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Full-Text Articles in Medicinal and Pharmaceutical Chemistry

Reactive Oxygen Species Modulation Of Na/K-Atpase Regulates Fibrosis And Renal Proximal Tubular Sodium Handling, Jiang Liu, David J. Kennedy, Yanling Yan, Joseph I. Shapiro Md Oct 2015

Reactive Oxygen Species Modulation Of Na/K-Atpase Regulates Fibrosis And Renal Proximal Tubular Sodium Handling, Jiang Liu, David J. Kennedy, Yanling Yan, Joseph I. Shapiro Md

Joseph I Shapiro MD

The Na/K-ATPase is the primary force regulating renal sodium handling and plays a key role in both ion homeostasis and blood pressure regulation. Recently, cardiotonic steroids (CTS)-mediated Na/K-ATPase signaling has been shown to regulate fibrosis, renal proximal tubule (RPT) sodium reabsorption, and experimental Dahl salt-sensitive hypertension in response to a high-salt diet. Reactive oxygen species (ROS) are an important modulator of nephron ion transport. As there is limited knowledge regarding the role of ROS-mediated fibrosis and RPT sodium reabsorption through the Na/K-ATPase, the focus of this review is to examine the possible role of ROS in the regulation of Na/K-ATPase …


Ho-1 Upregulation Attenuates Adipocyte Dysfunction, Obesity, And Isoprostane Levels In Mice Fed High Fructose Diets, Zeid Khitan, Mohit Harsh, Komal Sodhi, Joseph I. Shapiro Md, Nader G. Abraham Jul 2015

Ho-1 Upregulation Attenuates Adipocyte Dysfunction, Obesity, And Isoprostane Levels In Mice Fed High Fructose Diets, Zeid Khitan, Mohit Harsh, Komal Sodhi, Joseph I. Shapiro Md, Nader G. Abraham

Joseph I Shapiro MD

Background. Fructose metabolism is an unregulated metabolic pathway and excessive fructose consumption is known to activate ROS.HO-1 is a potent antioxidant gene that plays a key role in decreasing ROS and isoprostanes.We examinedwhether the fructosemediated increase in adipocyte dysfunction involves an increase in isoprostanes and that pharmacological induction ofHO-1would decrease both isoprostane levels and adipogenesis. Methods and Results. We examined the effect of fructose, on adipogenesis in human MSCs in the presence and absence of CoPP, an inducer of HO-1. Fructose increased adipogenesis and the number of large lipid droplets while decreasing the number of small lipid droplets (𝑃 < 0.05). …


Intracellular Reactive Oxygen Species Mediate The Linkage Of Na+/K+-Atpase To Hypertrophy And Its Marker Genes In Cardiac Myocytes, Joseph I. Shapiro, Amir Askari, Zijian Xie, Peter Kometiani, Jie Li, Jiang Liu Mar 2015

Intracellular Reactive Oxygen Species Mediate The Linkage Of Na+/K+-Atpase To Hypertrophy And Its Marker Genes In Cardiac Myocytes, Joseph I. Shapiro, Amir Askari, Zijian Xie, Peter Kometiani, Jie Li, Jiang Liu

Joseph I Shapiro MD

We showed before that in cardiac myocytes partial inhibition of Na+/K+-ATPase by nontoxic concentrations of ouabain causes hypertrophy and transcriptional regulations of growth-related marker genes through multiple Ca2+-dependent signal pathways many of which involve Ras and p42/44 mitogen-activated protein kinases. The aim of this work was to explore the roles of intracellular reactive oxygen species (ROS) in these ouabain-initiated pathways. Ouabain caused a rapid generation of ROS within the myocytes that was prevented by preexposure of cells to N-acetylcysteine (NAC) or vitamin E. These antioxidants also blocked or attenuated the following actions of ouabain: inductions of the genes of skeletal …


Ouabain Interaction With Cardiac Na+/K+-Atpase Initiates Signal Cascades Independent Of Changes In Intracellular Na+ And Ca2+, Jiang Liu, Jiang Tian, Michael Haas, Joseph I. Shapiro, Amir Askari, Zijian Xie Mar 2015

Ouabain Interaction With Cardiac Na+/K+-Atpase Initiates Signal Cascades Independent Of Changes In Intracellular Na+ And Ca2+, Jiang Liu, Jiang Tian, Michael Haas, Joseph I. Shapiro, Amir Askari, Zijian Xie

Joseph I Shapiro MD

We have shown previously that partial inhibition of the cardiac myocyte Na+/K+-ATPase activates signal pathways that regulate myocyte growth and growth-related genes and that increases in intracellular Ca2+ concentration ([Ca2+]i) and reactive oxygen species (ROS) are two essential second messengers within these pathways. The aim of this work was to explore the relation between [Ca2+]i and ROS. When myocytes were in a Ca2+-free medium, ouabain caused no change in [Ca2+]i, but it increased ROS as it did when the cells were in a Ca2+-containing medium. Ouabain-induced increase in ROS also occurred under conditions where there was little or no change …