Current pharmacotherapy for obesity

Structure based exploration of mitochondrial alpha carbonic anhydrase inhibitors as potential leads for anti-obesity drug development

BACKGROUND

Obesity has emerged as a major health challenge globally in the last two decades. Dysregulated fatty acid metabolism and de novo lipogenesis are prime causes for obesity development which ultimately trigger other co-morbid pathological conditions thereby risking life longevity. Fatty acid metabolism and de novo lipogenesis involve several biochemical steps both in cytosol and mitochondria. Reportedly, the high catalytically active mitochondrial carbonic anhydrases (CAVA/CAVB) regulate the intercellular depot of bicarbonate ions and catalyze the rapid carboxylation of pyruvate and acetyl-co-A to acetyl-co-A and malonate respectively, which are the precursors of fatty acid synthesis and lipogenesis. Several in vitro and in vivo investigations indicate inhibition of mitochondrial carbonic anhydrase isoforms interfere in the functioning of pyruvate, fatty acid and succinate pathways. Targeting of mitochondrial carbonic anhydrase isoforms (CAVA/CAVB) could thereby modulate gluconeogenetic as well as lipogenetic pathways and pave way for designing of novel leads in the development pipeline of anti-obesity medications.

METHODS

The present review unveils a diverse chemical space including synthetic sulphonamides, sulphamates, sulfamides and many natural bioactive molecules which selectively inhibit the mitochondrial isoform CAVA/CAVB with an emphasis on major state-of-art drug design strategies.

RESULTS

More than 60% similarity in the structural framework of the carbonic anhydrase isoforms has converged the drug design methods towards the development of isoform selective chemotypes. While the benzene sulphonamide derivatives selectively inhibit CAVA/CAVB in low nanomolar ranges depending on the substitutions on the phenyl ring, the sulpamates and sulpamides potently inhibit CAVB. The virtual screening and drug repurposing methods have also explored many non-sulphonamide chemical scaffolds which can potently inhibit CAVA.

CONCLUSION

The review could pave way for the development of novel and effective anti-obesity drugs which can modulate the energy metabolism.

Metabolomics and molecular docking-directed anti-obesity study of the ethanol extract from Gynostemma pentaphyllum (Thunb.) Makino

ETHNOPHARMACOLOGICAL RELEVANCE

Gynostemma pentaphyllum (Thunb.) Makino (G. pentaphyllum) is an oriental herb documented to treat many diseases, including obesity, hyperlipidemia, metabolic syndromes and aging. However, the anti-obesity mechanism of G. pentaphyllum remains poorly understood.

AIM OF THE STUDY

To reveal the anti-obesity mechanism of G. pentaphyllum Extract (GPE) in High-Fat Diet (HFD)-induced obese mice through untargeted metabolomics, Real-Time Quantitative PCR (RT-qPCR), and immunohistochemical experiments. Additionally, to tentatively identify the active constituents through LC-MS/MS and molecular docking approaches.

MATERIALS AND METHODS

GPE was prepared using ethanol reflux and purified by HP-20 macroporous resins. The components of GPE were identified by Liquid Chromatography- Mass Spectrometry (LC-MS) system. Forty-two C57BL/6 J mice were randomly and evenly divided into six groups, with seven mice in each group: the control group, obese model group, Beinaglutide group (positive control), and GPE low, medium, and high-dose groups (50 mg/kg, 100 mg/kg, and 200 mg/kg of 80% ethanol extract). Body weight, liver weight, blood glucose, blood lipids, and liver histopathological changes were assessed. Untargeted metabolomics was employed to characterize metabolic changes in obese mice after GPE treatment. The expression of genes related to differential metabolites was verified using Real-Time Quantitative PCR (RT-qPCR) and immunohistochemical experiments. The constituents with anti-obesity effects from GPE were tentatively identified through molecular docking approaches.

RESULTS

A total of 17 compounds were identified in GPE. GPE significantly lowered body weight, total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in obese mice and reduced liver weight and hepatic steatosis. Serum metabolomics identified 20 potential biomarkers associated with GPE treatment in obese mice, primarily related to tryptophan metabolism. GPE treatment downregulated the expression of Slc6a19 and Tph1 and upregulated Ucp1 expression. Molecular docking illustrated that compounds such as 20(R)-ginsenoside Rg3, Araliasaponin I, Damulin B, Gypenoside L, Oleifolioside B, and Tricin7-neohesperidoside identified in GPE exhibited favorable interaction with Tph1.

CONCLUSION

The extract of G. pentaphyllum can inhibit the absorption of tryptophan and its conversion to 5-HT through the Slc6a19/Tph1 pathway, upregulating the expression of Ucp1, thereby promoting thermogenesis in brown adipose tissue, facilitating weight loss, and mitigating symptoms of fatty liver. Triterpenoids such as Araliasaponin I, identified in GPE, could be the potential inhibitor of Tph1 and responsible for the anti-obesity activities.

Differential Efficacy of Weight Loss Interventions in Patients with Versus Without Diabetes

Obesity is both a major risk factor for diabetes and a serious comorbidity of the condition. The twin epidemics of obesity and diabetes have spread globally over the past few decades. Treatment of obesity in patients with diabetes provides a host of clinical benefits that encompass virtually all body systems. Despite this, multiple lines of evidence suggest that the efficacy of most therapies for weight loss is significantly reduced among patients with diabetes. With this background, we summarize the evidence of a differential effect of lifestyle, pharmacological, and surgical treatments for obesity in patients with existing diabetes, and explore the potential mechanisms involved in this phenomenon. This information is then used to formulate strategies to improve weight loss outcomes for patients with diabetes.

Estimating the lives that could be saved by expanded access to weight-loss drugs

Obesity is a major public health crisis in the United States (US) affecting 42% of the population, exacerbating a spectrum of other diseases and contributing significantly to morbidity and mortality overall. Recent advances in pharmaceutical interventions, particularly glucagon-like peptide-1 (GLP-1) receptor agonists (e.g., semaglutide, liraglutide) and dual gastric inhibitory polypeptide and GLP-1 receptor agonists (e.g., tirzepatide), have shown remarkable efficacy in weight-loss. However, limited access to these medications due to high costs and insurance coverage issues restricts their utility in mitigating the obesity epidemic. We quantify the annual mortality burden directly attributable to limited access to these medications in the US. By integrating hazard ratios of mortality across body mass index categories with current obesity prevalence data, combined with healthcare access, willingness to take the medication, and observed adherence to and efficacy of the medications, we estimate the impact of making these medications accessible to all those eligible. Specifically, we project that with expanded access, over 42,000 deaths could be averted annually, including more than 11,000 deaths among people with type 2 diabetes. These findings underscore the urgent need to address barriers to access and highlight the transformative public health impact that could be achieved by expanding access to these novel treatments.

Phytoactives for Obesity Management: Integrating Nanomedicine for Its Effective Delivery

Obesity is a global health concern that requires urgent investigation and management. While synthetic anti-obesity medications are available, they come with a high risk of side-effects and variability in their efficacy. Therefore, natural compounds are increasingly being used to treat obesity worldwide. The proposition that naturally occurring compounds, mainly polyphenols, can be effective and safer for obesity management through food and nutrient fortification is strongly supported by extensive experimental research. This review focuses on the pathogenesis of obesity while reviewing the efficacy of an array of phytoactives used for obesity treatment. It details mechanisms such as enzyme inhibition, energy expenditure, appetite suppression, adipocyte differentiation, lipid metabolism, and modulation of gut microbiota. Comprehensive in vitro, in vivo, and preclinical studies underscore the promise of phytoactives in combating obesity, which have been thoroughly reviewed. However, challenges, such as poor bioavailability and metabolism, limit their potential. Advances in nanomedicines may overcome these constraints, offering a new avenue for enhancing the efficacy of phytoactives. Nonetheless, rigorous and targeted clinical trials are essential before applying phytoactives as a primary treatment for obesity.

