Current review of genetics of human obesity: from molecular mechanisms to an evolutionary perspective

Methanol extract of Elsholtzia fruticosa promotes 3T3-L1 preadipocyte differentiation

Elsholtzia fruticosa (EF) is present in tropical regions throughout South Asian countries as well as the Himalayas. Although it has been used as a traditional medicine to treat digestive, respiratory, and inflammatory issues, its effect on preadipocyte differentiation is unknown. In this study, we examined the effects of a methanol extract prepared from EF on the differentiation of 3T3-L1 preadipocytes. Cell differentiation was assessed by microscopic observation and oil-red O staining. The expression of adipogenic and lipogenic genes, including PPARγ and C/EBPα, was measured by western blot analysis and quantitative real-time polymerase chain reaction (qRT-PCR), to provide insight into adipogenesis and lipogenesis mechanisms. The results indicated that EF promotes the differentiation of 3T3-L1 preadipocytes, with elevated lipid accumulation occurring in a concentration-dependent manner without apparent cytotoxicity. EF enhances the expression of adipogenic and lipogenic genes, including PPARγ, FABP4, adiponectin, and FAS, at the mRNA and protein levels. The effect of EF was more pronounced during the early and middle stages of 3T3-L1 cell differentiation. Treatment with EF decreased C/EBP homologous protein (CHOP) mRNA and protein levels, while increasing C/EBPα and PPARγ expression. Treatment with EF resulted in the upregulation of cyclin E and CDK2 gene expression within 24 h, followed by a decrease at 48 h, demonstrating the early-stage impact of EF. A concomitant increase in cyclin-D1 levels was observed compared with untreated cells, indicating that EF modulates lipogenic and adipogenic genes through intricate mechanisms involving CHOP and cell cycle pathways. In summary, EF induces the differentiation of 3T3-L1 preadipocytes by increasing the expression of adipogenic and lipogenic genes, possibly through CHOP and cell cycle-dependent mechanisms.

HDAC1 inhibits beige adipocyte-mediated thermogenesis through histone crotonylation of Pgc1a/Ucp1

Obesity, one of the most serious public health issues, is caused by the imbalance of energy intake and energy expenditure. Increasing energy expenditure via induction of adipose tissue browning has become an appealing strategy to treat obesity and associated metabolic complications. Although histone modifications have been confirmed to regulate cellular energy metabolism, the involved biochemical mechanism of thermogenesis in adipose tissue is not completely understood. Herein, we report that class I histone deacetylases (HDAC) inhibitor MS275 increased PGC1α/UCP1 protein levels in inguinal white adipose tissue (iWAT) concomitant with elevated energy expenditure, reduced obesity and ameliorated glucose tolerance compared to control littermates. H3K18cr and H3K18ac levels were elevated after MS275 treatment. MS275 also promoted the transcription of Pgc1α and Ucp1 by enhancing the enrichment of H3K18cr and H3K18ac in the Pgc1α/Ucp1 enhancer and promoter, with a notable increase in H3K18cr. Mechanistically, the deletion of Hdac1 in beige adipocyte increases H3K18cr levels in enhancers and promoters of Pgc1α and Ucp1 genes, regulated the chromosomal state, thereby affecting the transcription of Pgc1α/Ucp1. Taken together, HDAC1 inhibits beige adipocyte-mediated thermogenesis through histone crotonylation of Pgc1a/Ucp1. This finding may provide a therapeutic strategy through increasing energy expenditure in obesity and related metabolic disorders.

Obesity Characteristics Are Poor Predictors of Genetic Mutations Associated with Obesity

BACKGROUND

The genetic contribution to obesity is substantial and may underpin the altered pathophysiology. One such pathway involves melanocortin signaling in the hypothalamus. Genetic variants can cause dysregulation in the central melanocortin pathway that can result in early onset of hyperphagia and obesity. Clinically identifying patients who are at risk of known genetic mutations is challenging. The main purpose of this study was to identify associations between the clinico-demographical characteristics and the presence of a genetic mutation associated with obesity.

METHODS

We tested samples from 238 adult patients with class III obesity between October 2021 to February 2023 using next-generation sequencing (NGS) (Illumina, NovaSeq 6000 Sequencing System). The results were classified as "no variant identified" or "variant identified".

RESULTS

107 patients (45%) had one or more gene mutation in the leptin-melanocortin pathway. All variants were heterozygous. The patients with a gene mutation had a BMI of 48.4 ± 0.8 kg/m2 (mean ± SEM), and those without a gene mutation had a BMI of 49.4 ± 0.7 kg/m2 (p = 0.4). The mean age of onset of obesity in patients with a gene mutation was 13.9 ± 1.3 years and for those without gene mutations was 11.5 ± 0.9 years (p = 0.1). The incidence of hyperphagia as a child was also not predictive (p = 0.4).

CONCLUSIONS

Gene mutations associated with obesity in patients with a BMI > 40 kg/m2 are common. However, a patient's BMI, age of onset of obesity, or age of onset of hyperphagia did not help to differentiate which patients may be more likely to have genetic mutations associated with obesity.

Trans-ethnic polygenic risk scores for body mass index: An international hundred K+ cohorts consortium study

BACKGROUND

While polygenic risk scores hold significant promise in estimating an individual's risk of developing a complex trait such as obesity, their application in the clinic has, to date, been limited by a lack of data from non-European populations. As a collaboration model of the International Hundred K+ Cohorts Consortium (IHCC), we endeavored to develop a globally applicable trans-ethnic PRS for body mass index (BMI) through this relatively new international effort.

METHODS

The polygenic risk score (PRS) model was developed, trained and tested at the Center for Applied Genomics (CAG) of The Children's Hospital of Philadelphia (CHOP) based on a BMI meta-analysis from the GIANT consortium. The validated PRS models were subsequently disseminated to the participating sites. Scores were generated by each site locally on their cohorts and summary statistics returned to CAG for final analysis.

RESULTS

We show that in the absence of a well powered trans-ethnic GWAS from which to derive marker SNPs and effect estimates for PRS, trans-ethnic scores can be generated from European ancestry GWAS using Bayesian approaches such as LDpred, by adjusting the summary statistics using trans-ethnic linkage disequilibrium reference panels. The ported trans-ethnic scores outperform population specific-PRS across all non-European ancestry populations investigated including East Asians and three-way admixed Brazilian cohort.

CONCLUSIONS

Here we show that for a truly polygenic trait such as BMI adjusting the summary statistics of a well powered European ancestry study using trans-ethnic LD reference results in a score that is predictive across a range of ancestries including East Asians and three-way admixed Brazilians.

Cocaine-induced plasticity, motivation, and cue responsivity do not differ in obesity-prone vs obesity-resistant rats; implications for food addiction

RATIONALE

Compared to obesity-resistant rats, obesity-prone rats consume more food, work harder to obtain food, show greater motivational responses to food-cues, and show greater striatal plasticity in response to eating sugary/fatty foods. Therefore, it is possible that obesity-prone rats may also be more sensitive to the motivational properties of cocaine and cocaine-paired cues, and to plasticity induced by cocaine.

OBJECTIVE

To examine baseline differences in motivation for cocaine and effects of intermittent access (IntA) cocaine self-administration on cocaine motivation, neurobehavioral responsivity to cocaine-paired cues, and locomotor sensitization in male obesity-prone vs obesity-resistant rats.

METHODS

Intravenous cocaine self-administration was used to examine drug-taking and drug-seeking in males. Motivation for cocaine was measured using a within session threshold procedure. Cue-induced c-Fos expression in mesocorticolimbic regions was measured.

RESULTS

Drug-taking and drug-seeking, cue-induced c-Fos, locomotor sensitization, and preferred level of cocaine consumption (Q0) were similar between obesity-prone and obesity-resistant groups. Maximal responding during demand testing (Rmax) was lower in obesity-prone rats. IntA experience enhanced motivation for cocaine (Pmax) in obesity-prone rats.

CONCLUSIONS

The results do not support robust inherent differences in motivation for cocaine, cue-induced cocaine seeking, or neurobehavioral plasticity induced by IntA in obesity-prone vs obesity-resistant rats. This contrasts with previously established differences seen for food and food cues in these populations and shows that inherent enhancements in motivation for food and food-paired cues do not necessarily transfer to drugs and drug-paired cues.

