mTOR Modulation of IKr through hERG1b-Dependent Mechanisms in Lipotoxic Heart
Abstract
:1. Introduction
2. Results
2.1. mTOR Inhibition Prevented Increases in hERG1a/1b Currents in Lipotoxic HEK293 Cells
2.2. Lipotoxicity-Induced Increases in hERG1a/1b Involve PI3K/Akt and AMPK Pathways
2.3. Lipotoxicity Upregulates hERG1a/1b Current Density by Promoting Translation of hERG1b
2.4. mTOR Inhibition Slowed hERG Channel Inactivation in HEK293 Cells
2.5. mTOR Activation Increased IKr and Shortened APDs in Lipotoxic Atrial Myocytes
3. Discussion
Limitations of the Study
4. Materials and Methods
4.1. Cell Culture
4.2. Guinea Pig Atrial Myocyte Isolation
4.3. Preparation of Bovine Serum Albumin (BSA)-Conjugated FFA Solutions
4.4. Low-Fat-Diet and High-Fat-Diet (Palmitic-Acid Diet) Feeding in Guinea Pigs
4.5. Electrophysiology
4.6. Western Blot Analysis
4.7. Data Analyses
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Aromolaran, K.A.; Do, J.; Bernardi, J.; Aromolaran, A.S. mTOR Modulation of IKr through hERG1b-Dependent Mechanisms in Lipotoxic Heart. Int. J. Mol. Sci. 2022, 23, 8061. https://doi.org/10.3390/ijms23158061
Aromolaran KA, Do J, Bernardi J, Aromolaran AS. mTOR Modulation of IKr through hERG1b-Dependent Mechanisms in Lipotoxic Heart. International Journal of Molecular Sciences. 2022; 23(15):8061. https://doi.org/10.3390/ijms23158061
Chicago/Turabian StyleAromolaran, Kelly A., Jenny Do, Joyce Bernardi, and Ademuyiwa S. Aromolaran. 2022. "mTOR Modulation of IKr through hERG1b-Dependent Mechanisms in Lipotoxic Heart" International Journal of Molecular Sciences 23, no. 15: 8061. https://doi.org/10.3390/ijms23158061