Biomedical subjects

P Gillberg

Publications and source records attributed to P Gillberg.

5 recordsLinked to original sources

PubMed2002

Ambulatory morning growth hormone concentrations increase in men and decrease in women with age.

A remarkable 80-fold difference in median growth hormone (GH) values in young adult men and women was recently found in a study of sera taken in ambulatory state in the morning, after overnight fasting. In this study, the effect of ageing on morning ambulatory GH levels was investigated in 254 apparently healthy men, 21-75 years of age, and 40 women, 21-85 years. Furthermore, the effect of oestradiol on morning GH values was studied in 19 postmenopausal women, 51-79 years, treated with subcutaneous implants of 17beta-oestradiol (E2). The sera were analysed for GH, sex hormone-binding globulin (SHBG), E2, and in the men, also for testosterone (T). The morning GH levels increased (p<0.0001) with age in a group of 195 men of 41-75 years. After adjustment for age, an inverse correlation (p <0.05) was found between the levels of GH and free androgen index (T/SHBG) and a direct correlation between GH and SHBG. These relationships were more pronounced before the age of 60 than after. In the women, the GH levels decreased (p<0.01) with age and the gender difference of median values was reduced from 102-fold at younger age, 21-39 years, to 12-fold in elderly individuals, 60-75 years. In the E2-treated postmenopausal women, the morning GH values were similar to those of an untreated control group, indicating that the decrease with age in the morning GH levels in women is not a result of lower oestrogen levels alone. The gender difference in median ambulatory morning GH values decreased from 102-fold at a mean age of 25 years to 12-fold at a mean age of 68 years owing to opposite changes with age in men and women: an increase in men and a decrease in women.

Adult↗

PubMed2001

Bone mineral density in femoral neck is positively correlated to circulating insulin-like growth factor (IGF)-I and IGF-binding protein (IGFBP)-3 in Swedish men.

Studies on the hormonal regulation of bone metabolism in men have indicated covariation between insulin-like growth factor-I (IGF-I) and sex hormones with bone mineral density (BMD). In this study the relationships between BMD in total body, lumbar spine, femoral neck, distal and ultradistal (UD) radius and circulating levels of IGFs, IGF binding proteins (IGFBPs), and sex steroids were investigated in 55 Swedish men between 22 and 85 (52 +/- 18, mean +/- SD) years of age. BMD in total body, distal and UD radius, and femoral neck was positively correlated with serum IGF-I (r = 0.31 to 0.49), IGF-II (r = 0.32 to 0.48), IGFBP-3 (r = 0.37 to 0.53), and free androgen index (FAI) (r = 0.32 to 0.40), and negatively with IGFBP-1 (r = -0.37 to -0.41) and IGFBP-2 (r = -0.29 to -0.41) levels. A positive correlation was observed between BMD in femoral neck and estradiol/SHBG ratio (r = 0.34, P = 0.01). Age correlated negatively with serum IGF-I, IGF-II, IGFBP-3, FAI, estradiol/SHBG ratio, and BMD in total body, distal and UD radius, and femoral neck, and positively with IGFBP-1, IGFBP-2, and SHBG levels. According to stepwise multiple regression analyses, a combination of weight, IGFBP-3, and testosterone accounted for 43% of the variation in BMD in femoral neck, 34% in ultradistal radius and 48% in total body (P < 0.0001). These findings indicate that sex hormones and the different components of the IGF system are associated with BMD in Swedish men, suggesting that age-related changes in these systems could contribute to the development of osteoporosis in elderly men.

Absorptiometry, Photon↗

PubMed2001

Growth hormone secretion and sensitivity in men with idiopathic osteoporosis.

