envolvendo cem pacientes, entrevistados em hospitais de Salvador. Na análise dos dados empregou-se o Qui-quadrado ou Exato de Fisher e o Modelo de Regressão Linear Robusto. Predominou o IAM ocorrido no domicílio, familiares no entorno, e os pacientes sendo alvo de ações equivocadas. Observou-se TD elevado para mulheres (0,9h) e homens (1,4h). Aqueles em casa no início dos sintomas tiveram maior TD, comparados aos no trabalho e menor em relação aos em via pública (p=0,047). Houve interação estatisticamente significante entre gênero e viver acompanhado; e entre gênero e ter companheiro e filhos no entorno, para o desfecho TD. O cuidar em enfermagem focalizado nas especificidades de fatores ambientais e de gênero pode otimizar o atendimento precoce.

The purpose was to estimate the decision time (DT) for searching for attendance for men and women suffering from acute myocardial infarction (AMI); and to analyze the influence of surrounding variables in the DT. Transversal study, involving one hundred patients interviewed in hospitals of Salvador-BA, Brazil. For data analysis, it was used the chi-squared or Fisher’s exact test, and the Robust Linear Regression Model. AMI at the home predominated, with family members and patients receiving mistaken actions. A high DT was observed both, for women (0.9h) and men (1.4h). Those at home during the initial symptoms had higher DT, compared to those at work; and lower in relation to those in public spaces (p=0.047). Statistically significant interaction occurred among gender and the fact of living with company; and among gender and having a companion and children, for the outcome of the DT. Nursing care focused on the specificity of surrounding factors and gender can optimize early attendance.

Se objetivó estimar el tiempo de decisión para buscar atendimiento (TD) para hombres y mujeres con infarto agudo de miocardio (IAM); analizar la influencia de variables ambientales en TD y la interacción entre genero y variables ambientales para el desfecho del TD. Estudio transversal, envolviendo cien pacientes entrevistados en hospitales de Salvador-BA, Brasil. En el análisis se utilizó el chi-cuadrado o el Teste Exacto de Fisher y el Modelo de Regresión Linear Robusto. Predominó el IAM en el domicilio, familiares en el entorno y con pacientes siendo objeto de acciones equivocadas. Se observó TD elevados para mujeres (0,9h) y hombres (1,4h). Aquellos en sus casas en el inicio de los síntomas tuvieron mayor TD, comparados a los en el trabajo, y menor en relación aquellos en vía pública (p=0,047). Hubo interacción estadísticamente significante entre genero y vivir acompañado y entre genero y tener compañero e hijos en el entorno, para el desfecho del TD. El cuidar en enfermería focalizado en especificidades de factores ambientales y de géneros puede optimizar el atendimiento precoce.

Effect of Growth Hormone in Experimental Tooth Movement

The aim of this study was to evaluate, by histological analysis, the effect of growth hormone (GH) on periodontal ligament and alveolar bone during experimental tooth movement in rats. Eighty male Wistar rats divided into control (C) and experimental (E) groups were examined after 3, 7, 14 and 21 days under controlled climate conditions. Orthodontic force (30 cN) was applied on the maxillary first molar by an orthodontic appliance. Group E received 0.1 IU/kg/day of GH and Group C received 0.5 mL/kg/day of saline. The samples were processed and evaluated under optical microscopy and polarized light microscopy. The Kruskal Wallis test was applied to compare the intergroup variables at 5% significance level. Group E presented a larger number of osteoclasts on the 3rd and 7th days and Howship lacunae on the 3 rd day, a smaller number of blood vessels and greater amount of mature collagen on the 3 rd and 7 th days than Group C (p<0.05). It was concluded that GH accelerated and intensified bone resorption and produced delay in immature collagen formation during experimental tooth movement.

