Growth differentiation factor 15 is not modified after weight loss induced by liraglutide in South Asians and Europids with type 2 diabetes mellitus.

Glucagon-like peptide-1 receptor (GLP-1R) agonists induce weight loss in patients with type 2 diabetes mellitus (T2DM), but the underlying mechanism is unclear. Recently, the mechanism by which metformin induces weight loss could be explained by an increase in growth differentiation factor 15 (GDF15), which suppresses appetite. Therefore, we aimed to investigate whether the GLP-1R agonist liraglutide modifies plasma GDF15 levels in patients with T2DM. GDF15 levels were measured in plasma samples obtained from Dutch Europids and Dutch South Asians with T2DM before and after 26 weeks of treatment with daily liraglutide (n = 44) or placebo (n = 50) added to standard care. At baseline, circulating GDF15 levels did not differ between South Asians and Europids with T2DM. Treatment with liraglutide, compared to placebo, decreased body weight, but did not modify plasma GDF15 levels in all patients, or when data were split by ethnicity. Also, the change in plasma GDF15 levels after treatment with liraglutide did not correlate with changes in body weight or HbA1c levels. In addition, the dose of metformin used did not correlate with baseline plasma GDF15 levels. Compared to placebo, liraglutide treatment for 26 weeks does not modify plasma GDF15 levels in Dutch Europid or South Asian patients with T2DM. Thus, the weight loss induced by liraglutide is likely explained by other mechanisms beyond the GDF15 pathway. HIGHLIGHTS: What is the central question of this study? Growth differentiation factor 15 (GDF15) suppresses appetite and is increased by metformin: does the GLP-1R agonist liraglutide modify plasma GDF15 levels in patients with type 2 diabetes mellitus (T2DM)? What is the main finding and its importance? Plasma GDF15 levels did not differ between South Asians and Europids with T2DM and were not modified by 26 weeks of liraglutide in either ethnicity. Moreover, there was no correlation between the changes in plasma GDF15 levels and dosage of metformin administered, changes in body weight or HbA1c levels. The appetite-suppressing effect of liraglutide is likely exerted via pathways other than GDF15.

GLP-1 receptor agonists for the treatment of obesity: Role as a promising approach.

Obesity is a complex disease characterized by excessive fat accumulation which is caused by genetic, environmental and other factors. In recent years, there has been an increase in the morbidity, disability rate,and mortality due to obesity, making it great threat to people's health and lives, and increasing public health care expenses. Evidence from previous studies show that weight loss can significantly reduce the risk of obesity-related complications and chronic diseases. Diet control, moderate exercise, behavior modification programs, bariatric surgery and prescription drug treatment are the major interventions used to help people lose weight. Among them, anti-obesity drugs have high compliance rates and cause noticeable short-term effects in reducing obese levels. However, given the safety or effectiveness concerns of anti-obesity drugs, many of the currently used drugs have limited clinical use. Glucagon-like peptide-1 receptor (GLP-1R) agonists are a group of drugs that targets incretin hormone action, and its receptors are widely distributed in nerves, islets, heart, lung, skin, and other organs. Several animal experiments and clinical trials have demonstrated that GLP-1R agonists are more effective in treating or preventing obesity. Therefore, GLP-1R agonists are promising agents for the treatment of obese individuals. This review describes evidence from previous research on the effects of GLP-1R agonists on obesity. We anticipate that this review will generate data that will help biomedical researchers or clinical workers develop obesity treatments based on GLP-1R agonists.

Impact of anti-obesity medication initiation and duration on weight loss in a comprehensive weight loss programme.

