A war on obesity, not the obese

Impact of spinach thylakoid extract-induced 12-week high-intensity functional training on specific adipokines in obese males

BACKGROUND

Obesity presents multifarious etiopathologies with its management being a global challenge. This article presents the first ever report on the impact of spinach thylakoid extract-induced high-intensity functional training (HIFT) on obesity management via regulating the levels of novel adipokine, C1q/TNF-related Protein-12 (CTRP-12), furin, and Krüppel-like factor 15 (KLF-15).

METHODS

Sixty-eight obese male subjects were randomly divided into four groups: control group (CG), supplement group (SG), training group (TG), and the combined training and supplement group (TSG). After initial assessments of all groups, the training group commenced a twelve-week HIFT using the CrossFit program (comprising of three training sessions per week, each lasting 30 min). Eligible candidates were randomly assigned to either receive thylakoid-rich spinach extract (5 g per day) or a matching placebo (5 g per day of corn starch, 30 min before lunch) for a total duration of 12 weeks. All required data and investigations were collected at 48 h pre- and post-training.

RESULTS

The results indicated a substantial correlation between exercise and the time of KLF-15, furin, and CTRP-12 demonstrating effect sizes of 0.3, 0.7, and 0.6, respectively. Additionally, the training and supplementation group (TSG) exhibited a substantial decrease in low-density lipoprotein (LDL), total cholesterol (TC), and triglyceride (TG) levels (p < 0.0001). Concurrently, there was a significant increase in high-density lipoprotein-cholesterol (HDL-C) levels (p = 0.0001). Furthermore, a notable difference between the groups emerged in HDL, LDL, TC, and TG levels, supported by effect sizes of 0.73, 0.86, 0.96, and 0.89, respectively (p < 0.05).

CONCLUSION

The study offered novel insights into the management of obesity using supplements induced by spinach-derived thylakoid extract during a 12-week HIFT program. The proposed combination intervention may reverse obesity-induced insulin resistance and metabolic dysfunctions by positive regulation of CTRP-12/adipolin and KLF15 and simultaneous suppression of furin levels.

Caffeine: a potential mechanism for anti-obesity

Obesity refers to the excessive accumulation of fat caused by a long-term imbalance between energy intake (EI) and energy expenditure (EE). Over recent years, obesity has become a major public health challenge. Caffeine is a natural product that has been demonstrated to exert anti-obesity effects; however, the mechanisms responsible for the effect of caffeine on weight loss have yet to be fully elucidated. Most obesity-related deaths are due to cardiovascular disease. Recent research has demonstrated that caffeine can reduce the risk of death from cardiovascular disease; thus, it can be hypothesized that caffeine may represent a new therapeutic agent for weight loss. In this review, we synthesize data arising from clinical and animal studies over the last decade and discuss the potential mechanisms by which caffeine may induce weight loss, focusing particularly on increasing energy consumption, suppressing appetite, altering lipid metabolism, and influencing the gut microbiota. Finally, we summarize the major challenges associated with caffeine and anti-obesity research and highlight possible directions for future research and development.

The melanocortin-4 receptor pathway and the emergence of precision medicine in obesity management

Over the past few decades, there has been a global surge in the prevalence of obesity, rendering it a globally recognized epidemic. Contrary to simply being a medical condition, obesity is an intricate disease with a multifactorial aetiology. Understanding the precise cause of obesity remains a challenge; nevertheless, there seems to be a complex interplay among biological, psychosocial and behavioural factors. Studies on the genetic factors of obesity have revealed several pathways in the brain that play a crucial role in food intake regulation. The best characterized pathway, thus far, is the leptin-melanocortin pathway, from which disruptions are responsible for the majority of monogenic obesity disorders. The effectiveness of conservative lifestyle interventions in addressing monogenic obesity has been limited. Therefore, it is crucial to complement the management strategy with pharmacological and surgical options. Emphasis has been placed on developing drugs aimed at replacing the absent signals, with the goal of restoring the pathway. In both monogenic and polygenic forms of obesity, outcomes differ across various interventions, likely due to the multifaceted nature of the disease. This underscores the need to explore alternative therapeutic strategies that can mitigate this heterogeneity. Precision medicine can be regarded as a powerful tool that can address this concern, as it values the understanding of the underlying abnormality triggering the disease and provides a tailored treatment accordingly. This would assist in optimizing outcomes of the current therapeutic approaches and even aid in the development of novel treatments capable of more effectively managing the global obesity epidemic.

Integrative neurocircuits that control metabolism and food intake

Systemic metabolism has to be constantly adjusted to the variance of food intake and even be prepared for anticipated changes in nutrient availability. Therefore, the brain integrates multiple homeostatic signals with numerous cues that predict future deviations in energy supply. Recently, our understanding of the neural pathways underlying these regulatory principles-as well as their convergence in the hypothalamus as the key coordinator of food intake, energy expenditure, and glucose metabolism-have been revealed. These advances have changed our view of brain-dependent control of metabolic physiology. In this Review, we discuss new concepts about how alterations in these pathways contribute to the development of prevalent metabolic diseases such as obesity and type 2 diabetes mellitus and how this emerging knowledge may provide new targets for their treatment.

Gut hormone co-agonists for the treatment of obesity: from bench to bedside

The discovery and development of so-called gut hormone co-agonists as a new class of drugs for the treatment of diabetes and obesity is considered a transformative breakthrough in the field. Combining action profiles of multiple gastrointestinal hormones within a single molecule, these novel therapeutics achieve synergistic metabolic benefits. The first such compound, reported in 2009, was based on balanced co-agonism at glucagon and glucagon-like peptide-1 (GLP-1) receptors. Today, several classes of gut hormone co-agonists are in development and advancing through clinical trials, including dual GLP-1-glucose-dependent insulinotropic polypeptide (GIP) co-agonists (first described in 2013), and triple GIP-GLP-1-glucagon co-agonists (initially designed in 2015). The GLP-1-GIP co-agonist tirzepatide was approved in 2022 by the US Food and Drug Administration for the treatment of type 2 diabetes, providing superior HbA1c reductions compared to basal insulin or selective GLP-1 receptor agonists. Tirzepatide also achieved unprecedented weight loss of up to 22.5%-similar to results achieved with some types of bariatric surgery-in non-diabetic individuals with obesity. In this Perspective, we summarize the discovery, development, mechanisms of action and clinical efficacy of the different types of gut hormone co-agonists, and discuss potential challenges, limitations and future developments.

