Effect of integrin β8 on TGF-β1 activation in astrocytes with oxygen glucose deprivation

Abstract:

Objective To study the effect of β₈ expression on transforming growth factor β1(TGF-β1) activation in astrocytes with oxygen glucose deprivation (OGD). Methods Astrocytes were cultured and then subjected to OGD to generate hypoxia-ischemia (HI) model in vitro. Immunocytochemistry was used to detect the expression and distribution of β₈ in nomoxia cultured cells. β₈ protein expression was quantified by Western blot at 12 hours, 1 day and 2 days after OGD. Astrocytes and luciferase reporter cells (TMLC) were co-cultured. β₈ RNA interference system was established to specifically inhibit β₈ expression in cultured astrocytes. TGF-β1 activation was then detected in the co-culture system. Results β₈ was mainly located in the cytoplasm and neurites of astrocytes. OGD resulted in increase of β₈ protein expression at 12 hours after reoxygenation in astrocytes, which was peaked at 1 day after reoxygenation. TGF-β1 activation was in accordance with β₈ expression in astrocyte-TMLC co-culture system after reoxygenation. After the inhibition of β₈, TGF-β1 activation was significantly reduced in all time points. Conclusions The highly expressed β₈ plays important roles in the regulation of TGF-β1 activation in neonatal rats with hypoxic-ischemic brain damage.