O objetivo deste estudo foi avaliar histologicamente o efeito do hormônio de crescimento (HC) no ligamento periodontal e osso alveolar, durante a movimentação dentária induzida em ratos. Oitenta ratos Wistar, machos, divididos nos grupos controle e experimental, foram observados nos dias 3, 7, 14 e 21. Foi aplicada força ortodôntica (30 cN) sobre o primeiro molar superior por meio de um dispositivo ortodôntico. No grupo experimental foi administrada 0,1 UI/kg/dia de HC e, no grupo controle, 0,5 mL/kg/dia de solução salina. As amostras foram processadas e avaliadas por microscopia de luz e luz polarizada. O teste de Kruskal Wallis foi utilizado para a comparação das variáveis intergrupos. Verificou-se que o grupo experimental apresentou maior quantidade de osteoclastos nos 3° e 7° dias e de lacunas de Howship no 3° dia, menor quantidade de vasos sanguíneos e maior quantidade de colágeno maduro nos 3° e 7° dias do que no grupo controle (p<0,05). Concluiu-se que o HC acelerou e intensificou a reabsorção óssea e produziu atraso na formação de colágeno imaturo, durante o movimento ortodôntico induzido.

Interaction between growth differentiation factor 9, insulin-like growth factor I and growth hormone on the in vitro development and survival of goat preantral follicles

The objective of this study was to determine the effects of GDF-9, IGF-I, and GH alone or combined on preantral follicle survival, activation and development after 1 and 7 days of in vitro culture. Either fresh (non-cultured) or cultured ovarian tissue was processed for histological and fluorescence analysis. For all media tested, the percent of normal follicles was greater when compared to minimum essential medium supplemented (MEM+) alone, except when ovarian tissue was cultured with GDF-9/IGF-I or GDF-9/GH (P < 0.05). Fluorescence analysis showed that the percent of viable follicles after 7 days of culture was similar for non-cultured tissue and for all treatments tested. The percent of primordial follicles was reduced (P < 0.05) and there was a significant and concomitant increase in the percent of intermediate and primary follicles in all treatments tested after 7 days of culture when compared to non-cultured tissue. After 7 days of culture, the highest percent of intermediate follicles was observed with IGF-I/GH (61.3 percent), and the highest percent of primary follicles was achieved with IGF-I (57.7 percent). After 7 days of culture in MEM+ containing GDF-9, IGF-I and GH alone or in all associations, a significant increase in follicular diameter was observed when compared to MEM+ alone and non-cultured tissue. In conclusion, GDF-9, IGF-I and GH alone or in combination maintain preantral follicle survival and promote primordial follicle activation. Nevertheless, the data showed that IGF-I/GH and IGF-I alone are efficient in promoting the transition from primordial to intermediate follicles and from intermediate to primary follicles, respectively.

Effect of calcium soaps of fatty acids and recombinant bovine somatotropin on productive and reproductive performance of baladi goats during early lactation

This study examined the mechanism by which calcium soaps of long chain of fatty acids [CSFA] and recombinant bovine Somatotropin [rbST] affect production and reproduction of Baladi goats [does]. The present study was carried out on 16 multiparous pregnant Baladi does aged 2.5 - 3 years. The treatments were initiated approximately four weeks before lambing until eight weeks post-lambing. Animals received 1 kg /head/day basal diet and allocated into four groups [n = 4 does /group]: without any treatment [control group I], plus 50 gm/head/day of CSFA [group II], 1 mg /kg body weight of rbST S/C injection every 14 days [group III], or a combination of CSFA supplementation and rbST injection [group IV]. It was found that a significantly shorter mean intervals [days] from lambing to first luteal activity and to conception and a higher percentage of ovarian cyclicity [100%] in group II and IV than in group I and III [75%]. Conception rate was also higher in group II and IV [100%] than group III [75%] and I [50%]. All kids of the treated groups had a significantly increase in their birth and weaning weights when compared with those from control group. There were significant increases in serum insulin in group II and IV and in serum leptin in all treated groups throughout the trial. Prolactin concentration was significantly higher in all treated groups than in the control one especially in rbST injected does. Also serum progesterone level showed a significant increase in all treated groups. Meanwhile, there was a significant effect of CSFA and rbST on T3 level during the first two weeks only of post-partum period and on T4 at day of lambing and during the second month of post-partum period. There was a significant increase in milk fat in all treated groups than control one, but showed highly significant increase in groups II and IV than in group III. Meanwhile, there was a non-significant effect of treatments on percentage of milk protein, total solids or solid not fat throughout the trial. In addition, there was a significant decrease in milk urea content in the three treated groups than in the control group. In conclusion, using of CSFA and rbST have a positive effect on lamb performance and milk composition. Meanwhile, CSFA supplementation has a more positive effect on reproductive performance, lamb performance and milk composition than injection of rbST. So, we recommend that using CSFA for does during late pregnancy and early post-partum period as a feed supplement at a level of 50 gm/head/day to improve reproductive performance, enhance metabolic profile, enhance lamb performance [in terms of birth weight, weaning weight and growth rate] and improve milk quantity and quality

