Statins and new-onset diabetes in primary prevention setting: an updated meta-analysis stratified by baseline diabetes risk

AIMS

The use of statins has been associated with an increased risk of new-onset diabetes. The characteristics of the population could influence this association. The objective of this study was to determine the risk of new-onset diabetes with the use of statins in patients in primary prevention, with an assessment of the results according to the baseline risk of developing diabetes of the included population.

METHODS

We performed an updated meta-analysis including randomized trials of statin therapy in primary prevention settings that report new-onset diabetes. The rate of new cases of diabetes in the control arms was estimated for each study. The studies were classified into two groups (low rate: < 7.5 events per 1000 patients-year; high rate; ≥ 7.5 events per 1000 patients-year). The fixed-effects model was performed.

RESULTS

Eight studies (70,453 patients) were included. Globally, statin therapy was associated with an increased risk of new-onset diabetes (OR 1.1; 95% CI 1.0-1.2, I2 35%). When we analyzed the studies according to the baseline diabetes risk in the control groups, the results showed that there was a greater risk only in the studies with a high baseline rate (OR 1.2; 95% CI 1.1-1.3, I2 0%; interaction p value = 0.01).

CONCLUSION

Globally, the use of statins in patients in primary prevention was associated with an increased risk of new-onset diabetes. In the stratified analysis, this association was observed only in the group of studies with a high baseline rate of events.

Cardiac extracellular matrix modulation in a rat-diabetic model: biochemical and anti-oxidant beneficial effect of pomegranate (Punica granatum) peel extract

CONTEXT

Disorders associated with diabetes and the beneficial effects of pomegranate peel extract (PPE) were widely reported. However effect of diabetes and PPE on extracellular matrix (ECM) remodelling needs further investigation.

OBJECTIVES

The focus of this study was to investigate the involvement of diabetes in cardiac ECM and the beneficial effects of PPE.

METHODS

Diabetes was induced by alloxan. PPE group was injected with 100 mg/kg of PPE. The phenolic profile of PPE was analyzed by HPLC. ECM was detected by ELISA. MMP-1, -8, -13 were determined by a colorimetric assay.

RESULTS

Compared to control fibronectin and laminin plasma content was higher respectively by 69% and 42% (p < 0.05) in diabetes. LV content of hydroxyproline and total collagen was higher by 195% (p < 0.01) and 56% (p < 0.05) in the diabetic group compared to control and restored at a similar level to controls in the PPE group. Compared to control, collagenase activity was significantly reduced by 32% (p < 0.05) and 35% (p < 0.05) respectively in ALX and PPF groups. There is no significant difference in collagenase activities in diabetic rats after and before PPE injection.

CONCLUSION

Diabetes is involved in cardiac ECM remodelling which can be improved by PPE. These findings will be useful for more understanding diabetes-induced cardiac disorders.

The influence of high-density lipoprotein (HDL) and HDL subfractions on insulin secretion and cholesterol efflux in pancreatic derived β-cells

BACKGROUND

High-density lipoprotein (HDL) is considered a complex plasma-circulating particle with subfractions that vary in function, size, and chemical composition. We sought to test the effects of HDL, and HDL subfractions on insulin secretion and cholesterol efflux in the β-cell line MIN-6.

METHODS

We used total HDL and HDL subfractions 2a, 2b, 3a, 3b, and 3c, isolated from human plasma, to test insulin secretion under different glucose concentrations as well as insulin content and cholesterol efflux in the insulinoma MIN-6 cell line.

RESULTS

Incubation of MIN-6 cells with low glucose and total HDL increased insulin release two-fold. Meanwhile, when high glucose and HDL were used, insulin release increased more than five times. HDL subfractions 2a, 2b, 3a, 3b, and 3c elicited higher insulin secretion and cholesterol efflux than their respective controls, at both low and high glucose concentrations. The insulin content of the MIN-6 cells incubated with low glucose and any of the five HDL subclasses had a modest reduction compared with their controls. However, there were no statistically significant differences between each HDL subfraction on their capacity of eliciting insulin secretion, insulin content, or cholesterol efflux.

