Leptin-reactive antibodies are distinctly correlated with body composition parameters and metabolic risk indexes in children and adolescents.

Studies have demonstrated the presence of low-affinity immunoglobulins (Igs) directed to leptin, a key hormone of the neuroendocrine axis that regulates appetite and metabolism, in adult healthy subjects, patients with obesity, and type 2 diabetes mellitus. In the present exploratory study, IgG leptin-reactive antibodies were analyzed for the first time in children and adolescents according to body mass index (BMI) and were correlated with biochemical profile (lipid profile, insulin, glucose, and leptin) and metabolic risk indexes [homeostasis model assessment for insulin resistance (HOMA-IR), homeostasis model assessment for ß-cell function (HOMA-ß), atherogenic index of plasma (AIP)]. One hundred and thirty-six participants were included (children n = 63, adolescents n = 73). An in-house enzyme-linked immunosorbent assay (ELISA) test was performed to measure IgG anti-leptin antibodies (free, total, and immune complexes). In adolescents, free and total IgG anti-leptin antibodies levels were higher in groups with overweight or obesity than in normal-weight group (P < 0.01), while in children, the total fractions were lower in groups with overweight and obesity than in normal weight (P < 0.02). Immune complexes percentage showed opposite correlations with BMI in children (r = 0.4004, P = 0.0473) and adolescents (r = -0.3983, P = 0.0133). IgG anti-leptin antibodies were also correlated with HOMA-IR in children (r = -0.4569, P = 0.0217) and adolescents (r = -0.3589, P = 0.0316), and with AIP (r = -0.3608, P = 0.0261) in adolescents. Our data suggest that the production and affinity of IgG anti-leptin antibodies can be affected by age, body composition, and metabolic conditions; additionally, in normal conditions, IgG anti-leptin antibodies may have a protective role in insulin resistance and cardiovascular events.

CD36 gene polymorphism -31118 G > A (rs1761667) is associated with overweight and obesity but not with fat preferences in Mexican children.

CD36 glycoprotein is a candidate receptor involved in the gustatory detection of lipids and emerging evidence has suggested that genetic variations in CD36 may modulate the oral perception threshold to fatty acids. Here, we analyzed the association of -31118 G > A polymorphism in CD36 gene with nutritional status and preferences for fatty foods in Mexican children. Genotyping of SNP rs1761667 was performed in school-age children (n = 63) in addition to sensory tests evaluating the preference and satisfaction score assigned to oil-based sauces of different fatty acid composition. The G allele was associated with high BMI z-score in children (OR = 2.43, 95% (CI 1.02-5.99); p = 0.02) but CD36 genotypes (AA, GA, and GG) did not show significant association with the preference and satisfaction scores assigned to oil-based sauces. The BMI z-score showed no association with the preference to oil-based sauces; however, children with normal weight gave higher satisfaction scores to sauces with a high content of unsaturated fatty acids than to sauces rich in saturated fatty acids (0.56 ± 1.26 vs. 0.06 ± 1.22; p = 0.02). Therefore, the G allele of -31118 G > A SNP in CD36 gene is associated with overweight and obesity in Mexican children but do not appear to modulate the preferences and satisfaction scores to fat.

Leptin/Ghrelin Axis and Antibodies Reactive to Both Hormones in Relation to Metabolic Syndrome Components in Mexican Children.

