Pharmacological treatment of the overweight patient

Phentermine in the Modern Era of Obesity Pharmacotherapy: Does It Still Have a Role in Treatment?

PURPOSE OF REVIEW

This review provides an overview of the history, mechanism of action, and expected treatment effects of the anti-obesity medication (AOM), phentermine. It also includes a summary of recent research and practical guidance for prescribing clinicians.

RECENT FINDINGS

Recent research on phentermine is sparse and consists primarily of observational studies with methodologic limitations. These studies suggest that phentermine use is associated with clinically significant weight loss in adults and that the medication is generally well tolerated. Large-scale observational studies evaluating phentermine's safety have not identified an increased risk of cardiovascular events or elevations in blood pressure. There is no data to support the notion that phentermine is addictive. Although it remains the most commonly prescribed AOM in the USA, phentermine has little rigorous research to support its efficacy and safety in long-term treatment, which creates a dilemma with guideline-recommended chronic use of AOMs. While we await forthcoming conclusive data on this front, clinicians may consider using phentermine long-term in selected patients, if such prescribing is consistent with local regulatory statutes.

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

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

Encapsulated Peptides and Proteins with an Effect on Satiety

The world scenario has undergone a nutritional transition in which some countries have left the reality of malnutrition and now face an epidemic of excess body weight. Researchers have been looking for strategies to reverse this situation. Peptides and proteins stand out as promising molecules with anti-obesity action. However, oral administration and passage through the gastrointestinal tract face numerous physiological barriers that impair their bioactive function. Encapsulation aims to protect the active substance and modify the action, one possibility of potentiating anti-obesity activity. Research with encapsulated peptides and proteins has demonstrated improved stability, delivery, controlled release, and increased bioactivity. However, it is necessary to explore how proteins and peptides affect weight loss and satiety, can impact the nutritional status of obesity, and how encapsulation can enhance the bioactive effects of these molecules. This integrative review aimed to discuss how the encapsulation of protein molecules impacts the nutritional status of obesity. From the studies selected following pre-established criteria, it was possible to infer that the encapsulation of proteins and peptides can contribute to greater efficiency in reducing weight gain, changes in adipose tissue function, and lower hormone levels that modulate appetite and body weight in animals with obesity.

Biomaterial-Based Therapeutic Strategies for Obesity and Its Comorbidities

Obesity is a global public health issue that results in many health complications or comorbidities, including type 2 diabetes mellitus, cardiovascular disease, and fatty liver. Pharmacotherapy alone or combined with either lifestyle alteration or surgery represents the main modality to combat obesity and its complications. However, most anti-obesity drugs are limited by their bioavailability, target specificity, and potential toxic effects. Only a handful of drugs, including orlistat, liraglutide, and semaglutide, are currently approved for clinical obesity treatment. Thus, there is an urgent need for alternative treatment strategies. Based on the new revelation of the pathogenesis of obesity and the efforts toward the multi-disciplinary integration of materials, chemistry, biotechnology, and pharmacy, some emerging obesity treatment strategies are gradually entering the field of preclinical and clinical research. Herein, by analyzing the current situation and challenges of various new obesity treatment strategies such as small-molecule drugs, natural drugs, and biotechnology drugs, the advanced functions and prospects of biomaterials in obesity-targeted delivery, as well as their biological activities and applications in obesity treatment, are systematically summarized. Finally, based on the systematic analysis of biomaterial-based obesity therapeutic strategies, the future prospects and challenges in this field are proposed.

Metformin Intervention—A Panacea for Cancer Treatment?

The molecular mechanism of action and the individual influence of various metabolic pathways related to metformin intervention are under current investigation. The available data suggest that metformin provides many advantages, exhibiting anti-inflammatory, anti-cancer, hepatoprotective, cardioprotective, otoprotective, radioprotective, and radio-sensitizing properties depending on cellular context. This literature review was undertaken to provide novel evidence concerning metformin intervention, with a particular emphasis on cancer treatment and prevention. Undoubtedly, the pleiotropic actions associated with metformin include inhibiting inflammatory processes, increasing antioxidant capacity, and improving glycemic and lipid metabolism. Consequently, these characteristics make metformin an attractive medicament to translate to human trials, the promising results of which were also summarized in this review.

What are the mechanisms of action of anti-inflammatory agents in adipose tissue?: A protocol for systematic review and meta-analysis

BACKGROUND

Obesity is a disease characterized by the abnormal accumulation of adipose tissue in the body, triggering a chronic subclinical state of inflammation. Bioactive compounds, given their anti-inflammatory properties, are a safe and promising alternative in controlling the inflammatory condition of obesity. This study describes a systematic review protocol aiming to analyze the anti-inflammatory molecules mechanisms and compounds action on adipocytes.

METHODS

Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) will outline the protocol and PRISMA to the systematic review. The databases used for research will be PubMed, Science Direct, Scopus, Web of Science, BVS, and EMBASE. Experimental studies performed on rats and mice with a control group that describes treatment with anti-inflammatory agents (drugs, nutraceuticals, bio active compounds, among others) at any frequency, time, and dose will be included. Three independent reviewers will select studies and extract data. The evaluation of the methodological quality of each research will be performed using the SYRCLE tool. If at least 2 studies show clinical and/or methodological and/or statistical homogeneity, a meta-analysis will be performed, using the RevMan Analyzes statistical package in Review Manager v.5.3.

RESULTS

In this study, we hope to find a considerable number of articles presenting mechanisms involved in the action of anti-inflammatory molecules and compounds on adipocytes.

CONCLUSION

The systematic review produced from this protocol will present evidence on the mechanisms involved in the action of anti-inflammatory molecules and compounds in adipocytes. It will also contribute to developing new research and new insights about anti-inflammatory therapies with a future application view.

RECORD OF SYSTEMATIC REVIEW

This review was registered with the International Register of Prospective Systematic Reviews on May 18, 2020 (registration: CRD42020182897). Available at: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020182897.

