Drug treatment of obesity in cardiovascular disease

Antithrombotic therapy in obesity

Clinical management of obese subjects to reduce their risk of suffering cardiovascular events is complex. Obese patients typically require preventive strategies, life-style modifications, and multi-drug therapy to address obesity-induced co-morbidities. Data regarding the effects of excess weight on the pharmacokinetics of most drugs is scarce as these individuals are often excluded from clinical trials. However, the physiological alterations observed in obese patients and their lower response to some antiplatelet agents and anticoagulants have suggested that dosage regimes need to be adjusted for these subjects. In this review we will briefly discuss platelet alterations that can contributeto increased thrombotic risk, analyse existing data regarding the effects of obesity on drug pharmacokinetics focusing on antiplatelet agents and anticoagulants, and we will describe the beneficial effects of weight loss on thrombosis.

Effect of short-term consumption bitter apricot seeds on the body composition in healthy population

The distribution of fat in different areas of the body is important since accumulation of fat within the abdominal cavity represents a much more severe cardiovascular risk than accumulation in subcutaneous adipose tissues. Apricot seeds contain a wide variety of bioactive compounds and that consumption can decrease blood pressure and total blood cholesterol levels, fight oxidative stress and maintain body weight. The aim of the study was to analyse body composition: body fat mass (BFM), fat free mass (FFM), skeletal muscle mass (SMM), body fat percentage (%BFM), visceral fat area (VFA), total body water (TBW) - intracellular water (ICW) and extracellular water (ECW) and to evaluate the changes that occur after 6-weeks consumption of bitter apricot seeds. The study group finally consisted of 34 healthy adults volunteers (21 females and 13 males). Volunteers were recruited from the general population of Slovakia. Respondents were 23 - 65 years old, where the average age of women was 40.65 ±11.31 years and the average age of men was 36.91 ±9.98 years. All participants were asked to consume 60 mg.kg-1 of body weight of bitter apricot seeds daily during 6 weeks. Body composition was diagnosed by multi-frequency bioelectrical impedance analysis (MFBIA) by InBody 720 (Biospace Co., Korea), which measures the total impedance at frequencies of 1, 5, 50, 100, 500, 1000 kHz. At baseline mean body weight was 85.78 ±14.66 and 62.84 ±12.19 kg in the male and female participants, respectively. After 6 weeks of consumation we observed non-significant decreasing of mean body weight. The mean BFM was 19.25 ±8.81 kg in the male group and 19.47 ±7.21 kg in the female group. After six weeks, BFM decreased non-significantly (on average 0.5 kg) in both groups. The mean FFM at baseline was 43.37 ±5.98 and 66.54 ±7.98 kg in the female and male participants, respectively. The statistical analysis confirmed that the increase of FFM (43.37 ±5.98 kg to 43.56 ±5.80 kg) in the female were statistically significant (p <0.05). VFA was greater in the men (82.04 ±39.82 cm2 at baseline and 78.65 ±39.79 cm2 after 6 weeks) comparison to women (79.82 ±29.03 cm2 at baseline and 78.29 ±29.90 cm2 after 6 weeks). The mean of TBW in males before the start of study was 48.78 ±5.77 kg and 47.88 ±5.57 kg after 6 weeks of consumption. The results of study show the small weight loss in the both group. Therefore, the results from this study indicate that daily consumption of bitter apricot seeds produce measurable health benefits, but further studies are also required.

Post-marketing withdrawal of anti-obesity medicinal products because of adverse drug reactions: a systematic review

BACKGROUND

We identified anti-obesity medications withdrawn since 1950 because of adverse drug reactions after regulatory approval, and examined the evidence used to support such withdrawals, investigated the mechanisms of the adverse reactions, and explored the trends over time.

METHODS

We conducted searches in PubMed, the World Health Organization database of drugs, the websites of drug regulatory authorities, and selected full texts, and we hand searched references in retrieved documents. We included anti-obesity medications that were withdrawn between 1950 and December 2015 and assessed the levels of evidence used for making withdrawal decisions using the Oxford Centre for Evidence-Based Medicine criteria.

