Drug development strategies for the treatment of obesity: how to ensure efficacy, safety, and sustainable weight loss

Elucidating Drug-Like Compounds and Potential Mechanisms of Corn Silk (Stigma Maydis) against Obesity: A Network Pharmacology Study

Corn silk (Stigma Maydis) has been utilized as an important herb against obesity by Chinese, Korean, and Native Americans, but its phytochemicals and mechanisms(s) against obesity have not been deciphered completely. This study aimed to identify promising bioactive constituents and mechanism of action(s) of corn silk (CS) against obesity via network pharmacology. The compounds from CS were identified using Gas Chromatography Mass Spectrometry (GC-MS) and were confirmed ultimately by Lipinski's rule via SwissADME. The relationships of the compound-targets or obesity-related targets were confirmed by public bioinformatics. The signaling pathways related to obesity, protein-protein interaction (PPI), and signaling pathways-targets-bioactives (STB) were constructed, visualized, and analyzed by RPackage. Lastly, Molecular Docking Test (MDT) was performed to validate affinity between ligand(s) and protein(s) on key signaling pathway(s). We identified a total of 36 compounds from CS via GC-MS, all accepted by Lipinski's rule. The number of 36 compounds linked to 154 targets, 85 among 154 targets related directly to obesity-targets (3028 targets). Of the final 85 targets, we showed that the PPI network (79 edges, 357 edges), 12 signaling pathways on a bubble chart, and STB network (67 edges, 239 edges) are considered as therapeutic components. The MDT confirmed that two key activators (β-Amyrone, β-Stigmasterol) bound most stably to PPARA, PPARD, PPARG, FABP3, FABP4, and NR1H3 on the PPAR signaling pathway, also, three key inhibitors (Neotocopherol, Xanthosine, and β-Amyrone) bound most tightly to AKT1, IL6, FGF2, and PHLPP1 on the PI3K-Akt signaling pathway. Overall, we provided promising key signaling pathways, targets, and bioactives of CS against obesity, suggesting crucial pharmacological evidence for further clinical testing.

A Review on the Role of Food-Derived Bioactive Molecules and the Microbiota-Gut-Brain Axis in Satiety Regulation

Obesity is a chronic disease resulting from an imbalance between energy intake and expenditure. The growing relevance of this metabolic disease lies in its association with other comorbidities. Obesity is a multifaceted disease where intestinal hormones such as cholecystokinin (CCK), glucagon-like peptide 1 (GLP-1), and peptide YY (PYY), produced by enteroendocrine cells (EECs), have a pivotal role as signaling systems. Receptors for these hormones have been identified in the gut and different brain regions, highlighting the interconnection between gut and brain in satiation mechanisms. The intestinal microbiota (IM), directly interacting with EECs, can be modulated by the diet by providing specific nutrients that induce environmental changes in the gut ecosystem. Therefore, macronutrients may trigger the microbiota-gut-brain axis (MGBA) through mechanisms including specific nutrient-sensing receptors in EECs, inducing the secretion of specific hormones that lead to decreased appetite or increased energy expenditure. Designing drugs/functional foods based in bioactive compounds exploiting these nutrient-sensing mechanisms may offer an alternative treatment for obesity and/or associated metabolic diseases. Organ-on-a-chip technology represents a suitable approach to model multi-organ communication that can provide a robust platform for studying the potential of these compounds as modulators of the MGBA.

Negative Modulation of the Metabotropic Glutamate Receptor Type 5 as a Potential Therapeutic Strategy in Obesity and Binge-Like Eating Behavior

Obesity is a multifactorial disease, which in turn contributes to the onset of comorbidities, such as diabetes and atherosclerosis. Moreover, there are only few options available for treating obesity, and most current pharmacotherapy causes severe adverse effects, while offering minimal weight loss. Literature shows that metabotropic glutamate receptor 5 (mGluR5) modulates central reward pathways. Herein, we evaluated the effect of VU0409106, a negative allosteric modulator (NAM) of mGluR5 in regulating feeding and obesity parameters. Diet-induced obese C57BL/6 mice were treated for 14 days with VU0409106, and food intake, body weight, inflammatory/hormonal levels, and behavioral tests were performed. Our data suggest reduction of feeding, body weight, and adipose tissue inflammation in mice treated with high-fat diet (HFD) after chronic treatment with VU0409106. Furthermore, a negative modulation of mGluR5 also reduces binge-like eating, the most common type of eating disorder. Altogether, our results pointed out mGluR5 as a potential target for treating obesity, as well as related disorders.

