Objective: To investigate the expression changes of protein kinase C (PKC) and nuclear factor kappa B (NF-kappaB) in lung tissue of patients with chronic obstructive pulmonary disease (COPD).
Methods: The lung tissues obtained from 15 patients (A group) without COPD and 15 patients (B group) with COPD matched with A group in age and sex undergoing pneumonectomy for peripheral lung cancer. The protein and mRNA level of PKCalpha was determined by using Western blot analysis and reverse transcription polymerase chain reaction respectively. NF-kappaB p65 nuclei positive expression was observed by immunohistochemical technique. Electrophoretic mobility shift assay was used to detect the NF-kappaB/DNA binding activity.
Results: (1) Forced expiratory volume in one second (FEV1)/forced vital capacity (FVC), FEV1(%Pre) and partial pressure of oxygen in artery (PaO2) of B group were significantly lower than that of A group (t=7.73-13.96, P <0.01, respectively). (2) There was higher level of PKCalpha/GAPDH mRNA and the relative expression of PKCalpha protein in B group than in A group (t=7.64 and 22.27, P <0.01, respectively). (3) There were significant increases in NF-kappaB p65 nuclei positive expression of B group than that of A group (t=112.79, P <0.01). The NF-kappaB/DNA binding activity of B group was approximately 3.2-fold that of A group (t=104.80, P <0.01). (4) There was a significant negative correlation between PaO2 and the nuclei positive expression rate of NF-kappaB p65 in 15 cases of B group (r=-0.7090, P <0.05).
Conclusion: The expression of PKCalpha, NF-kappaB p65 nuclei positive expression rate and NF-kappaB/DNA binding activity significantly increase in lung tissues of patients with COPD, suggesting that the activation of PKC and NF-kappaB may contribute to the process of COPD in human.