Open Access

ARTICLE

Effects of docosahexaenoic acid or arachidonic acid supplementation on gene expression and contractile force of rat cardiomyocytes in primary culture

by MIZUNA YANO¹, YUTA UMEHARA¹, TOMOKAZU KUDO¹, TAKAO NAKAMURA², TADASHI KOSAWADA¹, ATSUYOSHI NISHINA³, MASAKI SAZUKA⁴, DAISUKE SATO¹, ZHONGGANG FENG¹

1 Graduate School of Science and Engineering, Yamagata University, Yonezawa, 9928510, Japan
2 Graduate School of Medical Science, Yamagata University, Yamagata, 9909585, Japan
3 Department of Materials and Applied Chemistry, College of Science and Technology, Nihon University, Tokyo, 1018308, Japan
4 Department of Health and Nutrition, Yamagata Prefectural Yonezawa University of Nutrition Sciences, Yonezawa, 9920025, Japan

(This article belongs to the Special Issue: Cellular Biomechanics in Health and Diseases)

BIOCELL 2021, 45(5), 1213-1229. https://doi.org/10.32604/biocell.2021.016281

Received 23 February 2021; Accepted 26 April 2021; Issue published 12 July 2021

Abstract

While fatty acids play essential roles in the physiology of the myocardium, conventional culture media contain little lipid. We previously revealed that rat neonatal myocardium mainly contains docosahexaenoic (DHA), linoleic (LA), and arachidonic (AA) acids as polyunsaturated fatty acids (PUFAs), and these contents in cultured cardiomyocytes derived from fetal rats were markedly lower than those in the neonatal myocardium. In this study, we first assessed the effects of supplementation of DHA, LA, or AA on the fatty acid contents and the percentage change of contractile area in primarily cultured rat cardiomyocytes. Based on this assessment, we then evaluated the effects of DHA or AA supplementation on mRNA expression and further directly measured the contractile force of cardiomyocytes with the supplementations. This study revealed that percentage change of contractile area was maximized under 20 μM DHA or 50 μM AA supplementation while LA supplementation did not affect this contraction index, and that a widespread upregulation tendency of the mRNA expression related to differentiation, maturity, fatty acid metabolism, and cell adhesion was seen in the cultured cardiomyocytes with supplementation of DHA or AA. In particular, upregulation of the gene expression of cellular adhesion molecules connexin43 and N-cadherin were remarkable, whereas the effects on differentiation and maturation were less pronounced. Correspondingly, the increase of the percentage change of the contractile area of cardiomyocyte clusters in culture dishes with the supplementations was significant, whereas the enhancement of the contractile force was modest. These results suggest that supplementation of DHA or AA to the fetal cardiomyocyte culture may play effective roles in preventing the de-differentiation of the cardiomyocytes in culture and that the enhancement of the contractile performance may be mainly attributed to the improvement of intercellular connection.

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