Molecular and behavioural abnormalities in the FUS‐tg mice mimic frontotemporal lobar degeneration: Effects of old and new anti‐inflammatory therapies

Genetic mutations in FUS, a DNA/RNA‐binding protein, are associated with inherited forms of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). A novel transgenic FUS[1‐359]‐tg mouse line recapitulates core hallmarks of human ALS in the spinal cord, including neuroinflammation and neurodegeneration, ensuing muscle atrophy and paralysis, as well as brain pathomorphological signs of FTLD. However, a question whether FUS[1‐359]‐tg mouse displays behavioural and brain pro‐inflammatory changes characteristic for the FTLD syndrome was not addressed. Here, we studied emotional, social and cognitive behaviours, brain markers of inflammation and plasticity of pre‐symptomatic FUS[1‐359]‐tg male mice, a potential FTLD model. These animals displayed aberrant behaviours and altered brain expression of inflammatory markers and related pathways that are reminiscent to the FTLD‐like syndrome. FTLD‐related behavioural and molecular Journal of Cellular and Molecular Medicine features were studied in the pre‐symptomatic FUS[1‐359]‐tg mice that received standard or new ALS treatments, which have been reported to counteract the ALS‐like syndrome in the mutants. We used anti‐ALS drug riluzole (8 mg/kg/d), or anti‐inflammatory drug, a selective blocker of cyclooxygenase‐2 (celecoxib, 30 mg/kg/d) for 3 weeks, or a single intracerebroventricular (i.c.v.) infusion of human stem cells (Neuro‐Cells, 500 000‐CD34(+)), which showed anti‐inflammatory properties. Signs of elevated anxiety, depressive‐like behaviour, cognitive deficits and abnormal social behaviour were less marked in FUS‐tg–treated animals. Applied treatments have normalized protein expression of interleukin‐1β (IL‐1β) in the prefrontal cortex and the hippocampus, and of Iba‐1 and GSK‐3β in the hippocampus. Thus, the pre‐symptomatic FUS[1‐359]‐tg mice demonstrate FTLD‐like abnormalities that are attenuated by standard and new ALS treatments, including Neuro‐Cell preparation.