Orlistat

Graphene oxide as inhibitor on the hydrolysis of fats under simulated in vitro duodenal conditions

Obesity is a global pandemic, thus novel developments that reduce the absorption of fats is of interest. We have evaluated the effect of graphene oxide (GO) on the lipase catalyzed hydrolysis of fats (tributyrin, sunflower and olive oil) under simulated duodenal conditions. Results indicate that the presence of GO in the digestion mixture can inhibit lipase activity up to a 90% of the initial reaction rate, and this inhibition lasts even during 2 h of digestion. The inhibition mechanism seems non competitive and could be opposite to the effect of bile salts, although the direct interaction between GO and the enzyme cannot be discarded. The inhibition is found also in alimentary fats suggesting that GO could be a strong inhibitor for fat hydrolysis.

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

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

Pharmacotherapy before and after bariatric surgery

Diabetes is a chronic disease that affects a vast number of individuals globally, and without optimal treatment, can lead to significant health complications. Moreover, obesity is another chronic disease with several complications, which includes type 2 diabetes. Bariatric surgery is a viable long-term choice for managing diseases such as obesity and type 2 diabetes. However, the impact of pharmacotherapy before and after surgery remains unclear. In this review, we assessed the use of pharmacotherapy in patients with obesity with or without diabetes before and after bariatric surgery, focusing on weight loss, glycemic control, and the risk of postoperative complications. We showed that anti-obesity medication has become increasingly important in managing obesity and type 2 diabetes, both before and after bariatric surgery. The use of preoperative pharmacotherapy can optimize patients for surgery and reduce perioperative complications. Meanwhile, postoperative pharmacotherapy can maximize weight loss, improve metabolic outcomes, and lower the risk of weight regain. Medications such as sodium-glucose cotransporter 2 (SGLT2) inhibitors, glucagon-like peptide 1 (GLP-1) receptor agonists, and combination therapies, are now very effective for treating obesity and type 2 diabetes mellitus. However, optimal timing, duration, and which combinations of pharmacotherapy to use with bariatric surgery remain unclear. Additionally, the long-term safety and efficacy of these treatments should be assessed. Integrating pharmacotherapy with bariatric surgery is a promising approach to managing obesity and type 2 diabetes, providing patients with additional options for achieving sustainable weight loss and improving their metabolic health.

Exploring the anti-obesity bioactive compounds of Thymelaea hirsuta and Ziziphus spina-christi through integration of lipase inhibition screening and molecular docking analysis

Activity-guided fractionation of the ethanolic extracts of Thymelaea hirsuta and Ziziphus spina-christi furnished eight compounds with pancreatic lipase inhibitory activity. Six compounds were isolated from the chloroform fraction of T. hirsuta. It is worth mentioning that this is the first report for the isolation of 5,7,4'-trihydroxy-8-methoxycarbonyl flavanol (2), daphnodorin G-3''-methyl ether (4) and daphnodorin G (5) from genus Thymelaea. Moreover, daphnoretin (1), neochamaejasmin A (3) and daphnodorin B (6) were also isolated from the chloroform fraction of the same plant. On the other hand, quercetin 3-O-α-l-rhamnopyranosyl-(1 → 2)-[α-l-rhamnopyranosyl-(1 → 6)]-β-d-galactopyranoside (7) and 3-O-[α-l-fucopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 3)-α-l-arabinopyranosyl] jujubogenin (christinin A) (8) were isolated from the n-butanol fraction of Z. spina-christi. Structure elucidation of the isolated compounds was carried out by detailed analysis of 1D and 2D spectral data. These compounds showed percentage inhibitions of 72% (1), 52% (2), 61.8% (3), 39% (4), 69.5% (5), 3.5% (6), 68% (7) and 75% (8) at the concentration of 250 μM and XP-G scores of lipase inhibition were 11.40 (1), 8.71 (2), 6.13 (3), 8.23 (4), 6.22 (5), 9.76 (6), 14.66 (7) and 12.00 (8). This is the first report of the isolation of lipase inhibitors from both plants T. hirsuta and Z. spina-christi. In addition to that, this might result in presenting the biscoumarin, daphnoretin, and the dammarane saponin, christinin A, as potent lipase inhibitors.

A large-scale genome-wide cross-trait analysis reveals shared genetic architecture between Alzheimer's disease and gastrointestinal tract disorders

Consistent with the concept of the gut-brain phenomenon, observational studies suggest a relationship between Alzheimer's disease (AD) and gastrointestinal tract (GIT) disorders; however, their underlying mechanisms remain unclear. Here, we analyse several genome-wide association studies (GWAS) summary statistics (N = 34,652-456,327), to assess the relationship of AD with GIT disorders. Findings reveal a positive significant genetic overlap and correlation between AD and gastroesophageal reflux disease (GERD), peptic ulcer disease (PUD), gastritis-duodenitis, irritable bowel syndrome and diverticulosis, but not inflammatory bowel disease. Cross-trait meta-analysis identifies several loci (P_{meta-analysis} < 5 × 10^-8) shared by AD and GIT disorders (GERD and PUD) including PDE4B, BRINP3, ATG16L1, SEMA3F, HLA-DRA, SCARA3, MTSS2, PHB, and TOMM40. Colocalization and gene-based analyses reinforce these loci. Pathway-based analyses demonstrate significant enrichment of lipid metabolism, autoimmunity, lipase inhibitors, PD-1 signalling, and statin mechanisms, among others, for AD and GIT traits. Our findings provide genetic insights into the gut-brain relationship, implicating shared but non-causal genetic susceptibility of GIT disorders with AD's risk. Genes and biological pathways identified are potential targets for further investigation in AD, GIT disorders, and their comorbidity.