Metabolic rate, sleep duration, and body temperature in evolution of mammals and birds: the influence of geological time of principal groups divergence

This study contains an analysis of basal metabolic rate (BMR) in 1817 endothermic species. The aim was to establish how metabolic scaling varies between the main groups of endotherms during evolution. The data for all the considered groups were combined and the common exponent in the allometric relationship between the BMR and body weight was established as b = 0.7248. Reduced to the common slope, the relative metabolic rate forms the following series: Neognathae – Passeriformes – 1.00, Neognathae – Non-Passeriformes – 0.75, Palaeognathae – 0.53, Eutheria – 0.57, Marsupialia – 0.44, and Monotremata – 0.26. The main finding is that the metabolic rate in the six main groups of mammals and birds consistently increases as the geological time of the group’s divergence approaches the present. In parallel, the average body temperature in the group rises, the duration of sleep decreases and the duration of activity increases. BMR in a taxon correlates with its evolutionary age: the later a clade diverged, the higher is its metabolic rate and the longer is its activity period; group exponents decrease as group divergence nears present times while with increase metabolic rate during activity, they not only do not decrease but can increase. Sleep duration in mammals was on average 40% longer than in birds while BMR, in contrast, was 40% higher in birds. The evolution of metabolic scaling, body temperature, sleep duration, and activity during the development of endothermic life forms is demonstrated, allowing for a better understanding of the underlying principles of endothermy formation.

Diet self-management: A qualitative study of college students' experiences and perspectives

Background

Overweight and obesity among college students have become an emergent public health concern, which may be effectively prevented by diet self-management (DSM). The purpose of this explorative study was to explore college students' experiences and perspectives on diet self-management (DSM), as well as its influencing factors.

Method

Thirty-three college students were recruited from different universities in China. A qualitative method was used to conduct semi-structured interviews with audio recording to explore their DSM experience and factors that influence DSM. Data were analyzed using thematic analysis to develop themes related to DSM.

Result

In the perception of what "good DSM" means, three themes and ten subthemes were identified: characteristics of good DSM (including 5 subthemes: regularity, balanced diet, no picky eating, good eating habits, and scientificity), method of good DSM (including three subthemes: self-control, adjusting, and making plans), and content of good DSM (including two subthemes: nutrition management and safety management). The influencing factors of DSM can be categorized into four levels of themes and 34 subthemes: individual, family, school, and social levels.

Conclusion

The results of this qualitative research highlighted the complexity and multi-dimension of DSM and its influencing factors. Our findings may help to inform diverse and needs-based intervention approaches to improve DSM and promote healthy diet among college students so as to prevent overweight and obesity.

Assessing 48 SNPs in Hypertensive Paediatric Patients and Young Adults with Review of Genetic Background of Essential Hypertension

Essential hypertension in paediatric patients and young adults is rising, mostly on account of obesity-related hypertension. Clinically, the difference between obese hypertensive and non-obese hypertensive individuals is evident; yet, the pathophysiology of essential and obesity-related hypertension is multifactorial, complex and not fully understood. The aim of our study was to obtain a comprehensive view of the clinical differences between obesity-related hypertension and hypertension in non-obese paediatric patients and young adults and to do genetic tests to possibly highlight some of the pathophysiological differences with a review of their genetic backgrounds. Four hundred and thirty-six hypertensive paediatric patients and young adults were included in the study, and a study of 48 single-nucleotide polymorphisms, using Kompetitive allele specific PCR, was conducted. The subjects were divided into 243 non-obese participants with hypertension and 193 obese participants with hypertension. The data for the clinical comparison of both groups were collected as well. The differences in some clinical and biochemical parameters were confirmed. Genetic tests showed a significant difference in one allele frequency between both groups in five SNPs: rs6232, rs6235, rs12145833, rs59744560 and rs9568856. In rs6235 and rs59744560, a direct effect of different allele states could be implied. Obesity-related hypertension at a young age differs from essential hypertension in those non-obese. The reported genetic differences could be important in understanding the complex pathophysiology of early-onset obesity-related hypertension and should be further evaluated.

Stomatin modulates adipogenesis through the ERK pathway and regulates fatty acid uptake and lipid droplet growth

Regulation of fatty acid uptake, lipid production and storage, and metabolism of lipid droplets (LDs), is closely related to lipid homeostasis, adipocyte hypertrophy and obesity. We report here that stomatin, a major constituent of lipid raft, participates in adipogenesis and adipocyte maturation by modulating related signaling pathways. In adipocyte-like cells, increased stomatin promotes LD growth or enlargements by facilitating LD-LD fusion. It also promotes fatty acid uptake from extracellular environment by recruiting effector molecules, such as FAT/CD36 translocase, to lipid rafts to promote internalization of fatty acids. Stomatin transgenic mice fed with high-fat diet exhibit obesity, insulin resistance and hepatic impairments; however, such phenotypes are not seen in transgenic animals fed with regular diet. Inhibitions of stomatin by gene knockdown or OB-1 inhibit adipogenic differentiation and LD growth through downregulation of PPAR_γ pathway. Effects of stomatin on PPAR_γ involves ERK signaling; however, an alternate pathway may also exist.

Stomatin is a component of lipid rafts. Here, Wu et al. show that stomatin modulates the differentiation and functions of adipocytes by regulating adipogenesis signaling and fatty acid influx such that with excessive calorie intake, increased stomatin induces adiposity.

Reviewed and updated Algorithm for Genetic Characterization of Syndromic Obesity Phenotypes

Background: Individuals with a phenotype of early-onset severe obesity associated with intellectual disability can have molecular diagnoses ranging from monogenic to complex genetic traits. Severe overweight is the major sign of a syndromic physical appearance and predicting the influence of a single gene and/or polygenic risk profile is extremely complicated among the majority of the cases. At present, considering rare monogenic bases as the principal etiology for the majority of obesity cases associated with intellectual disability is scientifically poor. The diversity of the molecular bases responsible for the two entities makes the appliance of the current routinely powerful genomics diagnostic tools essential. Objective: Clinical investigation of these difficult-to-diagnose patients requires pediatricians and neurologists to use optimized descriptions of signs and symptoms to improve genotype correlations. Methods: The use of modern integrated bioinformatics strategies which are conducted by experienced multidisciplinary clinical teams. Evaluation of the phenotype of the patient's family is also of importance. Results: The next step involves discarding the monogenic canonical obesity syndromes and considering infrequent unique molecular cases, and/or then polygenic bases. Adequate management of the application of the new technique and its diagnostic phases is essential for achieving good cost/efficiency balances. Conclusion: With the current clinical management, it is necessary to consider the potential coincidence of risk mutations for obesity in patients with genetic alterations that induce intellectual disability. In this review, we describe an updated algorithm for the molecular characterization and diagnosis of patients with a syndromic obesity phenotype.

Anti-adipogenic and Pro-lipolytic Effects on 3T3-L1 Preadipocytes by CX-4945, an Inhibitor of Casein Kinase 2

Casein kinase 2 (CK2) is a ubiquitously expressed serine/threonine kinase and is upregulated in human obesity. CX-4945 (Silmitasertib) is a CK2 inhibitor with anti-cancerous and anti-adipogenic activities. However, the anti-adipogenic and pro-lipolytic effects and the mode of action of CX-4945 in (pre)adipocytes remain elusive. Here, we explored the effects of CX-4945 on adipogenesis and lipolysis in differentiating and differentiated 3T3-L1 cells, a murine preadipocyte cell line. CX-4945 at 15 μM strongly reduced lipid droplet (LD) accumulation and triglyceride (TG) content in differentiating 3T3-L1 cells, indicating the drug’s anti-adipogenic effect. Mechanistically, CX-4945 reduced the expression levels of CCAAT/enhancer-binding protein-α (C/EBP-α), peroxisome proliferator-activated receptor-γ (PPAR-γ), fatty acid synthase (FAS), acetyl-CoA carboxylase (ACC), and perilipin A in differentiating 3T3-L1 cells. Strikingly, CX-4945 further increased the phosphorylation levels of cAMP-activated protein kinase (AMPK) and liver kinase B-1 (LKB-1) while decreasing the intracellular ATP content in differentiating 3T3-L1 cells. In differentiated 3T3-L1 cells, CX-4945 had abilities to stimulate glycerol release and elevate the phosphorylation levels of hormone-sensitive lipase (HSL), pointing to the drug’s pro-lipolytic effect. In addition, CX-4945 induced the activation of extracellular signal-regulated kinase-1/2 (ERK-1/2), and PD98059, an inhibitor of ERK-1/2, attenuated the CX4945-induced glycerol release and HSL phosphorylation in differentiated 3T3-L1 cells, indicating the drug’s ERK-1/2-dependent lipolysis. In summary, this investigation shows that CX-4945 has strong anti-adipogenic and pro-lipolytic effects on differentiating and differentiated 3T3-L1 cells, mediated by control of the expression and phosphorylation levels of CK2, C/EBP-α, PPAR-γ, FAS, ACC, perilipin A, AMPK, LKB-1, ERK-1/2, and HSL.

