Impact of statin therapy on plasma leptin concentrations: a systematic review and meta-analysis of randomized placebo-controlled trials

The effect of hydrophilic statins on adiponectin, leptin, visfatin, and vaspin levels in streptozocin-induced diabetic rats

Statins may affect glucose metabolism through adipokines. The aim of this study was to measure the effects of hydrophilic statins on the levels of several adipokines in diabetic rats. Wistar albino rats were divided into four groups: healthy control, untreated diabetic, diabetic treated with pravastatin, and diabetic treated with rosuvastatin. Diabetes was induced by intraperitoneal injection of STZ. Thereafter, 20 mg/kg/day doses of either pravastatin or rosuvastatin were administered to the treated diabetic rats for 8 weeks. At the end of the experiment, the body weights, fasting blood glucose levels, serum insulin levels, and insulin resistance, as well as the serum adiponectin, leptin, visfatin, and vaspin levels, were measured. Fasting blood glucose and insulin resistance levels were significantly higher, whereas insulin levels and body weight were significantly lower in the untreated diabetic group than in the control group. Diabetes caused significant decreases in adiponectin, leptin, and vaspin levels but a significant increase in visfatin levels. Pravastatin treatment significantly increased body weight and decreased fasting blood glucose levels, whereas rosuvastatin decreased body weight but did not affect fasting blood glucose levels. Pravastatin caused significant increases in both adiponectin and vaspin levels. However, rosuvastatin did not affect the adiponectin level but caused a significant decrease in the vaspin levels. Both pravastatin and rosuvastatin treatments decreased the leptin and visfatin levels. In conclusion, pravastatin is more effective at improving fasting blood glucose levels and body weight in diabetic rats, probably by increasing adiponectin and vaspin levels.

Recurrent depression predicts high leptin concentrations in patients with coronary artery disease over an 18-months follow-up period: Findings from the prospective multicenter randomized controlled SPIRR-CAD Trial

BACKGROUND

Leptin, an adipokine suspected to play a role in coronary artery disease (CAD), may also be associated with deteriorated mental health. We investigated the prospective impact of recurrent depressed mood (RDM) on heightened plasma leptin levels in CAD patients.

METHODS

Derived from the randomized SPIRR-CAD trial, plasma leptin were measured by the Human Leptin DuoSet ELISA at baseline in 539 patients (including 115 (21.3 %) women and 424 (78.7 %) men) and in 373 participants after 18-months follow up (T3). RDM was based on the clinical course from baseline to follow-up assessed by the Hamilton Depression Rating Scale (HAMD). Multivariate binary logistic regression models identified predictors for heightened leptin at T3.

RESULTS

At baseline, highest leptin level (3rd tertile) was associated with type 2 diabetes (p = 0.009), heart failure symptoms (NYHA III) (p < 0.001), female sex and BMI ≥30 (p < 0.001) but not with age and depression. At study endpoint (T3), RDM was associated with a substantially increased risk of experiencing the highest plasma leptin level (OR 2.92 (95 % CI 1.27-6.75)) followed by increased NT-proBNP (the most prominent indicator of CHF) with an OR of 2.73 (1.22-6.11) - both after adjustment for concurrent factors including weight gain (diff BMI T3-T1) over the study period - the latter accounting for an OR of 1.41 (1.17-1.70).

LIMITATIONS

Findings are limited to people of Caucasian ancestry which prevents being generalized to other ethnicities. Although relying upon a prospective design, reverse causality cannot be excluded but is unlikely.

CONCLUSIONS

In CAD patients, RDM is a significant predictor of heightened leptin -a finding opening room for a new pathway of the psychobiological underpinning of depression on CAD risk.

