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Critical Reviews in Food Science and... 2015There has been renewed interest in vitamin D since numerous recent studies have suggested that besides its well-established roles in bone metabolism and immunity,... (Review)
Review
There has been renewed interest in vitamin D since numerous recent studies have suggested that besides its well-established roles in bone metabolism and immunity, vitamin D status is inversely associated with the incidence of several diseases, e.g., cancers, cardio-vascular diseases, and neurodegenerative diseases. Surprisingly, there is very little data on factors that affect absorption of this fat-soluble vitamin, although it is acknowledged that dietary vitamin D could help to fight against the subdeficient vitamin D status that is common in several populations. This review describes the state of the art concerning the fate of vitamin D in the human upper gastrointestinal tract and on the factors assumed to affect its absorption efficiency. The main conclusions are: (i) ergocalciferol (vitamin D2), the form mostly used in supplements and fortified foods, is apparently absorbed with similar efficiency to cholecalciferol (vitamin D3, the main dietary form), (ii) 25-hydroxyvitamin D (25OHD), the metabolite produced in the liver, and which can be found in foods, is better absorbed than the nonhydroxy vitamin D forms cholecalciferol and ergocalciferol, (iii) the amount of fat with which vitamin D is ingested does not seem to significantly modify the bioavailability of vitamin D3, (iv) the food matrix has apparently little effect on vitamin D bioavailability, (v) sucrose polyesters (Olestra) and tetrahydrolipstatin (orlistat) probably diminish vitamin D absorption, and (vi) there is apparently no effect of aging on vitamin D absorption efficiency. We also find that there is insufficient, or even no data on the following factors suspected of affecting vitamin D bioavailability: (i) effect of type and amount of dietary fiber, (ii) effect of vitamin D status, and (iii) effect of genetic variation in proteins involved in its intestinal absorption. In conclusion, further studies are needed to improve our knowledge of factors affecting vitamin D absorption efficiency. Clinical studies with labeled vitamin D, e.g., deuterated or (13)C, are needed to accurately and definitively assess the effect of various factors on its bioavailability.
Topics: Aging; Biological Availability; Cholecalciferol; Dietary Supplements; Ergocalciferols; Fatty Acids; Food, Fortified; Humans; Intestinal Absorption; Lactones; Orlistat; Risk Factors; Sucrose; Vitamin D
PubMed: 24915331
DOI: 10.1080/10408398.2012.688897 -
JAMA Jun 2016Five medications have been approved for the management of obesity, but data on comparative effectiveness are limited. (Meta-Analysis)
Meta-Analysis Review
IMPORTANCE
Five medications have been approved for the management of obesity, but data on comparative effectiveness are limited.
OBJECTIVE
To compare weight loss and adverse events among drug treatments for obesity using a systematic review and network meta-analysis.
DATA SOURCES
MEDLINE, EMBASE, Web of Science, Scopus, and Cochrane Central from inception to March 23, 2016; clinical trial registries.
STUDY SELECTION
Randomized clinical trials conducted among overweight and obese adults treated with US Food and Drug Administration-approved long-term weight loss agents (orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, or liraglutide) for at least 1 year compared with another active agent or placebo.
DATA EXTRACTION AND SYNTHESIS
Two investigators identified studies and independently abstracted data using a predefined protocol. A Bayesian network meta-analysis was performed and relative ranking of agents was assessed using surface under the cumulative ranking (SUCRA) probabilities. Quality of evidence was assessed using GRADE criteria.
MAIN OUTCOMES AND MEASURES
Proportions of patients with at least 5% weight loss and at least 10% weight loss, magnitude of decrease in weight, and discontinuation of therapy because of adverse events at 1 year.