Real-World Intake of Dietary Sugars Is Associated with Reduced Cortisol Reactivity Following an Acute Physiological Stressor

There is increasing academic and clinical interest in understanding the nature of the relation between diet and response to stress exposure as a risk factor for mental illness. Cross-species evidence shows that conditions of chronic and acute stress increase the intake of, and preference for, caloric-dense palatable foods, a phenomenon thought to be explained by the mitigating effects of comfort foods on the activity of the stress-response network. It is largely unknown whether and how real-world dietary intake of saturated fat and sugars impacts stress responsivity in humans. Therefore, here we examined whether real-world dietary intake of saturated fat and sugars predicted salivary cortisol reactivity following an acute physiological stressor. Multilevel modelling of four salivary cortisol measures collected up to 65 min after the stressor on 54 participants (18-49 years old) were analyzed using a quadratic growth curve model. Sugar intake significantly predicted a weaker cortisol response following the Cold Pressor Test (CPT) controlling for BMI and gender, revealing an inhibitory effect of caloric-dense diets on cortisol reactivity to stress. As the consumption of sugar rose individuals had lower post-stressor cortisol levels, a smaller rate of increase in cortisol 20 and 35 min after the CPT, a lower cortisol peak, and an overall weaker quadratic effect. These observations add to a growing body of evidence reporting suppressive effects of high-energy foods on stress-associated glucocorticoids reactivity and are consistent with the comfort food hypothesis, where people are seen as motivated to eat palatable foods to alleviate the detrimental repercussions of stressor exposure.

Secreted EMC10 is upregulated in human obesity and its neutralizing antibody prevents diet-induced obesity in mice

Secreted isoform of endoplasmic reticulum membrane complex subunit 10 (scEMC10) is a poorly characterized secreted protein of largely unknown physiological function. Here we demonstrate that scEMC10 is upregulated in people with obesity and is positively associated with insulin resistance. Consistent with a causal role for scEMC10 in obesity, Emc10-/- mice are resistant to diet-induced obesity due to an increase in energy expenditure, while scEMC10 overexpression decreases energy expenditure, thus promoting obesity in mouse. Furthermore, neutralization of circulating scEMC10 using a monoclonal antibody reduces body weight and enhances insulin sensitivity in obese mice. Mechanistically, we provide evidence that scEMC10 can be transported into cells where it binds to the catalytic subunit of PKA and inhibits its stimulatory action on CREB while ablation of EMC10 promotes thermogenesis in adipocytes via activation of the PKA signalling pathway and its downstream targets. Taken together, our data identify scEMC10 as a circulating inhibitor of thermogenesis and a potential therapeutic target for obesity and its cardiometabolic complications.

Revisioning Obesity in Health Care Practice and Research: New Perspectives on the Role of Body Temperature

Obesity is a leading health problem in the United States and globally. Relatively few people with obesity achieve long-term weight control, suggesting that obesity and resistance to weight change represent functional adaption of energy homeostasis to the environment. The purpose of this article is to synthesize the literature regarding the relationship between environmental temperature and body weight and fat mass to provide a new explanation of obesity as a problem of maintaining core body temperature. Chronic exposure to cool environmental temperatures likely contributed to the obesity epidemic, and passive whole-body warming may be a promising intervention for weight control.

Diet-Induced Metabolic Dysfunction of Hypothalamic Nutrient Sensing in Rodents

A sedentary lifestyle and excessive nutrient intake resulting from the consumption of high-fat and calorie-rich diets are environmental factors contributing to the rapid growth of the current pandemic of type 2 diabetes mellitus (DM2). Fasting hyperglycemia, an established hallmark of DM2, is caused by excessive production of glucose by the liver, resulting in the inability of insulin to suppress endogenous glucose production. To prevent inappropriate elevations of circulating glucose resulting from changes in nutrient availability, mammals rely on complex mechanisms for continuously detecting these changes and to respond to them with metabolic adaptations designed to modulate glucose output. The mediobasal hypothalamus (MBH) is the key center where nutritional cues are detected and appropriate modulatory responses are integrated. However, certain environmental factors may have a negative impact on these adaptive responses. For example, consumption of a diet enriched in saturated fat in rodents resulted in the development of a metabolic defect that attenuated these nutrient sensing mechanisms, rendering the animals prone to developing hyperglycemia. Thus, high-fat feeding leads to a state of “metabolic disability” in which animals’ glucoregulatory responses fail. We postulate that the chronic faltering of the hypothalamic glucoregulatory mechanisms contributes to the development of metabolic disease.

Anti-obesity drug discovery: advances and challenges

Enormous progress has been made in the last half-century in the management of diseases closely integrated with excess body weight, such as hypertension, adult-onset diabetes and elevated cholesterol. However, the treatment of obesity itself has proven largely resistant to therapy, with anti-obesity medications (AOMs) often delivering insufficient efficacy and dubious safety. Here, we provide an overview of the history of AOM development, focusing on lessons learned and ongoing obstacles. Recent advances, including increased understanding of the molecular gut-brain communication, are inspiring the pursuit of next-generation AOMs that appear capable of safely achieving sizeable and sustained body weight loss.

A study of leptin and its gene 2548 G/A Rs7799039 single-nucleotide polymorphisms in Egyptian children: A single-center experience

BACKGROUND/OBJECTIVES

The pathophysiology of obesity is multifactorial, including genetic and environmental factors. Previous studies had highlighted the association of the leptin gene/receptor with obesity. We aimed to study the leptin gene rs7799039 single nucleotide polymorphism (SNP) in children, and its association with the children's characteristics.

METHODS

A cross-sectional analytic study that included 143 children with obesity (cases) and a comparable group of 86 lean children as controls. The anthropometric measures, blood pressure, and biochemical testing were done for all participants. The real-time polymerase chain reaction was used to detect rs7799039 SNP variant alleles and ELISA for leptin level assessment.

RESULTS

The distribution of rs7799039 SNPs genotypes GG/GA/AA was comparable between both groups. Testing children regardless of their body mass index showed that the abnormalities in blood pressure, lipids values, insulin resistance, and hepatic insulin sensitivity were significantly associated with increased leptin levels. Among cases, the abnormal metabolic status was associated with higher leptin levels.

CONCLUSIONS

The genotype' distribution of leptin gene rs7799039 SNP was similar in both children with obesity and those with normal-weight. The high blood pressure, abnormal lipid profile, and metabolic disturbances, were significantly associated with higher leptin levels and not with leptin gene rs7799039 SNP.

MECHANISMS IN ENDOCRINOLOGY: The gut-brain axis: regulating energy balance independent of food intake

Obesity is a global pandemic with a large health and economic burden worldwide. Bodyweight is regulated by the ability of the CNS, and especially the hypothalamus, to orchestrate the function of peripheral organs that play a key role in metabolism. Gut hormones play a fundamental role in the regulation of energy balance, as they modulate not only feeding behavior but also energy expenditure and nutrient partitioning. This review examines the recent discoveries about hormones produced in the stomach and gut, which have been reported to regulate food intake and energy expenditure in preclinical models. Some of these hormones act on the hypothalamus to modulate thermogenesis and adiposity in a food intake-independent fashion. Finally, the association of these gut hormones to eating, energy expenditure, and weight loss after bariatric surgery in humans is discussed.