Estimates of correlations among yield traits and somatic cell score with different models to adjust for bovine somatotropin effects on Holstein dairy cows

Records of Holstein cows from the Dairy Records Processing Center at Raleigh, NC were edited to obtain three data sets: 65,720 first, 50,694 second, and 65,445 later lactations. Correlations among yield traits and somatic cell score were estimated with three different models: 1) bovine somatotropin (bST) administration ignored, 2) bST administration as a fixed effect and 3) administration of bST as part of the contemporary group (herd-year-month-bST). Heritability estimates ranged from 0.13 to 0.17 for milk, 0.12 to 0.20 for fat, 0.14 to 0.16 for protein yields, and 0.08 to 0.09 for somatic cell score. Estimates were less for later than first lactations. Estimates of genetic correlations among yields ranged from 0.35 to 0.85 with no important differences between estimates with the 3 models. Estimates for lactation 2 agreed with estimates for lactation 1. Estimates of genetic correlations for later lactations were generally greater than for lactations 1 and 2 except between milk and protein yields. Estimates of genetic correlations between yields and somatic cell score were mostly negative or small (-0.45 to 0.11). Estimates of environmental correlations among yield traits were similar with all models (0.77 to 0.97). Estimates of environmental correlations between yields and somatic cell score were negative (-0.22 to -0.14). Estimates of phenotypic correlations among yield traits ranged from 0.70 to 0.95. Estimates of phenotypic correlations between yields and somatic cell score were small and negative. For all three data sets and all traits, no important differences in estimates of genetic parameters were found for the two models that adjusted for bST and the model that did not

Impact of bovine somatotropin on ranking for genetic value of dairy sires for milk yield traits and somatic cell score

Records of Holstein cows were used to examine how different models account for the effect of bovine somatotropin (bST) treatment on genetic evaluation of dairy sires for yield traits and somatic cell score. Data set 1 included 65,720 first-lactation records. Set 2 included 50,644 second-lactation records. Set 3 included 45,505 records for lactations three, four and five. Estimated breeding values (EBV) of sires were with three different animal models. With Model 1, bST administration was ignored. With Model 2, bST administration was used as a fixed effect. With Model 3, administration of bST was used to define the contemporary group (herd-year-month of calving-bST). Correlations for EBV of 1,366 sires with treated daughters between pairs of the three models were calculated for milk, fat and protein yields and somatic cell score for the three data sets. Correlations for EBV of sires between pairs of models for all traits ranged from 0.971 to 0.999. Fractions of sires with bST-treated progeny selected in common (top 10 to 15%) were 0.94 and usually greater for all pairs of models for all traits and parities. For this study, the method of statistical adjustment for bST treatment resulted in a negligible effect on genetic evaluations of sires when some daughters were treated with bST and suggests that selection of sires to produce the next generation of sires and cows might not be significantly affected by how the effect of bST is modeled for prediction of breeding values for milk, fat and protein yields and somatic cell score

Effect of growth hormone on fatty acid synthase gene expression in porcine adipose tissue cultures

We describe an efficient in vitro assay to test growth hormone effects on mRNA levels and fatty acid synthase (FAS, EC. 2.3.1.85) activity. Swine adipose tissue explants were long-term cultured in medium containing growth hormone and FAS mRNA levels and enzyme activity were measured. We quantified FAS transcripts by competitive reverse transcriptase PCR (RT-PCR) using total RNA from cultured adipose tissue explants and RT-PCR standard-curves were constructed using a cloned 307 bp segment of native FAS cDNA and a shorter fragment from which a 64 bp (competitor, 243 bp) internal sequence had been deleted. A known amount of competitor was added to each PCR as an internal control and æ-actin transcripts were also measured to correct for differences in total RNA extraction and reverse transcription efficiency. In cultures with added growth hormone FAS mRNA levels decreased 70 percent (p < 0.01) and FAS enzyme activity decreased 22 percent (p < 0.05). These in vitro growth hormone effects were consistent with those observed in vivo, showing that in vitro adipose tissue culture combined with RT-PCR is a useful and accurate tool for studying growth hormone modulation of adipose tissue metabolism. This technique allowed the diagnosis of lower levels of FAS mRNA in the presence of growth hormone and these low levels were associated with decreased FAS activity in the adipose tissue explants.