Counterfeit formulations: analytical perspective on anorectics

Purpose

This paper examines the scope of anorectics in counterfeit weight-reducing formulations and provides insight into the present state of research in determining such adulterants. Analytical techniques utilised in profiling adulterants found in slimming products, including limitations and mitigation steps of these conventional methods are also discussed. The current legal status of the anorectics and analogues routinely encountered in non-prescription slimming formulations is also explored.

Methods

All reviewed literature was extracted from Scopus, Web of Science, PubMed, and Google Scholar databases using relevant search terms, such as, ‘counterfeit drugs’, ‘weight loss drugs’, ‘weight-reducing drugs’, ‘slimming drugs’, ‘anorectic agents’, and ‘counterfeit anorexics’. Legislation related to anorectics was obtained from the portals of various government and international agencies.

Results

Anorectics frequently profiled in counterfeit slimming formulations are mostly amphetamine derivatives or its analogues. Five routinely reported pharmacological classes of adulterants, namely anxiolytics, diuretics, antidepressants, laxatives, and stimulants, are mainly utilised as coadjuvants in fake weigh-reducing formulations to increase bioavailability or to minimise anticipated side effects. Liquid and gas chromatography coupled with mass spectrometric detectors are predominantly used techniques for anorectic analysis due to the possibility of obtaining detailed information of adulterants. However, interference from the complex sample matrices of these fake products limits the accuracy of these methods and requires robust sample preparation methods for enhanced sensitivity and selectivity. The most common anorectics found in counterfeit slimming medicines are either completely banned or available by prescription only, in many countries.

Conclusions

Slimming formulations doped with anorectic cocktails to boost their weight-reducing efficacy are not uncommon. Liquid chromatography combined with mass spectrometry remains the gold standard for counterfeit drug analysis, and requires improved preconcentration methods for rapid and quantitative identification of specific chemical constituents. Extensive method development and validation, targeted at refining existing techniques while developing new ones, is expected to improve the analytical profiling of counterfeit anorectics significantly.

Growth differentiation factor 15 as a potential therapeutic for treating obesity

BACKGROUND

Obesity is rapidly becoming one of the world's most critical health care concerns. Comorbidities accompanying excess weight include cardiovascular disease, diabetes, and certain cancers. These comorbidities result in greater hospitalization and other health care-related costs. Economic impacts are likely to be felt more acutely in developing countries, where obesity rates continue to rise and health care resources are already insufficient. Some of the more effective treatments are invasive and expensive surgeries, which some economies in the world cannot afford to offer to a broad population. Pharmacological therapies are needed to supplement treatment options for patients who cannot, or will not, undergo surgical treatment. However, the few drug therapies currently available have either limited efficacy or safety concerns. A possible exception has been glucagon-like peptide-1 analogs, although these have shown a number of adverse events. New drug therapies that are safe and produce robust weight loss are needed.

SCOPE OF REVIEW

Herein, we review the role of growth differentiation factor 15 (GDF15) in feeding behavior and obesity, summarize some of the new and exciting biological discoveries around signaling pathways and tissue sites of action, and highlight initial efforts to develop GDF15-based therapies suitable for inducing weight loss in humans.

MAJOR CONCLUSIONS

Within the last several years, great strides have been made in understanding the biology of GDF15. Recent developments include identification of an endogenous receptor, biological localization of the receptor system, impact on energy homeostasis, and identification of molecules suitable for administration to humans as anti-obesity treatments. New and exciting research on GDF15 suggests that it holds promise as a novel obesity treatment as new molecules progress toward clinical development.

Inhibition of glutathione and s-allyl glutathione on pancreatic lipase: Analysis through in vitro kinetics, fluorescence spectroscopy and in silico docking

Inhibition of pancreatic lipase (PL) is considered one of the important therapeutic interventions against obesity. In the present study, the inhibition of porcine (mammalian) PL (PPL) by two tripeptides glutathione (GSH) and s-allyl glutathione (SAG) was studied. In vitro kinetic analysis was done to determine the inhibition of GSH and SAG against PPL. The binding of GSH and SAG with PPL was elucidated by fluorescence spectroscopy analysis. Docking and molecular dynamics (MD) simulation analysis was carried out to understand the intermolecular interaction between both GSH and SAG with PPL as well as human PL (HPL). Both GSH and SAG inhibited PPL in mixed non-competitive manner. The IC₅₀ value for GSH and SAG against PPL was found to be 2.97 and 6.4 mM, respectively. Both GSH and SAG quenched the intrinsic fluorescence of PPL through static quenching that is through forming complex with the PPL. SAG and GSH interacted with amino acids involved in catalysis of both PPL and HPL. MD simulation showed interactions of SAG and GSH with both PPL and HPL were stable. These results would lead to the further studies and application of GSH and SAG against obesity through inhibition of PL.

Antiobesity effects of seedlac and shellac in rats fed with a high-fat diet

Background and purpose

Obesity is a global health problem and also a well-known risk for many diseases. Although some synthetic drugs have been marketed for the treatment of obesity, natural remedies may be considered as safe and cost-effective alternatives. Lac (Kerria lacca Kerr) is a product from animal origin and is sold as seedlac or shellac. This drug is very famous among Unani practitioners for its antiobesity effects. The aim of the present study was to evaluate the antiobesity potential of lac in rats.

Experimental approach

The effect of lac on rats fed with a high-fat diet (HFD) was investigated through determination of the changes in body weight, and serum levels of leptin. In addition, the effect of lac on total cholesterol, triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) was studied. Male Wistar rats (170-220 g) were divided into eight groups; a control group with normal diet, the HFD group received a HFD, and the experimental groups received the HFD containing 0.1, 0.2, and 0.4% (w/w) of seedlac or 0.1, 0.2, and 0.4% (w/w) of shellac for 12 weeks. The body weight of each rat was measured once a week. At the end of the experiment, animals were sacrificed and serum concentrations of cholesterol, TG, low-density lipoprotein-cholesterol, high-density lipoprotein-cholesterol, and leptin were determined.

