HDAC8在坏死性小肠结肠炎中通过调控铁死亡及炎症反应发挥作用的机制研究OA

Objective To investigate the protective effect of histone deacetylase 8(HDAC8)inhibitor PCI-34051 on intestinal injury in a mouse model of necrotizing enterocolitis(NEC)and its relationship with ferroptosis,and to further validate the mechanism of HDAC8 in ferroptosis of intestinal epithelial cells through in vitro experiments.Methods Forty 8-11day-old male SPF-grade C57BL/6 mice were randomly divided into five groups(n=8 per group):a control group,an NEC group,an HDAC8 low-expression group(NEC+PCI-34051),an HDAC8 low-expression+Erastin group(NEC+PCI-34051+Erastin),and an NEC+Erastin group(8 mice per group).An NEC model was established by hypoxia-cold stress.The HDAC8 inhibitor PCI-34051(20 mg/kg)and/or ferroptosis inducer Erastin(40 mg/kg)were administered intraperitoneally once daily for 14 days.Intestinal histopathological changes,oxidative stress and inflammatory markers,expression of ferroptosis-related proteins(SLC7A11,GPX4,p53),and mitochondrial ultrastructure were detected.In parallel,in vitro experiments were conducted using the mouse intestinal epithelial cell line IEC-6,which were divided into a control group,an Erastin group,an HDAC8 low-expression group(PCI-34051),an HDAC8 over-expression group(ADV-HDAC8),and an HDAC8 low-expression+SLC7A11 knockdown group.The expression of HDAC8,SLC7A11,GPX4,and ACSL4 was detected by qRT-PCR and Western blot,and changes in cell viability were assessed.Results Com-pared with the control group,the NEC group exhibited intestinal structural disorder,significant inflammatory cell infiltration,decreased GSH(P＜0.001),elevated MDA,ROS,and Fe2+(P＜0.001),reduced SLC7A11 and GPX4 expression(P＜0.001),and increased p53(P＜0.001).The HDAC8 low-expression group showed significantly reduced intestinal tissue damage,increased GSH expression,decreased MDA,ROS,and Fe2+,increased SLC7A11 and GPX4 expression,and decreased p53(P＜0.001).Erastin intervention partially reversed the protective effect of PCI-34051.Consistent in vitro results demonstrated that Erastin induced ferroptosis in IEC-6 cells,HDAC8 inhibited the upregulation of SLC7A11 and GPX4 and enhanced cell viability,while HDAC8 overexpression or SLC7A11 knockdown both enhanced the ferroptotic phenotype(P＜0.001).Conclusion The HDAC8 inhibitor PCI-34051 alleviates oxidative stress,inflammatory response and mitochondrial damage in NEC mice and intestinal epithelial cells by upregulating SLC7A11/GPX4 and inhibiting the p53 signaling pathway.Its protective effect is closely related to the inhibition of ferroptosis.