Sortilin-mediated translocation of mitochondrial ACSL1 impairs adipocyte thermogenesis and energy expenditure in male mice

Beige fat activation involves a fuel switch to fatty acid oxidation following chronic cold adaptation. Mitochondrial acyl-CoA synthetase long-chain family member 1 (ACSL1) localizes in the mitochondria and plays a key role in fatty acid oxidation; however, the regulatory mechanism of the subcellular localization remains poorly understood. Here, we identify an endosomal trafficking component sortilin (encoded by Sort1) in adipose tissues that shows dynamic expression during beige fat activation and facilitates the translocation of ACSL1 from the mitochondria to the endolysosomal pathway for degradation. Depletion of sortilin in adipocytes results in an increase of mitochondrial ACSL1 and the activation of AMPK/PGC1α signaling, thereby activating beige fat and preventing high-fat diet (HFD)-induced obesity and insulin resistance. Collectively, our findings indicate that sortilin controls adipose tissue fatty acid oxidation by substrate fuel selection during beige fat activation and provides a potential targeted approach for the treatment of metabolic diseases.

Metagenomic and metabolomic analysis showing the adverse risk-benefit trade-off of the ketogenic diet

BACKGROUND

Ketogenic diets are increasingly popular for addressing obesity, but their impacts on the gut microbiota and metabolome remain unclear. This paper aimed to investigate how a ketogenic diet affects intestinal microorganisms and metabolites in obesity.

METHODS

Male mice were provided with one of the following dietary regimens: normal chow, high-fat diet, ketogenic diet, or high-fat diet converted to ketogenic diet. Body weight and fat mass were measured weekly using high-precision electronic balances and minispec body composition analyzers. Metagenomics and non-targeted metabolomics data were used to analyze differences in intestinal contents.

RESULTS

Obese mice on the ketogenic diet exhibited notable improvements in weight and body fat. However, these were accompanied by a significant decrease in intestinal microbial diversity, as well as an increase in Firmicutes abundance and a 247% increase in the Firmicutes/Bacteroidetes ratio. The ketogenic diet also altered multiple metabolic pathways in the gut, including glucose, lipid, energy, carbohydrate, amino acid, ketone body, butanoate, and methane pathways, as well as bacterial secretion and colonization pathways. These changes were associated with increased intestinal inflammation and dysbiosis in obese mice. Furthermore, the ketogenic diet enhanced the secretion of bile and the synthesis of aminoglycoside antibiotics in obese mice, which may impair the gut microbiota and be associated with intestinal inflammation and immunity.

CONCLUSIONS

The study suggest that the ketogenic diet had an unfavorable risk-benefit trade-off and may compromise metabolic homeostasis in obese mice.

ACTION APAC: Understanding perceptions, attitudes and behaviours in obesity and its management across south and Southeast Asia

To identify perceptions and attitudes among people with obesity (PwO) and healthcare professionals (HCPs) toward obesity and its management in nine Asia-Pacific (APAC) countries, a cross-sectional online survey was conducted among adult PwO with self-reported body mass index of ≥25 kg/m2 (≥27 kg/m2, Singapore), and HCPs involved in direct patient care. In total, 10 429 PwO and 1901 HCPs completed the survey. Most PwO (68%) and HCPs (84%) agreed that obesity is a disease; however, a significant proportion of PwO (63%) and HCPs (41%) believed weight loss was the complete responsibility of PwO and only 43% of PwO discussed weight with an HCP in the prior 5 years. Most respondents acknowledged that weight loss would be extremely beneficial to PwO's overall health (PwO 76%, HCPs 85%), although nearly half (45%) of PwO misperceived themselves as overweight or of normal weight. Obesity was perceived by PwO (58%) and HCPs (53%) to negatively impact PwO forming romantic relationships. HCPs cited PwOs' lack of interest (41%) and poor motivation (37%) to lose weight as top reasons for not discussing weight. Most PwO (65%) preferred lifestyle changes over medications to lose weight. PwO and HCPs agreed that lack of exercise and unhealthy eating habits were the major barriers to weight loss. Our data highlights a discordance between the understanding of obesity as a disease and the actual behaviour and preferred approaches to manage it among PwO and HCPs. The study addresses a need to align these gaps to deliver optimal care for PwO.

Comprehensive transition of care for polycystic ovary syndrome from adolescence to adulthood

Polycystic ovary syndrome (PCOS) is a lifelong chronic condition that affects one in ten females and can be diagnosed in adolescence. As adolescents with PCOS transition to adulthood, counselling for lifestyle management and mental health concerns often transition from involving the family unit to increasingly individual-focused approaches. PCOS is associated with a large range of comorbidities affecting reproductive, metabolic, dermatological, and psychological health. The diagnosis and comorbidities of PCOS are influenced by pubertal hormones and need to be reassessed continuously to ensure that treatment remains appropriate for age and development. As young patients grow up, personal concerns often change, especially in relation to reproductive management. In this Review, we present prevalence rates, screening tools, and treatment recommendations for PCOS-related conditions, and we consider the diagnostic and clinical elements of optimal transition of care models that ensure continuity of comprehensive care for adolescents moving from the paediatric health-care system to the adult health-care system.

The effect of obesity pharmacotherapy on body composition, including muscle mass

Obesity pharmacotherapy represents a promising approach to treating obesity and may provide benefits beyond weight loss alone. Maintaining or even increasing muscle mass during weight loss is important to overall health, metabolic function and weight loss maintenance. Drugs such as liraglutide, semaglutide, tirzepatide, and naltrexone/bupropion have shown significant weight loss effects, and emerging evidence suggests they may also have effects on body composition, particularly a positive influence on muscle mass. However, further research is needed to fully understand the mechanism of action of these drugs and their effects on muscle mass. Clinicians should consider these factors when developing an obesity treatment plan for an individual patient.

A computational study to probe the binding aspects of potent polyphenolic inhibitors of pancreatic lipase

Pancreatic lipase (PL) is a keen target for anti-obesity therapy that reduces dietary fat absorption. Here, we investigated the binding patterns of 220 PL inhibitors having experimental IC50 values, using molecular docking and binding energy calculations. Screening of these compounds illustrated most of them bound at the catalytic site (S1-S2 channel) and a few compounds are at the non-catalytic site (S2-S3 channel/S1-S3 channel) of PL. This binding pattern could be due to structural uniqueness or bias in conformational search. A strong correlation of pIC50 values with SP/XP docking scores, binding energies (ΔGMMGBSA) assured the binding poses are more true positives. Further, understanding of each class and subclasses of polyphenols indicated tannins preferred non-catalytic site wherein binding energies are underestimated due to huge desolvation energy. In contrast, most of the flavonoids and furan-flavonoids have good binding energies due to strong interactions with catalytic residues. While scoring functions limited the understanding of sub-classes of flavonoids. Hence, focused on 55 potent PL inhibitors of IC50 < 5 µM for better in vivo efficacy. The prediction of bioactivity, drug-likeness properties, led to 14 bioactive compounds. The low root mean square deviation (0.1-0.2 nm) of these potent flavonoids and non-flavonoid/non-polyphenols PL-inhibitor complexes during 100 ns molecular dynamics runs (MD) as well as binding energies obtained from both MD and well-tempered metadynamics, support strong binding to catalytic site. Based on the bioactivity, ADMET properties, and binding affinity data of MD and wt-metaD of potent PL-inhibitors suggests Epiafzelechin 3-O-gallate, Sanggenon C, and Sanggenofuran A shall be promising inhibitors at in vivo conditions.Communicated by Ramaswamy H. Sarma.

Attitudes and knowledge about weight management among primary care physicians in Israel: a cross-sectional study

BACKGROUND

The prevalence of obesity has been increasing worldwide and is associated with increased risk of morbidity and mortality. Weight management can reduce the risk of complications and improve the quality of life of patients with obesity. This study explored primary care physicians' (PCPs') attitudes and knowledge about weight management.

METHODS

An anonymous questionnaire was distributed to 400 PCPs between 2020 and 2021. The survey included questions on treatment approaches (pharmaceutical and surgical) and items regarding the respondents' demographic characteristics. We compared PCPs with low or high proactivity toward weight management. We explored attitudes and knowledge with the chi-square test for categorical variables or the Mann-Whitney test for continuous variables.

RESULTS

A total of 145 PCPs answered our survey (a response rate of 36.25%). More than half (53.8%) of the respondents showed low proactivity toward weight management in their practice. Proactive respondents were more likely to believe that pharmaceutical treatment effectively reduces weight and offered medical and surgical treatment options more frequently to their patients. Lack of knowledge was the most predominant reason for PCPs avoiding offering treatment to their patients, especially in less proactive PCPs (33.3% vs. 5.3%, p-value < 0.001). When comparing different pharmaceutical options, 46.6% of PCPs report they tend to prescribe liraglutide to their patients compared with only 11% who prescribe orlistat and 10.3% who prescribe phentermine (p-value < 0.001).

