New advances of adiponectin in regulating obesity and related metabolic syndromes

Obesity and related metabolic syndromes have been recognized as important disease risks, in which the role of adipokines cannot be ignored. Adiponectin (ADP) is one of the key adipokines with various beneficial effects, including improving glucose and lipid metabolism, enhancing insulin sensitivity, reducing oxidative stress and inflammation, promoting ceramides degradation, and stimulating adipose tissue vascularity. Based on those, it can serve as a positive regulator in many metabolic syndromes, such as type 2 diabetes (T2D), cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD), sarcopenia, neurodegenerative diseases, and certain cancers. Therefore, a promising therapeutic approach for treating various metabolic diseases may involve elevating ADP levels or activating ADP receptors. The modulation of ADP genes, multimerization, and secretion covers the main processes of ADP generation, providing a comprehensive orientation for the development of more appropriate therapeutic strategies. In order to have a deeper understanding of ADP, this paper will provide an all-encompassing review of ADP.

The Effects of Statin Dose, Lipophilicity, and Combination of Statins plus Ezetimibe on Circulating Oxidized Low-Density Lipoprotein Levels: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Elevated plasma low-density lipoprotein cholesterol (LDL-C) is the main risk factor for atherosclerotic cardiovascular disease (ASCVD). Statins are the drugs of choice for decreasing LDL-C and are used for the prevention and management of ASCVD. Guidelines recommend that subjects with high and very high ASCVD risk should be treated with high-intensity statins or a combination of high-intensity statins and ezetimibe. The lipophilicity or hydrophilicity (solubility) of statins is considered to be important for at least some of their LDL-C lowering independent pleiotropic effects. Oxidative modification of LDL (ox-LDL) is considered to be the most important atherogenic modification of LDL and is supposed to play a crucial role in atherogenesis and ASCVD outcomes.

Objective

The aim of this systematic review and meta-analysis was to find out what are the effects of statin intensity, lipophilicity, and combination of statins plus ezetimibe on ox-LDL.

Methods

PubMed, Scopus, Embase, and Web of Science were searched from inception to February 5, 2021, for randomized controlled trials (RCTs). Two independent and blinded authors evaluated eligibility by screening the titles and abstracts of the studies. Risk of bias in the studies included in this meta-analysis was evaluated according to the Cochrane instructions. Meta-analysis was performed using Comprehensive Meta-Analysis (CMA) V2 software. Evaluation of funnel plot, Begg's rank correlation, and Egger's weighted regression tests were used to assess the presence of publication bias.

Results

Among the 1427 published studies identified by a systematic databases search, 20 RCTs were finally included in the systematic review and meta-analysis. A total of 1874 patients are included in this meta-analysis. This meta-analysis suggests that high-intensity statin treatment is associated with a significant decrease in circulating concentrations of ox-LDL when compared with low-to-moderate treatment (SMD: -0.675, 95% CI: -0.994, -0.357, p < 0.001; I²: 55.93%). There was no difference concerning ox-LDL concentration between treatments with hydrophilic and lipophilic statins (SMD: -0.129, 95% CI: -0.330, -0.071, p = 0.206; I²: 45.3%), but there was a significant reduction in circulating concentrations of ox-LDL associated with statin plus ezetimibe combination therapy when compared with statin monotherapy (SMD: -0.220, 95% CI: -0.369, -0.071, p = 0.004; I²: 0%).

Conclusion

High-dose statin or combination of statins with ezetmibe reduces plasma ox-LDL in comparison low-to-moderate intensity statin therapy alone. Statin lipophilicity is not associated with reduction in ox-LDL plasma concentrations.

Investigation of the synergistic effect of glimepiride and rosuvastatin on alloxan-induced diabetic rat

Purpose

Diabetes mellitus is characterized by having a multitude of life-threatening secondary complications, particularly dyslipidemia, which ultimately leads to the development of comorbid diseases, such as cardiovascular diseases. This research work was designed to investigate the synergistic effect of glimepiride (1 mg/kg b.w.) and rosuvastatin (10 mg /kg b.w.) on alloxan-induced diabetic rats having dyslipidemia.

Methods

Diabetes was induced by injecting alloxan (120 mg/kg b.w.) intraperitoneally. The experiment was conducted to determine the level of blood glucose, HbA1c, lipid profile, and body weight variation of rats.