Results

The study showed that seedlac and shellac significantly prevented increasing body weight and the levels of serum leptin were decreased in treated groups compared with HFD group. Also, shellac decreased TG level and both shellac and seedlac exerted a significant increase in HDL-C concentration.

Conclusion and implications

Lac had weight-reducing properties and could be a promising alternative for controlling obesity.

Pharmacogenetics of amfepramone in healthy Mexican subjects reveals potential markers for tailoring pharmacotherapy of obesity: results of a randomised trial

Amfepramone (AFP) is an appetite-suppressant drug used in the treatment of obesity. Nonetheless, studies on interindividual pharmacokinetic variability and its association with genetic variants are limited. We employed a pharmacokinetic and pharmacogenetic approach to determine possible metabolic phenotypes of AFP and identify genetic markers that could affect the pharmacokinetic variability in a Mexican population. A controlled, randomized, crossover, single-blind, two-treatment, two-period, and two sequence clinical study of AFP (a single 75 mg dose) was conducted in 36 healthy Mexican volunteers who fulfilled the study requirements. Amfepramone plasma levels were measured using high-performance liquid chromatography mass spectrometry. Genotyping was performed using real-time PCR with TaqMan probes. Four AFP metabolizer phenotypes were found in our population: slow, normal, intermediate, and fast. Additionally, two gene polymorphisms, ABCB1-rs1045642 and CYP3A4-rs2242480, had a significant effect on AFP pharmacokinetics (P < 0.05) and were the predictor factors in a log-linear regression model. The ABCB1 and CYP3A4 gene polymorphisms were associated with a fast metabolizer phenotype. These results suggest that metabolism of AFP in the Mexican population is variable. In addition, the genetic variants ABCB1-rs1045642 and CYP3A4-rs2242480 may partially explain the AFP pharmacokinetic variability.

Pharmacotherapy of Obesity: Limits and Perspectives

Obesity is a severe worldwide epidemic. Obesity comorbidities, such as type 2 diabetes mellitus, hypertension, and atherosclerosis, are costly for patients and governments. The treatment of obesity involves several facets, including lifestyle changes, bariatric surgery, and pharmacotherapy. As changes in lifestyle require considerable patient commitment that is sometimes unachievable, and surgery is expensive and invasive, pharmacotherapy is the primary option for most patients. This review describes the pharmacotherapy currently available in the USA, Europe, and Brazil, focusing on its limitations. We then analyze the results from clinical trials of new drug candidates. Most drugs cause weight loss of < 4 kg compared with controls, and severe adverse effects have caused a number of drugs to be withdrawn from the market in several countries. Drugs under development have not shown more significant weight loss or reduced adverse effects. We conclude that a significant portion of obese patients have few treatment options because of the adverse effects and minimal weight loss associated with current pharmacotherapy. However, drugs currently under development appear unable to change this scenario in the near future. Thus, it is essential that new compounds are developed and new molecular targets studied so obesity can be efficiently treated in all patients in the future.

A Randomized, Double-Blind, Placebo-Controlled Study of Gelesis100: A Novel Nonsystemic Oral Hydrogel for Weight Loss

OBJECTIVE

This study aims to assess the efficacy and safety of Gelesis100, a novel, nonsystemic, superabsorbent hydrogel to treat overweight or obesity.

METHODS

The Gelesis Loss Of Weight (GLOW) study was a 24-week, multicenter, randomized, double-blind, placebo-controlled study in patients with BMI ≥  27 and ≤ 40 kg/m2 and fasting plasma glucose ≥ 90 and ≤ 145 mg/dL. The co-primary end points were placebo-adjusted weight loss (superiority and 3% margin super-superiority) and at least 35% of patients in the Gelesis100 group achieving ≥ 5% weight loss.

RESULTS

Gelesis100 treatment caused greater weight loss over placebo (6.4% vs. 4.4%, P = 0.0007), achieving 2.1% superiority but not 3% super-superiority. Importantly, 59% of Gelesis100-treated patients achieved weight loss of ≥ 5%, and 27% achieved ≥ 10% versus 42% and 15% in the placebo group, respectively. Gelesis100-treated patients had twice the odds of achieving ≥ 5% and ≥ 10% weight loss versus placebo (adjusted OR: 2.0, P = 0.0008; OR: 2.1, P = 0.0107, respectively), with 5% responders having a mean weight loss of 10.2%. Patients with prediabetes or drug-naive type 2 diabetes had six times the odds of achieving ≥ 10% weight loss. Gelesis100 treatment had no apparent increased safety risks.

CONCLUSIONS

Gelesis100 is a promising new nonsystemic therapy for overweight and obesity with a highly desirable safety and tolerability profile.

Use of Metformin for Weight Management in Children and Adolescents With Obesity in the Clinical Setting

Use of metformin for weight loss for children in a clinical setting has not been well described; therefore, we aimed to identify characteristics of obese patients prescribed metformin in a clinical setting and evaluate changes in anthropometric measures. Records of obese patients aged 10 to 18 years without diabetes attending an academic endocrinology practice from 2009 to 2013 were reviewed. Analyses assessed changes in anthropometric measures (weight, body mass index [BMI], and BMI z-score) over 12 months between those prescribed metformin (n = 49) and those not prescribed metformin (n = 142). Outcomes were standardized before using multivariable linear regression models. Patients prescribed metformin were significantly older, more often female, and had larger baseline anthropometric measures (all P < .05). In the models, subjects prescribed metformin had significantly less gain in standardized weight, BMI, and BMI z-score over 6 and 12 months (all P < .05). Metformin may be a useful weight management aid in children in a clinical setting.