Regulation of appetite-related neuropeptides by Panax ginseng: A novel approach for obesity treatment

Obesity is a primary factor provoking various chronic disorders, including cardiovascular disease, diabetes, and cancer, and causes the death of 2.8 million individuals each year. Diet, physical activity, medications, and surgery are the main therapies for overweightness and obesity. During weight loss therapy, a decrease in energy stores activates appetite signaling pathways under the regulation of neuropeptides, including anorexigenic [corticotropin-releasing hormone, proopiomelanocortin (POMC), cholecystokinin (CCK), and cocaine- and amphetamine-regulated transcript] and orexigenic [agouti-related protein (AgRP), neuropeptide Y (NPY), and melanin-concentrating hormone] neuropeptides, which increase food intake and lead to failure in attaining weight loss goals. Ginseng and ginsenosides reverse these signaling pathways by suppressing orexigenic neuropeptides (NPY and AgRP) and provoking anorexigenic neuropeptides (CCK and POMC), which prevent the increase in food intake. Moreover, the results of network pharmacology analysis have revealed that constituents of ginseng radix, including campesterol, beta-elemene, ginsenoside Rb1, biotin, and pantothenic acid, are highly correlated with neuropeptide genes that regulate energy balance and food intake, including ADIPOQ, NAMPT, UBL5, NUCB2, LEP, CCK, GAST, IGF1, RLN1, PENK, PDYN, and POMC. Based on previous studies and network pharmacology analysis data, ginseng and its compounds may be a potent source for obesity treatment by regulating neuropeptides associated with appetite.

Effects of oral contraceptives plus orlistat in patients with polycystic ovary syndrome and overweight/obesity: A meta-analysis

AIM

This meta-analysis was conducted to compare the effect and safety of oral contraceptive pills (OCP) plus orlistat with OCP alone in clinical, hormonal, and lipid metabolism outcomes in patients with polycystic ovary syndrome (PCOS) and overweight/obesity.

METHODS

Pubmed, Embase, Web of Science, Chinese National Knowledge Infrastructure (CNKI), and SinoMed were systematically reviewed. A random-effects or fixed-effects model was used to pool the estimate.

RESULTS

Eight studies were included in this meta-analysis. Significant reductions in BMI, WHR, and waist circumference were observed in combination group as compared with OCP alone group. Regarding the hormonal outcome, T, SHBG, FAI, LH, DHEAS, FSH, and E2 levels were significantly improved in combination group compared with OCP alone group. However, the TT and FT did not change significantly between the two groups. Regarding the lipid metabolism outcomes, TC, LDL-C, and TG levels were reduced and HDL-C level was increased in the combination group. Regarding the insulin metabolism outcomes, FINS and HOMA-IR levels were reduced in combination group than in OCP group. The ovulation rate, pregnancy rate, and overall effective rate were significantly higher in combination group than in OCP alone group. Fewer complications were observed in the combination group than in OCP group, and the difference between them was significant.

CONCLUSION

This combination treatment of OCP and orlistat was more effective than OCP alone in reducing the weight, hormonal, lipid, and insulin metabolism profiles, as well as improving the ovulation rate, pregnancy rate, and overall effective rate, as compared with OCP alone.

Physical activity in the management of obesity in adults: A position statement from Exercise and Sport Science Australia

This Position Statement examines the evidence for physical activity in weight and adiposity loss, prevention of weight and adiposity gain, and in weight regain in adults, and provides guidance on implications for exercise practitioners. Research evidence indicates that >150 min but preferably 300 min per week of aerobic activity of at least moderate intensity is required to prevent weight and adiposity gain, and at least the upper end of this range of activity to prevent weight regain after weight loss. For meaningful weight and total adiposity loss, a minimum of 300-420 min per week of aerobic activity of at least moderate intensity is required. The evidence around the volume of aerobic physical activity required to reduce central adiposity is emerging, and research suggests that it may be substantially less than that required for weight loss. The impact of high-intensity physical activity and resistance exercise for weight management is uncertain. During consultations for weight management, exercise practitioners should advise that metabolic and cardiovascular health benefits can be achieved with physical activity at any weight, and irrespective of weight change.

UHPLC-DAD Characterization of Origanum vulgare L. from Atacama Desert Andean Region and Antioxidant, Antibacterial and Enzyme Inhibition Activities

The Lamiaceae family is an important source of species among medicinal plants highly valued for their biological properties and numerous uses in folk medicine. Origanum is one of the main genera that belong to this family. The purpose of the study was to determine the phenolic composition of the Origanum vulgare extract and evaluate the antimicrobial, antioxidant, and inhibitory activities of this species that grows in the Andean region of the Atacama Desert. High-performance liquid chromatography was performed to determine the main phenols. Rosmarinic acid was identified as the predominant phenolic compound in this species (76.01 mg/100 g DW), followed by protocatechuic acid, which to our knowledge, no previous study reported similar concentrations in O. vulgare. The oregano extract exhibited a content of total phenolic (3948 mg GAE/100 g DW) and total flavonoid (593 mg QE/100 g DW) with a higher DPPH antioxidant activity (IC₅₀ = 40.58 µg/mL), compared to the same species grown under other conditions. Furthermore, it was found to inhibit α-glucosidase activity with an IC₅₀ value (7.11 mg/mL) lower than acarbose (129.32 mg/mL). Pseudomonas syringae and Pantoea agglomerans (both MIC 0.313 mg/mL and MBC 1.25 mg/mL) were the bacteria most susceptible to oregano extract with the lowest concentration necessary to inhibit bacterial growth. These results open the door for the potential use of this plant to manage chronic diseases, and they expand the knowledge of the species cultivated in arid environmental conditions.

Phenotypic Discovery of SB1501, an Anti-obesity Agent, through Modulating Mitochondrial Activity

Obesity has become a pandemic that threatens the quality of life and discovering novel therapeutic agents that can reverse obesity and obesity-related metabolic disorders are necessary. Here, we aimed to identify new anti-obesity agents using a phenotype-based approach. We performed image-based high-content screening with a fluorogenic bioprobe (SF44), which visualizes cellular lipid droplets (LDs), to identify initial hit compounds. A structure-activity relationship study led us to yield a bioactive compound SB1501, which reduces cellular LDs in 3T3-L1 adipocytes without cytotoxicity. SB1501 induced the expression of gene products that regulate mitochondrial biogenesis and fatty acid oxidation in 3T3-L1 adipocytes. Daily treatment with SB1501 improved the metabolic states of db/db mice by reducing body fat mass, adipose tissue mass, food intake, and increasing glucose tolerance. The anti-obesity effect of SB1501 may result from perturbation of the PGC-1α-UCP1 regulatory axis in inguinal white adipose tissue and brown adipose tissue. These data suggest the therapeutic potential of SB1501 as an anti-obesity agent via modulating mitochondrial activities.