RESULTS
Twenty-eight randomized clinical trials with 29 018 patients (median age, 46 years; 74% women; median baseline body weight, 100.5 kg; median baseline body mass index, 36.1) were included. A median 23% of placebo participants had at least 5% weight loss vs 75% of participants taking phentermine-topiramate (odds ratio [OR], 9.22; 95% credible interval [CrI], 6.63-12.85; SUCRA, 0.95), 63% of participants taking liraglutide (OR, 5.54; 95% CrI, 4.16-7.78; SUCRA, 0.83), 55% taking naltrexone-bupropion (OR, 3.96; 95% CrI, 3.03-5.11; SUCRA, 0.60), 49% taking lorcaserin (OR, 3.10; 95% CrI, 2.38-4.05; SUCRA, 0.39), and 44% taking orlistat (OR, 2.70; 95% CrI, 2.34-3.09; SUCRA, 0.22). All active agents were associated with significant excess weight loss compared with placebo at 1 year-phentermine-topiramate, 8.8 kg (95% CrI, -10.20 to -7.42 kg); liraglutide, 5.3 kg (95% CrI, -6.06 to -4.52 kg); naltrexone-bupropion, 5.0 kg (95% CrI, -5.94 to -3.96 kg); lorcaserin, 3.2 kg (95% CrI, -3.97 to -2.46 kg); and orlistat, 2.6 kg (95% CrI, -3.04 to -2.16 kg). Compared with placebo, liraglutide (OR, 2.95; 95% CrI, 2.11-4.23) and naltrexone-bupropion (OR, 2.64; 95% CrI, 2.10-3.35) were associated with the highest odds of adverse event-related treatment discontinuation. High attrition rates (30%-45% in all trials) were associated with lower confidence in estimates.
CONCLUSIONS AND RELEVANCE
Among overweight or obese adults, orlistat, lorcaserin, naltrexone-bupropion, phentermine-topiramate, and liraglutide, compared with placebo, were each associated with achieving at least 5% weight loss at 52 weeks. Phentermine-topiramate and liraglutide were associated with the highest odds of achieving at least 5% weight loss.
Topics: Anti-Obesity Agents; Bayes Theorem; Benzazepines; Drug Combinations; Female; Fructose; Humans; Lactones; Liraglutide; Male; Middle Aged; Naltrexone; Obesity; Orlistat; Phentermine; Randomized Controlled Trials as Topic; Topiramate; Weight Loss
PubMed: 27299618
DOI: 10.1001/jama.2016.7602 -
Current Obesity Reports Mar 2021As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of... (Review)
Review
PURPOSE OF REVIEW
As a chronic and relapsing disease, obesity impairs metabolism and causes cardiovascular diseases. Although behavioral modification is important for the treatment of obesity, it is difficult to achieve an ideal weight or sustain the process of long-term weight loss. Therefore, the obesity control guidelines strongly recommend lifestyle interventions along with medical treatment for patients who are overweight. There is sufficient evidence supporting that pharmacotherapy in combination with behavior-based interventions can result in significant weight loss and improved cardiometabolism.
RECENT FINDINGS
Recent meta-analyses of new anti-obesity drugs and their weight-loss efficacy have shown that the overall placebo-subtracted weight reduction (%) for at least 12 months ranged from 2.9 to 6.8% for the following drugs: phentermine/topiramate (6.8%), liraglutide (5.4%), naltrexone/bupropion (4.0%), orlistat (2.9%), and lorcaserin (3.1%). However, very recently, on February 13, 2020, the US Food and Drug Administration (FDA) ordered the withdrawal of lorcaserin from markets, as a clinical trial to assess drug safety showed an increased risk of cancer. Currently, the anti-obesity medications that have been approved by the FDA for chronic weight management are orlistat, phentermine/topiramate, naltrexone/bupropion, and liraglutide. However, they are costly and may have adverse effects in some individuals. Therefore, drug therapy should be initiated in obese individuals after weighing its benefits and risks. One of the strategies for long-term obesity control is that anti-obesity medications should be tailored for specific patients depending on their chronic conditions, comorbidities, and preferences.
Topics: Animals; Anti-Obesity Agents; Benzazepines; Bupropion; Humans; Liraglutide; Naltrexone; Obesity; Orlistat; Overweight; Phentermine; Topiramate; United States; United States Food and Drug Administration; Weight Loss
PubMed: 33410104
DOI: 10.1007/s13679-020-00422-w -
Diabetes & Metabolism Journal Dec 2020Obesity is among the leading causes of morbidity and mortality worldwide and its prevalence continues to increase globally. Because obesity is a chronic, complex, and... (Review)
Review
Obesity is among the leading causes of morbidity and mortality worldwide and its prevalence continues to increase globally. Because obesity is a chronic, complex, and heterogeneous disease influenced by genetic, developmental, biological, and environmental factors, it is necessary to approach obesity with an integrated and comprehensive treatment strategy. As it is difficult to achieve and sustain successful long-term weight loss in most patients with obesity through lifestyle modifications (e.g., diet, exercise, and behavioral therapy), pharmacological approaches to the treatment of obesity should be considered as an adjunct therapy. Currently, four drugs (orlistat, naltrexone extended-release [ER]/bupropion ER, phentermine/topiramate controlled-release, and liraglutide) can be used long-term (>12 weeks) to promote weight loss by suppressing appetite or decreasing fat absorption. Pharmacotherapy for obesity should be conducted according to a proper assessment of the clinical evidence and customized to individual patients considering the characteristics of each drug and comorbidities associated with obesity. In this review, we discuss the mechanisms of action, efficacy, and safety of these available long-term anti-obesity drugs and introduce other potential agents under investigation. Furthermore, we discuss the need for research on personalized obesity medicine.
