An optimized whole-body cortisol quantification method for assessing stress levels in larval zebrafish

Area of Science:

• Endocrinology
• Neuroscience
• Zebrafish Model Organisms

Background:

• Glucocorticoids are vital for physiological regulation and mediating the stress response.
• While essential for survival, abnormal stress responses are linked to human diseases like depression and metabolic disorders.
• Zebrafish (Danio rerio) are valuable models for stress research due to genetic tractability and behavioral analysis capabilities.

Purpose of the Study:

• To develop an efficient, low-cost method for measuring stress hormone levels in larval zebrafish.
• To facilitate systematic and large-scale stress analyses in zebrafish larvae.
• To characterize the stress response of larval zebrafish to various stressors.

Main Methods:

• Optimized sample collection and cortisol extraction techniques for zebrafish larvae.
• Developed a custom, home-made Enzyme-Linked Immunosorbent Assay (ELISA) protocol.
• Quantified whole-body cortisol levels in larval zebrafish using the developed assay.

Main Results:

• Successfully established and optimized a novel ELISA protocol for cortisol measurement in larval zebrafish.
• Demonstrated the utility of the assay by characterizing larval zebrafish responses to diverse stressors.
• Validated the method for efficient and cost-effective cortisol quantification.

Conclusions:

• The developed home-made ELISA assay provides a crucial tool for measuring stress hormone levels in larval zebrafish.
• This assay will significantly advance systematic and large-scale stress response research in this model organism.
• Facilitates deeper understanding of the mechanisms underlying stress and its implications for health and disease.