One-step modification to identify dual-inhibitors targeting both pancreatic triglyceride lipase and Niemann-Pick C1-like 1

Pancreatic triglyceride lipase (PTL) and Niemann-Pick C1-like 1 (NPC1L1) have been identified as attractive therapeutic targets for obesity and hypercholesteremia, respectively. Obesity and hypercholesteremia usually co-exist, however no dual-inhibitors against PTL and NPC1L1 were reported for the treatment of obesity patients with hypercholesteremia so far. In this work, molecular hybridization-based one-step modification screening identified a potent dual-inhibitor against PTL and NPC1L1. Compound P1-11 has IC₅₀ values of 2.1 μM against PTL through covalent binding, as well as significantly reduces cholesterol absorption in a non-competitive inhibitory manner. Molecule docking and molecular dynamics studies revealed the reason of its activity to both PTL and NPC1L1. Moreover, the gene and protein expression levels of PTL and NPC1L1 were also determined respectively after the treatment of P1-11. Development of dual-inhibitors against PTL and NPC1L1 could provide novel treatment options for obesity patients with hypercholesteremia. The results of current research would great support the development of dual-inhibitors against PTL and NPC1L1.

Safety of a Novel Weight Loss Combination Product Containing Orlistat and Acarbose

The safety of a novel modified‐release oral capsule with orlistat and acarbose (MR‐OA) was investigated in 67 obese middle‐aged White men with a body mass index of 32 to 40 kg/m² or 30 to 32 kg/m² plus waist circumference >102 cm. The purpose of this investigation was to compare MR‐OA with the existing conventional orlistat regarding systemic safety defined as plasma orlistat concentration at the end of the treatment period of 14 days. Participants took the MR‐OA fixed‐dose combination formulation 3 times a day together with a major meal. Three different doses of MR‐OA were evaluated—60/20, 90/30, and 120/40 (mg orlistat/mg acarbose)—as well as 1 reference group who received the conventional orlistat, Xenical, with 120 mg of orlistat. Blood plasma was sampled on days 1 and 14. The orlistat plasma concentrations of the MR‐OA dose showed a delayed absorption and were lower compared with conventional orlistat at the end of the study. All doses were safe and well tolerated without any unexpected adverse events and no serious adverse events. The delay in the rise of orlistat plasma concentration indicates that the modified‐release properties of the MR‐OA formulation are effective. The systemic exposure of orlistat resulting from MR‐OA was similar, albeit a bit lower than the conventional orlistat with 120 mg of orlistat. We can therefore assume that the safety profile regarding the orlistat moiety of MR‐OA is comparable to the conventional orlistat and a promising approach for weight control in obese patients. Further clinical evaluation is underway.

Use of Silica Based Materials as Modulators of the Lipase Catalyzed Hydrolysis of Fats under Simulated Duodenal Conditions

The effect of silica materials and their functionalization in the lipase catalyzed fat hydrolysis has been scarcely studied. Fifteen silica materials were prepared and their effect on the fat hydrolysis was measured, under simulated duodenal conditions, using the pH-stat method. The materials are composed of the combination of three supports (Stöber massive silica nanoparticles, Stöber mesoporous nanoparticles and UVM-7) and four surface functionalizations (methyl, trimethyl, propyl and octyl). In addition, the non-functionalized materials were tested. The functional groups were selected to offer a hydrophobic character to the material improving the interaction with the fat globules and the lipase. The materials are able to modulate the lipase activity and their effect depending on the support topology and the organic covering, being able to increase or reduce the fat hydrolysis. Depending of the material, relative fat hydrolysis rates of 75 to 140% in comparison with absence of the material were obtained. The results were analyzed by Partial Least Square Regression and suggest that the alkyl modified mesopores are able to improve the fat hydrolysis, by contrast the non-porous nanoparticles and the textural pores tend to induce inhibition. The effects are more pronounced for materials containing long alkyl chains and/or in absence of taurodeoxycholate.

The risk of cardiovascular complications with current obesity drugs

INTRODUCTION

Obesity is associated with an increased risk of cardiovascular morbidity and mortality. Four medications are approved by the US Food and Drug Administration (FDA) for chronic weight management when used as an adjunct to a reduced-calorie diet and increased physical activity in adults. These medications result in clinically significant weight losses, as well as improvements in some cardiometabolic risk factors.

AREAS COVERED

We briefly review the history of anti-obesity medications (AOMs) as related to cardiovascular safety, and summarize weight loss efficacy and cardiovascular data from clinical trials of orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide.

EXPERT OPINION

Current AOMs approved for chronic weight management have generally favorable effects on some cardiometabolic parameters. However, the long-term safety of orlistat, phentermine/topiramate, and naltrexone/bupropion on cardiovascular morbidity and mortality have not been established. The cardiovascular safety of liraglutide, at a dose of 1.8 mg/d, was demonstrated in a large randomized outcomes trial in participants with type 2 diabetes.

Obesity and Reproduction

OBJECTIVE

To provide a comprehensive review and evidence-based recommendations for the delivery of fertility care to women with obesity.

OUTCOMES

The impact of obesity on fertility, fertility treatments, and both short and long-term maternal fetal outcomes was carefully considered.

EVIDENCE

Published literature was reviewed through searches of MEDLINE and CINAHL using appropriate vocabulary and key words. Results included systematic reviews, clinical trials, observational studies, clinical practice guidelines, and expert opinions.

VALUES

The Canadian Fertility & Andrology Society (CFAS) is a multidisciplinary, national non-profit society that serves as the voice of reproductive specialists, scientists, and allied health professionals working in the field of assisted reproduction in Canada. The evidence obtained for this guideline was reviewed and evaluated by the Clinical Practice Guideline (CPG) Committee of the CFAS under the leadership of the principal authors.

BENEFITS, HARMS, AND COSTS

The implementation of these recommendations should assist clinicians and other health care providers in counselling and providing reproductive care to women with obesity.

VALIDATION

This guideline and its recommendations have been reviewed and approved by the membership, the CPG Committee and the Board of Directors of the CFAS.

