Acute onset and worsening of diabetes concurrent with administration of statins

High doses of rosuvastatin induce impaired branched-chain amino acid catabolism and lead to insulin resistance

NEW FINDINGS

What is the central question of this study? Is there a risk of developing diabetes associated with statin treatment? What is the underlying mechanism of the increased incidence rate of new-onset diabetes in patients treated with rosuvastatin? What is the main finding and its importance? Rosuvastatin therapy reduced intraperitoneal glucose tolerance and changed the catabolism of branched-chain amino acid (BCAAs) in white adipose tissue and skeletal muscle. Protein phosphatase 2Cm knockdown completely abolished the effects of insulin and rosuvastatin on glucose absorption. This study provides mechanistic support for recent clinical data on rosuvastatin-related new-onset diabetes and underscores the logic for intervening in BCAA catabolism to prevent the harmful effects of rosuvastatin.

ABSTRACT

Accumulating evidence indicates that patients treated with rosuvastatin have an increased risk of developing new-onset diabetes. However, the underlying mechanism remains unclear. In this study, we administered rosuvastatin (10 mg/kg body weight) to male C57BL/6J mice for 12 weeks and found that oral rosuvastatin dramatically reduced intraperitoneal glucose tolerance. Rosuvastatin-treated mice showed considerably higher serum levels of branched-chain amino acids (BCAAs) than control mice. They also showed dramatically altered expression of BCAA catabolism-related enzymes in white adipose tissue and skeletal muscle, including downregulated mRNA expression of BCAT2 and protein phosphatase 2Cm (PP2Cm) and upregulated mRNA expression of branched-chain ketoacid dehydrogenase kinase (BCKDK). The levels of BCKD in the skeletal muscle were reduced in rosuvastatin-treated mice, which was associated with lower PP2Cm protein levels and increased BCKDK levels. We also investigated the effects of rosuvastatin and insulin administration on glucose metabolism and BCAA catabolism in C2C12 myoblasts. We observed that incubation with insulin enhanced glucose uptake and facilitated BCAA catabolism in C2C12 cells, which was accompanied by elevated Akt and glycogen synthase kinase 3 β (GSK3β) phosphorylation. These effects of insulin were prevented by co-incubation of the cells with 25 μM rosuvastatin. Moreover, the effects of insulin and rosuvastatin administration on glucose uptake and Akt and GSK3β signaling in C2C12 cells were abolished when PP2Cm was knocked down. Although the relevance of these data, obtained with high doses of rosuvastatin in mice, to therapeutic doses in humans remains to be elucidated, this study highlights a potential mechanism for the diabetogenic effects of rosuvastatin, and suggests that BCAA catabolism could be a pharmacological target for preventing the adverse effects of rosuvastatin.

Amyotrophic Lateral Sclerosis Associated with Statin Use: A Disproportionality Analysis of the FDA's Adverse Event Reporting System

INTRODUCTION

Apparent elevations in reporting of amyotrophic lateral sclerosis (ALS)-like conditions associated with statin use have been previously described from data obtained via US and European databases.

OBJECTIVE

The aim of this study was to examine US FDA Adverse Event Reporting System (FAERS) data to compare reporting odds ratios (RORs) of ALS and ALS-like conditions between statins and other drugs, for each statin agent.

METHODS

We assessed for disproportional rates of reported ALS and ALS-related conditions for each statin agent separately by using the ROR formula. FAERS data were analyzed through September 2015.

RESULTS

RORs for ALS were elevated for all statins, with elevations possibly stronger for lipophilic statins. RORs ranged from 9.09 (6.57-12.6) and 16.2 (9.56-27.5) for rosuvastatin and pravastatin (hydrophilic) to 17.0 (14.1-20.4), 23.0 (18.3-29.1), and 107 (68.5-167) for atorvastatin, simvastatin, and lovastatin (lipophilic), respectively. For simvastatin, an ROR of 57.1 (39.5-82.7) was separately present for motor neuron disease.

