A mouse model for chronic pain-induced increase in ethanol consumption

Area of Science:

• Neuroscience
• Pain Research
• Addiction Studies

Background:

• Chronic pain conditions frequently co-occur with alcohol abuse.
• Self-medication with alcohol can worsen pain and lead to abuse-related problems.
• Existing rodent models for comorbid chronic pain and alcohol abuse are limited.

Purpose of the Study:

• To develop and validate a preclinical rodent model for comorbid osteoarthritis (OA) and alcohol abuse.
• To investigate the relationship between OA severity and ethanol intake in mice.

Main Methods:

• Osteoarthritis was surgically induced in C57BL/6J mice via destabilization of the medial meniscus (DMM).
• Sham-operated mice served as controls.
• Mice were exposed to a two-bottle ethanol choice paradigm, with ethanol concentration gradually increasing.
• Hind limb incapacitance, OA-related joint damage, and ethanol consumption were assessed.

Main Results:

• DMM mice exhibited significant hind limb incapacitance compared to sham controls.
• Histological analysis confirmed OA-related cartilage damage and osteophyte formation in DMM mice.
• DMM mice consumed significantly more ethanol and preferred it over water at higher concentrations.
• The severity of OA correlated with increased ethanol intake.

Conclusions:

• The DMM-induced OA model combined with the two-bottle ethanol choice provides a viable preclinical approach.
• This model can be used to explore the underlying mechanisms of the comorbidity between chronic pain and alcohol abuse.