We evaluated the elasticity of live tissues of zebrafish embryos using label‐free optical elastography. We employed a pair of custom‐built elastic microcantilevers to gently compress a zebrafish embryo and used optical‐tracking analysis to obtain the induced internal strain. We then built a finite element method (FEM) model and matched the strain with the optical analysis. The elastic moduli were found by minimizing the root‐mean‐square errors between the optical and FEM analyses. We evaluated the average elastic moduli of a developing somite, the overlying ectoderm, and the underlying yolk of seven zebrafish embryos during the early somitogenesis stages. The estimation results showed that the average elastic modulus of the somite increased from 150 to 700 Pa between 4‐ and 8‐somite stages, while those of the ectoderm and the yolk stayed between 100 and 200 Pa, and they did not show significant changes. The result matches well with the developmental process of somitogenesis reported in the literature. This is among the first attempts to quantify spatially‐resolved elasticity of embryonic tissues from optical elastography.
Glutathione (GSH) plays fundamental roles in cellular redox buffering and is a common detoxification pathway for excretion of xenobiotics. This is especially crucial during vertebrate embryogenesis, when an organism is at one of its most vulnerable life stages. Importantly, GSH content and redox potential can dictate cell fate decisions, which can have profound consequences if altered by early life xenobiotic exposures. Owing to technical limitations, the best available method to detect and quantify changes in GSH has been high‐pressure liquid chromatography, a terminal method that prevents suborganism‐level resolution of these changes in developing embryos. Here, we describe a protocol that leverages the transparent nature of zebrafish embryos and the compatibility of monochlorobimane with the zebrafish GSH‐S‐transferase enzymes, to allow for the visualization of changes in GSH via S‐glutathionylation in a live, developing embryo. This method can find broad application in developmental biology and toxicology. © 2021 Wiley Periodicals LLC.
This article was corrected on 19 July 2022. See the end of the full text for details.
more » « less- NSF-PAR ID:
- 10228113
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Current Protocols
- Volume:
- 1
- Issue:
- 2
- ISSN:
- 2691-1299
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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