LEPR polymorphism may affect energy balance during weight loss among Brazilians obese adolescents

Association of polymorphism in leptin receptor gene with susceptibility of adolescent idiopathic scoliosis

PURPOSE

Abnormal leptin bioavailability has play key roles in the etiology of adolescent idiopathic scoliosis (AIS). Both leptin and its receptor levels may be modulated by the presence of genetic polymorphisms. This study aimed to evaluate the role of polymorphisms in the leptin (LEP) and its main receptor (LEPR) genes in the AIS susceptibility in girls.

METHODS

A retrospective case-control study was conducted with 189 AIS and 240 controls. LEP rs2167270 and LEPR rs2767485 polymorphisms were genotyped using a TaqMan validated assay. Associations were evaluated by odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

The AIS group showed a predominance of girls under 18 years old (n = 140, 74.1%), 148 (78.3%) had low or normal BMI, 111 (58.7%) had Cobb ≥ 45º and 130 (68.7%) were skeletally mature. Minor allele frequencies of rs2167270 and rs2767485 were 35.7% and 18.3%, for AIS and 35.6% and 25.4% for controls, respectively. LEPR rs2767485 T and TC + TT were associated with higher risk of AIS (OR = 1.53; 95% CI = 1.09-2.13 and OR = 1.84; 95% CI = 1.69-2.01, respectively), since CC genotype was only present in the control group. In addition, the LEP rs2167270 GA + AA was more frequent in low weight group (BMI ≤ 24.9) of girls with AIS. There was no significant association between LEP rs2167270 and AIS susceptibility, and LEPR rs2767485 and BMI.

CONCLUSION

The LEPR rs2767485 was associated with the genetic susceptibility of AIS and LEP rs2167270 with low BMI. These data can contribute to the identification of genetic biomarkers to improve the diagnosis and treatment.

Gene variants and the response to childhood obesity interventions: A systematic review and meta-analysis

BACKGROUND

Multiple lifestyle-based childhood obesity interventions have been conducted to address childhood obesity, but individual's response to the universal intervention approach varied greatly. Whether gene variants related to children and adolescents' varied responses to obesity interventions remained unclear.

AIMS

To determine the associations of gene variants with the changes in obesity- and metabolism-related indicators after obesity interventions in children and adolescents.

METHODS

Ten databases and registers (including grey literature) were searched. The lifestyle-based obesity interventions in children and adolescents (≤18 years) that reported the changes in obesity- (body mass index (BMI), BMI Z-score, waist circumference (WC), waist-to-hip ratio (WHR), etc) and metabolism-related (glucose, cholesterol, etc) indicators by genotype after interventions were included. Our primary outcome was the mean difference of the changes in BMI Z-score by genotype after interventions, and secondary outcomes were changes in the remaining obesity- and metabolism-related indicators after interventions. We used the random-effects model to synthesize the results.

RESULTS

This review included 50 studies (15,354 children and adolescents with overweight/obesity) covering 102 genes and 174 single nucleotide polymorphisms (SNPs). Approximately three-quarters of SNPs showed no evidence of association with the changes in obesity- or metabolic-related indicators after interventions. One quarter of SNPs were minorly associated with the changes in the BMI Z-score (median effect size: 0.001) with little clinical significance. Only 6 (12 %) studies focused on the accumulated effect of multiple gene variants.

CONCLUSIONS

Gene variants that have been explored appear to play a minor role in lifestyle-based obesity interventions in children and adolescents. More high-quality studies based on the design of randomized controlled trials are needed to examine the accumulated effect of multiple gene variants in childhood obesity interventions.

PROSPERO REGISTRY NUMBER

This systematic review and meta-analysis was registered at PROSPERO as CRD42022312177.

The Genetic Basis of Childhood Obesity: A Systematic Review

Overweight and obesity in childhood and adolescence represents one of the most challenging public health problems of our century owing to its epidemic proportions and the associated significant morbidity, mortality, and increase in public health costs. The pathogenesis of polygenic obesity is multifactorial and is due to the interaction among genetic, epigenetic, and environmental factors. More than 1100 independent genetic loci associated with obesity traits have been currently identified, and there is great interest in the decoding of their biological functions and the gene-environment interaction. The present study aimed to systematically review the scientific evidence and to explore the relation of single-nucleotide polymorphisms (SNPs) and copy number variants (CNVs) with changes in body mass index (BMI) and other measures of body composition in children and adolescents with obesity, as well as their response to lifestyle interventions. Twenty-seven studies were included in the qualitative synthesis, which consisted of 7928 overweight/obese children and adolescents at different stages of pubertal development who underwent multidisciplinary management. The effect of polymorphisms in 92 different genes was assessed and revealed SNPs in 24 genetic loci significantly associated with BMI and/or body composition change, which contribute to the complex metabolic imbalance of obesity, including the regulation of appetite and energy balance, the homeostasis of glucose, lipid, and adipose tissue, as well as their interactions. The decoding of the genetic and molecular/cellular pathophysiology of obesity and the gene-environment interactions, alongside with the individual genotype, will enable us to design targeted and personalized preventive and management interventions for obesity early in life.

