Centrally Acting Agents for Obesity: Past, Present, and Future

A polyphenol fraction from Rosa multiflora var. platyphylala reduces body fat in overweight humans through appetite suppression - a randomized, double-blind, placebo-controlled trial

BACKGROUND

Rosa species are rich sources of polyphenols with physiological functions. In this study a polyphenol-rich Rosa multiflora (var. platyphylala) petal extract (RoseFit™) was investigated for weight loss in humans.

METHODS

In a randomized, placebo-controlled, parallel-group, double-blind clinical trial seventy overweight male and female subjects (20-50 years) with body mass index (BMI) 25-30 kg/m2 were randomly allocated to the active treatment group (RoseFit) and placebo group in a 1:1 ratio. The subjects received 300 mg capsules twice daily for 12 weeks. The primary efficacy outcome measures included body weight, BMI, and body composition, as determined using Dual-energy X-ray absorptiometry (DEXA). Secondary measures consisted of serum lipid profile and appetite marker (leptin and ghrelin) analyses. Safety analyses included biochemical and hematological assessments.

RESULTS

At the end of the study, a marked reduction in body weight (-1.20 ± 2.62 kg, p < 0.05) and BMI from baseline was observed in the RoseFit group. In addition, the body fat % (RoseFit = -1.69 ± 2.59%, placebo = 0.96 ± 3.21%; p < 0.001) and fat mass (RoseFit = -1.75 ± 1.80 kg, placebo = 1.61 ± 3.82 kg; p < 0.001) were significantly abated in RoseFit group. Importantly, the lean mass was maintained during the intervention. RoseFit ingestion significantly increased the serum leptin levels compared to the placebo (4.85%; p < 0.05). Further, RoseFit group showed reduction in the hunger hormone ghrelin level (2.27%; p < 0.001) from baseline to the end of study, compared to the placebo. The subjective evaluation of appetite using visual analog scale (VAS) questionnaires further confirmed the appetite-suppression effects of RoseFit. The lipid profile significantly improved in RoseFit-treated subjects. No serious adverse events were observed during the study, indicating the tolerability of RoseFit.

CONCLUSIONS

Supplementation with RoseFit significantly impacts body weight management and can thus be a potential nutraceutical ingredient for sustainable weight loss.

TRIAL REGISTRATION

CTRI/2019/10/021584 dated 09/10/2019.

Research on the mechanism of regulating spleen-deficient obesity in rats by bawei guben huashi jiangzhi decoction based on multi-omics analysis

ETHNOPHARMACOLOGY RELEVANCE

Bawei Guben Huashi Jiangzhi Decoction (BGHJ), a traditional Chinese compound formula, comprises eight Chinese medicinal herbs: Codonopsis Radix, Atractylodis Macrocephalae Rhizoma, Cassiae Semen, Lysimachiae Herba, Edgeworthiae Gardner Flos, Oryzae Semen cum Monasco, Nelumbinis Folium, and Alismatis Rhizoma. It has the therapeutic effects of improving digestive and absorptive functions of the gastrointestinal tract, reducing cholesterol levels, and helping to lose weight. Therefore, BGHJ is mainly used to treat spleen-deficient obesity (SDO) clinically.

AIM OF THE STUDY

This study aims to examine the efficacy and mechanism of BGHJ in a model of SDO in rats, as well as the potentially involved constituents entering the blood and differential metabolites.

METHODS

The SDO rat model was replicated utilizing a high-fat and high-sugar diet in conjunction with exhaustive swimming. Subsequently, the rats were subjected to a six-week intervention comprising varying dosages of BGHJ and a positive control, orlistat. To evaluate the efficacy of BGHJ on SDO model rats, we first measured the rats' body weight, body surface temperature, spleen index, as well as biochemical indicators in the serum and colon, and then assessed the pathological state of the colon and liver. Afterward, we analyzed the 16S rDNA gut microbiota, non-targeted serum metabolomics, and serum pharmacology to study the main active components of BGHJ and its action mechanism against SDO model rats. In addition, we constructed a network diagram for overall visualization and analysis, and experimentally verified the predicted results. Finally, we used quantitative polymerase chain reaction (qPCR) to detect the gene expression of proopiomelanocortin (POMC) and neuropeptide Y (NPY) indicators in rat hypothalamic neurons. We quantitatively targeted the detection of neurotransmitters dopamine (DA), acetylcholine (Ach), 5-hydroxytryptamine (5-HT), and noradrenaline (NA) in rat hypothalamus.

RESULTS

The results demonstrated that all dosage regimens of BGHJ exhibited the capacity to moderately modulate parameters including body weight, surface temperature, spleen index, total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK), 5-HT, interleukin 6 (IL-6) and interleukin 17 (IL-17), while concurrently reducing hepatic lipid droplet deposition and restoring intestinal integrity. Subsequent experimental results showed that we successfully identified 27 blood components of BGHJ and identified 52 differential metabolites in SDO model rats. At the same time, the experiment proved that BGHJ could effectively inhibit the metabolic pathway of arachidonic acid. In addition, BGHJ can also restore the intestinal microbiota composition of SDO model rats. Finally, we also found that BGHJ could regulate the expression of hypothalamic neurons and neurotransmitters.

CONCLUSIONS

The research revealed the main active ingredients of BGHJ and its mechanism against SDO model rats through gut microbiota, non-target serum metabolomics, and serum drug chemistry.

Characterization of a new selective glucocorticoid receptor modulator with anorexigenic activity

Obesity, a worldwide epidemic, leads to various metabolic disorders threatening human health. In response to stress or fasting, glucocorticoid (GC) levels are elevated to promote food intake. This involves GC-induced expression of the orexigenic neuropeptides in agouti-related protein (AgRP) neurons of the hypothalamic arcuate nucleus (ARC) via the GC receptor (GR). Here, we report a selective GR modulator (SGRM) that suppresses GR-induced transcription of genes with non-classical glucocorticoid response elements (GREs) such as Agrp-GRE, but not with classical GREs, and via this way may serve as a novel anti-obesity agent. We have identified a novel SGRM, 2-O-trans-p-coumaroylalphitolic acid (Zj7), a triterpenoid extracted from the Ziziphus jujube plant, that selectively suppresses GR transcriptional activity in Agrp-GRE without affecting classical GREs. Zj7 reduces the expression of orexigenic genes in the ARC and exerts a significant anorexigenic effect with weight loss in both high fat diet-induced obese and genetically obese db/db mouse models. Transcriptome analysis showed that Zj7 represses the expression of a group of orexigenic genes including Agrp and Npy induced by the synthetic GR ligand dexamethasone (Dex) in the hypothalamus. Taken together, Zj7, as a selective GR modulator, showed beneficial metabolic activities, in part by suppressing GR activity in non-classical GREs in orexigenic genes. This study demonstrates that a potential anorexigenic molecule may allow GRE-specific inhibition of GR transcriptional activity, which is a promising approach for the treatment of metabolic disorders.

Shedding light on weight loss: A narrative review of medications for treating obesity

Obesity and overweight are the major risk factors for numerous chronic diseases, including cardiovascular diseases such as heart disease and stroke, which are the leading causes of death worldwide. The prevalence of obesity has dramatically risen in both developed and developing countries, making it a significant public health concern and a global crisis. Despite lifestyle modifications being the first-line treatment, the high risk of relapse has led to a growing interest in non-invasive pharmacotherapeutic interventions to achieve and maintain weight loss and reverse the growth of the obesity epidemic. Cardiovascular diseases and cancer account for the highest mortality rates among other comorbidities associated with obesity and overweight. Excess and abnormally deposited adipose tissue secretes various inflammatory mediators, leading to cardiovascular diseases and cancers. Weight loss of 5-10% significantly reduces cardiometabolic risk. Medications currently approved in the USA for long-term management of obesity are orlistat, naltrexone, bupropion, phentermine/topiramate, and Glucagon Like Peptide-1 (GLP-1) agonists such as liraglutide and semaglutide. The benefit-to-risk of medications, comorbidities, and individual responses should guide the treatment decisions. The article provides a comprehensive overview and discussion of several weight loss medications used previously and currently, including their efficacy, mechanisms of action, and side effects.

Popularity of Surgical and Pharmacological Obesity Treatment Methods Searched by Google Users: the Retrospective Analysis of Google Trends Statistics in 2004-2022

PURPOSE

Many individuals search for obesity treatment options on the Internet. We aimed to analyze the popularity of pharmacological and surgical obesity treatment methods searched by Google users.

