Characteristics of electrophysiological changes in the process of astrocytes pyroptosis after hyperoxia exposure

To observe the electrophysiological changes of astrocytes in the process of hyperoxia induced apoptosis and analyze the relationship between electrophysiological characteristics and morphological changes.

Astrocytes were exposed to 90% hyperoxia for 12-72 h. The electrophysiological characteristics of astrocytes in each group were detected by patch clamp technique, and the morphological characteristics of astrocytes were observed at the same time. Then the same batch of astrocytes were collected, and the expression levels of caspase-1, caspase-3, gasdermin D (GSDMD) and gasdermin E (GSDME) were detected by Western blotting.

From 12 h to 72 h after hyperoxia exposure, the inward current was significantly lower than that of the control group (P<0.05), while the outward current was significantly decreased at 12 h and increased at 48 h (P<0.05). There was no significant difference between 24 h or 72 h after hyperoxia exposure and the control group (P>0.05). At each time point, the morphology of cells changed correspondingly. Western blotting showed that the expression of caspase-1 was increased significantly at 24 h and decreased significantly at 72 h after hyperoxia exposure (P<0.05); the expression of GSDMD was increased at 12 h and decreased gradually from 24 h to 72 h after hyperoxia exposure (P<0.05); the expression of caspase-3 did not change significantly at 12 h and 24 h after hyperoxia exposure (P>0.05), but began to decrease at 48 h (P<0.05); GSDME increased gradually at 24 h after hyperoxia exposure (P<0.05).

Under hyperoxia exposure, the ion channels of astrocytes are damaged, which can maintain the dysfunction of ion homeostasis, activate GSDME, induce the damaged cells to break away from the apoptotic pathway, and mediate the pyroptosis.