Growth hormone/insulin-like growth factor-1 axis, calciotropic hormones and bone mineral density in young patients with chronic viral hepatitis.

INTRODUCTION: Chronic liver disease caused by HBV and HCV infections, due to its great prevalence and serious medical consequences, is at the present time a significant clinical problem. An impaired liver function can provoke severe disturbances in calcium and phosphorus homeostasis, and consequently in the bone metabolism resulting in hepatic osteodystrophy. The aim of this study was to determine whether there are significant differences in bone mineral density (BMD) and/or circadian levels of hormones connected with bone metabolism and bone turnover markers in patients with chronic viral hepatitis. MATERIAL AND METHODS: Circadian levels (AUC, area under the curve) of GH, IGF-I, IGFBP-3, osteocalcin (BGLAP), C-terminal telopeptide of type I collagen (ICTP), PTH, 25(OH)D, total calcium and total phosporus were measured in the blood of members of the study group (n = 80). BMD was assessed using the dual-energy X-ray absorptiometry method of the L2-L4 lumbar spine. Data was compared to that of healthy individuals (n = 40). RESULTS: BMD (1.05 g/cm3 vs. 1.20 g/cm3), total calcium concentration (2.20 mmol/L vs. 2.45 mmol/L), total phosphorus concentration (1.06 mmol/L vs. 1.33 mmol/L), IGF-I (AUC 3,982.32 ng/mL vs. 5,167.61 ng/mL), IGFBP-3 (AUC 725.09 ng/L vs. 944.35 ng/L), 25(OH)D (AUC 356.35 ng/mL vs. 767.53 ng/mL) and BGLAP (AUC 161.39 ng/L vs. 298 ng/L) were lower in the study group. GH (AUC 88.3 ng/mL vs. 48.04 ng/mL), iPTH (AUC 1,201.94 pg/mL vs. 711.73 pg/mL) and ICTP (AUC 104.30 µg/L vs. 54.49 µg/L) were higher in patients with hepatitis. Positive correlations were noted between bone mineral density and IGF-I, IGFBP-3, and BGLAP levels. CONCLUSIONS: Chronic viral hepatitis causes a decrease in bone mineral density. Impaired liver function disrupts homeostasis of the calcium- vitamin D-parathyroid hormone axis and provokes secondary hyperparathyroidism. Chronic viral hepatitis induces a decrease in the synthesis of IGF-I and IGFBP-3 and an increase in GH secretion. Hepatic osteodystrophy is probably caused by both changes in calciotropic hormones as well as in the somatotropin hormone axis.

[Serum adiponectin levels in patients with acromegaly]. / Stezenie adiponektyny w surowicy chorych na akromegalie.

UNLABELLED: Acromegaly is frequently associated with impaired glucose tolerance or diabetes. Insulin resistance has been reported to be related to low levels of adiponectin, which is exclusively produced by adipose tissue, as well as to decreased concentration of sex hormone binding globuline (SHBG). Growth hormone (GH) excess is associated with increased muscle mass and decreased fat mass. Influence of GH on production and secretion of adiponectin is not completely understood. The aims of this study were to assess serum adiponectin levels in patients with active acromegaly and to compare them with concentrations in the control group and to investigate relationships between adiponectin and indexes: body mass index (BMI) and waist-to-hip ratio (WHR) as well as SHBG levels. MATERIALS AND METHODS: Serum adiponectin and SHBG levels were measured by radioimmunoassay in 30 patients with active acromegaly and in 22 sex-, age-, BMI- and WHR-matched controls. The groups were comparable in prevalence of hypertension and disturbances of glucose metabolism. RESULTS: Serum adiponectin concentrations were higher in acromegalic patients compared with control group (24.03 +/- 9.85 mg/ml vs. 14.46 +/- 3.96 mg/ml, p<0.001). When the subjects were fallen into two groups according to sex, significant differences were also observed. Serum SHBG levels were lower in cases compared with controls (25.36 +/- 22.89 nmol/l vs. 33.54 +/- 15.07 nmol/l, p=0.03). In the control group we found adiponectin positively correlated with SHBG concentrations (r=0.53, p=0.01) and negatively correlated with BMI (r=-0.52, p=0.02) and WHR (r=-0.51, p=0.03). However, these relationships were not observed in patients with acromegaly. No significant associations were found between adiponectin and GH or IGF-I. CONCLUSIONS: Serum concentration of adiponectin is significantly higher in patients with acromegaly when compared with the control group and is independent of BMI, WHR and SHBG. The results suggest that adiponectinemia does not directly affect development of insulin resistance in acromegaly.