CONCLUSION

These findings extend previous evidence showing that significantly elevated ALS reporting extends to individual statin agents, and add to concerns about potential elevated occurrence of ALS-like conditions in association with statin usage.

Assessment of Atorvastatin Effect on Body Weight and Blood Glucose Levels Among Diabetic and Non-Diabetic Patients

Background and aims: Atorvastatin is a member of the drug class known as statins, which used as a lipid-lowering agent. The study aim was to assess the effect of atorvastatin on body weight and blood glucose levels among diabetic and non-diabetic patients.

Material and Methods: A 359 hyperlipidemic Jordanian patients using atorvastatin at least for 1 year were divided into two groups: diabetic (DM) and non-diabetic (NDM). The changes in lipid profile, thyroid function test, blood glucose indices as well as body weight were assessed and compared between both groups.

Results: There was no statistical significant (p > 0.05) difference between means of body weight after treatment among DM (85.74 ± 3.56) and NDM (81.75 ± 1.25) groups. Descriptive statistics and mean comparisons before and after atorvastatin treatment, showed statistical significant (p ≤ 0.05) differences in body weight and total cholesterol among NDM group and in total cholesterol and LDL-Ch among DM group. There was an increase in fasting blood glucose (FBG) and glycated hemoglobin A1c (HbA1c) and a decrease in triglycerides among both groups but the difference was not statistically (p > 0.05) significant.

Conclusions: Atorvastatin may increase body weight, fasting blood glucose and HbA1c for diabetic and non-diabetic patients.

Dual Effect of Rosuvastatin on Glucose Homeostasis Through Improved Insulin Sensitivity and Reduced Insulin Secretion

Statins are beneficial in the treatment of cardiovascular disease (CVD), but these lipid-lowering drugs are associated with increased incidence of new on-set diabetes. The cellular mechanisms behind the development of diabetes by statins are elusive. Here we have treated mice on normal diet (ND) and high fat diet (HFD) with rosuvastatin. Under ND rosuvastatin lowered blood glucose through improved insulin sensitivity and increased glucose uptake in adipose tissue. In vitro rosuvastatin reduced insulin secretion and insulin content in islets. In the beta cell Ca^2 + signaling was impaired and the density of granules at the plasma membrane was increased by rosuvastatin treatment. HFD mice developed insulin resistance and increased insulin secretion prior to administration of rosuvastatin. Treatment with rosuvastatin decreased the compensatory insulin secretion and increased glucose uptake. In conclusion, our data shows dual effects on glucose homeostasis by rosuvastatin where insulin sensitivity is improved, but beta cell function is impaired.

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Rosuvastatin lowered blood glucose in vivo most likely due to improved glucose uptake.

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Rosuvastatin reduced insulin content and impaired Ca^2 + signaling in beta cells leading to reduced insulin secretion.

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Dual effects of rosuvastatin in HFD mice though decreased compensatory insulin secretion and increased glucose uptake.

Statins are a group of drugs used to lower blood cholesterol in individuals with a risk of developing cardiovascular disease. It has been shown in several studies that statins increase the risk of developing type 2 diabetes. This increased risk has not yet been explained. We have investigated the effect of rosuvastatin on blood glucose regulation in mice. We found that rosuvastatin has a beneficial effect on glucose uptake in muscles which results in lowered blood glucose. However, in the insulin producing beta cells rosuvastatin altered normal cell function something that might increase the risk of developing type 2 diabetes.

Statin Use and the Risk for Incident Diabetes Mellitus in Patients with Acute Coronary Syndrome after Percutaneous Coronary Intervention: A Population-Based Retrospective Cohort Study in Taiwan

OBJECTIVES

The purpose of this study was to examine the association between statin use by individuals and the risk for incident diabetes mellitus in patients with acute coronary syndrome (ACS) following percutaneous coronary intervention (PCI).