Association of Cardiopulmonary Exercise Capacity and Adipokines in the General Population

Adipokines and cardiorespiratory fitness (CRF) are associated with the (patho)physiology of cardiometabolic diseases. Whether CRF and adipokines are related is unclear. We investigated associations of CRF with leptin, adiponectin, chemerin, resistin and vaspin. Data from the population-based Study of Health in Pomerania was used (n=1,479; median age 49 years; 51% women). Cardiopulmonary exercise testing was used to measure CRF. Circulating adipokine concentrations were measured by enzyme-linked immunosorbent assay. The association between CRF and adipokines was assessed using multivariable sex-specific quantile regression models. Higher maximum oxygen uptake was significantly associated with lower leptin (men:-0.11 ng/ml; 95%-confidence interval [CI]:-0.18 to-0.03 ng/ml; p<0.005; women:-0.17 ng/ml; 95%-CI:-0.33 to-0.02 ng/ml; p<0.05) and chemerin (men:-0.26 ng/ml; 95%-CI:-0.52 to-0.01 ng/ml; p<0.05; women:-0.41 ng/ml; 95%-CI:-0.82 to-0.01 ng/ml; p<0.05) as well as higher adiponectin concentrations (men: 0.06 µg/ml; 95%-CI: 0.02 to 0.11 µg/ml; p<0.05; women: 0.03 µg/ml; 95%-CI:-0.05 to 0.10 µg/ml; p=0.48). We found that CRF was inversely associated with leptin and chemerin in both sexes and positively associated with adiponectin only in men.

New Insights on the Relationship between Leptin, Ghrelin, and Leptin/Ghrelin Ratio Enforced by Body Mass Index in Obesity and Diabetes

Currently, adipose tissue is considered an endocrine organ, however, there are still many questions regarding the roles of adipokines—leptin and ghrelin being two adipokines. The purpose of the study was to assess the relationship between the adipokines and their ratio with obesity and diabetes. Methods: Sixty patients (mean age 61.88 ± 10.08) were evaluated. Cardiovascular risk factors, leptin, ghrelin, and insulin resistance score values were assessed. The patients were classified according to their body mass index (BMI) as normal weight, overweight, and obese. Results: 20% normal weight, 51.7% overweight, 28.3% obese, and 23.3% diabetic. Obese patients had higher leptin values (in obese 34,360 pg/mL vs. overweight 18,000 pg/mL vs. normal weight 14,350 pg/mL, p = 0.0049) and leptin/ghrelin ratio (1055 ± 641 vs. 771.36 ± 921 vs. 370.7 ± 257, p = 0.0228). Stratifying the analyses according to the presence of obesity and patients’ gender, differences were found for leptin (p = 0.0020 in women, p = 0.0055 in men) and leptin/ghrelin ratio (p = 0.048 in women, p = 0.004 in men). Mean leptin/BMI and leptin/ghrelin/BMI ratios were significantly higher, and the ghrelin/BMI ratio was significantly lower in obese and diabetic patients. In conclusion, obesity and diabetes are associated with changes not only in the total amount but also in the level of adipokines/kg/m². Changes appear even in overweight subjects, offering a basis for early intervention in diabetic and obese patients.

Association of Adiponectin, Leptin and Resistin Plasma Concentrations with Echocardiographic Parameters in Patients with Coronary Artery Disease

The imbalanced network of adipokines may contribute to the development of systemic low-grade inflammation, metabolic diseases and coronary artery disease (CAD). In the last decade, three classic adipokines—adiponectin, leptin and resistin—have been of particular interest in studies of patients with CAD due to their numerous properties in relation to the cardiovascular system. This has directed our attention to the association of adipokines with cardiac structure and function and the development of heart failure (HF), a common end effect of CAD. Thus, the purpose of this study was to analyse the associations of plasma concentrations of adiponectin, leptin and resistin with parameters assessed in the echocardiographic examinations of CAD patients. The presented study enrolled 167 Caucasian patients (133 male; 34 female) with CAD. Anthropometric, echocardiographic and basic biochemical measurements, together with plasma concentrations of adiponectin, leptin and resistin assays, were performed in each patient. Adiponectin concentrations were negatively associated with left ventricular ejection fraction (LVEF) and shortening fraction (LVSF), and positively associated with mitral valve E/A ratio (E/A), left ventricular end-diastolic volume (LVEDV), left ventricular end-diastolic diameter (LVEDD), left ventricular end-systolic diameter LVESD, and left atrium diameter (LAD). Resistin concentrations were negatively associated with E/A. Leptin concentrations, although correlated with HF severity assessed by the New York Heart Association (NYHA) Functional Classification, were not independently associated with the echocardiographic parameters of cardiac structure or function. In conclusion, adiponectin and resistin, but not leptin, are associated with the echocardiographic parameters of cardiac remodelling and dysfunction. These associations suggest that adiponectin and resistin might be involved in mechanisms of cardiac remodelling or compensative response. We also suggest the possible benefits of adiponectin and resistin level measurements in the monitoring of patients with CAD.