Prenatal Environmental Exposure to Persistent Organic Pollutants and Indices of Overweight and Cardiovascular Risk in Dutch Adolescents

Persistent organic pollutants (POPs) may have obesogenic effects. Knowledge about the effects of prenatal exposure to POPs on anthropometric measurements and metabolic parameters into adolescence is limited. Therefore, the aim of the current study was to determine whether prenatal environmental exposure to several POPs is associated with indices of overweight and cardiovascular risk in 13–15-year-old children. In this Dutch observational cohort study, 194 mother–infant pairs were included (1998–2002). Maternal pregnancy serum levels of PCBs, OH-PCBs, PBDEs, and other POPs were measured. At follow-up (2014–2016), levels of cholesterol, HDL-C, LDL-C, triglycerides, fasting insulin, fasting glucose, leptin, and adiponectin were measured in their children. The children’s height, weight, waist circumference, hip circumference, and blood pressure were measured. In total, 101 adolescents (14.4 ± 0.8 years; 53.7% of invited) participated of which 55 were boys. Mean BMI was 19.1 ± 3.6 kg/m² and mean BMI z-score 0.13 ± 1.14. Higher prenatal levels of PCBs were associated with lower levels of HDL-C and adiponectin in boys and higher levels of PBDEs with higher triglycerides in girls. We found significant differences by sex in the associations with OH-PCBs, with lower HDL-C and adiponectin, higher LDL-C/HDL-C ratio, fasting glucose, HOMA2-IR, height, and weight for boys. Our study indicates that higher prenatal exposure to PCBs, OH-PCBs, and PBDEs was associated with adolescent levels of some metabolic cardiovascular risk markers and hormones associated with the development of obesity and cardiovascular disease.

IL-1R-IRAKM-Slc25a1 signaling axis reprograms lipogenesis in adipocytes to promote diet-induced obesity in mice

Toll-like receptors/Interleukin-1 receptor signaling plays an important role in high-fat diet-induced adipose tissue dysfunction contributing to obesity-associated metabolic syndromes. Here, we show an unconventional IL-1R-IRAKM-Slc25a1 signaling axis in adipocytes that reprograms lipogenesis to promote diet-induced obesity. Adipocyte-specific deficiency of IRAKM reduces high-fat diet-induced body weight gain, increases whole body energy expenditure and improves insulin resistance, associated with decreased lipid accumulation and adipocyte cell sizes. IL-1β stimulation induces the translocation of IRAKM Myddosome to mitochondria to promote de novo lipogenesis in adipocytes. Mechanistically, IRAKM interacts with and phosphorylates mitochondrial citrate carrier Slc25a1 to promote IL-1β-induced mitochondrial citrate transport to cytosol and de novo lipogenesis. Moreover, IRAKM-Slc25a1 axis mediates IL-1β induced Pgc1a acetylation to regulate thermogenic gene expression in adipocytes. IRAKM kinase-inactivation also attenuates high-fat diet-induced obesity. Taken together, our study suggests that the IL-1R-IRAKM-Slc25a1 signaling axis tightly links inflammation and adipocyte metabolism, indicating a potential therapeutic target for obesity.

Exosomes from Human Placenta Choriodecidual Membrane-Derived Mesenchymal Stem Cells Mitigate Endoplasmic Reticulum Stress, Inflammation, and Lung Injury in Lipopolysaccharide-Treated Obese Mice

Endoplasmic reticulum (ER) stress mediates the effects of obesity on aggravating sepsis-induced lung injury. We investigated whether exosomes from human placenta choriodecidual membrane-derived mesenchymal stem cells (pcMSCs) can mitigate pulmonary ER stress, lung injury, and the mechanisms of inflammation, oxidation, and apoptosis in lipopolysaccharide-treated obese mice. Diet-induced obese (DIO) mice (adult male C57BL/6J mice fed with a 12-week high-fat diet) received lipopolysaccharide (10 mg/kg, i.p.; DIOLPS group) or lipopolysaccharide plus exosomes (1 × 108 particles/mouse, i.p.; DIOLPSExo group). Our data demonstrated lower levels of ER stress (upregulation of glucose-regulated protein 78, phosphorylated eukaryotic initiation factor 2α, and C/EBP homologous protein; p = 0.038, <0.001, and <0.001, respectively), inflammation (activation of nuclear factor-kB, hypoxia-inducible factor-1α, macrophages, and NLR family pyrin domain containing 3; upregulation of tumor necrosis factor-α, interleukin-1β, and interleukin-6; p = 0.03, <0.001, <0.001, <0.001, <0.001, <0.001, and <0.001, respectively), lipid peroxidation (p < 0.001), and apoptosis (DNA fragmentation, p = 0.003) in lung tissues, as well as lower lung injury level (decreases in tidal volume, peak inspiratory flow, and end expiratory volume; increases in resistance, injury score, and tissue water content; p < 0.001, <0.001, <0.001, <0.001, <0.001, and =0.002, respectively) in the DIOLPSExo group than in the DIOLPS group. In conclusion, exosomes from human pcMSCs mitigate pulmonary ER stress, inflammation, oxidation, apoptosis, and lung injury in lipopolysaccharide-treated obese mice.

Kisspeptin and the Genetic Obesity Interactome

BACKGROUND

Kisspeptin (encoded by the KISS1 gene in humans) is an excitatory neuromodulatory peptide implicated in multiple homeostatic systems, including anti-oxidation, glucose homeostasis, nutrition, locomotion, etc. Therefore, in the current obesity epidemic, kisspeptin is gaining increasing interest as a research objective.

AIM

To construct an updated interactome of genetic obesity, including the kisspeptin signal transduction pathway.

METHODS

Kisspeptin and obesity-related genes or gene products were extracted from the biomedical literature, and a network of functional associations was created.

RESULTS

The generated network contains 101 nodes corresponding to gene/gene products with known and/or predicted interactions. In this interactome, KISS1 and KISS1R are connected directly to the luteinizing hormone receptor (LHCGR), gonadotropin-releasing hormone receptor (GNRH1), and indirectly, through the latter, to proopiomelanocortin (POMC), glucagon, leptin (LEP), and/or pro-protein convertase subtilisin/kexin-type 1 (PCSK1), all of which are critically implicated in obesity disorders.

CONCLUSIONS

Our updated obesidome includes kisspeptin and its connections to the genetic obesity signalosome with 12 major hubs: glucagon (GCG), insulin (INS), arginine vasopressin (AVP), G protein subunit beta 1 (GNB1) and proopiomelanocortin (POMC), melanocortin 4 receptor (MC4R), leptin (LEP), gonadotropin-releasing hormone 1 (GNRH1), adrenoceptor beta 2 and 3 (ADRB2-3), glucagon-like peptide 1 receptor (GLP1R), and melanocortin 3 receptor (MC3R) genes were identified as major "hubs" for genetic obesity, providing novel insight into the body's energy homeostasis.