METHODS

We conducted a retrospective cohort study of patients who were hospitalized for ACS between January 1, 2006, and December 31, 2010, and who had undergone PCI (n=30,665); the data were retrieved from the Taiwan National Health Insurance Research Database. A propensity score technique was used to establish a 1:1 matched cohort for statin users and non-statin users (n=9043 for each group). The risk for incident diabetes mellitus in statin users compared to non-statin users for patients with ACS after PCI was estimated by the multivariable Cox proportional hazards regression model.

RESULTS

Statin use was associated with a significant increase of 27% in the risk for new-onset diabetes mellitus (adjusted hazard ratio [HR] 1.27, 95% CI 1.14 to 1.41) compared to non-statin use in the matched cohort. The matched cohort analysis indicated that almost all individual statins were associated with a statistically significant increase in the risk for new-onset diabetes mellitus compared to those without statin use.

CONCLUSIONS

Our study indicated an association between increased risk for new-onset diabetes mellitus and statin use. Because the benefits of statins in prevention of morbidity and mortality in patients with ACS are well-established, clinical decision making should not be changed for patients with existing cardiovascular disease in whom statin therapy is recommended.

The effect of simvastatin on glucose homeostasis in streptozotocin induced type 2 diabetic rats

Objective. To investigate the effect of simvastatin on glucose homeostasis in streptozotocin induced type 2 diabetic rats. Methods. Forty male Wistar rats were randomly divided into four groups. Normal control rats were fed with standard diet, others were fed with high-fat diet. Diabetic rats were induced by a single intraperitoneal injection of STZ. The simvastatin intervention rats were fed with simvastatin during the experiment process, and the simvastatin treatment rats were fed with simvastatin after diabetes rats were induced. We measured body weight, fasting plasma glucose, cholesterol, high-density lipoprotein cholesterol, and triglyceride after an overnight fast. Results. The FPG was higher in diabetic rats when compared to normal control ones; the simvastatin intervention rats had a higher FPG compared to the diabetic rats and were more easily be induced to diabetes at the end of 4 weeks, FPG level of simvastatin treatment rats was increased compared with diabetic model rats after 12 weeks. Conclusion. These data indicate that simvastatin intervention rats may cause hyperglycemia by impairing the function of islet β cells and have an adverse effect on glucose homeostasis, especially on FPG level.

Inhibition of the renal renin-angiotensin system and renoprotection by pitavastatin in type1 diabetes

1. The aim of the present study was to investigate whether or not pitavastatin ameliorates diabetic nephropathy and if inhibition of the rennin-angiotensin-aldosterone system (RAAS) is associated with any renoprotective effects. Pitavastatin (10mg/ kg/day) and/or spironolactone (100mg/kg/day) were given by gavage for 3weeks to uninephrectomized rats with streptozotocin-induced diabetes. 2. Pitavastatin or spironolactone significantly reduced proteinuria and collagen deposition, and normalized creatinine clearance, serum creatinine levels and blood urea nitrogen concentrations. 3. Reverse transcription polymerase chain reaction analysis showed that the renal expression of collagenI, transforming growth factor-β and monocyte chemoattractant-1 were increased in diabetic rats and reduced by the pitavastatin and/or spironolactone treatment. 4. These agents also decreased angiotensin converting enzyme expression and aldosterone concentrations in the renal homogenate, but had no effect on blood glucose, haemoglobinA(1c) , and plasma total cholesterol, Na(+) , K(+) , aldosterone and NOx levels, or on systolic blood pressure measured by the tail-cuff method. Interestingly, cotreatment with pitavastatin and spironolactone did not result in additional normalization. 5. These results suggest that pitavastatin shows renoprotective effects against diabetic nephropathy mediated in part by inhibition of the renal RAAS, including the suppression of angiotensin-converting enzyme expression and aldosterone production.

