Prepared by: Assoc. Prof. Dr. Siti Munirah Mohd Faudzi

Mice and rats are commonly used as animal models in clinical research studies. However, experiments involving these complex mammalian models are often expensive, time-consuming, and raise ethical concerns regarding animal welfare. Consequently, all research utilizing in vivo models must adhere to the ethical guidelines set by standard committees, where the "3R" principles (Replacement, Refinement, and Reduction) are fully implemented. Moreover, the U.S. Environmental Protection Agency (EPA) has announced plans to eliminate the use of mammalian animals in toxicological and clinical testing by 2035. In line with these principles and mandates, zebrafish, scientifically known as Danio rerio, has emerged as a potential alternative in vivo model in toxicology studies.

Zebrafish are genetically similar to humans by 70%, with 84% of their genes corresponding to human diseases. Additionally, zebrafish exhibit rapid external development and reproduction rates, are easy to handle, and can be genetically modified with ease, allowing for swift and effective research. The transparency of zebrafish embryos facilitates direct observation of the toxic effects of chemicals on the development of living organisms, including parameters such as neurotoxicity, cardiotoxicity, and mortality. This enables chemists to detect and analyze molecular and cellular changes resulting from acute (short-term) or chronic (long-term) exposure to specific chemical compounds.

According to the EU Directive 2010/63/EU on the protection of animals used for scientific purposes, zebrafish up to 5 days post-fertilization (dpf) are not classified as animals, making them an important in vivo model specifically in the field of drug discovery. Therefore, zebrafish serve as a valuable preclinical model in drug discovery, neuroscience, and ecotoxicology, helping to ensure the safety and efficacy of drug candidates before they are tested in humans.

Date of Input: 04/06/2024 | Updated: 04/06/2024 | hidayahsaleh