Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic lowgrade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

Fat Distribution and Differential Effects on Metabolic Liver Fat Infiltration in Young Mexicans in Reynosa, Mexico: A Collaborative Study across the U.S.-Mexico Border

Introduction: Metabolic-associated fatty liver disease (MAFLD) is a descriptive term for NAFLD (Non-alcoholic) physiopathology associated with obesity. The age of onset linked to body fat distribution is poorly studied. Therefore, we aimed to assess the body fat effect on liver fat infiltration and stiffness (LSt) mediated by insulin resistance (IR). Methods: After obtaining informed consent, five hundred freshmen from two universities in Reynosa, Mexico (UMAN & UAT) were enrolled in the study. They completed a questionnaire focused on familial cardiometabolic risk and provided anthropometric measurements. In a subset of N=200, we obtained blood samples for biochemical measurements, body fat percentage (BF%) by bioimpedance, LSt (kPa), and fat infiltration (Continued Attenuation Parameter, CAP) by elastography. We used mediation analysis with structural equation models (Stata v16.1) to determine the relationship between BMI, BF%, and abdominal obesity with IR and liver stiffness and fat infiltration. The term “-\u3e” means ‘explain’ or ‘cause’. Results: We found that AO-\u3eIR (standardized values b=0.53, p=0.005), AO-\u3eCAP (b=0.69, pIR (b=0.23, p=0.007). BMI did not have an effect on CAP or IR. Also, BMI-\u3eLS (b=0.47, p=0.05) but AO-\u3eLS was absent. Finally, there was a bidirectional relationship between LS and IR [LS-\u3eIR (b=0.18, p=0.001), and IR-\u3eLS (b=0.27, p=0.001)]. Conclusion: Our findings suggest the adipose tissue measured as AO or BMI showed different phenotypic effects on liver fat infiltration or stiffness. Visceral fat had a direct effect on IR, meanwhile, subcutaneous adipose tissue was associated with liver stiffness. Our findings suggest that early age interventions should be focused on reducing visceral fat deposition

Asociación entre consumo de alcohol y exceso de peso entre estudiantes universitarios de América Latina

Introducción: El sobrepeso y la obesidad son problemas de salud pública de nivel mundial. Si bien existe información respecto al consumo de alcohol en estudiantes universitarios durante la pandemia, pocos autores han señalado la asociación entre este hábito y el exceso de peso en esta población. El objetivo fue determinar la asociación entre el consumo de alcohol y el exceso de peso en estudiantes universitarios de 10 países de Latinoamérica durante la pandemia por COVID-19. Metodología: Se realizó un estudio transversal y multicéntrico con 4.539 estudiantes universitarios matriculados en diez países de América Latina. Para la valoración del consumo de alcohol se utilizó la pregunta ¿Consumes bebidas alcohólicas? (1 porción 1 vaso de 200 ml). El índice de masa corporal (IMC) se determinó a partir del peso y la altura auto informado. Para determinar si el exceso de peso (IMC ≥25 kg/m2 ) estaba asociado con el consumo de alcohol, se utilizó un análisis de regresión logística, ajustado por edad, sexo, año de estudio, nivel socioeconómico, actividad física y tabaquismo. Resultados: Entre los estudiantes con estado nutricional normal, un 59,6% no consumía alcohol, mientras entre los que presentaban un exceso de peso era un 55,1%. Los estudiantes que consumían 2 o más porciones de alcohol al día tenían 2,18 veces más riesgo de tener exceso de peso (OR: 2.18 [95% IC: 1,26 a 3,77]), comparado con aquellos que no consumían alcohol. Conclusión: Se observó que aquellos estudiantes que consumieron más alcohol tuvieron más probabilidades de tener exceso de peso. Palabras clave: Alcohol; Índice de masa corporal; Obesidad; Sobrepeso; Universitarios

Congenital leptin deficiency and leptin gene missense mutation found in two colombian sisters with severe obesity

Background: Congenital leptin deficiency is a recessive genetic disorder associated with severe early-onset obesity. It is caused by mutations in the leptin (LEP) gene, which encodes the protein product leptin. These mutations may cause nonsense-mediated mRNA decay, defective secretion or the phenomenon of biologically inactive leptin, but typically lead to an absence of circulating leptin, resulting in a rare type of monogenic extreme obesity with intense hyperphagia, and serious metabolic abnormalities. Methods: We present two severely obese sisters from Colombia, members of the same lineal consanguinity. Their serum leptin was measured by MicroELISA. DNA sequencing was performed on MiSeq equipment (Illumina) of a next-generation sequencing (NGS) panel involving genes related to severe obesity, including LEP. Results: Direct sequencing of the coding region of LEP gene in the sisters revealed a novel homozygous missense mutation in exon 3 [NM_002303.3], C350G>T [p.C117F]. Detailed information and clinical measurements of these sisters were also collected. Their serum leptin levels were undetectable despite their markedly elevated fat mass. Conclusions: The mutation of LEP, absence of detectable leptin, and the severe obesity found in these sisters provide the first evidence of monogenic leptin deficiency reported in the continents of North and South America. © 2019 by the authors. Licensee MDPI, Basel, Switzerland

