School of Pharmacy, China Medical University, Taichung, Taiwan.
Department of Anesthesiology, China Medical University Hospital, Taichung, Taiwan.
Clin Exp Pharmacol Physiol. 2018 Aug;45(8):788-796. doi: 10.1111/1440-1681.12929. Epub 2018 Mar 23.
Gossypol, a polyphenolic dialdehyde toxin isolated from cotton seed, has anti-cancer properties and has recently shown some success in the treatment of glioma. Its effects on brain neurons and blood vessels are poorly understood. In this work we examined the effects of gossypol on cytosolic Ca concentration ([Ca ] ) of mouse brain bEND.3 endothelial cells. Cell viability tests revealed that after 3 hour and 18 hour exposures, 10 µmol/L gossypol caused 23% and 65% cell death, respectively; 3 µmol/L gossypol caused no and 21% cell death, respectively. [Ca ] was raised concentration-dependently by 1-10 µmol/L gossypol. We then explored the Ca signalling triggered by 3 µmol/L gossypol, which inflicted minimal toxicity: the Ca signal was composed largely of Ca influx and to a small extent, intracellular Ca release. Such Ca influx was much larger than store-operated Ca influx triggered by maximal Ca pool depletion. The Ca influx triggered by 3 and 10 µmol/L gossypol caused NO release and cell death, respectively. Gossypol also triggered influx of Mn and Na , but not Ni and Co . Gossypol-triggered Ca signal was inhibited only by 14% and 37% by 100 µmol/L La and 10 µmol/L nimodipine, respectively; and not suppressed at all by 5 mmol/L Ni . Gossypol-triggered Ca signal was suppressed by 78% by 30 µmol/L ruthenium red, suggesting gossypol may act on TRPV channels. Our results suggest gossypol triggered opening of a non-selective cation pore, possibly a member of the TRPV family.
从棉籽中分离得到的多酚二醛毒素，毒扁豆碱具有抗癌特性，最近在治疗神经胶质瘤方面取得了一些成功。其对脑神经元和血管的影响知之甚少。在这项工作中，我们研究了毒扁豆碱对小鼠脑 bEND.3 内皮细胞胞浆游离钙浓度([Ca 2+ ] i )的影响。细胞活力测试表明，暴露 3 小时和 18 小时后，10 μmol/L 毒扁豆碱分别导致 23%和 65%的细胞死亡；3 μmol/L 毒扁豆碱分别导致 0 和 21%的细胞死亡。1-10 μmol/L 毒扁豆碱浓度依赖性地升高[Ca 2+ ] i 。然后，我们研究了由 3 μmol/L 毒扁豆碱触发的 Ca 信号，该浓度的毒扁豆碱引起的细胞毒性最小：该 Ca 信号主要由 Ca 内流组成，在较小程度上由细胞内 Ca 释放组成。这种 Ca 内流比最大 Ca 池耗竭触发的 STOC 大得多。3 和 10 μmol/L 毒扁豆碱引起的 Ca 内流分别导致 NO 释放和细胞死亡。毒扁豆碱还触发了 Mn 和 Na 的内流，但不触发 Ni 和 Co 的内流。100 μmol/L La 和 10 μmol/L 尼莫地平分别仅抑制毒扁豆碱触发的 Ca 信号 14%和 37%；5 mmol/L Ni 完全不抑制毒扁豆碱触发的 Ca 信号。30 μmol/L 钌红抑制毒扁豆碱触发的 Ca 信号 78%，提示毒扁豆碱可能作用于 TRPV 通道。我们的结果表明，毒扁豆碱触发了一种非选择性阳离子通道的开放，该通道可能是 TRPV 家族的一个成员。
