Therapeutic actions of tea phenolic compounds against oxidative stress and inflammation as central mediators in the development and progression of health problems: A review focusing on microRNA regulation

Many health problems including chronic diseases are closely associated with oxidative stress and inflammation. Tea has abundant phenolic compounds with various health benefits including antioxidant and anti-inflammatory properties. This review focuses on the present understanding of the impact of tea phenolic compounds on the expression of miRNAs, and elucidates the biochemical and molecular mechanisms underlying the transcriptional and post-transcriptional protective actions of tea phenolic compounds against oxidative stress- and/or inflammation-mediated diseases. Clinical studies showed that drinking tea or taking catechin supplement on a daily basis promoted the endogenous antioxidant defense system of the body while inhibiting inflammatory factors. The regulation of chronic diseases based on epigenetic mechanisms, and the epigenetic-based therapies involving different tea phenolic compounds, have been insufficiently studied. The molecular mechanisms and application strategies of miR-27 and miR-34 involved in oxidative stress response and miR-126 and miR-146 involved in inflammation process were preliminarily investigated. Some emerging evidence suggests that tea phenolic compounds may promote epigenetic changes, involving non-coding RNA regulation, DNA methylation, histone modification, ubiquitin and SUMO modifications. However, epigenetic mechanisms and epigenetic-based disease therapies involving phenolic compounds from different teas, and the potential cross-talks among the epigenetic events, remain understudied.

Low-Grade Inflammation and Role of Anti-Inflammatory Diet in Childhood Obesity

At present, pediatric obesity is a significant public health concern. We have seen a surge of disorders that are obesity-related, e.g., insulin resistance (IR), type 2 diabetes mellitus (T2DM), high blood pressure, heart disease, stroke, cancer, non-alcoholic fatty liver disease (NAFLD), autoimmune disorders and many more. The mechanisms linking these diseases to excess body weight are related to low-grade inflammation (LGI). Although there is a limited number of studies assessing this immune process in childhood obesity, they indicate its significant importance for the health of future generations. There is a need for more research into the prevention and treatment of low-grade inflammation in childhood. The aim of this review is to present and discuss the process of "cold" inflammation, and its impact on health and anti-inflammation nutrition. A diet rich in anti-inflammatory nutrients may be the key to maintaining health, as well as recovery.

Causative Mechanisms of Childhood and Adolescent Obesity Leading to Adult Cardiometabolic Disease: A Literature Review

The past few decades have shown a worrisome increase in the prevalence of obesity and its related illnesses. This increasing burden has a noteworthy impact on overall worldwide mortality and morbidity, with significant economic implications as well. The same trend is apparent regarding pediatric obesity. This is a particularly concerning aspect when considering the well-established link between cardiovascular disease and obesity, and the fact that childhood obesity frequently leads to adult obesity. Moreover, most obese adults have a history of excess weight starting in childhood. In addition, given the cumulative character of both time and severity of exposure to obesity as a risk factor for associated diseases, the repercussions of obesity prevalence and related morbidity could be exponential in time. The purpose of this review is to outline key aspects regarding the current knowledge on childhood and adolescent obesity as a cardiometabolic risk factor, as well as the most common etiological pathways involved in the development of weight excess and associated cardiovascular and metabolic diseases.

Change in obesity-related metabolic abnormalities associated with body mass index improvement through life-style intervention: A meta-regression

The reduction in body mass index standard deviation score (BMI-SDS) associated with improvement in biomarkers relating to metabolic health in obese children is unknown. We aimed to establish the change in BMI-SDS associated with improved inflammation, liver function, and insulin resistance to inform clinical guidelines for pediatric weight management interventions and to assess the efficacy of future trials. A large-scale systematic review was conducted to identify relevant studies. Studies of children with a diagnosis of obesity according to defined BMI thresholds, participating in lifestyle interventions to reduce obesity, were included. Studies must have reported baseline (pre-) and postintervention (or change of) BMI-SDS and either fasting glucose, homeostatic model of insulin resistance (HOMA-IR), alanine aminotransferase (ALT), C-reactive protein (CRP), or interleukin-6 (IL-6). A series of meta-regressions were conducted to establish links between BMI-SDS change scores and change in metabolic markers of health. Sixty-eight articles were identified. From the meta-regression analyses, across all study subsets, greater mean falls in all four parameters, (HOMA-IR, Glucose, ALT, and CRP) were observed with greater mean loss of BMI-SDS, but the trends were only statistically significant for HOMA-IR and CRP (P = .003; P = .021). However, we could not find minimum changes in BMI-SDS that would ensure a fall in these outcomes. At this time, we are unable to recommend a definitive value of BMI-SDS reduction needed to improve the markers of metabolic health. Future trials should aim to report additional indices of derived BMI values, which may better reflect changes in actual adiposity.