Worsening of hyperglycemia due to atorvastatin in a renal transplant patient

New-onset diabetes mellitus post-renal transplantation [post-transplantation diabetes mellitus (PTDM)] and impaired glucose tolerance are among the most serious adverse metabolic disturbances of kidney transplants. We report a renal transplant patient whose mild post-transplant hyperglycaemia considerably worsened upon substituting atorvastatin for pravastatin. The patient was a 58-years-old Caucasian man who underwent living, non-related kidney transplantation. The mean blood sugar level (BSL) following transplantation was 113.8 mg/dl. In an attempt to reduce LDL cholesterol, atorvastatin 40 mg/day was substituted for pravastatin. Soon after commencement of atorvastatin, polydipsia and polyuria appeared. Both fasting and 2-h post-prandial BSL values increased, while there was no change in the patient's medications, dietary habits and renal function. Upon reverting back to pravastatin, BSL promptly declined to the previously mentioned baseline values. Since PTDM is a strong independent factor of graft failure, cardiovascular events and mortality, physicians should be made aware of this possible adverse effect of atorvastatin on glucose tolerance.

Reducing cardiovascular complications of type 2 diabetes by targeting multiple risk factors

Insulin resistance syndrome is characterized by hyperglycemia, atherogenic dyslipidemia, hypertension, and abdominal obesity. Hyperglycemia is the major risk factor for microvascular complications in type 2 diabetes. However, 70% to 80% of patients with type 2 diabetes will die of macrovascular disease. Atherogenic dyslipidemia-characterized by elevated triglyceride levels, low high-density lipoprotein cholesterol (HDL-c) levels, and a preponderance of small, dense, low-density lipoprotein (LDL) particles-is the major cause of atherosclerosis in individuals with type 2 diabetes. Therefore, treatment of type 2 diabetes must address hyperglycemia to prevent microvascular disease (retinopathy, neuropathy, and nephropathy) and atherogenic dyslipidemia to prevent macrovascular complications. Emerging evidence indicates lipid and glucose homeostasis are interrelated via bile acid-activated nuclear hormone receptor signaling pathways. Agents that act on these pathways could simultaneously address hyperglycemia and dyslipidemia in patients with type 2 diabetes. Recent studies have shown that bile acid sequestrants, including cholestyramine, colestimide, and colesevelam HCl, significantly improve glycemic control and reduce LDL cholesterol levels in patients with type 2 diabetes. This paper will review the effects of bile acid sequestrants on both glucose and lipid metabolism in patients with type 2 diabetes.

Effects of statins on adipose tissue inflammation: their inhibitory effect on MyD88-independent IRF3/IFN-beta pathway in macrophages

OBJECTIVE

Macrophage-mediated chronic inflammation of adipose tissue is causally linked to insulin resistance in obesity. The beneficial effects of 3-hydroxy-3-methylglutaryl (HMG) coenzyme A (CoA) reductase inhibitors (statins) on glucose metabolism have been suggested, but the effects of these agents on adipose tissue inflammation are unclear. The aim of the present study is to define the effects of statins on adipose tissue inflammation and macrophages.

METHODS AND RESULTS

Pravastatin or pitavastatin treatment of obese mice attenuated an increase in mRNA expressions of proinflammatory genes, including MCP1 and IL6, in adipose tissue. The supernatant of TLR4-stimulated RAW264 macrophages strongly induced the expression of these genes in 3T3-L1 adipocytes, which was inhibited by pretreatment of macrophages with either statin. Statins inhibited TLR4-mediated activation of interferon (IFN) regulatory factor (IRF)3 by either lipopolysaccharide (LPS) or palmitic acid, resulting in suppression of IFN-beta expression, but not that of NF-kappaB or JNK. Moreover, statins strongly downregulated TLR3-mediated gene expressions by poly(I:C), but not TLR2-stimulation by zymosan A. Neutralization of IFN-beta attenuated proinflammatory activities of the macrophage supernatant.

CONCLUSIONS

Statins partially attenuated the development of adipose tissue inflammation in obese mice, which might be associated with an inhibitory effect of statins on TLR4-triggered expression of IFN-beta via MyD88-independent signaling pathway in macrophages.

