Conjugated linoleic acid prevents age-dependent neurodegeneration in a mouse model of neuropsychiatric lupus via the activation of an adaptive response.

Oxidative stress is a key mediator of autoimmune/neurodegenerative disorders. The antioxidant/anti-inflammatory effect of a synthetic conjugated linoleic acid (CLA) mixture in MRL/MpJ-Faslpr mice (MRL/lpr), an animal model of neuropsychiatric lupus, was previously associated with the improvement of Nuclear factor-E2-related factor 2 (Nrf2) defences in the spleen and liver. However, little is known about the neuroprotective ability of CLA mixture. This study investigates the age-dependent progression of oxidative stress and the hyperactivation of redox-sensitive compensatory pathways (macroautophagy, Nrf2) in old/diseased MRL/lpr mice brains, and examines the effect produced by dietary CLA supplementation. Disrupted redox homeostasis was evidenced in the blood, liver and brain of 21- to 22-week old MRL/lpr mice (Old) compared to young animals (Y; 8- to 10-week old). This alteration was associated with significant hyperactivation of compensatory mechanisms (macroautophagy, Nrf2 and astrocyte activation) in the brains of Old mice. Five-week daily supplementation with CLA (650 mg/kg-1 body weight) of 16-week old mice (CLA+Old) diminished all the pathological hallmarks at a level comparable to Y mice or healthy controls (BALB/c). Such data demonstrated that MRL/lpr mice can serve as a valuable model for the evaluation of the effectiveness of neuroprotective drugs. Notably, the preventive effect provided by CLA supplementation against age-associated neuronal damage and hyperactivation of compensatory mechanisms suggests that the activation of an adaptive response is, at least in part, accountable for its neuroprotective ability.