Association between LEPR polymorphism and susceptibility of osteoporosis in Chinese Mulao people

To explore the association between the single nucleotide polymorphism (SNP) of leptin receptor (LEPR) gene and the susceptibility to osteoporosis (OP) among Chinese Mulao people. A total of 738 people were involved. Bone mineral density (BMD) was examined by calcaneus ultrasound attenuation measurement. Six SNPs of LEPR were detected. The genotypes, allele frequencies, linkage disequilibrium, and haplotype were analyzed. BMD decreased with age and males had higher BMD than women. The proportion of normal bone mass decreased with age, and morbidity of OP increased. Three out of six SNPs showed a difference between OP and normal group. Individuals with AA genotype of rs1137100 in OP group outnumber the normal group, AA increased the risk of OP. In rs2767485, CT increased the risk of OP, C allele may be susceptible to OP. TT genotype of rs465555 was susceptible genotype of OP, T locus may be associated with OP. Strong linkage disequilibrium was detected among rs1137100, rs1137101, and rs4655555. Four haplotypes were constructed, among which, AACGCT and GGTGTA increased the risk of OP by 3.9 and 4.2 times, respectively, whereas, GGCGTA reduced 74% of OP susceptibility. The rs1137100, rs2767485, and rs465555 of LEPR were associated with OP in Chinese Mulao people.

Adipocytokine and appetite-regulating hormone response to weight loss in adolescents with obesity: Impact of weight loss magnitude

OBJECTIVE

The aim of this study was to investigate the association between the magnitude of weight loss (WL) and serum concentrations of the main adipocytokines and appetite-regulating hormones in adolescents with obesity.

METHODS

After completion of informed consent,108 adolescents with obesity (14-19 y of age; postpubertal) were submitted to clinical, nutritional, psychological, physical exercise, and physiotherapy support for 1 y. Body composition (BC) and plasma levels of neuropeptides (neuropeptide Y [NPY], agouti-related peptide [AgRP], and α-melanocyte-stimulating hormone [α-MSH]) and leptin were measured at baseline and post-intervention.

RESULTS

After therapy, adolescents who lost <10% body weight and <10% body weight (were compared. Both groups presented improvements in BC and reduced leptin. The Δα-MSH, Δα-MSH/AgRP ratio, and Δα-MSH/NPY ratio were lower and AgRP and NPY variations were higher in the low weight loss group. The leptin concentration was close to normal in the high weight loss only. The ΔWeight, Δα-MSH and Δleptin were associated with body fat loss by multiple linear regressions for all samples.

CONCLUSION

Weight loss >10% seems to reverse obesity-induced hyperleptinemia while stabilizing the neuropeptides that control appetite in adolescents with obesity. We were able to produce a prognostic mathematical model to predict body fat loss using weight, leptin, and α-MSH variations.

Deletion of growth hormone receptor in hypothalamic neurons affects the adaptation capacity to aerobic exercise

The hypothalamus mediates important exercise-induced metabolic adaptations, possibly via hormonal signals. Hypothalamic leptin receptor (LepR)- and steroidogenic factor 1 (SF1)-expressing neurons are directly responsive to growth hormone (GH) and deletion of GH receptor (GHR) in these cells impairs neuroendocrine responses during situations of metabolic stress. In the present study, we determined whether GHR ablation in LepR- or SF1-expressing cells modifies acute and chronic metabolic adaptations to exercise. Male mice carrying deletion of GHR in LepR- or SF1-expressing cells were submitted to 8 weeks of treadmill running training. Changes in aerobic performance and exercise-induced metabolic adaptations were determined. Mice carrying GHR deletion in LepR cells showed increased aerobic performance after 8 weeks of treadmill training, whereas GHR ablation in SF1 cells prevented improvement in running capacity. Trained mice carrying GHR ablation in SF1 cells exhibited increased fat mass and reduced cross-sectional area of the gastrocnemius muscle. In contrast, deletion of GHR in LepR cells reduced fat mass and increased gastrocnemius muscle hypertrophy, energy expenditure and voluntary locomotor activity in trained mice. Although glucose tolerance was not significantly affected by targeted deletions, glycemia before and immediately after maximum running tests was altered by GHR ablation. In conclusion, GHR signaling in hypothalamic neurons regulates the adaptation capacity to aerobic exercise in a cell-specific manner. These findings suggest that GH may represent a hormonal cue that informs specific hypothalamic neurons to produce exercise-induced acute and chronic metabolic adaptations.