Dataset Information

Sustained Toll-Like Receptor 9 Activation Promotes Systemic and Cardiac Inflammation, and Aggravates Diastolic Heart Failure in SERCA2a KO Mice.

ABSTRACT:

Aim

Cardiac inflammation is important in the pathogenesis of heart failure. However, the consequence of systemic inflammation on concomitant established heart failure, and in particular diastolic heart failure, is less explored. Here we investigated the impact of systemic inflammation, caused by sustained Toll-like receptor 9 activation, on established diastolic heart failure.

Methods and results

Diastolic heart failure was established in 8-10 week old cardiomyocyte specific, inducible SERCA2a knock out (i.e., SERCA2a KO) C57Bl/6J mice. Four weeks after conditional KO, mice were randomized to receive Toll-like receptor 9 agonist (CpG B; 2?g/g body weight) or PBS every third day. After additional four weeks, echocardiography, phase contrast magnetic resonance imaging, histology, flow cytometry, and cardiac RNA analyses were performed. A subgroup was followed, registering morbidity and death. Non-heart failure control groups treated with CpG B or PBS served as controls. Our main findings were: (i) Toll-like receptor 9 activation (CpG B) reduced life expectancy in SERCA2a KO mice compared to PBS treated SERCA2a KO mice. (ii) Diastolic function was lower in SERCA2a KO mice with Toll-like receptor 9 activation. (iii) Toll-like receptor 9 stimulated SERCA2a KO mice also had increased cardiac and systemic inflammation.

Conclusion

Sustained activation of Toll-like receptor 9 causes cardiac and systemic inflammation, and deterioration of SERCA2a depletion-mediated diastolic heart failure.

SUBMITTER: Dhondup Y

PROVIDER: S-EPMC4604200 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Sustained Toll-Like Receptor 9 Activation Promotes Systemic and Cardiac Inflammation, and Aggravates Diastolic Heart Failure in SERCA2a KO Mice.

Dhondup Yangchen Y Sjaastad Ivar I Scott Helge H Sandanger Øystein Ø Zhang Lili L Haugstad Solveig Bjærum SB Aronsen Jan Magnus JM Ranheim Trine T Holmen Sigve Dhondup SD Alfsnes Katrine K Ahmed Muhammad Shakil MS Attramadal Håvard H Gullestad Lars L Aukrust Pål P Christensen Geir G Yndestad Arne A Vinge Leif Erik LE

PloS one 20151013 10

<h4>Aim</h4>Cardiac inflammation is important in the pathogenesis of heart failure. However, the consequence of systemic inflammation on concomitant established heart failure, and in particular diastolic heart failure, is less explored. Here we investigated the impact of systemic inflammation, caused by sustained Toll-like receptor 9 activation, on established diastolic heart failure.<h4>Methods and results</h4>Diastolic heart failure was established in 8-10 week old cardiomyocyte specific, indu ...[more]

PMID: 26461521

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Dataset Information

Sustained Toll-Like Receptor 9 Activation Promotes Systemic and Cardiac Inflammation, and Aggravates Diastolic Heart Failure in SERCA2a KO Mice.

Aim

Methods and results

Conclusion

Publications

Sustained Toll-Like Receptor 9 Activation Promotes Systemic and Cardiac Inflammation, and Aggravates Diastolic Heart Failure in SERCA2a KO Mice.

Similar Datasets

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