Association between inflammation, oxidative stress, vitamin D, copper and zinc with pre-obesity and obesity in school children from the city of Podgorica, Montenegro

Background Childhood obesity is a serious health condition with increasing rates worldwide. The aim of this study was to investigate the association between inflammation, oxidative stress, vitamin D, copper and zinc in pre-obese and obese children compared to controls. Methods The study involved 202 children aged 7-15 years (63.9% boys), randomly chosen from 10 elementary schools in Podgorica, Montenegro. Participants were divided into three groups according to their nutritional status (International Obesity Task Force [IOTF] criteria): normal-weight (42.1%), pre-obese (40.6%) and obese (17.3%). Serum biochemical analyses were performed (C-reactive protein [CRP], retinol-binding protein [RBP], total antioxidant status [TAS], total vitamin D [VD], copper and zinc). Results Serum TAS and CRP concentrations were higher in pre-obese and obese children compared to controls (p < 0.001). Serum VD concentrations were lower in pre-obese and obese children compared to their normal-weight peers (p = 0.027 and p = 0.054, respectively). Copper, zinc and RBP concentrations did not differ significantly among the groups (p > 0.05). In pre-obese and obese children, a positive correlation was found between CRP and copper (r = 0.305, p = 0.011 and r = 0.440, p = 0.013, respectively), and TAS and RBP (r = 0.528, p < 0.001 and r = 0.434, p = 0.015, respectively). Standard regression analyses showed that CRP and TAS increase (p < 0.001) whereas VD decreases (p = 0.011) with the body mass index (BMI). Conclusions We show that pre-obesity and obesity in childhood are positively associated with oxidative stress and inflammation, and inversely associated with VD status. Copper and zinc concentrations were not associated with excess fat in children.

Ability of Nontraditional Risk Factors and Inflammatory Biomarkers for Cardiovascular Disease to Identify High Cardiometabolic Risk in Adolescents: Results From the LabMed Physical Activity Study

PURPOSE

Then objective of this study was to evaluate the ability of several nontraditional cardiometabolic and inflammatory biomarkers in identifying high cardiometabolic risk in adolescents.

METHODS

A cross-sectional study was conducted with 529 Portuguese adolescents (267 girls) aged 14.3 ± 1.7 years. A clustered cardiometabolic risk score (body fat percentage, systolic blood pressure, ratio of total cholesterol to high-density lipoprotein cholesterol, triglycerides, homeostatic model assessment of insulin resistance, and negative values of cardiorespiratory fitness) was computed. The nontraditional cardiometabolic biomarkers assessed were complement factors (C3 and C4), C-reactive protein (CRP), fibrinogen, leptin, white blood cells (WBCs), albumin, interleukin-6, and a clustered score of inflammatory biomarkers (InflaScore) (C3, C4, CRP, fibrinogen, and leptin).

RESULTS

Receiver operating characteristic curves analyses showed that C3, C4, CRP, fibrinogen, leptin, and the InflaScore were able to present discriminatory ability in identifying an unfavorable cardiometabolic profile in both girls and boys (p <.01 for all). Logistic regression analyses showed that C3, C4, CRP, fibrinogen, leptin, the InflaScore (in both sexes), and WBC (boys) were associated with high cardiometabolic risk, independent of age, pubertal stage, socioeconomic status, or adherence to a Mediterranean diet (p <.05 for all).

CONCLUSIONS

C3, C4, CRP, fibrinogen, and leptin were associated with high cardiometabolic risk in both sexes and WBC in boys. In addition, the clustered inflammatory biomarkers seem to have a better diagnostic accuracy in identifying an unfavorable cardiometabolic profile than single biomarkers. Such biomarkers may have utility in motivating health professionals, public health workers, and adolescents' families toward lifestyle changes, improving prevention efforts early in life.

