posted on 2020-03-18, 18:42authored byYabei Li, Jinxin Lang, Zhaoyang Ye, Meng Wang, Yaowei Yang, Xiaojin Guo, Jian Zhuang, Junjie Zhang, Feng Xu, Fei Li
Mechanical microenvironment
plays a key role in the regulation
of the phenotype and function of cardiac cells, which are strongly
associated with the intracellular redox mechanism of cardiomyocytes.
However, the relationship between the redox state of cardiomyocytes
and their mechanical microenvironment remains elusive. In this work,
we used polyacrylamide (PA) gels with varying stiffness (6.5–92.5
kPa) as the substrate to construct a mechanical microenvironment for
cardiomyocytes. Then we employed scanning electrochemical microscopy
(SECM) to in situ characterize the redox state of a single cardiomyocyte
in terms of the apparent rate constant (kf) of the regeneration rate of ferrocenecarboxylic by glutathione
(GSH) released from cardiomyocyte, which is the most abundant reactant
of intracellular reductive-oxidative metabolic cycles in cells and
can represent the redox level of cardiomyocytes. The obtained SECM
results show that the cardiomyocytes cultured on the stiffer substrates
present lower kf values than those on
the softer ones, that is, the more oxidative state of cardiomyocytes
on the stiffer substrates compared to those on the softer ones. It
proves the relationship between mechanical factors and the redox state
of cardiomyocytes. This work can contribute to understanding the intracellular
chemical process of cardiomyocytes during physiopathologic conditions.
Besides, it also provides a new SECM method to in situ investigate
the redox mechanism of cardiomyocytes at a single-cell level.