Combination of Garcinia cambogia Extract and Pear Pomace Extract Additively Suppresses Adipogenesis and Enhances Lipolysis in 3T3-L1 Cells

Background:

Inhibition of adipogenesis has been a therapeutic target for reducing obesity and obesity-related disorders such as diabetes, hypertension, atherosclerosis, and cancer. For decades, anti-adipogenic potential of many herbal extracts has been investigated. One example is Garcinia cambogia extract (GE) containing (-)-hydroxycitric acid as an active ingredient. GE is currently marketed as a weight loss supplement, used alone or with other ingredients. Pear pomace extract (PE), another natural product, has been also shown to have anti-adipogenic activity in a recent report.

Objective:

It was tested if the mixture of PE and GE (MIX) would produce more effective anti-adipogenic activity than PE or GE alone.

Materials and Methods:

Differentiation of 3T3-L1 preadipocyte was induced by adding insulin, dexamethasone, and isobutylmethylxanthine and lipid accumulation was measured by Oil Red O staining. Cellular markers for adipogenesis and lipolysis such as CCAAT/enhancer binding protein (C/EBP-α), peroxisome proliferator-activated receptor gamma (PPAR-γ), fatty acid synthase (FAS), and hormone-sensitive lipase (HSL) was measured using immunocytochemistry.

Results:

MIX, compared to PE or GE alone, showed greater inhibition of lipid accumulation. Furthermore, MIX reduced the expression of adipogenesis-related factors C/EBP-α, PPAR-γ, and FAS more than PE or GE alone did. In contrast, the expression of HSL the enzyme required for lipolysis was further enhanced in MIX-treated adipocytes compared to the PE or GE alone treated groups.

Conclusions:

Anti-adipogenic effect of PE and GE appears synergistic, and the MIX may be a useful therapeutic combination for the treatment of obesity and obesity-related diseases.

SUMMARY

PE and GE efficiently inhibited adipocyte differentiation by suppressing the expression of adipogenic transcription factor CEBP-α and PPAR-γ.

PE and GE significantly decreased the expression of adipogenic enzyme FAS.

PE and GE increased the expression of lipid degrading enzyme HSL.

Mixture of PE and GE exhibited additive or moderately synergistic effect on adipocyte differentiation and lipid accumulation.

Abbreviations used: CEBP-a: CCAT/enhancer binding protein alpha, CI: Combination Index, FAS: Fatty acid synthase, GE: Garcinia cambogia extract, HSL: Hormone sensitive lipase, PE: Pear pomace extract, PPAR-γ: Peroxisome proliferator-activated receptor gamma.

The Science of Obesity Management: An Endocrine Society Scientific Statement

The prevalence of obesity, measured by body mass index, has risen to unacceptable levels in both men and women in the United States and worldwide with resultant hazardous health implications. Genetic, environmental, and behavioral factors influence the development of obesity, and both the general public and health professionals stigmatize those who suffer from the disease. Obesity is associated with and contributes to a shortened life span, type 2 diabetes mellitus, cardiovascular disease, some cancers, kidney disease, obstructive sleep apnea, gout, osteoarthritis, and hepatobiliary disease, among others. Weight loss reduces all of these diseases in a dose-related manner-the more weight lost, the better the outcome. The phenotype of "medically healthy obesity" appears to be a transient state that progresses over time to an unhealthy phenotype, especially in children and adolescents. Weight loss is best achieved by reducing energy intake and increasing energy expenditure. Programs that are effective for weight loss include peer-reviewed and approved lifestyle modification programs, diets, commercial weight-loss programs, exercise programs, medications, and surgery. Over-the-counter herbal preparations that some patients use to treat obesity have limited, if any, data documenting their efficacy or safety, and there are few regulatory requirements. Weight regain is expected in all patients, especially when treatment is discontinued. When making treatment decisions, clinicians should consider body fat distribution and individual health risks in addition to body mass index.

Molecular and functional genetics of the proopiomelanocortin gene, food intake regulation and obesity

A specter is haunting the world, the specter of obesity. During the last decade, this pandemia has skyrocketed threatening children, adolescents and lower income families worldwide. Although driven by an increase in the consumption of ultraprocessed edibles of poor nutritional value, the obesogenic changes in contemporary human lifestyle affect people differently, revealing that some individuals are more prone to develop increased adiposity. During the last years, we performed a variety of genetic, evolutionary, biochemical and behavioral experiments that allowed us to understand how a group of neurons present in the arcuate nucleus of the hypothalamus regulate the expression of the proopiomelanocortin (Pomc) gene and induce satiety. We disentangled the neuronal transcriptional code of Pomc by identifying the cis-acting regulatory elements and primary transcription factors controlling hypothalamic Pomc expression and determined their functional importance in the regulation of food intake and adiposity. Altogether, our studies reviewed here shed light on the power and limitations of the mammalian central satiety pathways and may contribute to the development of individual and collective strategies to reduce the debilitating effects of the self-induced obesity pandemia.

Further delineation between typical and atypical dopamine uptake inhibitors: effects on food-maintained behavior and food consumption

The present studies compared the acute effects of benztropine analogs (4-Cl-BZT, JHW 007, AHN 1-055), which are atypical dopamine uptake inhibitors, with those of the standard dopamine uptake inhibitors GBR 12909 and cocaine, on the reinforcing efficacy of food and food intake in male Sprague-Dawley rats. Repeated drug effects of JHW 007 on food intake were also determined. The number of ratios completed under a progressive-ratio schedule of food delivery was used as an index of reinforcing efficacy. Food intake was determined by measuring powdered laboratory-chow consumption during daily 40 min food-availability time periods. Under the progressive-ratio schedule, cocaine and GBR 12909 dose-dependently increased the number of ratios completed. JHW 007 decreased ratios completed, whereas neither 4-Cl-BZT nor AHN 1-055 increased ratios completed with a magnitude that approximated any of the increases produced by cocaine or GBR 12909. Acute administration of each drug dose-dependently decreased food intake; however, the benztropine analogs were more potent than cocaine and GBR 12909. A reduction in food intake emerged after repeated administration of a low dose of JHW 007. Future studies that compare JHW 007 with standard anorectic drugs (e.g. phentermine) and continue investigation of the repeated drug effects under similar experimental procedures are clearly warranted.

