Modeling disease in rodents is essential for preclinical research, particularly in the development of drugs and therapies. Traditional disease modeling approaches often rely on invasive and stressful procedures such as repeated injections and/or surgical approaches. These methods raise welfare concerns and can introduce stress-related variables that compromise model reliability. Cuprizone (CPZ) is a copper-chelating compound widely used to induce CNS demyelination in mice over a 6-week period via incorporation into ground rodent chow. However, the presumed adverse taste of CPZ reduces food intake, resulting in weight loss, inconsistent consumption, and variable levels of demyelination, complicating disease comparison. To address this, we proposed that mixing CPZ into peanut butter (CPZ-PB) would promote voluntary intake, standardize daily dosing, and minimize weight loss, while maintaining effective demyelination. Thirty mice were divided into control, CPZ-PB, or CPZ-chow groups and received treatment daily for 6 weeks. Body weight and CPZ intake were recorded daily. The effect of demyelination through mechanical allodynia was assessed via the dynamic plantar aesthesiometer. Immunohistochemical analysis of myelin proteins and astrocyte activation was conducted on the brain and spinal cord after 6 weeks of treatment. Voluntary consumption of CPZ-PB successfully ameliorated weight loss concerns and achieved consistent daily CPZ dosing. Behavioral and immunohistochemical analyses confirmed effective demyelination comparable to traditional CPZ-chow methods. This study introduces an improved CPZ administration strategy that enhances animal welfare and provides a more reliable model for demyelination research.
Hawker et al. (Sun,) studied this question.