RESULTS

We identified 25 anti-obesity medications withdrawn between 1964 and 2009; 23 of these were centrally acting, via monoamine neurotransmitters. Case reports were cited as evidence for withdrawal in 80% of instances. Psychiatric disturbances, cardiotoxicity (mainly attributable to re-uptake inhibitors), and drug abuse or dependence (mainly attributable to neurotransmitter releasing agents) together accounted for 83% of withdrawals. Deaths were reportedly associated with seven products (28%). In almost half of the cases, the withdrawals occurred within 2 years of the first report of an adverse reaction.

CONCLUSIONS

Most of the drugs that affect monoamine neurotransmitters licensed for the treatment of obesity over the past 65 years have been withdrawn because of adverse reactions. The reasons for withdrawal raise concerns about the wisdom of using pharmacological agents that target monoamine neurotransmitters in managing obesity. Greater transparency in the assessment of harms from anti-obesity medications is therefore warranted.

Evolution of pharmacological obesity treatments: focus on adverse side-effect profiles

Pharmacotherapy directed toward reducing body weight may provide benefits for both curbing obesity and lowering the risk of obesity-associated comorbidities; however, many weight loss medications have been withdrawn from the market because of serious adverse effects. Examples include pulmonary hypertension (aminorex), cardiovascular toxicity, e.g. flenfluramine-induced valvopathy, stroke [phenylpropanolamine (PPA)], excess non-fatal cardiovascular events (sibutramine), and neuro-psychiatric issues (rimonabant; approved in Europe, but not in the USA). This negative experience has helped mould the current drug development and approval process for new anti-obesity drugs. Differences between the US Food and Drug Administration (FDA) and the European Medicines Agency, however, in perceptions of risk-benefit considerations for individual drugs have resulted in discrepancies in approval and/or withdrawal of weight-reducing medications. Thus, two drugs recently approved by the FDA, i.e. lorcaserin and phentermine + topiramate extended release, are not available in Europe. In contrast, naltrexone sustained release (SR)/bupropion SR received FDA approval, and liraglutide 3.0 mg was recently approved in both the USA and Europe. Regulatory strategies adopted by the FDA to manage the potential for uncommon but potentially serious post-marketing toxicity include: (i) risk evaluation and mitigation strategy programmes; (ii) stipulating post-marketing safety trials; (iii) considering responder rates and limiting cumulative exposure by discontinuation if weight loss is not attained within a reasonable timeframe; and (iv) requiring large cardiovascular outcome trials before or after approval. We chronicle the adverse effects of anti-obesity pharmacotherapy and consider how the history of high-profile toxicity issues has shaped the current regulatory landscape for new and future weight-reducing drugs.

Role of adipocytes in hypertension

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

The Effect of Cumin cyminum L. Plus Lime Administration on Weight Loss and Metabolic Status in Overweight Subjects: A Randomized Double-Blind Placebo-Controlled Clinical Trial

Background

Limited data are available regarding the effects of combined administration of Cumin cyminum L. and lime on weight loss and metabolic profiles among subjects with overweight subjects.

Objectives

The current study aimed to assess the effects of combined administration of Cumin cyminum L. and lime on weight loss and metabolic profiles among subjects with overweight.

Patients and Methods

This randomized double-blind placebo-controlled clinical trial was conducted on 72 subjects with overweight, aged 18 - 50 years old. Participants were randomly divided into three groups: Group A received high-dose Cumin cyminum L. and lime capsules (75 mg each, n = 24), group B low-dose Cumin cyminum L. and lime capsules (25 mg each, n = 24) and group C placebos (n = 24) twice daily for eight weeks.