Previous studies have suggested that insulin-like growth factor-I (IGF-I) and its binding proteins (IGFBPs) have a pathogenetic role in idiopathic osteoporosis. To investigate this question further we compared 20 men with idiopathic osteoporosis with 12 healthy, age-matched men regarding growth hormone (GH) secretion and sensitivity. GH samples were drawn every 30 minutes for 24 hours from 12 of the patients and all controls, and cumulated GH secretion (24 hGH) was derived. Peak GH secretion (peakGH) was provoked by an insulin tolerance test. There were no differences between the groups in serum IGF-I (162 +/- 30 vs 163 +/- 47 micrograms/liter, mean +/- SD), IGFBP-3 (2474 +/- 263 vs 2568 +/- 197 micrograms/liter), 24 hGH (1.34 +/- 1.26 vs 0.79 +/- 0.43 U), or peakGH (53.0 +/- 21.5 vs 44.1 +/- 19.8 mU/liter). Patients and controls were given GH (2.4 U/day) for 1 week. Serum levels of markers for bone turnover increased significantly in both groups, with no difference in response to GH between the groups. The increase in urinary bone resorption markers was only significant in the controls. In the patients, but not in the controls, there were significant positive correlations between indices for GH secretion and markers for bone turnover at baseline and significant negative correlations with relative changes in bone markers during GH treatment. In this study no difference in GH secretion was found between men with idiopathic osteoporosis and controls, but the findings suggest that the GH/IGF-I axis could play a regulatory role in bone metabolism in men with this condition.

Adult↗

PubMed2001

Commencing growth hormone replacement in adults with a fixed low dose. Effects on serum lipoproteins, glucose metabolism, body composition, and cardiovascular function.

The safety and effects of a fixed low dose of growth hormone (GH), 0.17 mg/day was evaluated for 3 months, on glucose metabolism, serum lipids, body composition and cardiac function in 53 GH deficient adults aged 18-78 years. Body composition was determined by dual energy X-ray absorptiometry and total body water was determined by bioelectrical impedance. Echocardiography was used to assess cardiac function and bicycle ergonometry was used to determine exercise capacity. All investigations were performed at baseline and after 3 months. At 3 months, serum levels of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3 and lipoprotein (a) and lean body mass were increased (P<0.05). Total and low density lipoprotein cholesterol levels and fat mass were reduced (P<0.05). There was an increase in the serum glucose value at 120 min after an oral glucose tolerance test performed at 3 months (P<0.05), no other changes in glucose metabolism or in cardiac function were noted. Side-effects were few and mild. This fixed low-dose regime resulted in improvements in body composition and lipid profile, without causing serious side effects. This is therefore a valid method to institute GH replacement in adults.

Adult↗

PubMed1999

Decreased estradiol levels and free androgen index and elevated sex hormone-binding globulin levels in male idiopathic osteoporosis.

Estrogen deficiency is an important pathogenetic factor in female osteoporosis, and androgens are known to have anabolic effects on bone. In this study we have compared 12 men with idiopathic osteoporosis, age 27-55 years, with 12 age-matched men, with respect to serum levels of sex steroids, biochemical markers of bone turnover, bone density, and body composition. All subjects showed values within the normal range for all hormonal parameters. The patient group compared with the controls had significantly lower serum levels of estradiol (71 +/- 13 versus 85 +/- 14 pmol/liter, P < 0.03); estradiol/sex hormone-binding globulin (SHBG) ratio (22.4 +/- 12.1 versus 39.5 +/- 18.6 pmol/mg, P < 0.02); free androgen index (51.0 +/- 19.4 versus 74.1 +/- 33.1%, P < 0.05); and higher SHBG (3.7 +/- 1.6 versus 2.5 +/- 1.0 mg/liter; P < 0.04). The men with idiopathic osteoporosis had significantly lower body mass index (23.2 +/- 2.8 versus 25.9 +/- 3.3 kg/m2, P < 0.05); and a tendency to lower percentage of total body fat (14.2 +/- 5.5 versus 18.6 +/- 6.0%; P < 0.10) than the controls. Regression analyses revealed that bone mineral density in femoral neck correlated significantly and positively with the ratio estradiol/SHBG (r = 0.67; P < 0.04) and negatively with SHBG concentrations (r = -0.63; P < 0.04) in the group of patients. These findings could represent a pathogenetic mechanism in male idiopathic osteoporosis.

Absorptiometry, Photon↗