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Title: Microscopic heat pulses induce contraction of cardiomyocytes without calcium transients

Abstract

Highlights: Black-Right-Pointing-Pointer Infra-red laser beam generates microscopic heat pulses. Black-Right-Pointing-Pointer Heat pulses induce contraction of cardiomyocytes. Black-Right-Pointing-Pointer Ca{sup 2+} transients during the contraction were not detected. Black-Right-Pointing-Pointer Skinned cardiomyocytes in free Ca{sup 2+} solution also contracted. Black-Right-Pointing-Pointer Heat pulses regulated the contractions without Ca{sup 2+} dynamics. -- Abstract: It was recently demonstrated that laser irradiation can control the beating of cardiomyocytes and hearts, however, the precise mechanism remains to be clarified. Among the effects induced by laser irradiation on biological tissues, temperature change is one possible effect which can alter physiological functions. Therefore, we investigated the mechanism by which heat pulses, produced by infra-red laser light under an optical microscope, induce contractions of cardiomyocytes. Here we show that microscopic heat pulses induce contraction of rat adult cardiomyocytes. The temperature increase, {Delta}T, required for inducing contraction of cardiomyocytes was dependent upon the ambient temperature; that is, {Delta}T at physiological temperature was lower than that at room temperature. Ca{sup 2+} transients, which are usually coupled to contraction, were not detected. We confirmed that the contractions of skinned cardiomyocytes were induced by the heat pulses even in free Ca{sup 2+} solution. This heat pulse-induced Ca{sup 2+}-decoupled contraction technique has the potential to stimulatemore » heart and skeletal muscles in a manner different from the conventional electrical stimulations.« less

Authors:
; ; ; ;  [1];  [2];  [3];  [1];  [4]
  1. Department of Physics, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555 (Japan)
  2. Department of Cell Physiology, The Jikei University School of Medicine, 3-25-8 Nishi-shinbashi, Minato-ku, Tokyo 105-8461 (Japan)
  3. Waseda Bioscience Research Institute in Singapore, Waseda University, 11 Biopolis Way, 05-01/02 Helios, Singapore 138667 (Singapore)
  4. (Singapore)
Publication Date:
OSTI Identifier:
22207645
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 417; Journal Issue: 1; Other Information: Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 60 APPLIED LIFE SCIENCES; AMBIENT TEMPERATURE; ANIMAL TISSUES; CALCIUM; CALCIUM IONS; CONTRACTION; HEART; HEAT; LASER RADIATION; LASERS; OPTICAL MICROSCOPES; RATS; TRANSIENTS; VISIBLE RADIATION