A multitarget angiogenesis inhibitor, CTT peptide-endostatin mimic-kringle 5, prevents diet-induced obesity

Adipose tissue vasculature has been considered an attractive target for prevention and treatment of obesity. AARP (CTT peptide-endostatin mimic-kringle 5) is a novel multitarget fusion protein against tumor angiogenesis. This study aimed to examine the effects of AARP on diet-induced obesity and its possible molecular mechanism. Treatment with AARP markedly prevented weight gains, improved metabolic disturbances, and decreased adipose tissue angiogenesis in diet-induced obese mice without noticeable toxicities. In addition to its potent antiangiogenic and MMP-2/9 inhibitory activities, AARP administration also significantly increased energy expenditure, influenced the metabolic and angiogenic gene expression profiles, and attenuated obesity-induced inflammation, demonstrating its systemic beneficial effects. Importantly, AARP exhibited no effect on mice fed with standard normal mouse diet. Furthermore, the AARP-treated HFD-fed mice experienced a significant increase in lifespan during the posttreatment observation period, compared with untreated HFD-fed mice. Our results suggest that AARP might be pharmacologically useful for treatment of obesity or obesity-related metabolic disorders in humans. KEY MESSAGES: What is already known • More effective and safe therapies for obesity are in urgent need. • AARP is a novel multitarget fusion protein against tumor angiogenesis. What this study adds • AARP prevents obesity, improves metabolic disorders in mice fed high-fat diet. • AARP increases energy expenditure, decreases adipose tissue angiogenesis, and increases lifespan. • AARP is well tolerated and exhibits no observable toxicity. Clinical significance • AARP may be a promising therapeutic agent against obesity or obesity-related metabolic disturbances.

Progress in the development of human carbonic anhydrase inhibitors and their pharmacological applications: Where are we today?

Carbonic anhydrases (CAs, EC 4.2.1.1) are widely distributed metalloenzymes in both prokaryotes and eukaryotes. They efficiently catalyze the reversible hydration of carbon dioxide to bicarbonate and H⁺  ions and play a crucial role in regulating many physiological processes. CAs are well-studied drug target for various disorders such as glaucoma, epilepsy, sleep apnea, and high altitude sickness. In the past decades, a large category of diverse families of CA inhibitors (CAIs) have been developed and many of them showed effective inhibition toward specific isoforms, and effectiveness in pathological conditions in preclinical and clinical settings. The discovery of isoform-selective CAIs in the last decade led to diminished side effects associated with off-target isoforms inhibition. The many new classes of such compounds will be discussed in the review, together with strategies for their development. Pharmacological advances of the newly emerged CAIs in diseases not usually associated with CA inhibition (neuropathic pain, arthritis, cerebral ischemia, and cancer) will also be discussed.

FTO variants are associated with ANGPTL4 abundances and correlated with body weight reduction after bariatric surgery

BACKGROUND

The FTO (fat mass- and obesity-associated) gene variant is an established obesity-susceptibility locus. FTO protein is a nucleic acid demethylase and FTO genetic variants form long-range functional connections with IRX3, which regulates fat mass and metabolism in humans. From our previous results, we found FTO regulates the metabolism of triglyceride in adipocytes through demethylating Angptl4 (angiopoietin-like protein 4) mRNA in mice. We hypothesized that the FTO genetic variants regulate ANGPTL4 abundances in human adipose tissues and affect the outcome after bariatric surgery.

METHODS AND RESULTS

We recruited 188 obesity subjects with body mass indices (BMI)>35kg/m² and 102 non-obese subjects with BMI<30kg/m² from the OCEAN registry between 2011 and 2014. The distribution of FTO variants rs9939609 among participates was 73.79% TT, 23.79% AT, and 2.41% AA. The subjects with FTO variants AA or AT were correlated with higher BMI than those with FTO variants TT. The serum ANGPTL4 levels were significantly higher in obese subjects and positively correlated with the presence of FTO AA or AT haplotype. Of these participates, 84 obese subjects underwent bariatric surgery and adipose Angptl4 expressions were analyzed. The adipose Angptl4 mRNA levels and protein abundances were correlated with FTO AA or AT haplotype. The magnitude of excess body weight reduction 2 years after bariatric surgery was correlated with the adipose ANGPTL4 protein levels.

CONCLUSION

Adipose ANGPTL4 abundances were affected by the presence of FTO obesity risk haplotype and correlated with excess weight loss percentage after bariatric surgery. These data signify the critical role of FTO variants and adipose ANGPTL4 in fatty acid metabolism and bariatric outcomes in humans.

Regulation of adipocyte thermogenesis: mechanisms controlling obesity

Adipocyte biology has been intensely researched in recent years due to the emergence of obesity as a serious global health concern and because of the realization that adipose tissue is more than simply a cell type that stores and releases lipids. The plasticity of adipose tissues, to rapidly adapt to altered physiological states of energy demand, is under neuronal and endocrine control. The capacity for white adipocytes to store chemical energy in lipid droplets is key for protecting other organs from the toxic effects of ectopic lipid deposition. In contrast, thermogenic (brown and beige) adipocytes combust macronutrients to generate heat. The thermogenic activity of adipocytes allows them to protect themselves and other tissues from lipid overaccumulation. Advances in brown fat biology have uncovered key molecular players involved in adipocyte determination, differentiation, and thermogenic activation. It is now, well appreciated that three distinct adipocyte types exist: white, beige, and brown. Moreover, functional differences are present within adipocyte subtypes located in anatomically distinct locations. Adding to this complexity is the recent realization from single-cell sequencing studies that adipocyte progenitors are also heterogeneous. Understanding the molecular details of how to increase the number of thermogenic fat cells and their activation may delineate some of the pathophysiological basis of obesity and obesity-related diseases. Here, we review recent advances that have extended our understanding of the central role that adipose tissue plays in energy balance and the mechanisms that control their amount and function.