Background: Metabolic syndrome (MetS) in children is a rising health issue that is strongly associated with cardiovascular diseases and type 2 diabetes mellitus development. Low-affinity antibodies reactive to leptin and ghrelin are suggested to regulate hormone stability and function; nevertheless, the role of the leptin/ghrelin axis and antibodies reactive to both hormones in relation to MetS or its components in the pediatric population remains unknown. Methods: Fifty-eight children (7-12 years) were included and categorized according to the presence of one or more criteria for the diagnosis of MetS or according to body mass index. Body composition, biochemical variables, and metabolic risk indexes were determined. Antibodies reactive to leptin and ghrelin were quantified by an in-house enzyme-linked immunosorbent assay test. Ratios of leptin/ghrelin hormones and anti-leptin/anti-ghrelin immune complexes were obtained. Results: The biochemical variables glucose (P = 0.0009), insulin (P = 0.0001), leptin (P = 0.0036), HOMA-IR (homeostatic model assessment for insulin resistance) (P < 0.0001), and plasma atherogenic index (P < 0.0001) were significantly higher in children with two or three components of MetS (MetS 2-3) in comparison to children with none or one component (MetS 0-1). Ratios of leptin/ghrelin (P = 0.0307) and anti-leptin/anti-ghrelin immune complexes (P = 0.0338) were higher in MetS 2-3 group versus MetS 0-1 group. In MetS 2-3 group, both insulin (r = 0.4361, P = 0.0293) and HOMA-IR (r = 0.4761, P = 0.0161) were positively correlated with the leptin/ghrelin hormone ratio. Conclusions: The higher leptin/ghrelin hormone ratio scores observed in MetS 2-3 group, along with their correlation with insulin levels and HOMA-IR, highlight the role of leptin and ghrelin on insulin sensitivity and metabolic regulation. An increased ratio of anti-leptin/anti-ghrelin immune complexes suggests affinity changes in these antibodies that may lead to alterations in hormone function.

[Genetic variants in CD36: emerging role in oral fat perception and food preferences]. / Variantes genéticas en CD36: evidencia emergente en la percepción oral de las grasas y las preferencias alimentarias.

Introduction: CD36 is a receptor involved in physiologic, metabolic and pathologic processes. Due to its affinity for long-chain fatty acids, it has been postulated as a taste receptor of fatty taste. In this review, the emerging genetic evidence linking CD36 to oral fat perception is analyzed. A systematic literature search was conducted in PubMed, published articles from 2000 to 2022 were considered. Multiple studies have shown an association of some genetic variants in CD36 with fat foods preferences and it has been suggested that these variants can modify oral fat perception thresholds however the evidence is still heterogeneous; this can be explained by the genetic diversity of populations, the nutritional status and participant's characteristics, as well as other methodological aspects. Other factors involved in oral fat perception were and identified and discussed including the interaction with other flavors, hormones, and epigenetic factors. The conclusion is that the evidence supporting the role of CD36 as a dietary lipid receptor, the role of its genetic variants in fat acids oral perception thresholds and food preferences is intermediate level and more investigations are necessary in other populations with large number of participants as well as considering the interaction between different hormones and the expression of CD36.

Introducción: CD36 es un receptor involucrado en procesos fisiológicos, metabólicos y patológicos. Debido a su afinidad por ácidos grasos de cadena larga es uno de los principales receptores de lípidos provenientes de la dieta. En esta revisión se analiza la evidencia genética emergente que vincula a CD36 en la percepción oral de grasa. Se realizó una búsqueda sistemática en la base de datos PubMed considerando artículos publicados en el periodo 2000-2022. Múltiples estudios asocian a algunas variantes genéticas en CD36 con las preferencias por alimentos con contenido graso y se ha postulado que estas variantes pueden modificar los umbrales de percepción oral de grasas, sin embargo, la evidencia es heterogénea; esto puede ser explicado por la diversidad genética de las poblaciones, el estado nutricional y características de los participantes, así como a otros aspectos metodológicos. Se identificaron y se discuten otros factores implicados en la percepción oral de grasas, incluyendo la interacción con otros sabores, hormonas y factores epigenéticos. Se concluye que la evidencia que apoya el papel de CD36 como receptor de los lípidos provenientes de la dieta es intermedio y son necesarias más investigaciones en diversas poblaciones con un gran número de participantes, así como considerar la interacción entre distintas hormonas y la expresión de CD36.

