26:T49b,

The study investigates the role of cobalt chloride (CoCl₂), a hypoxia-inducing agent, in promoting tissue regeneration using zebrafish as a model system. Caudal fins of adult zebrafish were amputated and transdermally exposed to 1% CoCl₂. The extent of fin regeneration and the neovascularization process at the growth front were analyzed. CoCl₂ exposure significantly enhanced regeneration compared with controls, with increased fin length and more prominent blood vessel sprouting and anastomosis. Molecular and proteomics analyses revealed an upregulation of angiogenic and pro-angiogenic factors, particularly Vascular Endothelial Growth Factor (VEGF). To verify the role of VEGF in CoCl₂-mediated tissue regeneration, the amputated fins were exposed to inhibitors such as genistein and SU5416. These results suggest that CoCl₂ promotes tissue regrowth and wound healing by stimulating angiogenesis. The findings highlight the therapeutic potential of CoCl₂ in enhancing regeneration and wound repair through the HIF-1α/VEGF signaling pathway, with potential implications for treating ischemic wounds.

27:T4b8,

Chorions, also known as egg membranes, form quickly after fertilization and play a role in subsequent embryonic development in fish. While the enzymatic hardening of the chorion due to the release of cortical alveoli (CA) components by the exocytosis of CA has been well-demonstrated, the initiation mechanism of this process has remained unresolved. Knockout lines with the prss59.1 trypsin paralog gene exhibited abnormalities in chorion elevation. Prss59.1 has been shown to be expressed on the chorion’s surface. Therefore, we hypothesized that a trypsin-like enzyme expressed on the chorion could trigger chorion elevation.

In this study, we attempted to improve the effectiveness of Hank’s solution at preventing chorion elevation. By adjusting the concentration of the solution’s contents, we developed a modified Hank’s solution that can stop chorion elevation almost completely. Using this solution, we demonstrated that trypsin can induce chorion elevation. These results support our hypothesis that a trypsin-like enzyme initiates chorion elevation. This assay method can be used for the further analysis of the chorion elevation mechanism.

28:T5ae,