Insulin-Like Growth Factors and Metabolic Syndrome in Obese Children

IGF-1 and IGF-2 as Molecules Linked to Causes and Consequences of Obesity from Fetal Life to Adulthood: A Systematic Review

This study examines the impact of insulin-like growth factor 1 (IGF-1) and insulin-like growth factor 2 (IGF-2) on various aspects of children's health-from the realms of growth and puberty to the nuanced characteristics of metabolic syndrome, diabetes, liver pathology, carcinogenic potential, and cardiovascular disorders. A comprehensive literature review was conducted using PubMed, with a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method employing specific keywords related to child health, obesity, and insulin-like growth factors. This study reveals associations between insulin-like growth factor 1 and birth weight, early growth, and adiposity. Moreover, insulin-like growth factors play a pivotal role in regulating bone development and height during childhood, with potential implications for puberty onset. This research uncovers insulin-like growth factor 1 and insulin-like growth factor 2 as potential biomarkers and therapeutic targets for metabolic dysfunction-associated liver disease and hepatocellular carcinoma, and it also highlights the association between insulin-like growth factors (IGFs) and cancer. Additionally, this research explores the impact of insulin-like growth factors on cardiovascular health, noting their role in cardiomyocyte hypertrophy. Insulin-like growth factors play vital roles in human physiology, influencing growth and development from fetal stages to adulthood. The impact of maternal obesity on children's IGF levels is complex, influencing growth and carrying potential metabolic consequences. Imbalances in IGF levels are linked to a range of health conditions (e.g., insulin resistance, glucose intolerance, metabolic syndrome, and diabetes), prompting researchers to seek novel therapies and preventive strategies, offering challenges and opportunities in healthcare.

Insulin-Like Growth Factor-II and Ischemic Stroke-A Prospective Observational Study

Insulin-like growth factor-II (IGF-II) regulates prenatal brain development, but the role in adult brain function and injury is unclear. Here, we determined whether serum levels of IGF-II (s-IGF-II) are associated with mortality and functional outcome after ischemic stroke (IS). The study population comprised ischemic stroke cases (n = 492) and controls (n = 514) from the Sahlgrenska Academy Study on Ischemic Stroke (SAHLSIS). Functional outcome was evaluated after 3 months and 2 years using the modified Rankin Scale (mRS), and additionally, survival was followed at a minimum of 7 years or until death. S-IGF-II levels were higher in IS cases both in the acute phase and at 3-month follow-up compared to controls (p < 0.05 and p < 0.01, respectively). The lowest quintile of acute s-IGF-II was, compared to the four higher quintiles, associated with an increased risk of post-stroke mortality (median follow-up 10.6 years, crude hazard ratio (HR) 2.34, 95% confidence interval (CI) 1.56–3.49, and fully adjusted HR 1.64, 95% CI 1.02–2.61). In contrast, crude associations with poor functional outcome (mRS 3–6) lost significance after full adjustment for covariates. In conclusion, s-IGF-II was higher in IS cases than in controls, and low acute s-IGF-II was an independent risk marker of increased mortality.

Relationship between insulin-like growth factor-1, insulin resistance and metabolic profile with pre-obesity and obesity in children

OBJECTIVES

Childhood obesity is a serious medical condition with alarmingly high rates worldwide. There is controversy regarding the relationship between insulin-like growth factor-1 (IGF-1) and pediatric obesity. We investigated the relationship between IGF-1, insulin resistance and metabolic profile with childhood pre-obesity/obesity.

METHODS

The study involved 201 children aged 7-15 years, divided in three groups according to their nutritional status (International Obesity Task Force criteria): normal-weight (n=84), pre-obese (n=82), obese (n=35). Laboratory IGF-1, insulin, fasting blood glucose (FBG), lipid profile, alanine-aminotransferase (ALT), uric acid (UA), anthropometric and body composition parameters were analyzed. Body mass index and IGF-1 standard deviation score (SDS), waist-to-height ratio (WtHR) and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) score were calculated.