Results

This study's outcomes suggested that the combination therapy showed more statistically significant effect on blood glucose level, HbA1c level, lipid profile, and body weight variation than any single therapy. While the glimepiride monotherapy showed a statistically considerable effect on blood glucose level, HbA1c level, and body weight variation, the rosuvastatin treated group gave statistically non-significant effect on these parameters except body weight variation, which was found as downward trend. In addition, the rosuvastatin treated group showed a healthy lipid profile compared to glimepiride treated group.

Conclusions

Concluding the results of this study, it can be said that the treatment of glimepiride in combination with rosuvastatin may be more efficacious than monotherapy for preventing diabetes in rats with dyslipidemia.

Adiponectin: The Potential Regulator and Therapeutic Target of Obesity and Alzheimer's Disease

Animal and human mechanistic studies have consistently shown an association between obesity and Alzheimer’s disease (AD). AD, a degenerative brain disease, is the most common cause of dementia and is characterized by the presence of extracellular amyloid beta (Aβ) plaques and intracellular neurofibrillary tangles disposition. Some studies have recently demonstrated that Aβ and tau cannot fully explain the pathophysiological development of AD and that metabolic disease factors, such as insulin, adiponectin, and antioxidants, are important for the sporadic onset of nongenetic AD. Obesity prevention and treatment can be an efficacious and safe approach to AD prevention. Adiponectin is a benign adipokine that sensitizes the insulin receptor signaling pathway and suppresses inflammation. It has been shown to be inversely correlated with adipose tissue dysfunction and may enhance the risk of AD because a range of neuroprotection adiponectin mechanisms is related to AD pathology alleviation. In this study, we summarize the recent progress that addresses the beneficial effects and potential mechanisms of adiponectin in AD. Furthermore, we review recent studies on the diverse medications of adiponectin that could possibly be related to AD treatment, with a focus on their association with adiponectin. A better understanding of the neuroprotection roles of adiponectin will help clarify the precise underlying mechanism of AD development and progression.

Statin Lipophilicity and the Risk of Incident Heart Failure

BACKGROUND

To compare the risk of incident heart failure (HF) between initiators of hydrophilic and lipophilic statins.

METHODS

Using claims data for commercial health insurance program enrollees in the USA (2005-2014), we identified new initiators of hydrophilic or lipophilic statins. Follow-up for the primary outcome of incident HF began after a lag period of 1 year after statin initiation. The outcome was defined as 1 inpatient or 2 outpatient diagnosis codes for HF and the use of loop diuretics. Propensity scores (PS) were used to account for confounding. Hazard ratios (HR) for incident HF were computed separately for low and high-intensity statin users, and then pooled to provide dose-adjusted effect estimates.

RESULTS

A total of 7,820,204 patients met all our inclusion criteria for statin initiation (hydrophilic and lipophilic statins). Mean age was 58 years, 40% had hypertension, and 23% had diabetes mellitus. After PS matching, there were 691,584 patients in the low-intensity statin group and 807,370 patients in the high-intensity statin group. After a median follow-up of 725 days (IQR 500-1,153),there were 8,389 cases of incident HF (incidence rate 4.5/1,000 person years, 95% confidence interval [CI] 4.4-4.6). The unadjusted HR for the risk of HF was 0.77 (95% CI 0.76-0.79) and the pooled adjusted HR for incident HF after PS matching was 0.94 (95% CI 0.90-0.98) for hydrophilic versus lipophilic statins. The HR for incident HF was 1.06 (95% CI 1.00-1.12) for hydrophilic versus lipophilic statins for the low-intensity statin group and 0.82 (95% CI 0.78-0.87) for the high-intensity statin group. In subgroup analyses, a similar trend persisted for those younger and older than 65 years and when comparing rosuvastatin with atorvastatin.

CONCLUSION

In this observational cohort study, hydrophilic statins were associated with a modest risk reduction in incident HF as compared to lipophilic statins. Future research replicating these findings in different populations is recommended.

Hydrophilic vs. Lipophilic Statins in Diabetic Patients - Comparison of Long-Term Outcomes After Acute Myocardial Infarction

Background: Studies comparing the cardiac consequences of hydrophilic and lipophilic statins in experimental and clinical practice settings have produced inconsistent results. In particular, evidence focusing on diabetic patients after acute myocardial infarction (AMI) is lacking.