CONCLUSIONS

Many PCPs still do not actively provide obesity treatment despite improved awareness and therapeutic options. PCPs' proactivity and attitudes are vital to this effort.

Mulberry and Hippophae-based solid beverage promotes weight loss in rats by antagonizing white adipose tissue PPARγ and FGFR1 signaling

Obesity, a multifactorial disease with many complications, has become a global epidemic. Weight management, including dietary supplementation, has been confirmed to provide relevant health benefits. However, experimental evidence and mechanistic elucidation of dietary supplements in this regard are limited. Here, the weight loss efficacy of MHP, a commercial solid beverage consisting of mulberry leaf aqueous extract and Hippophae protein peptides, was evaluated in a high-fat high-fructose (HFF) diet-induced rat model of obesity. Body component analysis and histopathologic examination confirmed that MHP was effective to facilitate weight loss and adiposity decrease. Pathway enrichment analysis with differential metabolites generated by serum metabolomic profiling suggests that PPAR signal pathway was significantly altered when the rats were challenged by HFF diet but it was rectified after MHP intervention. RNA-Seq based transcriptome data also indicates that MHP intervention rectified the alterations of white adipose tissue mRNA expressions in HFF-induced obese rats. Integrated omics reveals that the efficacy of MHP against obesogenic adipogenesis was potentially associated with its regulation of PPARγ and FGFR1 signaling pathway. Collectively, our findings suggest that MHP could improve obesity, providing an insight into the use of MHP in body weight management.

Effect and safety of electroacupuncture on weight loss in obese patients with pre-diabetes: study protocol of a randomised controlled trial

INTRODUCTION

Obesity has been identified as a significant risk factor for several chronic conditions, including diabetes, tumours and cardiovascular disease, and has been associated with increased mortality rates. Despite the well-established clinical practice of electroacupuncture (EA) as a potential treatment option for obesity, its efficacy remains questionable, primarily due to the paucity of empirical evidence supporting its therapeutic benefits.

METHODS AND ANALYSIS

The present study aims to investigate the efficacy and safety of EA for weight loss in obese individuals with pre-diabetes, using a randomised, placebo-controlled clinical trial design. A total of 256 eligible patients will be randomly assigned to one of two groups: EA (comprising EA treatment with health education) or superficial acupuncture (SA) (comprising SA treatment with health education). The intervention will be administered three times per week for the initial 12 weeks, two times per week for the subsequent 8 weeks and one time per week for the final 4 weeks, with a 24-week follow-up period. The primary outcome measure will be the percentage of patients who achieve a reduction of 10% or more in their body weight at week 24. Secondary outcome measures will include changes in body weight and body mass index, blood test results, data collected by the body composition analyser, size of adipose tissue scanned by MRI of the abdomen and the Impact of Weight on Quality of Life, the 21-item Three-Factor Eating Questionnaire-Revised and the Food Craving Questionnaire-Trait. The Treatment Emergent Symptom Scale will be employed to monitor every adverse reaction from baseline to follow-up.

ETHICS AND DISSEMINATION

This trial has received ethical clearance from the Ethics Committee of Shanghai Municipal Hospital of Traditional Chinese Medicine under the registration number 2021SHL-KY-74. All participants will provide their written informed consent prior to their enrolment. The findings of this investigation will be disseminated through peer-reviewed publications and scholarly conferences.

TRIAL REGISTRATION NUMBER

NCT05237089.

Cyy-287, a novel pyrimidine-2,4-diamine derivative, efficiently mitigates inflammatory responses, fibrosis, and lipid synthesis in obesity-induced cardiac and hepatic dysfunction

Background

Inflammation and metabolic disorders are important factors in the occurrence and development of obesity complications. In this study, we investigated the protective effect and underlying mechanism of a novel pyrimidine-2,4-diamine derivative, Cyy-287, on mice fed a high-fat diet (HFD).

Methods

The mice were randomly separated into four groups (n ≥ 7): control (regular diet), HFD, HFD with Cyy-287 (5 mg/kg), and HFD with Cyy-287 (20 mg/kg) following HFD feeding for 10 weeks. After a 10-week administration, ALT and AST enzymes, echocardiography, immunohistochemical (IHC), Western blot (WB), Masson and Sirius Red staining were used to evaluate functional and morphological changes to the heart and liver. Microsomes from the mouse liver were extracted to quantify the total amount of CYP450 enzymes after drug treatment.

Results

Cyy-287 decreased the levels of serum glucose, LDL, TC, ALT, and AST activities in HFD-treated mice. However, Cyy-287 administration increased ejection fraction (EF) and fractional shortening (FS) index of the heart. Cyy-287 inhibited histopathological changes in the heart and liver; decreased inflammatory activity; significantly diminished p38 mitogen-activated protein kinase (MAPK), the nuclear factor-kappa B (NF-κB) axis, and sterol regulatory element-binding protein-1c (SREBP-1c); and upregulated the AMP-activated protein kinase (AMPK) pathway in HFD-treated mice. Cyy-287 restored the content of hepatic CYP450 enzymes.

Conclusion

These findings demonstrated that Cyy-287 protected heart and liver cells from obesity-induced damage by inhibiting inflammation, fibrosis, and lipid synthesis.

Natural compounds as obesity pharmacotherapies

Obesity has become a serious global public health problem, affecting over 988 million people worldwide. Nevertheless, current pharmacotherapies have proven inadequate. Natural compounds have garnered significant attention due to their potential antiobesity effects. Over the past three decades, ca. 50 natural compounds have been evaluated for the preventive and/or therapeutic effects on obesity in animals and humans. However, variations in the antiobesity efficacies among these natural compounds have been substantial, owing to differences in experimental designs, including variations in animal models, dosages, treatment durations, and administration methods. The feasibility of employing these natural compounds as pharmacotherapies for obesity remained uncertain. In this review, we systematically summarized the antiobesity efficacy and mechanisms of action of each natural compound in animal models. This comprehensive review furnishes valuable insights for the development of antiobesity medications based on natural compounds.

A nanoemulsion targeting adipose hypertrophy and hyperplasia shows anti-obesity efficiency in female mice

Obesity often leads to severe medical complications. However, existing FDA-approved medications to combat obesity have limited effectiveness in reducing adiposity and often cause side effects. These medications primarily act on the central nervous system or disrupt fat absorption through the gastrointestinal tract. Adipose tissue enlargement involves adipose hyperplasia and hypertrophy, both of which correlate with increased reactive oxygen species (ROS) and hyperactivated X-box binding protein 1 (XBP1) in (pre)adipocytes. In this study, we demonstrate that KT-NE, a nanoemulsion loaded with the XBP1 inhibitor KIRA6 and α-Tocopherol, simultaneously alleviates aberrant endoplasmic reticulum stress and oxidative stress in (pre)adipocytes. As a result, KT-NE significantly inhibits abnormal adipogenic differentiation, reduces lipid droplet accumulation, restricts lipid droplet transfer, impedes obesity progression, and lowers the risk of obesity-associated non-alcoholic fatty liver disease in female mice with obesity. Furthermore, diverse administration routes of KT-NE impact its in vivo biodistribution and contribute to localized and/or systemic anti-obesity effectiveness.

A Newly Synbiotic Combination Alleviates Obesity by Modulating the Gut Microbiota-Fat Axis and Inhibiting the Hepatic TLR4/NF-κB Signaling Pathway

SCOPE

Obesity has been recognized as a worldwide public health crisis, this is accompanied by dysregulation of the intestinal microbiota and upregulation of liver steatosis and adipose inflammation. Synbiotic as a novel alternative therapy for obesity have recently gained much attention.

METHODS

This study innovatively research the anti-obesity properties of a newly synbiotic composed of Lactobacillus acidophilus, Bifidobacterium infantis and konjac glucomannan oligosaccharides.

RESULTS

The synbiotic treatment can reduce body weight, fat mass, blood sugar, liver steatosis and adipose inflammation in obesity mice fed by high-fat diet (HFD). Meanwhile, synbiotic treatment activated brown adipose tissue and improve energy, glucose and lipid metabolism. In addition, synbiotic treatment not solely enhanced the protection of intestinal barrier, but also ameliorated gut microbiota dysbiosis directly by enhancing beneficial microbes and reducing potentially harmful bacteria. Furthermore, the microbiome phenotype and functional prediction showed that synbiotic treatment can improve the gut microbiota functions involving inflammatory state, immune response, metabolism and pathopoiesia.