Association between Leptin, Adiponectin, and Leptin/Adiponectin Ratio with Clustered Metabolic Risk Factors in Portuguese Adolescents: The LabMed Physical Activity Study

Introduction: Circulating leptin and adiponectin levels have been associated with impaired vascular function, insulin resistance, and acute cardiovascular evens. This study aimed to evaluate the associations of leptin, adiponectin, and the leptin/adiponectin (L/A) ratio with a clustering of metabolic risk factors (MRF) in adolescents aged 12-18 years. Methods: This is a cross-sectional analysis with 529 Portuguese adolescents aged 12-18 years. Blood samples were taken to analyze total cholesterol (TC) and high-density lipoprotein (HDL) cholesterol (HDL-c), triglycerides glucose, insulin, leptin, and adiponectin levels. A continuous variable of clustered MRF score (sum of Z-scores of body fat percentage, systolic blood pressure, ratio TC/HDL, triglycerides, homeostatic model assessment insulin resistance, and cardiorespiratory fitness*[-1]) was computed. Results: Regression analyses showed that adiponectin was a significant and negative predictor of MRF score (boys: β = -0.199; p < 0.001; girls: β = -0.200; p < 0.001); whereas leptin was a significant positive predictor of MRF score (boys: β = 0.553; p < 0.001; girls: β = 0.399; p < 0.001). The L/A ratio was also a significant positive predictor of MRF score in both sexes (boys: β = 0.593; p < 0.001; girls: β = 0.461; p < 0.001), after adjustments for age, pubertal stage, adherence to the Mediterranean diet, and socioeconomic status. In addition, adiponectin, leptin, and L/A ratio were accurate to predict MRF among adolescents, but L/A ratio showed the highest area under receiver operating characteristic curve. Conclusion: Leptin, adiponectin, and L/A ratio are associated with the clustering of MRF in adolescents after adjustments for age, sex, pubertal stage, adherence to the Mediterranean diet, and socioeconomic status. L/A ratio was more strongly associated with MRF score than adiponectin or leptin.

Proteína C-reativa, atividade física e aptidão cardiorrespiratória em adolescentes portugueses: um estudo transversal

O objetivo deste estudo foi investigar a associação da atividade física (AF) e aptidão cardiorrespiratória com os níveis de concentração proteína C-reativa (PCR) em adolescentes. Fizeram parte da amostra 386 adolescentes Portugueses (n = 207, feminino), de 12-18 anos avaliados no ano de 2012. AF foi avaliada com acelerômetros e a aptidão cardiorrespiratória pelo teste de Vai- e-vem da bateria de testes fitnessgram. Amostras sanguíneas foram obtidas após jejum de 10 horas e posteriormente avaliaram-se os níveis de concentração de PCR por alta sensibilidade. Foram encontradas associações significativas entre a PCR e a aptidão cardiorrespiratória no gênero feminino (r = -0,313; p < 0.001) e masculino (r = -0,163; p < 0,05), porém quando ajustadas pelo IMC essas associações permaneceram significativas apenas no gênero feminino (r = -0,215; p < 0,001). Para associações entre PCR e AF não se encontraram associações estatisticamente significativas em ambos os gêneros. Assim a PCR aparentemente se associa de forma negativa com a aptidão cardiorrespiratória, mas de forma diferenciada em função do gênero, sendo que no feminino parece menos dependente do IMC.

Clinical Relevance of Transforming Growth Factor-β1, Interleukin-6 and Haptoglobin for Prediction of Obesity Complications in Prepubertal Egyptian Children

BACKGROUND:

The rate of obesity is increasing throughout the world. Obesity in adults’ research is characterized by chronic inflammation, associated with type 2 Diabetes and cardiovascular risk. The degree to which these changes occur in childhood obesity is not fully defined.

AIM:

This study was designed to explore the relation between circulating levels of pro-inflammatory cytokines, and obesity.

PATIENTS AND METHODS:

This cross sectional case control study was carried out in 50 randomly selected pre-pubertal overweight and obese children compared with fifty apparently healthy children of matched age and sex. Serum levels of transforming growth factor-β1, interleukin-6, and haptoglobin were quantified by ELISA technique.

RESULTS:

ANOVA test followed by Post Hoc test showed highly significant increase in the serum levels of the transforming growth factor-β1, interleukin-6 and haptoglobin among obese children compared to overweight and healthy children respectively. The body weight, BMI and BMI z-score were significantly positively correlated with serum levels of the three pro-inflammatory cytokines. Serum levels of interleukin-6, and haptoglobin were found to be strong predictors of complications in severe obesity by linear regression analysis.

CONCLUSIONS:

Obesity is associated with chronic low-grade inflammation. High levels of interleukin-6 and haptoglobin are considered to be early biomarkers of inflammation associated with severe obesity with subsequent cardiovascular and type 2 diabetes risk.