SPONSORS

Canadian Fertility & Andrology Society.

RECOMMENDATIONS

Twenty-one evidence based recommendations are provided. These recommendations specifically evaluate the impact of obesity on natural fertility, fertility treatments, and maternal-fetal outcomes. Strategies to lose weight and BMI cut-offs are also addressed.

Slowing down lipolysis significantly enhances the oral absorption of intact solid lipid nanoparticles

Only a limited amount of orally administered lipid nanoparticles are absorbed as intact particles due to lipolysis by lipases in the gastrointestinal tract. It is hypothesized that by counteracting lipolysis, more particles will survive gastrointestinal digestion and be absorbed as intact particles. In this study, incorporation of a lipase inhibitor orlistat (OLST), as well as polyethylene glycol (PEG) coating, is employed to slow down the lipolysis using solid lipid nanoparticles (SLNs) as model particles. To explore the in vivo behaviors of the particles, near-infrared fluorescent probes with absolute aggregation-caused quenching (ACQ) properties are used to label and track the unmodified, PEG-coated and OLST-loaded SLNs. The in vitro lipolysis study indicates very fast first-order degradation of unmodified SLNs and significantly decreased degradation of OLST-SLNs. Live imaging reveals the same trend of slowed-down lipolysis in vivo which correlates well with the in vitro lipolysis. The scanning of ex vivo gastrointestinal segments confirms the considerably prolonged residence time of OLST-SLNs, mirroring the significantly decreased lipolysis rate. The observation of fluorescence in the blood, though very weak, and in the liver speaks of the oral absorption of intact SLNs. The substantially higher hepatic levels of OLST-SLNs than unmodified SLNs should be attributed to the significantly enhanced survival rate because both particles exhibit similar cellular recognition as well as similar physicochemical properties except for the survival rate. Similarly, slowing down lipolysis also contributes to the significantly enhanced cumulative lymphatic transport of OLST-SLNs (7.56% vs. 1.27% for the unmodified SLNs). The PEG coating slows down the lipolysis rate as well but not to the degree as done by OLST. As a result, the gastrointestinal residence time of PEG-SLNs has been moderately prolonged and the hepatic levels moderately increased. The weakened cellular recognition of PEG-SLNs implies that the enhanced oral absorption is solely ascribed to the slowed-down lipolysis and enhanced mucus penetration. In conclusion, the oral absorption of intact SLNs can be significantly enhanced by slowing down lipolysis, especially by OLST, showing potential as carriers for the oral delivery of labile biomacromolecules.

Pharmacologic therapy to induce weight loss in women who have obesity/overweight with polycystic ovary syndrome: a systematic review and network meta-analysis

BACKGROUND

Women with polycystic ovary syndrome (PCOS) are almost three times more likely to be obese than those without PCOS. However, we have no specific interventions to induce weight loss so far and rely on drugs used to treat other symptoms of the syndrome or obesity in the general population.

OBJECTIVE

The objective of this study is to compare the effectiveness of metformin, inositol, liraglutide and orlistat to induce weight loss in women with PCOS and overweight/obesity.

METHODS

A search was conducted using the MEDLINE, EMBASE, PubMed and CENTRAL databases. Individually randomized, parallel group trials that evaluated the effects of these pharmacological treatments among adults or adolescents with PCOS and overweight/obesity, compared with a placebo or metformin group, were considered eligible. Registration number: PROSPERO CRD 42017076625.

RESULTS

Twenty-three trials reporting on 941 women were included in the network meta-analysis. The amount of weight lost differed significantly among the drugs (in descending order): liraglutide, orlistat and metformin. Liraglutide alone, liraglutide/metformin and metformin alone significantly reduced waist circumference, but no change was found with orlistat. Data for waist-to-hip ratio were only available for metformin, which had no significant effect.

CONCLUSION

Liraglutide appears superior to the other drugs in reducing weight and waist circumference.

Role of Cannabinoids in Obesity

Obesity is an increasing health problem worldwide. Its related comorbidities imply a high cost for the National Health System and diminish a patient's life quality. Adipose tissue is composed of three types of cells. White adipocytes are involved in fat storage and secretion of hormones. Brown adipocytes are involved in thermogenesis and caloric expenditure. Beige adipocytes are transitional adipocytes that in response to various stimuli can turn from white to brown and could be protective against the obesity, enhancing energy expenditure. The conversion of white in beige adipose tissue is a potential new therapeutic target for obesity. Cannabinoid receptors (CB) regulate thermogenesis, food intake and inflammation. CB1 ablation or inhibition helps reducing body weight and food intake. Stimulation of CB2 limits inflammation and promotes anti-obesity effects by reducing food intake and weight gain. Its genetic ablation results in adiposity development. CB receptors are also responsible for transforming white adipose tissue towards beige or brown adipocytes, therefore their modulation can be considered potential anti-obesity target. CB1 principal localization in central nervous system represents an important limit. Stimulation of CB2, principally localized on peripheral cells instead, should facilitate the anti-obesity effects without exerting remarkable psychotropic activity.

Deciphering T Cell Immunometabolism with Activity-Based Protein Profiling

As a major sentinel of adaptive immunity, T cells seek and destroy diseased cells using antigen recognition to achieve molecular specificity. Strategies to block checkpoint inhibition of T cell activity and thus reawaken the patient's antitumor immune responses are rapidly becoming standard of care for treatment of diverse cancers. Adoptive transfer of patient T cells genetically engineered with tumor-targeting capabilities is redefining the field of personalized medicines. The diverse opportunities for exploiting T cell biology in the clinic have prompted new efforts to expand the scope of targets amenable to immuno-oncology. Given the complex spatiotemporal regulation of T cell function and fate, new technologies capable of global molecular profiling in vivo are needed to guide selection of appropriate T cell targets and subsets. In this chapter, we describe the use of activity-based protein profiling (ABPP) to illuminate different aspects of T cell metabolism and signaling as fertile starting points for investigation. We highlight the merits of ABPP methods to enable target, inhibitor, and biochemical pathway discovery of T cells in the burgeoning field of immuno-oncology.