The effect of caffeine and albuterol on body composition and metabolic rate

OBJECTIVE

Caffeine and ephedrine was an effective combination therapy for weight loss until ephedrine was removed from the market due to safety concerns. This study investigated the combination of caffeine and albuterol as a possibly safer alternative to ephedrine.

METHODS

In a series of experiments using cultured adipocytes, rat models, and humans, the effects of caffeine and albuterol on lipolysis, metabolic rate, food intake, and body composition were evaluated.

RESULTS

Both caffeine and albuterol enhanced lipolysis in cultured adipocytes. Acute treatment of humans with caffeine and/or albuterol increased resting metabolic rate. Longer-term studies of rats revealed a trend for increased metabolic rate with albuterol treatment. There was increased lean mass gain concurrent with decreased fat mass gain with caffeine/albuterol treatment that was greater than albuterol treatment alone.

CONCLUSIONS

In rats, albuterol with caffeine produced significantly greater increases in lean body mass and reductions in fat mass without changes in food intake after 4-8 weeks of treatment. Since caffeine and albuterol are approved for the treatment of asthma in children and adolescents at the doses tested and change body composition without changing food intake, this combination may deserve further exploration for use in treating pediatric obesity.

The Use of Green Leaf Membranes to Promote Appetite Control, Suppress Hedonic Hunger and Loose Body Weight

On-going research aims at answering the question, which satiety signal is the most potent or which combination of satiety signals is the most potent to stop eating. There is also an aim at finding certain food items or food additives that could be used to specifically reduce food intake therapeutically. Therapeutic attempts to normalize body weight and glycaemia with single agents alone have generally been disappointing. The success of bariatric surgery illustrates the rationale of using several hormones to treat obesity and type-2-diabetes. We have found that certain components from green leaves, the thylakoids, when given orally have a similar rationale in inducing the release of several gut hormones at the same time. In this way satiety is promoted and hunger suppressed, leading to loss of body weight and body fat. The mechanism is a reduced rate of intestinal lipid hydrolysis, allowing the lipolytic products to reach the distal intestine and release satiety hormones. The thylakoids also regulate glucose uptake in the intestine and influences microbiota composition in the intestine in a prebiotic direction. Using thylakoids is a novel strategy for treatment and prevention of obesity.

Chinese herbal medicine for obesity: a randomized, double-blinded, multicenter, prospective trial

Obesity is a serious medical problem worldwide. As a holistic therapy, traditional Chinese medicine (TCM) may have a potential in obesity management. In this controlled trial, we evaluated the safety and effectiveness of xin-ju-xiao-gao-fang (XJXGF), a TCM herbal formulation, in 140 obese subjects over a 24-week period. The XJXGF formula mainly consists of rhubarb, coptis, semen cassia, and citrus aurantium. Subjects with body mass index (BMI) 28-40 kg/m(2) were recruited at 5 centers in China. We assessed the changes in subjects' body weight, its related parameters, and the reduction of insulin resistance (IR) after administration of XJXGF formula or low-dose XJXGF (10% of the XJXGF formula, as control). After 24-week treatment, among participants in the XJXGF formula group and low-dose XJXGF group, the mean ± SE changes in the body weight were -3.58 ± 0.48 and -1.91 ± 0.38 kg, respectively (p < 0.01). The changes in the IR-index of two groups were -2.65 ± 1.04 and -1.58 ± 1.3, respectively (p < 0 .05). There were no serious adverse events reported during the 24-week trial. Participants reported 7 minor adverse events, 4 in the XJXGF formula group and 3 in the low-dose XJXGF group (p = 0.578). Future studies are needed to investigate the clinical utility of this TCM formulation in the treatment of obese subjects.

Current trends and future prospects of lipstatin: a lipase inhibitor and pro-drug for obesity

A review of the implications and causes of obesity, the status of antiobesity drugs, the mechanism of inhibition of pancreatic lipases, the biosynthesis of lipstatin and the present status of lipstatin production.

Pharmacotherapy for obesity

Obesity is an important risk factor for metabolic disease and various cancers. Treatments of obesity include lifestyle intervention, pharmacotherapy, and bariatric surgery. If weight loss with lifestyle intervention is only modest, pharmacotherapy might be needed. Pharmacotherapy agents can be grouped by treatment period as short term or long term use agent. Several sympathomimetic drugs such as benzphetamine, diethylpropion, phendimetrazine and phentermine, are approved for short term treatment due to their safety issues. For long term treatment, orlistat, lorcaserin, and combination of phentermine/topiramate are approved by U.S. Food and Drug Administration (FDA). Orlistat partially blocks intestinal digestion of fat, therefore producing weight loss. Lorcaserin is a serotonin 2C receptor agonist. The combination of phentermine/topiramate produces a mean weight loss of 8-10 kg. Side effects of each drug are quite different. For obesity patient, side effects are important factor when choosing drugs. The goal of this article is to review currently available anti-obesity drugs.

Medical treatment of obesity: the past, the present and the future

Medications for the treatment of obesity began to appear in the late 19th and early 20th century. Amphetamine-addiction led to the search for similar drugs without addictive properties. Four sympathomimetic drugs currently approved in the US arose from this search, but may not be approved elsewhere. When noradrenergic drugs were combined with serotonergic drugs, additional weight loss was induced. At present there are three drugs (orlistat, phentermine/topiramate and lorcaserin) approved for long-term use and four sympathomimetic drugs approved by the US FDA for short-term treatment of obesity. Leptin produced in fat cells and glucagon-like peptide-1, a gastrointestinal hormone, provide a new molecular basis for treatment of obesity. New classes of agents acting on the melanocortin system in the brain or mimicking GLP-1 have been tried with variable success. Combination therapy can substantially increase weight loss; a promising approach for the future.

