Fig. 1

Preventive and curative orexin A treatments dramatically alleviate EAE symptoms. Chronic EAE was induced with 100 μg of MOG_35–55 to 9-week-old female C57BL/6 mice (n = 10/group). Panels show clinical signs of EAE scored daily for over 30 days on a scale of 0–5 as described in the “Methods” section. a Shows intraperitoneally (IP) administered PBS (PBS group), 100 μg/mouse of orexin A for 5 days starting on day 3 (= before the onset, BOxA₁₀₀ IP group) or starting when mice exhibit a moderate EAE score (= 1.5 for OxA₁₀₀ IP group). b Shows IP given PBS (PBS group), 100 μg/mouse of orexin A (OxA₁₀₀ IP group) or 300 μg/mouse of orexin A (OxA₃₀₀ IP group), as well as retro-orbital (RO) injection with 300 μg/mouse of orexin A (OxA₃₀₀ RO group) for a 5 day administration starting at moderate EAE (= 1.5). Clinical curves represent mean clinical scores ± SEM. *P < 0.05 (Two-way ANOVA compared to PBS group). For all clinical studies, maximal EAE score and mean EAE score were assessed. *P < 0.05 (Kruskal-Wallis test with Dunn’s post-hoc test for multiple comparisons with PBS group). c Shows the percentage of weight loss (in comparison with the initial weight before EAE induction) during the disease development. Shown results are representative of three independent experiments with n = 10 animals/group each