Effects of Xiaoqinglong decoction on gene expression profiles in a rat chronic obstructive pulmonary disease model

Xiaoqinglong decoction (XQLD) has been used for centuries in Asia to effectively treat patients with chronic obstructive pulmonary disease (COPD). However, its mechanisms remain unknown. To elucidate this problem, we analyzed the effects of XQLD on gene expressions profiles in COPD rats. In the study, 20 male Wistar rats were injected with lipopolysaccharide (LPS), exposed to cigarette smoke and kept at -20°C for 5 min/day for a successive 8 days to establish COPD animals. Trachea ultramicrostructure and histomorphology were observed to determine whether these models were established successfully. Gene expression profiles were detected using cDNA microarrays. We found 56 differentially expressed genes associated with COPD progression, including 32 up-regulated genes and 24 down-regulated genes. These genes were confirmed to be involved in immune and inflammation reactions, metabolism, cell transportation and the cell cycle, signal transduction and gene regulation. Comparison of gene expression between the therapy group and control group showed that there were only 11 differentially expressed genes, including 5 up-regulated genes and 6 down-regulated genes. We concluded that XQLD had therapeutic effects in COPD rats by affecting gene expression. Pharmacological or targeted expression of some genes might be found useful as novel therapy in COPD management.