CONCLUSION

The synbiotic may be an effective candidate treatment strategy for the clinical prevention and treatment of obesity and other associated metabolic diseases such as hyperlipidemia, nonalcoholic fatty liver diseases by alleviating inflammatory response, regulating energy metabolism and maintaining the balance of intestinal microecology.

Anti-Obesity Drug Delivery Systems: Recent Progress and Challenges

Obesity has reached an epidemic proportion in the last thirty years, and it is recognized as a major health issue in modern society now with the possibility of serious social and economic consequences. By the year 2030, nearly 60% of the global population may be obese or overweight, which emphasizes a need for novel obesity treatments. Various traditional approaches, such as pharmacotherapy and bariatric surgery, have been utilized in clinical settings to treat obesity. However, these methods frequently show the possibility of side effects while remaining ineffective. There is, therefore, an urgent need for alternative obesity treatments with improved efficacy and specificity. Polymeric materials and chemical strategies are employed in emerging drug delivery systems (DDSs) to enhance therapy effectiveness and specificity by stabilizing and controlling the release of active molecules such as natural ingredients. Designing DDSs is currently a top priority research objective with an eye towards creating obesity treatment approaches. In reality, the most recent trends in the literature demonstrate that there are not enough in-depth reviews that emphasize the current knowledge based on the creation and design of DDSs for obesity treatment. It is also observed in the existing literature that a complex interplay of different physical and chemical parameters must be considered carefully to determine the effectiveness of the DDSs, including microneedles, for obesity treatment. Additionally, it is observed that these properties depend on how the DDS is synthesized. Although many studies are at the animal-study stage, the use of more advanced DDS techniques would significantly enhance the development of safe and efficient treatment approaches for obese people in the future. Considering these, this review provides an overview of the current anti-obesity treatment approaches as well as the conventional anti-obesity therapeutics. The article aims to conduct an in-depth discussion on the current trends in obesity treatment approaches. Filling in this knowledge gap will lead to a greater understanding of the safest ways to manage obesity.

Clostridium butyricum Strain CCFM1299 Reduces Obesity via Increasing Energy Expenditure and Modulating Host Bile Acid Metabolism

Clostridium butyricum is a butyrate-producing microorganism which has beneficial effects on various diseases, including obesity. In our previous study, the anti-obesity Clostridium butyricum strain CCFM1299 (C20_1_1) was selected, but its anti-obesity mechanism was not clarified. Herein, CCFM1299 was orally administrated to high-fat-diet-treated C57BL/6J mice for 12 weeks to uncover the way the strain alleviates obesity. The results indicated that CCFM1299 alleviated obesity through increasing the energy expenditure and increasing the expression of genes related to thermogenesis in brown adipose tissue (BAT). Moreover, strain CCFM1299 could also affect the expression of immune-related genes in epididymal white adipose tissue (eWAT). This immunomodulatory effect might be achieved through its influence on the complement system, as the expression of the complement factor D (CFD) gene decreased significantly. From the view of metabolites, CCFM1299 administration increased the levels of ursodeoxycholic acid (UDCA) in feces and taurohyodeoxycholic acid (THDCA) in serum. Together, the anti-obesity potential of CCFM1299 might be attributed to the increase in energy consumption, the regulation of immune-related gene expression in eWAT, and the alteration of bile acid metabolism in the host. These provided new insights into the potential application of anti-obesity microbial preparations and postbiotics.

Targeting Clic1 for the treatment of obesity: A novel therapeutic strategy to reduce food intake and body weight

OBJECTIVE

Despite great advances in obesity therapeutics in recent years, there is still a need to identify additional therapeutic targets for the treatment of this disease. We previously discovered a signature of genes, including Chloride intracellular channel 1 (Clic1), whose expression was associated with drug-induced weight gain, and in these studies, we assess the effect of Clic1 inhibition on food intake and body weight in mice.

METHODS

We studied the impact of Clic1 inhibition in mouse models of binge-eating, diet-induced obese mice and genetic models of obesity (Magel2 KO mice).

RESULTS

Clic1 knockout (KO) mice ate significantly less and had a lower body weight than WT littermates when either fed chow or high fat diet. Furthermore, pharmacological inhibition of Clic1 in diet-induced obese mice resulted in suppression of food intake and promoted highly efficacious weight loss. Clic1 inhibition also reduced food intake in binge-eating models and hyperphagic Magel2 KO mice. We observed that chronic obesity resulted in a significant change in subcellular localization of Clic1 with an increased ratio of Clic1 in the membrane in the obese state. These observations provide a novel therapeutic strategy to block Clic1 translocation as a potential mechanism to reduce food intake and lower body weight.

CONCLUSIONS

These studies attribute a novel role of Clic1 as a driver of food intake and overconsumption. In summary, we have identified hypothalamic expression of Clic1 plays a key role in food intake, providing a novel therapeutic target to treat overconsumption that is the root cause of modern obesity.

Increased Glucagon Immunoreactivity in a Rat Model of Diet-induced Obesity following Sleeve Gastrectomy

OBJECTIVE

Bariatric surgery is currently the most effective treatment for obesity, and procedures such as Roux-en Y gastric bypass and sleeve gastrectomy (SG) also result in rapid improvements in insulin sensitivity and glucose tolerance. In addition, these procedures cause changes in the secretion of various gut-derived hormones. The role these hormones play in the mechanism of the beneficial effects of bariatric surgery is still debated, but nonetheless, their importance provides inspiration for novel obesity-targeted pharmacotherapies.

METHODS

Male Sprague Dawley rats were fed either regular chow or a cafeteria diet to induce obesity. A sub-group of the obese animals then underwent either sham surgery or SG.

RESULTS

Following a 4-week recovery period, SG rats weighed significantly less than obese or sham-operated rats. Improvements in glucose tolerance and insulin sensitivity also occurred in the SG group, but these were not always statistically significant. We measured the intracellular lipid content of liver samples and found that obese rats showed signs of non-alcoholic fatty liver disease, which were significantly ameliorated by SG. There were significantly higher glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) responses to a standard mixed meal in the SG group, as well as paradoxically higher glucagon secretion.

CONCLUSION

These data highlight the need for more specific anti-glucagon antibodies to characterize the changes in proglucagon-derived peptide concentrations that occur following SG. Further studies are required to determine whether these peptides contribute to the therapeutic effects of SG.

Targeted delivery of nutraceuticals derived from food for the treatment of obesity and its related complications

Nutraceuticals which are abundant in foods have attracted much attention due to their bioactive activities of anti-obesity, anti-hyperlipidemia and anti-atherosclerosis. Unfortunately, the poor bioavailability severely undermines their envisioned benefits. Therefore, there is an urgent need to develop suitable delivery systems to promote the benefits of their biological activity. Targeted drug delivery system (TDDS) is a novel drug delivery system that can selectively concentrate drugs on targets in the body, improve the bioavailability of agents and reduce side effects. This emerging drug delivery system provides a new strategy for the treatment of obesity with nutraceuticals and would be a promising alternative to be widely used in the food field. This review summarizes the recent studies on the application in the targeted delivery of nutraceuticals for treating obesity and its related complications, especially the available receptors and their corresponding ligands for TDDS and the evaluation methods of the targeting ability.

Cannabinoid receptor type 1 (CB1R) inhibits hypothalamic leptin signaling via β-arrestin1 in complex with TC-PTP and STAT3

Molecular interactions between anorexigenic leptin and orexigenic endocannabinoids, although of great metabolic significance, are not well understood. We report here that hypothalamic STAT3 signaling in mice, initiated by physiological elevations of leptin, is diminished by agonists of the cannabinoid receptor 1 (CB1R). Measurement of STAT3 activation by semi-automated confocal microscopy in cultured neurons revealed that this CB1R-mediated inhibition requires both T cell protein tyrosine phosphatase (TC-PTP) and β-arrestin1 but is independent of changes in cAMP. Moreover, β-arrestin1 translocates to the nucleus upon CB1R activation and binds both STAT3 and TC-PTP. Consistently, CB1R activation failed to suppress leptin signaling in β-arrestin1 knockout mice in vivo, and in neural cells deficient in CB1R, β-arrestin1 or TC-PTP. Altogether, CB1R activation engages β-arrestin1 to coordinate the TC-PTP-mediated inhibition of the leptin-evoked neuronal STAT3 response. This mechanism may restrict the anorexigenic effects of leptin when hypothalamic endocannabinoid levels rise, as during fasting or in diet-induced obesity.

