We aimed to explore whether specific high-sucrose intake in older female rats affects myocardial electrical coupling protein, connexin-43 (Cx43), protein kinase C (PKC) signaling, miR-1 and miR-30a expression, and susceptibility of the heart to malignant arrhythmias. Possible benefit of the supplementation with melatonin (40 μg/ml/day) and omega-3 polyunsaturated fatty acids (Omacor, 25 g/kg of rat chow) was examined as well. Results have shown that 8 weeks lasting intake of 30% sucrose solution increased serum cholesterol, triglycerides, body weight, heart weight, and retroperitoneal adipose tissues. It was accompanied by downregulation of cardiac Cx43 and PKCε signaling along with an upregulation of myocardial PKCδ and miR-30a rendering the heart prone to ventricular arrhythmias. There was a clear benefit of melatonin or omega-3 PUFA supplementation due to their antiarrhythmic effects associated with the attenuation of myocardial Cx43, PKC, and miR-30a abnormalities as well as adiposity. The potential impact of these findings may be considerable, and suggests that high-sucrose intake impairs myocardial signaling mediated by Cx43 and PKC contributing to increased susceptibility of the older obese female rat hearts to malignant arrhythmias.
- MeSH
- Anti-Arrhythmia Agents metabolism pharmacology MeSH
- Connexin 43 metabolism MeSH
- Dietary Sucrose adverse effects MeSH
- Rats MeSH
- Melatonin metabolism pharmacology MeSH
- MicroRNAs metabolism MeSH
- Myocardium metabolism MeSH
- Obesity chemically induced complications drug therapy metabolism MeSH
- Fatty Acids, Omega-3 metabolism pharmacology MeSH
- Rats, Wistar MeSH
- Protein Kinase C-delta metabolism MeSH
- Protein Kinase C-epsilon metabolism MeSH
- Signal Transduction drug effects MeSH
- Heart drug effects MeSH
- Arrhythmias, Cardiac etiology MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