Results

After eight weeks of intervention, compared with low-dose C. cyminum L. plus lime and placebo, taking high-dose C. cyminum L. plus lime resulted in significant weight loss (in the high-dose group: -2.1 ± 1.7 vs. in the low-dose group: -1.2 ± 1.5 and in the placebo group: + 0.2 ± 1.3 kg, respectively; P < 0.001) and body mass index (-0.8 ± 0.6 vs. -0.5 ± 0.5 and +0.1 ± 0.5 kg/m², respectively; P < 0.001). In addition, administration of high-dose C. cyminum L. plus lime compared with low-dose C. cyminum L. plus lime and placebo, led to a significant reduction in fasting plasma glucose (FPG) (P < 0.001) and a significant rise in quantitative insulin sensitivity check index (QUICKI) (+ 0.02 ± 0.02 vs. + 0.01 ± 0.02 and 0.01 ± 0.01, respectively; P = 0.01). Moreover, a significant decrease in serum triglycerides (-14.1 ± 56.2 vs. +13.9 ± 36.8 and + 10.6 ± 25.1 mg/dL; respectively; P = 0.03), total-cholesterol (-18.4 ± 28.6 vs. +8.6 ± 28.5 and -1.0 ± 24.8 mg/dL; respectively; P = 0.004) and low density lipoproteins- (LDL)-cholesterol levels (-11.8 ± 20.7 vs. +6.5 ± 23.2 and -2.9 ± 20.4 mg/dL, respectively; P = 0.01) was observed following the consumption of high-dose C. cyminum L. plus lime compared with low-dose C. cyminum L. plus lime and placebo.

Conclusions

Results of the current study indicated that taking high-dose C. cyminum L. plus lime for eight weeks among subjects with overweight had beneficial effects on weight, BMI, FPG, QUICKI, triglycerides, total-cholesterol and LDL-cholesterol levels.

Managing cardiovascular risk in overweight children and adolescents

The scientific, medical, and lay communities are currently confronted with a serious medical and public health problem related to the marked non-remitting worldwide epidemic of obesity. This ever-increasing prevalence of obesity is accompanied by a host of inherently associated co-morbidities. As a result, obesity is fast becoming the major cause of premature death in the developed world. As pediatric and adult cardiologists, we have seen a dramatic increase in office referrals of overweight and obese children and adolescents, who already have obesity-related degenerative disease processes such as hypertension, dyslipidemia, the metabolic syndrome, and type 2 diabetes mellitus, as well as manifestations of early preclinical atherosclerotic cardiovascular disease, not previously observed in this age group. This article presents a review of the literature and recent scientific statements and recommendations issued by the American Heart Association (AHA) and the American Academy of Pediatrics (AAP) regarding the metabolic abnormalities associated with obesity, including newer identification and treatment strategies for obesity, dyslipidemia, and early subclinical coronary artery disease seen in high-risk children and adolescents.

Lipoprotein subfractions in metabolic syndrome and obesity: clinical significance and therapeutic approaches

Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk.

Lipoprotein subfractions in metabolic syndrome and obesity: clinical significance and therapeutic approaches

Small, dense low density lipoprotein (sdLDL) represents an emerging cardiovascular risk factor, since these particles can be associated with cardiovascular disease (CVD) independently of established risk factors, including plasma lipids. Obese subjects frequently have atherogenic dyslipidaemia, including elevated sdLDL levels, in addition to elevated triglycerides (TG), very low density lipoprotein (VLDL) and apolipoprotein-B, as well as decreased high density lipoprotein cholesterol (HDL-C) levels. Obesity-related co-morbidities, such as metabolic syndrome (MetS) are also characterized by dyslipidaemia. Therefore, agents that favourably modulate LDL subclasses may be of clinical value in these subjects. Statins are the lipid-lowering drug of choice. Also, anti-obesity and lipid lowering drugs other than statins could be useful in these patients. However, the effects of anti-obesity drugs on CVD risk factors remain unclear. We review the clinical significance of sdLDL in being overweight and obesity, as well as the efficacy of anti-obesity drugs on LDL subfractions in these individuals; a short comment on HDL subclasses is also included. Our literature search was based on PubMed and Scopus listings. Further research is required to fully explore both the significance of sdLDL and the efficacy of anti-obesity drugs on LDL subfractions in being overweight, obesity and MetS. Improving the lipoprotein profile in these patients may represent an efficient approach for reducing cardiovascular risk.