Methods and Results: From the Osaka Acute Coronary Insufficiency Study (OACIS) registry database, 1,752 diabetic patients with AMI who were discharged with a prescription for statins were studied. Long-term outcomes were compared between hydrophilic and lipophilic statins, including all-cause death, recurrent myocardial infarction (re-MI) and admission for heart failure (HF) and a composite of these (major adverse cardiac events; MACE). During a median follow-up period of 1,059 days, all-cause death, non-fatal re-MI, admission for HF, and MACE occurred in 95, 89, 112 and 249 patients, respectively. Although there was no significant difference between statins in the risk of all-cause death, re-MI and MACE, the risk of HF admission was significantly lower in patients with hydrophilic than lipophilic statins before (adjusted hazard ratio [aHR], 0.560; 95% CI: 0.345–0.911, P=0.019) and after (aHR, 0.584; 95% CI: 0.389–0.876, P=0.009) propensity score matching. Hydrophilic statin use was consistently associated with lower risk for HF admission than lipophilic statins across the subgroup categories.

Conclusions: In the present diabetic patients with AMI, hydrophilic statins were associated with a lower risk of admission for HF than lipophilic statins.

Adiponectin, Obesity, and Cancer: Clash of the Bigwigs in Health and Disease

Adiponectin is one of the most important adipocytokines secreted by adipocytes and is called a “guardian angel adipocytokine” owing to its unique biological functions. Adiponectin inversely correlates with body fat mass and visceral adiposity. Identified independently by four different research groups, adiponectin has multiple names; Acrp30, apM1, GBP28, and AdipoQ. Adiponectin mediates its biological functions via three known receptors, AdipoR1, AdipoR2, and T-cadherin, which are distributed throughout the body. Biological functions of adiponectin are multifold ranging from anti-diabetic, anti-atherogenic, anti-inflammatory to anti-cancer. Lower adiponectin levels have been associated with metabolic syndrome, type 2 diabetes, insulin resistance, cardiovascular diseases, and hypertension. A plethora of experimental evidence supports the role of obesity and increased adiposity in multiple cancers including breast, liver, pancreatic, prostrate, ovarian, and colorectal cancers. Obesity mediates its effect on cancer progression via dysregulation of adipocytokines including increased production of oncogenic adipokine leptin along with decreased production of adiponectin. Multiple studies have shown the protective role of adiponectin in obesity-associated diseases and cancer. Adiponectin modulates multiple signaling pathways to exert its physiological and protective functions. Many studies over the years have shown the beneficial effect of adiponectin in cancer regression and put forth various innovative ways to increase adiponectin levels.

Effects of switching to low-dose rosuvastatin (5 mg/day) on glucose metabolism and lipid profiles in Japanese patients with type 2 diabetes and dyslipidemia: a single-arm, prospective, interventional trial

Aims

We investigated the effects of switching from other statins, such as pravastatin (5 or 10 mg/day), rosuvastatin (2.5 mg/day), or pitavastatin (1 or 2 mg/day), to low-dose rosuvastatin (5 mg/day) on glucose metabolism and lipid profiles in Japanese patients with type 2 diabetes and dyslipidemia.

Methods

This was a prospective, two-center, open-label, single-arm, interventional trial. Several clinical parameters were analyzed at baseline and 24 weeks after switching from other statins to rosuvastatin at 5 mg/day. The primary endpoints were changes in hemoglobin (Hb) A1c level and lipid profile.

Results

Forty-five patients were enrolled in the trial. The mean HbA1c level increased significantly from 7.1 ± 0.7 to 7.5 ± 0.9% (P < 0.001), whereas the mean low-density lipoprotein cholesterol (LDL-C) level decreased significantly from 108.9 ± 16.5 to 91.6 ± 24.5 mg/dL (P < 0.001). Multiple linear regression analysis showed that changes in HbA1c levels were significantly and positively correlated with fasting plasma glucose (FPG) levels at baseline. Receiver operating characteristic (ROC) curve analysis examining the relationship between HbA1c and FPG showed that FPG was a significant predictor of changes in HbA1c levels (area under the curve, 0.72). The cutoff FPG value of 168 mg/dL had a sensitivity of 47% and a specificity of 93%.