Identification of a S. aureus virulence factor by activity-based protein profiling (ABPP)

Serine hydrolases play diverse roles in regulating host-pathogen interactions in a number of organisms, yet few have been characterized in the human pathogen Staphylococcus aureus. Here we describe a chemical proteomic screen that identified ten previously uncharacterized S. aureus serine hydrolases that mostly lack human homologs. We termed these enzymes fluorophosphonate-binding hydrolases (FphA-J). One hydrolase, FphB, can process short fatty acid esters, exhibits increased activity in response to host cell factors, is located predominantly on the bacterial cell surface in a subset of cells, and is concentrated in the division septum. Genetic disruption of fphB confirmed that the enzyme is dispensable for bacterial growth in culture but crucial for establishing infection in distinct sites in vivo. A selective small molecule inhibitor of FphB effectively reduced infectivity in vivo, suggesting that it may be a viable therapeutic target for the treatment or management of Staphylococcus infections.

Orlistat as a FASN inhibitor and multitargeted agent for cancer therapy

INTRODUCTION

Cancer cells have increased glycolysis and glutaminolysis. Their third feature is increased de novo lipogenesis. As such, fatty acid (FA) synthesis enzymes are over-expressed in cancer and their depletion causes antitumor effects. As fatty acid synthase (FASN) plays a pivotal role in this process, it is an attractive target for cancer therapy.

AREAS COVERED

This is a review of the lipogenic phenotype of cancer and how this phenomenon can be exploited for cancer therapy using inhibitors of FASN, with particular emphasis on orlistat as a repurposing drug.

EXPERT OPINION

Disease stabilization only has been observed with a highly selective FASN inhibitor used as a single agent in clinical trials. It is too early to say whether the absence of tumor responses other than stabilization results because even full inhibition of FASN is not enough to elicit antitumor responses. The FASN inhibitor orlistat is a 'dirty' drug with target-off actions upon at least seven targets with a proven role in tumor biology. The development of orlistat formulations suited for its intravenous administration is a step ahead to shed light on the concept that drug promiscuity can or not be a virtue.

Efficacy and Safety of Cathine (Nor-Pseudoephedrine) in the Treatment of Obesity: A Randomized Dose-Finding Study

OBJECTIVE

To investigate the efficacy and safety of increasing doses of cathine (nor-pseudoephedrine) as a weight-lowering agent in patients with obesity.

METHODS

Overweight and obese patients (n = 241, mean BMI 34.6 ± 3.4 kg/m²) were randomly allocated to one of three doses of cathine (16 mg, 32 mg, 53.3 mg) or placebo in addition to a multimodal lifestyle intervention program in a multicenter, double-blind, controlled, dose-finding study for 24 weeks. Primary outcome was weight loss.

RESULTS

Treatment with the 3 doses of cathine resulted in a significantly greater weight loss compared to placebo over 24 weeks: 6.5 ± 4.2 kg for 16 mg cathine, 6.2 ± 4.7 kg for 32 mg cathine, and 9.1 ± 5.4 kg for 53.3 mg cathine versus 2.4 ± 4.4 kg for placebo (each p < 0.01, ANCOVA). The percentage of patients losing > 5% / >10% of initial body weight was significantly greater for all doses of cathine than for placebo (each p < 0.01, chi-square test). Heart rate increased dose-dependently (by 1.2 bpm under 16 mg, 5.8 bpm under 32 mg, and 6.2 bpm under 53.3 mg cathine), but no suspected unexpected serious adverse reactions were noted. The overall dropout rate was 24.9%, with the highest rate in the placebo group (42.3%).

CONCLUSION

Cathine appears to be an effective weight-lowering agent for adjunct treatment of obesity, but additional clinical studies on its efficacy and safety are required.

A Bioactivity-Based Method for Screening, Identification of Lipase Inhibitors, and Clarifying the Effects of Processing Time on Lipase Inhibitory Activity of Polygonum Multiflorum

Traditional Chinese medicine (TCM) has been used for the treatment of many complex diseases. However, the bioactive components are always undefined. In this study, a bioactivity-based method was developed and validated to screen lipase inhibitors and evaluate the effects of processing on the lipase inhibitory activity of TCM by ultrahigh performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry and fraction collector (UHPLC/Q-TOF-MS-FC). The results showed that both Polygonum multiflorum and processed P. multiflorum extracts had inhibitory effect against lipase with IC50 values of 38.84 μg/mL and 190.6 μg/mL, respectively. Stilbenes, phenolic acid, flavonoids, and anthraquinones were considered to be the potential lipase inhibitors. Eleven potential lipase inhibitors were simultaneously determined by UHPLC. Principal component analysis (PCA) was employed in exploring the effects of processing time on lipase inhibitory activity of P. multiflorum. Compared with conventional methods, a bioactivity-based method could quantitatively analyze lipase inhibitory activity of individual constituent and provide the total lipase inhibitory activity of the samples. The results demonstrated that the activity integrated UHPLC/Q-TOF-MS-FC method was an effective and powerful tool for screening and identifying lipase inhibitors from traditional Chinese medicines.

Activity-based protein profiling: an efficient approach to study serine hydrolases and their inhibitors in mammals and microbes

This review focuses on the identification of serine hydrolases and their inhibitors in mammals and microbes with activity-based protein profiling (ABPP).

Orlistat limits cholesterol intestinal absorption by Niemann-pick C1-like 1 (NPC1L1) inhibition

The known mechanism by which orlistat decreases the absorption of dietary cholesterol is by inhibition of intestinal lipases. The aim of this study was to investigate the ability of orlistat to limit cholesterol absorption by inhibition of the cholesterol transport protein Niemann-Pick C1-like 1 (NPC1L1) as another mechanism of action. In situ rat intestinal perfusion studies were conducted to study the effect of orlistat on jejunal cholesterol absorption. Inhibition kinetic parameters were calculated from in vitro inhibition studies using Caco2 and NPC1L1 transfected cell lines. The in situ studies demonstrated that intestinal perfusion of orlistat (100µM) was able to reduce cholesterol absorption by three-fold when compared to control (i.e. in the absence of orlistat, P<0.01). In vitro studies using Caco2 cells demonstrated orlistat to reduce the cellular uptake of cholesterol by 30%. Additionally, orlistat reduced the cellular uptake of cholesterol in dose dependent manner in NPC1L1 transfected cell line with an IC50=1.2µM. Lineweaver-Burk plot indicated a noncompetitive inhibition of NPC1L1 by orlistat. Beside the already established mechanism by which orlistat reduces the absorption of cholesterol, we demonstrated for the first time that orlistat limits cholesterol absorption by the inhibition of NPC1L1 transport protein.