The effects of growth hormone on adipose tissue: old observations, new mechanisms

The ability of growth hormone (GH) to induce adipose tissue lipolysis has been known for over five decades; however, the molecular mechanisms that mediate this effect and the ability of GH to inhibit insulin-stimulated glucose uptake have scarcely been documented. In this same time frame, our understanding of adipose tissue has evolved to reveal a complex structure with distinct types of adipocyte, depot-specific differences, a biologically significant extracellular matrix and important endocrine properties mediated by adipokines. All these aforementioned features, in turn, can influence lipolysis. In this Review, we provide a historical and current overview of the lipolytic effect of GH in humans, mice and cultured cells. More globally, we explain lipolysis in terms of GH-induced intracellular signalling and its effect on obesity, insulin resistance and lipotoxicity. In this regard, findings that define molecular mechanisms by which GH induces lipolysis are described. Finally, data are presented for the differential effect of GH on specific adipose tissue depots and on distinct classes of metabolically active adipocytes. Together, these cellular, animal and human studies reveal novel cellular phenotypes and molecular pathways regulating the metabolic effects of GH on adipose tissue.

Leptin and the endocrine control of energy balance

The discovery of leptin changed the view of adipose tissue from that of a passive vessel that stores fat to that of a dynamic endocrine organ that actively regulates behaviour and metabolism. Secreted by adipose tissue, leptin functions as an afferent signal in a negative feedback loop, acting primarily on neurons in the hypothalamus and regulating feeding and many other functions. The leptin endocrine system serves a critical evolutionary function by maintaining the relative constancy of adipose tissue mass, thereby protecting individuals from the risks associated with being too thin (starvation and infertility) or too obese (predation). In this Review, the biology of leptin is summarized, and a conceptual framework is established for studying the pathogenesis of obesity, which, analogously to diabetes, can result from either leptin hyposecretion or leptin resistance. Herein, these two states are distinguished with the terms 'type 1 obesity' and 'type 2 obesity': type 1 obesity describes a subset of obese individuals with low endogenous plasma leptin levels who respond to leptin therapy, whereas type 2 obesity describes most obese individuals, who are leptin resistant but might respond to leptin therapy in combination with other drugs, such as leptin sensitizers.

Possible involvement of 4-hydroxy-2-nonenal in the pathogenesis of leptin resistance in obesity

Insensitivity to the antiobesity hormone, leptin, has been suggested to be involved in the pathogenesis of obesity. However, the pathological mechanisms underlying the development of leptin resistance are not well-understood. This study aimed to examine the pathological mechanisms of leptin resistance in obesity. In the present study, we found that 4-hydroxy-2-nonenal (4-HNE), an aldehyde, may be involved in the development of leptin resistance. The SH-SY5Y-Ob-Rb human neuroblastoma cell line, transfected to express the Ob-Rb leptin receptor stably, was treated with 4-HNE, and leptin-induced signal transduction was analyzed. We found that 4-HNE dose- and time-dependently inhibited leptin-induced signal transducer and activator of transcription 3 (STAT3) phosphorylation, a major antiobesity signal of leptin. On the other hand, 4-HNE did not affect tyrosine phosphorylation of broad cellular proteins, suggesting that the inhibitory effect may be selective to leptin signaling. Mechanistically, 4-HNE induced the eukaryotic initiation factor 2α-CCAAT/enhancer-binding protein homologous protein arm of endoplasmic reticulum stress signaling, which may be involved in the pathogenesis of leptin resistance. Overall, these results suggest that 4-HNE may partly affect endoplasmic reticulum stress-induced unfolded protein response signaling and may be involved in the pathogenesis of leptin resistance.

Lack of Hypothalamus Polysialylation Inducibility Correlates With Maladaptive Eating Behaviors and Predisposition to Obesity

High variability exists in individual susceptibility to develop overweight in an obesogenic environment and the biological underpinnings of this heterogeneity are poorly understood. In this brief report, we show in mice that the vulnerability to diet-induced obesity is associated with low level of polysialic acid-neural cell adhesion molecule (PSA-NCAM), a factor of neural plasticity, in the hypothalamus. As we previously shown that reduction of hypothalamic PSA-NCAM is sufficient to alter energy homeostasis and promote fat storage under hypercaloric pressure, inter-individual variability in hypothalamic PSA-NCAM might account for the vulnerability to diet-induced obesity. These data support the concept that reduced plasticity in brain circuits that control appetite, metabolism and body weight confers risk for eating disorders and obesity.

Atf3 induction is a therapeutic target for obesity and metabolic diseases

Activating transcription factor 3 (Atf3) has been previously demonstrated to impact obesity and metabolism. However, a metabolic role of Atf3 in mice remains debatable. We investigated the role of Atf3 in mice and further investigated Atf3 expression as a therapeutic target for obesity and metabolic diseases. Atf3 knockout (KO) mice fed with a high fat diet (HFD) aggravated weight gain and impaired glucose metabolism compared to littermate control wild type (WT) mice. Atf3 KO aged mice fed with a chow diet (CD) for longer than 10 months also displayed increased body weight and fat mass compared to WT aged mice. We also assessed requirements of Atf3 in a phytochemical mediated anti-obese effect. Effect of sulfuretin, a previously known phytochemical Atf3 inducer, in counteracting weight gain and improving glucose tolerance was almost completely abolished in the absence of Atf3, indicating that Atf3 induction can be a molecular target for preventing obesity and metabolic diseases. We further identified other Atf3 small molecule inducers that exhibit inhibitory effects on lipid accumulation in adipocytes. These data highlight the role of Atf3 in obesity and further suggest the use of chemical Atf3 inducers for prevention of obesity and metabolic diseases.

Response gene to complement 32 suppresses adipose tissue thermogenic genes through inhibiting β3-adrenergic receptor/mTORC1 signaling

Our previous studies have shown that response gene to complement (RGC)-32 deficiency (Rgc32^-/-) protects mice from diet-induced obesity and increases thermogenic gene expression in adipose tissues. However, the underlying mechanisms by which RGC-32 regulates thermogenic gene expression remain to be determined. In the present study, RGC-32 expression in white adipose tissue (WAT) was suppressed during cold exposure-induced WAT browning. Rgc32^-/- significantly increased thermogenic gene expression in the differentiated stromal vascular fraction (SVF) of inguinal (i)WAT and interscapular brown adipose tissue (BAT). Rgc32^-/- and cold exposure regulated a common set of genes in iWAT, as shown by RNA sequencing data. Pathway enrichment analyses showed that Rgc32^-/- down-regulated PI3K/Akt signaling-related genes. Akt phosphorylation was also consistently decreased in Rgc32^-/- iWAT, which led to an increase in β3-adrenergic receptor (β3-AR) expression and subsequent activation of mammalian target of rapamycin complex (mTORC)-1. β3-AR antagonist SR 59230A and mTORC1 inhibitor rapamycin blocked Rgc32^-/--induced thermogenic gene expression in both iWAT and interscapular BAT. These results indicate that RGC-32 suppresses adipose tissue thermogenic gene expression through down-regulation of β3-AR expression and mTORC1 activity via a PI3K/Akt-dependent mechanism.-Chen, S., Mei, X., Yin, A., Yin, H., Cui, X.-B., Chen, S.-Y. Response gene to complement 32 suppresses adipose tissue thermogenic genes through inhibiting β3-adrenergic receptor/mTORC1 signaling.