MATERIAL AND METHODS

We used Google Trends to identify topics representing the following: recommended surgical methods (n = 9), recommended pharmacological methods (n = 10), and not recommended pharmacological methods (n = 34). The data was generated for 2004-2022 and 2020-2022. Relative search volume (RSV) was adjusted using "Gastric bypass surgery" as a benchmark. We analyzed the geographical and temporal trends of the topics.

RESULTS

In 2004-2022, the topics representing recommended surgical methods numerically gained the most popularity among Google users, but in 2020-2022 the recommended drugs exceeded other obesity treatment methods. The most popular individual topics since 2004 were "flaxseed," "Spirulina," "Carnitine," "Bariatric surgery," and "Orlistat." The most dynamic increases of searches since 2004 were observed for "Sleeve gastrectomy," "Curcumin," "Psyllium," and "Bupropion/Naltrexon." Since 2018, topics representing GLP-1 analogs such as "Semaglutide" and "Saxenda" revealed exponential increases in RSV, causing that "Semaglutide" to become the fourth most popular topic in 2020-2022.

CONCLUSIONS

Google users across the world were the most interested in topics representing bariatric surgery, but recently recommended drugs for the treatment of obesity gained the most attention. The most popular individual topics were dietary supplements with uncertain effects on weight loss.

TAAR1 agonists improve glycemic control, reduce body weight and modulate neurocircuits governing energy balance and feeding

OBJECTIVE

Metabolic Syndrome, which can be induced or exacerbated by current antipsychotic drugs (APDs), is highly prevalent in schizophrenia patients. Recent preclinical and clinical evidence suggest that agonists at trace amine-associated receptor 1 (TAAR1) have potential as a new treatment option for schizophrenia. Intriguingly, preclinical tudies have also identified TAAR1 as a novel regulator of metabolic control. Here we evaluated the effects of three TAAR1 agonists, including the clinical development candidate ulotaront, on body weight, metabolic parameters and modulation of neurocircuits implicated in homeostatic and hedonic feeding.

METHODS

Effects of TAAR1 agonists (ulotaront, RO5166017 and/or RO5263397) on body weight, food intake and/or metabolic parameters were investigated in rats fed a high-fat diet (HFD) and in a mouse model of diet-induced obesity (DIO). Body weight effects were also determined in a rat and mouse model of olanzapine-, and corticosterone-induced body weight gain, respectively. Glucose tolerance was assessed in lean and diabetic db/db mice and fasting plasma glucose and insulin examined in DIO mice. Effects on gastric emptying were evaluated in lean mice and rats. Drug-induced neurocircuit modulation was evaluated in mice using whole-brain imaging of c-fos protein expression.

RESULTS

TAAR1 agonists improved oral glucose tolerance by inhibiting gastric emptying. Sub-chronic administration of ulotaront in rats fed a HFD produced a dose-dependent reduction in body weight, food intake and liver triglycerides compared to vehicle controls. In addition, a more rapid reversal of olanzapine-induced weight gain and food intake was observed in HFD rats switched to ulotaront or RO5263397 treatment compared to those switched to vehicle. Chronic ulotaront administration also reduced body weight and improved glycemic control in DIO mice, and normalized corticosterone-induced body weight gain in mice. TAAR1 activation increased neuronal activity in discrete homeostatic and hedonic feeding centers located in the dorsal vagal complex and hypothalamus with concurrent activation of several limbic structures.

CONCLUSION

The current data demonstrate that TAAR1 agonists, as a class, not only lack APD-induced metabolic liabilities but can reduce body weight and improve glycemic control in rodent models. The underlying mechanisms likely include TAAR1-mediated peripheral effects on glucose homeostasis and gastric emptying as well as central regulation of energy balance and food intake.

Sunflower seed extract supplementation reduces body fat in adults with obesity: A double-blind, randomized, placebo-controlled trial

Obesity is an important public health problem and socioeconomic burden. We hypothesized that an intake of sunflower seed extract (SUN-CA) would decrease body fat and then investigated the effects and safety of SUN-CA intake on body fat in adults with obesity as an option for obesity treatment. In this double-blind, randomized, placebo-controlled study, 100 adults with body mass indices of 25 to 31.9 kg/m2 were assigned to groups that received SUN-CA (n = 50) or a placebo (n = 50) and received 1 tablet/day containing 500 mg of SUN-CA or the placebo over a 12-week period. The primary endpoint was the change in mass and percentage of body fat. The group that received SUN-CA daily showed decreases in body fat mass greater than those in the placebo group (-0.9 ± 1.8 kg vs. -0.1 ± 1.4 kg, P = .043). In addition, body weight, body mass index, and hip circumference improved after the intake of SUN-CA relative to the changes in the placebo group. There was no intergroup differences in the prevalence of adverse events. The accumulation of excess body fat improved through the intake of 500 mg/day of SUN-CA containing 100 mg of chlorogenic acids for 12 weeks in adults with obesity without causing serious adverse side effects. SUN-CA could be an effective and safe management option for obesity. The trial was registered at Clinical Research Information Service (CRIS: https://cris.nih.go.kr/cris/index/index.do) as KCT0005733.

Gut liver brain axis in diseases: the implications for therapeutic interventions

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract, liver, and nervous systems. In the past few decades, breakthrough progress has been made in the gut liver brain axis, mainly through understanding its formation mechanism and increasing treatment strategies. In this review, we discuss various complex networks including barrier permeability, gut hormones, gut microbial metabolites, vagus nerve, neurotransmitters, immunity, brain toxic metabolites, β-amyloid (Aβ) metabolism, and epigenetic regulation in the gut-liver-brain axis. Some therapies containing antibiotics, probiotics, prebiotics, synbiotics, fecal microbiota transplantation (FMT), polyphenols, low FODMAP diet and nanotechnology application regulate the gut liver brain axis. Besides, some special treatments targeting gut-liver axis include farnesoid X receptor (FXR) agonists, takeda G protein-coupled receptor 5 (TGR5) agonists, glucagon-like peptide-1 (GLP-1) receptor antagonists and fibroblast growth factor 19 (FGF19) analogs. Targeting gut-brain axis embraces cognitive behavioral therapy (CBT), antidepressants and tryptophan metabolism-related therapies. Targeting liver-brain axis contains epigenetic regulation and Aβ metabolism-related therapies. In the future, a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

Role of diet and exercise in aging, Alzheimer's disease, and other chronic diseases

Alzheimer's disease (AD) is a progressive neurodegenerative disease, characterized by memory loss and multiple cognitive impairments. Genetic mutations cause a small proportion (1-2%) of early-onset AD, with mutations in amyloid precursor protein (APP), presenilin 1 (PS1) and presenilin 2 (PS2). Major contributing factors of late-onset AD are ApoE4 genotype, traumatic brain injury, diabetes, obesity, hypertension, cardiovascular conditions, in addition to lifestyle factors, such as unhealthy diet and lack of physical exercise. Disease progression can be delayed and/or prevented to a greater extent by adopting healthy lifestyle with balanced and antioxidant enriched diet and daily exercise. The interaction and interplay of diet, exercise, age, and pharmacological interventions holds a crucial role in the progression, pathogenesis and management of AD and its comorbidities, including diabetes, obesity, hypertension and cardiovascular conditions. Antioxidant enriched diet contributes to brain health, glucose control, weight management, and cardiovascular well-being. Regular exercise removes toxins including free radicals and enhances insulin sensitivity, and supports cardiovascular function. In the current article, we discussed, the role of diet, and exercise in aging, AD and other conditions including diabetes, obesity, hypertension, cardiovascular conditions. This article also highlights the impact of medication, socioeconomic and lifestyle factors, and pharmacological interventions. These aspects were discussed in different races and ethnic groups in Texas, and the US.

Biobehavioral susceptibility for obesity in childhood: Behavioral, genetic and neuroimaging studies of appetite

Modern food environments are conducive to overeating and weight gain, but not everyone develops obesity. One reason for this may be that individuals differ in appetitive characteristics, or traits, that manifest early in life and go on to influence their behavioral susceptibility to gain and maintain excess weight. Classic studies showing that eating behavior in children can be measured by behavioral paradigms such as tests of caloric compensation and eating in the absence of hunger inspired the development and validation of psychometric instruments to assess appetitive characteristics in children and infants. A large body of evidence now suggests that food approach traits increase obesity risk, while food avoidant traits, such as satiety responsiveness, decrease obesity risk. Twin studies and genetic association studies have demonstrated that appetitive characteristics are heritable, consistent with a biological etiology. However, family environment factors are also influential, with mounting evidence suggesting that genetic and environmental risk factors interact and correlate with consequences for child eating behavior and weight. Further, neuroimaging studies are revealing that individual differences in responses to visual food cues, as well as to small tastes and larger amounts of food, across a number of brain regions involved in reward/motivation, cognitive control and other functions, may contribute to individual variation in appetitive behavior. Growing evidence also suggests that variation on psychometric measures of appetite is associated with regional differences in brain structure, and differential patterns of resting state functional connectivity. Large prospective studies beginning in infancy promise to enrich our understanding of neural and other biological underpinnings of appetite and obesity development in early life, and how the interplay between genetic and environmental factors affects appetitive systems. The biobehavioral susceptibility model of obesity development and maintenance outlined in this narrative review has implications for prevention and treatment of obesity in childhood.

