Upregulation of Transient Receptor Potential Vanilloid Type-1 Channel Activity and Ca2+ Influx Dysfunction in Human Pterygial Cells
Upregulation of Transient Receptor Potential Vanilloid Type-1 Channel Activity and Ca2+ Influx Dysfunction in Human Pterygial Cells
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DOI：
10.1167/iovs.16-19170
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发表时间：
2016-05-01
影响因子：
4.4
通讯作者：
Mergler, Stefan
中科院分区：
文献类型：
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作者：
Garreis, Fabian;Schroeder, Antje;Mergler, Stefan
目的.热敏瞬时受体电位香草酸1型（TRPV 1）通道（即，辣椒素[CAP]受体）在许多癌症中上调。本研究确定了这种反应是否发生在新鲜和培养的增生性人类外阴上皮组织。逆转录酶PCR和实时定量PCR，沿着免疫组织化学和蛋白质印迹，表征了TRPV 1在结膜和健康结膜组织、原代和永生化结膜细胞（hPtEC）以及原代和永生化结膜上皮细胞（HCjEC）中的表达模式。Ca2+成像和平面全细胞膜片钳评估TRP通道活性。MTS测定测量细胞代谢活性，并且细胞生长测定监测增殖。辣椒素（20 μ M）和将浴温升高到438 ℃以上在hPtEC中比在HCjEC中更多地激活Ca2+瞬变。辣椒素引起的内向电流的相应变化，抑制20 μ M辣椒平（CPZ）。血管内皮生长因子（VEGF）也增加了Ca2+内流，并诱导相应的内向电流hPtEC比HCjEC，而CPZ（20 μ M），BCTC（20 μ M），或镧（500 μ M）减少这些反应，分别。而表皮生长因子（EGF）增加增殖hPtEC比HCjEC，VEGF对这种反应没有影响。Capsazepine可抑制EGF和VEGF诱导的hPtEC增殖，但对HCjEC有细胞毒性。对EGF和VEGF的促有丝分裂反应通过TRPV1反式激活介导。只有在hPtEC中，EGF诱导的增殖增加超过HCjEC。因此，TRPV1是一个潜在的药物靶点，其在治疗翼状胬肉中的临床意义值得进一步评估。
PURPOSE. The heat-sensitive transient receptor potential vanilloid type-1 (TRPV1) channel (i.e., capsaicin [CAP] receptor) is upregulated in numerous cancers. This study determined if this response occurs in fresh and cultured hyperplastic human pterygial epithelial tissues.METHODS. Reverse transcriptase PCR and quantitative real-time PCR, along with immunohistochemistry and Western blotting, characterized TRPV1 expression patterns in pterygial and healthy conjunctival tissue, primary and immortalized pterygial cells (hPtEC), and primary and immortalized conjunctival epithelial cells (HCjEC). Imaging of Ca2+ and planar whole-cell patch-clamping evaluated TRP channel activity. An MTS assay measured cell metabolic activity and a cell growth assay monitored proliferation.RESULTS. Capsaicin (20 mu M) and elevating bath temperature above 438C activated Ca2+ transients more in hPtEC than HCjEC. Capsaicin induced corresponding changes in inward currents that were inhibited by 20 mu M capsazepine (CPZ). Vascular endothelial growth factor (VEGF) also increased Ca2+-influx and induced corresponding inward currents more in hPtEC than in HCjEC, whereas CPZ (20 mu M), BCTC (20 mu M), or La3+ (500 mu M) reduced these responses, respectively. Whereas epidermal growth factor (EGF) increased proliferation more in hPtEC than in HCjEC, VEGF had no effect on this response. Capsazepine suppressed hPtEC proliferation induced by EGF and VEGF, whereas it was cytotoxic to HCjEC.CONCLUSIONS. Mitogenic responses to EGF and VEGF are mediated through TRPV1 transactivation. Only in hPtEC do the increases in proliferation induced by EGF exceed those in HCjEC. Therefore, TRPV1 is a potential drug target whose clinical relevance in treating pterygium warrants further assessment.