Secondary hypertriglyceridemia in children and adolescents

Secondary dyslipidemia with predominant hypertriglyceridemia may occur as a consequence of both common and rare causes. After accounting for obesity and associated insulin resistance, clinicians should carefully consider other contributing factors and conditions. Genetic background and causative factors prevail during gestation, infancy, and childhood and continue in adults. Elevations in triglyceride (TG) are associated with transfer of TG to high-density lipoprotein (HDL) and low-density lipoprotein (LDL) resulting in lipolysis, HDL degradation, and formation of atherogenic LDL particles. Defining and treating the underlying cause is the first step toward restoring the lipids and lipoproteins to normal, especially in cases with severe hypertriglyceridemia, who are at risk for acute pancreatitis. Disorders involving the liver, kidney, endocrine, and immune systems and medications need to be considered. Rare diseases such as lipodystrophy and glycogen storage disease are particularly challenging, and there have been promising new developments. Treatment depends on the severity; prevention of acute pancreatitis being a priority in severe cases and lifestyle modification being a foundation for general management followed by targeting TG and predictors of coronary artery disease such as LDL cholesterol and non-HDL cholesterol, when they exceed cutpoints.

Bariatric endocrinology: principles of medical practice

Obesity, is a chronic, biological, preventable, and treatable disease. The accumulation of fat mass causes physical changes (adiposity), metabolic and hormonal changes due to adipose tissue dysfunction (adiposopathy), and psychological changes. Bariatric endocrinology was conceived from the need to address the neuro-endocrinological derangements that are associated with adiposopathy, and from the need to broaden the scope of the management of its complications. In addition to the well-established metabolic complications of overweight and obesity, adiposopathy leads to hyperinsulinemia, hyperleptinemia, hypoadiponectinemia, dysregulation of gut peptides including GLP-1 and ghrelin, the development of an inflammatory milieu, and the strong risk of vascular disease. Therapy for adiposopathy hinges on effectively lowering the ratio of orexigenic to anorexigenic signals reaching the the hypothalamus and other relevant brain regions, favoring a lower caloric intake. Adiposopathy, overweight and obesity should be treated indefinitely with the specific aims to reduce fat mass for the adiposity complications, and to normalize adipose tissue function for the adiposopathic complications. This paper defines the principles of medical practice in bariatric endocrinology-the treatment of overweight and obesity as means to treat adiposopathy and its accompanying metabolic and hormonal derangements.

Modulation of fatty acid synthase enzyme activity and expression during hepatitis C virus replication

The hepatitis C virus (HCV) induces alterations of host cells to facilitate its life cycle. Fatty acid synthase (FASN) is a multidomain enzyme that plays a key role in the biosynthesis of fatty acids and is upregulated during HCV infection. Herein, we applied activity-based protein profiling (ABPP) that allows for the identification of differentially active enzymes in complex proteomic samples, to study the changes in activity of FASN during HCV replication. For this purpose, we used an activity-based probe based on the FASN inhibitor Orlistat, and observed an increase in the activity of FASN in the presence of a subgenomic and a genomic HCV replicon as well as in chimeric SCID/Alb-uPA mice infected with HCV genotype 1a. To study the molecular basis for this increase in FASN activity, we overexpressed individual HCV proteins in Huh7 cells and observed increased expression and activity of FASN in the presence of core and NS4B, as measured by western blots and ABPP, respectively. Triglyceride levels were also elevated in accordance with FASN expression and activity. Lastly, immunofluorescence and ABPP imaging analyses demonstrated that while the abundance and activity of FASN increases significantly in the presence of HCV, its localization does not change. Together these data suggest that the HCV-induced production of fatty acids and neutral lipids is provided by an increase in FASN abundance and activity that is sufficient to allow HCV propagation without transporting FASN to the replication complexes.

Development and optimization of piperidyl-1,2,3-triazole ureas as selective chemical probes of endocannabinoid biosynthesis

We have previously shown that 1,2,3-triazole ureas (1,2,3-TUs) act as versatile class of irreversible serine hydrolase inhibitors that can be tuned to create selective probes for diverse members of this large enzyme class, including diacylglycerol lipase-β (DAGLβ), a principal biosynthetic enzyme for the endocannabinoid 2-arachidonoylglycerol (2-AG). Here, we provide a detailed account of the discovery, synthesis, and structure-activity relationship (SAR) of (2-substituted)-piperidyl-1,2,3-TUs that selectively inactivate DAGLβ in living systems. Key to success was the use of activity-based protein profiling (ABPP) with broad-spectrum and tailored activity-based probes to guide our medicinal chemistry efforts. We also describe an expanded repertoire of DAGL-tailored activity-based probes that includes biotinylated and alkyne agents for enzyme enrichment coupled with mass spectrometry-based proteomics and assessment of proteome-wide selectivity. Our findings highlight the broad utility of 1,2,3-TUs for serine hydrolase inhibitor development and their application to create selective probes of endocannabinoid biosynthetic pathways.

Flaxseed dietary fibers lower cholesterol and increase fecal fat excretion, but magnitude of effect depend on food type

Background

Dietary fibers have been proposed to play a role in cardiovascular risk as well as body weight management. Flaxseeds are a good source of dietary fibers, and a large proportion of these are water-soluble viscous fibers.

Method

Here, we examine the effect of flaxseed dietary fibers in different food matrices on blood lipids and fecal excretion of fat and energy in a double-blind randomized crossover study with 17 subjects. Three different 7-d diets were tested: a low-fiber control diet (Control), a diet with flaxseed fiber drink (3/day) (Flax drink), and a diet with flaxseed fiber bread (3/day) (Flax bread). Total fat and energy excretion was measured in feces, blood samples were collected before and after each period, and appetite sensation registered 3 times daily before main meals.