Amphetamines in child medicine: a review of ClinicalTrials.gov

Background: Globally, the use of amphetamines as therapeutic agents in pediatric medicine is a crucial area of concern, especially given the population's vulnerability. Methods: On 6 August 2023, a search was conducted on ClinicalTrials.gov using "amphetamine" as the keyword. Two independent examiners screened trials against set criteria, including a focus on amphetamine, completion status, an interventional approach, and included children. Ongoing or observational studies were excluded. Data extracted from the qualified trials encompassed primary objectives, participant counts, study duration, and outcomes, with the aim of analyzing children disorders treated by amphetamine. Results: On 6 August 2023, a search of the ClinicalTrials.gov database with the term "amphetamines" identified 179 clinical trials. After extensive exclusion criteria, 19 trials were ultimately selected for analysis. The predominant condition under investigation was attention deficit hyperactivity disorder (ADHD), present in 84.2% of studies. Key study characteristics included: phase 4 trials (36.8%), randomized allocation (63.2%), and the parallel intervention model (42.1%). Masking techniques varied, with no masking in 42.1% of studies, and double and quadruple masking both accounting for 21.1%. Geographically, 78.9% of the studies' participants were from the United States. Conclusion: This study highlights the notable therapeutic potential of amphetamines in pediatric ADHD populations and emphasizes the importance of recognizing potential side effects and addiction risks. As pharmacogenomics offers the prospect of personalized treatments, there is potential to increase therapeutic efficacy and decrease adverse reactions. It is vital to balance these benefits against the inherent risks, understanding the need for continued research to optimize the use of amphetamines in medicine.

Tirzepatide for Weight Loss: Can Medical Therapy "Outweigh" Bariatric Surgery?

The worldwide prevalence of obesity has been increasing progressively over the past few decades and is predicted to continue to rise in coming years. Unfortunately, this epidemic is also affecting increasing rates of children and adolescents, posing a serious global health concern. Increased adiposity is associated with various comorbidities and increased mortality risk. Conversely, weight loss and chronic weight management are associated with improvements in overall morbidity and mortality. The pathophysiology of obesity is multifactorial with complex interactions between genetic and environmental factors. The foundation of most weight loss plans is lifestyle modification including dietary change and exercise. However, lifestyle modification alone is often insufficient to achieve clinically meaningful weight loss due to physiological mechanisms that limit weight reduction and promote weight regain. Therefore, research has focused on adjunctive pharmacotherapy to enable patients to achieve greater weight loss and improved chronic weight maintenance compared to lifestyle modification alone. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) are incretin hormone analogs that have proven effective for the management of type 2 diabetes mellitus as well as obesity and overweight. Tirzepatide is a novel "twincretin" that functions as a dual glucose-dependent insulinotropic polypeptide and GLP-1 RA. Tirzepatide was recently approved by the Food and Drug Administration for the management of type 2 diabetes. Similar to previously approved GLP-1RAs, weight loss is a common side effect of tirzepatide which prompted research focused on its use as a primary weight loss therapy. Although this drug has not yet been approved as an antiobesity medication, there are several phase 3 clinical trials that have demonstrated superior weight loss efficacy compared with previously approved medications. This review article will discuss the discovery and mechanism of tirzepatide, as well as the completed and ongoing trials that may lead to its approval as an adjunctive pharmacotherapy for weight loss.

Recent advancements in pharmacological strategies to modulate energy balance for combating obesity

The prevalence of obesity along with its related metabolic diseases has increased globally in recent decades. Obesity originates from a heterogeneous physiological state, which is further complicated by the influence of factors such as genetic, behavioural, and environmental. Lifestyle interventions including exercise and diet have limited success, necessitating the development of pharmacological approaches. Mechanistically, strategies target either reducing energy intake or increasing consumption through metabolism boosting. Current drugs lower energy intake via inducing satiety or inhibiting substrate absorption, while targeting mitochondria or cytosolic energy sensors has shown limited success due to toxicity. Nonshivering thermogenesis (NST) has provided hope for activating these processes selectively without significant side effects. The internet-based marketing of plant-based formulations for enhancing metabolism has surged. This review compiles scientific articles, magazines, newspapers, and online resources on anti-obesity drug development. Combination therapy of metabolic boosters and established anti-obesity compounds appears to be a promising future approach that requires further research.

Structural analysis of the dual agonism at GLP-1R and GCGR

Glucagon-like peptide-1 receptor (GLP-1R) and glucagon receptor (GCGR), two members of class B1 G protein-coupled receptors, play important roles in glucose homeostasis and energy metabolism. They share a high degree of sequence homology but have different functionalities. Unimolecular dual agonists of both receptors developed recently displayed better clinical efficacies than that of monotherapy. To study the underlying molecular mechanisms, we determined high-resolution cryo-electron microscopy structures of GLP-1R or GCGR in complex with heterotrimeric Gs protein and three GLP-1R/GCGR dual agonists including peptide 15, MEDI0382 (cotadutide) and SAR425899 with variable activating profiles at GLP-1R versus GCGR. Compared with related structures reported previously and supported by our published pharmacological data, key residues responsible for ligand recognition and dual agonism were identified. Analyses of peptide conformational features revealed a difference in side chain orientations within the first three residues, indicating that distinct engagements in the deep binding pocket are required to achieve receptor selectivity. The middle region recognizes extracellular loop 1 (ECL1), ECL2, and the top of transmembrane helix 1 (TM1) resulting in specific conformational changes of both ligand and receptor, especially the dual agonists reshaped ECL1 conformation of GLP-1R relative to that of GCGR, suggesting an important role of ECL1 interaction in executing dual agonism. Structural investigation of lipid modification showed a better interaction between lipid moiety of MEDI0382 and TM1-TM2 cleft, in line with its increased potency at GCGR than SAR425899. Together, the results provide insightful information for the design and development of improved therapeutics targeting these two receptors simultaneously.

Neurochemical Basis of Inter-Organ Crosstalk in Health and Obesity: Focus on the Hypothalamus and the Brainstem

Precise neural regulation is required for maintenance of energy homeostasis. Essential to this are the hypothalamic and brainstem nuclei which are located adjacent and supra-adjacent to the circumventricular organs. They comprise multiple distinct neuronal populations which receive inputs not only from other brain regions, but also from circulating signals such as hormones, nutrients, metabolites and postprandial signals. Hence, they are ideally placed to exert a multi-tier control over metabolism. The neuronal sub-populations present in these key metabolically relevant nuclei regulate various facets of energy balance which includes appetite/satiety control, substrate utilization by peripheral organs and glucose homeostasis. In situations of heightened energy demand or excess, they maintain energy homeostasis by restoring the balance between energy intake and expenditure. While research on the metabolic role of the central nervous system has progressed rapidly, the neural circuitry and molecular mechanisms involved in regulating distinct metabolic functions have only gained traction in the last few decades. The focus of this review is to provide an updated summary of the mechanisms by which the various neuronal subpopulations, mainly located in the hypothalamus and the brainstem, regulate key metabolic functions.