RESULTS

Pre-obese/obese children had significantly higher IGF-1 SDS, FBG, insulin, HOMA-IR, UA, ALT, triglycerides, and lower high-density lipoprotein cholesterol (HDL-c); obese group had higher WtHR and low-density lipoprotein cholesterol (LDL-c) compared to controls (p<0.05). In obese group, IGF-1 SDS was positively correlated with fat free/muscle mass, total body water (p<0.05) and negatively correlated with LDL-c (p<0.05). In pre-obese/obese HOMA-IR and insulin were positively correlated with age, total body fat (TBF) (p<0.05) and negatively correlated with HDL-c (pre-obese) (p<0.05). Multivariate ordinal logistic regression analyses showed that IGF-1 SDS (OR=1.94; 95%CI: 1.21-3.11), TBF (OR=1.37; 95%CI: 1.21-1.54) were predictors of nutritional status (p<0.001). FBG (OR=42.39; 95%CI: 2.31-77.2) and UA (OR=1.03; 95%CI: 1.01-1.05) were predictors of IR (p<0.001).

CONCLUSIONS

IGF-1 SDS and TBF were predictors of nutritional status. Further studies are required to clarify the role of IGF-1 in pathophysiology of obesity and its comorbidities.

Integrated Network Pharmacology Analysis and Experimental Validation to Reveal the Mechanism of Anti-Insulin Resistance Effects of Moringa oleifera Seeds

BACKGROUND AND PURPOSE

Insulin resistance (IR) is one of the factors that results in metabolic syndrome, type 2 diabetes mellitus and different aspects of cardiovascular diseases. Moringa oleifera seeds (MOS), traditionally used as an antidiabetic food and traditional medicine in tropical Asia and Africa, have exhibited potential effects in improving IR. To systematically explore the pharmacological mechanism of the anti-IR effects of MOS, we adopted a network pharmacology approach at the molecular level.

METHODS

By incorporating compound screening and target prediction, a feasible compound-target-pathway network pharmacology model was established to systematically predict the potential active components and mechanisms of the anti-IR effects of MOS. Biological methods were then used to verify the results of the network pharmacology analysis.

RESULTS

Our comprehensive systematic approach successfully identified 32 bioactive compounds in MOS and 44 potential targets of these compounds related to IR, as well as 37 potential pathways related to IR. Moreover, the network pharmacology analysis revealed that glycosidic isothiocyanates and glycosidic benzylamines were the major active components that improved IR by acting on key targets, such as SRC, PTPN1, and CASP3, which were involved in inflammatory responses and insulin-related pathways. Further biological research demonstrated that the anti-IR effects of MOS were mediated by increasing glucose uptake and modulating the expression of SRC and PTPN1.

CONCLUSION

Our study successfully predicts the active ingredients and potential targets of MOS for improving IR and helps to illustrate mechanism of action at a systemic level. This study not only provides new insights into the chemical basis and pharmacology of MOS but also demonstrates a feasible method for discovering potential drugs from traditional medicines.

Effect of prenatal bisphenol A exposure on early childhood body mass index through epigenetic influence on the insulin-like growth factor 2 receptor (IGF2R) gene

OBJECTIVES

Epigenetic mechanisms have been suggested to play a role in the link between in utero exposure to bisphenol A (BPA) and pediatric obesity; however, there is little evidence regarding this mechanism in humans. We obtained data on obesity-associated CpG sites from a previous epigenome-wide association study, and then examined whether methylation at those CpG sites was influenced by prenatal BPA exposure. We then evaluated the relationship between CpG methylation status and body mass index (BMI) in a prospective children's cohort at ages 2, 4, 6, and 8 years.

METHODS

Methylation profiles of 59 children were longitudinally analyzed at ages 2 and 6 years using the Infinium Human Methylation BeadChip. A total of 594 CpG sites known to be BMI or obesity-associated sites were tested for an association with prenatal BPA levels, categorized into low and high exposure groups based on the 80th percentile of maternal BPA levels (2.68 μg/g creatinine), followed by an analysis of the association between DNA methylation and BMI from ages 2-8.

RESULTS

There was a significant increase in the methylation levels of cg19196862 (IGF2R) in the high BPA group at age 2 years (p = 0.00030, false discovery rate corrected p < 0.10) but not at age 6. With one standard deviation increase of methylation at cg19196862 (IGF2R) at age 2 years, the linear mixed model analysis revealed that BMI during ages 2-8 years significantly increased by 0.49 (95% confidence interval; 0.08, 0.90) in girls, but not in boys. The indirect effect of prenatal BPA exposure on early childhood BMI through methylation at cg19196862 (IGF2R) at age 2 years was marginally significant.