Topics: Anti-Obesity Agents; Benzazepines; Humans; Orlistat; Phentermine; Weight Loss
PubMed: 33389955
DOI: 10.4093/dmj.2020.0258 -
Journal of Experimental & Clinical... Jan 2023Sorafenib resistance is a key impediment to successful treatment of patients with advanced hepatocellular carcinoma (HCC) and recent studies have reported reversal of...
BACKGROUND
Sorafenib resistance is a key impediment to successful treatment of patients with advanced hepatocellular carcinoma (HCC) and recent studies have reported reversal of drug resistance by targeting ferroptosis. The present study aimed to explore the association of fatty acid synthase (FASN) with sorafenib resistance via regulation of ferroptosis and provide a novel treatment strategy to overcome the sorafenib resistance of HCC patients.
METHODS
Intracellular levels of lipid peroxides, glutathione, malondialdehyde, and Fe were measured as indicators of ferroptosis status. Biological information analyses, immunofluorescence assays, western blot assays, and co-immunoprecipitation analyses were conducted to elucidate the functions of FASN in HCC. Both in vitro and in vivo studies were conducted to examine the antitumor effects of the combination of orlistat and sorafenib and CalcuSyn software was used to calculate the combination index.
RESULTS
Solute carrier family 7 member 11 (SLC7A11) was found to play an important role in mediating sorafenib resistance. The up-regulation of FASN antagonize of SLC7A11-mediated ferroptosis and thereby promoted sorafenib resistance. Mechanistically, FASN enhanced sorafenib-induced ferroptosis resistance by binding to hypoxia-inducible factor 1-alpha (HIF1α), promoting HIF1α nuclear translocation, inhibiting ubiquitination and proteasomal degradation of HIF1α, and subsequently enhancing transcription of SLC7A11. Orlistat, an inhibitor of FASN, with sorafenib had significant synergistic antitumor effects and reversed sorafenib resistance both in vitro and in vivo.
CONCLUSION
Targeting the FASN/HIF1α/SLC7A11 pathway resensitized HCC cells to sorafenib. The combination of orlistat and sorafenib had superior synergistic antitumor effects in sorafenib-resistant HCC cells.
Topics: Humans; Carcinoma, Hepatocellular; Cell Line, Tumor; Drug Resistance, Neoplasm; Fatty Acid Synthases; Ferroptosis; Liver Neoplasms; Orlistat; Sorafenib
PubMed: 36604718
DOI: 10.1186/s13046-022-02567-z -
Pharmacotherapy Mar 2000Orlistat, a weight-loss agent with a novel mechanism of action, recently was approved by the Food and Drug Administration for the treatment of obesity. It inhibits... (Review)
Review
Orlistat, a weight-loss agent with a novel mechanism of action, recently was approved by the Food and Drug Administration for the treatment of obesity. It inhibits gastric and pancreatic lipases in the lumen of the gastrointestinal tract to decrease systemic absorption of dietary fat. In several trials lasting up to 2 years, orlistat was more effective than diet alone for weight reduction and maintenance of lost weight. Orlistat treatment also results in modest improvements in total cholesterol, low-density lipoprotein, blood pressure, and fasting glucose and insulin concentrations. The major adverse effects are gastrointestinal, usually occur early in therapy, and tend to decrease with continued treatment. Because orlistat may decrease the absorption of fat-soluble vitamins, a standard multiple-vitamin supplement is recommended daily during therapy to prevent abnormalities in vitamin serum concentrations. The potential for severe gastrointestinal discomfort and the modest degree of weight loss may limit the agent's clinical utility. Its long-term safety and effectiveness for weight maintenance, cost-effectiveness of treatment, and overall reduction in obesity-related morbidity and mortality remain to be determined.
Topics: Anti-Obesity Agents; Enzyme Inhibitors; Humans; Lactones; Lipase; Obesity; Orlistat; Randomized Controlled Trials as Topic
PubMed: 10730683
DOI: 10.1592/phco.20.4.270.34882 -
Signal Transduction and Targeted Therapy May 2023Continuous de novo fatty acid synthesis is required for the biosynthetic demands of tumor. FBXW7 is a highly mutated gene in CRC, but its biological functions in cancer...