Uncovering CNS access of lipidated exendin-4 analogues by quantitative whole-brain 3D light sheet imaging

Peptide-based drug development for CNS disorders is challenged by poor blood-brain barrier (BBB) penetrability of peptides. While acylation protractions (lipidation) have been successfully applied to increase circulating half-life of therapeutic peptides, little is known about the CNS accessibility of lipidated peptide drugs. Light-sheet fluorescence microscopy (LSFM) has emerged as a powerful method to visualize whole-brain 3D distribution of fluorescently labelled therapeutic peptides at single-cell resolution. Here, we applied LSFM to map CNS distribution of the clinically relevant GLP-1 receptor agonist (GLP-1RA) exendin-4 (Ex4) and lipidated analogues following peripheral administration. Mice received an intravenous dose (100 nmol/kg) of IR800 fluorophore-labelled Ex4 (Ex4), Ex4 acylated with a C16-monoacid (Ex4_C16MA) or C18-diacid (Ex4_C18DA). Other mice were administered C16MA-acylated exendin 9-39 (Ex9-39_C16MA), a selective GLP-1R antagonist, serving as negative control for GLP-1R mediated agonist internalization. Two hours post-dosing, brain distribution of Ex4 and analogues was predominantly restricted to the circumventricular organs, notably area postrema and nucleus of the solitary tract. Ex4_C16MA and Ex9-39_C16MA also distributed to the paraventricular hypothalamic nucleus and medial habenula. Notably, Ex4_C18DA was detected in deeper-lying brain structures such as dorsomedial/ventromedial hypothalamic nuclei and the dentate gyrus. Similar CNS distribution maps of Ex4-C16MA and Ex9-39_C16MA suggest that brain access of lipidated Ex4 analogues is independent on GLP-1 receptor internalization. The cerebrovasculature was devoid of specific labelling, hence not supporting a direct role of GLP-1 RAs in BBB function. In conclusion, peptide lipidation increases CNS accessibility of Ex4. Our fully automated LSFM pipeline is suitable for mapping whole-brain distribution of fluorescently labelled drugs.

Glucagon-modified Liposomes Delivering Thyroid Hormone for Anti-obesity Therapy

BACKGROUND

Thyroid hormones (active form T3) are naturally potent compounds that influence energy expenditure, cholesterol metabolism, and fat oxidation. T3 would be an effective anti-obesity drug if it would not be delivered to the heart and bones, which leads to serious side effects, such as cardiovascular and bone thyrotoxicity, muscle wasting, and so on.

METHODS

In this study, we designed a targeted drug delivery system that is a glucagon-modified liposome to deliver T3 to the liver and adipose tissues.

RESULTS

The liposomes exhibited excellent properties, including uniform nanoscale particle size, good physicochemical stability, and adequate drug release behavior. More importantly, the glucagon-modified liposomes were enriched in the liver, which minimized the undesired bone and cardiovascular thyrotoxicity of T3. Compared to the control group, T3-loading glucagon-modified liposomes could effectively decrease body weight, reverse hepatic steatosis, and correct hyperlipidemia and hyperglycemia in ob/ob mice, without the undesired cardiovascular and bone thyrotoxicity.

CONCLUSION

These findings indicate that delivery of thyroid hormone by glucagon-modified liposomes may provide an effective strategy for anti-obesity therapy.

Naringenin and β-carotene convert human white adipocytes to a beige phenotype and elevate hormone- stimulated lipolysis

Introduction

Naringenin, a peroxisome proliferator-activated receptor (PPAR) activator found in citrus fruits, upregulates markers of thermogenesis and insulin sensitivity in human adipose tissue. Our pharmacokinetics clinical trial demonstrated that naringenin is safe and bioavailable, and our case report showed that naringenin causes weight loss and improves insulin sensitivity. PPARs form heterodimers with retinoic-X-receptors (RXRs) at promoter elements of target genes. Retinoic acid is an RXR ligand metabolized from dietary carotenoids. The carotenoid β-carotene reduces adiposity and insulin resistance in clinical trials. Our goal was to examine if carotenoids strengthen the beneficial effects of naringenin on human adipocyte metabolism.

Methods

Human preadipocytes from donors with obesity were differentiated in culture and treated with 8µM naringenin + 2µM β-carotene (NRBC) for seven days. Candidate genes involved in thermogenesis and glucose metabolism were measured as well as hormone-stimulated lipolysis.

Results

We found that β-carotene acts synergistically with naringenin to boost UCP1 and glucose metabolism genes including GLUT4 and adiponectin, compared to naringenin alone. Protein levels of PPARα, PPARγ and PPARγ-coactivator-1α, key modulators of thermogenesis and insulin sensitivity, were also upregulated after treatment with NRBC. Transcriptome sequencing was conducted and the bioinformatics analyses of the data revealed that NRBC induced enzymes for several non-UCP1 pathways for energy expenditure including triglyceride cycling, creatine kinases, and Peptidase M20 Domain Containing 1 (PM20D1). A comprehensive analysis of changes in receptor expression showed that NRBC upregulated eight receptors that have been linked to lipolysis or thermogenesis including the β1-adrenergic receptor and the parathyroid hormone receptor. NRBC increased levels of triglyceride lipases and agonist-stimulated lipolysis in adipocytes. We observed that expression of RXRγ, an isoform of unknown function, was induced ten-fold after treatment with NRBC. We show that RXRγ is a coactivator bound to the immunoprecipitated PPARγ protein complex from white and beige human adipocytes.

Discussion

There is a need for obesity treatments that can be administered long-term without side effects. NRBC increases the abundance and lipolytic response of multiple receptors for hormones released after exercise and cold exposure. Lipolysis provides the fuel for thermogenesis, and these observations suggest that NRBC has therapeutic potential.

Pharmacological Treatments and Natural Biocompounds in Weight Management

The obesity pandemic is one of society’s most urgent public health concerns. One-third of the global adult population may fall under obese or overweight by 2025, suggesting a rising demand for medical care and an exorbitant cost of healthcare expenditure in the coming years. Generally, the treatment strategy for obese patients is largely patient-centric and needs dietary, behavioral, pharmacological, and sometimes even surgical interventions. Given that obesity cases are rising in adults and children and lifestyle modifications have failed to produce the desired results, the need for medical therapy adjunct to lifestyle modifications is vital for better managing obesity. Most existing or past drugs for obesity treatment target satiety or monoamine pathways and induce a feeling of fullness in patients, while drugs such as orlistat are targeted against intestinal lipases. However, many medications targeted against neurotransmitters showed adverse events in patients, thus being withdrawn from the market. Alternatively, the combination of some drugs has been successfully tested in obesity management. However, the demand for novel, safer, and more efficacious pharmaceutical medicines for weight management does exist. The present review elucidates the current understanding of the available anti-obesity medicines of synthetic and natural origin, their main mechanisms of action, and the shortcomings associated with current weight management drugs.

Impact of the herbal medicine, Ephedra sinica stapf, on gut microbiota and body weight in a diet-induced obesity model

Obesity is a chronic metabolic disease caused by excessive body fat and has become a global public health problem. Evidence suggests that obesity and obesity-induced metabolic disorders are closely related to gut microbiota. Bupropion (BP), an antidepressant medicine, and Ephedra sinica Stapf [Ephedraceae; Ephedrae Herba], a herbal medicine, are sympathetic stimulants and have weight loss effects. However, to our best knowledge, no studies have simultaneously assessed the effects of drugs and herbal medicines on obesity and gut microbiota. This study aimed to determine the effects of BP and ES on weight loss and re-modulation of host gut microbiota. To test this hypothesis, we fed C57BL/6J mice with a high-fat diet supplemented with bupropion (BP; 30 mg/kg/day) and Ephedra sinica Stapf extract (ES; 150 mg/kg/day) via oral gavage for eight weeks. Further, we evaluated the effects of BP and ES on body weight and fat accumulation. In addition, we evaluated the effects of BP and ES on gut microbiota using 16S rRNA amplicon sequencing. Our results showed that weight loss was confirmed in both BP and ES; however, it was more pronounced in ES. ES changed the overall composition of the gut microbiota by restoring the relative abundance of Oscillospiraceae, Lachnospiraceae, and the Firmicutes/Bacteroidetes ratio, an indicator of gut microbiota dysbiosis. Nine amplicon sequence variants (ASVs) of the gut microbiome were significantly recovered by BP and ES treatment, of which eight ASVs correlated with body weight and fat accumulation. Additionally, three ASVs were significantly recovered by ES treatment alone. In conclusion, the anti-obesity effects of BP and ES, especially fat accumulation, are related to the regulation of gut microbiota. Moreover, ES had a greater influence on the gut microbiota than BP.

Semaglutide for Weight Loss: Was It Worth the Weight?

Obesity is a major public health issue with an increasing prevalence worldwide. Excess body fat is associated with various comorbidities, as well as increased overall mortality risk. The benefits of weight loss are evident by the reductions in morbidity and mortality. The foundation for most weight loss programs involves strict lifestyle modification, including dietary change and exercise. Unfortunately, many individuals struggle with weight loss and chronic weight management due to difficulty adhering to long-term lifestyle modification and the metabolic adaptations that promote weight regain. The use of adjunctive pharmacotherapy has been employed to help patients not only achieve greater weight loss than lifestyle modification alone but also to assist with long-term weight management. Historically, antiobesity drugs have produced only modest weight loss and required at least once daily administration. Glucagon-like peptide-1 (GLP-1), a hormone with significant effects on glycemic control and weight regulation, has been explored for use as adjunctive pharmacotherapy for weight loss. Semaglutide, a GLP-1 receptor agonist, was recently approved by the Food and Drug Administration for chronic weight management in adults with obesity or who are overweight. The approval came after the publication of the Semaglutide Treatment Effect in People with Obesity clinical trials. In these 68-week trials, semaglutide 2.4 mg was associated with significantly greater weight loss compared to placebo. Semaglutide differs from other GLP-1 receptor agonists by having a longer half-life and producing greater weight loss. This article provides an overview of the discovery and mechanism of action of semaglutide 2.4 mg, and the clinical trials that led to its approval.