Effect of pravastatin on the development of diabetes and adiponectin production

In the West of Scotland Coronary Prevention Study (WOSCOPS), treatment of hypercholesterolemic men with pravastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, reduced their likelihood to progress to diabetes mellitus by 30%. However, the mechanism of this effect of pravastatin has not been investigated. In the current study, we examined the effect of pravastatin on the development of diabetes in obese diabetic mice, and on the insulin-induced glucose uptake and adiponectin production. Pravastatin treatment attenuated the development of diabetes in db/db and high fat/high sucrose diet-fed C57BL/6J mice. An in vivo glucose transport assay showed that pravastatin upregulated glucose uptake in adipose tissue. Insulin-stimulated glucose uptake was enhanced in primary adipocytes isolated from pravastatin-treated mice. Pravastatin treatment increased adiponectin production in 3T3-L1 adipocytes. Plasma adiponectin levels were significantly increased in pravastatin-treated mice. Analyses of plasma samples from the WOSCOPS biobank indicated a significant increase of plasma adiponectin levels with pravastatin treatment (placebo -0.28+/-0.34 microg/ml versus pravastatin +1.47+/-0.33 microg/ml, p=0.0003). Taken together, our findings suggest that pravastatin may have beneficial effects on adipose tissue, which may partly explain the reduction of the development of diabetes by pravastatin treatment.

Activation of peroxisome proliferator-activated receptor-γ (PPAR-γ) by atorvastatin is mediated by 15-deoxy-delta-12,14-PGJ2

Several studies suggested that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) activate peroxisome proliferator-activated receptor-gamma (PPAR-gamma). Atorvastatin (ATV) increases myocardial levels of prostaglandins (PG) by upregulating and activating cytosolic-phospholipase-A(2) and cycloxygenase-2 (COX2). We investigated whether ATV activates PPAR-gamma via 15-deoxy-delta-12,14-PGJ(2) (15DPGJ(2)) an endogenous ligand of PPAR-gamma and a product of PGD(2), and to compare the effects of pioglitazone (PIO), a known direct PPAR-gamma activator, to that of ATV. First we measured myocardial 15DPGJ(2) levels in the rat heart after a 3-day pretreatment with oral ATV (10 mg/(kg d)), PIO (10 mg/(kg d)), ATV+PIO, ATV+COX1 inhibitor, and ATV+COX2 inhibitor. We also assessed in human umbilical venous endothelial cells (HUVEC) whether ATV and PIO activate PPAR-gamma via 15DPGJ(2) using siRNA targeted to PGD(2) synthase. Both 15DPGJ(2) levels and PPAR-gamma activation were assessed. ATV and PIO increased myocardial 15DPGJ(2) levels in the rat myocardium and HUVEC. siRNA inhibited this increase in both groups. Both ATV and PIO augmented PPAR-gamma activation while co-treatment with siRNA completely blocked the ATV effect but only partially inhibited the PIO effect. In conclusion, both ATV and PIO activate PPAR-gamma and increase myocardial 15DPGJ(2) levels. Activation of PPAR-gamma by ATV is mediated solely by 15DPGJ(2), whereas PIO activates PPAR-gamma both directly and indirectly via 15DPGJ(2).

Effect of colestimide therapy for glycemic control in type 2 diabetes mellitus with hypercholesterolemia

Colestimide is a new anion-exchange resin used to lower serum cholesterol in Japan. Because of its excellent compliance, colestimide can replace cholestyramine. To clarify the effect of colestimide on glycemic controls, colestimide (3 g/day) or pravastatin (10 mg) was given orally to patients with type 2 diabetes treated with oral hypoglycemic agents or insulin who had low-density lipoprotein (LDL) cholesterol levels exceeding 3.6 mmol/l. In the colestimide groups, fasting plasma glucose concentrations had decreased significantly from 8.5 +/- 1.4 to 7.7 +/- 1.5 mmol/l at 3 months (P<0.05), as had glycated hemoglobin (HbA1c) from 7.7 +/- 0.7% to 6.8 +/- 0.5%, for an 8% reduction (P<0.01). Fasting plasma glucose and HbA1c did not change in the pravastatin group. Total cholesterol and LDL-cholesterol decreased significantly (P<0.01) with either medication, with similar reduction rates for both drugs. Doses of oral hypoglycemic agents and insulin did not change during the study, and body weight remained stable. Considering that patients with type 2 diabetes often have hyperlipidemia, colestimide therapy may have a clinically useful dual action in such patients.

