Effect of One-Year Growth Hormone Therapy on Cardiometabolic Risk Factors in Boys with Obesity

U-Shaped relationship of insulin-like growth factor I and incidence of nonalcoholic fatty liver in patients with pituitary neuroendocrine tumors: a cohort study

Context

Although the role of insulin-like growth factor I (IGF-1) in nonalcoholic fatty liver disease (NAFLD) has garnered attention in recent years, few studies have examined both reduced and elevated levels of IGF-1.

Objective

The aim of this study was to examine the potential relationship between IGF-1 levels and the risk of new-onset NAFLD in patients with pituitary neuroendocrine tumors (PitNET).

Methods

We employed multivariable Cox regression models and two-piecewise regression models to assess the association between IGF-1 and new-onset NAFLD. Hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs) were calculated to quantify this association. Furthermore, a dose-response correlation between lgIGF-1 and the development of NAFLD was plotted. Additionally, we also performed subgroup analysis and a series sensitivity analysis.

Results

A total of 3,291 PitNET patients were enrolled in the present study, and the median duration of follow-up was 65 months. Patients with either reduced or elevated levels of IGF-1 at baseline were found to be at a higher risk of NAFLD compared to PitNET patients with normal IGF-1(log-rank test, P < 0.001). In the adjusted Cox regression analysis model (model IV), compared with participants with normal IGF-1, the HRs of those with elevated and reduced IGF-1 were 2.33 (95% CI 1.75, 3.11) and 2.2 (95% CI 1.78, 2.7). Furthermore, in non-adjusted or adjusted models, our study revealed a U-shaped relationship between lgIGF-1 and the risk of NAFLD. Moreover, the results from subgroup and sensitivity analyses were consistent with the main results.

Conclusions

There was a U-shaped trend between IGF-1 and new-onset NAFLD in patients with PitNET. Further evaluation of our discoveries is warranted.

Physiological response of endurance exercise as a growth hormone mediator in adolescent women's

OBJECTIVES

Overweight status decreases the growth hormone (GH) secretion, thus, increasing the risk factors for medical complications. However, proper exercise is reported to enhance GH and affect the energy balance. Therefore, exercise is proclaimed to be an accurate and engaging therapy to increase GH in preventing overweight. This study aims to investigate the physiological response of exercise in mediating the increase of GH secretion in female adolescents.

METHODS

22 overweight women aged 19-20 years old, with maximal oxygen consumption of 27-35 mL/kg/min, were selected as sample size. They were divided into three groups, namely (CONT, n=7) Control, (MIEE, n=7) Moderate-intensity interval endurance exercise, and (MCEE, n=8) Moderate-intensity continuous endurance exercise. The exercise was carried out by running for 30-35 min using treadmills with an intensity of 60-70% HR_max. The blood sampling for GH examination was carried out four times before exercise, 10 min, 6 h, and 24 h after exercise. The enzyme-linked immunosorbent assay (ELISA) was used to measure the GH and IGF-1 levels. The data analysis was carried out using a one-way ANOVA test, with a significance level of 5%.

RESULTS

The results of the one-Way ANOVA test suggested a significantly different average GH and IGF-1 before and after the exercise between the three groups (CON, MIEE, and MCEE) (p≤0.05).

CONCLUSIONS

MCEE increases the GH and IGF-1 levels more considerably than MIEE. Therefore, exercise is a mediator to increase GH and IGF-1 secretion in overweight individuals. Exercise could be a viable therapy for overweight people.

Effects of growth hormone on lipid metabolism and sexual development in pubertal obese male rats

To investigate the effects of growth hormone (GH) on pubertal obese male rats, a rat model of high-fat diet-induced obesity was established in juvenile male rats. The model rats were divided into the treatment group (GH) and the non-treatment group (physiological saline). After 4 weeks, we measured the levels of alanine transaminase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglycerides (TGs), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), estrogen (E2), testosterone (T), and insulin-like growth factor (IGF-1). The morphological changes of the liver and testis were assessed, and the expression of aromatase was detected. The levels of ALT, AST, TC, TG, LDL-C, E2, and IGF-1 in the treatment group were significantly lower than in the non-treated model rats (P < 0.001). The levels of HDL-C and T of GH-treated rats were significantly higher than those of the non-treatment group (P < 0.001). Compared with non-treated model rats, GH-treated model rats showed reduced liver steatosis, improved morphological structure of the testicular seminiferous tubules, and an increased number of spermatogenic cells. The treatment group also showed lower expression of aromatase in the liver and testis compared with the non-treatment group. GH partially protected pubertal male rats from obesity-induced lipid metabolic disorder and sexual retardation.