The In Vitro Inhibitory Effect of Selected Asteraceae Plants on Pancreatic Lipase Followed by Phenolic Content Identification through Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS)

Pancreatic lipase (PNLIP, EC 3.1.1.3) plays a pivotal role in the digestion of dietary lipids, a metabolic pathway directly related to obesity. One of the effective strategies in obesity treatment is the inhibition of PNLIP, which is possible to be achieved by specific phenolic compounds occurring in high abundance in some plants. In this study, a multidisciplinary approach is presented investigating the PNLIP inhibitory effect of 33 plants belonging in the Asteraceae botanical family. In the first stage of the study, a rapid and cost-efficient PNLIP assay in a 96-microwell plate format was developed and important parameters were optimized, e.g., the enzyme substrate. Upon PNLIP assay optimization, aqueous and dichloromethane Asteraceae plant extracts were tested and a cut-off inhibition level was set to further analyze only the samples with a significant inhibitory effect (inhibitory rate > 40%), using an ultra-high-performance liquid chromatography hybrid quadrupole time-of-flight mass spectrometry (UHPLC-q-TOF-MS) method. Specifically, a metabolomic suspect screening was performed and 69 phenolic compounds were tentatively identified, including phenolic acids, flavonoids, flavonoid-3-O-glycosides, and flavonoid-7-O-glycosides, amongst others. In the case of aqueous extracts, phytochemicals known for inducing PNLIP inhibitory effect, e.g., compounds containing galloyl molecules or caffeoylquinic acids, were monitored in Chrysanthemum morifolium, Grindella camporum and Hieracium pilosella extracts. All in all, the presented approach combines in vitro bioactivity measurements to high-end metabolomics to identify phenolic compounds with potential medicinal and/or dietary applications.

Anti-obesity weight loss medications: Short-term and long-term use

As obesity prevalence increases, more and more drugs that assist with weight loss have been developed. Numerous weight loss drugs had been approved, but many have also been withdrawn based on their lack of efficacy as well as safety concerns. Initial approaches in developing weight loss drugs was by increasing physiological energy expenditure and suppressing the appetite. Subsequently, as more physiological mechanisms for weight gain has been unearthed, drugs targeting newly discovered receptors and/or enzymes have been introduced with improved safety profiles and fewer psychological adverse events. Additionally, drugs targeting hunger or satiety signaling have been actively studied, and have shown increased adoption by physicians. Studies have also evaluated drugs that target metabolic tissues-such as adipose tissue or muscle-to promote weight loss, however to-date nothing has carried on into clinical practice. Starting with a brief history of early obesity treatments, this review evaluates current weight loss pharmaceutical options based on their duration of therapy status.

Turning the clock forward: New pharmacological and non pharmacological targets for the treatment of obesity

AIMS

Obesity and its main metabolic complication, type 2 diabetes, have attained the status of a global pandemic; there is need for novel strategies aimed at treating obesity and preventing the development of diabetes. A healthy diet and exercise are basic for treatment of obesity but often not enough. Pharmacotherapy can be helpful in maintaining compliance, ameliorating obesity-related health risks, and improving quality of life. In the last two decades, the knowledge of central and peripheral mechanisms underlying homeostatic and hedonic aspects of food intake has significantly increased. Dysregulation of one or more of these components could lead to obesity.

DATA SYNTHESIS

In order to better understand how potential innovative treatment options can affect obesity, homeostatic and reward mechanisms that regulate energy balance has been firstly illustrated. Then, an overview of potential therapeutic targets for obesity, distinguished according to the level of regulation of feeding behavior, has been provided. Moreover, several non-drug therapies have been recently tested in obesity, such as non-invasive neurostimulation: Transcranial Magnetic Stimulation or Transcranial Direct Current Stimulation. All of them are promising for obesity treatment and are almost devoid of side effects, constituting a potential resource for the prevention of metabolic diseases.

CONCLUSIONS

The plethora of current anti-obesity therapies creates the unique challenge for physicians to customize the intervention, according to the specific obesity characteristics and the intervention side effect profiles; moreover, it allows multimodal approaches addressed to treat obesity and metabolic adaptation with complementary mechanisms.

The Role of Glp-1 Receptor Agonists in Insulin Resistance with Concomitant Obesity Treatment in Polycystic Ovary Syndrome

Insulin resistance is documented in clamp studies in 75% of women with polycystic ovary syndrome (PCOS). Although it is not included in the diagnostic criteria of PCOS, there is a crucial role of this metabolic impairment, which along with hormonal abnormalities, increase each other in a vicious circle of PCOS pathogenesis. Insulin resistance in this group of patients results from defects at the molecular level, including impaired insulin receptor-related signaling pathways enhanced by obesity and its features: Excess visceral fat, chronic inflammation, and reactive oxygen species. While lifestyle intervention has a first-line role in the prevention and management of excess weight in PCOS, the role of anti-obesity pharmacological agents in achieving and maintaining weight loss is being increasingly recognized. Glucagon-like peptide-1 receptor agonists (GLP1-RAs) not only act by reducing body weight but also can affect the mechanisms involved in insulin resistance, like an increasing expression of glucose transporters in insulin-dependent tissues, decreasing inflammation, reducing oxidative stress, and modulating lipid metabolism. They also tend to improve fertility either by increasing LH surge in hypothalamus-pituitary inhibition due to estrogen excess connected with obesity or decreasing too high LH levels accompanying hyperinsulinemia. GLP1-RAs seem promising for effective treatment of obese PCOS patients, acting on one of the primary causes of PCOS at the molecular level.

Molecular Imaging of Central Dopamine in Obesity: A Qualitative Review across Substrates and Radiotracers

Dopamine is a neurotransmitter that plays a crucial role in adaptive behavior. A wealth of studies suggests obesity-related alterations in the central dopamine system. The most direct evidence for such differences in humans comes from molecular neuroimaging studies using positron emission tomography (PET) and single-photon emission computed tomography (SPECT). The aim of the current review is to give a comprehensive overview of molecular neuroimaging studies that investigated the relation between BMI or weight status and any dopamine target in the striatal and midbrain regions of the human brain. A structured literature search was performed and a summary of the extracted findings are presented for each of the four available domains: (1) D2/D3 receptors, (2) dopamine release, (3) dopamine synthesis, and (4) dopamine transporters. Recent proposals of a nonlinear relationship between severity of obesity and dopamine imbalances are described while integrating findings within and across domains, after which limitations of the review are discussed. We conclude that despite many observed associations between obesity and substrates of the dopamine system in humans, it is unlikely that obesity can be traced back to a single dopaminergic cause or consequence. For effective personalized prevention and treatment of obesity, it will be crucial to identify possible dopamine (and non-dopamine) profiles and their functional characteristics.

Review article: role of glucagon-like peptide-1 receptor agonists in non-alcoholic steatohepatitis, obesity and diabetes-what hepatologists need to know

BACKGROUND

Non-alcoholic steatohepatitis (NASH) is characterised by hepatic lipid accumulation, cell injury, inflammation and fibrosis. Insulin resistance, a hallmark of type 2 diabetes (T2D) and obesity, is a key pathogenic driver of NASH. Other than difficult-to-maintain lifestyle changes, there are no approved treatments for NASH. Due to their effects on multiple pathophysiological processes, glucagon-like peptide-1 receptor agonists (GLP-1RAs) have been tested in disorders related to insulin resistance and metabolic defects.

AIMS

To summarise studies of GLP-1RAs relevant to the treatment of NASH.

METHODS

PubMed searches were performed and results were compiled.

RESULTS

Large trials with GLP-1RAs in T2D demonstrate highly effective glucose lowering, with body weight loss, and in some cases, reduced cardiovascular events and improved liver transaminases. The GLP-1RAs, liraglutide and semaglutide, were associated with clinically relevant, sustained body weight reduction in individuals with overweight or obesity and without T2D. In a phase II trial in NASH, liraglutide reduced metabolic dysfunction, insulin resistance and lipotoxicity in key organs associated with NASH pathogenesis. Furthermore, liraglutide and semaglutide led to histological resolution of NASH in ~40% to 60% of patients, although a statistically significant effect on fibrosis has not been confirmed. Regarding safety, GLP-1RAs are associated with gastrointestinal and gallbladder-related adverse events, with the latter perhaps related to weight loss. Meta-analyses do not indicate increased risk of acute pancreatitis, pancreatic cancer or other malignancies with GLP-1RAs.