Effects of the combined use of glutamine and growth hormone in the intestinal adaptation after massive resection of the small bowel in rats

OBJETIVO: Investigar os efeitos do uso combinado da glutamina (GL) e do hormônio do crescimento (GH) no intestino de ratos submetidos a ressecção de 80% do intestino delgado. MÉTODOS: Vinte e quatro ratos Wistar foram randomizados para receber uma a dieta padrão- grupo controle (GC, n=12) ou a mesma dieta adicionada de glutamina 4% (isocalórica, isoproteica) - grupo glutamina- hormônio do crescimento (GL-GH, n=12) após a enterectomia à 80%. Este último grupo recebeu por via sub-cutânea, 0,6 UI/dia de GH. Grupos de seis ratos cada foram sacrificados no 5º e 14º dias. As seguintes variáveis foram estudadas: peso corporal, peso de mucosa, histomorfometria e conteúdo de DNA no segmento ressecado inicialmente e no intestino adaptado coletado após o sacrifício. RESULTADOS: Todos os animais perderam peso até o 5º dia, estabilizando-se após esta data em ambos os grupos. Não houve diferença estatística no peso da mucosa associada a grupos ou datas. O peso da mucosa do íleo diminuiu dos dados iniciais para os finais, quando comparados a mucosa jejunal (p<0.02). O conteúdo de DNA aumentou dos dados iniciais para os finais (p=0.001) em ambos os grupos, porém, o aumento foi maior nos animais do grupo GL-GH (CG = 0.53 [95% CI, 0.44-0.62] g/cm-1 vs. GL-GH= 0.85 [95%CI, 0.76-0.94] g/cm-1; p<0.01), especialmente no 14º dia. O conteúdo de DNA no íleo foi significativamente maior que no jejuno (p=0.01). Houve um aumento significativo na espessura da parede e na profundidade da cripta, no grupo controle (p<0.01). CONCLUSÃO: A adaptação intestinal após ressecção extensa é melhorada com o uso combinado de glutamina e GH.

Growth hormone mRNA expression in the pituitary of Bos indicus and Bos taurus x Bos indicus crossbred young bulls treated with recombinant bovine somatotropin

The effects of breed and of recombinant bovine somatotropin (rbST) treatment on growth hormone gene expression were studied in young bulls. The experiment was completely randomized in a [2 x 2]-factorial arrangement, using two levels of rbST (0 or 250 mg/animal/14 days), and two breed groups (Nelore and Simmental x Nelore crossbred). A cDNA encoding Bos indicus growth hormone was cloned and sequenced for use as a probe in Northern and dot blot analyses. Compared to the Bos taurus structural gene, the Bos indicus cDNA was found to begin 21 bases downstream from the transcription initiation site and had only two discrepancies (C to T at position 144-His and T to C at position 354-Phe), without changes in the polypeptide sequence. However, two amino acid substitutions were found for Bubalus spp., which belong to the same tribe. The rbST treatment did not change any of the characteristics evaluated (body and pituitary gland weights, growth hormone mRNA expression level). Crossbred animals had significantly higher body weight and heavier pituitaries than Nelore cattle. Pituitary weight was proportional to body weight in both breed groups. Growth hormone mRNA expression in the pituitary was similar (P>0.075) for both breed and hormonal treatment groups, but was 31.9 higher in the pure Nelore group, suggesting that growth hormone gene transcription regulation differs among these breeds

Neogénesis y regeneración de las células beta pancreáticas / Pancreatic beta-cell neogenesis and regeneration

