GH Resistance Is a Component of Idiopathic Short Stature: Implications for rhGH Therapy

Short-acting growth hormone supplementation for bone age and growth rate in children with idiopathic short stature: a meta-analysis

OBJECTIVE

To explore the effect of short-acting growth hormone (GH) supplementation on bone age and growth rate of children with idiopathic short stature.

METHODS

The authoritative databases such as PubMed, Medline, and Web of Science were extensively searched through the systematic and comprehensive literature retrieval strategy to compile the clinical research data on the treatment of idiopathic short stature with short-acting GH. The study will be strictly screened to ensure that all enrolled research subjects are patients with idiopathic short stature, and the intervention method is defined as short-acting GH replacement therapy, and a reasonable control group is set, such as placebo treatment, to ensure the scientificity and comparability of research results. Outcome index data such as basic characteristics, sample size, follow-up time, and total effective rate of the included studies were extracted. In this study, RevMan 5.3, a professional statistical software tool, was used to systematically perform the meta-analysis process. Weighted average difference (WMD) was calculated as the primary outcome to evaluate the effect of bone age and growth rate, and the WAD in adverse reactions was considered as the secondary outcome.

RESULTS

Nine studies were included in the study, and 491 patients with idiopathic short stature were included in the study. The results of the meta-analysis showed that there was no significant difference in bone age but a significant difference in growth rate when compared with the control group.

CONCLUSION

Short-acting GH supplementation can significantly improve the growth rate of children with idiopathic short stature, but has little effect on bone age.

[Discussion on the genetic mechanisms and efficacy of growth hormone therapy in children with idiopathic short stature]

Idiopathic short stature (ISS) is a term that encompasses a group of short stature disorders with unknown etiology. The genetic factors associated with ISS are complex, and the known genetic mechanisms include alterations in hormones, hormone receptors, or related pathways, defects in fundamental cellular processes (such as intracellular signaling pathways and transcriptional regulation), issues with extracellular matrix or paracrine signaling, as well as genetic variations in the genes encoding these proteins. Recombinant human growth hormone (rhGH) therapy is currently an effective clinical method for improving height in children with ISS. However, the efficacy of rhGH treatment on ISS varies among children with different genetic mechanisms. This paper analyzes and elucidates the genetic mechanisms of ISS and the effects of rhGH on ISS based on existing clinical research, aiming to enhance the understanding of ISS and provide references for improving the height of these children.

Ghrelin alleviated TiO2 NPs-induced inhibition of endochondral osteogenesis and promoted longitudinal growth of long bones in juvenile rats via Wnt/β-catenin signaling pathway

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in children's daily necessities and foods, and their health hazards to children have attracted particular attention. Childhood is a critical time for accelerated bone growth and development. Current studies revealed that TiO2 NPs exposure causes bone damage in juvenile rats; however, the underlying mechanism is unknown. Ghrelin is a polypeptide hormone that is considered to be a candidate factor for regulating bone growth and development. In this research, 3-week-old juvenile male rats were administered 0, 100 or 200 mg/kg TiO2 NPs and 50 μg/kg ghrelin for 4 weeks to explore the underlying mechanism of TiO2 NPs-induced bone damage, and the protective effect of ghrelin. Our results revealed that TiO2 NPs resulted in decreased synthesis of bone growth-related hormones, disturbed bone metabolism, and destruction of bone structure. Further mechanism studies showed that TiO2 NPs inhibited Wnt/β-catenin pathway, reduced collagen synthesis, inhibited chondrocyte proliferation and differentiation, promoted chondrocyte apoptosis, and inhibited endochondral osteogenesis, ultimately leading to long bone longitudinal growth retardation and osteoporosis. Ghrelin alleviated the negative effects of TiO2 NPs-induced bone growth in juvenile rats by upregulating the Wnt/β-catenin signaling pathway. This study provided a reference for the clinical treatment of growth retardation and idiopathic short stature in juvenile children caused by environmental pollutants.

