Connections of annexin A1 and translocator protein-18 kDa on toll like receptor stimulated BV-2 cells

Author(s)

Pantaleao, Lorena ^[1] ; Oliveira Rocha, Gustavo Henrique ^[1] ; Reutelingsperger, Chris ^[2] ; Tiago, Manoela ^[1] ; Maria-Engler, Silvya Stucchi ^[1] ; Solito, Egle ^[3] ; Farsky, Sandra P. ^[1]

Affiliation

^[1] Univ Sao Paulo, Sch Pharmaceut Sci, Dept Clin & Toxicol Anal, Av Prof Lineu Prestes 580 Bl 13B, BR-05508900 Sao Paulo - Brazil

^[2] Maastricht Univ, Cardiovasc Res Inst Maastricht, Dept Biochem, 616 6200 MD, NL-6211 CH Maastricht - Netherlands

^[3] Queen Mary Univ, William Harvey Res Inst, Sch Med & Dent, Charterhouse Sq, London EC1M 6BQ - England

• Document type: Journal article
• Source: Experimental Cell Research; v. 367, n. 2, p. 282-290, JUN 15 2018.
• Web of Science Citations: 3

Abstract

Background: Annexin A1 (ANXA1) and Translocator Protein-18KDa (TSPO) down-regulate neuroinflammation. We investigated the role of recombinant ANXA1 (rANXA) on TSPO functions on Toll Like Receptor (TLR) activated microglia. Methods: BV-2 cells (murine microglia), were stimulated by E. coli Lipopolysaccharide (LPS) and treated with rANXA1 in order to measure TSPO expression and inflammatory parameters. Anti-sense ANXA1 and TLR4 and TSPO shRNA, as well as pharmacological treatments, were employed to assess the mechanisms involved. Results: LPS-stimulated BV-2 cells caused overexpression of TSPO, which was inhibited by: pharmacological blockade of TLR4 or TLR4 mRNA silencing; inhibition of myeloid differentiation primary response gene 88 (MyD88) dimerization; or blocking of nuclear factor kappa B (NF-kappa B) activation. rANXA1 treatment impaired LPS-induced TSPO upregulation by down-modulating MyD88 and NF-kappa B signaling; the effect was abolished by WRW4, an antagonist of formyl peptide receptor 2 (FPR2). rANXA1 treatment also downregulated interleukin 1 beta (IL-1 beta) and tumor necrosis factor-alpha (TNF alpha) secretion in LPS-stimulated BV-2 cells. TSPO knockdown in BV-2 cells augmented LPS-induced TNFa secretion and abolished the inhibitory effect of rANXA1 on TNF alpha secretion evoked by LPS. Conclusions: exogenous ANXA1 down-modulates LPS-induced TSPO via MyD-88/NF-kappa B pathways, and constitutive TSPO is pivotal for the control of ANXA1 on TNF alpha secretion. TSPO actions may be involved with the mechanisms of ANXA1 on inflammatory brain diseases. (AU)

• FAPESP's process: 14/07328-4 - Identification of endogenous pathways for the control of inflammation
• Grantee: Sandra Helena Poliselli Farsky
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 13/25903-3 - Annexin A1 modulation mechanism on the expression of the translocator protein (TSPO)
• Grantee: Lorena Do Nascimento Pantaleão
• Support Opportunities: Scholarships in Brazil - Doctorate