Cardiology Department, Lotung Poh-Ai Hospital, Yilan County, 265, Taiwan; Cardiovascular Division, Fu Jen Catholic University Hospital, Fu Jen Catholic University, New Taipei City, 24352, Taiwan.
Division of Cardiology, Department of Internal Medicine, Kiang Wu Hospital, Macau.
Biochem Biophys Res Commun. 2020 May 21;526(1):117-121. doi: 10.1016/j.bbrc.2020.03.078. Epub 2020 Mar 17.
Tannic acid (TA) is a polyphenol compound present in wines and many beverages. Although previous works have shown that TA could cause vasodilation in an endothelial cell (EC)-dependent manner, there is hitherto no report showing whether TA could raise EC cytosolic Ca concentration. In this work we examined the effects of TA on cytosolic Ca of mouse brain bEND.3 EC. TA (1-30 μM) caused a slow elevation in cytosolic Ca level in a concentration-dependent manner. At 30 μM, TA triggered Ca influx without causing intracellular Ca release. TA-triggered Ca influx was suppressed by Ni (a non-specific Ca channel blocker), ruthenium red and SKF 96365 (non-specific TRP channel blockers), CBA (a selective TRPM4 inhibitor) and M 084 (a selective TRPC4/C5 blocker). However, TA-triggered Ca influx pathway was not permeable to Mn. Our results suggest TA activated TRP channels, possibly TRPM4 and TRPC4/C5, to promote influx of Ca.
单宁酸（TA）是一种存在于葡萄酒和许多饮料中的多酚化合物。虽然以前的研究表明 TA 可以通过内皮细胞（EC）依赖性方式引起血管舒张，但目前尚无报道表明 TA 是否可以提高 EC 胞浆 Ca 浓度。在这项工作中，我们研究了 TA 对小鼠脑 bEND.3 EC 胞浆 Ca 的影响。TA（1-30 μM）以浓度依赖性方式引起胞浆 Ca 水平的缓慢升高。在 30 μM 时，TA 触发 Ca 内流而不引起细胞内 Ca 释放。TA 触发的 Ca 内流被 Ni（非特异性 Ca 通道阻滞剂）、钌红和 SKF 96365（非特异性 TRP 通道阻滞剂）、CBA（选择性 TRPM4 抑制剂）和 M 084（选择性 TRPC4/C5 阻滞剂）抑制。然而，TA 触发的 Ca 内流途径对 Mn 是不可渗透的。我们的结果表明 TA 激活了 TRP 通道，可能是 TRPM4 和 TRPC4/C5，以促进 Ca 的内流。
