Organic Cation Transporter 1 and 3 Contribute to the High Accumulation of Dehydrocorydaline in the Heart
Organic Cation Transporter 1 and 3 Contribute to the High Accumulation of Dehydrocorydaline in the Heart
复制标题
有机阳离子转运蛋白 1 和 3 有助于脱氢紫堇碱在心脏中的大量积累
DOI：
10.1124/dmd.120.000025
复制
发表时间：
2020-10-01
影响因子：
3.9
通讯作者：
Zhou, Hui
中科院分区：
文献类型：
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作者：
Chen, Yingchun;Li, Cui;Zhou, Hui
脱氢紫堇碱（DHC）是延胡索的主要活性成分之一，是治疗冠心病的重要药物。我们之前的研究表明，口服延胡索提取物或 DHC 后，小鼠心脏中未结合的 DHC 浓度高于血浆，但潜在的吸收机制仍不清楚。在我们的研究中，我们研究了DHC在转基因细胞、原代新生大鼠心肌细胞和动物实验中的转运机制。利用实时定量聚合酶链反应和蛋白质印迹，我们发现小鼠心脏中表达的摄取转运蛋白包括有机阳离子转运蛋白1/3（OCT1/3）和肉碱/有机阳离子转运蛋白1/2（OCTN1/2）。转染细胞中的积累实验表明，DHC是OCT1和OCT3的底物，其K-m分别为11.29+/-3.3和8.96+/-3.7μM，但不是OCTN1/2的底物。此外，在 MDCK-MDR1 细胞中观察到的 DHC 流出水平（MDCK 模拟细胞的 1.71 倍）高于 MDCK 模拟细胞。因此，DHC 是 MDR1 的弱底物。使用原代新生大鼠心肌细胞的研究表明，OCT1/3抑制剂（奎尼丁、decynium-22和左旋四氢延胡索乙素）可阻止DHC的积累，而OCTN2抑制剂（米屈膦酸钠和I-肉碱）则不影响其积累。此外，联合使用 OCT1/3 抑制剂（左旋四氢延胡索乙素，THP）可降低小鼠心脏中 DHC 的浓度。基于这些发现，DHC可能部分由OCT1/3转运蛋白积累，并由心脏中的MDR1排出。 THP可以在DHC在小鼠心脏中的分布之后。意义声明我们报道了脱氢紫堇碱的心脏转运机制，在口服延胡索提取物或仅口服脱氢紫堇碱后，高度分布到心脏。脱氢紫堇碱（OCT1/3 和 MDR1 底物）在原代心肌细胞中的积累可能与 OCT1/3 的转运活性有关。这种能力受到选择性抑制剂（左旋四氢巴马汀，一种 OCT1/3 抑制剂）的阻碍，导致心脏对脱氢紫堇碱的暴露量减少近 40%。这些结果表明 OCT1/3 可能有助于心脏中脱氢紫堇碱的摄取。
Dehydrocorydaline (DHC), one of the main active components of Corydalis yanhusuo, is an important remedy for the treatment of coronary heart disease. Our previous study revealed a higher unbound concentration of DHC in the heart than plasma of mice after oral administration of C. yanhusuo extract or DHC, but the underlying uptake mechanism remains unelucidated. In our investigations, we studied the transport mechanism of DHC in transgenic cells, primary neonatal rat cardiomyocytes, and animal experiments. Using quantitative real-time polymerase chain reaction and Western blotting, we found that uptake transporters expressed in the mouse heart include organic cation transporter 1/3 (OCT1/3) and carnitine/organic cation transporter 1/2 (OCTN1/2). The accumulation experiments in transfected cells showed that DHC was a substrate of OCT1 and OCT3, with K-m of 11.29 +/- 3.3 and 8.96 +/- 3.7 mu M, respectively, but not a substrate of OCTN1/2. Additionally, a higher efflux level (1.71-fold of MDCK-mock) of DHC was observed in MDCK-MDR1 cells than in MDCK-mock cells. Therefore, DHC is a weak substrate for MDR1. Studies using primary neonatal rat cardiomyocytes showed that OCT1/3 inhibitors (quinidine, decynium-22, and levo-tetrahydropalmatine) prevented the accumulation of DHC, whereas OCTN2 inhibitors (mildronate and I-carnitine) did not affect its accumulation. Moreover, the coadministration of OCT1/3 inhibitors (levo-tetrahydropalmatine, THP) decreased the concentration of DHC in the mouse heart. Based on these findings, DHC may be accumulated partly by OCT1/3 transporters and excreted by MDR1 in the heart. THP could after the distribution of DHC in the mouse heart.SIGNIFICANCE STATEMENTWe reported the cardiac transport mechanism of dehydrocorydaline, highly distributed to the heart after oral administration of Corydalis yanhusuo extract or dehydrocorydaline only. Dehydrocorydaline (an OCT1/3 and MDR1 substrate) accumulation in primary cardiomyocytes may be related to the transport activity of OCT1/3. This ability, hampered by selective inhibitors (levo-tetrahydropal-matine, an inhibitor of OCT1/3), causes a nearly 40% reduction in exposure of the heart to dehydrocorydaline. These results suggest that OCT1/3 may contribute to the uptake of dehydrocorydaline in the heart.