The Specific Impact of Nutrition and Physical Activity on Adolescents' Body Composition and Energy Balance

Purpose: The aim of the present study was to identify the contribution of nutrition, physical activity (PA), and total energy intake and expenditure on body weight and composition in adolescents. Methods: Body composition, PA, and dietary intakes from 904 Greek adolescents (446 boys and 458 girls; Age: 14.6 ± 1.5 yrs), were evaluated. All participants were assigned into three groups according to their age-sex adjusted Fat Mass Index: (A) Normal weight (N; N = 503), (B) Overweight (OW; N = 253), and (C) Obese (O; N = 148). Results: Significant differences were found for body weight and composition, basal metabolic rate (BMR) expressed per kg of body mass (normal weight children exhibited the highest values), physical-total energy expenditure, and energy balances between the groups (η²: 0.138 to 0.657; p < .05). In contrast, no differences were found for macronutrients' and total energy intakes, food consumption and quality (η²: 0.002 to 0.099; p > .05) between the three examined groups. Strong, negative correlations were observed between body weight, body fat percentage, PA, and total energy expenditure (r: -0.311 to -0.810; p < .001). Lower, negative correlations were found between body weight, body fat percentage, and macronutrients' daily intakes (r:-0.235 to -0.432; p < .05). BMR and total energy expenditure had strong, negative relative strengths for the determination of body weight and fat percentage. Conclusions: In conclusion, it seems that BMR, PA, and total daily energy expenditure expressed per body weight and not the nutritional and total energy intakes, were the primary determinant parameters of body composition and weight in adolescents.

Contrasting Narratives of Race and Fatness in Covid-19

The slogan that 'the virus doesn't discriminate' has been belied by the emergence of stark and persistent disparities in rates of infection, hospitalisation, and death from Covid-19 between various social groups. I focus on two groups that have been disproportionately affected, and that have been constructed or designated as particularly 'at-risk' during the Covid-19 pandemic: racial or ethnic minorities and fat people. I trace the range of narratives that have arisen in the context of explaining these disparities, in both the scientific literature and wider expert and public discourse. I show that the scientific and public narratives around these groups have differed significantly, revealing contested and competing conceptions of the basis of these categories themselves. These different conceptions have important impacts on the kinds of interventions that become possible or desirable. I show that in the case of racial or ethnic disparities, genetic narratives have been combatted by a strong focus on structural racism as a driver of pandemic inequalities. However, in the case of fatness, individualising and stigmatising narratives have dominated discussions. I suggest that, given racial or ethnic differences in prevalence of fatness, and scholarship casting anti-fatness as historically racialised, the stigmatisation of fatness disproportionately affects racial or ethnic minorities in terms of placing individual blame or responsibility for the increased burden of Covid-19 on these groups. Despite widespread acknowledgement of the role of structural racism in driving racial inequalities in the burden of Covid-19, anti-obesity rhetoric and research provides a 'backdoor' to placing blame on individuals from racial minorities.

Obesity Inhibits Angiogenesis Through TWIST1-SLIT2 Signaling

Angiogenesis is required for functional adipose tissue maintenance, remodeling, and expansion. Physiologically balanced adipogenesis and angiogenesis are inhibited in subcutaneous adipose tissue in obese humans. However, the mechanism by which angiogenesis is inhibited in obese adipose tissue is not fully understood. Transcription factor TWIST1 controls angiogenesis and vascular function. TWIST1 expression is lower in obese human adipose tissues. Here, we have demonstrated that angiogenesis is inhibited in endothelial cells (ECs) isolated from adipose tissues of obese humans through TWIST1-SLIT2 signaling. The levels of TWIST1 and SLIT2 are lower in ECs isolated from obese human adipose tissues compared to those from lean tissues. Knockdown of TWIST1 in lean human adipose ECs decreases, while overexpression of TWIST1 in obese adipose ECs restores SLIT2 expression. DNA synthesis and cell migration are inhibited in obese adipose ECs and the effects are restored by TWIST1 overexpression. Obese adipose ECs also inhibit blood vessel formation in the gel subcutaneously implanted in mice, while these effects are restored when gels are mixed with SLIT2 or supplemented with ECs overexpressing TWIST1. These findings suggest that obesity impairs adipose tissue angiogenesis through TWIST1-SLIT2 signaling.

Epigenome-wide association study detects a novel loci associated with central obesity in healthy subjects

Background and aims

Central obesity is a condition that poses a significant risk to global health and requires the employment of novel scientific methods for exploration. The objective of this study is to use DNA methylation analysis to detect DNA methylation loci linked to obesity phenotypes, i.e. waist circumference and waist-to-hip ratio adjusted for BMI.

Methods and results

Two-hundred and ten healthy European participants from the STANISLAS Family Study (SFS), comprising 73 nuclear families, were comprehensively assessed for methylation status using Illumina Infinium HumanMethylation450 BeadChip. An epigenome-wide association study was performed, which identified a CpG site cg16170243 located on chromosome 18q21.2 significantly associated with waist circumference, after adjusting for BMI (β = 2.32, SE = 0.41, P_adj = 0.048). Cg16170243 corresponds to a 50 bp-length human methylation oligoprobe located within the AC090241.2 gene that overlaps ST8SIA5 gene. No significant association was observed with waist-to-hip ratio adjusted for BMI (P_adj > 0.05).

Conclusions

A novel association between DNA methylation and WC was identified, which is demonstrating that epigenetic mechanisms may have a significant impact on waist circumference ratio in healthy individuals. Further studies are warranted to address the causal effects of this association.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-021-01077-9.

Association of Genetic Variants With Body-Mass Index and Blood Pressure in Adolescents: A Replication Study

The strong correlation between adiposity and blood pressure (BP) might be explained in part by shared genetic risk factors. A recent study identified three nucleotide variants [rs16933812 (PAX5), rs7638110 (MRPS22), and rs9930333 (FTO)] associated with both body mass index (BMI) and systolic blood pressure (SBP) in adolescents age 12-18years. We attempted to replicate these findings in a sample of adolescents of similar age. A total of 713 adolescents were genotyped and had anthropometric indicators and blood pressure measured at age 13, 15, 17, and 24years. Using linear mixed models, we assessed associations of these variants with BMI and SBP. In our data, rs9930333 (FTO) was associated with body mass index, but not systolic blood pressure. Neither rs16933812 (PAX5) nor rs7638110 (MRPS22) were associated with body mass index or systolic blood pressure. Although, differences in phenotypic definitions and in genetic architecture across populations may explain some of the discrepancy across studies, nucleotide variant selection in the initial study may have led to false-positive results that could not be replicated.

Coronary Artery Disease: Association Study of 5 Loci with Angiographic Indices of Disease Severity

Background

Different common gene variants were related to coronary artery disease (CAD) in many studies. Yet, the relation of these loci to the severity of CAD is not completely elucidated.

Methods

We enrolled 520 subjects (315 CAD cases and 205 controls). CAD presence and extension were assessed by coronary angiography (CAG). Genotyping of five SNPs (namely, rs2230806 (1051G > A) in ABCA1 on chromosome 9, rs2075291 (553G > T) in ApoA5 on chromosome 11, rs320 in LPL on chromosome 8 intron (T → G at position 481), rs10757278 (c.22114477A > G), and rs2383206 (c.22115026 A > G) on chromosome 9p21 locus) was performed by allele-specific PCR. The degree and site of arterial lesions were used to classify patients, tested for association with CAD severity, and related to allele dosage.

Results

The polymorphisms rs2383206 and rs10757278 showed significant associations with 2- and 3-vessel coronary disease (p =0.003 and 0.006, respectively). The homozygous GG genotypes of rs10757278 was associated with higher frequency of left anterior descending (LAD), right coronary artery (RCA) and left circumflex (LCX) diseases (p =0.002, 0.016 and 0.002, respectively). The GG genotypes of rs2383206 were found in higher percentage in patients with left main (LM) trunk and left circumflex (LCX) diseases (p = 0.013 and 0.002, respectively).

Conclusion

SNPs rs10757278 and rs2383206 allele dosage could predict CAD severity in the Saudi Arab population.

Obesity 2021: Rejecting Old Misconceptions and Embracing a New Paradigm to Improve Outcomes

Despite the best efforts of many health care workers and increasing knowledge about the human energy regulatory system and dietary and exercise science, rates of obesity continue to rise. In the past 40 years, not a single country in the world has experienced a reduction in the prevalence of obesity. Over these same 40 years, treatment options such as medications, as well as bariatric and other surgical procedures, have continued to expand. Why then, are we not seeing more improvement in obesity outcomes? This commentary hypothesizes that it is due to a combination of factors. These factors include an individual's genetic predisposition combined with the modern obesogenic environment, an energy regulatory system that defends fat mass and fights loss, obesity not being seen as a disease state, and individual and societal weight bias. (Clin Ther. 2021;43:XXX-XXX) © 2021 Elsevier HS Journals, Inc.

