Body mass index, systemic inflammation and cognitive performance in adolescents: A cross-sectional study.

BACKGROUND: Excessive body weight has been related to lower cognitive performance. One of the mechanisms through which excess body weight may affect cognition is inflammation. HYPOTHESIS: Our hypothesis is that both body mass index (BMI) and circulating levels of inflammatory biomarkers will be negatively related to cognitive performance. DESIGN: Cross-sectional study. SETTING: Users of the public health centres of the Consorci Sanitari de Terrassa (Terrassa, Spain) between 2010 and 2017 aged 12-21 years. PARTICIPANTS: One hundred and five adolescents (46 normoweight, 18 overweight, 41 obese). MEASUREMENTS: Levels of high sensitivity C-reactive protein, interleukin 6, tumour necrosis factor α (TNFα) and fibrinogen were determined from blood samples. Cognitive performance was evaluated and six cognitive composites were obtained: working memory, cognitive flexibility, inhibitory control, decision-making, verbal memory, and fine motor speed. A single multivariate general lineal model was used to assess the influence of the four inflammatory biomarkers, as well as participants' BMI, sex, and age on the 6 cognitive indexes. RESULTS: An inverse relationship between BMI and inhibitory control (F = 5.688, p = .019; ß = -0.212, p = .031), verbal memory (F = 5.404, p = .022; ß = -0.255, p = .009) and fine motor speed (F = 9.038, p = .003; ß = -0.319, p = .001) was observed. Levels of TNFα and fibrinogen were inversely related to inhibitory control (F = 5.055, p = .027; ß = -0.226, p = .021) and verbal memory (F = 4.732, p = .032; ß = -0.274, p = .005), respectively. LIMITATIONS: The cross-sectional nature of the study, the use of cognitive tests designed for clinical purposes, and the use of BMI as a proxy for adiposity are limitations of our study that must be taken into account when interpreting results. CONCLUSIONS: Our data indicate that some components of executive functions, together with verbal memory, are sensitive to specific obesity-related inflammatory agents at early ages.

Assessing adipokines as potential biomarkers of dementia, Alzheimer's disease, and mild cognitive impairment: A systematic review and meta-analysis.

Midlife obesity and late-life weight loss confer a greater risk for developing dementia and Alzheimer's disease (AD), but the exact mechanisms behind this phenomenon are currently unknown. The answer could lie on the involvement of gastrointestinal factors, such as adipokines (e.g., leptin, adiponectin, and resistin) and ghrelin. In this context, we conducted a pre-registered systematic review and meta-analysis of 42 cross-sectional and 13 longitudinal studies targeting the associations between leptin, adiponectin, resistin, and ghrelin and the prevalence of general dementia, AD, and mild cognitive impairment (MCI). We also examined the relationship between the four gastrointestinal factors and neurocognitive outcomes and AD-related cerebrospinal fluid biomarkers. Patients with AD had lower blood leptin and higher resistin levels than cognitively normal participants. Lower leptin and higher resistin were associated with higher degree of cognitive impairment. Additionally, lower late-life leptin levels might be associated with higher prospective risk of dementia and AD, although more studies are needed to corroborate this. Results in ghrelin and adiponectin were not conclusive, with age, sex distribution, obesity, and severity of dementia seemingly acting as moderators across several analyses. Our work might contribute to the identification of new preclinical blood markers of MCI and AD.

Neuroanatomical changes in white and grey matter after sleeve gastrectomy.