Differential response of rat strains to obesogenic diets underlines the importance of genetic makeup of an individual towards obesity

Obesity, a multifactorial disorder, results from a chronic imbalance of energy intake vs. expenditure. Apart from excessive consumption of high calorie diet, genetic predisposition also seems to be equally important for the development of obesity. However, the role of genetic predisposition in the etiology of obesity has not been clearly delineated. The present study addresses this problem by selecting three rat strains (WNIN, F-344, SD) with different genetic backgrounds and exposing them to high calorie diets. Rat strains were fed HF, HS, and HFS diets and assessed for physical, metabolic, biochemical, inflammatory responses, and mRNA expression. Under these conditions: significant increase in body weight, visceral adiposity, oxidative stress and systemic pro-inflammatory status; the hallmarks of central obesity were noticed only in WNIN. Further, they developed altered glucose and lipid homeostasis by exhibiting insulin resistance, impaired glucose tolerance, dyslipidemia and fatty liver condition. The present study demonstrates that WNIN is more prone to develop obesity and associated co-morbidities under high calorie environment. It thus underlines the cumulative role of genetics (nature) and diet (nurture) towards the development of obesity, which is critical for understanding this epidemic and devising new strategies to control and manage this modern malady.

The combined effect of Sango sprout juice and caloric restriction on metabolic disorders and gut microbiota composition in an obesity model

The main purpose of this study was to compare the benefits of SSJ supplementation in obese rats with those achieved only by switching the alimentary regimen from high-fat (HFD) to the regular one (RD) in liver, ileum and prostate. Furthermore, changings in caecal chime microbiota were investigated. SSJ was administered to rats in combination with a RD (HFD-RD + SSJ). The switch from HFD to RD led to a weight loss of almost 9.8 g, and the total cholesterol was found to be significantly lower. In the HFD-RD + SSJ group, all values were improved compared with the HFD control, and the weight decrement was higher (-23.29 g) with respect to HFD-RD. HFD led to a widespread increment of oxidative stress (OS) markers in liver, ileum and prostate. SSJ has shown to improve the results achieved by the suspension of HFD and it has proven effective wherever the only switch in diet regimen failed.

The impact of marriage and parenthood on male body mass index: Static and dynamic effects

RATIONALE

Numerous cross-sectional studies investigated the link between marital status and BMI in the context of competing social science theories (marriage market, marriage selection, marriage protection and social obligation), frequently offering conflicting theoretical predictions and conflicting empirical findings.

OBJECTIVE

This study analysed the effects of marriage, divorce, pregnancy, and parenthood on male BMI in a longitudinal setting, avoiding the estimation bias of cross-sectional studies and allowing for an analysis of BMI fluctuation over time and the dynamic effects of these events.

METHOD

Using the Panel Study of Income Dynamics 1999-2013 dataset (N = 8729), this study was the first to employ a dynamic panel-data estimation to examine the static and dynamic effects of marriage, divorce, and fatherhood on male BMI.

RESULTS

The study showed that married men have higher BMI, but marital status changes largely drove this static effect, namely, an increase in BMI in the period following marriage, and a decrease in BMI preceding and following divorce.

CONCLUSIONS

Thus, this study found marked evidence in support of the marriage market and social obligation theories' predictions about male BMI, and supports neither marriage protection theory nor marriage selection theory. Wives' pregnancies had no significant effect on BMI; instead, men tend to have higher BMI in the periods following childbirth. Finally, analyses showed marked contemporaneous correlations between husband and wife BMI over the course of marriage.

Genetic interaction of DGAT2 and FAAH in the development of human obesity

PURPOSE

DGAT2 is the critical catalyzing enzyme for triglyceride biosynthesis, and excess triglyceride accumulation in fat tissues is a fundamental process for obesity. Mutations in DGAT2 or other genes interacting with DGAT2 associated with adiposity have not been reported in human to date.

METHODS

DGAT2 mutation was identified based on our in-home database-exome sequencing 227 young obese subjects (body-mass index (BMI), 35.1-61.7 kg/m²) and 219 lean controls (BMI, 17.5-23.0 kg/m²), further validated in 1190 lean subjects and the pedigree of the proband. The trios of the proband were further subjected to whole-exome sequencing to explore the candidate genes for obesity. The mutations in DGAT2 and FAAH were functionally evaluated in vitro.

RESULTS

We detected two rare variants in DGAT2 with no significant difference between obese and lean individuals. One novel heterozygous nonsense variant c.382C > T (p.R128*) was identified in one obese subject but not in 219 lean subjects and another 1190 lean subjects. Notably, in vitro study showed that R128* mutation severely damaged the TG-biosynthesis ability of DGAT2, and all other R128* carriers in the pedigree were lean. Thus, we further identified a loss-of-function variant c. 944G > T (p.R315I) in FAAH in the proband inheriting from his obese father. Importantly, FAAH overexpression inhibited DGAT2 expression and TG synthesis, while R315I mutant largely eliminated this inhibitory effect. We first report loss-of-function mutations in DGAT2 and FAAH in one obese subject, which may interact with each other to affect the adiposity penetrance, providing a model of genetic interaction associated with human obesity.

Estradiol effects on hypothalamic AMPK and BAT thermogenesis: A gateway for obesity treatment?

In addition to their prominent roles in the control of reproduction, estrogens are important modulators of energy balance, as evident in conditions of deficiency of estrogens, which are characterized by increased feeding and decreased energy expenditure, leading to obesity. AMP-activated protein kinase (AMPK) is a ubiquitous cellular energy gauge that is activated under conditions of low energy, increasing energy production and reducing energy wasting. Centrally, the AMPK pathway is a canonical route regulating energy homeostasis, by integrating peripheral signals, such as hormones and metabolites, with neuronal networks. As a result of those actions, hypothalamic AMPK modulates feeding, as well as brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT). Here, we will review the central actions of estrogens on energy balance, with particular focus on hypothalamic AMPK. The relevance of this interaction is noteworthy, because some agents with known actions on metabolic homeostasis, such as nicotine, metformin, liraglutide, olanzapine and also natural molecules, such as resveratrol and flavonoids, exert their actions by modulating AMPK. This evidence highlights the possibility that hypothalamic AMPK might be a potential target for the treatment of obesity.