Perinatal Nutritional and Metabolic Pathways: Early Origins of Chronic Lung Diseases

Lung development is not completed at birth, but expands beyond infancy, rendering the lung highly susceptible to injury. Exposure to various influences during a critical window of organ growth can interfere with the finely-tuned process of development and induce pathological processes with aberrant alveolarization and long-term structural and functional sequelae. This concept of developmental origins of chronic disease has been coined as perinatal programming. Some adverse perinatal factors, including prematurity along with respiratory support, are well-recognized to induce bronchopulmonary dysplasia (BPD), a neonatal chronic lung disease that is characterized by arrest of alveolar and microvascular formation as well as lung matrix remodeling. While the pathogenesis of various experimental models focus on oxygen toxicity, mechanical ventilation and inflammation, the role of nutrition before and after birth remain poorly investigated. There is accumulating clinical and experimental evidence that intrauterine growth restriction (IUGR) as a consequence of limited nutritive supply due to placental insufficiency or maternal malnutrition is a major risk factor for BPD and impaired lung function later in life. In contrast, a surplus of nutrition with perinatal maternal obesity, accelerated postnatal weight gain and early childhood obesity is associated with wheezing and adverse clinical course of chronic lung diseases, such as asthma. While the link between perinatal nutrition and lung health has been described, the underlying mechanisms remain poorly understood. There are initial data showing that inflammatory and nutrient sensing processes are involved in programming of alveolarization, pulmonary angiogenesis, and composition of extracellular matrix. Here, we provide a comprehensive overview of the current knowledge regarding the impact of perinatal metabolism and nutrition on the lung and beyond the cardiopulmonary system as well as possible mechanisms determining the individual susceptibility to CLD early in life. We aim to emphasize the importance of unraveling the mechanisms of perinatal metabolic programming to develop novel preventive and therapeutic avenues.

Study of LEP, MRAP2 and POMC genes as potential causes of severe obesity in Brazilian patients

PURPOSE

Monogenic forms of obesity are caused by single-gene variants which affect the energy homeostasis by increasing food intake and decreasing energy expenditure. Most of these variants result from disruption of the leptin-melanocortin signaling, which can cause severe early-onset obesity and hyperphagia. These mutation have been identified in genes encoding essential proteins to this pathway, including leptin (LEP), melanocortin 2 receptor accessory proteins 2 (MRAP2) and proopiomelanocortin (POMC). We aimed to investigate the prevalence of LEP, MRAP2 and POMC rare variants in severely obese adults, who developed obesity during childhood. To the best of our knowledge, this is the first study screening rare variants of these genes in patients from Brazil.

METHODS

A total of 122 Brazilian severely obese patients (BMI ≥ 35 kg/m²) were screened for the coding regions of LEP, MRAP2 and POMC by Sanger sequencing. All patients are candidates to the bariatric surgery. Clinical characteristics were described in patients with novel and/or potentially pathogenic variants.

RESULTS

Sixteen different variants were identified in these genes, of which two were novel. Among them, one previous variant with potentially deleterious effect in MRAP2 (p.Arg125Cys) was found. In addition, two heterozygous mutations in POMC (p.Phe87Leu and p.Arg90Leu) were predicted to impair protein function. We also observed a POMC homozygous 9 bp insertion (p.Gly99_Ala100insSerSerGly) in three patients. No pathogenic variant was observed in LEP.

CONCLUSION

Our study described for the first time the prevalence of rare potentially pathogenic MRAP2 and POMC variants in a cohort of Brazilian severely obese adults.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

Comparison of short-term hypocaloric high-protein diets with a hypocaloric Mediterranean diet: Effect on body composition and health-related blood markers in overweight and sedentary young participants

OBJECTIVES

The aim of the present study was to compare the short-term effects of a hypocaloric Mediterranean diet and two high protein diets, with and without whey protein supplementation, on body composition, lipidemic profile, and inflammation and muscle-damage blood indices in overweight, sedentary, young participants.

METHODS

Thirty-three young, overweight, male and female participants (mean ± SD age: 22.8 ± 4.8 y; body mass: 85.5 ± 10.2 kg; body fat percentage: 34.3% ± 8.1%) were randomly allocated to three different hypocaloric (-700 kcal/d) diets: a Mediterranean diet (MD; n = 10), a high-protein diet (HP; n = 10) diet, and a high-protein diet with whey supplementation (n = 10). The intervention lasted 6 wk. Body composition and biochemical indices were evaluated 1 wk before and after the nutritional interventions.

RESULTS

Body and fat mass were decreased in the MD and HP groups (-3.5% ± 1.1% and -5.9% ± 4.2% for body and fat mass respectively in MD, and -1.7% ± 1.2% and -2.0% ± 1.8% for body and fat mass respectively in HP;P < 0.05), with no significant decline of fat-free mass observed in the MD group. The MD group's diet beneficially altered the lipid profile (P < 0.05), but the HP and HPW groups' diets did not induce significant changes. Subclinical inflammation and muscle-damage indices significantly increased in the HP and HPW groups (7.4% ± 3.5% and 66.6% ± 40.1% for neutrophils and CRP respectively in HP, and 14.3% ± 6.4% and 266.6% ± 55.1% for neutrophils and CRP respectively in HPW; P < 0.05) but decreased in the MD group (1.8% ± 1.2% and -33.3% ± 10.1% for neutrophils and CRP respectivelyc; P < 0.05). Energy intake of carbohydrates and proteins were significantly related to the changes in body composition and biochemical blood markers (r = -0.389 and -0.889; P < 0.05).

CONCLUSIONS

Among the three hypocaloric diets, only the Mediterranean diet induced positive changes in body composition and metabolic profile in overweight, sedentary individuals.

LEP (-2548G>A LEP) and LEPR (223Gln>Arg, 109Lys>Arg) polymorphisms as breast cancer risk factors in the Polish female population

On a global scale, breast cancer is the most common type of cancer in women, and it is still a growing problem. Therefore, new prognostic or diagnostic markers are required that would facilitate the assessment of patients or provide more efficient therapy, respectively. In these studies, we analyzed the contribution of LEP (2548G>A) and LEPR (109 Lys>Arg and 223Gln>Arg) genes polymorphisms to the risk of breast cancer development. The study involved 209 women aged 59.6 ± 11 years diagnosed with breast cancer and 202 healthy women aged 57.8 ± 8.2 years, who were blood donors. Polymorphism were evaluated by PCR–RFLP reaction followed by the verification of part of the samples by sequencing. The results of the study confirmed obesity as a significant breast cancer development risk factor in Polish women. However, no significant association between the studied polymorphisms and breast cancer risk or severity of the neoplastic disease was found. Interestingly, it was shown that wild type 223Gln>Gln leptin receptor (LEPR) was statistically more common in women with human epidermal growth factor receptor 2 negative (HER2−) than human epidermal groth factor receptor 2 positive (HER2+) breast cancer and wild type form of 2548G>A LEP was more common in women with progesterone receptor positive (PR+) than progesterone receptor negative (PR−) breast cancer. Studied polymorphisms of the LEP and LEPR genes do not increase breast cancer risk in the population of Polish women. However, they can affect PR an HER receptors expression and thus the severity of the disease. Noteworthy, this interesting correlation is being reported for the first time and might constitute an essential contribution to the identification of molecular mechanisms of carcinogenesis.

Characterization of Differentially Expressed Circulating miRNAs in Metabolically Healthy versus Unhealthy Obesity

Obese individuals without metabolic comorbidities are categorized as metabolically healthy obese (MHO). MicroRNAs (miRNAs) may be implicated in MHO. This cross-sectional study explores the link between circulating miRNAs and the main components of metabolic syndrome (MetS) in the context of obesity. We also examine oxidative stress biomarkers in MHO vs. metabolically unhealthy obesity (MUO). We analysed 3536 serum miRNAs in 20 middle-aged obese individuals: 10 MHO and 10 MUO. A total of 159 miRNAs were differentially expressed, of which, 72 miRNAs (45.2%) were higher and 87 miRNAs (54.7%) were lower in the MUO group. In addition, miRNAs related to insulin signalling and lipid metabolism pathways were upregulated in the MUO group. Among these miRNAs, hsa-miR-6796-5p and hsa-miR-4697-3p, which regulate oxidative stress, showed significant correlations with glucose, triglycerides, HbA1c and HDLc. Our results provide evidence of a pattern of differentially expressed miRNAs in obesity according to MetS, and identify those related to insulin resistance and lipid metabolism pathways.