Prevalence of Adverse Drug Events in Severely Obese Adults and Associated Factors: Clinical Trial Baseline Results

Drugs are the most widely used therapeutic tool for treatment of diseases. However, misuse can lead to an adverse drug event (ADE) in susceptible individuals such as those that are severely obese. This study aimed to describe the frequency of ADEs, the associations of ADEs with anatomical therapeutic chemical classes and their respective frequency, estimate the prevalence of ADEs, and analyse factors associated with ADE in adults with severe obesity. Cross-sectional analysis of baseline data from a randomized clinical trial in the central-western region of Brazil. A total of 150 individuals aged 18–65 years with a Body Mass Index of 35 kg/m2 were included. The outcome variable was the presence of ADE and the explanatory variables were socio-demographic factors, lifestyle, health, and medication use. ADEs were associated with use of drugs for the digestive tract and metabolism (p < 0.001) and the cardiovascular system (p < 0.001). The prevalence of ADEs was 32.67% (n = 49) and associated with the age range 40 to 49 years (p = 0.033), diabetes (p = 0.004), multimorbidities ≥ 4 (p = 0.009), self-medication (0.031), and presence of potential drug interactions (0.017). The prevalence of ADEs was high and was associated with drugs commonly used in treatment of obesity-related morbidities and self-medication. The introduction of a pharmacist to multi-professional teams can improve medication safety for severely obese patients.

Dihydropyranocoumarins Exerted Anti-Obesity Activity In Vivo and its Activity Was Enhanced by Nanoparticulation with Polylactic-Co-Glycolic Acid

Dihydropyranocoumarins (DPCs) were isolated from Peucedanum japonicum Thunb as anti-obesity compounds in 3T3-L1 adipocytes assay; however, it is uncertain whether DPC exerts anti-obesity activity in vivo. Therefore, this study evaluated the oral intake of pure DPCs in mice fed a high-fat diet, and also attempted to enhance its activity by nanoparticulation. Increases in body weight gain and fat accumulation in white adipose tissues were significantly suppressed by the dietary intake of DPCs (1.943 mg/mouse/day). DPCs intake also significantly decreased the mean size of adipocytes and upregulated mRNA levels of thermogenesis-related genes. Nanoparticulation of DPCs with polylactic-co-glycolic acid (PLGA) dramatically increased its activity almost 100-fold over that of a non-nanoparticulated form. Thus, our findings clearly demonstrated the anti-obesity activity of DPCs in vivo and suggested that PLGA nanoparticle encapsulation was useful to enhance the anti-obesity activity of DPCs with the aim to develop natural and safe anti-obesity agents.

Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study

Introduction

Vitamin D (vit D) deficiency has defined as a health problem worldwide. World Health Organization (WHO) has declared that obesity is an epidemic of the 21^st century. Previous studies have shown that obesity may increase the risk of Vit D deficiency. Furthermore, other studies have demonstrated that vit D insufficiency was accompanied with higher risk of type 2 diabetes, cardiovascular diseases, hypertension, and obesity. The aim of this study was to survey the effect of vit D supplementation on weight loss among overweight and obese women aged 20-40 years in Isfahan.

Methods

This double-blind clinical trial was done on 50 overweight and obese women who were divided into two groups, in which one group received vit D supplements and the other group received placebo. Intervention group received vit D with dozes 50,000 IU/w for 6 weeks. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), fasting blood sugar (FBS), insulin (ins), homeostasis model assessment of ins resistance (IR), C-reactive protein (CRP), height, weight (WT), waist circumference (WC), hip circumference (HC), and blood pressure (BP) were measured before and after intervention.

Results

After using vit D supplementation for 6 weeks, WT, WC, and body mass index (BMI) were decreased significantly and serum vit D increased significantly compared to control group (P < 0.001). Other factors including TC, TG, LDL-c, HDL-c, FBS, CRP, ins, IR, and waist to hip ratio (WHR) did not change significantly (P > 0.05).

