Comparative Study in Zebrafish and Medaka Unravels the Mechanisms of Tissue Regeneration

Abstract

Tissue regeneration has been in the spotlight of research for its fascinating nature and potential applications in human diseases. The trait of regenerative capacity occurs diversely across species and tissue contexts, while it seems to decline over evolution. Organisms with variable regenerative capacity are usually distinct in phylogeny, anatomy, and physiology. This phenomenon hinders the feasibility of studying tissue regeneration by directly comparing regenerative with non-regenerative animals, such as zebrafish (Danio rerio) and mice (Mus musculus). Medaka (Oryzias latipes) is a fish model with a complete reference genome and shares a common ancestor with zebrafish approximately 110–200 million years ago (compared to 650 million years with mice). Medaka shares similar features with zebrafish, including size, diet, organ system, gross anatomy, and living environment. However, while zebrafish regenerate almost every organ upon experimental injury, medaka shows uneven regenerative capacity. Their common and distinct biological features make them a unique platform for reciprocal analyses to understand the mechanisms of tissue regeneration. Here we summarize current knowledge about tissue regeneration in these fish models in terms of injured tissues, repairing mechanisms, available materials, and established technologies. We further highlight the concept of inter-species and inter-organ comparisons, which may reveal mechanistic insights and hint at therapeutic strategies for human diseases.

Longitudinal in vivo imaging of adult Danionella cerebrum using standard confocal microscopy

“…It is interesting that not all model fish species possess similar competencies with respect to regeneration. For example, compared with zebrafish, another commonly used fish species, the medaka ( Oryzias latipes ), shows a very different capacity for regeneration ( Chowdhury et al, 2022 ; Lai et al, 2017 ). The regenerative capacity of D. cerebrum is currently unknown.…”

Two decades of heart regeneration research: Cardiomyocyte proliferation and beyond

“…Finally, it is likely that cardiomyocyte polyploidization is not the only barrier limiting cardiac regeneration. Though the hearts of medaka consist primarily of diploid cardiomyocytes (Chowdhury et al, 2022; Ito et al, 2014), heart regeneration still fails in these animals. This suggests that retaining high diploid cardiomyocyte frequency may not be sufficient to support a robust cardiac regenerative response.…”

“…This suggests that retaining high diploid cardiomyocyte frequency may not be sufficient to support a robust cardiac regenerative response. It is likely that extrinsic signals, possibly from recruited or resident macrophages, are additionally required to stimulate cardiomyocyte proliferation (Chowdhury et al, 2022; Ito et al, 2014; Lai et al, 2017).…”

Zebrafish and Medaka as model organisms for climate change research: Global literature scientometric analysis

“…Zebrafish and Medaka are species living in freshwater and marine water environments (Hsu et al, 2014), thus making them suitable organisms for understanding organism function changes within climate change-related studies in either environment. Zebrafish and Medaka's ecology and evaluation are well established as natural model organisms, and knowledge of how they should best be managed is vital for various research (Marx, 2021;Chowdhury et al, 2022). In addition, Zebrafish and Medaka also share the same anatomy, genetic, and physiological elements (Hsu et al, 2014;Chowdhury et al, 2022).…”

“…Zebrafish and Medaka's ecology and evaluation are well established as natural model organisms, and knowledge of how they should best be managed is vital for various research (Marx, 2021;Chowdhury et al, 2022). In addition, Zebrafish and Medaka also share the same anatomy, genetic, and physiological elements (Hsu et al, 2014;Chowdhury et al, 2022).…”