The Effect of Gender and Age on Growth Hormone Replacement in Growth Hormone-Deficient Patients

Abstract

We analyzed the effect of growth hormone replacement therapy (36 months) analyzed at a dose adjusted to maintain serum insulin-like growth factor-I level between the median and the upper end of the age-related reference range on bone mineral density, body composition, and carbohydrate metabolism with respect to gender and age in 20 adult patients (9 women, 11 men, mean age: 43 years, range: 21-61 years). The lumbar and femoral T-score was increased after 12 and after 18 months of therapy respectively in men (p < 0.001 and p = 0.002), but did not changed significantly in women. The increase of femoral T-score was greater in young men (< or = 45 years, n = 6) than old men (> 45 years, n = 5, p < 0.001). Body fat was lower in men than in women after 6 months (p = 0.002). The waist/hip ratio only decreased in women (p = 0.044). The waist circumference decreased in both genders after 6 months of therapy (p < 0.001), but more markedly in females than in males (p < 0.05). The sum of skinfold thicknesses was reduced in males after 6 months of therapy (p < 0.001). Changes in body composition parameters measured were independent of age. The glycosylated hemoglobin increased without sex or age difference after 12 months of initiation of therapy (p < 0.001), but fasting glucose and insulin levels did not change during the therapy. Our results indicate that the effect of growth hormone replacement on bone mineral content in adults is age- and gender-dependent, gender dependent on body composition, but independent of age and gender on carbohydrate metabolism.

Permanent uncoupling of male-specific CYP2C11 transcription/translation by perinatal glutamate

“…The fundamental regulatory difference between male and female GH profiles in all species examined is the much longer GH-devoid interpulse period observed in adult males (Agrawal and Shapiro, 2001; Legraverend et al, 1992; Pampori and Shapiro, 1996; Waxman et al, 1991). In addition to sex differences in CYP expression, this masculine GH secretory signal is responsible, at least in part, for sex differences in growth rates, lean body mass; cardiovascular, bone, adipose, and muscle function; protein, carbohydrate, lipid and electrolyte metabolism (Bengtsson, 1999; Burman et al, 1997; Hubina et al, 2004; Jørgensen and Christiansen, 2005; Kuromaru et al, 1998; Span et al, 2001) and expression levels of hepatic insulin-like growth factor-1 (IGF-1), IGF binding protein and GH binding protein (Hubina et al, 2004; Jansson et al, 1985; Johansson, 1999; Johansson et al, 1999; Jørgensen and Christiansen, 2005; Soares et al, 2004). …”