RESUMO
Chronic obstructive pulmonary disease (COPD) is a lung disease caused by an inflammatory response to various inhaled toxins, especially cigarette smoke. Reactive oxygen species (ROS) and epigenetic abnormality are intimately related to the pathology of COPD, and the overproduction of ROS results in a decrease of histone deacetylase 2 (HDAC2), leading to glucocorticoid resistance. Therefore, a novel treatment that simultaneously reduces ROS level and glucocorticoid resistance is urgently needed. In this study, we developed a codelivery system using core-shell type lipid-polymer nanoparticles (LPNs) composed of a poly(lactic acid) (PLA) core encapsulating a potent antioxidant Mn-porphyrin dimer (MnPD) and a cationic lipid (DOTAP) shell that binds HDAC2-encoding plasmid DNA (pHDAC2), as a new therapeutic approach toward COPD. The transfection of pHDAC2 combined with the elimination of ROS by MnPD exhibited a significant enhancement of intracellular HDAC2 expression levels, suggesting that the multi-antioxidative activity of MnPD plays a crucial role in the expression of HDAC2. Moreover, treatment with LPNs efficiently ameliorated the steroid resistance in COPD models in vitro as evidenced by the lowered expression levels of IL-8. Recovery from mitochondrial dysfunction may be the mechanism underlying the action of LPNs. The PLA-MnPD/DOTAP/pHDAC2 system proposed offers a new therapeutic approach for COPD based on the synergism of ROS elimination and HDAC2 expression.