OBJECTIVE: To review the literature on beta-cell neogenesis and regeneration, with special interest in substances that regulate such processes. DESIGN: Representative papers were selected through a computer MEDLINE search from 1990 to 2000. RESULTS: Several studies showed that once islets of Langerhans developed from small pancreatic ducts, this process did not continue in normal adult individuals. However, it has been published that new beta-cell formation can occur in vivo in certain experimental models through neogenesis, in which gene pax 4 is extremely important. On the other hand, substances that stimulate the regenerative process of beta-cells include glucose, several hormones and certain growth factors. CONCLUSIONS: Substances that stimulate the regenerative process commonly express this effect in elevated, non-physiologic concentrations; thus, their possible therapeutic importance is not yet clear. Nevertheless, the Reg protein, present in regenerative pancreas and implied in neogenesis process, has actual possibilities of becoming therapeutically important.

Effect of 12 months of recombinant human growth hormone replacement therapy on insulin sensitivity in GH-deficient adults as determined by different methods.

BACKGROUND: Controversial results have been obtained in measuring insulin sensitivity (S(I)) during recombinant human growth hormone (rhGH) treatment in adult growth hormone deficient (GH-deficient) patients. AIMS: The aim of our study was to estimate S(I) before and during treatment using three different methods for quantifying insulin sensitivity in GH-deficient adults treated with rhGH. SETTINGS AND DESIGN: Twenty-one GH-deficient adults were treated with rhGH during 12 months. S(I) was estimated using Minimal model analysis, Homeostatic Model of Assessment (HOMA) and Quantitative Insulin Sensitivity Check Index (QUICKI) before and after 3, 6, 9 and 12 months of rhGH therapy. MATERIAL AND METHODS: Oral Glucose Tolerance Test (OGTT) and Frequently Sampled Intravenous Glucose Tolerance Test (FSIGT) were performed in each patient at respective time intervals. QUICKI and HOMA were calculated using basal values of glucose and insulin from FSIGT. Minimal model computer analysis was calculated from glucose and insulin data obtained during FSIGT. STATISTICAL ANALYSIS: Area under the curve for glucose, insulin and C-peptide were calculated using trapezoidal rule from OGTT data. Differences and correlations were tested using ANOVA for repeated measures, Wilcoxon's matched-paired test, paired t-test, Pearson's correlation and Bland Altman plot. RESULTS: There were no significant changes in S(I) using Minimal model analysis and QUICKI during rhGH treatment. On the contrary, HOMA analysis indicated significant deterioration in S(I) after 12 months of therapy. CONCLUSION: Our study did not demonstrate any changes in S(I) using Minimal model and QUICKI analysis, while there was significant increase in insulin resistance using HOMA model. We suggest that the choice of method for the determination of S(I) may influence the interpretation of results concerning the effect of rhGH therapy on S(I) in GH-deficient adults.

The effect of growth hormone on the development of in vitro matured unstimulated human oocytes.

OBJECTIVE: To investigate the effect of growth hormone on the development of in vitro matured unstimulated human oocytes. DESIGN: Randomized controlled study. SETTING: Division of Reproductive Medicine, Department of Obstetrics and Gynecology, Faculty of Medicine, Chulalongkorn university. MATERIAL AND METHOD: 108 germinal vesicle-stage oocytes were retrieved from 47 patients undergoing gynecologic surgery. They were aspirated either during gynecologic surgery or from excised ovaries. The oocytes were then cultured in vitro with or without growth hormone (1,000 ng/ml) in medium199 supplemented with sodium pyruvate, FSH, LH, antibiotic and synthetic serum. Incubation was done at 37 degree C with 5 per cent CO2 in air and nuclear stage was assessed after 18, 42, 66 and 90 h of incubation. MAIN OUTCOME MEASURE: Attainment of metaphase II and GVBD RESULTS: After in vitro culture, there were no significant differences in maturation and GVBD rate. 27 of 52 (51.9%) oocytes (GV) in growth hormone group matured to metaphase II compared with 25 of 53 (47.2%) GV in control group. GVBD rate for germinal vesicle-stage in growth hormone group was 76.9 per cent compared with 79.2 per cent in control group. CONCLUSION: Culture of immature oocytes in vitro with growth hormone results in similar maturation rate as that without GH.

