Modulation of proinflammatory molecules production by autophagy pharmacological inhibitors in LPS-activated microglial cells.

MANZONE-RODRÍGUEZ, C; RODRIGUEZ, CM; IRIBARREN, P

Congreso; Reunión de Sociedades de Biociencias (SAIC SAI&FAIC SAFIS 2022); 2022

Objective: Microglial cells are phagocytes in the central nervous system (CNS) and become activated in pathological conditions, resulting in microgliosis, manifested by increased cell numbers and inflammation in the affected regions. Lipopolysaccharide (LPS) is able to activate and promote pro-inflammatory responses in microglial cells. For instance, stimulation of Toll-like receptor 4 (TLR4) induces the production of nitric oxide by these cells, which could be neurotoxic. We previously reported that TLR2 stimulation by peptidoglycan (PGN) from Staphylococcus aureus, induced microglial cell activation followed by autophagy induction. In addition, our findings suggest that activation of autophagy in microglial cells might modulate inflammatory responses in these cells. Therefore, our aim is to evaluate the modulatory effect of autophagy inhibitors in LPS-activated microglial cells.Methods: The murine microglial cell line BV2 was stimulated with LPS at different time points after pre-incubation in the presence or the absence of autophagy inhibitors (3-MA and spautin-1) or a general phosphatidyl-inositol-3 kinase (PI3K) inhibitor (LY294002). After treatment, microglial cells were processed to evaluate: 1) cytokine production by ELISA; 2) nitric oxide (NO) production by Griess reaction. All experiments were performed 3 times and p < 0.05 was considered to be statistically significant.Results: We observed that activation of microglial cells with LPS induced increase production of TNFalpha and NO (p < 0.001).Interestingly, treatment with autophagy inhibitors or a general PI3K inhibitor prevented the increased production of NO (p < 0.001). Additional experiments are currently performed to evaluate the effects of these inhibitors on TNFalpha production in microglial cells.Conclusions: These preliminary results suggest that both autophagy and general PI3K inhibition may selectively modulate the production of NO and other proinflammatory molecules in LPS-activated microglial cells