CONCLUSIONS

These studies support the use of GLP-1RAs for the improvement of underlying metabolic dysfunction observed in NASH and suggest further long-term phase III trials are warranted.

The incretin/glucagon system as a target for pharmacotherapy of obesity

Obesity is a chronic, multifactorial, relapsing disease. Despite multicomponent lifestyle interventions, including pharmacotherapy, maintaining bodyweight loss is challenging for many people. The pathophysiology of obesity is complex, and currently approved pharmacotherapies only target a few of the many pathways involved; thus, single-targeting agents have limited efficacy. Proglucagon-derived peptides, glucagon, and the incretin hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), represent attractive targets for managing obesity and metabolic disorders because they may have direct roles in multiple mechanisms including satiety, energy homeostasis, and lipolytic activity. Unimolecular dual and triple agonists targeting glucagon and incretin hormone receptors have been shown to promote bodyweight loss, lower glucose levels, and reduce food intake in animal models of obesity. Multiple dual receptor agonists are in clinical development for the treatment of obesity, including GLP-1/GIP and GLP-1/glucagon receptor agonists. The extent to which glucagon contributes to treatment effects remains to be understood, but it may promote bodyweight loss by reducing food intake, while concomitant GLP-1 receptor agonism ensures normal glucose control. Further research is required to fully understand the molecular mechanisms of action and metabolic effects of both dual and triple receptor agonists.

Skeletal Muscle Microvascular Dysfunction in Obesity-Related Insulin Resistance: Pathophysiological Mechanisms and Therapeutic Perspectives

Obesity is a worrisomely escalating public health problem globally and one of the leading causes of morbidity and mortality from noncommunicable disease. The epidemiological link between obesity and a broad spectrum of cardiometabolic disorders has been well documented; however, the underlying pathophysiological mechanisms are only partially understood, and effective treatment options remain scarce. Given its critical role in glucose metabolism, skeletal muscle has increasingly become a focus of attention in understanding the mechanisms of impaired insulin function in obesity and the associated metabolic sequelae. We examined the current evidence on the relationship between microvascular dysfunction and insulin resistance in obesity. A growing body of evidence suggest an intimate and reciprocal relationship between skeletal muscle microvascular and glucometabolic physiology. The obesity phenotype is characterized by structural and functional changes in the skeletal muscle microcirculation which contribute to insulin dysfunction and disturbed glucose homeostasis. Several interconnected etiologic molecular mechanisms have been suggested, including endothelial dysfunction by several factors, extracellular matrix remodelling, and induction of oxidative stress and the immunoinflammatory phenotype. We further correlated currently available pharmacological agents that have deductive therapeutic relevance to the explored pathophysiological mechanisms, highlighting a potential clinical perspective in obesity treatment.

N-linoleyltyrosine ameliorates high-fat diet-induced obesity in C57BL/6 mice via cannabinoid receptor regulation

OBJECTIVES

N-linoleyltyrosine (NITyr) showed mild effects in preclinical studies. The research discussed the effect of NITyr on a high-fat diet (HFD) induced obese (DIO) mice, and preliminarily explored its mechanism.

METHODS

The DIO mice were established by feeding an HFD for 12 weeks and subsequently administrated orally with NITyr (30, 60 and 100 mg/kg) for four weeks. The indexes of serum and liver samples were determined by ELISA kit. The pathological status of adipose and liver were detected by HE staining. The factors related to energy and lipid metabolism were measured via western blot.

RESULTS

NITyr at 60 and 100 mg/kg/day suppressed the weight gain without affecting water and food intake. Accordingly, NITyr reduced adipose weight and the area of individual adipocytes and increased the number of adipocytes. Moreover, NITyr didn't affect the appetite-related indexes such as ghrelin, peptide YY and brain-derived neurotrophic factor. Besides, NITyr didn't affect other organ coefficients except for the liver. Correspondingly, NITyr reduced alanine aminotransferase and aspartate aminotransferase levels, yet didn't influence IL-1β and TNF-α levels, and the liver injury. The levels of triacylglycerol (TG), total cholesterol (TC), glucose, insulin, adiponectin and leptin in serum were assessed to evaluate the effect of NITyr on glucose and lipid metabolism. NITyr decreased the levels of TG, TC and glucose, and didn't affect insulin, adiponectin and leptin levels. Meanwhile, NITyr up-regulated p-AMPK and the cannabinoid receptor 2 (CB₂) expressions, and down-regulated PPAR, FAS and cannabinoid receptor 1 (CB₁) expressions.Overall, NITyr suppressed lipid accumulation via improving lipid and glucose metabolism involving CB₁ and CB₂ receptors.

Chronic Treatment With Psilocybin Decreases Changes in Body Weight in a Rodent Model of Obesity

BACKGROUND

There are currently relatively few effective pharmacological treatments for obesity, and existing ones may be associated with limiting side-effects. In the search for novel anti-obesity agents, drugs that modify central serotonergic systems have historically proven to be effective in promoting weight loss. Psilocin, which is rapidly metabolized from psilocybin, is an agonist at multiple serotonin receptors. In the present study we assessed the effects of psilocybin and a positive control (metformin) on changes in body weight in a rat model of obesity.

METHODS

Five groups of adult male rats were pre-conditioned with a cafeteria diet until obese (>600 g) and then treated with either psilocybin (0.1, 1, or 5 mg/kg, i.p.), metformin (300 mg/kg, p.o.) or vehicle control. Treatments were for 27 consecutive weekdays, and body weights and high calorie food intake were recorded daily. Fasting glucose levels were recorded after 11 days of treatment. At the end of treatment rats completed a glucose tolerance test, and multiple fat pads were dissected out to assess adiposity.

RESULTS

The medium dose psilocybin group had to be terminated from the study prematurely. Both the low and high dose psilocybin groups caused a significant decrease in changes in body weight compared to controls. The metformin group produced a greater decrease in change in body weight than either psilocybin groups or controls. Both high dose psilocybin and metformin decreased consumption of the high calorie diet, and exhibited decreased central adiposity.

CONCLUSION

Psilocybin demonstrated modest but significant effects on weight gain. Further study is recommended.

Treatment of Acquired Hypothalamic Obesity: Now and the Future

The hypothalamus is the centre of neuroendocrine regulation of energy homeostasis and appetite. Maldevelopment of, or damage to, the key hypothalamic nuclei disrupts the coordinated balance between energy intake and expenditure leading, to rapid and excessive weight gain. Hypothalamic obesity is compounded by a disruption of the hypothalamic-pituitary axis, sleep disruption, visual compromise, and neurological and vascular sequalae. Amongst suprasellar tumors, craniopharyngioma is the most common cause of acquired hypothalamic obesity, either directly or following surgical or radiotherapeutic intervention. At present, therapy is limited to strategies to manage obesity but with a modest and variable impact. Current approaches include optimizing pituitary hormone replacement, calorie restriction, increased energy expenditure through physical activity, behavioral interventions, pharmacotherapy and bariatric surgery. Current pharmacotherapeutic approaches include stimulants that increase energy consumption, anti-diabetic agents, hypothalamic-pituitary substitution therapy, octreotide, and methionine aminopeptidase 2 (MetAP2) inhibitors. Some pharmacological studies of hypothalamic obesity report weight loss or stabilization but reported intervention periods are short, and others report no effect. The impact of bariatric surgery on weight loss in hypothalamic obesity again is variable. Novel or combined approaches to manage hypothalamic obesity are thus required to achieve credible and sustained weight loss. Identifying etiological factors contributing hypothalamic obesity may lead to multi-faceted interventions targeting hyperphagia, insulin resistance, decreased energy expenditure, sleep disturbance, hypopituitarism and psychosocial morbidity. Placebo-controlled trials using current single, or combination therapies are required to determine the impact of therapeutic agents. A well-defined approach to defining the location of hypothalamic damage may support the use of future targeted therapies. Intranasal oxytocin is currently being investigated as an anorexogenic agent. Novel agents including those targeting pro-opimelanocortin-C and AgRP/NPY expressing neurons and the MC4 receptor may result in better outcomes. This article discusses the current challenges in the management of hypothalamic obesity in children and young people and future therapeutic approaches to increasing weight loss and quality of life in these patients.

