1,181 research outputs found

    Signaling of Reactive Oxygen and Nitrogen Species in Diabetes Mellitus

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    Disorder of physiological signaling functions of reactive oxygen species(ROS) superoxide and hydrogen peroxide and reactive nitrogen species (RNS) nitric oxide and peroxynitrite is an important feature of diabetes mellitus type 1 and type 2. It is now known that hyperglycemic conditions of cells are associated with the enhanced levels of ROS mainly generated by mitochondria and NADPH oxidase. It has been established that ROS stimulate many enzymatic cascades under normal physiological conditions, but hyperglycemia causes ROS overproduction and the deregulation of ROS signaling pathways initiating the development of diabetes mellitus. On the other hand the deregulation of RNS signaling leads basically to a decrease in NO formation with subsequent damaging disorders. In the present work we will consider the pathological changes of ROS and RNS signaling in enzyme/gene regulated processes catalyzed by protein kinases C and B (Akt/B), phosphatidylinositol 3′-kinase (PI3-kinase), extracellular signal-regulated kinase 1/2 (ERK1/2) and some others. Furthermore we will discuss a particularly important role of several ROS-regulated genes and adapter proteins such as the p66shc, FOXO3a and Sirt2. The effects of low and high ROS levels in diabetes will be also considered. Thus the regulation of damaging ROS levels in diabetes by antioxidants and free radical scavengers must be one of promising treatment of this disease, however, because of the inability of traditionalantioxidative vitamin E and C to interact with superoxide and hydrogen peroxide,new free radical scavengers such as flavonoids, quinones and synthetic mimetics of superoxide dismutase (SOD) should be intensively studied

    ROS and RNS Signaling in Heart Disorders: Could Antioxidant Treatment Be Successful?

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    There is not too much success in the antioxidant treatment of heart deceases in humans. However a new approach is now developed that suggests that depending on their structures and concentrations antioxidants can exhibit much more complicated functions in many pathological disorders. It is now well established that physiological free radicals superoxide and nitric oxide together with their derivatives hydrogen peroxide and peroxynitrite (all are named reactive oxygen species (ROS) and reactive nitrogen species (RNS)) play a more important role in heart diseases through their signaling functions. Correspondingly this work is dedicated to the consideration of damaging signaling by ROS and RNS in various heart and vascular disorders: heart failure (congestive heart failure or CHF), left ventricular hypertrophy (LVH), coronary heart disease, cardiac arrhythmias, and so forth. It will be demonstrated that ROS overproduction (oxidative stress) is a main origin of the transformation of normal physiological signaling processes into the damaging ones. Furthermore the favorable effects of low/moderate oxidative stress through preconditioning mechanisms in ischemia/reperfusion will be considered. And in the last part we will discuss the possibility of efficient application of antioxidants and enzyme/gene inhibitors for the regulation of damaging ROS signaling in heart disorders

    Reactive oxygen species and age-related genes p66Shc, sirtuin, FoxO3 and klotho in senescence

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    Reactive oxygen species (ROS) superoxide and hydrogen peroxide perform important signaling functions in many physiological and pathophysiological processes. Cell senescence and organismal age are not exemptions. Aging-regulating genes p66shc, Sirtuin, FOXO3a and Klotho are new important factors which are stimulated by ROS signaling. It has been shown that ROS participate in initiation and prolongation of gene-dependent aging development. ROS also participate in the activation of protein kinases Akt/PKB and extracellular signal-regulated kinase ERK, which by themselves or through gene activation stimulates or retards cell senescence. Different retarding/stimulating effects of ROS might depend on the nature of signaling species—superoxide or hydrogen peroxide. Importance of radical anion superoxide as a signaling molecule with “super-nucleophilic” properties points to the possibility of the use of superoxide scavengers (SOD mimetics, ubiquinones and flavonoids) for retarding the development of aging

    Vegetative state of early-school age children with posture violence

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    Sustainable growth of number of children with violence of system (MSS) functions, which leaves with out своєчасної correction, as a result becomes the factor of development of spine structure alteration and the cause of workability decrease. Physical rehabilitation of children with functional disorder of MSS is an arduous, multidimensional task, due to the fact, that such kind of children has own distinctive features of physical, functional and psychological development. Especially, this relates to children of early-school age. The key basic destination in development of rehabilitation technology remains formation of adaptation reaction in children with posture disorder
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