OBJECTIVE: This retrospective study aimed to evaluate the impact of anti-obesity medication (AOM) initiation, usage and duration on weight loss in a 72-week precision obesity programme. The type of AOM, diet and exercise plan was chosen based upon an individual's biological and psychosocial needs. The 72-week study duration allowed for a fair investigation of the downstream impact of delayed versus early AOM initiation. METHODS: Participants, aged ≥18 years with body mass index ≥30 kg m-2, enrolled from 1 March 2015 to 1 April 2017, were included. Subgroups were assigned by AOM usage (users versus non-users, early [before 8 weeks] versus delayed [after 8 weeks] AOM initiation and short [<6 months] versus long [≥6 months] AOM duration). Primary endpoints included change in baseline weight at 72 weeks and proportions achieving ≥5%, ≥10% and ≥15% weight loss. Outcomes were compared between subgroups. RESULTS: Mean age and body mass index (N = 129) were 45.0 ± 14.0 years and 37.0 ± 6.0 kg m-2, respectively; 67% were female. At week 72, AOM users (N = 71) achieved significantly greater mean percentage reduction in baseline weight than non-users (N = 58). On average, baseline weight decreased by 14.04 ± 6.2% in users versus 10.9 ± 6.8% in non-users (P = 0.008); 84% and 94% of non-user and AOM users lost >5% weight loss (P = 0.006). A higher proportion of users lost ≥15% of weight (45.1% vs. 19.0%; P < 0.001). Mean percentage reduction in weight was greater for early versus delayed starters (-17.60 ± 5.3% vs. -13.95 ± 5.5%; P = 0.024), and longer AOM usage trended towards increased weight loss. CONCLUSION: Early initiation of AOM may enhance weight loss.

Exposure-response model for sibutramine and placebo: suggestion for application to long-term weight-control drug development.

No wholly successful weight-control drugs have been developed to date, despite the tremendous demand. We present an exposure-response model of sibutramine mesylate that can be applied during clinical development of other weight-control drugs. Additionally, we provide a model-based evaluation of sibutramine efficacy. Data from a double-blind, randomized, placebo-controlled, multicenter study were used (N=120). Subjects in the treatment arm were initially given 8.37 mg sibutramine base daily, and those who lost <2 kg after 4 weeks' treatment were escalated to 12.55 mg. The duration of treatment was 24 weeks. Drug concentration and body weight were measured predose and at 4 weeks, 8 weeks, and 24 weeks after treatment initiation. Exposure and response to sibutramine, including the placebo effect, were modeled using NONMEM 7.2. An asymptotic model approaching the final body weight was chosen to describe the time course of weight loss. Extent of weight loss was described successfully using a sigmoidal exposure-response relationship of the drug with a constant placebo effect in each individual. The placebo effect was influenced by subjects' sex and baseline body mass index. Maximal weight loss was predicted to occur around 1 year after treatment initiation. The difference in mean weight loss between the sibutramine (daily 12.55 mg) and placebo groups was predicted to be 4.5% in a simulation of 1 year of treatment, with considerable overlap of prediction intervals. Our exposure-response model, which included the placebo effect, is the first example of a quantitative model that can be used to predict the efficacy of weight-control drugs. Similar approaches can help decision-making during clinical development of novel weight-loss drugs.

Chinese slimming capsules containing sibutramine sold over the Internet: a case series.

BACKGROUND: In recent years, the market for dietary supplements has grown. International products are readily available for purchase over the Internet. We report 17 cases of poisoning with a single product, said to be of purely herbal origin, that was bought over the Internet. A complete declaration of the ingredients was not available. METHODS: We performed a retrospective study of cases of poisoning documented by the Göttingen and Freiburg poison information centers from 2005 to 2008. In 4 cases, we were able to perform toxicological analyses of leftover capsules and urine samples. RESULTS: The manifestations of poisoning in the 17 documented cases included malaise, tachycardia, headache, agitation, arterial hypertension, nausea, vomiting, dyspnea, insomnia, left-sided chest pressure, elevated temperature, and, in two cases, psychosis after the substance was combined with atomoxetine and methylphenidate and with citalopram, olanzapine, and chlorprothixene. The frequency of cases rose markedly in the last year of the study. The toxicological analyses of all samples studied revealed sibutramine. The dose in each capsule was nearly twice the maximum daily dose sibutramine in the medication containing this substance that is licensed for use in Germany. CONCLUSIONS: Products available without a prescription whose contents are claimed to be purely herbal may nonetheless contain synthetic substances in concentrations far above the therapeutic range and may be a cause of poisoning. When taking the history of a patient possibly suffering from an intoxication, the physician should ask specifically about drugs, dietary supplements, and so-called lifestyle products that were obtained without a prescription. It would be desirable for the contents of all such products to be declared, as required by law, so that their suitability for the market can be checked.