TY - JOUR
T1 - Effects of exercise training on excitation-contraction coupling and related mRNA expression in hearts of Goto-Kakizaki type 2 diabetic rats
AU - Salem, K. A.
AU - Qureshi, M. A.
AU - Sydorenko, V.
AU - Parekh, K.
AU - Jayaprakash, P.
AU - Iqbal, T.
AU - Singh, J.
AU - Oz, M.
AU - Adrian, T. E.
AU - Howarth, F. C.
N1 - Funding Information:
Acknowledgments This work was supported by grants from UAE University and Emirates Foundation. Research in our laboratory is also supported by LABCO a partner of Sigma-Aldrich.
PY - 2013/8
Y1 - 2013/8
N2 - Although, several novel forms of intervention aiming at newly identified therapeutic targets are currently being developed for diabetes mellitus (DM), it is well established that physical exercise continues to be one of the most valuable forms of non-pharmacological therapy. The aim of the study was to investigate the effects of exercise training on excitation-contraction coupling and related gene expression in the Goto-Kakizaki (GK) type 2 diabetic rat heart and whether exercise is able to reverse diabetes-induced changes in excitation-contraction coupling and gene expression. Experiments were performed in GK and control rats aged 10-11 months following 2-3 months of treadmill exercise training. Shortening, [Ca2+]i and L-type Ca 2+ current were measured in ventricular myocytes with video edge detection, fluorescence photometry and whole cell patch clamp techniques, respectively. Expression of mRNA was assessed in ventricular muscle with real-time RT-PCR. Amplitude of shortening, Ca2+ transients and L-type Ca2+ current were not significantly altered in ventricular myocytes from GK sedentary compared to control sedentary rats or by exercise training. Expression of mRNA encoding Tpm2, Gja4, Atp1b1, Cacna1g, Cacnb2, Hcn2, Kcna3 and Kcne1 were up-regulated and Gja1, Kcnj2 and Kcnk3 were down-regulated in hearts of sedentary GK rats compared to sedentary controls. Gja1, Cav3 and Kcnk3 were up-regulated and Hcn2 was down-regulated in hearts of exercise trained GK compared to sedentary GK controls. Ventricular myocyte shortening and Ca 2+ transport were generally well preserved despite alterations in the profile of expression of mRNA encoding a variety of cardiac muscle proteins in the adult exercise trained GK diabetic rat heart.
AB - Although, several novel forms of intervention aiming at newly identified therapeutic targets are currently being developed for diabetes mellitus (DM), it is well established that physical exercise continues to be one of the most valuable forms of non-pharmacological therapy. The aim of the study was to investigate the effects of exercise training on excitation-contraction coupling and related gene expression in the Goto-Kakizaki (GK) type 2 diabetic rat heart and whether exercise is able to reverse diabetes-induced changes in excitation-contraction coupling and gene expression. Experiments were performed in GK and control rats aged 10-11 months following 2-3 months of treadmill exercise training. Shortening, [Ca2+]i and L-type Ca 2+ current were measured in ventricular myocytes with video edge detection, fluorescence photometry and whole cell patch clamp techniques, respectively. Expression of mRNA was assessed in ventricular muscle with real-time RT-PCR. Amplitude of shortening, Ca2+ transients and L-type Ca2+ current were not significantly altered in ventricular myocytes from GK sedentary compared to control sedentary rats or by exercise training. Expression of mRNA encoding Tpm2, Gja4, Atp1b1, Cacna1g, Cacnb2, Hcn2, Kcna3 and Kcne1 were up-regulated and Gja1, Kcnj2 and Kcnk3 were down-regulated in hearts of sedentary GK rats compared to sedentary controls. Gja1, Cav3 and Kcnk3 were up-regulated and Hcn2 was down-regulated in hearts of exercise trained GK compared to sedentary GK controls. Ventricular myocyte shortening and Ca 2+ transport were generally well preserved despite alterations in the profile of expression of mRNA encoding a variety of cardiac muscle proteins in the adult exercise trained GK diabetic rat heart.
KW - Calcium transport
KW - Cardiac muscle contraction
KW - Exercise training
KW - Gene expression
KW - Goto-Kakizaki rat
KW - Type 2 diabetes mellitus
KW - Ventricular myocytes
KW - mRNA
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U2 - 10.1007/s11010-013-1662-2
DO - 10.1007/s11010-013-1662-2
M3 - Article
C2 - 23620341
AN - SCOPUS:84879799028
SN - 0300-8177
VL - 380
SP - 83
EP - 96
JO - Molecular and cellular biochemistry
JF - Molecular and cellular biochemistry
IS - 1-2
ER -