Unbalance Between Sarcoplasmic Reticulum Ca2 + Uptake and Release: A First Step Toward Ca2 + Triggered Arrhythmias and Cardiac Damage

The present review focusses on the regulation and interplay of cardiac SR Ca2+ handling proteins involved in SR Ca2+ uptake and release, i.e., SERCa2/PLN and RyR2. Both RyR2 and SERCA2a/PLN are highly regulated by post-translational modifications and/or different partners’ proteins. These control mechanisms guarantee a precise equilibrium between SR Ca2+ reuptake and release. The review then discusses how disruption of this balance alters SR Ca2+ handling and may constitute a first step toward cardiac damage and malignant arrhythmias. In the last part of the review, this concept is exemplified in different cardiac diseases, like prediabetic and diabetic cardiomyopathy, digitalis intoxication and ischemia-reperfusion injury.
Source: Frontiers in Physiology - Category: Physiology Source Type: research

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Abstract Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice with implications on long-term outcomes. Metabolic disorders including diabetes mellitus and obesity are independent predictors of atrial fibrillation and present therapeutic targets to reduce both the incidence and duration burden of atrial fibrillation. The presence of pericardial fat in direct contact with cardiac structures, as well the subsequent release of proinflammatory cytokines, may play an important role in this connection. Atrial fibrillation is an independent predictor of cognitive impairment and dementia....
Source: Medicina (Kaunas) - Category: Universities & Medical Training Authors: Tags: Medicina (Kaunas) Source Type: research
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Source: Acta Cardiologica - Category: Cardiology Tags: Acta Cardiol Source Type: research
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Source: Medicina (Kaunas) - Category: Universities & Medical Training Authors: Tags: Medicina (Kaunas) Source Type: research
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Source: Circulation Journal - Category: Cardiology Authors: Tags: Circ J Source Type: research
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Source: Pacing and Clinical Electrophysiology : PACE - Category: Cardiology Authors: Tags: ELECTROPHYSIOLOGY Source Type: research
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Source: Journal of Nuclear Medicine - Category: Nuclear Medicine Authors: Tags: Cardiovascular Clinical Science Posters Source Type: research
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Source: Frontiers in Physiology - Category: Physiology Source Type: research
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Source: Frontiers in Physiology - Category: Physiology Source Type: research
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Source: Current Vascular Pharmacology - Category: Drugs & Pharmacology Authors: Tags: Curr Vasc Pharmacol Source Type: research
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Source: Clinical Research in Cardiology - Category: Cardiology Source Type: research
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