The promise of growth hormone in sport: doped or duped

ABSTRACT Skeletal muscle is a target tissue of GH. Based on its anabolic properties, it is widely accepted that GH enhances muscle performance in sports. Athletic performance depends on muscle strength and the energy required to power muscle function. The energy required to power muscle function is derived from a continuum of anaerobic and aerobic sources. Molecular and functional studies provide evidence that in muscle GH stimulates the anaerobic and suppresses the aerobic energy system, in turn affecting power-based functional measures in a time-dependent manner. In recreational athletes, GH improves anaerobic capacity but has not been proven to significantly enhance muscle strength, power, or maximum rate of oxygen consumption. GH appears likely to selectively benefit sprint events and not physical performance that depends on strength and endurance. Arch Endocrinol Metab. 2019;63(6):576-81

Reported shoes size during GH therapy: is foot overgrowth a myth or reality?

Objectives To describe population reference values for shoes size, and to identify possible disproportional foot growth during GH therapy.Materials and methods Construction of percentile chart based on 3,651 controls (male: 1,838; female: 1,813). The GH treated group included 13 children with idiopathic short stature (ISS) and 50 children with normal height, but with height prediction below their target height; male: 26 and female: 37 mean ± SD age 13.3 ± 1.9 and 12.9 ± 1.5 years, respectively. GH (0.05 mg/kg/day) was used for 3.2 ± 1.6 years, ranging from 1.0-10.3 years. Height expressed as SDS, target height (TH) SDS, self-reported shoes size and target shoes size (TSS) SDS were recorded.Results Reference values were established showed as a foot SDS calculator available online at www.clinicalcaselearning.com/v2. Definitive shoes size was attained in controls at mean age of 13y in girls and 14y in boys (average values 37 and 40, respectively). In the study group, shoes size was -0.15 ± 0.9 and -0.02 ± 1.3 SDS, with target feet of 0.08 ± 0.8 and -0.27 ± 0.7 SDS in males and females, respectively. There was a significant positive correlation between shoes size and familial TSS, between shoes size and height and between TSS and TH. There was no correlation between duration of GH treatment and shoes size. Our data suggest that during long-term treatment with GH, patients maintain proportional growth in shoes size and height, and the expected correlation with the familial target.Conclusions We conclude that there is no excessive increase in the size of foot as estimated by the size of shoes in individuals under long term GH therapy.

Growth response of Egyptian children with idiopathic short stature during four years of growth hormone therapy.

BACKGROUND: Multiple factors affect the growth response to recombinant human growth hormone (rhGH) in children with idiopathic short stature (ISS). AIM: To evaluate the growth responses of children with ISS treated with rhGH, aiming to identify the predictors of growth response. MATERIALS AND METHODS: We studied 120 cases, 90 males (75%), with a mean age of 13.8±2.7 years and 30 females (25%), with a mean age of 12.3±2.5 years. All patients received rhGH with a standard dose of 20 IU/m2/week. The calculated dose per week was divided into six days and given subcutaneous at night. RESULTS: A significant positive trend was detected in the delta changes of all anthropometric data. For the first year, the growth response was positively correlated to CA and BA delay and negatively correlated to height, weight and IGF-1 SDSs. For the second year, the growth response was correlated positively to first year growth velocity, BA, triceps skin fold thickness SDS and deviation from target height, and negatively correlated to weight, IGFBP3 SDS and target height SDS. For the third year, the growth response was positively correlated to five variables namely target height, 2nd year growth velocity, IGF-1 SDS, weight SDS and triceps skin fold thickness SDS. For the fourth year, growth response was positively correlated to 2nd and 3rd year growth velocity, BA, deviation from target height and weight/ height SDS. CONCLUSION: Our study showed multiplicity of predictors that is responsible for response in ISS children treated with rhGH, and BA was an important predictor.

Response of the growth plate of uremic rats to human growth hormone and corticosteroids

Children with chronic renal failure in general present growth retardation that is aggravated by corticosteroids. We describe here the effects of methylprednisolone (MP) and recombinant human growth hormone (rhGH) on the growth plate (GP) of uremic rats. Uremia was induced by subtotal nephrectomy in 30-day-old rats, followed by 20 IU kg-1 day-1 rhGH (N = 7) or 3 mg kg-1 day-1 MP (N = 7) or 20 IU kg-1 day-1 rhGH + 3 mg kg-1 day-1 MP (N = 7) treatment for 10 days. Control rats with intact renal function were sham-operated and treated with 3 mg kg-1 day-1 MP (N = 7) or vehicle (N = 7). Uremic rats (N = 7) were used as untreated control animals. Structural alterations in the GP and the expression of anti-proliferating cell nuclear antigen (PCNA) and anti-insulin-like growth factor I (IGF-I) by epiphyseal chondrocytes were evaluated. Uremic MP rats displayed a reduction in the proliferative zone height (59.08 ± 4.54 vs 68.07 ± 7.5 æm, P < 0.05) and modifications in the microarchitecture of the GP. MP and uremia had an additive inhibitory effect on the proliferative activity of GP chondrocytes, lowering the expression of PCNA (19.48 ± 11.13 vs 68.64 ± 7.9 percent in control, P < 0.0005) and IGF-I (58.53 ± 0.96 vs 84.78 ± 2.93 percent in control, P < 0.0001), that was counteracted by rhGH. These findings suggest that in uremic rats rhGH therapy improves longitudinal growth by increasing IGF-I synthesis in the GP and by stimulating chondrocyte proliferation.