Liraglutide in the treatment of obesity

INTRODUCTION

Obesity is a global epidemic with important healthcare and financial implications. Most current antiobesity pharmacological therapies are unsatisfactory due to undesirable side effects. Many drugs have been withdrawn due to safety concerns. Maintaining weight loss remains the Achilles' heel of antiobesity therapy.

AREAS COVERED

This is an overview of the use of liraglutide for obesity treatment. Clinical efficacy on weight, cardiovascular parameters, as well as safety and tolerability issues are discussed.

EXPERT OPINION

Liraglutide is a glucagon-like peptide 1 (GLP-1) receptor agonist, which has a protracted pharmacokinetic profile compared to native GLP-1 while maintaining its biological activity. It induces weight loss by reducing appetite and energy intake. It stimulates insulin release and decreases glucagon secretion in response to hyperglycaemia. Treatment with liraglutide, in addition with diet and exercise, induces sustained mean weight loss of 7.6 kg at 2 years (weight loss induced by orlistat = 5.7 kg, phentermine/topiramate controlled release 15/92 = 10.9 kg). It reduces blood pressure and improves glycaemic control, which has clinically relevant significance on reducing obesity-related morbidity and mortality. Liraglutide is reasonably well tolerated with gastrointestinal side effects being most commonly encountered. Novo Nordisk filed for regulatory approval of liraglutide 3.0 mg for obesity treatment in December 2013.

Drug treatment of obesity in the cardiovascular patient

PURPOSE OF REVIEW

The incidence of obesity and its associated comorbidities have significantly increased over the years with adverse health and financial consequences for society. Lifestyle changes are essential for the prevention and treatment of obesity but their benefit appears limited as inadequate and nonsustained weight loss results have been reported. Pharmacotherapy is frequently advocated as part of a weight loss strategy. In this review, we will discuss the antiobesity drugs with Food and Drug Administration approval and their cardiovascular implications.

RECENT FINDINGS

Orlistat (Xenical) remains the single monotherapy that has approval in Europe. Topiramate (Topamax) and phentermine have long been approved in the United States, whereas lorcaserin and the extended release combination of phentermine with topiramate have recently gained approval. The development of single peptides targeting gut hormones or other host signals related to obesity may represent promising therapeutic options.

SUMMARY

Despite the recent failures of a number of antiobesity drugs, the pharmacotherapy of obesity is progressing rapidly. Treating the obese cardiovascular patient has proven challenging. Efficacy, safety and the sustainability of weight loss are key areas of focus in drug development strategies.

Update on obesity pharmacotherapy

There are two groups of approved drugs that can be used to manage weight in patients with obesity: medications approved for obesity per se and medications that affect body weight for obese patients who have complications from their obesity and are receiving these medications for chronic disease management. For obesity per se, treatment is with one of the three drugs currently approved for long-term treatment of obesity or one of a few others that can be used for short-term treatment. Among these, orlistat partially blocks intestinal digestion of fat and produces weight loss of 5-8 kg but major limitations are associated gastrointestinal symptoms; lorcaserin, a serotonin-2C agonist with few side effects, produces a mean weight loss of 4-7 kg; and the combination of phentermine and topiramate (extended release) produces a mean weight loss of 8-10 kg, but should only be used after verifying a woman is not pregnant. Failure to lose more than 3% of body weight within 3 months with any of these agents should lead to reevaluation of therapy. The short-term drugs for treating obesity per se are sympathomimetics, with phentermine being most widely used. The second group of drugs is for weight-centric prescribing for patients with a chronic disease such as diabetes, depression, or psychiatric disorders. For each disorder, some drugs produce weight gain, others are weight neutral, but the best choice for these patients is the combination of drugs that treat the underlying condition and also produce weight loss.

The use of the reinstatement model to study relapse to palatable food seeking during dieting

Excessive consumption of unhealthy foods is a major public health problem. While many people attempt to control their food intake through dieting, many relapse to unhealthy eating habits within a few months. We have begun to study this clinical condition in rats by adapting the reinstatement model, which has been used extensively to study relapse to drug seeking. In our adaptation of the relapse model, reinstatement of palatable food seeking by exposure to food-pellet priming, food-associated cues, or stress is assessed in food-restricted (to mimic dieting) rats after operant food-pellet self-administration training and subsequent extinction of the food-reinforced responding. In this review, we first outline the clinical problem and discuss a recent study in which we assessed the predictive validity of the reinstatement model for studying relapse to food seeking during dieting by using the anorexigenic drug fenfluramine. Next, we summarize results from our initial studies on the role of several stress- and feeding-related peptides (corticotropin-releasing factor, hypocretin, melanin-concentrating hormone, peptide YY3-36) in reinstatement of palatable food seeking. We then present results from our studies on the role of dopamine and medial prefrontal cortex in stress-induced reinstatement of food seeking. We conclude by discussing potential clinical implications. We offer two main conclusions: (1) the food reinstatement model is a simple, reliable, and valid model to study mechanisms of relapse to palatable food seeking during dieting, and to identify medications to prevent this relapse; (2) mechanisms of relapse to food seeking are often dissociable from mechanisms of ongoing food intake. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'.

New and emerging drug molecules against obesity

Obesity has become a growing pandemic of alarming proportions in the developed and developing countries over the last few decades. The most perturbing fact regarding obesity is the increased predisposition for coronary artery disease, congestive heart failure and sudden cardiac death. The modest efficacy of current anti-obesity agents such as orlistat and the increasing withdrawals of several anti-obesity agents such as sibutramine, rimonabant have led to huge gaps in the pharmacotherapy of obesity. Lorcaserin and Phentermine-topiramate combination (phen-top) are two drugs approved by US FDA in 2012. Lorcaserin, a 5HT2C agonist has moderate efficacy with an acceptable safety profile. Clinical trials with Phen-top have shown a reasonable efficacy but at the cost of risks such as teratogenicity and psychiatric disturbances. Cetilistat, a lipase inhibitor is claimed to have superior safety profile to orlistat and is in phase 3 clinical trials. Other promising anti-obesity molecules acting on the gut which are in clinical trials include exenatide and liraglutide. Drugs which act on the monoaminergic and opioid systems include bupropion-naltrexone and bupropion-zonisamide. Other novel first-in-class drugs which have been explored and have limited success in early clinical development include velneperit, tesofensine, and beloranib. Tesofensine is a triple monoamine re-uptake inhibitor, velneperit acts as a neuropeptide Y5 receptor antagonist and beloranib is a methionine amino peptidase 2 inhibitor. Novel targets such as histamine H3 receptor, VEGF, matrix-metalloproteinase, sirtuin receptors are also being investigated. This review is an attempt to describe the new and emerging molecules that are in clinical development for obesity.