Statins: beneficial or adverse for glucose metabolism

Large-scale clinical trials have established that statin use for lowering blood cholesterol is beneficial in reducing atherosclerotic cardiovascular diseases in different populations. However, the general reputation of statins seems to be clouded by a potential adverse effect of a class of statins on glucose metabolism. This paper reviewed clinical data of statins regarding the effects on diabetes mellitus and glucose metabolism. At least five randomized controlled studies, primarily investigating the protective effect of statins on the risk of cardiovascular diseases, have addressed the effect of statins on glucose metabolism in Western countries. One study showed that pravastatin (40 mg/day) was protective against the development of diabetes mellitus. Two studies of atorvastatin (10 mg/day) and one study of simvastatin (40 mg/day) showed no measurable effect of these regimens on the risk of diabetes mellitus or the clinical course of diabetes mellitus. One study of atorvastatin (80 mg/day) versus pravastatin (40 mg/day) suggested a deterioration of glucose metabolism associated with a high dose of atorvastatin. In Japan, a few case reports have noted a potential adverse effect of atorvastatin on glycemic control in patients with diabetes mellitus; however, seven clinical trials have showed no such effect of atorvastatin although these studies were relatively small in size and short in follow-up. Only one of the two observational studies suggested a possible adverse effect of atorvastatin on glycemic control. Evidence is extremely limited regarding atorvastatin use and deterioration in glycemic control, and further studies are needed to draw a conclusion on this issue.

The effect of fluvastatin on plasma adiponectin levels in dyslipidaemia

OBJECTIVE

There is controversy about the effects of statins on insulin resistance and plasma adiponectin. The aim of this study was to investigate the effects of fluvastatin treatment on these parameters in a group of dyslipidaemic patients who had no confounding factors for insulin resistance or alterations in plasma adiponectin.

DESIGN AND PATIENTS

Forty-nine patients [27 males, 22 females; mean age 47.2 +/- 10.3 years; body mass index (BMI) 29.64 +/- 3.2 kg/m2] with dyslipidaemia and 20 controls (six males, 14 females; mean age 45.3 +/- 9.31 years; BMI 30.07 +/- 4.04 kg/m2) were enrolled. All patients were treated initially with therapeutic lifestyle changes (TLC) for 6 weeks. Six out of 49 subjects were excluded from the study. Then, 24 out of 43 patients with high blood cholesterol despite TLC were allocated to fluvastatin 80 mg daily plus TLC, and the remaining 19 patients with normal cholesterol were subjected to TLC alone for additional 12 weeks.

MEASUREMENTS

Plasma adiponectin, immunoreactive insulin levels, BMI, waist circumference, blood pressure, lipids, and glucose were determined. The insulin sensitivity index was quantified using the homeostasis model assessment (HOMA).

RESULTS

TLC caused significant improvement in plasma insulin (P = 0.02) and elevation in plasma adiponectin (P = 0.02). Fluvastatin treatment decreased total cholesterol and low density lipoprotein (LDL)-cholesterol significantly (P = 0.01 and P = 0.02, respectively). No significant effect of fluvastatin was observed on plasma insulin or adiponectin or on the HOMA index.

CONCLUSIONS

Fluvastatin does not improve plasma adiponectin levels and insulin sensitivity, despite its beneficial effects on lipid levels. Our data, however, were limited by the fact that a more accurate method of assessing insulin sensitivity, the euglycaemic-hyperinsulinaemic glucose clamp technique, was not used.