Effects of a sucrose‐enriched diet on the pattern of gene expression, contraction and Ca2+ transport in Goto–Kakizaki type 2 diabetic rat heart. Issue 6 (6th May 2014)

• Record Type: Journal Article
• Authors: Gaber, E. M.; Jayaprakash, P.; Qureshi, M. A.; Parekh, K.; Oz, M.; Adrian, T. E.; Howarth, F. C.
• Is Part Of: Experimental physiology. Volume 99:Issue 6(2014:Jun.)
• Page Start: 881
• Page End: 893
• Publication Date: 2014-05-06
• Subjects: Physiology, Experimental -- Periodicals; 571.0724
• DOI: 10.1113/expphysiol.2013.077594
• Languages: English
• ISSNs: 0958-0670

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="eph1444-sec-0010" sec-type="section"> <title>New Findings</title> <p> <list id="eph1444-list-0001" list-type="bullet"> <list-item> <p> <bold>What is the central question of this study?</bold> </p> <p>Poor diet is a risk factor for development of type 2 diabetes mellitus and its associated complications. In this study, the effects of sucrose‐enriched diet on the pattern of gene expression, contraction and Ca<sup>2+</sup> transport in type 2 diabetic heart are explored.</p> </list-item> <list-item> <p> <bold>What is the main finding and its importance?</bold> </p> <p>The altered pattern of gene expression in type 2 diabetic hearts was further altered in diabetic and control rats that received a sucrose‐enriched diet, and these alterations were associated with changes in ventricular myocyte shortening and Ca<sup>2+</sup> transport.</p> </list-item> </list> </p> </sec> <sec id="eph1444-sec-0020" sec-type="section"> <p>There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus (T2DM), and cardiovascular disease is the major cause of morbidity and mortality in diabetic patients. A variety of diastolic and systolic dysfunctions have been demonstrated in type 2 diabetic heart. The consumption of sugar‐sweetened beverages has been linked to rising rates of obesity, which in turn is a risk factor for development of T2DM. In this study, the effects of a sucrose‐enriched diet on the pattern of gene expression, contraction and Ca<sup>2+</sup> transport in the Goto–Kakizaki T2DM rat heart were investigated. Genes encoding cardiac muscle proteins (<italic>Myh7</italic>, <italic>Mybpc3</italic>, <italic>Myl1</italic>, <italic>Myl3</italic> and <italic>Mylpf</italic>), intercellular proteins (<italic>Gja4</italic>), cell membrane transport (<italic>Atp1b1</italic>), calcium channels (<italic>Cacna1c</italic>, <italic>Cacna1g</italic> and <italic>Cacnb1</italic>) and potassium channels (<italic>Kcnj11</italic>) were upregulated and genes encoding potassium channels (<italic>Kcnb1</italic>) were downregulated in GK compared with control rats. Genes encoding cardiac muscle proteins (<italic>Myh6</italic>, <italic>Mybpc3</italic> and <italic>Tnn2</italic>), intercellular proteins (<italic>Gja1</italic> and <italic>Gja4</italic>), intracellular Ca<sup>2+</sup> transport (<italic>Atp2a1</italic> and <italic>Ryr2</italic>), cell membrane transport (<italic>Atp1a2</italic> and <italic>Atp1b1</italic>) and potassium channel proteins (<italic>Kcnj2</italic> and <italic>Kcnj8</italic>) were upregulated and genes encoding cardiac muscle proteins (<italic>Myh7</italic>) were downregulated in control rats fed sucrose compared with control rats. Genes encoding cardiac muscle proteins (<italic>Myh7</italic>) and potassium channel proteins (<italic>Kcnj11</italic>) were downregulated in control and GK rats fed sucrose compared with control and GK rats, respectively. The amplitude of shortening was reduced in myocytes from the control–sucrose group compared with control rats and in the GK–sucrose group compared with GK rats. The amplitude of the Ca<sup>2+</sup> transient was increased in myocytes from control–sucrose compared with control rats and decreased in GK–sucrose compared with GK rats. Subtle alterations in the pattern of expression of genes encoding a variety of cardiac muscle proteins are associated with changes in shortening and intracellular Ca<sup>2+</sup> transport in ventricular myocytes from GK T2DM and control rats fed a sucrose‐enriched diet.</p> </sec> </abstract>