A Comparison of Radiographic Outcomes After Total Hip Arthroplasty Between the Posterior Approach and Direct Anterior Approach With Intraoperative Fluoroscopy

BACKGROUND

Radiographic outcomes after total hip arthroplasty (THA) have been linked to clinical outcomes. The direct anterior approach (DAA) for THA has been criticized by some for providing limited exposure and compromised implant position but allows for routine use of intraoperative fluoroscopy. We sought to determine whether radiographic measurements differed by THA approach using prospective cohorts.

METHODS

Two reviewers blinded to surgical approach examined 194 radiographs, obtained 4-6 weeks after primary THA, and obtained measurements for acetabular inclination angle, acetabular anteversion, radiographic limb length discrepancy (LLD), and femoral offset. All surgeries were performed at a tertiary academic medical center in rural New England by an experienced fellowship-trained arthroplasty surgeon. Measurements for inclination angle, anteversion, LLD, and offset were made into binary yes/no responses based on whether the mean measurement (between the 2 reviewers) was acceptable or not based on established criteria. Multivariate logistic regression analyses were performed using preoperative and intraoperative characteristics to identify predictors of acceptability for each measurement.

RESULTS

The DAA group had higher rates of acceptable acetabular angle (96 vs 85%, P = .005) and was protective against an unacceptable angle in an adjusted predictive model (odds ratios 0.16, P = .005). There were no significant differences between approaches for acceptable anteversion, LLD, or offset. Body mass index of 30-34 was associated with higher odds of unacceptable inclination angle compared to the nonobese group (adjusted odds ratio, 6.82, P = .013).

CONCLUSION

DAA for THA was associated with lower odds of unacceptable inclination angle compared to the posterior approach, with no differences in anteversion, LLD, or offset.

Integrative genomic analysis implicates limited peripheral adipose storage capacity in the pathogenesis of human insulin resistance

Insulin resistance is a key mediator of obesity-related cardiometabolic disease, yet the mechanisms underlying this link remain obscure. Using an integrative genomic approach, we identify 53 genomic regions associated with insulin resistance phenotypes (higher fasting insulin levels adjusted for BMI, lower HDL cholesterol levels and higher triglyceride levels) and provide evidence that their link with higher cardiometabolic risk is underpinned by an association with lower adipose mass in peripheral compartments. Using these 53 loci, we show a polygenic contribution to familial partial lipodystrophy type 1, a severe form of insulin resistance, and highlight shared molecular mechanisms in common/mild and rare/severe insulin resistance. Population-level genetic analyses combined with experiments in cellular models implicate CCDC92, DNAH10 and L3MBTL3 as previously unrecognized molecules influencing adipocyte differentiation. Our findings support the notion that limited storage capacity of peripheral adipose tissue is an important etiological component in insulin-resistant cardiometabolic disease and highlight genes and mechanisms underpinning this link.

Gene Expression Patterns Are Altered in Athymic Mice and Metabolic Syndrome Factors Are Reduced in C57BL/6J Mice Fed High-Fat Diets Supplemented with Soy Isoflavones

Soy isoflavones exert beneficial health effects; however, their potential to ameliorate conditions associated with the metabolic syndrome (MetS) has not been studied in detail. In vitro and in vivo models were used to determine the effect of isoflavones on lipid metabolism, inflammation, and oxidative stress. In nude mice, consumption of Novasoy (NS) increased cholesterol and lipid metabolism gene expression, including Scd-1 (27.7-fold), Cyp4a14 (35.2-fold), and Cyp4a10 (9.5-fold), and reduced anti-inflammatory genes, including Cebpd (16.4-fold). A high-fat (HF) diet containing 0.4% (w/w) NS for 10 weeks significantly reduced percent weight gain (74.6 ± 2.5 vs 68.6 ± 3.5%) and hepatic lipid accumulation (20 ± 1.2 vs 27 ± 1.5%), compared to HF alone (p < 0.05) in C57BL/6J mice. NS also increased lipid oxidation and antioxidant gene expression while decreasing inflammatory cytokines. In vitro analysis in HepG2 cells revealed that genistein dose-dependently decreases oleic acid-induced lipid accumulation. Soy isoflavones may ameliorate symptoms associated with MetS via anti-inflammatory, antioxidant, and hypolipidemic modulation.

Flurbiprofen Ameliorates Glucose Deprivation-Induced Leptin Resistance

Leptin resistance is one of the mechanisms involved in the pathophysiology of obesity. The present study showed that glucose deprivation inhibited leptin-induced phosphorylation of signal transducer and activator of transcription 3 (STAT3) and signal transducer and activator of transcription 5 (STAT5) in neuronal cells. Flurbiprofen reversed glucose deprivation-mediated attenuation of STAT3, but not STAT5 activation, in leptin-treated cells. Glucose deprivation increased C/EBP-homologous protein and glucose regulated protein 78 induction, indicating the activation of unfolded protein responses (UPR). Flurbiprofen did not affect the glucose deprivation-induced activation of UPR, but did attenuate the glucose deprivation-mediated induction of AMP-activated protein kinase phosphorylation. Flurbiprofen may ameliorate glucose deprivation-induced leptin resistance in neuronal cells.

Dose-related antihyperglycemic and hypolipidemic effects of two novel thiazolidin-4-ones in a rodent model of metabolic syndrome

BACKGROUND

The replacement of the thiazolidinedione moiety with a thiazolidinone may yield antidiabetic compounds with similar pleiotropic effects. Hence, the aim of the present study was to explore the dose-related antihyperglycemic and hypolipidemic effects of two synthesized novel thiazolidin-4-one derivatives, one with a nicotinamide and the other with a p-chlorophenoxyacetamide substitution at the N3 position of the thiazolidinone ring (NAT1 and PAT1, respectively), in a rodent model of metabolic syndrome (MetS).

METHODS

Metabolic syndrome was induced in Wistar rats by neonatal administration of monosodium glutamate (i.p.) on 4 consecutive days followed by high-sucrose diet feeding for 6 months. The effects of NAT1 (33 and 66 mg/kg) and molar equivalent doses of PAT1 (40 and 80 mg/kg) on relevant biochemical parameters were evaluated. Because MetS is a state of chronic low-grade inflammation, we also evaluated the effects of these compounds on proinflammatory markers, namely interleukin (IL)-6, tumor necrosis factor (TNF)-α, reactive oxygen species (ROS), and nitric oxide (NO).

RESULTS

Both NAT1 and PAT1 attenuated hyperglycemia, hypertriglyceridemia, hypoalphalipoproteinemia, and glucose intolerance. PAT1 exhibited superior antihyperglycemic and antihypoalphalipoproteinemic effects than NAT1. However, NAT1 had a better triglyceride-lowering effect. At the lower dose tested, both compounds significantly reduced elevated malondialdehyde levels. In addition, PAT1 (80 mg/kg) restored hepatic superoxide dismutase enzyme levels. There was a tendency for NAT1 and PAT1 to inhibit elevated hepatic IL-6 and TNF-α levels, but the differences did not reach statistical significance. In addition, PAT1 exhibited in vitro anti-inflammatory activity by reducing proinflammatory ROS and NO levels in RAW264.7 macrophages.