CONCLUSIONS

HDL can trigger insulin secretion under low, normal, and high glucose conditions. We found that all HDL subfractions exhibit very similar capacity to increase insulin secretion and cholesterol efflux. This is the first report demonstrating that HDL subfractions act both as insulin secretagogues (under low glucose) and insulin secretion enhancers (under high glucose) in the MIN-6 cell line.

E17241 as a Novel ABCA1 (ATP-Binding Cassette Transporter A1) Upregulator Ameliorates Atherosclerosis in Mice

[Figure: see text].

Therapy with cholesteryl ester transfer protein (CETP) inhibitors and diabetes risk

BACKGROUND

Cholesteryl ester transfer protein (CETP) inhibitors are a class of drugs that targets the CETP enzyme to significantly increase serum high-density lipoprotein cholesterol (HDL-C) and decrease low-density lipoprotein cholesterol (LDL-C) levels. As HDL-C has potential antidiabetic properties, and the beneficial effects of CETP drugs on glucose homoeostasis have not been sufficiently studied, the aims of this study were: (1) to evaluate the effect of CETP inhibitors on the incidence of diabetes; and (2) to assess the association between CETP inhibitor-induced changes in HDL-C levels and incidence of diabetes.

METHODS

A meta-analysis was performed of randomized controlled clinical trials of CETP inhibitor therapy, either alone or combined with other lipid-lowering drugs, reporting data from new cases of diabetes with a minimum of 6 months of follow-up, after searching the PubMed/MEDLINE, Embase and Cochrane Controlled Trials databases. A fixed-effects meta-regression model was then applied.

RESULTS

Four eligible trials of CETP inhibitors, involving a total of 73,479 patients, were considered for the analyses, including 960 newly diagnosed cases of diabetes in the CTEP inhibitor group vs 1086 in the placebo group. CETP inhibitor therapy was associated with a significant 12% reduction in incidence of diabetes (OR: 0.88, 95% CI: 0.81-0.96; P=0.005). Assessment of the relationship between on-treatment HDL-C and the effect of CETP inhibitors showed a statistically non-significant trend (Z=-1.13, P=0.26).

CONCLUSION

CETP inhibitors reduced the incidence of diabetes. The improvement in glucose metabolism may have been related, at least in part, to the increase in HDL-C concentration.

Expanding roles of ABCG1 and sterol transport

PURPOSE OF REVIEW

To offer a comprehensive review on the role of ABCG1 in cellular sterol homeostasis.

RECENT FINDINGS

Early studies with Abcg1 mice indicated that ABCG1 was crucial for tissue lipid homeostasis, especially in the lung. More recent studies have demonstrated that loss of ABCG1 has wide-ranging consequences and impacts lymphocyte and stem cell proliferation, endothelial cell function, macrophage foam cell formation, as well as insulin secretion from pancreatic β cells. Recent studies have also demonstrated that ABCG1 functions as an intracellular lipid transporter, localizes to intracellular vesicles/endosomes, and that the transmembrane domains are sufficient for localization and transport function.

SUMMARY

ABCG1 plays a crucial role in maintaining intracellular sterol and lipid homeostasis. Loss of this transporter has significant, cell-type-specific consequences ranging from effects on cellular proliferation, to surfactant production and/or insulin secretion. Elucidation of the mechanisms by which ABCG1 affects intracellular sterol flux/movement should provide important information that may link ABCG1 to diseases of dysregulated tissue lipid homeostasis.

Serum CA19-9 level associated with metabolic control and pancreatic beta cell function in diabetic patients

CA19-9 is a tumor-associated antigen. It is also a marker of pancreatic tissue damage that might be caused by diabetes. Long-term poor glycemic control may lead to pancreatic beta cell dysfunction which is reflected by elevated serum CA19-9 level. Intracellular cholesterol accumulation leads to islet dysfunction and impaired insulin secretion which provide a new lipotoxic model. This study firstly found total cholesterol was one of the independent contributors to CA19-9. Elevated serum CA19-9 level in diabetic patients may indicate further investigations of glycemic control, pancreatic beta cell function, and total cholesterol level.