Obesity pharmacotherapy: current perspectives and future directions

The rising tide of obesity and its related disorders is one of the most pressing health concerns worldwide, yet existing medicines to combat the problem are disappointingly limited in number and effectiveness. Recent advances in mechanistic insights into the neuroendocrine regulation of body weight have revealed an expanding list of molecular targets for novel, rationally designed antiobesity pharmaceutical agents. Antiobesity drugs act via any of four mechanisms: 1) decreasing energy intake, 2) increasing energy expenditure or modulating lipid metabolism, 3) modulating fat stores or adipocyte differentiation, and 4) mimicking caloric restriction. Various novel drug candidates and targets directed against obesity are currently being explored. A few of them are also in the later phases of clinical trials. This review discusses the development of novel antiobesity drugs based on current understanding of energy homeostasis

Updates on Antiobesity Effect of Garcinia Origin (-)-HCA

Garcinia is a plant under the family of Clusiaceae that is commonly used as a flavouring agent. Various phytochemicals including flavonoids and organic acid have been identified in this plant. Among all types of organic acids, hydroxycitric acid or more specifically (−)-hydroxycitric acid has been identified as a potential supplement for weight management and as antiobesity agent. Various in vivo studies have contributed to the understanding of the anti-obesity effects of Garcinia/hydroxycitric acid via regulation of serotonin level and glucose uptake. Besides, it also helps to enhance fat oxidation while reducing de novo lipogenesis. However, results from clinical studies showed both negative and positive antiobesity effects of Garcinia/hydroxycitric acid. This review was prepared to summarise the update of chemical constituents, significance of in vivo/clinical anti-obesity effects, and the importance of the current market potential of Garcinia/hydroxycitric acid.

Food ingredients as anti-obesity agents: a review

Overweight and obesity have a major impact on global health; their prevalence has rapidly increased in all industrialized countries in the past few decades and diabetes and hypertension are their direct consequences. Pharmacotherapy provides reinforcement for obesity treatment, but should be an adjunctive support to diet, exercise, and lifestyle modification. At present, only orlistat and sibutramine have been approved by the US Food and Drug Administration for long-term use, but sibutramine was withdrawn for sale by the European Medicines Agency. The development of functional foods for the prevention and/or treatment of obesity suppose an opportunity for the food market and involve the knowledge of the mechanisms of appetite and energy expenditure as well as the metabolic sensation of satiety. Strategies for weight control management affect gut hormones as potential targets for the appetite metabolic regulation, stimulation of energy expenditure (thermogenesis), and modifications in the metabolic activity of the gut microbiota. Functional foods for obesity may also include bioactive fatty acids, phenolic compounds, soybean, plant sterols, dietary calcium, and dietary fiber. This review intends to offer an overview of the present situation of the anti-obesity agents currently used in dietary therapy as well as some functional food ingredients with potentially anti-obesity effects.

Obesity in bipolar disorder: an overview

Bipolar disorder (BD) is associated with obesity, overweight, and abdominal obesity, and BD individuals with obesity have a greater illness burden. Factors related to BD, its treatment, and the individual may all contribute to BD's association with obesity. Management strategies for the obese BD patient include use of medications with better metabolic profiles, lifestyle interventions, and adjunctive pharmacotherapy for weight loss. Obesity-related psychiatric and medical comorbidities should also be assessed and managed. Bariatric surgery may be an option for carefully selected patients. Greater research into the theoretical underpinnings and clinical management of the BD-obesity connection is needed.

Effect of Bergenia crassifolia L. extracts on weight gain and feeding behavior of rats with high-caloric diet-induced obesity

The objective of this study was to evaluate the feeding behavior and weight gain in rats with high-calorie diet-induced obesity that are treated with Bergenia crassifolia black and fermented leaves extracts. The daily dietary intake of all treated animals was reduced to 40% compared with the control group on day 22 of the experiment. A significant improvement in glucose tolerance was noted after 7 days of treatment with the Bergenia extracts. In rats treated with an extract of black leaves for 7 days, a significant reduction in the serum triglyceride level, 45% (p<0.05), compared with the control group was observed. However, the treatment did not affect the cholesterol level. Our results provide evidence for the potential use of B. crassifolia as an appetite and energy intake suppressant.

Obesity-programmed mice are rescued by early genetic intervention

Obesity is a chronic metabolic disorder affecting half a billion people worldwide. Major difficulties in managing obesity are the cessation of continued weight loss in patients after an initial period of responsiveness and rebound to pretreatment weight. It is conceivable that chronic weight gain unrelated to physiological needs induces an allostatic regulatory state that defends a supranormal adipose mass despite its maladaptive consequences. To challenge this hypothesis, we generated a reversible genetic mouse model of early-onset hyperphagia and severe obesity by selectively blocking the expression of the proopiomelanocortin gene (Pomc) in hypothalamic neurons. Eutopic reactivation of central POMC transmission at different stages of overweight progression normalized or greatly reduced food intake in these obesity-programmed mice. Hypothalamic Pomc rescue also attenuated comorbidities such as hyperglycemia, hyperinsulinemia, and hepatic steatosis and normalized locomotor activity. However, effectiveness of treatment to normalize body weight and adiposity declined progressively as the level of obesity at the time of Pomc induction increased. Thus, our study using a novel reversible monogenic obesity model reveals the critical importance of early intervention for the prevention of subsequent allostatic overload that auto-perpetuates obesity.