Variantes genéticas en CD36: evidencia emergente en la percepción oral de las grasas y las preferencias alimentarias / Genetic variants in CD36: emerging role in oral fat perception and food preferences

CD36 es un receptor involucrado en procesos fisiológicos, metabólicos y patológicos. Debido a su afinidad por ácidos grasos de cadena larga es uno de los principales receptores de lípidos provenientes de la dieta. En esta revisión se analiza la evidencia genética emergente que vincula a CD36 en la percepción oral de grasa. Se realizó una búsqueda sistemática en la base de datos PubMed considerando artículos publicados en el periodo 2000-2022. Múltiples estudios asocian a algunas variantes genéticas en CD36 con las preferencias por alimentos con contenido graso y se ha postulado que estas variantes pueden modificar los umbrales de percepción oral de grasas, sin embargo, la evidencia es heterogénea; esto puede ser explicado por la diversidad genética de las poblaciones, el estado nutricional y características de los participantes, así como a otros aspectos metodológicos. Se identificaron y se discuten otros factores implicados en la percepción oral de grasas, incluyendo la interacción con otros sabores, hormonas y factores epigenéticos. Se concluye que la evidencia que apoya el papel de CD36 como receptor de los lípidos provenientes de la dieta es intermedio y son necesarias más investigaciones en diversas poblaciones con un gran número de participantes, así como considerar la interacción entre distintas hormonas y la expresión de CD36. (AU)

CD36 is a receptor involved in physiologic, metabolic and pathologic processes. Due to its affinity for long-chain fatty acids, it has been postulated as a taste receptor of fatty taste. In this review, the emerging genetic evidence linking CD36 to oral fat perception is analyzed. A systematic literature search was conducted in PubMed, published articles from 2000 to 2022 were considered. Multiple studies have shown an association of some genetic variants in CD36 with fat foods preferences and it has been suggested that these variants can modify oral fat perception thresholds however the evidence is still heterogeneous; this can be explained by the genetic diversity of populations, the nutritional status and participant’s characteristics, as well as other methodological aspects. Other factors involved in oral fat perception were and identified and discussed including the interaction with other flavors, hormones, and epigenetic factors. The conclusion is that the evidence supporting the role of CD36 as a dietary lipid receptor, the role of its genetic variants in fat acids oral perception thresholds and food preferences is intermediate level and more research is necessary in other populations with large number of participants as well as considering the interaction between different hormones and the expression of CD36. (AU)

Obesidad, ingesta energética y comportamiento alimentario: Una revisión de los principales factores involucrados / Obesity, energy intake and eating behavior: A review of the main factors involved

Resumen La obesidad constituye un problema de salud a nivel mundial y una de las principales causas de las enfermedades crónicas. Existen diversos factores que influyen en el comportamiento alimentario y la obesidad, los cuales pueden ser genéticos, fisiológicos, nutricionales, psicológicos o socioculturales. En las últimas décadas, el cambio en el estilo de vida ha provocado patrones de alimentación inadecuados, aunados a disminución en el gasto energético. En esta revisión se describen los principales factores fisiológicos, nutricionales y psicológicos que intervienen en la ingesta energética y el comportamiento alimentario, y cómo es que estos pueden −vía la regulación del apetito y del peso corporal− influir en el desarrollo de la obesidad. La neuropsicología de la recompensa de los alimentos, de las preferencias, de la elección y del comportamiento alimentario son aspectos aún no comprendidos. Investigaciones futuras tienen que enfocarse en dilucidar las vías involucradas en los aspectos gratificantes de los alimentos y, como una alternativa para controlar la obesidad, replicar esta experiencia con alimentos más saludables. Sin embargo, la comprensión del vínculo entre alimentación, ingesta energética y regulación del peso corporal solo se logrará a través del trabajo multidisciplinario.

Abstract Obesity is a global health problem and one of the main causes of chronic diseases. There are several factors that influence eating behavior and obesity, which can be genetic, physiological, nutritional, psychological or sociocultural. In recent decades, the change in lifestyle has caused inadequate eating patterns, coupled with a decrease in energy expenditure. This review describes the main physiological, nutritional and psychological factors that intervene in energy intake and eating behavior and how they can -by regulating appetite and body weight- influence the development of obesity. The neuropsychology of food reward, preferences, choice and eating behavior are aspects not yet understood. Future research needs to focus on elucidating the pathways involved in the rewarding aspects of food and, as an alternative to control obesity, replicate this experience with healthier foods. However, understanding the link between food, energy intake and body weight regulation will only be achieved through multidisciplinary work.