CONCLUSIONS

The novel thiazolidin-4-ones NAT1 and PAT1 could be potential pleiotropic drug candidates targeting MetS.

FTO Obesity Risk Variants Are Linked to Adipocyte IRX3 Expression and BMI of Children - Relevance of FTO Variants to Defend Body Weight in Lean Children?

BACKGROUND

Genome-wide association studies have identified variants within the FTO (fat mass and obesity associated) locus as the strongest predictors of obesity amongst all obesity-associated gene loci. Recent evidence suggests that variants in FTO directly affect human adipocyte function through targeting IRX3 and IRX5 and thermogenesis regulation.

AIM

We addressed the relevance of this proposed FTO-IRX pathway in adipose tissue (AT) of children.

RESULTS

Expression of IRX3 was higher in adipocytes compared to SVF. We found increased adipocyte-specific expression of IRX3 and IRX5 with the presence of the FTO risk haplotype in lean children, whereas it was unaffected by risk variants in obese peers. We further show that IRX3 expression was elevated in isolated adipocytes and AT of lean compared to obese children, particularly in UCP1-negative adipocytes, and inversely correlated with BMI SDS. Independent of BMI, IRX3 expression in adipocytes was significantly related to adipocyte hypertrophy, and subsequent associations with AT inflammation and HOMA-IR in the children.

CONCLUSION

One interpretation of our observation of FTO risk variants linked to IRX3 expression and adipocyte size restricted to lean children, along with the decreased IRX3 expression in obese compared to lean peers, may reflect a defense mechanism for protecting body-weight, which is pertinent for lean children.

Estradiol and brown fat

Ovarian steroids, such as estradiol (E2), control a vastness of physiological processes, such as puberty, reproduction, growth, development and metabolic rate. In fact, physiological, pathological, pharmacological or genetically-induced estrogen deficiency causes increased appetite and reduced energy expenditure, promoting weight gain and ultimately leading to obesity. Remarkably, estrogen replacement reverts those effects. Interestingly, although a wealth of evidence has shown that E2 can directly modulate peripheral tissues to exert their metabolic actions, novel data gathered in recent years have shown that those effects are mainly central and occur in the hypothalamus. Here, we will review what is known about the actions of E2 on energy homeostasis, with particular focus on brown adipose tissue (BAT) thermogenesis.

The Role of Circulating Amino Acids in the Hypothalamic Regulation of Liver Glucose Metabolism

A pandemic of diabetes and obesity has been developing worldwide in close association with excessive nutrient intake and a sedentary lifestyle. Variations in the protein content of the diet have a direct impact on glucose homeostasis because amino acids (AAs) are powerful modulators of insulin action. In this work we review our recent findings on how elevations in the concentration of the circulating AAs leucine and proline activate a metabolic mechanism located in the mediobasal hypothalamus of the brain that sends a signal to the liver via the vagus nerve, which curtails glucose output. This neurogenic signal is strictly dependent on the metabolism of leucine and proline to acetyl-coenzyme A (CoA) and the subsequent production of malonyl-CoA; the signal also requires functional neuronal ATP-sensitive potassium channels. The liver then responds by lowering the rate of gluconeogenesis and glycogenolysis, ultimately leading to a net decrease in glucose production and in concentrations of circulating glucose. Furthermore, we review here how our work with proline suggests a new role of astrocytes in the central regulation of glycemia. Last, we outline how factors such as the consumption of fat-rich diets can interfere with glucoregulatory mechanisms and, in the long term, may contribute to the development of hyperglycemia, a hallmark of type 2 diabetes.

Key role of heat shock protein 90 in leptin-induced STAT3 activation and feeding regulation

BACKGROUND AND PURPOSE

Leptin, an important regulator of the energy balance, acts on the brain to inhibit feeding. However, the mechanisms involved in leptin signalling have not yet been fully elucidated. Heat shock protein 90 (HSP90) is a molecular chaperone that is involved in regulating cellular homeostasis. In the present study, we investigated the possible involvement of HSP90 in leptin signal transduction.

EXPERIMENTAL APPROACH

HEK293 and SH-SY5Y cell lines stably transfected with the Ob-Rb leptin receptor (HEK293 Ob-Rb, SH-SY5Y Ob-Rb) were used in the present study. Phosphorylation of JAK2 and STAT3 was analysed by western blotting. An HSP90 inhibitor was administered i.c.v. into rats and their food intake was analysed.

KEY RESULTS

The knock-down of HSP90 in the HEK293 Ob-Rb cell line attenuated leptin-induced JAK2 and STAT3 signalling. Moreover, leptin-induced JAK2/STAT3 phosphorylation was markedly attenuated by the HSP90 inhibitors geldanamycin, radicicol and novobiocin. However, these effects were not mediated through previously known factors, which are known to be involved in the development of leptin resistance, such as suppressor of cytokine signalling 3 or endoplasmic reticulum stress. The infusion of an HSP90 inhibitor into the CNS blunted the anorexigenic actions of leptin in rats (male Wister rat).

CONCLUSIONS AND IMPLICATIONS

HSP90 may be a novel factor involved in leptin-mediated signalling that is linked to anorexia.

Role of adiponectin gene variants, adipokines and hydrometry-based percent body fat in metabolically healthy and abnormal obesity

OBJECTIVE

Metabolically healthy obesity (MHO) subjects have better metabolic parameters than metabolically abnormal obesity (MAO) subjects, but the possible mechanisms underlying this remain unknown. Our study was designed to investigate the interrelationships among genes, adipokines, body fat and its distribution in MHO and MAO.

METHODS

From 2007 to 2009, 103 males and 131 females aged 18-50 years were enrolled by an intention-to-treat design in a weight management clinic. Participants were divided into MHO and MAO groups. Percent body fat (PBF) was measured by a deuterium oxide dilution method. Four polymorphic variants, including PPARγ2 (Pro12Ala and C1431T) and adiponectin (T45G and G276T) genes, and three adipokines (adiponectin, leptin and resistin) were obtained.

RESULTS

Of the 234 obese subjects, 130 (55.6%) were MHO. In the univariate analysis, the MAO group has significantly higher anthropometric, metabolic indices and leptin levels than the MHO group. Logistic regression analysis revealed that age, male gender, the T allele of adiponectin T45G polymorphism, leptin and PBF were positively associated with MAO. ANCOVA analysis revealed that the T allele of adiponectin T45G polymorphism was associated with higher fasting and postprandial glucose levels. We further found that TT genotype has a lower high molecular weight (HMW)/low molecular weight (LMW) adiponectin ratio than GG genotype.

