In Vitro Studies of Enteric Glia Facing Inflammatory Stimuli

Background: Under normal physiological conditions, the enteric glial cells (EGC) are crucial to numerous functions, such as the regulation of intestinal epithelial barrier (IEB). However, in a pathological condition, it becomes reactive, having a proinflammatory role, expressing NFKB and increasing S100β release. Our exploratory studies aim to understand how EGC becomes reactive when facing inflammatory and tumoral situations, and how this reactive state affects IEB and colorectal cancer.

Methods: MTT assay with EGC (CRL2690 lineage) exposed to different concentrations of LPS in 24h and 48h. EGC immunocytochemistry after 24h and 48h with LPS treatment. ELISA assay for S100β. Nitrate oxide (NO) assay of LPS-treated EGC conditioned medium.

Results and Conclusions: Our preliminary results show that, in the MTT assays, treatment with LPS 10 or 20 μg/ml resulted in a viability less than 50% in 24h, so the following experiments were made with reduced concentrations. In immunocytochemistry, EGC treated with 5 μg/ml LPS provoked an increase in S100β expression after 24h and 48h. GFAP levels increased after 48h to LPS 10 μg/ml despite the noticed cell death. Cx43 levels after 24h exposition to LPS in all conditions. NO assay early results point an upward trend by increasing concentration and exposure time to LPS. On the other hand, HCT116 treated with conditioned mediums of EGC treated with different concentrations of LPS did not change its cell viability. This work will allow us to comprehend how EGC reacts under inflammatory and tumoral stimuli.