BACKGROUND: MRI studies show that obese adults have reduced grey matter (GM) and white matter (WM) tissue density as well as altered WM integrity. Bariatric surgery can lead to substantial weight loss and improvements in metabolic parameters, but it remains to be examined if it induces structural brain changes. The aim of this study was to characterize GM and WM density changes measured with MRI in a longitudinal setting following sleeve gastrectomy, and to determine whether any changes are related to inflammation and cardiometabolic blood markers. METHODS: 29 participants with obesity (age: 45.9 â€‹± â€‹7.8 years) scheduled to undergo sleeve gastrectomy were recruited. High-resolution T1-weighted anatomical images were acquired 1 month prior to as well as 4 and 12 months after surgery. GM and WM densities were quantified using voxel-based morphometry (VBM). Circulating lipid profile, glucose, insulin and inflammatory markers (interleukin-6, C-reactive protein and lipopolysaccharide-binding protein) were measured at each time point. A linear mixed effect model was used to compare brain changes before and after SG, controlling for age, sex, initial BMI and diabetic status. To assess the associations between changes in adiposity, metabolism and inflammation and changes in GM or WM density, the mean GM and WM densities were extracted across all the participants using atlas-derived regions of interest, and linear mixed-effect models were used. RESULTS: As expected, weight, BMI, waist circumference and neck circumference significantly decreased after SG compared with baseline (p â€‹< â€‹0.001 for all). A widespread increase in WM density was observed after surgery, particularly in the cerebellum, brain stem, cerebellar peduncle, cingulum, corpus callosum and corona radiata (p â€‹< â€‹0.05, after FDR correction). Significant increases in GM density were observed 4 months after SG compared to baseline in several brain regions such as the bilateral occipital cortex, temporal cortex, postcentral gyrus, cerebellum, hippocampus and insula as well as right fusiform gyrus, right parahippocampal gyrus, right lingual gyrus and right amygdala. These GM and WM increases were more pronounced and widespread after 12 months and were significantly associated with post-operative weight loss and the improvement of metabolic alterations. A linear mixed-effect model also showed associations between post-operative reductions in lipopolysaccharide-binding protein, a marker of inflammation, and increased WM density. To confirm our results, we tested whether the peak of each significant region showed BMI-related differences in an independent dataset (Human Connectome Project). We matched a group of individuals who were severely obese with a group of individuals who were lean for age, sex and ethnicity. Severe obesity was associated with reduced WM density in the brain stem and cerebellar peduncle as well as reduced GM density in cerebellum, regions that significantly changed after surgery (p â€‹< â€‹0.01 for all clusters). CONCLUSIONS: Bariatric surgery-induced weight loss and improvement in metabolic alterations is associated with widespread increases in WM and GM densities. These post-operative changes overlapped with baseline brain differences between participants who were severely obese and those who were normal-weight in a separate dataset, which may suggest a recovery of WM and GM alterations after bariatric surgery.

Uncontrolled eating: a unifying heritable trait linked with obesity, overeating, personality and the brain.

Many eating-related psychological constructs have been proposed to explain obesity and overeating. However, these constructs, including food addiction, disinhibition, hedonic hunger, emotional eating, binge eating and the like all have similar definitions, emphasizing loss of control over intake. As questionnaires measuring the constructs correlate strongly (r > 0.5) with each other, we propose that these constructs should be reconsidered to be part of a single broad phenotype: uncontrolled eating. Such an approach enables reviewing and meta-analysing evidence obtained with each individual questionnaire. Here, we describe robust associations between uncontrolled eating, body mass index (BMI), food intake, personality traits and brain systems. Reviewing cross-sectional and longitudinal data, we show that uncontrolled eating is phenotypically and genetically intertwined with BMI and food intake. We also review evidence on how three psychological constructs are linked with uncontrolled eating: lower cognitive control, higher negative affect and a curvilinear association with reward sensitivity. Uncontrolled eating mediates all three constructs' associations with BMI and food intake. Finally, we review and meta-analyse brain systems possibly subserving uncontrolled eating: namely, (i) the dopamine mesolimbic circuit associated with reward sensitivity, (ii) frontal cognitive networks sustaining dietary self-control and (iii) the hypothalamus-pituitary-adrenal axis, amygdala and hippocampus supporting stress reactivity. While there are limits to the explanatory and predictive power of the uncontrolled eating phenotype, we conclude that treating different eating-related constructs as a single concept, uncontrolled eating, enables drawing robust conclusions on the relationship between food intake and BMI, psychological variables and brain structure and function.

Brain Functional Connectivity Is Modified by a Hypocaloric Mediterranean Diet and Physical Activity in Obese Women.

Functional magnetic resonance imaging (fMRI) in the resting state has shown altered brain connectivity networks in obese individuals. However, the impact of a Mediterranean diet on cerebral connectivity in obese patients when losing weight has not been previously explored. The aim of this study was to examine the connectivity between brain structures before and six months after following a hypocaloric Mediterranean diet and physical activity program in a group of sixteen obese women aged 46.31 ± 4.07 years. Before and after the intervention program, the body mass index (BMI) (kg/m²) was 38.15 ± 4.7 vs. 34.18 ± 4.5 (p < 0.02), and body weight (kg) was 98.5 ± 13.1 vs. 88.28 ± 12.2 (p < 0.03). All subjects underwent a pre- and post-intervention fMRI under fasting conditions. Functional connectivity was assessed using seed-based correlations. After the intervention, we found decreased connectivity between the left inferior parietal cortex and the right temporal cortex (p < 0.001), left posterior cingulate (p < 0.001), and right posterior cingulate (p < 0.03); decreased connectivity between the left superior frontal gyrus and the right temporal cortex (p < 0.01); decreased connectivity between the prefrontal cortex and the somatosensory cortex (p < 0.025); and decreased connectivity between the left and right posterior cingulate (p < 0.04). Results were considered significant at a voxel-wise threshold of p ≤ 0.05, and a cluster-level family-wise error correction for multiple comparisons of p ≤ 0.05. In conclusion, functional connectivity between brain structures involved in the pathophysiology of obesity (the inferior parietal lobe, posterior cingulate, temporo-insular cortex, prefrontal cortex) may be modified by a weight loss program including a Mediterranean diet and physical exercise.