Conclusions

Switching to a low dose of rosuvastatin impaired glucose metabolism in Japanese patients with type 2 diabetes and dyslipidemia. Patients with high FPG levels were particularly prone to an exacerbation of glucose metabolism.

Circulating Omentin-1 Levels Are Decreased in Dilated Cardiomyopathy Patients with Overt Heart Failure

Background. Recent evidence demonstrated that the circulating levels of omentin-1 are related to the presence of ischemic heart disease and heart failure. However, omentin-1 plasma levels in patients with nonischemic dilated cardiomyopathy (DCM), which is the most common etiology of heart failure, have yet to be investigated. Methods. Plasma levels of omentin-1 and adiponectin were measured in 100 patients with DCM and 45 healthy controls. Results. Plasma omentin-1 levels significantly decreased in DCM patients compared with the control group, whereas adiponectin levels significantly increased in DCM patients compared with the control group. Plasma omentin-1 levels were negatively correlated with adiponectin (R = −0.376, P = 0.005), C-reactive protein (CRP) (R = −0.320, P = 0.001), and N-terminal pro-brain natriuretic peptide (NT-proBNP) (R = −0.365, P = 0.000) levels as well as left ventricular end-diastolic diameter (LVEDD) (R = −0.200, P = 0.046) but were positively correlated with left ventricular ejection fraction (LVEF) (R = 0.496, P = 0.000). Plasma adiponectin levels were positively correlated with CRP (R = 0.273, P = 0.006) and NT-proBNP (R = 0.329, P = 0.001) levels but were negatively correlated with fasting glucose (R = −0.218, P = 0.029) and LVEF (R = −0.615, P = 0.000) levels. Furthermore, omentin-1 (OR 0.983, 95% CI 0.970 to 0.996; P = 0.008) levels were independently associated with the presence of DCM before NT-proBNP was added. Conclusions. Omentin-1 is a novel biomarker of DCM.

Aortic valve sclerosis is associated with lower serum adiponectin levels

AIMS

The sclerotic lesions of the aortic valve share common features with atherosclerosis. An anti-inflammatory protein, adiponectin, seems to have a protective effect on the cardiovascular system. The goal of our study is to determine adiponectin levels in patients with aortic sclerosis and to compare these values with the control group with similar age and cardiovascular risk profile.

METHODS

Sixty-eight patients with aortic sclerosis and 40 controls were included. Serum adiponectin levels were measured by solid-phase enzyme-linked immunosorbent assay.

RESULTS

There were no significant differences regarding age, sex and other cardiovascular risk factors between groups. Also, mean body mass index values were similar. The rate of mitral annular calcification and left ventricular hypertrophy were significantly higher in patients with aortic sclerosis. Among laboratory variables, high-sensitive C-reactive protein (hsCRP) levels were significantly higher in patients with aortic sclerosis than in those without (4.0 ± 2.9 vs. 2.9 ± 2.3 mg/dl, P = 0.04). Adiponectin levels were found to be significantly lower in aortic sclerosis group than in controls (9.7 ± 4.4 vs. 11.7 ± 4.9 μg/ml, P = 0.034). In the whole group, adiponectin levels were significantly correlated with BMI (r = -0.22, P = 0.02), white blood cell count (r = -0.2, P = 0.03), hsCRP (r = -0.25, P = 0.008), total cholesterol (r = -0.18, P = 0.05), high-density lipoprotein (HDL) cholesterol (r = 0.31, P = 0.001) and triglyceride (r = -0.36, P < 0.001).

CONCLUSION

In patients with aortic sclerosis, serum adiponectin levels were significantly lower compared with those with normal aortic valves. Our findings suggested that adiponectin might play a role in the progression of degenerative aortic valve disease.

Effects of simvastatin treatment on serum adiponectin concentrations in patients with dislipidemia

Background:

Adiponectin is an adipose tissue-derived protein with anti-inflammatory properties. Statins are a class of cholesterol-lowering drugs, widely used for treatment of cardiovascular diseases.

Objectives:

In the current study, we aimed to assess the effects of simvastatin on serum levels of adiponectin in patients with dyslipidemia, recruited from Ghaem Hospital, Mashhad, Iran.