Citation Formats

Oyama, Kotaro, Mizuno, Akari, Shintani, Seine A., Itoh, Hideki, Serizawa, Takahiro, Fukuda, Norio, Suzuki, Madoka, E-mail: suzu_mado@aoni.waseda.jp, Ishiwata, Shin'ichi, E-mail: ishiwata@waseda.jp, and Waseda Bioscience Research Institute in Singapore, Waseda University, 11 Biopolis Way, 05-01/02 Helios, Singapore 138667. Microscopic heat pulses induce contraction of cardiomyocytes without calcium transients. United States: N. p., 2012. Web. doi:10.1016/J.BBRC.2011.12.015.
Oyama, Kotaro, Mizuno, Akari, Shintani, Seine A., Itoh, Hideki, Serizawa, Takahiro, Fukuda, Norio, Suzuki, Madoka, E-mail: suzu_mado@aoni.waseda.jp, Ishiwata, Shin'ichi, E-mail: ishiwata@waseda.jp, & Waseda Bioscience Research Institute in Singapore, Waseda University, 11 Biopolis Way, 05-01/02 Helios, Singapore 138667. Microscopic heat pulses induce contraction of cardiomyocytes without calcium transients. United States. doi:10.1016/J.BBRC.2011.12.015.
Oyama, Kotaro, Mizuno, Akari, Shintani, Seine A., Itoh, Hideki, Serizawa, Takahiro, Fukuda, Norio, Suzuki, Madoka, E-mail: suzu_mado@aoni.waseda.jp, Ishiwata, Shin'ichi, E-mail: ishiwata@waseda.jp, and Waseda Bioscience Research Institute in Singapore, Waseda University, 11 Biopolis Way, 05-01/02 Helios, Singapore 138667. 2012. "Microscopic heat pulses induce contraction of cardiomyocytes without calcium transients". United States. doi:10.1016/J.BBRC.2011.12.015.
@article{osti_22207645,
title = {Microscopic heat pulses induce contraction of cardiomyocytes without calcium transients},
author = {Oyama, Kotaro and Mizuno, Akari and Shintani, Seine A. and Itoh, Hideki and Serizawa, Takahiro and Fukuda, Norio and Suzuki, Madoka, E-mail: suzu_mado@aoni.waseda.jp and Ishiwata, Shin'ichi, E-mail: ishiwata@waseda.jp and Waseda Bioscience Research Institute in Singapore, Waseda University, 11 Biopolis Way, 05-01/02 Helios, Singapore 138667},
abstractNote = {Highlights: Black-Right-Pointing-Pointer Infra-red laser beam generates microscopic heat pulses. Black-Right-Pointing-Pointer Heat pulses induce contraction of cardiomyocytes. Black-Right-Pointing-Pointer Ca{sup 2+} transients during the contraction were not detected. Black-Right-Pointing-Pointer Skinned cardiomyocytes in free Ca{sup 2+} solution also contracted. Black-Right-Pointing-Pointer Heat pulses regulated the contractions without Ca{sup 2+} dynamics. -- Abstract: It was recently demonstrated that laser irradiation can control the beating of cardiomyocytes and hearts, however, the precise mechanism remains to be clarified. Among the effects induced by laser irradiation on biological tissues, temperature change is one possible effect which can alter physiological functions. Therefore, we investigated the mechanism by which heat pulses, produced by infra-red laser light under an optical microscope, induce contractions of cardiomyocytes. Here we show that microscopic heat pulses induce contraction of rat adult cardiomyocytes. The temperature increase, {Delta}T, required for inducing contraction of cardiomyocytes was dependent upon the ambient temperature; that is, {Delta}T at physiological temperature was lower than that at room temperature. Ca{sup 2+} transients, which are usually coupled to contraction, were not detected. We confirmed that the contractions of skinned cardiomyocytes were induced by the heat pulses even in free Ca{sup 2+} solution. This heat pulse-induced Ca{sup 2+}-decoupled contraction technique has the potential to stimulate heart and skeletal muscles in a manner different from the conventional electrical stimulations.},
doi = {10.1016/J.BBRC.2011.12.015},
journal = {Biochemical and Biophysical Research Communications},
number = 1,
volume = 417,
place = {United States},
year = 2012,
month = 1
}
  • One limitation in using human pluripotent stem cell derived cardiomyocytes (hPSC-CMs) for disease modeling and cardiac safety pharmacology is their immature functional phenotype compared with adult cardiomyocytes. Here, we report that treatment of human embryonic stem cell derived cardiomyocytes (hESC-CMs) with dexamethasone, a synthetic glucocorticoid, activated glucocorticoid signaling which in turn improved their calcium handling properties and contractility. L-type calcium current and action potential properties were not affected by dexamethasone but significantly faster calcium decay, increased forces of contraction and sarcomeric lengths, were observed in hESC-CMs after dexamethasone exposure. Activating the glucocorticoid pathway can thus contribute to mediating hPSC-CMs maturation.more » - Highlights: • Dexamethasone accelerates Ca{sup 2+} transient decay in hESC-CMs. • Dexamethasone enhances SERCA and NCX function in hESC-CMs. • Dexamethasone increases force of contraction and sarcomere length in hESC-CMs. • Dexamethasone does not alter I{sub Ca,L} and action potential characteristics in hESC-CMs.« less
  • Background: Autoantibodies have been identified as major predisposing factors for dilated cardiomyopathy (DCM). Patients with DCM show elevated serum levels of vascular endothelial growth factor (VEGF) whose source is unknown. Besides its well-investigated effects on angiogenesis, evidence is present that VEGF signaling is additionally involved in fibroblast proliferation and cardiomyocyte hypertrophy, hence in cardiac remodeling. Whether autoimmune effects in DCM impact cardiac VEGF signaling needs to be elucidated. Methods: Five DCM patients were treated by the immunoadsorption (IA) therapy on five consecutive days. The eluents from the IA columns were collected and prepared for cell culture. Cardiomyocytes from neonatal ratsmore » (NRCM) were incubated with increasing DCM-immunoglobulin-G (IgG) concentrations for 48 h. Polyclonal IgG (Venimmun N), which was used to restore IgG plasma levels in DCM patients after the IA therapy was additionally used for control cell culture purposes. Results: Elevated serum levels of VEGF decreased significantly after IA (Serum VEGF (ng/ml); DCM pre-IA: 45 ± 9.1 vs. DCM post–IA: 29 ± 6.7; P < 0.05). In cell culture, pretreatment of NRCM by DCM-IgG induced VEGF expression in a time and dose dependent manner. Biologically active VEGF that was secreted by NRCM significantly increased BNP mRNA levels in control cardiomyocytes and induced cell-proliferation of cultured cardiac fibroblast (Fibroblast proliferation; NRCM medium/HC-IgG: 1 ± 0.0 vs. NRCM medium/DCM-IgG 100 ng/ml: 5.6 ± 0.9; P < 0.05). Conclusion: The present study extends the knowledge about the possible link between autoimmune signaling in DCM and VEGF induction. Whether this observation plays a considerable role in cardiac remodeling during DCM development needs to be further elucidated. - Highlights: • Mechanisms of remodeling in dilated cardiomyopathy (DCM) are not fully understood. • Autoantibodies have been identified as major predisposing factors for DCM. • DCM patients show high serum levels of VEGF. • Recent data indicate that VEGF is involved in cardiac remodeling processes. • Whether autoimmune processes in DCM are involved in VEGF signaling are unclear.« less
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