A Novel Loss of Function Melanocortin-4-Receptor Mutation (MC4R-F313Sfs*29) in Morbid Obesity

CONTEXT

Melanocortin receptor-4 (MC4R) gene mutations are associated with early-onset severe obesity, and the identification of potential pathological variants is crucial for the clinical management of patients with obesity.

OBJECTIVE

To explore whether and how a novel heterozygous MC4R variant (MC4R-F313Sfs*29), identified in a young boy (body mass index [BMI] 38.8 kg/m2) during a mutation analysis conducted in a cohort of patients with obesity, plays a determinant pathophysiological role in the obesity development.

DESIGN SETTING AND PATIENTS

The genetic screening was carried out in a total of 209 unrelated patients with obesity (BMI ≥ 35 kg/m2). Structural and functional characterization of the F313Sfs*29-mutated MC4R was performed using computational approaches and in vitro, using HEK293 cells transfected with genetically encoded biosensors for cAMP and Ca2+.

RESULTS

The F313Sfs*29 was the only variant identified. In vitro experiments showed that HEK293 cells transfected with the mutated form of MC4R did not increase intracellular cAMP or Ca2+ levels after stimulation with a specific agonist in comparison with HEK293 cells transfected with the wild type form of MC4R (∆R/R0 = -90% ± 8%; P < 0.001). In silico modeling showed that the F313Sfs*29 mutation causes a major reorganization in the cytosolic domain of MC4R, thus reducing the affinity of the putative GalphaS binding site.

CONCLUSIONS

The newly discovered F313Sfs*29 variant of MC4R may be involved in the impairment of α-MSH-induced cAMP and Ca2+ signaling, blunting intracellular G protein-mediated signal transduction. This alteration might have led to the dysregulation of satiety signaling, resulting in hyperphagia and early onset of obesity.

The current review of adolescent obesity: the role of genetic factors

Obesity, a complex, multi-factor and heterogeneous condition, is thought to result from the interaction of environmental and genetic factors. Considering the result of adolescence obesity in adulthood, the role of genetic factors comes to the fore. Recently, many genome-wide association studies (GWAS) have been conducted and many loci associated with adiposity have been identified. In adolescents, the strongest association with obesity has been found in single nucleotide polymorphisms (SNP) in the FTO gene. Besides FTO, GWAS showed consistent effects between variants in MC4R, TMEM18, TNNI3K, SEC16B, GNPDA2, POMC and obesity. However, these variants may not have similar effects for all ethnic groups. Although recently genetic factors are considered to contribute to obesity, relatively little is known about the specific loci related to obesity and the mechanisms by which they cause obesity.

Omega-3 Polyunsaturated Fatty Acids Prevent Nonalcoholic Steatohepatitis (NASH) and Stimulate Adipogenesis

The increasing impact of obesity on global human health intensifies the importance of studies focusing on agents interfering with the metabolism and remodeling not only of the white adipose tissue (WAT) but also of the liver. In the present study, we have addressed the impact of n-3 PUFA in adipose cells' proliferation and adipogenesis, as well as in the hepatic lipid profile and morphology. Mice were induced to obesity by the consumption of a high-fat diet (HFD) for 16 weeks. At the 9th week, the treatment with fish oil (FO) was initiated and maintained until the end of the period. The FO treatment reduced the animals' body mass, plasma lipids, glucose, plasma transaminases, liver mass, triacylglycerol, and cholesterol liver content when compared to animals consuming only HFD. FO also decreased the inguinal (ing) WAT mass, reduced adipocyte volume, increased adipose cellularity (hyperplasia), and increased the proliferation of adipose-derived stromal cells (AdSCs) which corroborates the increment in the proliferation of 3T3-L1 pre-adipocytes or AdSCs treated in vitro with n-3 PUFA. After submitting the in vitro treated (n-3 PUFA) cells, 3T3-L1 and AdSCs, to an adipogenic cocktail, there was an increase in the mRNA expression of adipogenic transcriptional factors and other late adipocyte markers, as well as an increase in lipid accumulation when compared to not treated cells. Finally, the expression of browning-related genes was also higher in the n-3 PUFA treated group. We conclude that n-3 PUFA exerts an attenuating effect on body mass, dyslipidemia, and hepatic steatosis induced by HFD. FO treatment led to decreasing adiposity and adipocyte hypertrophy in ingWAT while increasing hyperplasia. Data suggest that FO treatment might induce recruitment (by increased proliferation and differentiation) of new adipocytes (white and/or beige) to the ingWAT, which is fundamental for the healthy expansion of WAT.

Plant terpenes on treating cardiovascular and metabolic disease: a review

The use of medicinal plants as a therapy alternative is old as human existence itself. Nowadays, the search for effective molecules for chronic diseases treatments has increased. The cardiometabolic disorders still the main cause of death worldwide and plants may offer potential pharmacological innovative approaches to treat and prevent diseases. In the range of plant molecules are inserted the terpenes, which constituent essential elements with several pharmacological characteristics and applications, including cardiovascular and metabolic properties. Thus, the aim of the present review is to update the terpenes use on chronic disorders such as obesity, diabetes, hypertension and vascular conditions. The review includes a brief terpenes description based on the scientific literature in addition to data collected from secondary sources such as books and conference proceedings. We concluded that terpenes could act as adjuvant or main alternative treatment (when started earlier) to improve cardiometabolic diseases, contributing to reduce side effects of conventional drugs, in addition to preserving ethnopharmacological knowledge.

Increase in PPARγ inhibitory phosphorylation by Fetuin-A through the activation of Ras-MEK-ERK pathway causes insulin resistance

Obesity induced insulin resistance is primarily regulated by the inhibitory phosphorylation of peroxisome proliferator-activated receptor γ at serine 273 (PPARγS273) which has been shown to be regulated by MEK and ERK. An upstream regulatory molecule of this pathway could be a therapeutic option. Here we analyzed the involvement of Fetuin-A (FetA), a key hepato-adipokine implicated in insulin resistance, as an upstream regulator molecule for the regulation of PPARγ inhibitory phosphorylation. Mice fed with standard diet (SD), high fat diet (HFD) and HFD with FetA knockdown (HFD-FetA^KD) were used to examine the role of FetA on PPARγS273 phosphorylation in adipocytes. The mechanism of regulation and its effect on skeletal muscle were studied using primary adipocytes, 3T3-L1 (preadipocyte) and C2C12 (myotube) cell lines. Increased FetA in HFD mice strongly correlated with augmentation of PPARγS273 phosphorylation in inflamed adipocytes while knockdown of FetA suppressed it. This effect of FetA was mediated through the activation of Ras which in turn activated MEK and ERK. On addressing how FetA could stimulate activation of Ras, we found that FetA triggered TNFα in inflamed adipocytes which induced Ras activation. The ensuing sharp fall in adiponectin level attenuated AMPK activation in skeletal muscle cells affecting mitochondrial ATP production. Our data reveal the essential role of FetA induced activation of Ras in regulating PPARγ inhibitory phosphorylation through Ras-MEK-ERK pathway which downregulates adiponectin disrupting skeletal muscle mitochondrial bioenergetics. Thus, FetA mediated PPARγ inactivation has adverse consequences upon adipocyte-myocyte crosstalk leading to disruption of energy homeostasis and loss of insulin sensitivity.

Identification of a Rare and Potential Pathogenic MC4R Variant in a Brazilian Patient With Adulthood-Onset Severe Obesity

Background

The melanocortinergic pathway orchestrates the energy homeostasis and impairments in this system often lead to an increase in body weight. Rare variants in the melanocortin 4 receptor (MC4R) gene resulting in partial or complete loss of function have been described with autosomal co-dominant inheritance. These mutations are the most common cause of non-syndromic monogenic obesity. In this context, this study aimed to sequence the MC4R gene in a Brazilian cohort of adults with severe obesity.

Methods

This study included 163 unrelated probands with Body Mass Index (BMI) ≥ 35 kg/m², stratified into three groups, according to the period of obesity onset. From the total sample, 25 patients were enrolled in the childhood-onset group (0–11 years), 19 patients in the adolescence/youth-onset group (12–21 years), and 119 patients in the adult-onset group (>21 years). Blood pressure, anthropometric and biochemical characteristics were obtained, and the MC4R coding region of each subject’s DNA was assessed using automated Sanger sequencing.

