HCN4-Overexpressing Mouse Embryonic Stem Cell-Derived Cardiomyocytes Generate a New Rapid Rhythm in Rats with Bradycardia
-
- Saito Yukihiro
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
-
- Nakamura Kazufumi
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
-
- Yoshida Masashi
- Department of Chronic Kidney Disease and Cardiovascular Disease, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
-
- Sugiyama Hiroki
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
-
- Takano Makoto
- Department of Physiology, Kurume University School of Medicine
-
- Nagase Satoshi
- Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
-
- Morita Hiroshi
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
-
- Kusano Kengo F.
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences Department of Cardiovascular Medicine, National Cerebral and Cardiovascular Center
-
- Ito Hiroshi
- Department of Cardiovascular Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences
Search this article
Abstract
<p>A biological pacemaker is expected to solve the persisting problems of an artificial cardiac pacemaker including short battery life, lead breaks, infection, and electromagnetic interference. We previously reported HCN4 overexpression enhances pacemaking ability of mouse embryonic stem cell-derived cardiomyocytes (mESC-CMs) in vitro. However, the effect of these cells on bradycardia in vivo has remained unclear. Therefore, we transplanted HCN4-overexpressing mESC-CMs into bradycardia model animals and investigated whether they could function as a biological pacemaker. The rabbit Hcn4 gene was transfected into mouse embryonic stem cells and induced HCN4-overexpressing mESC-CMs. Non-cardiomyocytes were removed under serum/glucose-free and lactate-supplemented conditions. Cardiac balls containing 5 × 103 mESC-CMs were made by using the hanging drop method. One hundred cardiac balls were injected into the left ventricular free wall of complete atrioventricular block (CAVB) model rats. Heart beats were evaluated using an implantable telemetry system 7 to 30 days after cell transplantation. The result showed that ectopic ventricular beats that were faster than the intrinsic escape rhythm were often observed in CAVB model rats transplanted with HCN4-overexpressing mESC-CMs. On the other hand, the rats transplanted with non-overexpressing mESC-CMs showed sporadic single premature ventricular contraction but not sustained ectopic ventricular rhythms. These results indicated that HCN4-overexpressing mESC-CMs produce rapid ectopic ventricular rhythms as a biological pacemaker.</p>
Journal
-
- International Heart Journal
-
International Heart Journal 59 (3), 601-606, 2018-05-31
International Heart Journal Association