Seyedeh Nikan Nejat - Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Javad Arasteh - Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran
Maryam Tajabadi Ebrahimi - Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran

Multiple sclerosis is a chronic disease and neurodegenerative disorder that affects the central nervous system and the nerves, leading to the destruction of myelin, which protects the fibers of the neural cells in the brain and spinal cord. One of the important cytosolic DNA sensors is AIM2, which in fact AIM2 is a protein encoded in humans by the AIM2 gene. AIM2 is a member of the Ifi202/IFI16 family. It plays a putative role in tumorigenic reversion and may control cell proliferation. IFN-γ induces expression of AIM2. The C-terminal HIN domain binds double-stranded DNA (viral, bacterial, or even host) and acts as a cytosolic dsDNA sensor. This leads to the oligomerization of the inflammasomecomplex. AIM2 plays an important role in MS by the Th1, Th17 response. The aim of this study was to investigate the effect of Pediococcus acidilactici on the expression of AIM2 gene in demyelinated C57BL/6 mouse model. Materials and Methods: 30 adult female C57BL/6were divided in to 5 separate groups. First control was Healthy mice group that only they received sterile water by oral gavage to induce stress, second control received 0.2% cuprizone by oral gavage for 4 weeks, third control group received probiotic with 109 cfu concentration for 8 weeks. Mice in treatment groups were divided in to two groups to survey the prevention and betterment effects of Pediococcus acidilactici. The Prevention group received probiotic with 109 cfu concentration for 2 weeks then cuprizone for 4 weeks. The bettermentgroup received cuprizone for 4 weeks, then probiotic with 109 cfu concentration for 4 weeks. The Luxol Fast Blue staining was used to affirm the existence of demyelination. The quantity of AIM2expression was measured by Real-Time PCR. Results: The results indicate that Pediococcus acidilactici, makes significant difference between the cuprizone control group and treatment groups (p = 0.000 <0.05). Conclusion: We verify that Pediococcus acidilactici has potential effects as a novel probiotic on betterment of MS.