Continuous de novo fatty acid synthesis is required for the biosynthetic demands of tumor. FBXW7 is a highly mutated gene in CRC, but its biological functions in cancer are not fully characterized. Here, we report that FBXW7β, a FBXW7 isoform located in the cytoplasm and frequently mutated in CRC, is an E3 ligase of fatty acid synthase (FASN). Cancer-specific FBXW7β mutations that could not degrade FASN can lead to sustained lipogenesis in CRC. COP9 signalosome subunit 6 (CSN6), an oncogenic marker of CRC, increases lipogenesis via interacting with and stabilizing FASN. Mechanistic studies show that CSN6 associates with both FBXW7β and FASN, and antagonizes FBXW7β's activity by enhancing FBXW7β autoubiquitination and degradation, which in turn prevents FBXW7β-mediated FASN ubiquitination and degradation, thereby regulating lipogenesis positively. Both CSN6 and FASN are positively correlated in CRC, and CSN6-FASN axis, regulated by EGF, is responsible for poor prognosis of CRC. The EGF-CSN6-FASN axis promotes tumor growth and implies a treatment strategy of combination of orlistat and cetuximab. Patient-derived xenograft experiments prove the effectiveness of employing orlistat and cetuximab combination in suppressing tumor growth for CSN6/FASN-high CRC. Thus, CSN6-FASN axis reprograms lipogenesis to promote tumor growth and is a target for cancer intervening strategy in CRC.
Topics: Humans; Cetuximab; Colorectal Neoplasms; Epidermal Growth Factor; F-Box-WD Repeat-Containing Protein 7; Fatty Acid Synthase, Type I; Fatty Acid Synthases; Lipogenesis; Orlistat
PubMed: 37202390
DOI: 10.1038/s41392-023-01405-8 -
Journal of Advanced Research Mar 2022The prognosis for cervical cancer (CC) patients with lymph node metastasis (LNM) is extremely poor. Lipid droplets (LDs) have a pivotal role in promoting tumor...
INTRODUCTION
The prognosis for cervical cancer (CC) patients with lymph node metastasis (LNM) is extremely poor. Lipid droplets (LDs) have a pivotal role in promoting tumor metastasis. The crosstalk mechanism between LDs and LNM modulated in CC remains largely unknown.
OBJECTIVES
This study aimed to construct a miRNA-dependent progonostic model for CC patients and investigate whether miR-532-5p has a biological impact on LNM by regualting LDs accumulation.
METHODS
LASSO-Cox regression was applied to establish a prognostic prediction model. miR-532-5p had the lowest P-value in RNA expression (P < 0.001) and prognostic prediction (P < 0.0001) and was selected for further study. The functional role of the prognostic miR-532-5p-correlated competing endogenous RNA (ceRNA) network was investigated to clarify the crosstalk between LDs and LNM. The underlying mechanism was determined using site-directed mutagenesis, dual luciferase reporter assays, RNA immunoprecipitation assays, and rescue experiments. A xenograft LNM model was established to evaluate the effect of miR-532-5p and orlistat combination therapy on tumor growth and LNM.
RESULTS
A novel 5-miRNAs prognostic signature was constructed to better predict the prognosis of CC patient. Further study demonstrated that miR-532-5p inhibited epithelial-mesenchymal transition and lymphangiogenesis by regulating LDs accumulation. Interestingly, we also found that LDs accumulation promoted cell metastasis in vitro. Mechanistically, we demonstrated a miR-532-5p-correlated ceRNA network in which LINC01410 was bound directly to miR-532-5p and effectively functioned as miR-532-5p sponge to disinhibit its target gene-fatty acid synthase (). Combined therapy with miR-532-5p and FASN inhibitor-orlistat further inhibited tumor growth and LNM in vivo.
CONCLUSION
Our findings highlight a LD accumulation-dependent mechanism of miR-532-5p-modulated LNM and support treatment with miR-532-5p/orlistat as novel strategy for treating patients with LNM in CC.
Topics: Cell Line, Tumor; Cell Proliferation; Female; Humans; Lipid Droplets; Lymphatic Metastasis; MicroRNAs; Orlistat; Prognosis; Uterine Cervical Neoplasms
PubMed: 35499057
DOI: 10.1016/j.jare.2021.09.009