Neuroprotective Function of TNFAIP3 Interacting Protein 2 Against Oxygen and Glucose Deprivation/Reoxygenation-Induced Injury in Hippocampal Neuronal HT22 Cells Through Regulation of the TLR4/MyD88/NF-κB Pathway

BACKGROUND: Tumor necrosis factor-α (TNF-α)-induced protein 3-interacting protein 2 (TNIP2) has been well demonstrated to act as a principal contributor to the development of inflammatory diseases; however, the role of TNIP2 in cerebral ischemic/reperfusion injury has never been studied. METHODS: Gene expression was examined by using quantitative real-time polymerase chain reaction and Western blot. The functional role of TNIP2 in oxygen and glucose deprivation/reoxygenation (OGD/R)-induced neuronal injury was evaluated using cell counting kit-8, terminal deoxynucleotidyl transferase dutp nick end labeling assay and enzyme-linked immunosorbent assay. Commercial kits were applied to evaluate the activity of NF-kappa-B (NF-κB) and caspase-3, as well as the release of lactate dehydrogenase release (LDH). RESULTS: TNIP2 expression was substantially declined in HT22 cells following OGD/R stimulation. TNIP2 overexpression attenuated ODG/R-induced inflammation in HT22 cells, as evidenced by reduced levels of TNF-α, interleukin (IL)-1β, and intercellular cell adhesion molecule-1 (ICAM-1), and increased levels of IL-10. TNIP2 overexpression also reduced activity of NF-κB under ODG/R condition. Meanwhile, OGD/R treatment caused a reduction of cell viability and an elevation of cell apoptosis in HT22 cells, as indicated by the increase in LDH and caspase-3 activity. Whereas, OGD/R-induced HT22 cell injury was mitigated by TNIP2 overexpression in HT22 cells. Besides, we found the involvement of toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/NF-κB pathway in the neuroprotective effect of TNIP2 on OGD/R-induced HT22 cell damage. CONCLUSION: TNIP2 overexpression mitigates OGD/R-induced inflammatory response and apoptosis. Moreover, TLR4/MyD88/NF-κB pathway participates in the protective effect of TNIP2 on OGD/R-induced neuronal damage.