PARP1 and necrotizing enterocolitis: In addition, we monitored the dynamic changes of PARP1 and PAR protein expression within 12 h of NEC induction, and Western blot analysis demonstrated that following the induction of NEC, the expression levels of PARP1 and PAR proteins increased initially and then decreased, reaching the peak level at 6 h post NEC induction (Supplementary Fig. 2A–C).