Combined Administration of Glutamine and Growth Hormone Synergistically Reduces Bacterial Translocation in Sepsis

We investigated the combined effect of glutamine (GLN) and growth hormone (GH) on bacterial translocation (BT) in sepsis. After single intraperitoneal injection of lipopolysaccharide (10 mg/kg), 48 rats were divided randomly into four groups of 12 animals each: the control group received chow orally; the GLN group received chow plus 10% GLN; GH group received chow plus GH; and the GLN/GH group received chow, 10% GLN, and GH. Twenty-four and 96 hr later, rats were sacrificed. Portal blood culture, bacterial colony counts of cultured mesenteric lymph nodes, mucosal thickness, malondialdehyde (MDA), and glutathione (GSH) levels in the gut mucosa were measured. There was no significant change of the rate of portal blood culture between all treatment groups at 24 and 96 hr. At 24 hr, the rats receiving combined treatment of GLN and GH showed lower bacterial colony counts and mucosal MDA levels than the control rats, and higher mucosal GSH levels than the control and GLN-treated rats. At 96 hr, rats treated with both GLN and GH exhibited lower bacterial colony counts and mucosal MDA levels, and higher mucosal thickness and GSH levels than control, GLN, or GH-treated rats. This study suggests that the combination of GLN and GH may synergistically reduce BT over time in sepsis.

Hormônio de crescimento na regeneração hepática em ratos / Growth hormone on liver regeneration in rats

Muitas substâncias têm sido utilizadas após hepatectomias parciais com o fim de se saber como elas atuam no processo de regeneração. Entre elas encontra-se o hormônio de crescimento. Visando conhecer a influência deste hormônio, 50 ratos Wistar, machos, com idade de 170 dias e peso médio de 380g, foram divididos em dois grupos de 25 animais, respectivamente experimento e controle. Sob anestesia inalatória de éter etílico sofreram laparotomia mediana e hepatectomia de aproximadamente 70 por cento, ressecando-se os lobos mediano e lateral esquerdo que eram pesados e em seguida fazia-se a laparorrafia. Os ratos do grupo experimento receberam hormônio de crescimento através de injeção diária, subcutânea, de 0,4U/kg num volume de 0,12ml. Os animais do controle receberam igual volume de água destilada pela mesma via. Sacrificados em lotes de cinco animais de cada grupo com 36, 72, 168, 240 e 336 horas. Avaliava-se o peso do animal e o peso total do fígado. Através da fórmula de Kwon et al. a regeneração hepática foi calculada. No estudo microscópico conhecia-se as figuras de mitose em campos. O percentual de regeneração do peso da víscera mostrou-se maior no grupo tratado com hormônio de crescimento nas aferições de 168h (p=0,011), 240h (p=0,011) e 336h (p<0,0001). Nos animais do grupo experimento a regeneração foi completa a partir de 168h enquanto que no controle não atingira 100 por cento com 336h. As figuras de mitose estiveram presentes no grupo experimento até 240h sendo significativamente maior no grupo experimento nas aferições de 36h (p<0,001) e 72h (p<0,01). Concluiu-se que o hormônio de crescimento leva à regeneração mais rápida do fígado após hepatectomia, em ratos

Prediccion de la estatura final en niñas con sindrome de turner tratadas con hormona de crecimento / Prediction of final height in girls with Turner syndrome treated with growth hormone

El tratamiento con hormona de crecimiento (GH) en niñas con síndrome de Turner (ST) mejoraría la velocidad de crecimiento (VC) y la predicción de estatura final (EF). Se estudiaron 21 niñas con ST tratadas con GH durante 1 (n=21), (n=18) y 3 años (n=10). La edad cronológica media de inicio del tratamiento fue 11.6 +/- 2.6 años y la edad ósea media 9.7 +/- 2.4 años. El promedio de SDS de talla fue: -0.04 +/- 1.0 al inicio, 0.4 +/- 1.0 al año, 0.9 +/- 1.1 a los 2 años y 1.25 +/- 0.56 a los 3 años de tratamiento (p=0.0001, p < 0.001 y p < 0.05 respectivamente). El promedio de SDS de VC fue 1.6 +/- 1.8 al inicio, 2.5 +/- 1.7 al año, 3.8 +/- 2.9 a los 2 años y 2.2 +/- 2.0 a los 3 años (p=0.01, p=0.04 y p = 0.29 respectivamente). La predicación de EF por el método de Bayley-Pinneau fue: 142.8 cm +/- 5.2 a inicio, 143.8 +/- 6.0 al año, 146.0 +/- 5.9 a los 2 años y 145.6 +/- 6.4 a los 3 años de tratamiento (p= 0.026, p = 0.05 y p = 0.87 respectivamente). La estatura de alta promedio (EA) en 8 paciente fue 145.1 cm +/- 6.7. Conclusiones: 1) Se observó un retraso sistemático de edad ósea al iniciar el tratamiento con GH. 2) Se evidenció incremento de la VC y mejoría en las estaturas relativas y en la predicción de EF.3) La EA próxima a la predicción efectuada a los tres años de tratamiento, fue 7.2 cm mayor que la FE promedio de las niñas argentinas con EST no tratadas con GH.

