Homocysteine, reactive oxygen species and nitric oxide in type 2 diabetes mellitus

2007 ◽  
Vol 120 (4) ◽  
pp. 607-613 ◽  
Author(s):  
M.G. Signorello ◽  
G.L. Viviani ◽  
U. Armani ◽  
R. Cerone ◽  
G. Minniti ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Diabetes Mellitus ◽  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Reactive Oxygen ◽  
Oxygen Species

scholarly journals Reactive Oxygen Species Modulator-1 (ROMO-1) Polymorphism Rs6060566 and The Risk of Myocardial Infarction in Slovenian Subjects With Type 2 Diabetes Mellitus

2020 ◽  
Author(s):  
Miha Tibaut ◽  
Sara Mankoč Ramuš ◽  
Daniel Petrovič
Keyword(s):  
Diabetes Mellitus ◽  
Myocardial Infarction ◽  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Coronary Artery ◽  
Coronary Arteries ◽  
Reactive Oxygen ◽  
Oxygen Species

Abstract Background We aimed to examine the role of the rs6060566 polymorphism of the reactive oxygen species modulator-1 (ROMO-1) gene in the development of myocardial infarction (MI) in Caucasians with type 2 diabetes mellitus (T2DM). Methods A total of 1072 subjects with T2DM were enrolled in cross-sectional case-control study: 335 subjects with MI and 737 subjects without clinical signs of coronary artery disease (CAD). Genetic analysis of the rs6060566 polymorphism was performed in all subjects. To assess the degree of coronary artery obstruction, a subpopulation of 128 subjects with T2DM underwent coronary computed tomography (CT) angiography. Next, endarterectomy samples were obtained during myocardial revascularization from diffusely diseased coronary arteries in 40 cases, which were analysed for ROMO-1 expression according to their genotype. Results There were no statistically significant associations between different genotypes or alleles of the rs6060566 polymorphism and MI in subjects with T2DM. The carriers of the C allele of the ROMO-1 rs6060566 had a threefold increased likelihood of having coronary artery stenosis (AOR = 3.27, 95% CI 1.16–9.20). Furthermore, the carriers of the C allele showed higher number of positive cells for ROMO-1 expression in endarterectomy samples of coronary arteries. Conclusions In accordance to our study, the rs6060566 polymorphism of the ROMO-1 gene is not the risk factor for MI in Caucasians with T2DM. However, we found that subjects carrying the C allele were at a 3.27-fold increased risk of developing severe CAD compared with those who had nonobstructive CAD. Moreover, The C allele carriers showed statistically higher number of cells positive for ROMO-1 compared with T allele carriers in coronary endarterectomy samples.

scholarly journals Effects of prolonged type 2 diabetes on mitochondrial function in cerebral blood vessels

2019 ◽  
Vol 317 (5) ◽  
pp. H1086-H1092 ◽  
Author(s):  
Ivan Merdzo ◽  
Ibolya Rutkai ◽  
Venkata N. L. R. Sure ◽  
Prasad V. G. Katakam ◽  
David W. Busija
Keyword(s):  
Diabetes Mellitus ◽  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Type 2 Diabetes Mellitus ◽  
Mitochondrial Function ◽  
Mitochondrial Respiration ◽  
Ros Production ◽  
Oxygen Species ◽  
Cerebral Blood Vessels

One of the major characteristics of hyperglycemic states such as type 2 diabetes is increased reactive oxygen species (ROS) generation. Since mitochondria are a major source of ROS, it is vital to understand the involvement of these organelles in the pathogenesis of ROS-mediated conditions. Therefore, we investigated mitochondrial function and ROS production in cerebral blood vessels of 21-wk-old Zucker diabetic fatty obese rats and their lean controls. We have previously shown that in the early stages of insulin resistance, and short periods of type 2 diabetes mellitus, only mild differences exist in mitochondrial function. In the present study, we examined mitochondrial respiration, mitochondrial protein expression, and ROS production in large-surface cerebral arteries. We used 21-wk-old animals exposed to peak glucose levels for 7 wk and compared them with our previous studies on younger diabetic animals. We found that the same segments of mitochondrial respiration (basal respiration and proton leak) were diminished in diabetic groups as they were in younger diabetic animals. Levels of rattin, a rat humanin analog, tended to decrease in the diabetic group but did not reach statistical significance ( P = 0.08). Other mitochondrial proteins were unaffected, which might indicate the existence of compensatory mechanisms with extension of this relatively mild form of diabetes. Superoxide levels were significantly higher in large cerebral vessels of diabetic animals compared with the control group. In conclusion, prolonged dietary diabetes leads to stabilization, rather than deterioration, of metabolic status in the cerebral circulation, despite continued overproduction of ROS. NEW & NOTEWORTHY We have characterized for the first time the dynamics of mitochondrial function during the progression of type 2 diabetes mellitus with regard to mitochondrial respiration, protein expression, and reactive oxygen species production. In addition, this is the first measurement of rattin levels in the cerebral vasculature, which could potentially lead to novel treatment options.

Accelerated endothelial dysfunction in mild prediabetic insulin resistance: the early role of reactive oxygen species

2007 ◽  
Vol 293 (5) ◽  
pp. E1311-E1319 ◽  
Author(s):  
Edward R. Duncan ◽  
Simon J. Walker ◽  
Vivienne A. Ezzat ◽  
Stephen B. Wheatcroft ◽  
Jian-Mei Li ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Insulin Resistance ◽  
Reactive Oxygen Species ◽  
Type 2 Diabetes ◽  
Endothelial Dysfunction ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Wild Type

Insulin resistance is well established as an independent risk factor for the development of type 2 diabetes and cardiovascular atherosclerosis. Most studies have examined atherogenesis in models of severe insulin resistance or diabetes. However, by the time of diagnosis, individuals with type 2 diabetes already demonstrate a significant atheroma burden. Furthermore, recent studies suggest that, even in adolescence, insulin resistance is a progressive disorder that increases cardiovascular risk. In the present report, we studied early mechanisms of reduction in the bioavailability of the antiatheroscerotic molecule nitric oxide (NO) in very mild insulin resistance. Mice with haploinsufficiency for the insulin receptor (IRKO) are a model of mild insulin resistance with preserved glycemic control. We previously demonstrated that 2-mo-old (Young) IRKO mice have preserved vasorelaxation responses to ACh. This remained the case at 4 mo of age. However, by 6 mo, despite no significant deterioration in glucose homeostasis (Adult), IRKO mice had marked blunting of ACh-mediated vasorelaxation [IRKO maximum contraction response (Emax) 66 ± 5% vs. wild type 87 ± 4%, P < 0.01]. Despite the endothelial dysfunction demonstrated, aortic endothelial nitric oxide synthase (eNOS) mRNA levels were similar in Adult IRKO and wild-type mice, and, interestingly, aortic eNOS protein levels were increased, suggesting a compensatory upregulation in the IRKO. We then examined the potential role of reactive oxygen species in mediating early endothelial dysfunction. The superoxide dismutase mimetic Mn(III)tetrakis(1-methyl-4-pyridyl) porphyrin pentachloride (MnTMPyP) restored ACh relaxation responses in the Adult IRKO (Emax to ACh with MnTMPyP 85 ± 5%). Dihydroethidium fluorescence of aortas and isolated coronary microvascular endothelial cells confirmed a substantial increase in endothelium-derived reactive oxygen species in IRKO mice. These data demonstrate that mild insulin resistance is a potent substrate for accelerated endothelial dysfunction and support a role for endothelial cell superoxide production as a mechanism underlying the early reduction in NO bioavailability.

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