Effect of postmenopause and hormone replacement therapy on serum adiponectin levels.

Little is known about the effects of menopause and hormone replacement therapy (HRT) on adiponectin production. The objectives of the study were to compare levels of serum adiponectin in post- and premenopausal women, to test whether adiponectin levels are related to endogenous estradiol and sex hormone-binding globulin (SHBG) levels, to determine whether HRT influences serum adiponectin, and to investigate relationships of adiponectin levels with cardiovascular risk factors. One hundred four women matched for body mass index were enrolled in this study, and among them were 34 postmenopausal HRT nonusers, 34 postmenopausal HRT users, and 36 premenopausal healthy women with regular menstrual cycles. We evaluated waist circumference and waist-to-hip ratio (WHR) in each women. Serum was assayed for adiponectin, estradiol, SHBG, triglycerides (TGs), total cholesterol, high-density lipoprotein cholesterol, and fasting glucose levels. Post- and premenopausal women showed no significant differences in adiponectin and SHBG concentrations. There were no differences in serum adiponectin levels between postmenopusal HRT nonusers and users; however, SHBG concentrations were higher in HRT users. The simple linear regression analyses of all studied women indicated that serum adiponectin was negatively correlated with body mass index, waist circumference, WHR, and TG levels. Positive correlation was observed between adiponectin and high-density lipoprotein cholesterol as well as between adiponectin and SHBG levels. There were no relationships between adiponectin and estradiol levels in all studied women and among subgroups. Multiple regression analysis showed that WHR and TG were significant independent predictors of serum adiponectin. In conclusion, serum adiponectin levels are not influenced by menopausal status or serum estradiol levels. Exogenous estrogen treatment does not significantly affect serum adiponectin concentrations.

[Quantitative assessment of mRNA TGF-beta1 in liver tissue in connection with serum mean daily level of TGF-1 in chronic hepatitis B patient]. / Ocena ilosciowa mRNA TGF-beta1 w bioptacie watroby w powiazaniu ze sredniodobowym steeniem TGF-beta1 w surowicyz u chorych z przewleklym zapaleniem watroby typu B.

Monitoring of fibrosis process with the use of histopathologic studies on liver's bioptates is limited, so it is attempted to find reliable, obtained with less invasive methods, sensitive and reflecting fibrosis dynamics markers of this process. The aim of the study was simultaneously to assess liver's expression as well as circadian and mean daily TGF-betal concentration in serum of patients with chronic hepatitis type B in comparison to control group. Studies were performed on 50 patients (9 women, 41 men) aged 45.9 +/- 2.3 years with chronic hepatitis type B. Control group consisted of 20 patients (mean age 38.6 +/- 3.7 years), in which so called minimal changes without fibrosis were observed in histophatologic bioptate of liver. Blood for studies was collected every 4 houres during the day. Serum concentration of TGF-betal was assessed with the use of ELISA method, and expression of mRNA TGF-betal in liver with QRT-PCR method. No significant difference between circadian as well as mean daily serum TGF-betal concentration beetwen control group and the group with chronic hepatitis type B was shown. Increased expression of mRNA, TGF-betal in bioptate of liver of patients with chronic hepatitis type B in comparison to control group was noted. In "minimal changes" control group presence of significant positive correlation between expression of mRNA TGF-beta1 in liver and concentration of this cytokine in serum was shown, in the group of patients with chronic hepatitis B this connection was not noted.

[Cardiovascular effects of growth hormone deficiency in adults]. / Niedobór hormonu wzrostu u doroslych a uklad sercowo-naczyniowy.

The role of growth hormone (GH) in maintaining normal cardiovascular function and the influence of GH deficiency and GH replacement therapy on cardiovascular risk are presented.