Weight Loss Supplements

Being overweight or obese can predispose people to chronic diseases and metabolic disorders such as cardiovascular illnesses, diabetes, Alzheimer's disease, and cancer, which are costly public health problems and leading causes of mortality worldwide. Many people hope to solve this problem by using food supplements, as they can be self-prescribed, contain molecules of natural origin considered to be incapable of causing damage to health, and the only sacrifice they require is economic. The market offers supplements containing food plant-derived molecules (e.g., primary and secondary metabolites, vitamins, and fibers), microbes (probiotics), and microbial-derived fractions (postbiotics). They can control lipid and carbohydrate metabolism, reduce appetite (interacting with the central nervous system) and adipogenesis, influence intestinal microbiota activity, and increase energy expenditure. Unfortunately, the copious choice of products and different legislation on food supplements worldwide can confuse consumers. This review summarizes the activity and toxicity of dietary supplements for weight control to clarify their potentiality and adverse reactions. A lack of research regarding commercially available supplements has been noted. Supplements containing postbiotic moieties are of particular interest. They are easier to store and transport and are safe even for people with a deficient immune system.

Design, synthesis and biological evaluation of salicylanilides as novel allosteric inhibitors of human pancreatic lipase

Obesity is a growing global health problem and is associated with increased prevalence of many metabolic disorders, including diabetes, hypertension and cardiovascular disease. Pancreatic lipase (PL) has been validated as a key target for developing anti-obesity agents, owing to its crucial role in lipid digestion and absorption. In the past few decades, porcine PL (pPL) is always used as the enzyme source for screening PL inhibitors, which generate numerous pPL inhibitors but the potent inhibitors against human PL (hPL) are rarely reported. Herein, a series of salicylanilide derivatives were designed and synthesized, while their anti-hPL effects were assayed by a fluorescence-based biochemical approach. To investigate the structure-activity relationships of salicylanilide derivatives as hPL inhibitors in detail, structural modifications on three rings (A, B and C) of the salicylanilide skeleton were performed. Among all tested compounds, 2t and 2u were found possessing the most potent anti-PL activity, showing IC₅₀ values of 1.86 μM and 1.63 μM, respectively. Inhibition kinetic analyses suggested that both 2t and 2u could effectively inhibit hPL in a non-competitive manner, with the k_i value of 1.67 μM and 1.70 μM, respectively. Fluorescence quenching assays suggested that two inhibitors could quench the fluorescence of hPL via a static quenching procedure. Molecular docking simulations suggested that 2t and 2u could tightly bind on an allosteric site of hPL. Collectively, the structure-activity relationships of salicylanilide derivatives as hPL inhibitors were carefully investigated, while two newly identified reversible hPL inhibitors (2t and 2u) could be used as promising lead compounds to develop novel anti-obesity drugs.

The Effect of Catgut Embedding at Acupoints Versus Nonacupoints in Abdominal Obesity: Protocol for a Multicenter, Double-Blind, 16-Week Randomized Controlled Trial

BACKGROUND

Obesity is an increasing problem worldwide. The effective treatments for obesity mainly include diet, physical activity, behavioral intervention, pharmacotherapy, and bariatric surgery, which all have certain limitations. As a specific type of acupuncture therapy, acupoint catgut embedding (ACE) has gained substantial attention in the management of obesity in recent years. Previous studies suggested that ACE may be an effective obesity treatment. However, the evidence for the efficacy of ACE in abdominal obesity (AO) remains inadequate due to the paucity of high-quality studies.

OBJECTIVE

This study aims to investigate the difference in the effectiveness of catgut embedding at acupoints and catgut embedding at nonacupoints in patients with AO and to further validate the efficacy and safety of ACE for AO.

METHODS

This is a multicenter, double-blind, 16-week randomized controlled trial. A total of 92 eligible participants with AO will be randomly divided into 2 groups (1:1 allocation ratio). The ACE group will receive catgut embedding at acupoints and the control group will receive catgut embedding at nonacupoints. The intervention will be performed every 2 weeks for a total of 6 sessions. Follow-up will be performed every 2 weeks for a total of 2 visits. The primary outcome is waist circumference. Secondary outcomes include body weight, BMI, hip circumference, and the visual analog scale of appetite. Upon the completion of the trial, we will evaluate the effect of catgut embedding at acupoints or nonacupoints on obesity indicators in patients with AO. For treatment outcomes, an intention-to-treat analysis will be performed.

RESULTS

The start of recruitment began in August 2019 and is expected to end in September 2023.

CONCLUSIONS

Although studies have been conducted to demonstrate the effectiveness of ACE in the treatment of obesity, the evidence for the efficacy of ACE in AO remains insufficient due to the quality of the studies. This rigorous normative randomized controlled trial will verify the effect of catgut embedding at acupoints or nonacupoints in patients with AO. The findings will provide credible evidence as to whether ACE is an effective and safe treatment for AO.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR1800016947; https://tinyurl.com/2p82257p.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/46863.

Navigating the Role of Anti-Obesity Agents Prior to Pregnancy: A Narrative Review

Utilization of anti-obesity agents is rising in reproductive-age females with some planning for future pregnancy. Lifestyle-induced weight loss has been shown to increase spontaneous conception rate, improve rates of fertility intervention complications, and decrease pregnancy comorbidities. However, the definitive role of assisting weight loss with medication prior to pregnancy remains to be established. The implications of anti-obesity agent used prior to pregnancy are explored in this narrative review, considering benefits of weight loss as well as available evidence for use and risks of anti-obesity agents prior to pregnancy.

Major Adverse Cardiovascular Events Among Obese Patients with Diabetes After Metabolic and Bariatric Surgery: a Meta-analysis of Matched Cohort and Prospective Controlled Studies with 122,361 Participates

PURPOSE

Metabolic and bariatric surgery (MBS) can exert effective function on glycemic control. The present study aimed to estimate the risk of MACE among obese patients with diabetes after MBS.

MATERIALS AND METHODS

Systematic search of PubMed, Embase, Medline, and Web of Science was performed for studies published before 20th February 2023. The odds ratio (OR) corresponding to the 95% confidence interval (95% CI) was used to assess the outcome. The statistical heterogeneity among studies was assessed with the Q-test and I2 statistics.

RESULTS

Fifteen cohort studies with 122,361 obese patients with diabetes were available for analysis. Our meta-analysis found significantly decreased morbidity and mortality of MACE (OR = 0.65, 95% CI = 0.59-0.72, I2 = 62.8% for morbidity, OR = 0.49, 95% CI = 0.36-0.67, I2 = 68.7% for mortality). Subgroup analysis revealed MBS decreased cerebrovascular disease, coronary artery disease, atrial fibrillation, heart failure, myocardial infarction, and stroke risk.

CONCLUSION

Our meta-analysis indicated that MBS for obese patients with diabetes is beneficial to decreasing MACE risk. Moreover, further studies estimating the functional effect may eventually provide a better and comprehensive understanding of the effect on different populations.

Poria cocos compounds targeting neuropeptide Y1 receptor (Y1R) for weight management: A computational ligand- and structure-based study with molecular dynamics simulations identified beta-amyrin acetate as a putative Y1R inhibitor

Poria cocos (PC) is a medicinal herb frequently used in weight-loss clinical trials, however the mechanisms by which its compounds target orexigenic receptors including the neuropeptide Y1 receptor (Y1R) remain largely unknown. This study aimed to screen PC compounds for favourable pharmacokinetics profiles and examine their molecular mechanisms targeting Y1R. Forty-three PC compounds were systematically sought from pharmacological databases and docked with Y1R (PDB: 5ZBQ). By comparing the relative binding affinities, pharmacokinetics and toxicity profiles, we hypothesised that compounds designated PC1 3,4-Dihydroxybenzoic acid, PC8 Vanillic acid, PC40 1-(alpha-L-Ribofuranosyl)uracil, could be potential antagonists as they contact major residues Asn283 and Asp287, similar to various potent Y1R antagonists. In addition, PC21 Poricoic acid B, PC22 Poricoic acid G and PC43 16alpha,25-Dihydroxy-24-methylene-3,4-secolanosta-4(28),7,9(11)-triene-3,21-dioic acid, contacting Asn299, Asp104 and Asp200 proximal to the extracellular surface could also interfere with agonist binding by stabilising the extracellular loop (ECL) 2 of Y1R in a closed position. Owing to their selective interaction with Phe302, an important residue in binding of selective Y1R antagonists, PC12 beta-Amyrin acetate, PC26 3-Epidehydrotumulosic acid and PC27 Cerevisterol were proposed as putative antagonists. Following the consensus approach, PC12 beta-Amyrin acetate, PC26 3-Epidehydrotumulosic acid and PC27 Cerevisterol were identified as candidate compounds due to their high affinities (-12.2, -11.0 and -10.8 kcal, respectively), high drug-likeness and low toxicity profiles. Trajectory analyses and energy contributions of PC12-Y1R complex further confirmed their structural stability and favourable binding free energies, highlighting the feasibility and possible development of PC12 beta-Amyrin acetate as a future Y1R inhibitor.