Results

Compared to control, Flax drink lowered fasting total-cholesterol and LDL-cholesterol by 12 and 15%, respectively, (p < 0.01), whereas Flax bread only produced a reduction of 7 and 9%, respectively (p < 0.05). Fecal fat and energy excretion increased by 50 and 23% with Flax drink consumption compared to control (p < 0.05), but only fecal fat excretion was increased with Flax bread compared to control (p < 0.05).

Conclusion

Both Flax drink and Flax bread resulted in decreased plasma total and LDL-cholesterol and increased fat excretion, but the food matrix and/or processing may be of importance. Viscous flaxseed dietary fibers may be a useful tool for lowering blood cholesterol and potentially play a role in energy balance.

Trial Registration

ClinicalTrials.gov: NCT00953004

Weight loss surgery for morbidly obese adolescents: a review

Obesity is common among adolescents resulting in substantial comorbidities and reduced life expectancy. Conservative treatments normally fail to ensure significant and sustained weight loss and suitable adolescents should be offered weight loss surgery. Laparoscopic Adjustable Gastric Banding and Roux-en-Y Gastric Bypass are commonly used in adolescents. Complications in RYGB tend to be more severe, but the procedure leads to more immediate results. LAGB complications are often device-related and less severe. Dietary adherence, eating behaviour and unrealistic patient expectations often cause problems. Significant and sustained weight loss of 50-70 per cent of excess weight is achievable, comorbidities and psychological problems improve. Meticulous patient selection and preparation and good post-operative care are vital for successful weight loss surgery. Weight loss surgery is safe, effective and economically viable with nurses playing a vital role at all stages of its application.

Central control of thermogenesis

In mammals and birds, conservation of body heat at around 37 °C is vital to life. Thermogenesis is the production of this heat which can be obligatory, as in basal metabolic rate, or it can be facultative such as the response to cold. A complex regulatory system has evolved which senses environmental or core temperature and integrates this information in hypothalamic regions such as the preoptic area and dorsomedial hypothalamus. These areas then send the appropriate signals to generate and conserve heat (or dissipate it). In this review, the importance of the sympathetic nervous system is discussed in relation to its role in basal metabolic rate and adaptive thermogenesis with a particular emphasis to human obesity. The efferent sympathetic pathway does not uniformly act on all tissues; different tissues can receive different levels of sympathetic drive at the same time. This is an important concept in the discussion of the pharmacotherapy of obesity. Despite decades of work the medicine chest contains only one pill for the long term treatment of obesity, orlistat, a lipase inhibitor that prevents the absorption of lipid from the gut and is itself not systemically absorbed. The central controlling system for thermogenesis has many potential intervention points. Several drugs, previously marketed, awaiting approval or in the earlier stages of development may have a thermogenic effect via activation of the sympathetic nervous system at some point in the thermoregulatory circuit and are discussed in this review. If the balance is weighted to the "wrong" side there is the burden of increased cardiovascular risk while a shift to the "right" side, if possible, will afford a thermogenic benefit that is conducive to weight loss maintenance. This article is part of a Special Issue entitled 'Central Control Food Intake'

Click-generated triazole ureas as ultrapotent in vivo-active serine hydrolase inhibitors

Serine hydrolases are a diverse enzyme class representing ∼1% of all human proteins. The biological functions of most serine hydrolases remain poorly characterized owing to a lack of selective inhibitors to probe their activity in living systems. Here we show that a substantial number of serine hydrolases can be irreversibly inactivated by 1,2,3-triazole ureas, which show negligible cross-reactivity with other protein classes. Rapid lead optimization by click chemistry-enabled synthesis and competitive activity-based profiling identified 1,2,3-triazole ureas that selectively inhibit enzymes from diverse branches of the serine hydrolase class, including peptidases (acyl-peptide hydrolase, or APEH), lipases (platelet-activating factor acetylhydrolase-2, or PAFAH2) and uncharacterized hydrolases (α,β-hydrolase-11, or ABHD11), with exceptional potency in cells (sub-nanomolar) and mice (<1 mg kg(-1)). We show that APEH inhibition leads to accumulation of N-acetylated proteins and promotes proliferation in T cells. These data indicate 1,2,3-triazole ureas are a pharmacologically privileged chemotype for serine hydrolase inhibition, combining broad activity across the serine hydrolase class with tunable selectivity for individual enzymes.

Evaluation of efficacy and safety of orlistat in obese patients

CONTEXT

Rapidly rising prevalence of obesity is alarming. Obesity predisposes to co-morbidities like hypertension, type 2 diabetes mellitus, dyslipidemias, thus substantially rising healthcare expenditure. Lifestyle modifications alone have very limited success, necessitating the addition of pharmacotherapy to it.

OBJECTIVE

Present study was carried out to evaluate the efficacy and safety of orlistat in obese patients.

MATERIALS AND METHODS

Eighty obese (BMI>30) patients according to inclusion and exclusion criteria were randomized into either of the two groups. Group 1 received orlistat 120 mg three times a day and group 2 received placebo three times a day. Weight, waist circumference, BMI, total cholesterol, triglycerides, HDL, LDL were measured at baseline and then at 8(th), 16(th) and 24(th) week. ADR reported by patients were recorded. For safety evaluation various hematological and biochemical parameters were assessed. Z test was used for analysis of data.

RESULTS

Compared to placebo, orlistat caused significant reduction (P<0.05) in weight (4.65 kg vs 2.5 kg; orlistat vs placebo, respectively), BMI (1.91 kg/m(2) vs 0.64 kg/m(2)) and waist circumference (4.84 cm vs 2 cm), cholesterol (10.68 mg vs 6.18 mg) and LDL level (5.87 mg vs 2.33 mg). In the orlistat group, the GI side effects like loose stools, oily stools/spotting, abdominal pain and fecal urgency were observed.

CONCLUSION

Orlistat is an effective and well-tolerated antiobesity drug, which can be employed as an adjunct to therapeutic lifestyle changes to achieve and maintain optimal weight.

Weight loss in obese patients with chronic kidney disease: who and how?