Effects of ovine LH, GH and prolactin, and testosterone on serum testosterone and estradiol-17 beta levels, and seminal vesicle and testicular activity in the catfish Clarias batrachus (L.).

Intraperitoneal administrations of testosterone (0.5 microgram/g body wt), and ovine LH (1.0 microgram/g body wt), GH (5 micrograms/g body wt) and prolactin (10 micrograms/g body wt) daily for 7 days during early prespawning phase (May) in C. batrachus produced varied effects on seminal vesicle (SVSI) and testicular (GSI) weights and biochemical correlates. Testosterone and LH treatments significantly increased serum testosterone level and concentrations of total proteins, fructose, hexosamines and sialic acid in both seminal vesicles and testis. Serum E2 levels increased significantly only after testosterone treatment. GH treatment increased significantly serum testosterone level and only the concentrations of SV hexosamines and testicular protein. Prolactin, however, significantly lowered serum testosterone level and concentrations of total protein, hexosamines in both SV and testis, and testicular fructose and sialic acid levels. The results show that the stimulating effect of LH and GH on SV and testicular activity is mediated through the increased secretion of testosterone and the inhibitory effect of prolactin by decreased testosterone secretion.

O hormônio de crescimento e a concentraçäo de colágeno na cicatrizaçäo de feridas cutâneas de ratos / Growth hormone and collagen concentration in the skin wounds healing of rats

Investiga-se a interferência do hormônio de crescimento no processo de cicatrização cutânea de ratos. Utilizaram-se 50 ratos machos com 170 dias de idade divididos em 2 grupos: controle (n=25) e experimento (n=25). Submeteram-se os ratos dos dois grupos à laparotomia mediana de 4 centímetros sob anestesia inalatória de éter etílico. Realizou-se a laparorrafia com 2 planos de sutura, o primeiro peritônio-músculo-aponevrótico e o segundo o da pele com chuleio contínuo de fio monofilamentar de náilon 4.0. Os animais do grupo experimento receberam 0,4U/kg/dia de hormônio de crescimento por via subcutânea diluído em 0,12 ml de água destilada e os do grupo controle recebiam igual volume do veículo pela mesma via. Realizaram-se as aferições após 36, 72, 168, 240 e 336 horas, ressecando-se retalhos da parede abdominal contendo as cicatrizes, que após preparação histológica e tratamento pelo Sirius red, forneceram a concentração do colágeno. O percentual da área de cicatriz ocupada por colágeno foi maior no grupo experimento nas 36 horas (p=0,0106), 72 horas (p=0,0089, 168 horas (p=0,0149) e 336 horas (p=0,0116). O percentual de colágeno I foi semelhante nos dois grupos nas 36 e 72 horas e maior no grupo experimento nas 168 horas (p=0,0218), 240 horas (p=0,0067) e nas 336 horas (p=0,0027). O percentual de colágeno III apareceu em proporção semelhante nos 2 grupos nas 36 e 72 horas. Sua proporção foi maior no grupo controle nas 168 horas (p=0,0216), 240 horas (p=0,0067) e 336 horas (p=0,0027). Estes dados permitiram concluir que o hormônio de crescimento levou a maior concentração de colágeno e acelerou a maturação das cicatrizes.

Efecto de la hormona somatotropica sobre la secrecion de insulina de perros cachorros / Effect of somatotropic hormone on insulin secretion in pups

En el presente estudio se abordó el efecto de la somatotropina de origen bovino (bSTH) en el perro cachorro. Se pbservó el perfil diario caracterizado por un incremento de la insulina inmunorreactiva sérica (IIR) a partir de las 6h de la administración subcutánea de bSTH, el cual se mantiene por 24h. La glicemia permaneció dentro de los límites normales observados en el periodo control, mientras que los ácidos grasos libres sufrieron un incremento significativo. La adminsitración intravenosa de glucosa, a las 24h de una segunda dosis de bSTH, prodyjo una excursión de la glucemia dentro de límites normales, con un exagerado aumento de la IIR, creando una situación que semeja los estados de resistencia insulínica. Los resultados señalan en el cachorro una respuesta cualitativamente similar a del perro adulto, en la cual la hiperinsulinemia debe jugar papel importante en el sostenimiento de la normoglicemia.