The interplay between statins and adipokines. Is this another explanation of statins' 'pleiotropic' effects?

Statin therapy comprises an integral part of secondary and to a lesser extent of primary cardiovascular disease prevention. This is attributed not only to their lipid-lowering properties, but as well to a plethora of pleiotropic actions. Recently, the cytokines secreted by adipose tissue, the so-called adipokines, have been proved to play a critical role in various pathophysiological functions, among which inflammation and atherosclerosis development and vulnerability. The aim of this literature review was to summarize the effects of statins and the underlying mechanisms on the circulating levels of the most common adipokines regulating atherosclerosis process, as a part of their pleiotropic function. Up to now, robust evidence implicates a significant statin-induced reduction of pro-inflammatory adipokines IL-6, TNF-a and visfatin. Weak evidence from limited, small and mostly non-randomized studies suggest increased levels of anti-inflammatory adipokines apelin, vaspin and omentin-1 after statin therapy. In the rest of most known adipokines, statins have shown either controversial (adiponectin, retinol binding protein-4 and fetuin-A) or negligible effects (leptin and resistin) on their circulating levels. Therefore, statins may favourably alter the balance of inflammatory/anti-inflammatory adipokines, implicating a novel atheroprotective mechanism. However, the interplay between statins and adipokines is still not fully elucidated and its potential clinical relevance is warranted.

Leptin mediate central obesity on the severity of cardiovascular autonomic neuropathy in well-controlled type 2 diabetes and prediabetes

BACKGROUND

Evidences support the view that central obesity is an independently cardiovascular risk. It is thought that leptin contributes to autonomic dysfunction and cardiovascular risks in type 1 and type 2 diabetes mellitus (T1DM and T2DM). This raises the possibility that leptin might mediate the relationship between central obesity and the severity of cardiovascular autonomic neuropathy (CAN) in patients with well-controlled T2DM and prediabetes.

METHODS

The complete cardiovascular reflex tests and biomarkers were assessed for each patient. The severity of CAN was assessed using composite autonomic scoring scale (CASS). A single-level three-variable mediation model was used to investigate the possible relationships among central obesity [as indicated by waist circumference (WC)], leptin level, and severity of CAN (as indicated by CASS value).

RESULTS

A total of 107 patients were included in this study: 90 with diabetes and 17 with prediabetes. The results demonstrate that increased WC is associated with increased severity of CAN (r = 0.242, P = 0.017). We further discovered that leptin level is positively correlated with WC (r = 0.504, P < 0.0001) and the CASS value (r = 0.36, P < 0.0001). Further mediation analysis shows that leptin level serves as mediators between higher WC and higher CASS.

CONCLUSIONS

Our results highlighted the relationship among leptin, central obesity, and severity of CAN. As the leptin level serves as mediator between central obesity and severity of CAN, a longitudinal study is needed to confirm that control of WC can decrease leptin levels and can be effective in reducing CAN progression.

Comparative effects of atorvastatin 80 mg and rosuvastatin 40 mg on the levels of serum endocan, chemerin, and galectin-3 in patients with acute myocardial infarction

OBJECTIVE

Endocan, chemerin, and galectin-3 are discrete biomarkers associated with cardiovascular diseases and acting through different pathophysiological pathways. The aim of this study is to investigate and compare the effects of high doses of atorvastatin and rosuvastatin on serum endocan, chemerin, and galectin-3 levels in patients with acute myocardial infarction (AMI).