Randomized Clinical Trials of obesity treatments in Mexican population. Systematic Review and Meta-Analysis

Background: Mexicans and Mexican Americans share similar culture, genetic background, and predisposition for obesity and diabetes. Randomized clinical trials (RCT) assessing obesity treatments (ObT) are reliable to assess efficacy. To date, there is no systematic review to investigate ObT tested by RCT in Mexican adults. Methods: We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve ObT RCT from 1990 to 2019. The ObT included alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions. The analyzed RCT were at least three months of duration, and reported: BMI, weight, waist circumference, triglycerides, glucose and blood pressure. Results: We found 634 entries; after removal of duplicates and exclusions based on eligibility criteria, we analyzed 43 and 2 multinational-collaborative studies. Most of the national studies had small sample sizes, and did not have replications from other studies. The nutrition/behavioral interventions were difficult to blind, and most studies had medium to high risk of bias. Random effects meta-analysis of nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like plain water instead of sweet beverages decreased triglycerides and systolic blood pressure. Participants with obesity and hypertension had beneficial effects with antioxidants, and the treatment with insulin increased weight in those with T2D. Conclusions: The RCT’s in Mexico reported effects on metabolic components despite small sample sizes and lack of replication. In the future we should analyze ObT in population living on the U.S.-Mexico border; therefore, bi-national collaboration is desirable to disentangle cultural effects on ObT response

Looking for Crumbs in the Obesity Forest: Anti-obesity Interventions and Obesity-Associated Cardiometabolic Traits in the Mexican Population. History and Systematic Review With Meta-Analyses

Mexicans and Mexican Americans share culture, genetic background, and predisposition for chronic complications associated with obesity and diabetes making imperative efficacious treatments and prevention. Obesity has been treated for centuries focused-on weight loss while other treatments on associated conditions like gout, diabetes (T2D), and hypertriglyceridemia. To date, there is no systematic review that synthesizes the origin of obesity clinics in Mexico and the efforts to investigate treatments for obesity tested by randomized clinical trials (RCT). We conducted systematic searches in Pubmed, Scopus, and Web of Science to retrieve anti-obesity RCT through 2019 and without an inferior temporal limit. The systematic review included RCT of anti-obesity treatments in the Mexican adult population, covering alternative medicine, pharmacological, nutritional, behavioral, and surgical interventions reporting metabolism-associated traits such as BMI, weight, waist circumference, triglycerides, glucose, among others. Only the studies with at least 3 months of treatment were included in the meta-analyses in order to reduce placebo effects. We found 634 entries, after removal of duplicates and screening the studies based on eligibility criteria, we analyzed 43 national, and 2 multinational-collaborative studies. Most of the national studies had small sample sizes, and the implemented strategies do not have replications in the population. The nutrition/behavioral interventions were difficult to blind, and most studies have medium-to-high risk of bias. Nutritional/behavioral interventions and medications showed effects on BMI, waist circumference, and blood pressure. Simple measures like pure water instead of sweet beverages decrease triglycerides and systolic blood pressure. Dark chocolate showed the highest effect for BMI and high blood pressure, and treatment with insulin increased weight in those with T2D. The study of obesity in Mexico has been on-going for more than four decades, the interest on RCT just increased until this millennium, but with small sample sizes and lack of replication. The interventions affect different cardiometabolic associated traits, which should be analyzed in detail in the population living near the Mexico-U.S. border; therefore, bi-national collaboration is desirable to disentangle the cultural effects on this population\u27s treatment response

Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic low-grade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

Congenital leptin deficiency and leptin gene missense mutation found in two colombian sisters with severe obesity

Background: Congenital leptin deficiency is a recessive genetic disorder associated with severe early-onset obesity. It is caused by mutations in the leptin (LEP) gene, which encodes the protein product leptin. These mutations may cause nonsense-mediated mRNA decay, defective secretion or the phenomenon of biologically inactive leptin, but typically lead to an absence of circulating leptin, resulting in a rare type of monogenic extreme obesity with intense hyperphagia, and serious metabolic abnormalities. Methods: We present two severely obese sisters from Colombia, members of the same lineal consanguinity. Their serum leptin was measured by MicroELISA. DNA sequencing was performed on MiSeq equipment (Illumina) of a next-generation sequencing (NGS) panel involving genes related to severe obesity, including LEP. Results: Direct sequencing of the coding region of LEP gene in the sisters revealed a novel homozygous missense mutation in exon 3 [NM_002303.3], C350G>T [p.C117F]. Detailed information and clinical measurements of these sisters were also collected. Their serum leptin levels were undetectable despite their markedly elevated fat mass. Conclusions: The mutation of LEP, absence of detectable leptin, and the severe obesity found in these sisters provide the first evidence of monogenic leptin deficiency reported in the continents of North and South America. © 2019 by the authors. Licensee MDPI, Basel, Switzerland