Obesity has adverse consequences in the general population. In patients with chronic kidney disease (CKD), it is associated with increased inflammation, insulin resistance, hypertension and dyslipidaemia, which are important risk factors for CKD progression and death. In adults with CKD stages 1-4, weight loss should be encouraged, it reduces proteinuria and glomerular hyperfiltration, which are frequent in obese patients. Proposals for modifications of lifestyle, physical activity and calorie restriction are the first measures. Pharmacological treatments are generally unsafe in these patients, except orlistat, but that has modest efficacy. Bariatric surgery may be the only option in severe obesity, if all other measures fail. For obese patients on dialysis treatment, who are eligible for kidney transplantation, weight loss is mandatory to prevent obesity-related surgical complications and improve patient and graft survival after transplantation. Interventions should place an emphasis on exercise to increase muscle mass, and calorie but not protein restriction. Bariatric surgery should be carried out by experienced surgeons due to the high risk of complications. For obese patients who are not considered transplant candidates the benefits of weight loss remain uncertain.

Study of the interaction of pancreatic lipase with procyanidins by optical and enzymatic methods

The interactions between porcine pancreatic lipase (PL) and grape seed procyanidins were studied by an enzymatic assay, fluorescence quenching, nephelometry, and dynamic light scattering (DLS). An inhibitory effect of grape seed procyanidins on lipase hydrolytic activity was found. Both the inhibition of lipase activity by procyanidins and the respective quenching of intrinsic protein fluorescence increased with the average degree of polymerization of the tested procyanidins. The association between procyanidins and enzyme involves a specific interaction as inferred from the fluorescence assays despite not changing significantly the tertiary structure of the protein. For all tested procyanidins it was shown, both by DLS and by nephelometry, that an increase in aggregation occurs up to a stoichiometric maximum after which further procyanidin addition causes a decrease in aggregation of aggregates. The maximum size of aggregates was shown to be closely related to the maximum overall aggregation. It was also shown that the inhibition of enzyme activity is to a large extent independent of the formation of aggregates.

Superfamily-wide portrait of serine hydrolase inhibition achieved by library-versus-library screening

Serine hydrolases (SHs) are one of the largest and most diverse enzyme classes in mammals. They play fundamental roles in virtually all physiological processes and are targeted by drugs to treat diseases such as diabetes, obesity, and neurodegenerative disorders. Despite this, we lack biological understanding for most of the 110+ predicted mammalian metabolic SHs, in large part because of a dearth of assays to assess their biochemical activities and a lack of selective inhibitors to probe their function in living systems. We show here that the vast majority (> 80%) of mammalian metabolic SHs can be labeled in proteomes by a single, active site-directed fluorophosphonate probe. We exploit this universal activity-based assay in a library-versus-library format to screen 70+ SHs against 140+ structurally diverse carbamates. Lead inhibitors were discovered for ∼40% of the screened enzymes, including many poorly characterized SHs. Global profiles identified carbamate inhibitors that discriminate among highly sequence-related SHs and, conversely, enzymes that share inhibitor sensitivity profiles despite lacking sequence homology. These findings indicate that sequence relatedness is not a strong predictor of shared pharmacology within the SH superfamily. Finally, we show that lead carbamate inhibitors can be optimized into pharmacological probes that inactivate individual SHs with high specificity in vivo.

Rise in antiobesity drug prescribing for children and adolescents in the UK: a population-based study

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

* The antiobesity drugs sibutramine and orlistat are not licensed for use in children and adolescents in the UK or USA. * Clinical trials suggest antiobesity drugs are effective and well-tolerated in obese adolescents.

WHAT THIS STUDY ADDS

* Prescribing of unlicensed antiobesity drugs in children and adolescents has increased significantly in the past 8 years. * Most prescribed antiobesity drugs in children and adolescents are rapidly discontinued before patients can see clinical benefit, suggesting they are poorly tolerated or poorly efficacious.

AIMS

The international childhood obesity epidemic has driven increased use of unlicensed antiobesity drugs, whose efficacy and safety are poorly studied in children and adolescents. We investigated the use of unlicensed antiobesity drugs (orlistat, sibutramine and rimonabant) in children and adolescents (0-18 years) in the UK.

METHODS

Population-based prescribing data from the UK General Practice Research Database between 1 January 1999 and 31 December 2006.

RESULTS

A total of 452 subjects received 1334 prescriptions during the study period. The annual prevalence of antiobesity drug prescriptions rose significantly from 0.006 per 1000 [95% confidence interval (CI) 0.0007, 0.0113] in 1999 to 0.091 per 1000 (95% CI 0.07, 0.11) in 2006, a 15-fold increase, with similar increases seen in both genders. The majority of prescriptions were made to those >or=14 years old, although 25 prescriptions were made for children <12 years old. Orlistat accounted for 78.4% of all prescriptions; only one patient was prescribed rimonabant. However, approximately 45% of the patients ceased orlistat and 25% ceased sibutramine after only 1 month. The estimated mean treatment durations for orlistat and sibutramine were 3 and 4 months, respectively.

CONCLUSIONS

Prescribing of unlicensed antiobesity drugs in children and adolescents has dramatically increased in the past 8 years. The majority are rapidly discontinued before patients can see weight benefit, suggesting they are poorly tolerated or poorly efficacious when used in the general population. Further research into the effectiveness and safety of antiobesity drugs in clinical populations of children and adolescents is needed.

Obesity management in adults with CKD

A 22-year-old African-American woman who has been dialysis dependent for four months due to hypertensive kidney disease is referred for kidney transplantation evaluation. Due to the recent occlusion of her left forearm arteriovenous graft, she is currently being dialyzed via a right internal jugular tunneled catheter. Her medications include methyldopa 250 mg bid, Tums 1000 mg with each meal and erythropoietin with dialysis. The patient is single without children, unemployed and lives with her 38 year old mother. She does not smoke or drink. Her review of systems is unremarkable. On physical exam, her weight is 284 pounds, height is 5 feet 2 inches and her body mass index is 51.9 kg/m2. The blood pressure is 130/80 and the cardiac and pulmonary exams are unremarkable. The surgeon feels she is otherwise a good candidate for transplantation except she must lose weight before being listed. What advice should she be given regarding weight loss?