Sibutramine effects on central mechanisms regulating energy homeostasis

During the last 50 years the global pandemic of obesity and associated life-threatening co-morbidities strongly promoted the development of anti-obesity pharmacotherapy. Sibutramine is an anti-obesity drug that in conjunction with lifestyle modifications reduces food intake and body weight. This may result from several effects: inhibition of presynaptic reuptake of monoaminergic neurotransmitters in the central nervous system, thereby suppressing appetite, induction of an increase in anorexigenic and a decrease in orexigenic neuropeptide secretion, induction of an increase in energy expenditure, and induction of peripheral sympathomimetic effects. The effects of sibutramine on anabolic and catabolic signals that regulate energy homeostasis in the hypothalamus are not completely understood. So, the aim of this review is to summarize the central mechanisms of action of sibutramine, responsible for its weight and food intake reducing potential. Despite being a useful drug in obesity treatment, awareness about the loss of long-term effectiveness and detrimental side effects of sibutramine has recently emerged. As a consequence, new drugs that produce safer and more persistent weight loss are currently undergoing clinical trials.

Anti-obesity drugs: past, present and future

The ideal anti-obesity drug would produce sustained weight loss with minimal side effects. The mechanisms that regulate energy balance have substantial built-in redundancy, overlap considerably with other physiological functions, and are influenced by social, hedonic and psychological factors that limit the effectiveness of pharmacological interventions. It is therefore unsurprising that anti-obesity drug discovery programmes have been littered with false starts, failures in clinical development, and withdrawals due to adverse effects that were not fully appreciated at the time of launch. Drugs that target pathways in metabolic tissues, such as adipocytes, liver and skeletal muscle, have shown potential in preclinical studies but none has yet reached clinical development. Recent improvements in the understanding of peptidergic signalling of hunger and satiety from the gastrointestinal tract mediated by ghrelin, cholecystokinin (CCK), peptide YY (PYY) and glucagon-like peptide-1 (GLP-1), and of homeostatic mechanisms related to leptin and its upstream pathways in the hypothalamus, have opened up new possibilities. Although some have now reached clinical development, it is uncertain whether they will meet the strict regulatory hurdles required for licensing of an anti-obesity drug. However, GLP-1 receptor agonists have already succeeded in diabetes treatment and, owing to their attractive body-weight-lowering effects in humans, will perhaps also pave the way for other anti-obesity agents. To succeed in developing drugs that control body weight to the extent seen following surgical intervention, it seems obvious that a new paradigm is needed. In other therapeutic arenas, such as diabetes and hypertension, lower doses of multiple agents targeting different pathways often yield better results than strategies that modify one pathway alone. Some combination approaches using peptides and small molecules have now reached clinical trials, although recent regulatory experience suggests that large challenges lie ahead. In future, this polytherapeutic strategy could possibly rival surgery in terms of efficacy, safety and sustainability of weight loss.

Desipramine inhibits histamine H1 receptor-induced Ca2+ signaling in rat hypothalamic cells

The hypothalamus in the brain is the main center for appetite control and integrates signals from adipose tissue and the gastrointestinal tract. Antidepressants are known to modulate the activities of hypothalamic neurons and affect food intake, but the cellular and molecular mechanisms by which antidepressants modulate hypothalamic function remain unclear. Here we have investigated how hypothalamic neurons respond to treatment with antidepressants, including desipramine and sibutramine. In primary cultured rat hypothalamic cells, desipramine markedly suppressed the elevation of intracellular Ca(2+) evoked by histamine H1 receptor activation. Desipramine also inhibited the histamine-induced Ca(2+) increase and the expression of corticotrophin-releasing hormone in hypothalamic GT1-1 cells. The effect of desipramine was not affected by pretreatment with prazosin or propranolol, excluding catecholamine reuptake activity of desipramine as an underlying mechanism. Sibutramine which is also an antidepressant but decreases food intake, had little effect on the histamine-induced Ca(2+) increase or AMP-activated protein kinase activity. Our results reveal that desipramine and sibutramine have different effects on histamine H1 receptor signaling in hypothalamic cells and suggest that distinct regulation of hypothalamic histamine signaling might underlie the differential regulation of food intake between antidepressants.

Long-term safety, tolerability, and weight loss associated with metformin in the Diabetes Prevention Program Outcomes Study

OBJECTIVE

Metformin produced weight loss and delayed or prevented diabetes in the Diabetes Prevention Program (DPP). We examined its long-term safety and tolerability along with weight loss, and change in waist circumference during the DPP and its long-term follow-up.

RESEARCH DESIGN AND METHODS

The randomized double-blind clinical trial of metformin or placebo followed by a 7-8-year open-label extension and analysis of adverse events, tolerability, and the effect of adherence on change in weight and waist circumference.

RESULTS

No significant safety issues were identified. Gastrointestinal symptoms were more common in metformin than placebo participants and declined over time. During the DPP, average hemoglobin and hematocrit levels were slightly lower in the metformin group than in the placebo group. Decreases in hemoglobin and hematocrit in the metformin group occurred during the first year following randomization, with no further changes observed over time. During the DPP, metformin participants had reduced body weight and waist circumference compared with placebo (weight by 2.06 ± 5.65% vs. 0.02 ± 5.52%, P < 0.001, and waist circumference by 2.13 ± 7.06 cm vs. 0.79 ± 6.54 cm, P < 0.001 in metformin vs. placebo, respectively). The magnitude of weight loss during the 2-year double-blind period was directly related to adherence (P < 0.001). Throughout the unblinded follow-up, weight loss remained significantly greater in the metformin group than in the placebo group (2.0 vs. 0.2%, P < 0.001), and this was related to the degree of continuing metformin adherence (P < 0.001).

CONCLUSIONS

Metformin used for diabetes prevention is safe and well tolerated. Weight loss is related to adherence to metformin and is durable for at least 10 years of treatment.