Materials and Methods:

A total of 102 patients with dyslipidemia were treated with simvastatin or placebo during a double-blind, cross-over, placebo-controlled trial. The adiponectin levels were measured before and after each treatment period. Seventy seven participants completed the study.

Results:

There was a significant reduction in serum total cholesterol (approxmately 21%), low density lipoprotein-cholesterol (LDL-C) (approxmately 28%), and triglycerides (approxmately 11%), after four weeks of treatment with simvastatin (P < 0.001).

Conclusions:

No significant change in serum adiponectin concentrations was observed after treatment with simvastatin. This may be because of the relatively short duration of treatment and longer treatment duration may be necessary to investigation in future studies.

Lipophilic versus hydrophilic statin therapy for heart failure: a protocol for an adjusted indirect comparison meta-analysis

BACKGROUND

Statins are known to reduce cardiovascular morbidity and mortality in primary and secondary prevention studies. Subsequently, a number of nonrandomised studies have shown statins improve clinical outcomes in patients with heart failure (HF). Small randomised controlled trials (RCT) also show improved cardiac function, reduced inflammation and mortality with statins in HF. However, the findings of two large RCTs do not support the evidence provided by previous studies and suggest statins lack beneficial effects in HF. Two meta-analyses have shown statins do not improve survival, whereas two others showed improved cardiac function and reduced inflammation in HF. It appears lipophilic statins produce better survival and other outcome benefits compared to hydrophilic statins. But the two types have not been compared in direct comparison trials in HF.

METHODS/DESIGN

We will conduct a systematic review and meta-analysis of lipophilic and hydrophilic statin therapy in patients with HF. Our objectives are:1. To determine the effects of lipophilic statins on (1) mortality, (2) hospitalisation for worsening HF, (3) cardiac function and (4) inflammation.2. To determine the effects of hydrophilic statins on (1) mortality, (2) hospitalisation for worsening HF, (3) cardiac function and (4) inflammation.3. To compare the efficacy of lipophilic and hydrophilic statins on HF outcomes with an adjusted indirect comparison meta-analysis.We will conduct an electronic search of databases for RCTs that evaluate statins in patients with HF. The reference lists of all identified studies will be reviewed. Two independent reviewers will conduct the search. The inclusion criteria include:1. RCTs comparing statins with placebo or no statin in patients with symptomatic HF.2. RCTs that employed the intention-to-treat (ITT) principle in data analysis.3. Symptomatic HF patients of all aetiologies and on standard treatment.4. Statin of any dose as intervention.5. Placebo or no statin arm as control.The exclusion criteria include:1. RCTs involving cerivastatin in HF patients.2. RCTs with less than 4 weeks of follow-up.

DISCUSSION

We will perform an adjusted indirect comparison meta-analysis of lipophilic versus hydrophilic statins in patients with HF using placebo or no statin arm as common comparator.

Statin treatment for patients with heart failure

Statins may be beneficial for the prevention and treatment of heart failure, as indicated by large observational studies, small prospective studies, and post hoc analyses of cardiovascular databases. Two large, prospective, controlled trials have, however, shown that rosuvastatin has neutral effects on the survival of patients with chronic heart failure. The benefits of statin treatment seem to mostly result from their ability to halt disease progression in heart failure, particularly in patients with coronary artery disease. Based on these results, statin treatment might only be useful for the prevention of heart failure, and possibly in patients with new-onset heart failure. This Review highlights data from observational data analyses as well as from the large prospective trials investigating the safety and efficacy of statins in patients with heart failure. The results from these studies and their implications for the timing of initiating statin therapy in this patient population are also discussed.

Cholesterol in beta-cell dysfunction: the emerging connection between HDL cholesterol and type 2 diabetes

Beta-cell dysfunction is a critical step in the pathogenesis of type 2 diabetes. The mechanisms responsible for beta-cell death and dysfunction remain incompletely understood, but include glucolipotoxicity, the deleterious metabolic milieu created by high plasma concentrations of glucose and lipid species. Recently, an important role has emerged for cholesterol in this process. In this article, we review recent advances in our understanding of the role of ABCA1 and cholesterol metabolism in beta-cell function, with particular attention to insights gained from human studies.