[Expression of mitogen-actived protein kinase, phosphatidylinositol 3-kinase and hypoxia-inducible factor-1alpha in pulmonary arteries of patients with chronic obstructive pulmonary disease].
OBJECTIVE
To investigate the expression of mitogen-actived protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K) and hypoxia-inducible factor-1alpha (HIF-1alpha) in pulmonary artery of chronic obstructive pulmonary disease (COPD), and therefore to explore the possible roles of MAPK, PI3K and HIF-1alpha in the development of hypoxia-induced pulmonary hypertension (HPH).


METHODS
Small pulmonary arterial remodeling was observed by morphometric analysis in surgically removed lung tissues from COPD patients and control patients treated for lung tumors. The expression of p-ERK, p-JNK, p-P38, p-PKB and HIF-1alpha in lung tissue was examined by in situ hybridization and immunohistochemistry.


RESULTS
Morphometry analysis showed that the ratio of wall area to total area (WA%) and pulmonary artery media thickness (PAMT) were increased in COPD patients [18 +/- 3, (31 +/- 3) microm] than in the control [30 +/- 5, (40 +/- 4) microm, t = 7.58, 6.57, all P < 0.01]. The expression levels of p-ERK protein, p-PKB protein, HIF-1alpha protein and HIF-1alpha mRNA level (absorbance, A) were significantly higher in pulmonary artery walls of COPD patients (0.164 +/- 0.012, 0.113 +/- 0.009, 0.232 +/- 0.008, 0.154 +/- 0.013, respectively) as compared to those of the control (0.062 +/- 0.010, 0.031 +/- 0.011, 0.058 +/- 0.006, 0.052 +/- 0.008, respectively, t = 23.18, 21.03, 62.14, 2.44, all P < 0.01), while p-JNK and p-P38 protein levels in the control group (0.048 +/- 0.013, 0.028 +/- 0.007, respectively) and COPD patients (0.041 +/- 0.012, 0.031 +/- 0.010, respectively, all P > 0.05) were barely positive. The expression of p-ERK, p-PKB and HIF-1alpha were negatively correlated with LA% (r = -0.920 - -0.892, all P < 0.05), and positively correlated with PAMT (r = 0.895 - 0.934, all P < 0.05).


CONCLUSIONS
Differential expression of p-ERK, p-PKB and HIF-1alpha may be involved in the occurrence of HPH in COPD patients.
Kong
Chun-chu
CC
Department of Respiratory Disease Research, Hunan Institute of Gerontology, Hunan Geriatric Hospital, Changsha 410001, China.
Dai
Ai-guo
AG
D000368:Aged; D005260:Female; D020869:Gene Expression Profiling; D006801:Humans; D000860:Hypoxia / Q000378:metabolism / Q000473:pathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism*; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism*; D029424:Pulmonary Disease, Chronic Obstructive / Q000378:metabolism* / Q000473:pathology; D015398:Signal Transduction
D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D019869:Phosphatidylinositol 3-Kinases; D020928:Mitogen-Activated Protein Kinases