Novel CoQ10 antidiabetic mechanisms underlie its positive effect: modulation of insulin and adiponectine receptors, Tyrosine kinase, PI3K, glucose transporters, sRAGE and visfatin in insulin resistant/diabetic rats

The effects of coenzyme Q10 administration on glucose homeostasis parameters, lipid profiles, biomarkers of inflammation and oxidative stress in patients with metabolic syndrome

BACKGROUND

Limited data are available indicating the effects of coenzyme Q10 (CoQ10) supplementation on metabolic status of patients with metabolic syndrome (MetS).

PURPOSE

The present study was conducted to determine the effects of CoQ10 administration on glucose homeostasis parameters, lipid profiles, biomarkers of inflammation and oxidative stress among patients with MetS.

METHODS

This randomized, double-blind, placebo-controlled trial was performed among 60 overweight or obese and type 2 diabetes mellitus patients with coronary heart disease aged 40-85 years old. Participants were randomly allocated into two groups. Group A (n = 30) received 100 mg CoQ10 supplements and group B (n = 30) received placebo for 8 weeks. Fasting blood samples were taken at the beginning of the study and after 8-week intervention to quantify glucose homeostasis parameters, lipid profiles and biomarkers of inflammation and oxidative stress.

RESULTS

Compared with the placebo, CoQ10 supplementation resulted in a significant reduction in serum insulin levels (-2.1 ± 7.1 vs. +4.1 ± 7.8 µIU/mL, P = 0.002) and homeostasis model of assessment-insulin resistance (-0.7 ± 2.1 vs. +1.0 ± 2.0, P = 0.002) and homeostatic model assessment-beta cell function (-5.9 ± 22.2 vs. +15.9 ± 34.0, P = 0.005). In addition, patients who received CoQ10 supplements had a significant increase in plasma total antioxidant capacity (TAC) concentrations (+26.0 ± 105.0 vs. -162.2 ± 361.8 mmol/L, P = 0.008) compared with the placebo group. However, after adjustment for the baseline levels, age and baseline BMI, the effect on TAC levels (P = 0.08) disappeared. Additionally, compared with the placebo group, a significant positive trends in plasma glutathione (P = 0.06) and a significant reduction in malondialdehyde (P = 0.08) were seen among patients who received CoQ10 supplement. We did not observe any significant changes in fasting plasma glucose, lipid concentrations and inflammatory markers.

CONCLUSIONS

Overall, daily intake of 100 mg CoQ10 supplements among patients with MetS for 8 weeks had beneficial effects on serum insulin levels, HOMA-IR, HOMA-B and plasma TAC concentrations.

CLINICAL TRIAL REGISTRATION NUMBER

www.irct.ir : IRCT201502245623N35.

New animal models reveal that coenzyme Q2 (Coq2) and placenta-specific 8 (Plac8) are candidate genes for the onset of type 2 diabetes associated with obesity in rats

Obesity is a major risk factor for the onset of type 2 diabetes; however, little is known about the gene(s) involved. Therefore, we developed new animal models of obesity to search for diabetogenic genes associated with obesity. We generated double congenic rat strains with a hyperglycaemic quantitative trait locus (QTL) derived from the Otsuka Long-Evans Tokushima Fatty rat and a fa/fa (Lepr-/-) locus derived from the Zucker Fatty rat; phenotypic analysis for plasma glucose and insulin levels and RNA and protein levels were determined using reverse transcription quantitative PCR and Western blotting analyses, respectively. The double congenic strain F344-fa-nidd2 (Lepr-/- and Nidd2/of) exhibited significantly higher glucose levels and significantly lower hypoglycaemic response to insulin than the obese control strain F344-fa (Lepr-/-). These phenotypes were clearly observed in the obese strains but not in the lean strains. These results indicate that the Nidd2/of locus harbours a diabetogenic gene associated with obesity. We measured the expression of 60 genes in the Nidd2/of QTL region between the strains and found that the mRNA expression levels of five genes were significantly different between the strains under the condition of obesity. However, three of the five genes were differentially expressed in both obese and lean rats, indicating that these genes are not specific for the condition of obesity. Conversely, the other two genes, coenzyme Q2 (Coq2) and placenta-specific 8 (Plac8), were differentially expressed only in the obese rats, suggesting that these two genes are candidates for the onset of type 2 diabetes associated with obesity in rats.

Pathogenesis and management of the diabetogenic effect of statins: a role for adiponectin and coenzyme Q10?

There is growing evidence to suggest that statin therapy is associated with an increased risk of incident diabetes. The risk for statin-related diabetes depends upon many factors including age, pre-existing diabetic risk, type and potency of statin. Several mechanisms have been suggested for the diabetogenic effects of statins involving processes that alter islet ß-cell function, resulting in impaired glucose metabolism. Recent evidence suggests that the association of statin therapy with the development of diabetes may be partly mediated by a statin-induced decrease in circulating adiponectin and coenzyme Q10. The available evidence suggests the benefit of statins in reducing cardiovascular events outweigh the risk of developing diabetes. Moreover, statin therapy does not impair glycemic control in diabetic patients. Expert recommendations for the use of statins in people at risk of developing diabetes have recently been published. However, further research is required to elucidate both the association between statin use and incident diabetes as well as underlying mechanisms.