Modulation of the Microbiome-Fat-Liver Axis by Lactic Acid Bacteria: A Potential Alleviated Role in High-Fat-Diet-Induced Obese Mice

The major characteristics of obesity are abnormal lipid metabolism, chronic inflammation, and imbalanced gut microbiota. It has been reported that lactic acid bacteria (LAB) possess potential for alleviating obesity, considering which the strain-specific functions and diverse mechanisms and the roles and mechanisms of various LAB are worthy of investigation. This study aimed to validate and investigate the alleviating effects and underlying mechanisms of three LAB strains, Lactiplantibacillus plantarum NCUH001046 (LP), Limosilactobacillus reuteri NCUH064003, and Limosilactobacillus fermentum NCUH003068 (LF), in high-fat-diet-induced obese mice. The findings demonstrated that the three strains, particularly LP, suppressed body weight gain and fat deposition; ameliorated lipid disorders, liver and adipocyte morphology, and chronic low-grade inflammation; and reduced lipid synthesis via activating the adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling pathway. In addition, LP and LF decreased the enrichment of bacteria positively correlated with obesity, like Mucispirillum, Olsenella, and Streptococcus, but facilitated the growth of beneficial bacteria negatively correlated with obesity, like Roseburia, Coprococcus, and Bacteroides, along with increasing the short-chain fatty acid levels. It is deduced that the underlying alleviating mechanism of LP was to modulate the hepatic AMPK signaling pathway and gut microbiota by the microbiome-fat-liver axis to alleviate obesity development. In conclusion, as a diet supplement, LP has promising potential in obesity prevention and treatment.

Role of cholecystokinin in satiation: a systematic review and meta-analysis

The aim of this review was to examine: (1) the ability of cholecystokinin (CCK) or analogues of CCK to influence satiation and changes in body weight generally and (2) the efficacy of CCK in influencing satiation and eating behaviour specifically at physiological levels of dosing. A systematic review of the literature was performed following the PRISMA 2020 guidelines in five electronic databases investigating the effect of exogenous CCK or analogues on satiation and body weight. A meta-analysis of studies that infused CCK and measured satiation via changes in food/energy intake was also conducted. A total of 1054 studies were found using the search terms which were reduced to fifteen studies suitable for inclusion. Of the twelve studies measuring the effect on the weight of food ingested or energy intake, eleven showed a decrease. An analogue of CCK which can be administered orally failed to produce any weight loss at 24 weeks. The meta-analysis found the effect of CCK on satiation dosed at physiological levels was significant with a standardised mean difference of 0·57 (95 % CI 0·30, 0·85, P < 0·0001). By comparison, CCK dosed at higher, pharmacological levels also had a significant effect with a standardised mean difference of 0·91 (95 % CI 0·46, 1·36, P < 0·0001). Eight of the ten studies in the meta-analysis combined CCK infusion with some means to facilitate stomach distension. The present review found evidence that at both physiological and pharmacological levels of dosing CCK has a significant effect on satiation but no evidence for weight loss over the long term.

The treatment of obesity in children and adolescents: consensus position statement of the Italian society of pediatric endocrinology and diabetology, Italian Society of Pediatrics and Italian Society of Pediatric Surgery

This Position Statement updates the different components of the therapy of obesity (lifestyle intervention, drugs, and surgery) in children and adolescents, previously reported in the consensus position statement on pediatric obesity of the Italian Society of Pediatric Endocrinology and Diabetology and the Italian Society of Pediatrics. Lifestyle intervention is the first step of treatment. In children older than 12 years, pharmacotherapy is the second step, and bariatric surgery is the third one, in selected cases. Novelties are available in the field of the medical treatment of obesity. In particular, new drugs demonstrated their efficacy and safety and have been approved in adolescents. Moreover, several randomized control trials with other drugs are in process and it is likely that some of them will become available in the future. The increase of the portfolio of treatment options for obesity in children and adolescents is promising for a more effective treatment of this disorder.

Combination anti-obesity medications to effectively treat bariatric surgery weight regain at an academic obesity center

Background

Combination anti-obesity medications (AOMs) to treat postoperative bariatric surgery weight regain have limited data on their use in the clinical setting. Understanding the optimal treatment protocol in this cohort will maximize weight loss outcomes.

Methods

A retrospective review of bariatric surgery patients (N = 44) presenting with weight regain at a single academic multidisciplinary obesity center who were prescribed AOM(s) plus intensive lifestyle modification for 12 months.

Results

Age: 28-76 years old, 93% female, mean weight 110.2 ± 20.3 kg, BMI 39.7 ± 7.4 kg/m2, presenting 5.2 ± 1.6 years post-bariatric surgery [27 (61.4%), 14 (31.8%), and 3 (6.8%) laparoscopic Roux-en-Y gastric bypass (RYGB), laparoscopic vertical sleeve gastrectomy (VSG), and open RYGB, respectively], with 15.1 ± 11.1 kg mean weight gain from nadir. Mean weight loss after medical intervention at 3-, 6-, and 12-month time points was 4.4 ± 4.6 kg, 7.3 ± 7.0 kg, and 10.7 ± 9.2 kg, respectively. At 12 months, individuals prescribed 3 or more AOMs lost more weight than those prescribed one (-14.5 ± 9.0 kg vs. -4.9 ± 5.7 kg, p < 0.05) irrespective of age, gender, number of comorbidities, initial weight or BMI, type of surgery, or GLP1 use. RYGB patients lost less weight overall (7.4% vs. 14.8% VSG respectively; p < 0.05).

Conclusions

Combination AOMs may be needed to achieve optimal weight loss results to treat post-operative weight regain.

Opioid growth factor receptor promotes adipose tissue thermogenesis via enhancing lipid oxidation

The thermogenic brown and beige adipocytes consume fatty acids and generate heat to maintain core body temperature in the face of cold challenges. Since their validated presence in humans, the activation of thermogenic fat has been an attractive target for treating obesity and related metabolic diseases. Here, we reported that the opioid growth factor receptor (Ogfr) was highly expressed in adipocytes and promoted thermogenesis. The mice with genetic deletion of Ogfr in adipocytes displayed an impaired capacity to counter environmental cold challenges. Meanwhile, Ogfr ablation in adipocytes led to reduced fatty acid oxidation, enhanced lipid accumulation, impaired glucose tolerance, and exacerbated tissue inflammation under chronic high-fat diet (HFD)-fed conditions. At the cellular level, OGFr enhanced the production of mitochondrial trifunctional protein subunit α (MTPα) and also interacted with MTPα, thus promoting fatty acid oxidation. Together, our study demonstrated the important role of OGFr in fatty acid metabolism and adipose thermogenesis.

Obesity wars: may the smell be with you

Classically, the regulation of energy balance has been based on central and peripheral mechanisms sensing energy, nutrients, metabolites, and hormonal cues. Several cellular mechanisms at central level, such as hypothalamic AMP-activated protein kinase (AMPK), integrate this information to elicit counterregulatory responses that control feeding, energy expenditure, and glucose homeostasis, among other processes. Recent data have added more complexity to the homeostatic regulation of metabolism by introducing, for example, the key role of "traditional" senses and sensorial information in this complicated network. In this regard, current evidence is showing that olfaction plays a key and bidirectional role in energy homeostasis. Although nutritional status dynamically and profoundly impacts olfactory sensitivity, the sense of smell is involved in food appreciation and selection, as well as in brown adipose tissue (BAT) thermogenesis and substrate utilization, with some newly described actors, such as olfactomedin 2 (OLFM2), likely playing a major role. Thus, olfactory inputs are contributing to the regulation of both sides of the energy balance equation, namely, feeding and energy expenditure (EE), as well as whole body metabolism. Here, we will review the current knowledge and advances about the role of olfaction in the regulation of energy homeostasis.