Liver impact of growth hormone (GH) intermittent treatment during the growth period in mice

Liver impact of prolonged GH-treatment given to non-GH-deficient growing mice between the third and eighth week of life was evaluated in both sexes. Tissues were collected 6 h after last dose or four weeks later. Somatometric, biochemical, histological, immunohistochemical, RT-qPCR and immunoblotting determinations were performed. Five-week GH intermittent administration induced body weight gain and body and bone length increase, augmented organ weight, higher hepatocellular size and proliferation, and increased liver IGF1 gene expression. Phosphorylation of signaling mediators and expression of GH-induced proliferation-related genes was decreased in GH-treated mice liver 6h after last injection, reflecting active sensitization/desensitization cycles. In females, GH elicited EGFR expression, associated to higher EGF-induced STAT3/5 phosphorylation. Four weeks after treatment, increased organ weight concomitant to body weight gain was still observed, whereas hepatocyte enlargement reverted. However, basal signaling for critical mediators was lower in GH-treated animals and in male controls compared to female ones, suggesting signaling declination.

Association between the uric acid to high density lipoprotein cholesterol ratio and alanine transaminase in Chinese short stature children and adolescents: A cross-sectional study

Objective

Uric acid to high-density lipoprotein cholesterol ratio (UHR), the ratio of uric acid to high-density lipoprotein cholesterol, is a newly proposed marker of metabolic abnormalities. There are few previous studies directly investigating the relationship between UHR and alanine aminotransferase (ALT), especially in short stature populations, however, short stature children and adolescents are more likely to have metabolic disorders. This research aimed to investigate the relationship between the UHR and ALT in children and adolescents with short stature.

Methods

In this cross-sectional analysis, the clinical data of 1,510 children with height below -2 SD who were evaluated at the Department of Endocrinology, Affiliated Hospital of Jining Medical University from 1 March 2013 to 31 December 2021, were selected. Anthropometric and biochemical indicators were measured. The relationship between UHR and ALT was analysed.

Results

The univariate analysis results showed that UHR was positively associated with ALT (β = 0.43, P < 0.0001). Furthermore, after adjusting for possible confounding factors, a non-linear relationship was detected between UHR and ALT through smooth curve fitting, and the inflection point of UHR was 10.93% after multivariate piecewise linear regression analysis. ALT increased with UHR elevation when the UHR was greater than 10.93% (β = 0.69, 95% CI 0.39, 0.98; P < 0.0001). However, we did not observe a significant relationship when the UHR was less than 10.93% (P = 0.9229).

Conclusion

Our study demonstrated that in Chinese children and adolescents with short stature, UHR may be associated with the regulation of ALT levels, and this relationship merits further investigation.

Children With Short Stature Display Reduced ACE2 Expression in Peripheral Blood Mononuclear Cells

BACKGROUND

The cause of short stature remains often unknown. The renin-angiotensin system contributes to growth regulation. Several groups reported that angiotensin-converting enzyme 2 (ACE2)-knockout mice weighed less than controls. Our case-control study aimed to investigate if children with short stature had reduced ACE2 expression as compared to controls, and its significance.

MATERIALS AND METHODS

children aged between 2 and 14 years were consecutively recruited in a University Hospital pediatric tertiary care center. Cases were children with short stature defined as height SD ≤ -2 diagnosed with growth hormone deficiency (GHD) or idiopathic short stature (ISS), before any treatment. Exclusion criteria were: acute diseases, kidney disease, endocrine or autoimmune disorders, precocious puberty, genetic syndromes, SGA history. ACE and ACE2 expression were measured in peripheral blood mononuclear cells, angiotensins were measured by ELISA.

RESULTS

Children with short stature displayed significantly lower ACE2 expression, being 0.40 fold induction (0.01-2.27) as compared to controls, and higher ACE/ACE2, with no differences between GHD and ISS. ACE2 expression was significantly and inversely associated with the risk of short stature, OR 0.26 (0.07-0.82), and it had a moderate accuracy to predict it, with an AUC of 0.73 (0.61-0.84). The cutoff of 0.45 fold induction of ACE2 expression was the value best predicting short stature, identifying correctly 70% of the children.

CONCLUSIONS

Our study confirms the association between the reduction of ACE2 expression and growth retardation. Further studies are needed to determine its diagnostic implications.