A Single Dose of Ginkgo biloba Extract Induces Gene Expression of Hypothalamic Anorexigenic Effectors in Male Rats

Previous studies have shown that Ginkgo biloba extract (GbE) reduces food intake and body mass gain and regulates proteins related to lipid metabolism in obese rats. In ovariectomized rats, GbE restored the hippocampal and hypothalamic serotonergic system activity, favoring the spontaneous feeding decrement. Considering the promising hypophagic effect of GbE, this study aimed to investigate the effect of a single acute dose on hypothalamic pathways that regulate feeding behavior in male rats. Four-month-old Wistar male rats received either a single acute oral GbE dose (500 mg/kg) or vehicle. Food intake and body mass were measured after 1, 4, 12, and 24 h. Rats were euthanized, and hypothalami were removed for mRNA quantification of anorexigenic (POMC/CART) and orexigenic (AgRP/NPY) neuropeptides, leptin/serotonin receptors (5HT1A, 5HT1B, 5HT2C), and serotonin transporters. We also investigated POMC, 5-HT1B, and 5-HT2C protein levels. A single acute GbE dose induced the hypothalamic POMC, CART, and 5-HT2C gene expression but failed to modify orexigenic effectors. No alterations in food intake, body mass, and hypothalamic protein levels were observed. In summary, the present findings demonstrate the rapid stimulation of pivotal hypothalamic anorexigenic pathways in response to a single GbE administration, reinforcing the GbE hypophagic activity. However, more studies are necessary to evaluate its potential as an appetite modulator.

In search of an ideal drug for safer treatment of obesity: The false promise of pseudoephedrine

Obesity is a major public health problem worldwide. Only relatively few treatment options are, at present, available for the management of obese patients. Furthermore, treatment of obesity is affected by the widespread misuse of drugs and food supplements. Ephedra sinica is an old medicinal herb, commonly used in the treatment of respiratory tract diseases. Ephedra species contain several alkaloids, including pseudoephedrine, notably endowed with indirect sympathomimetic pharmacodynamic properties. The anorexigenic effect of pseudoephedrine is attributable primarily to the inhibition of neurons located in the hypothalamic paraventricular nucleus (PVN), mediating satiety stimuli. Pseudoephedrine influences lipolysis and thermogenesis through interaction with β3 adrenergic receptors and reduces fat accumulation through down-regulation of transcription factors related to lipogenesis. However, its use is associated with adverse events that involve to a large extent the cardiovascular and the central nervous system. Adverse events of pseudoephedrine also affect the eye, the intestine, and the skin, and, of relevance, sudden cardiovascular death related to dietary supplements containing Ephedra alkaloids has also been reported. In light of the limited availability of clinical data on pseudoephedrine in obesity, along with its significantly unbalanced risk/benefit profile, as well as of the psychophysical susceptibility of obese patients, it appears reasonable to preclude the prescription of pseudoephedrine in obese patients of any order and degree.

Treating the Chronic Disease of Obesity

Obesity is a treatable chronic disease. Primary care providers play an essential role in diagnosis, treatment, and comprehensive care of patients with obesity. In recent years, treatment approaches have rapidly evolved, increasing effective and safe therapies. In this review, we provide practical information on the care of patients with obesity with a focus on antiobesity pharmacotherapy within the context of currently available therapeutic modalities such as intensive lifestyle interventions and bariatric surgery.

Chitosan Oligosaccharide Ameliorates Metabolic Syndrome Induced by Overnutrition via Altering Intestinal Microbiota

Chitosan oligosaccharides (COS) play a prebiotic role in many ways, whereas its function on microbiota is not fully understood. In this study, the effects of COS on metabolic syndrome were initially investigated by testing changes in the physiological indicators after adding COS to the diet of mice with high fat (group H) and low fat (group L). The results showed that COS markedly inhibited the accumulation of body weight and liver fat induced by high-fat diet, as well as restored the elevated concentration of blood glucose and fasting insulin to normal levels. Next, changes of the murine intestinal microbiota were examined. The results exhibited that COS reduced with-in-sample diversity, while the between-sample microbial diversity enhanced. Specifically, COS enriched Clostridium paraputrificum and Clostridium ramosum in the mice on a high-fat diet, while the abundance of Clostridium cocleatum was reduced. As a comparison, Parabacteroides goldsteinii and Bacteroides uniformis increased their abundance in response to COS in the low-fat diet group. Noticeably, a large amount of Akkermansia muciniphila was enriched in both high-fat or low-fat diet groups. Among the differential fecal bacteria, Clostridium ramosume was found to be positively interacted with Faecalibacterim prausnitzii and Clostridium paraputrificum; Clostridium paraputrificum had a positive interactions with Lactococcus chungangensis and Bifidobacterium mongoliense, suggesting that COS probably ameliorate metabolic syndrome through the microbiota in view of the lipid-lowering effects of these interacted bacteria. Furthermore, the gene expression data revealed that COS improved the functions related to intestinal barrier and glucose transport, which could be the trigger and consequence of the variations in gut microbiota induced by COS. Additionally, correlation analysis found that intestinal bacteria are related to physiological parameters, which further supports the mediating role of gut microbiota in the beneficial effect of COS. In summary, our research results provide new evidence for the prebiotic effects of COS.

Hypothalamic control of interoceptive hunger

While energy balance is critical to survival, many factors influence food intake beyond caloric need or "hunger." Despite this, some neurons that drive feeding in mice are routinely referred to as "hunger neurons," whereas others are not. To understand how specific hypothalamic circuits control interoceptive hunger, we trained mice to discriminate fasted from sated periods. We then manipulated three hypothalamic neuronal populations with well-known effects on feeding while mice performed this task. While activation of ARC^AGRP neurons in sated mice caused mice to report being food-restricted, LH^VGAT neuron activation or LH^VGLUT2 neuron inhibition did not. In contrast, LH^VGAT neuron inhibition or LH^VGLUT2 neuron activation in fasted mice attenuated natural hunger, whereas ARC^AGRP neuron inhibition did not. Each neuronal population evoked distinct effects on food consumption and reward. After satiety- or sickness-induced devaluation, ARC^AGRP neurons drove calorie-specific feeding, while LH^VGAT neurons drove calorie-indiscriminate food intake. Our data support a role for ARC^AGRP neurons in homeostatic feeding and implicate them in driving a hunger-like internal state that directs behavior toward caloric food sources. Moreover, manipulations of LH circuits did not evoke hunger-like effects in sated mice, suggesting that they may govern feeding more related to reward, compulsion, or generalized consumption than to energy balance, but also that these LH circuits can be powerful negative appetite modulators in fasted mice. This study highlights the complexity of hypothalamic feeding regulation and can be used as a framework to characterize how other neuronal circuits affect hunger and identify potential therapeutic targets for eating disorders.

Thermogenic Fat: Development, Physiological Function, and Therapeutic Potential

The concerning worldwide increase of obesity and chronic metabolic diseases, such as T2D, dyslipidemia, and cardiovascular disease, motivates further investigations into preventive and alternative therapeutic approaches. Over the past decade, there has been growing evidence that the formation and activation of thermogenic adipocytes (brown and beige) may serve as therapy to treat obesity and its associated diseases owing to its capacity to increase energy expenditure and to modulate circulating lipids and glucose levels. Thus, understanding the molecular mechanism of brown and beige adipocytes formation and activation will facilitate the development of strategies to combat metabolic disorders. Here, we provide a comprehensive overview of pathways and players involved in the development of brown and beige fat, as well as the role of thermogenic adipocytes in energy homeostasis and metabolism. Furthermore, we discuss the alterations in brown and beige adipose tissue function during obesity and explore the therapeutic potential of thermogenic activation to treat metabolic syndrome.

Converging vulnerability factors for compulsive food and drug use

Highly palatable foods and substance of abuse have intersecting neurobiological, metabolic and behavioral effects relevant for understanding vulnerability to conditions related to food (e.g., obesity, binge eating disorder) and drug (e.g., substance use disorder) misuse. Here, we review data from animal models, clinical populations and epidemiological evidence in behavioral, genetic, pathophysiologic and therapeutic domains. Results suggest that consumption of highly palatable food and drugs of abuse both impact and conversely are regulated by metabolic hormones and metabolic status. Palatable foods high in fat and/or sugar can elicit adaptation in brain reward and withdrawal circuitry akin to substances of abuse. Intake of or withdrawal from palatable food can impact behavioral sensitivity to drugs of abuse and vice versa. A robust literature suggests common substrates and roles for negative reinforcement, negative affect, negative urgency, and impulse control deficits, with both highly palatable foods and substances of abuse. Candidate genetic risk loci shared by obesity and alcohol use disorders have been identified in molecules classically associated with both metabolic and motivational functions. Finally, certain drugs may have overlapping therapeutic potential to treat obesity, diabetes, binge-related eating disorders and substance use disorders. Taken together, data are consistent with the hypotheses that compulsive food and substance use share overlapping, interacting substrates at neurobiological and metabolic levels and that motivated behavior associated with feeding or substance use might constitute vulnerability factors for one another. This article is part of the special issue on 'Vulnerabilities to Substance Abuse'.