Conclusions

After 6 weeks of intervention, the means of WT, BMI, WC, and HC decreased significantly. Previous studies have shown that vit D deficiency was more prevalence in obese people and there was an inverse association among vit D with BMI and WC. The relationship between vit D and lipid profiles such as glycemic indexes, anthropometric indexes, CRP, and BP is not clear and needs more study in the future.

Role of adipocytes in hypertension

Although it has known for some time that obesity is associated with salt sensitivity and hypertension, recent data suggests that the adipocyte may actually be the proximate cause of this physiological changes. In the following review, the data demonstrating this association as well as the potentially operative pathophysiological mechanisms are reviewed and discussed.

FNDC5 is produced in the stomach and associated to body composition

The fibronectin type III domain-containing protein 5 (FNDC5) discovered in 2002 has recently gained attention due to its potential role in protecting against obesity. In rat, no data exist regarding FNDC5 production and regulation in the stomach. The aim of the present work was to determine the expression of FNDC5 in the rat stomach and its potential regulation by body composition. The present data shows FNDC5 gene expression in the gastric mucosa. Immunohistochemical studies found FNDC5 immunopositivity in chief cells of gastric tissue. By the use of three different antibodies FNDC5 was found expressed in gastric mucosa and secreted by the stomach. The rate of gastric FNDC5 secretion parallels the circulating levels of FNDC5. The body fat mass increase after intervention with high fat diet coincided with a decrease in the secretion of FNDC5 from the stomach and a diminution in the FNDC5 circulating levels. In summary, the present data shows, for the first time, the expression of FNDC5 in the stomach of rats and its regulation by body composition, suggesting a potential role of gastric FNDC5 in energy homeostasis.

Liraglutide: a review of its use in the management of obesity

Globally, obesity has reached epidemic proportions and poses an ever increasing burden from a societal and healthpayer perspective. Although lifestyle interventions are fundamental in its management, in the real world setting most obese or overweight adults require adjunctive pharmacotherapy to achieve clinically relevant reductions in bodyweight (i.e. a ≥5 % reduction). Subcutaneous liraglutide (Saxenda(®)) 3 mg once daily is indicated as an adjunct to a reduced-calorie diet and increased physical activity for chronic bodyweight management in adults with an initial body mass index (BMI) of ≥30 kg/m(2) (obese) or a BMI of ≥27 kg/m(2) (overweight) and at least one bodyweight-related comorbidity [e.g. hypertension, dyslipidaemia, type 2 diabetes mellitus or obstructive sleep apnoea (OSA)]. In phase III trials (32 or 56 weeks' duration) in these populations, subcutaneous liraglutide was associated with clinically relevant reductions in fasting bodyweight and was generally well tolerated. Liraglutide was significantly more effective than placebo in terms of reductions in fasting bodyweight and waist circumference, and improvements in some biomarkers of cardiovascular risk. Improvements in bodyweight were maintained after up 2 years of liraglutide therapy. In nondiabetic adults with moderate to severe OSA, liraglutide improved apnoea-hypopnoea index scores at 32 weeks, which was largely driven by significant reductions in bodyweight. In the absence of head-to-head trials, the relative position of individual anti-obesity drugs remains to be fully determined. In the meantime, liraglutide is an emerging option, as an adjunct to a reduced-calorie diet and increased physical activity, for chronic bodyweight management in obese adults and overweight adults with at least one bodyweight-related comorbidity.

Peripheral signals mediate the beneficial effects of gastric surgery in obesity

Obesity is nowadays a public health problem both in the industrialized world and developing countries. The different treatments to fight against obesity are not very successful with the exception of gastric surgery. The mechanism behind the achievement of this procedure remains unclear although the modifications in the pattern of gastrointestinal hormones production appear to be responsible for the beneficial effect. The gastrointestinal tract has emerged in the last time as an endocrine organ in charge of response to the different stimulus related to nutritional status by the modulation of more than 30 signals acting at central level to modulate food intake and body weight. The production of some of these gastric derived signals has been proved to be altered in obesity (ghrelin, CCK, and GLP-1). In fact, bariatric surgery modifies the production of both gastrointestinal and adipose tissue peripheral signals beyond the gut microbiota composition. Through this paper the main peripheral signals altered in obesity will be reviewed together with their modifications after bariatric surgery.