Results

Significant anthropometric differences between the groups were observed. Higher body weight and BMI medians were found in patients with childhood-onset or adolescence/youth-onset when compared to the adulthood-onset obesity group. A total of five mutations were identified, including four missense variants: p.Ser36Thr, p.Val103Ile, p.Ala175Thr, and p.Ile251Leu. Additionally, we observed one synonymous variant (p.Ile198=). The p.Ala175Thr variant was identified in a female case with severe obesity and adulthood-onset. This variant was previously described as a partial loss-of-function mutation, in which the minor allele poses dominant-negative effect, probably resulting in reduced cAMP activity.

Conclusion

This study showed a prevalence of common and rare variants in a cohort of Brazilian adults with severe obesity and candidates to bariatric surgery. We have identified a rare potentially pathogenic MC4R variant in a Brazilian patient with severe and adulthood-onset obesity.

Uncovering epigenetic landscape: a new path for biomarkers identification and drug development

Scientific advances in recent decades have revealed an incredible degree of plasticity in gene expression in response to various environmental, nutritional, physiological, pathological, and behavioral conditions. Epigenetics emerges in this sense, as the link between the internal (genetic) and external (environmental) factors underlying the expression of the phenotype. Methylation of DNA and histone post-translationa modifications are canonical epigenetic events. Additionally, noncoding RNAs molecules (microRNAs and lncRNAs) have also been proposed as another layer of epigenetic regulation. Together, these events are responsible for regulating gene expression throughout life, controlling cellular fate in both normal and pathological development. Despite being a relatively recent science, epigenetics has been arousing the interest of researchers from different segments of the life sciences and the general public. This review highlights the recent advances in the characterization of the epigenetic events and points promising use of these brands for the diagnosis, prognosis, and therapy of diseases. We also present several classes of epigenetic modifying compounds with therapeutic applications (so-call epidrugs) and their current status in clinical trials and approved by the FDA. In summary, hopefully, we provide the reader with theoretical bases for a better understanding of the epigenetic mechanisms and of the promising application of these marks and events in the medical clinic.

Changes in gut microbial flora after Roux-en-Y gastric bypass and sleeve gastrectomy and their effects on post-operative weight loss

Bariatric surgery affects gut microbial flora due to the anatomical and physiological changes it causes in the gastrointestinal tract. Understanding the interaction between the gut flora, the type of bariatric surgery and weight loss may help improve bariatric surgery outcomes. This study was designed to compare the effects of Roux-en-Y Gastric Bypass (RYGB) and Sleeve Gastrectomy (SG) on two main phyla of the gut microbiota in humans and evaluate their potential effect on weight changes. Thirty morbidly obese patients were divided into two groups and underwent laparoscopic SG or laparoscopic RYGB. The patients' weight changes and fecal samples were evaluated at baseline and 6 months after the surgery. A microbial flora count was carried out of the phyla Bacteroidetes and Firmicutes and Bacteroides Fragilis. Changes in the abundance of the flora and their correlation with weight loss were analyzed. After 6 months, the patients with a history of RYGB showed a significant decrease in stool Bacteroidetes while the reduction in the SG group was insignificant. Firmicutes abundance was almost unchanged following SG and RYGB. There was no significant change in Bacteroides Fragilis abundance in either of the two groups, but a positive correlation was observed between Bacteroides Fragilis and weight loss after SG and RYGB. Bariatric surgery can affect gut microbiota. It can be concluded that these changes are dependent on many factors and may play a role in weight loss.

Anti-obesity potentiality of Tapra fish (Opisthopterus tardoore) oil

In this present investigation, we have extracted and characterized the Tapra fish oil as well as applied it to evaluate anti-obesity potentiality. The Tapra fish oil had 1.14 ± 0.10 mg KOH/g of acid value, 129.8 ± 5.09 mg KOH/g of saponification number, 2.67 ± 0.67 mEq/kg of peroxide value, 121.9 ± 2.14 mg of iodine value, and 17.67 ± 1.45 totox value. Gas Chromatography-Mass Spectrometric analysis clearly revealed the presence of nine different fatty acids. When the fish oil was applied to high-fat diet-induced obese mice, it showed significant reduction of body weight, Body Mass Index, and serum lipid profiles compared to the high-fat diet-induced obese mice. The levels of leptin and TNF-α were moderately reduced in fish oil treated high-fat diet-induced obese mice than control obese mice. In conclusion, the Tapra fish oil was enriched with essential fatty acids and it could be used as an antiobese food supplement. PRACTICAL APPLICATIONS: Considering the adverse effects of drugs used for the treatment of obesity, there is always a need to find out the alternatives. While the anti-obesity potentialities of different sea fish oil have been documented, the same for the Tapra fish (Opisthopterus tardoore) oil has not been studied at all. The extracted Tapra fish oil was found good in quality. Administration of fish oil in the mice exhibited anti-obesity effect in terms of lowering body weight, Body Mass Index, and serum lipid profiles, leptin, and TNF-α in mice model. These findings are fostering new therapeutic approaches to obesity treatment.

Adolescent Obesity and Eating Disorders: Can Calorie Restriction have a Positive Impact

Background:

The current obesogenic environment with relatively increased affordability and availability of high calorie food and beverages, has led to an alarming increase in the prevalence of obesity and related lifestyle disorders in children and adolescents, predisposing them to accelerated aging. The increased prevalence may be due to the eating behavior of adolescents, their genetic and molecular etiology and/or due to the impact of psychological stress and their wrong lifestyle choices. Calorie restriction has been extensively researched for reducing the obesity in adolescents and adults but is yet to be successfully implemented.

Objective:

The present review paper focuses on the types of calorie restriction diets, the role of its mimics and the nutrigenomic mechanisms that may be helpful in reducing obesity and related disorders in the adolescents. The role of behavioral therapeutic techniques and physical activity has also been highlighted in addition to the calorie restricted diet for bringing about an overall lifestyle modification in the management of obesity.

Conclusion:

Food preferences are acquired in childhood and sound nutritional practices should be established in childhood to prevent lifestyle disorders and premature aging. Though CR is a known and preferred non-pharmacological intervention in the management of obesity, its implemention has not been explored and evaluated extensively. This is a vital area that needs scientific research as the goals of obesity managements are no longer just weight loss through dietary restrictions. An interdisciplinary method to lifestyle modification in the management of adolescent obesity addressing all physiological and psychosocial aspects is recommended.

Protective Association of Single Nucleotide Polymorphisms rs1861868-FTO and rs7975232-VDR and Obesity in Saudi Females

Background

Obesity is a major health threat worldwide. It predisposes individuals to diabetes, cardiovascular complications, and cancer. Genetic and environmental factors are responsible for the increasing incidence of obesity. In this study, we investigated the genetic factors associated with obesity in young Saudi women.

Subjects and Methods

In this cross-sectional study, 131 young Saudi female students were recruited. Body mass index (BMI), waist–hip ratio, blood glucose, triglyceride, cholesterol, HDL, LDL, and vitamin D3 levels of the subjects were determined. Twelve SNPs of different genes that showed a correlation with obesity in different population were tested, namely GNPDA2 (rs10938397), TCF7L2 (rs10885409), FTO (rs1477196), ADIPOQ (rs1501299), MC4R (rs17782313), ABCA1 (rs1800977), FTO (rs1861868), VDR (rs2228570), VDR (rs731236), VDR (rs7975232), ADIPOQ (rs266729), and PFPK (rs6602024). Student’s t-test was conducted for all parameters. Pearson correlation was performed to identify the correlated variables. The frequencies of different risk alleles were determined by direct counting of the test allele divided by the total number of alleles and compared.

Results

Only two SNPs, rs1861868 of FTO and rs7975232 of VDR, of the twelve tested SNPs showed significant protective associations with the BMI with odds ratio 0.3886 (0.1761–0.8572); p 0.0192 and odds ratio 0.4563 (0.2343–0.8888); p 0.0211, respectively.

Conclusion

The current study showed that minor alleles, “T” of FTO and “A” of VDR, might be protective factors against increased BMI in young Saudi female subjects. To elucidate this association, further studies with larger sample size involving both sexes are required.