Suplementação de hormônio do crescimento e zinco em pacientes com câncer de esôfago / Growth hormone and zinc supplementation in patients with esophageal cancer

Estudos preliminares com hormônio do crescimento (GH), como adjuvante nutricional em pacientes desnutridos com câncer tem demonstrado benefícios potenciais ao lado de resultados controversos. O zinco é um micronutriente relacionado à síntese protéica e à resposta hepática de IGF-1. Contudo, ainda não se tentou associar doses farmacológicas de zinco e GH em indivíduos levemente desnutridos. Tendo como objetivo avaliar o interesse clínico dessa associação em pacientes com câncer de esôfago, em fase pré-operatória, foi efetuado um estudo prospectivo com 47 pacientes. Os pacientes foram aleatorizados em quatro grupos de estudo: grupo I: placebo (grupo placebo); grupo II: placebo e zinco (50 mg de zinco elementar por via oral ou enteral ou 15 mg de zinco elementar junto com nutrição parenteral - grupo Zn); grupo III: 16 UI de GH/dia (grupo GH) e grupo IV: mesma dose de GH em combinação com a mesma dose de zinco (grupo GHZn)...

Body composition and bone mass of children with hypopituitarism following six months of human growth hormone therapy

Total body composition and the bone mineral content (BMC) and density (BMD) of 8 perpubertal (4 boys and 4 girls) GH-deficient children aged 6-14 years were investigated before and during a 3-6 month period on human growth hormone (hGH) therapy (0.075 IU/Kg/day, sc.); measurements were made by dual energy x-ray absorptiometry (DEXA). Before hGH therapy, total body fat mass was 4 + 3 kg and the total body percentage of fat was 22 + 12 per cent; the total lean mass was 14 + 3 kg. Total BMC was 625 + 163 g, and total BMD was 0.777 + 0.025 g/cm2. When compared with a matched population of normal children, GH-deficient children presented decreased lean mass (-0.9 to -5.9 SD), BMC (-0.9 to - 5.6 SD) and BMD (-0.1 to -4 SD). Fat mass, as a percentage, was not significantly different between populations (22 + 12 per cent in GH-deficient children vs. 17 + 5 per cent in normal children, p>0.05). Therapy with hGH was associated with: (I) a major decrease of total body percentage of fat mass: -31 + 15 per cent after 6 months (p<0.05); and with (II) an increase in the total lean mass and total BMC, 14 + 8 per cent and 7 + 5 per cent, respectively (both p<0.05). Total BMD was not significantly changed after 6 months of hGH therapy. We conclude that hGH replacement therapy results in a major and rapid decrease of total fat mass and in a less pronoucend increase of total lean mass.

Síndrome de Turner: tratamento da baixa estatura com hormônio de crescimento / Turner's syndrome: treatment of the low body height with growth hormone

A baixa estatura (BE) é uma das principais queixas entre as meninas portadoras da Síndrome de Turner (ST). A disponibilidade de hormônio de crescimento sintético (hGH) na década de 80 possibilitou seu emprego como o intuito de melhorar a altura final em várias doenças e síndromes, incluindo a ST. Algumas publicaçoes sugerem que o uso de hGH em portadoras da ST aumentaria a altura final destas meninas. O objetivo deste estudo é apresentar a evoluçäo da altura de crianças e adolescentes portadoras da ST ao final de dois anos de tratamento com hGH. Foram estudadas 28 portadoras da ST, distribuídas em três grupos: o grupo 1 constituído por sete crianças com até 10 anos de idade cronológica (IC), o grupo 2 formado por sete adolescentes, ou seja, a partir dos 10 anos de IC e um terceiro grupo tido como referência com 14 portadoras da ST que nunca foram tratadas com hGH e já atingiram sua altura final de 138,7+6,6. Os resultados, após o segundo ano de tratamento, dao como projeçäo de altura final para o grupo 1 valores iguais a 160,2+3,3 e para o grupo 2 de 146,5+7,3. A projeçäo de altura do grupo 1 foi significativamente maior do que o grupo näo tratado (p=0,045), o mesmo näo ocorrendo com o grupo 2. A velocidade de crescimento durante o tratamento aumentou, quando comparado à velocidade de crescimento do ano anterior ao tratamento para os dois grupos ao final do primeiro ano de hGH, e apenas para o grupo 1, após o segundo ano de tratamento. A velocidade de crescimento, do grupo 2, no segundo ano de tratamento näo foi estatisticamente diferente do ano anterior ao hGH. Os dados apresentados evidenciam bons resultados em crianças com menos de 10 anos de IC, o mesmo näo ocorrendo nas adolescentes.