Capacidad antioxidante total en alimentos convencionales y regionales de Chiapas, México / Total antioxidant capability of conventional and regional foods in Chiapas, Mexico

OBJETVIO: evaluar la capacidad antioxidante total de 24 alimentos convencionales y nueve propios de la región del Estado de Chiapas. MÉTODOS: los alimentos fueron recolectados en el Mercado "Rafael Pascacio Gamboa" de Tuxtla Gutiérrez:17 pertenecientes al grupo de vegetales o verduras, siete al grupo de frutas y nueve considerados regionales. Para determinar la capacidad antioxidante total se empleó la técnica de Miller y otros que se basa en la formación de un radical de coloración verde azulada que se mide a 600 nm. Esta coloración es proporcional a la actividad antioxidante y se mide por comparación con un patrón que es un derivado sintético de la vitamina E. RESULTADOS: los mayores valores de capacidad antioxidante se encontró en la calabacita cocida y los menores en el pepino; otros vegetales como el aguacate, berro, lechuga y cebolla, tenían valores superiores a los encontrados en estas especies cultivadas en Cuba. En las frutas, sucedió al revés, correspondieron los mayores valores a la guayaba, naranja y papaya cultivada en Cuba. Los alimentos regionales mejores por su capacidad antioxidante resultaron ser la verdolaga y la yerba buena. CONCLUSIONES: con los resultados alcanzados se espera contribuir a diseminar la importancia de ingerir aquellos alimentos que por su capacidad antioxidante protegen al organismo de la acción de los radicales libres, causantes de los procesos de envejecimiento y de algunas enfermedades.

OBJECTIVES: To evaluate the total antioxidant capability of 24 conventional foods and nine regional foods from Chiapas state. METHODS: The foods were picked up at "Rafael Pascacio Gamboa" marketplace of Tuxtla Gutiérrez: 17 foods from the vegetable or greenery group, seven from the fruit group and nine that were considered regional. To determine the total antioxidant capability, we used Miller et al's technique that is based on the formation of a green-blue coloured radical measured at 600nm. This colouring is proportional to antioxidant activity and is measured by comparing it to a vitamin E-synthetic derivative pattern. RESULTS: Among the regional vegetables, it was found that boiled courgettes exhibited the highest antioxidant capability values whereas cucumber had the lowest; on the other hand, vegetables like avocato pear, watercress, cabbage and onion demonstrated higher antioxidant values than those of the same species grown in Cuba. On the contrary, guava, orange and papaya grown in Cuba had the highest antioxidant figures in the fruit group. The best regional foods as to the antioxidant capability were mint and purslane. CONCLUSIONS: It is hoped that the achieved results will contribute to underline the importance of eating those foods whose antioxidant capability protect the body from the action of free radicals causing aging and some diseases.

Características antropométricas, capacidad antioxidante y perfil lipídico sanguíneo de un grupo de mujeres hipertensas de la ciudad de Tuxtla Gutiérrez. Chiapas. México / Anthropometrics characteristics, antioxidant status and lipid seric in hypertension women’s group from Tuxtla Gutierrez city. Chiapas. México

La hipertensión y las dislipidemias son factores de riesgos cardiovasculares que presentan una alta incidencia en México. En el presente trabajo se reportan los datos de un estudio descriptivo de las principales características antropométricas, del perfil lipídico y capacidad antioxidante sanguínea, de un grupo de mujeres hipertensas de la ciudad de Tuxtla Gutiérrez. Para ello se realizaron determinaciones de indicadores antropométricos, de perfil lipídico y capacidad antioxidante total del suero de un grupo de 37 pacientes hipertensas del Hospital Regional de la ciudad de Tuxtla Gutiérrez en Chiapas. México. En el grupo poblacional, el 76 porciento de las pacientes cumplieron con los valores de referencia para el colesterol total y el transportado por las HDL y LDL, pero más de la mitad de ellas presentaron hipertrigliceridemia. Sus capacidades antioxidantes sanguíneas se caracterizaron por valores ligeramente más bajos que los establecidos como referencia para la población europea. En el grupo también se presentaron otros factores de riesgos como la edad y la relación cintura/cadera.