[The role of histone deacetylases in the pathogenesis of idiopathic pulmonary fibrosis and cryptogenic organizing pneumonia]

Objective: To explore the role of histone deacetylases(HDAC) in the pathogenesis of idiopathic pulmonary fibrosis(IPF) and cryptogenic organizing pneumonia(COP). Methods: Fifteen IPF patients [14 males and 1female, age 40-73 years, mean age (59±8) years] and 15 COP patients [5 males and 10 females, age 41-71 years, mean age (59±8) years] from Peking Union Medical College Hospital were recruited from March 2018 to October 2018. Fifteen healthy donors[4 males and 11females, age 43-70 years, mean age (58±6) years] were enrolled as controls. Peripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation. The nuclear and cytoplasmic proteins were extracted by Nuclear Extraction Kit. HDAC activity was measured by fluorimetric method. The relations between HDAC activity and clinical parameters were analyzed with SPSS. Results: The HDAC activity of cytoplasmic protein and nuclear protein from patients with IPF were (724±216) nmol/L and (2 309±708) nmol/L, which were higher than that of health controls (409±105) nmol/L and (1 572±611) nmol/L (P<0.01 for both). So as to the HDAC activity of cytoplasmic protein and nuclear protein from patients with COP which were (718±245) nmol/L and (3 310±1 005) nmol/L (P<0.01 for both).The HDAC activity of nuclear protein from COP patients was higher than that from IPF patients (Z=-2.840, P=0.005). The HDAC activity of nuclear protein was negatively correlated with FEV(1) and D(L)CO in IPF patients (r=-0.574, P=0.025; r=-0.583, P=0.029), and negatively correlated with FVC and TLC in COP patients(r=-0.846, P=0.016; r=-0.900, P=0.015). Conclusion: HDAC may be involved in the pathogenesis of COP and IPF.