Polystyrene Targeting Nanoparticles’ Effect 
on Lung Injury in Severe Acute Pancreatitis

Background Severe acute pancreatitis (SAP) has an acute onset and critical condition. It can mainly cause a pulmonary infection in patients. Whether polystyrene targeting nanoparticles play a role in lung injury in SAP remain unclear. Purpose To evaluate polystyrene targeting nanoparticles’ (PTNs) effect on lung injury in severe acute pancreatitis (SAP). Materials and Methods Nanoparticles are characterized by a large unit surface area, high dispersion, tissue affinity, and adhesion, and are more conducive to bringing drugs into contact with tissues. In this study, SAP lung injury cells from alveolar lavage exfoliated cells under bronchoscopy were exposed to PTN to detect the proliferation of SAP lung injury cells, cycle and apoptosis, and nicotinamide adenine dinucleotide phosphate oxidase 2/reactive oxygen species/nuclear factor-kappa B (NOX2/ROS/NF-κB) expression. Results The compound PTN inhibited cell proliferation in SAP, and the degree of inhibition was positively correlated with the dose and the length of time. PTN inhibited the proliferation of SAP lung injury cells dose-dependently (5, 10, and 20 µmol/L) and arrested SAP lung injury cells in G2/M phase and increased cell apoptosis. In addition, PTN reduced NOX2, ROS, and NF-κB in SAP lung injury and downregulated interleukin-6, tumor necrosis factor-alpha, Janus kinase, signal transducer and activator of transcription, and interleukin-10 levels. Conclusion This study shows that polymer-targeted nano-drug systems regulate lung-damaged cell growth in SAP. PTN inhibits inflammation in SAP via regulation of NOX2/ROS/NF-κB.