CONCLUSIONS

The factors associated with MAO are age, male gender, the T allele of adiponectin T45G polymorphism, leptin, and PBF. The net effects of T45G polymorphism on the MAO phenotype may be achieved by changes in the adiponectin oligomer ratio and glucose levels.

Association of Circulating Follistatin-Like 1 Levels with Inflammatory and Oxidative Stress Markers in Healthy Men

Objectives

Follistatin-like 1 (Fstl1) is a circulating glycoprotein that plays a crucial role in cardiovascular diseases and inflammation-related disorders. We have shown that Fstl1 acts as an anti-inflammatory factor that protects against ischemic heart disease and chronic kidney disease. Here we examined whether plasma level of Fstl1 associates with markers of inflammation and oxidative stress in apparently healthy Japanese men.

Methods and Results

Plasma Fstl1 levels were measured by enzyme-linked immunosorbent assay. Circulating Fstl1 concentrations positively correlated with levels of fasting immune-reactive insulin (FIRI), high-sensitive CRP (hsCRP) and derivatives of reactive oxidative metabolites (dROMs), an indicator of oxidative stress. The levels of hsCRP positively associated with Fstl1, body mass index (BMI), triglyceride, FIRI and dROMs levels. dROMs levels positively associated with Fstl1, Hemoglobin A1c and hsCRP levels. Multiple regression analysis with confounding factors revealed that Fstl1 levels, together with BMI and FIRI, correlated with hsCRP and that Fstl1 levels correlated with dROMs.

Conclusion

Our observations indicate that measurement of plasma Fstl1 levels can be valuable for assessment of pro-inflammatory and oxidative stress conditions.

Disruption of the sugar-sensing receptor T1R2 attenuates metabolic derangements associated with diet-induced obesity

Sweet taste receptors (STRs) on the tongue mediate gustatory sweet sensing, but their expression in the gut, pancreas, and adipose tissue suggests a physiological contribution to whole body nutrient sensing and metabolism. However, little is known about the function and contribution of these sugar sensors during metabolic stress induced by overnutrition and subsequent obesity. Here, we investigated the effects of high-fat/low-carbohydrate (HF/LC) diet on glucose homeostasis and energy balance in mice with global disruption of the sweet taste receptor protein T1R2. We assessed body composition, energy balance, glucose homeostasis, and tissue-specific nutrient metabolism in T1R2 knockout (T1R2-KO) mice fed a HF/LC diet for 12 wk. HF/LC diet-fed T1R2-KO mice gained a similar amount of body mass as did WT mice, but had reduced fat mass and increased lean mass relative to WT mice. T1R2-KO mice were also hyperphagic and hyperactive. Ablation of the T1R2 sugar sensor protected mice from HF/LC diet-induced hyperinsulinemia and altered substrate utilization, including increased rates of glucose oxidation and decreased liver triglyceride (TG) accumulation, despite normal intestinal fat absorption. Finally, STRs (T1r2/T1r3) were upregulated in the adipose tissue of WT mice in response to HF/LC diet, and their expression positively correlated with fat mass and glucose intolerance. The chemosensory receptor T1R2, plays an important role in glucose homeostasis during diet-induced obesity through the regulation of yet to be identified molecular mechanisms that alter energy disposal and utilization in peripheral tissues.

The Obesities: An Overview of Convergent and Divergent Paradigms

The study of obesity lends itself to difficulties not only due to our imprecise ability to measure body composition, food consumption, and physical activity but also, even more important, due to complexities involved in defining and conceptualizing obesity. For centuries, obesity has been considered a disease, although researchers and clinicians cannot agree on definitions of "disease" or, if it is one, whether obesity is a disease of metabolism, inflammation, brown fat, chronobiology, the blood-brain barrier, the right brain, or even of infectious origin. The concept of "obesity" as a disease remains controversial to some because not everyone who has excess adipose tissue has any evidence of disease. Obesity, though, has also been considered a sin, a crime against society, an aesthetic crime, a self-inflicted disability, an example of body diversity, a failure in the regulation of energy balance, an appropriate or even inappropriate adaptation to our increasingly obesogenic environment, a genetic disorder, and a psychological/behavioral disorder of overeating involving self-regulation or even addiction. Five major paradigms-medical, sociocultural, evolutionary, environmental, and psychological/behavioral, all with their own subcategorical models-have been identified. All 5 paradigms are required because we are dealing not with "obesity" but with a plurality, the "obesities."

Possible Pharmacological Approach Targeting Endoplasmic Reticulum Stress to Ameliorate Leptin Resistance in Obesity

Obesity is associated with metabolic syndrome, such as diabetes, hypertension, and hyperlipidemia. Therefore, drug development for the treatment of obesity is needed. Leptin is an anti-obesity hormone that inhibits food intake and increases energy metabolism, and, as such, treatments involving leptin were expected to be beneficial for obesity; however, since most obese patients are in a state of leptin resistance, these treatments may not be useful. Therefore, the amelioration of leptin resistance has recently been attracting interest as a treatment for obesity. The mechanisms underlying the development of leptin resistance need to be elucidated in more detail. Endoplasmic reticulum (ER) stress was recently suggested to be involved in the pathogenesis of leptin resistance. The molecular mechanisms responsible for leptin resistance and possible pharmacological treatments for obesity have been discussed herein, with a focus on ER stress.

Determination of UCP1 expression in subcutaneous and perirenal adipose tissues of patients with hypertension

The objective of this study is to determine the property of human perirenal adipose tissue (PAT) and assess the adipose property of PAT in hypertension. Ninety-four patients, including 64 normotensive patients (T-NP) and 30 hypertensive patients (HP), who underwent renal surgery were included. Expression analysis was performed using quantitative real-time polymerase chain reaction, Western blot, and immunohistochemistry in PAT and back subcutaneous adipose tissue (bSAT) depots. Compared with bSAT, PAT adipocytes were smaller, and the expressions of uncoupling protein-1 (UCP1) mRNA and protein were markedly higher, while the mRNA expressions of markers for classic beige and white adipocytes were lower in PAT. Immunohistochemistry analysis showed more multilocular UCP1-positive adipocytes in PAT than in bSAT. UCP1 expressions were lower in PAT in HP than in the T-NP or age- and body mass index-matched NP groups. Bigger unilocular adipocytes with less UCP1 staining in PAT were detected in HP than in NP group, although no such difference was observed in bSAT. PAT acts as a brown-like fat. UCP1 expression of PAT was lower in HP than in normotensive patients. UCP1 expression of PAT may serve as a protective indicator for hypertension.