Modelling the on-going natural selection of educational attainment in contemporary societies

There has been substantial increase in education attainment (EA) in both developing and developed countries over the past century. I present a simulation model to examine the potential evolutionary trajectories of EA under current selective pressure in western populations. With the assumption that EA is negatively correlated with fitness and has both a genetic component and a cultural component, I show that when prestige-biased transmission of the EA (i.e. people with more education are more likely to be copied) is present, the phenotype of EA is likely to keep increasing in the short term, yet the genetic component of EA may undergo a constant decline and become the limiting factor in further phenotypic increase.

Nutritional genomics, inflammation and obesity

The Human Genome Project has significantly broadened our understanding of the molecular aspects regulating the homeostasis and the pathophysiology of different clinical conditions. Consequently, the field of nutrition has been strongly influenced by such improvements in knowledge - especially for determining how nutrients act at the molecular level in different conditions, such as obesity, type 2 diabetes, cardiovascular disease, and cancer. In this manner, characterizing how the genome influences the diet and vice-versa provides insights about the molecular mechanisms involved in chronic inflammation-related diseases. Therefore, the present review aims to discuss the potential application of Nutritional Genomics to modulate obesity-related inflammatory responses. Arch Endocrinol Metab. 2020;64(3):205-22.

Polygenic Score for Body Mass Index Is Associated with Disordered Eating in a General Population Cohort

Background: Disordered eating (DE) is common and is associated with body mass index (BMI). We investigated whether genetic variants for BMI were associated with DE. Methods: BMI polygenic scores (PGS) were calculated for participants of the Avon Longitudinal Study of Parents and Children (ALSPAC; N = 8654) and their association with DE tested. Data on DE behaviors (e.g., binge eating and compensatory behaviors) were collected at ages 14, 16, 18 years, and DE cognitions (e.g., body dissatisfaction) at 14 years. Mediation analyses determined whether BMI mediated the association between the BMI-PGS and DE. Results: The BMI-PGS was positively associated with fasting (OR = 1.42, 95% CI = 1.25, 1.61), binge eating (OR = 1.28, 95% CI = 1.12, 1.46), purging (OR = 1.20, 95% CI = 1.02, 1.42), body dissatisfaction (Beta = 0.99, 95% CI = 0.77, 1.22), restrained eating (Beta = 0.14, 95% CI = 0.10, 1.17), emotional eating (Beta = 0.21, 95% CI = 0.052, 0.38), and negatively associated with thin ideal internalization (Beta = −0.15, 95% CI = −0.23, −0.07) and external eating (Beta = −0.19, 95% CI = −0.30, −0.09). These associations were mainly mediated by BMI. Conclusions: Genetic variants associated with BMI are also associated with DE. This association was mediated through BMI suggesting that weight potentially sits on the pathway from genetic liability to DE.

The effect of berberine supplementation on obesity indices: A dose- response meta-analysis and systematic review of randomized controlled trials

BACKGROUND

and purpose: Clinical studies investigating the effects of berberine supplementation on anthropometric indices in humans have generated inconsistent results. Thus, the objective of this systematic review and meta-analysis was to clarify the effects of berberine supplementation on obesity indices in human subjects.

METHODS

Several online medical databases were systematically searched up to February 2019. All clinical trials exploring the effects of berberine supplementation on indices of obesity were included. The combined weighted mean difference (WMD) of eligible studies was assessed using a random-effects model. We evaluated publication bias by using the Egger's test.

RESULTS

Overall, 10 studies were included. The combined outcomes suggested a significant influence of berberine administration on body mass index (BMI) (WMD: -0.29 kg/m², 95% CI: -0.51 to -0.08, p = 0.006) and waist circumference (WC) (WMD: -2.75 cm, 95% CI: -4.88 to -0.62, p = 0.01). However, berberine supplementation yielded no significant decline in body weight (BW) (WMD: -0.11 kg, 95% CI: -0.99 to 0.76, p = 0.79). Following the dose-response evaluation, berberine intake was found to significantly reduce BMI (r = -0.02) and WC (r = -0.72) based on treatment duration.

CONCLUSION

The results of the current study support the use of berberine supplementation for the improvement of obesity indices.

Chronic Adipose Tissue Inflammation Linking Obesity to Insulin Resistance and Type 2 Diabetes

Obesity is one of the major health burdens of the 21st century as it contributes to the growing prevalence of its related comorbidities, including insulin resistance and type 2 diabetes. Growing evidence suggests a critical role for overnutrition in the development of low-grade inflammation. Specifically, chronic inflammation in adipose tissue is considered a crucial risk factor for the development of insulin resistance and type 2 diabetes in obese individuals. The triggers for adipose tissue inflammation are still poorly defined. However, obesity-induced adipose tissue expansion provides a plethora of intrinsic signals (e.g., adipocyte death, hypoxia, and mechanical stress) capable of initiating the inflammatory response. Immune dysregulation in adipose tissue of obese subjects results in a chronic low-grade inflammation characterized by increased infiltration and activation of innate and adaptive immune cells. Macrophages are the most abundant innate immune cells infiltrating and accumulating into adipose tissue of obese individuals; they constitute up to 40% of all adipose tissue cells in obesity. In obesity, adipose tissue macrophages are polarized into pro-inflammatory M1 macrophages and secrete many pro-inflammatory cytokines capable of impairing insulin signaling, therefore promoting the progression of insulin resistance. Besides macrophages, many other immune cells (e.g., dendritic cells, mast cells, neutrophils, B cells, and T cells) reside in adipose tissue during obesity, playing a key role in the development of adipose tissue inflammation and insulin resistance. The association of obesity, adipose tissue inflammation, and metabolic diseases makes inflammatory pathways an appealing target for the treatment of obesity-related metabolic complications. In this review, we summarize the molecular mechanisms responsible for the obesity-induced adipose tissue inflammation and progression toward obesity-associated comorbidities and highlight the current therapeutic strategies.

Epigenetic and Transcriptomic Characterization of Pure Adipocyte Fractions From Obese Pigs Identifies Candidate Pathways Controlling Metabolism

Reprogramming of adipocyte function in obesity is implicated in metabolic disorders like type 2 diabetes. Here, we used the pig, an animal model sharing many physiological and pathophysiological similarities with humans, to perform in-depth epigenomic and transcriptomic characterization of pure adipocyte fractions. Using a combined DNA methylation capture sequencing and Reduced Representation bisulfite sequencing (RRBS) strategy in 11 lean and 12 obese pigs, we identified in 3529 differentially methylated regions (DMRs) located at close proximity to-, or within genes in the adipocytes. By sequencing of the transcriptome from the same fraction of isolated adipocytes, we identified 276 differentially expressed transcripts with at least one or more DMR. These transcripts were over-represented in gene pathways related to MAPK, metabolic and insulin signaling. Using a candidate gene approach, we further characterized 13 genes potentially regulated by DNA methylation and identified putative transcription factor binding sites that could be affected by the differential methylation in obesity. Our data constitute a valuable resource for further investigations aiming to delineate the epigenetic etiology of metabolic disorders.

Relationship between psychological stress and metabolism in morbidly obese individuals

BACKGROUND

Despite evidence for a bidirectional relationship between obesity and stress-related mental disorders, the general relationship between psychological stress and metabolism is still controversial. Only few studies have addressed this relationship in morbidly obese individuals.

METHODS

The present study investigated the relationship between psychological distress, health-related quality of life (HRQL), eating behavior, negative emotions and body mass index (BMI), body composition and biomedical parameters of metabolism in an adult sample of 123 (94 females) morbidly obese individuals.

RESULTS

No significant relationship was found between psychological distress and BMI, body composition or any of the parameters of metabolism; however, there was a strong and robust association between HRQL in the physical domain and BMI, body composition and several biomedical parameters of sugar and fat metabolism. The results also showed an interesting dissociation in the relationship between BMI and HRQL in the physical and psychology domains. Only little evidence was found for a relationship between eating behavior (e.g. restraint) or negative emotions (e.g. anger) and BMI, body composition and parameters of metabolism. There was, however, a significant gender difference in restraint eating. Other commonly reported gender differences in BMI, body composition, fat metabolism and liver values were also observed in this sample of morbidly obese individuals.

CONCLUSION

Results from the present study highlight the relationship between HRQL in the physical domain and metabolism. Implications of these findings for weight loss treatment are discussed, emphasizing HRQL as an important treatment goal and the need for long-term psychological monitoring.