CONCLUSIONS

Prenatal exposure to BPA may influence differential methylation of IGF2R at age 2. This result indicates that a possible sensitive period of DNA methylation occurs earlier during development, which may affect BMI until later childhood in a sex-specific manner.

A prospective case-control study on miRNA circulating levels in subjects born small for gestational age (SGA) evaluated from childhood into young adulthood

OBJECTIVE

microRNAs (miRNAs) associated with metabolic risk have never been extensively investigated in SGA subjects. The aim of the current study was to evaluate miRNAs in SGA and AGA subjects and their relationships with the metabolic status and growth.

DESIGN AND METHODS

A prospective longitudinal case-control study was performed in 23 SGA with postnatal catch-up growth and 27 AGA subjects evaluated at the age of 9 and 21 years. Circulating levels of miR-122-5p, miR-16-5p, miR-126-3p, and miR-486-5p were assessed by qPCR.

RESULTS

SGA subjects were shorter both at 9 and at 21 years. No significant differences in insulin like growth factors and metabolic profile were found with the exception of basal glycemia at 9 years. miRNA levels did not differ between SGA and AGA subjects, at 9 and 21 years. miR-16-5p and miR-126-3p levels were higher at 9 than at 21 years. In SGA subjects, miR-122-5p at 9 years was inversely related to adiponectin levels at 21 years and miR-486-5p at 9 years was inversely related to whole-body insulin sensitivity at 9 years and directly related to Hb1Ac at 21 years. Regression analyses showed no predictive value of miRNAs for growth parameters in neither SGA nor AGA subjects.

CONCLUSIONS

SGA with postnatal catch-up growth did not show any difference in metabolic risk markers or miRNA circulating levels compared to AGA controls in childhood and young adulthood. miR-122-5p during childhood could identify SGA subjects at higher risk of developing insulin resistance and, eventually, type 2 diabetes in adulthood but further studies are needed to confirm it.

Skipping Breakfast Is Associated with an Atherogenic Lipid Profile in Overweight and Obese Prepubertal Children

BACKGROUND

Skipping breakfast has been associated with a higher risk of obesity and cardiovascular (CV) risk factors. However, it is not known if skipping breakfast is also correlated with CV risk factors independently from obesity. The mechanisms explaining the role of skipping breakfast on promoting fat accumulation as well as CV risk are not known. Hormones, in particular, insulin-like growth factor-1 (IGF-1), may potentially play a role in the metabolic profile of breakfast skippers.

AIM

This cross-sectional study aims to test, in a sample of overweight/obese children, the hypotheses that skipping breakfast is associated with a worse metabolic profile and that IGF-1 levels are associated with this unfavorable metabolic profile.

METHODS AND RESULTS

We enrolled 112 overweight/obese prepubertal children (3-12 years). Anthropometric characteristics (height SDS, weight SDS, and body mass index (BMI) z-score) were measured. Blood samples were collected to evaluate glucose and lipid metabolisms and hormone profile (growth hormone (GH), IGF-1, insulin, and cortisol). The triglycerides/high-density lipoprotein (HDL) cholesterol ratio was calculated as a predictor of cardiovascular risk. Children were divided into two groups according to breakfast habits: consumers (≥5 weekly; N = 76) and skippers (≤4 weekly; N = 36). Glycaemia, total and low-density lipoprotein (LDL) cholesterol, triglycerides (p < 0.05), and triglycerides/HDL cholesterol ratio (p < 0.001) were higher, while HDL cholesterol was lower (p < 0.01) in skippers as compared to consumers. IGF-1 concentrations were inversely correlated with LDL cholesterol (r = -0.279, p=0.013) and directly correlated with HDL cholesterol (r = 0.226, p=0.047). IGF-1 correlated positively with HDL cholesterol (r = 0.266, p=0.045) in consumers and correlated negatively with LDL cholesterol (r = -0.442, p=0.024) in skippers. Breakfast consumption among prepubertal overweight/obese children showed a better lipid profile in comparison with those who skipped breakfast [OR: 0.165 (95% CI: 0.053-0.518), p=0.001]; these latter odds of the increased triglycerides/HDL cholesterol ratio was 6.1-fold higher.

CONCLUSIONS

Breakfast skippers show a worse lipid profile when compared to breakfast consumers. IGF-1 might play a role as an independent modulator of lipid metabolism.