α-Lipoic acid attenuates cardiac fibrosis in Otsuka Long-Evans Tokushima Fatty rats

Background

Hyperglycemia leads to cardiac oxidative stress and an imbalance in glucose homeostasis. Diabetic cardiomyopathy is characterised by cardiac hypertrophy and fibrosis. However, the underlying mechanisms of diabetic cardiomyopathy are not fully understood. This study aimed to investigate the effects of alpha-lipoic acid (ALA) on cardiac energy metabolism, antioxidant effect, and fibrosis in the hearts of Otsuka Long-Evans Tokushima fatty (OLETF) rats.

Methods

Animals were separated into non-diabetic Long-Evans Tokushima Otsuka (LETO) rats and diabetes-prone OLETF rats with or without ALA (200 mg/kg/day) administration for 16 weeks. Diabetic cardiomyopathy was assessed by staining with Sirius Red. The effect of ALA on AMPK signalling, antioxidant enzymes, and fibrosis-related genes in the heart of OLETF rats were performed by Western blot analysis or immunohistochemistry.

Results

Western blot analysis showed that cardiac adenosine monophosphate-activated kinase (AMPK) signalling was lower in OLETF rats than in LETO rats, and that ALA treatment increased the signalling in OLETF rats. Furthermore, the low antioxidant activity in OLETF rats was increased by ALA treatment. In addition to increased Sirius red staining of collagen deposits, transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) were expressed at higher levels in OLETF rat hearts than in LETO rat hearts, and the levels of these factors were decreased by ALA.

Conclusions

ALA enhances AMPK signalling, antioxidant, and antifibrogenic effect. Theses findings suggest that ALA may have beneficial effects in the treatment of diabetic cardiomyopathy.

Effect of obesity reduction on preservation of heart function and attenuation of left ventricular remodeling, oxidative stress and inflammation in obese mice

BACKGROUND

Obesity is an important cardiovascular risk factor. This study tested the effect of obesity reduction on preserving left ventricular ejection fraction (LVEF) and attenuating inflammation, oxidative stress and LV remodeling in obese mice.

METHODS AND RESULTS

Eight-week-old C57BL/6 J mice (n=24) were equally divided into control (fed a control diet for 22 weeks), obesity (high-fat diet, 22 weeks), and obese reduction (OR) (high-fat diet, 14 weeks; then control diet, 8 weeks). Animals were sacrificed at post 22-week high-fat diet and the LV myocardium collected. Heart weight, body weight, abdominal-fat weight, total cholesterol level and fasting blood glucose were higher in obesity than in control and OR (all p<0.001). Inflammation measured by mRNA expressions of IL-6, MMP-9, PAI-1 and leptin and protein expression of NF-κB was higher, whereas anti-inflammation measured by mRNA expressions of adiponectin and INF-γ was lower in obesity than in control and OR (all p<0.003). Oxidative protein expressions of NOX-1, NOX-2 and oxidized protein were higher, whereas expression of anti-oxidant markers HO-1 and NQO-1 were lower (all p<0.01); and apoptosis measured by Bax and caspase 3 was higher, whereas anti-apoptotic Bcl-2 was lower in obesity as compared with control and OR (all p<0.001). The expressions of fibrotic markers phosphorylated Smad3 and TGF-β were higher, whereas expression of anti-fibrotic phosphorylated Smad1/5 and BMP-2 were lower (all p<0.02); and LVEF was lower, whereas the LV remodeling was higher in obesity than in control and OR (all p<0.001).

CONCLUSION

Impaired LVEF, enhanced LV remodeling, inflammation, fibrosis, oxidative stress and apoptosis were reversed by reduction in mouse obesity.