Association between obesity, inflammation and insulin resistance: Insights into signaling pathways and therapeutic interventions

Obesity, a metabolic disorder, is becoming a worldwide epidemic that predominantly increases the risk for various diseases including metabolic inflammation, insulin resistance, and cardiovascular diseases. However, the mechanisms that link obesity with other metabolic diseases are not completely understood. In obesity, various inflammatory pathways that cause inflammation in adipose tissue of an obese individual become activated and exacerbate the disease. Obesity-induced low-grade metabolic inflammation perturbates the insulin signaling pathway and leads to insulin resistance. Researchers have identified several pathways that link the impairment of insulin resistance through obesity-induced inflammation like activation of Nuclear factor kappa B (NF-κB), suppressor of cytokine signaling (SOCS) proteins, cJun-N-terminal Kinase (JNK), Wingless-related integration site (Wnt), and Toll-like receptor (TLR) signaling pathways. In this review article, the published studies have been reviewed to identify the potential and influential role of different signaling pathways in the pathogenesis of obesity-induced metabolic inflammation and insulin resistance along with the discussion on potential therapeutic strategies. Therapies targeting these signaling pathways show improvements in metabolic diseases associated with obesity, but require further testing and confirmation through clinical trials.

Child and adolescent obesity

The prevalence of child and adolescent obesity has plateaued at high levels in most high-income countries and is increasing in many low-income and middle-income countries. Obesity arises when a mix of genetic and epigenetic factors, behavioural risk patterns and broader environmental and sociocultural influences affect the two body weight regulation systems: energy homeostasis, including leptin and gastrointestinal tract signals, operating predominantly at an unconscious level, and cognitive-emotional control that is regulated by higher brain centres, operating at a conscious level. Health-related quality of life is reduced in those with obesity. Comorbidities of obesity, including type 2 diabetes mellitus, fatty liver disease and depression, are more likely in adolescents and in those with severe obesity. Treatment incorporates a respectful, stigma-free and family-based approach involving multiple components, and addresses dietary, physical activity, sedentary and sleep behaviours. In adolescents in particular, adjunctive therapies can be valuable, such as more intensive dietary therapies, pharmacotherapy and bariatric surgery. Prevention of obesity requires a whole-system approach and joined-up policy initiatives across government departments. Development and implementation of interventions to prevent paediatric obesity in children should focus on interventions that are feasible, effective and likely to reduce gaps in health inequalities.

Integrative genomic analyses in adipocytes implicate DNA methylation in human obesity and diabetes

DNA methylation variations are prevalent in human obesity but evidence of a causative role in disease pathogenesis is limited. Here, we combine epigenome-wide association and integrative genomics to investigate the impact of adipocyte DNA methylation variations in human obesity. We discover extensive DNA methylation changes that are robustly associated with obesity (N = 190 samples, 691 loci in subcutaneous and 173 loci in visceral adipocytes, P < 1 × 10-7). We connect obesity-associated methylation variations to transcriptomic changes at >500 target genes, and identify putative methylation-transcription factor interactions. Through Mendelian Randomisation, we infer causal effects of methylation on obesity and obesity-induced metabolic disturbances at 59 independent loci. Targeted methylation sequencing, CRISPR-activation and gene silencing in adipocytes, further identifies regional methylation variations, underlying regulatory elements and novel cellular metabolic effects. Our results indicate DNA methylation is an important determinant of human obesity and its metabolic complications, and reveal mechanisms through which altered methylation may impact adipocyte functions.

Potential of omega-3 and conjugated fatty acids to control microglia inflammatory imbalance elicited by obesogenic nutrients

High-fat diet-induced obesity detrimentally affects brain function by inducing chronic low-grade inflammation. This neuroinflammation is, at least in part, likely to be mediated by microglia, which are the main immune cell population in the brain. Microglia express a wide range of lipid-sensitive receptors and their activity can be modulated by fatty acids that cross the blood-brain barrier. Here, by combining live cell imaging and FRET technology we assessed how different fatty acids modulate microglia activity. We demonstrate that the combined action of fructose and palmitic acid induce Ikβα degradation and nuclear translocation of the p65 subunit nuclear factor kB (NF-κB) in HCM3 human microglia. Such obesogenic nutrients also lead to reactive oxygen species production and LynSrc activation (critical regulators of microglia inflammation). Importantly, short-time exposure to omega-3 (EPA and DHA), CLA and CLNA are sufficient to abolish NF-κB pathway activation, suggesting a potential neuroprotective role. Omega-3 and CLA also show an antioxidant potential by inhibiting reactive oxygen species production, and the activation of LynSrc in microglia. Furthermore, using chemical agonists (TUG-891) and antagonists (AH7614) of GPR120/FFA4, we demonstrated that omega-3, CLA and CLNA inhibition of the NF-κB pathway is mediated by this receptor, while omega-3 and CLA antioxidant potential occurs through different signaling mechanisms.

Metabolic and bariatric surgery and obesity pharmacotherapy for cancer prevention: current status and future possibilities

Obesity is a chronic, relapsing, progressive disease of excess adiposity that increases the risk of developing at least 13 types of cancer. This report provides a concise review of the current state of the science regarding metabolic and bariatric surgery and obesity pharmacotherapy related to cancer risk. Meta-analyses of cohort studies report that metabolic and bariatric surgery is independently associated with a lower risk of incident cancer than nonsurgical obesity care. Less is known regarding the cancer-preventive effects of obesity pharmacotherapy. The recent approval and promising pipeline of obesity drugs will provide the opportunity to understand the potential for obesity therapy to emerge as an evidence-based cancer prevention strategy. There are myriad research opportunities to advance our understanding of how metabolic and bariatric surgery and obesity pharmacotherapy may be used for cancer prevention.

Bariatric Surgery and Incident Heart Failure: a Propensity Score Matched Nationwide Cohort Study

BACKGROUND

Bariatric surgery results in significant weight loss and a reduction in the incidence of cardiovascular disease in patients with obesity; however, relatively little research considers its effect on the incidence of heart failure (HF). We aimed to determine whether bariatric surgery reduces the incidence of HF in patients with obesity, compared to non-surgical management.

METHODS

A propensity-score matched, retrospective cohort study using patients records from the nationwide Clinical Practice Research Database (CPRD) was conducted. 3052 patients who received bariatric surgery were matched with 3052 patients who did not, according to propensity to receive bariatric surgery, determined through a logistic regression model. Patients were eligible if >18 years old, BMI > 35 kg/m², and no prior diagnosis of HF. The pre-defined primary endpoint was the development of new HF, and secondary endpoints were all-cause mortality and hospitalisations due to HF.

RESULTS

Patients who received bariatric surgery had a significantly lower incidence of new HF (hazard ratio 0.45, 95% confidence interval 0.28-0.73, p = 0.0011) and all-cause mortality (hazard ratio 0.56, 95% confidence interval 0.38-0.83, p = 0.0036).

CONCLUSIONS

This study provides evidence of lower rates of HF and all-cause mortality in patients who undergo bariatric surgery, compared to propensity-score matched controls. Future studies to understand the mechanism(s) involved in this reduction and explore the lifetime benefits in high-risk cohorts are paramount.

Evaluation of Some Safety Parameters of Dual Histamine H3 and Sigma-2 Receptor Ligands with Anti-Obesity Potential

Many studies have shown the high efficacy of histamine H₃ receptor ligands in preventing weight gain. In addition to evaluating the efficacy of future drug candidates, it is very important to assess their safety profile, which is established through numerous tests and preclinical studies. The purpose of the present study was to evaluate the safety of histamine H₃/sigma-2 receptor ligands by assessing their effects on locomotor activity and motor coordination, as well as on the cardiac function, blood pressure, and plasma activity of certain cellular enzymes. The ligands tested at a dose of 10 mg/kg b.w. did not cause changes in locomotor activity (except for KSK-74) and did not affect motor coordination. Significant reductions in blood pressure were observed after the administration of compounds KSK-63, KSK-73, and KSK-74, which seems logically related to the increased effect of histamine. Although the results of in vitro studies suggest that the tested ligands can block the human ether-a-go-go-related gene (hERG) potassium channels, they did not affect cardiac parameters in vivo. It should be noted that repeated administration of the tested compounds prevented an increase in the activity of alanine aminotransferase (AlaT) and gamma-glutamyl transpeptidases (gGT) observed in the control animals fed a palatable diet. The obtained results show that the ligands selected for this research are not only effective in preventing weight gain but also demonstrate safety in relation to the evaluated parameters, allowing the compounds to proceed to the next stages of research.