METHODS

Sixty-three patients with AMI were randomized to receive atorvastatin (80 mg/day) or rosuvastatin (40 mg/day) after percutaneous revascularization. Serum levels of endocan, chemerin, and galectin-3 were evaluated at baseline and after 4-week therapy.

RESULTS

Endocan levels were not decreased statistically significantly with atorvastatin 80 mg, but rosuvastatin 40 mg markedly decreased the levels of endocan according to baseline [from 110.27 (86.03-143.69) pg/mL to 99.22 (78.30-122.87) pg/mL with atorvastatin 80 mg and from 110.73 (77.28-165.22) pg/mL to 93.40 (70.48-115.13) pg/mL with rosuvastatin 40 mg, p=0.242 for atorvastatin 80 mg and p=0.014 for rosuvastatin 40 mg]. Chemerin levels significantly decreased in both groups according to baseline [from 264.90 (196.00-525.95) ng/mL to 135.00 (105.95-225.65) ng/mL with atorvastatin 80 mg and from 309.95 (168.87-701.27) ng/mL to 121.25 (86.60-212.65) ng/mL with rosuvastatin 40 mg, p<0.001, respectively, for both groups]. Galectin-3 levels did not change markedly with atorvastatin 80 mg, but they decreased with rosuvastatin 40 mg [from 17.00 (13.10-22.25) ng/mL to 19.30 (15.25-23.45) ng/mL with atorvastatin 80 mg, p=0.721, and from 18.25 (12.82-23.82) ng/mL to 16.60 (10.60-20.15) ng/mL with rosuvastatin 40 mg, p=0.074]. There were no significant between-group differences in terms of absolute and percentage changes of endocan, chemerin, and galectin-3 at 4 weeks.

CONCLUSION

We reported that both statins similarly decreased the endocan levels, whereas rosuvastatin seems to have more prominent effects on the reduction of the chemerin and galectin-3 levels in patients with AMI.

Impact of postdiagnostic statin use on ovarian cancer mortality: A systematic review and meta-analysis of observational studies

AIMS

To comprehensively evaluate the association between postdiagnostic statin use and mortality of ovarian cancer (OC) patients.

METHODS

Using a comprehensive strategy, multiple databases (Medline, Embase and Web of Science) were systematically searched to identify observational studies that examined the correlation between statin use and OC mortality up to 31 December 2017. The studies were independently reviewed and selected based on predetermined selection criteria. Data were extracted independently and in duplicate. The risk of bias was evaluated with the Newcastle-Ottawa scale. Hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were summarized with a profile likelihood random effects model.

RESULTS

Of 269 studies, eight cohort studies of 19 904 OC patients met the inclusion criteria. Postdiagnostic statin use was inversely associated with all-cause mortality/overall survival (summarized HR = 0.74; 95%CI = 0.63-0.87; I²  = 55%; n = 7) and cancer-specific mortality (summarized HR = 0.87; 95%CI = 0.80-0.95; I²  = 0%; n = 3) of OC patients. These findings were consistent by subgroup analyses stratified by study and patient characteristics as well as adjustments made for potential confounders. A meta-regression analysis found no effect of modification by these variables. Of note, similar significant inverse effects were also observed when increasing the intensity (highest vs. lowest) of postdiagnostic statin use (summarized HR = 0.84; 95%CI = 0.74-0.96; I²  = 0%; n = 3).

CONCLUSION

Postdiagnostic statin use can improve the survival of patients with OC. Further prospective cohort and randomized controlled trials are warranted to confirm the therapeutic role of statin use on the outcome of OC.

