Effect of TRPV1 Channel on Proliferation and Apoptosis of Airway Smooth Muscle Cells of Rats

• Published in: Journal of Huazhong University of Science and Technology. Medical sciences Vol. 34; no. 4; pp. 504 - 509
• Main Author: 赵丽敏 况红艳 张罗献 吴纪珍 陈献亮 张晓宇 马利军
• Format: Journal Article
• Language: English
• Published: Heidelberg Huazhong University of Science and Technology 01.08.2014; Department of Respiratory and Critical Care Medicine, Zhengzhou University People's Hospital, Zhengzhou 450003, China
• Subjects: Animals; Antipruritics - pharmacology; Apoptosis - physiology; Bronchi - cytology; Bronchi - metabolism; Calcium Signaling - drug effects; Calcium Signaling - physiology; Capsaicin - analogs & derivatives; Capsaicin - pharmacology; Cell Proliferation; Medicine; Medicine & Public Health; Myocytes, Smooth Muscle - cytology; Myocytes, Smooth Muscle - metabolism; Rats; Rats, Sprague-Dawley; TRPV Cation Channels - antagonists & inhibitors; TRPV Cation Channels - metabolism; 免疫荧光染色; 动脉平滑肌细胞; 大鼠; 气道重塑; 细胞凋亡; 细胞增殖; 逆转录聚合酶链反应; 钙通道; apoptosis; intracellular calcium; proliferation; transient receptor potential vanilloid 1; airway smooth muscle cells
• ISSN: 1672-0733; 1993-1352
• DOI: 10.1007/s11596-014-1306-0

Airway remodeling is an important pathological feature of asthma and the basis of severe asthma. Proliferation of airway smooth muscle cells （ASMCs） is a major contributor to airway remod- eling. As an important Ca2＋ channel, transient receptor potential vanilloid 1 （TRPV1） plays the key role in the cell pathological and physiological processes. This study investigated the expression and activity of TRPV1 channel, and further clarified the effect of TRPV1 channel on the ASMCs proliferation and apoptosis in order to provide the scientific basis to treat asthmatic airway remodeling in clinical practice Immunofluorescence staining and reverse transcription polymerase chain reaction （RT-PCR） were used to detect the expression of TRPVI in rat ASMCs. Intracellular Ca2＋ was detected using the single cell confocal fluorescence microscopy measurement loaded with Fluo-4/AM. The cell cycles were observed by flow cytometry. MTT assay and Hoechst 33258 staining were used to detect the proliferation and apoptosis of ASMCs in rats respectively. The data showed that： （1） TRPV1 channel was present in rat ASMCs. （2） TRPV1 channel agonist, capsaicin, increased the Ca2~ influx in a concentration-dependent manner （EC50=284.3＋58 nmol/L）. TRPV1 channel antagonist, capsazepine, inhibited Ca2＋ influx in rat ASMCs. （3） Capsaicin significantly increased the percentage of S＋G2M ASMCs and the absorbance of MTT assay. Capsazepine had the opposite effect. （4） Capsaicin significantly inhibited the apoptosis, whereas capsazepine had the opposite effect. These results suggest that TRPV1 is present and mediates Ca2＋ influx in rat ASMCs. TRPV1 activity stimulates proliferation of ASMCs in rats.