Preventing high-fat diet-induced obesity and related metabolic disorders by hydrodynamic transfer of Il-27 gene

BACKGROUND AND OBJECTIVES

Interleukin-27 (IL-27) is a multifaceted heterodimer cytokine that exerts both pro-inflammatory and anti-inflammatory effects under different physiological conditions. IL-27 signaling plays a role in promoting energy expenditure through enhanced thermogenesis. The objective of the study is to determine the functional role of IL-27 in regulating weight gain, and glucose and lipid homeostasis in mice fed a high-fat diet (HFD).

METHODS

C57BL/6 mice were hydrodynamically transferred with pLIVE-IL-27 plasmids to achieve elevated level of IL-27 in blood and then kept on a HFD for 8 weeks. The impacts of Il-27 gene transfer on HFD-induced weight gain, adiposity, hepatic lipid accumulation, insulin resistance, glucose homeostasis and the mRNA levels of genes responsible for lipogenesis, glucose homeostasis and proinflammation were assessed by methods of biochemistry, histology, and molecular biology.

RESULTS

Hydrodynamic gene transfer of Il-27 gene resulted in a peak level of serum IL-27 in mice at 14.5 ng/ml 24 h after gene transfer followed by a sustained level at 2 ng/ml. The elevated level of IL-27 blocked HFD-induced fat accumulation and weight gain without reducing food intake. It also prevented metabolic abnormities of liver steatosis and insulin resistance. IL-27 overexpression promoted expression of major thermogenic genes in brown adipose tissues; and attenuated chronic inflammation and macrophage infiltration into white adipose tissues.

CONCLUSIONS

The results demonstrate that regulation of IL-27 level could be an effective strategy for management of obesity and obesity-related metabolic diseases.

Mexican Ancestral Foods (Theobroma cacao, Opuntia ficus indica, Persea americana and Phaseolus vulgaris) Supplementation on Anthropometric, Lipid and Glycemic Control Variables in Obese Patients: A Systematic Review and Meta-Analysis

Diet containing Mexican ancestral foods such as cocoa, nopal, avocado, and common bean have been individually reported to have beneficial effects on obesity and comorbidities. Methods: A systematic review and meta-analysis on the effect of Mexican ancestral foods on the anthropometric, lipid, and glycemic control variables in obese patients was performed following PRISMA guidelines. Data were analyzed using a random-effects model. Results: We selected 4664 articles from an initial search, of which only fifteen studies satisfied the inclusion criteria. Data for 1670 participants were analyzed: 843 in the intervention group and 827 in the control group. A significant reduction in body mass index (mean difference: −0.80 (−1.31 to −0.30)) (95% confidence interval), p = 0.002, heterogeneity I2 = 92% was showed after the ingestion of cocoa, nopal, avocado, or common bean. The mean difference for body weight was −0.57 (−1.93 to 0.79), waist of circumference: −0.16 (−2.54 to −2.21), total cholesterol: −5.04 (−11.5 to 1.08), triglycerides: −10.11 (−27.87 to 7.64), fasting glucose: −0.81 (−5.81 to 4.19), and insulin: −0.15 (−0.80 to 0.50). Mexican ancestral food supplementation seems to improve anthropometric, lipid, and glycemic control variables in obesity; however, more randomized controlled trials are needed to have further decisive evidence about dosage and method of supplementation and to increase the sample size.

Case report of PLXNA4 variant associated with hyper-response to phentermine/topiramate pharmacotherapy: Potential genetic basis for superior weight loss response?

Background

Once thought to be primarily a result of lifestyle, it is now known that obesity has significant genetic components. Dozens of genes have been linked to obesity, and office-based genetic testing for obesity-associated genes is now readily available. As both pharmacotherapy and genetic testing for obesity become more accessible, pharmacogenetic personalization is becoming a reality. In this case report, a patient with a PLXNA4 polymorphism had a superior weight loss response to phentermine/topiramate therapy than has previously been reported in the literature. Thus, variants in PLXNA4 may provide a genetic basis for this patient's superior response to weight loss pharmacotherapy and cardiovascular risk factor reduction.

Methods

In this case study, office-based genetic testing was utilized to identify the presence of variants in nearly 80 genes that have been linked to obesity in a patient who had hyper-responsive weight loss results on phentermine/topiramate pharmacotherapy.

Results

A variant of the PLXNA4 gene, which has known pathogenic variants linked to genetic obesity syndromes, was identified in this patient who had a superior weight loss response to phentermine/topiramate pharmacotherapy.

Conclusion

Due to overlapping molecular pathways, it is possible that PLXNA4 variants convey a superior weight-loss response and therefore superior cardiovascular risk factor reduction phentermine/topiramate therapy. Further studies are needed to examine the relationship between PLXNA4 variants and weight loss with phentermine/topiramate pharmacotherapy.

The Perspectives of Plant Natural Products for Mitigation of Obesity

Obesity is a metabolic disease caused by an imbalance between energy intake and consumption, which leads to excessive fat accumulation in adipose tissues [...].

Hormonal Gut-Brain Signaling for the Treatment of Obesity

The brain, particularly the hypothalamus and brainstem, monitors and integrates circulating metabolic signals, including gut hormones. Gut-brain communication is also mediated by the vagus nerve, which transmits various gut-derived signals. Recent advances in our understanding of molecular gut-brain communication promote the development of next-generation anti-obesity medications that can safely achieve substantial and lasting weight loss comparable to metabolic surgery. Herein, we comprehensively review the current knowledge about the central regulation of energy homeostasis, gut hormones involved in the regulation of food intake, and clinical data on how these hormones have been applied to the development of anti-obesity drugs. Insight into and understanding of the gut-brain axis may provide new therapeutic perspectives for the treatment of obesity and diabetes.

Scytosiphon lomentaria Extract Ameliorates Obesity and Modulates Gut Microbiota in High-Fat-Diet-Fed Mice

Scytosiphon lomentaria (SL) is a brown seaweed with antioxidant and anti-inflammatory properties; however, its effects on obesity are unknown. In this research, we investigated the anti-obesity properties and underlying mechanisms of the SL extract in vitro and in vivo. In 3T3-L1 preadipocytes, SL extract inhibited lipid accumulation, decreased the expression of Acc1, C/ebpa, Pparg mRNA and p-ACC1, and increased the expression of Ucp1 mRNA, UCP1 and p-AMPK. In animal experiments, mice were fed a chow diet, a high-fat diet (HF; 60% of calories as fat), and high-fat diet with SL extract (150 and 300 mg/kg body weight) for eight weeks (n = 10/group). SL extract reduced HF-induced weight gain, epididymal fat weight, fat cell size, LDL-C, leptin, fasting glucose, and glucose tolerance. In addition, SL extract had comparable effects on mRNA expression in WAT and liver to those observed in vitro, thereby inhibiting p-ACC1/ACC1 and increasing p-AMPK/AMPK and UCP1 expression. Furthermore, SL extract decreased HF-induced Firmicutes/Bacteroidetes ratio and reversed HF-reduced Bacteroides spp., Bacteroides vulgatus, and Faecalibacterium prausnitzii. These findings suggest that SL extract can aid in weight loss in mice fed a high-fat diet by altering adipogenic and thermogenic pathways, as well as gut microbiota composition.

Approaches to addressing the rise in obesity levels

Levels of obesity and overweight are increasing globally, with affected individuals often experiencing health issues and reduced quality of life. The pathogenesis of obesity is complex and multifactorial, and effective solutions have been elusive. In this Viewpoint, experts in the fields of medical therapy, adipocyte biology, exercise and muscle, bariatric surgery, genetics, and public health give their perspectives on current and future progress in addressing the rising prevalence of obesity.