Functional Implications of HMG-CoA Reductase Inhibition on Glucose Metabolism

HMG-CoA reductase inhibitors, i.e. statins, are effective in reducing cardiovascular disease events but also in cardiac-related and overall mortality. Statins are in general well-tolerated, but currently the concerns are raised if statins may increase the risk of new-onset diabetes mellitus (NOD). In this review, the possible effects of statins on organs/tissues being involved in glucose metabolism, i.e. liver, pancreas, adipose tissue, and muscles, had been discussed. The net outcome seems to be inconsistent and often contradictory, which may be largely affected by in vitro experimental settings or/and in vivo animal conditions. The majority of studies point out statin-induced changes of regulations of isoprenoid metabolites and cell-associated cholesterol contents as predisposing factors related to the statin-induced NOD. On the other hand, it should be considered that dysfunctions of isoprenoid pathway and mitochondrial ATP production and the cholesterol homeostasis are already developed under (pre)diabetic and hypercholesterolemic conditions. In order to connect the basic findings with the clinical manifestation more clearly, further research efforts are needed.

Impact of Statin Therapy on Plasma MMP-3, MMP-9, and TIMP-1 Concentrations: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials

Tissue inhibitors of metalloproteinases (TIMPs) and matrix metalloproteinases (MMPs) are associated with the development of atherosclerosis and cardiovascular disease. Statin therapy has been shown to modulate MMPs and TIMP-1 levels, but clinical findings have not been conclusive. This study aimed to systematically review the clinical findings on the impact of statin therapy on plasma MMP-9, MMP-3, and TIMP-1 levels and calculate an effect size for the mentioned effect through a meta-analysis of available data. A total of 10 eligible studies with 11 treatment arms were included in the meta-analysis. Statin therapy had no significant effect on plasma MMP-9 (standardized mean difference [SMD]: −0.23, 95% confidence interval [CI]: −0.69 to 0.24, P = .345) nor MMP-3 concentrations (SMD: −0.004, 95% CI: −0.60 to 0.59, P = .990). However, meta-analysis demonstrated that statin therapy significantly decreases plasma TIMP-1 levels (SMD: −0.30, 95% CI: −0.56 to −0.03, P = .029). Random-effects meta-regression indicated that neither treatment duration nor changes in low-density lipoprotein cholesterol levels are associated with changes in plasma MMP-9 levels following statin therapy. The results of the present meta-analysis suggested a significant reduction in plasma concentrations of TIMP-1, but not MMP-9 and MMP-3, following statin therapy.

Impact of statin therapy on plasma leptin concentrations: a systematic review and meta-analysis of randomized placebo-controlled trials

OBJECTIVES

The effects of statins on insulin sensitivity, metabolic homeostasis and adipokines in humans are controversial. Several studies have investigated the impact of statin therapy on plasma leptin concentrations but the results have been inconsistent. The aim of the present study was to conduct a systematic review and meta-analysis of available evidence to calculate the effect size of statin therapy in changing serum leptin concentrations.

METHODS

A systematic search in PubMed-Medline, SCOPUS, Web of Science and Google Scholar databases was performed to identify randomized placebo-controlled trials investigating the effect of statins on plasma leptin concentrations. A random-effects model and generic inverse variance method were used for meta-analysis. Sensitivity analysis, risk-of-bias evaluation and publication bias assessment were carried out using standard methods. Random-effects meta-regression was used to evaluate the impact of treatment duration on the estimated effect size.

RESULTS

Six trials, with a total of 425 subjects, met the eligibility criteria. Overall, statin therapy had no significant effect on leptin levels (weighted mean difference -0.32 ng ml^-1 , 95% confidence nterval: -2.94, 2.30, P = 0.813). This effect was robust in the sensitivity analysis and in subgroup analyses of trials with <12 or ≥12 weeks' duration. There was no association between the duration of statin therapy and changes in plasma leptin levels. Furthermore, there was no differential effect of hydrophilic and lipophilic statins on plasma leptin concentrations.

CONCLUSION

Unless more consistent evidence becomes available in the future, the hypothesis of a relationship between statin use and serum leptin concentrations seem to be unfounded.