Legend of Weight Loss: a Crosstalk Between the Bariatric Surgery and the Brain

In recent years, plenty of researches have reported in obese individuals with abnormal brain processes implicated in homeostatic regulation, reward, emotion, memory, attention, and executive function in eating behaviors. Thus, treating obesity cannot remain "brainless." Behavioral and psychological interventions activate the food reward, attention, and motivation system, leading to minimal weight loss and high relapse rates. Pharmacotherapy is an effective weight loss method and regulate brain activity but with concerns about its brain function safety problems. Obesity surgery, the most effective therapy currently available for obesity, shows pronounced effects on brain activity, such as deactivation of reward and attention system, and activation of inhibition control toward food cues. In this review, we present an overview of alterations in the brain after the three common weight loss methods.

Selection of Antiobesity Medications Based on Phenotypes Enhances Weight Loss: A Pragmatic Trial in an Obesity Clinic

OBJECTIVE

Little is known about the predictors of response to obesity interventions.

METHODS

In 450 participants with obesity, body composition, resting energy expenditure, satiety, satiation, eating behavior, affect, and physical activity were measured by validated studies and questionnaires. These variables were used to classify obesity phenotypes. Subsequently, in a 12-month, pragmatic, real-world trial performed in a weight management center, 312 patients were randomly assigned to phenotype-guided treatment or non-phenotype-guided treatment with antiobesity medications: phentermine, phentermine/topiramate, bupropion/naltrexone, lorcaserin, and liraglutide. The primary outcome was weight loss at 12 months.

RESULTS

Four phenotypes of obesity were identified in 383 of 450 participants (85%): hungry brain (abnormal satiation), emotional hunger (hedonic eating), hungry gut (abnormal satiety), and slow burn (decreased metabolic rate). In 15% of participants, no phenotype was identified. Two or more phenotypes were identified in 27% of patients. In the pragmatic clinical trial, the phenotype-guided approach was associated with 1.75-fold greater weight loss after 12 months with mean weight loss of 15.9% compared with 9.0% in the non-phenotype-guided group (difference -6.9% [95% CI -9.4% to -4.5%], P < 0.001), and the proportion of patients who lost >10% at 12 months was 79% in the phenotype-guided group compared with 34% with non-phenotype-guided treatment group.

CONCLUSIONS

Biological and behavioral phenotypes elucidate human obesity heterogeneity and can be targeted pharmacologically to enhance weight loss.

Long-Term Efficacy and Safety of Anti-Obesity Treatment: Where Do We Stand?

PURPOSE OF REVIEW

As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of obesity, it is difficult to achieve an ideal weight or sustain the process of long-term weight loss. Therefore, the obesity control guidelines strongly recommend lifestyle interventions along with medical treatment for patients who are overweight. There is sufficient evidence supporting that pharmacotherapy in combination with behavior-based interventions can result in significant weight loss and improved cardiometabolism.

RECENT FINDINGS

Recent meta-analyses of new anti-obesity drugs and their weight-loss efficacy have shown that the overall placebo-subtracted weight reduction (%) for at least 12 months ranged from 2.9 to 6.8% for the following drugs: phentermine/topiramate (6.8%), liraglutide (5.4%), naltrexone/bupropion (4.0%), orlistat (2.9%), and lorcaserin (3.1%). However, very recently, on February 13, 2020, the US Food and Drug Administration (FDA) ordered the withdrawal of lorcaserin from markets, as a clinical trial to assess drug safety showed an increased risk of cancer. Currently, the anti-obesity medications that have been approved by the FDA for chronic weight management are orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide. However, they are costly and may have adverse effects in some individuals. Therefore, drug therapy should be initiated in obese individuals after weighing its benefits and risks. One of the strategies for long-term obesity control is that anti-obesity medications should be tailored for specific patients depending on their chronic conditions, comorbidities, and preferences.

Recent Advances in Hypertension: Intersection of Metabolic and Blood Pressure Regulatory Circuits in the Central Nervous System

Obesity represents the single greatest ongoing roadblock to improving cardiovascular health. Prolonged obesity is associated with fundamental changes in the integrative control of energy balance, including the development of selective leptin resistance, which is thought to contribute to obesity-associated hypertension, and adaptation of resting metabolic rate (RMR) when excess weight is reduced. Leptin and the melanocortin system within the hypothalamus contribute to the control of both energy balance and blood pressure. While the development of drugs to stimulate RMR and thereby reverse obesity through activation of the melanocortin system has been pursued, most of the resulting compounds simultaneously cause hypertension. Evidence supports the concept that although feeding behaviors, RMR, and blood pressure are controlled through mechanisms that utilize similar molecular mediators, these mechanisms exist in anatomically dissociable networks. New evidence supports a major change in molecular signaling within AgRP (Agouti-related peptide) neurons of the arcuate nucleus of the hypothalamus during prolonged obesity and the existence of multiple distinct subtypes of AgRP neurons that individually contribute to control of feeding, RMR, or blood pressure. Finally, ongoing work by our laboratory and others support a unique role for AT₁ (angiotensin II type 1 receptor) within one specific subtype of AgRP neuron for the control of RMR. We propose that understanding the unique biology of the AT₁-expressing, RMR-controlling subtype of AgRP neurons will help to resolve the selective dysfunctions in RMR control that develop during prolonged obesity and potentially point toward novel druggable antiobesity targets that will not simultaneously cause hypertension.

Antiobesity Effect of a Novel Herbal Formulation LI85008F in High-Fat Diet-Induced Obese Mice

A variety of natural products have been explored for their antiobesity potential and widely used to develop dietary supplements for the prevention of weight gain from excess body fat. In an attempt to find a natural antiobesity agent, this study was designed to evaluate the antiobesity activity of a novel herbal formulation LI85008F composed of extracts from three medicinal plants in high-fat diet- (HFD-) induced obese mice. After the thirteen-week oral administration of the test materials to mice, the body weight gain, whole-body fat mass, adipose tissue weight, and the expression levels of obesity-related proteins were measured. Our results indicated that LI85008F can suppress body weight gain and lower whole-body fat mass in HFD-induced obese mice. Significant decreases in epididymal and retroperitoneal fat mass were observed in LI85008F-treated groups compared with the HFD-fed control group (p < 0.05). Furthermore, the oral administration of LI85008F caused significant decreases in the expression level of adipogenic (C/EBPα and PPARγ) and lipogenic (ACC) markers and notable increases in the production level of thermogenetic (AMPKα, PGC1α and UCP1) and lipolytic (HSL) proteins. These findings suggest that LI85008F holds great promise for a novel herbal formulation with antiobesity activities, preventing body fat accumulation and altering lipid metabolism.

Bardet-Biedl syndrome: Weight patterns and genetics in a rare obesity syndrome

BACKGROUND

Bardet-Biedl syndrome (BBS) is a rare genetic disorder that severely inhibits primary cilia function. BBS is typified by obesity in adulthood, but pediatric weight patterns, and thus optimal periods of intervention, are poorly understood.

OBJECTIVES

To examine body mass differences by age, gender, and genotype in children and adolescents with BBS.

METHODS

We utilized the largest international registry of BBS phenotypes. Anthropometric and genetic data were obtained from medical records or participant/family interviews. Participants were stratified by age and sex categories. Genotype and obesity phenotype were investigated in a subset of participants with available data.

RESULTS

Height and weight measurements were available for 552 unique individuals with BBS. The majority of birth weights were in the normal range, but rates of overweight or obesity rapidly increased in early childhood, exceeding 90% after age 5. Weight z-scores in groups >2 years were above 2.0, while height z-scores approached 1.0, but were close to 0.0 in adolescents. Relative to those with the BBS10 genotype, the BBS1 cohort had a lower BMI z-score in the 2-5 and 6-11 age groups, with similar BMI z-scores thereafter. Children with biallelic loss of function (LOF) genetic variants had significantly higher BMI z-scores compared to missense variants.

CONCLUSION

Despite normal birth weight, most individuals with BBS experience rapid weight gain in early childhood, with high rates of overweight/obesity sustained through adolescence. Children with LOF variants are disproportionally affected. Our findings support the need for earlier recognition and initiation of weight management therapies in BBS.