JOURNAL OF CARDIOVASCULAR PHARMACOLOGY
·
2022
·Vol. 80
·期 5
·679-689
·
IF 3.271
Wang Na,Yang Yang,Wen Jing,Fan Xin-Rong,Li Jian,Xiong Bing,Zhang Jin,Zeng Bo,Shen Jian-Wu,Chen Gui-Lan
Tolterodine is a first-line antimuscarinic drug used to treat overactive bladder. Adverse cardiac effects including tachycardia and palpitations have been observed, presumably because of its inhibition of the Human Ether-à-go-go-Related gene (hERG) K+ channel.
However, the molecular mechanism of hERG channel inhibition by tolterodine is largely unclear. In this study, we performed molecular docking to identify potential binding sites of tolterodine in hERG channel, and two-microelectrode voltage-clamp to record the currents of hERG and its mutants
expressed in Xenopus oocytes. The results of computational modeling demonstrated that phenylalanine at position 656 (F656) and tyrosine at position 652 (Y652) on the S6 helix of hERG channel are the most favorable binding residues of tolterodine, which was validated by electrophysiological
recordings on Y652A and F656A hERG mutants. The Y652A and F656A mutations decreased inhibitory potency of tolterodine 345-fold and 126-fold, respectively. The Y652A mutation significantly altered the voltage dependence of channel inhibition by tolterodine. For both the wild-type and the mutant
channels, tolterodine reduced the currents in a time-dependent manner, and the blockade occurred with the channel activated. Tolterodine did not interfere with hERG channel deactivation, whereas channel inactivation greatly impaired its blocking effect. The inhibition of hERG channel by tolterodine
is independent of its action on muscarinic acetylcholine receptors. In conclusion, tolterodine is an open-state blocker of hERG K+ channel with nanomolar potency. Y652 and F656, 2 aromatic residues on the inner S6 helix, are responsible for the high-affinity binding of tolterodine
to hERG channel.
研究领域:
药理学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
BIOMEDICINE & PHARMACOTHERAPY
·
2024
·
IF 6.9
Ying Xun Zhou,Wen Ping Wang,Jin Ke,Hui Ping Ou,Lin Yun Chen,An Guo Hou,Peng Li,Yun Shu Ma,Wen Bin Jin
Dysfunction of the Nav1.5, Cav1.2, and Kv channels could interfere with the AP and result in arrhythmias and even heart failure. We herein present a novel library of nuciferine analogs that target ion channels for the treatment of arrhythmias. Patch clamp measurements of ventricular myocytes revealed that 6a dramatically blocked both the I Na and I Ca without altering the current voltage relationship (including the activation potential and peak potential), accelerated the inactivation of Nav and Cav channels and delayed the resurrection of these channels after inactivation. Additionally, 6a significantly decreased the APA and RMP without affecting the APD30 or APD50. The IC 50 values of 6a against Nav1.5 and Cav1.2 were 4.98 μM and 4.62 μM, respectively. Furthermore, 6a (10 μM) blocked I Ks , I K1 , and I to with values of 17.01 %±2.54 %, 9.09 %±2.78 %, and 11.15 %±3.52 %, respectively. Surprisingly, 6a weakly inhibited hERG channels, suggesting a low risk of proarrhythmia. The cytotoxicity evaluation of 6a with the H9c2 cell line indicated that this compound was noncytotoxic. In vivo studies suggested that these novel nuciferine analogs could shorten the time of arrhythmia continuum induced by BaCl 2 and normalize the HR, QRS, QT and QTc interval and the R wave amplitude. Moreover, 6a dose-dependently affected aconitine-induced arrhythmias and notably improved the cumulative dosage of aconitine required to evoke VP, VT, VF and CA in rats with aconitine-induced arrhythmia. In conclusion, nuciferine analogs could be promising ion channel blockers that could be further developed into antiarrhythmic agents.
研究领域:
药理学
·
心血管病学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF MEDICINAL CHEMISTRY
·
2023
·
IF 6.7
Yang Wang,Ruiqi Su,Jianwen Chen,Xuan Liu,Jingning Luo,Yaoqiang Lao,Ping Huang,Jinguo Shi,Caibao Jiang,Liping Liao,Jingxia Zhang
Acute ischemic stroke (AIS) is a serious cardiovascular and cerebrovascular disease; Oxidative stress and neuroinflammation are important factors which destroy blood-brain barrier (BBB) in AIS. In the study, a series of 1,3,5-triphenyl-1,2,4-triazole derivatives were designed and synthesized; the optimal compound 9 was obtained by screening their anti-oxidant and anti-inflammatory effects; the neuroprotection effect of compound 9 was evaluated with a rat middle cerebral artery occlusion (MCAO) model. Subsequently, the mechanism of neuroprotection were explored via Western blot. The results prompt compound 9 maybe exert anti-AIS neuroprotection by inhibiting oxidative stress and neuroinflammation inhibition by inhibiting Keap1, COX-2 and iNOS. At the same time, it can protect BBB by reducing glycocalyx degradation and matrix metallopeptidase-9 levels. Its LD 50 > 1000 mg/kg on mice and hERG channel inhibition IC 50 > 30 μM, which lower acute toxicity and hERG channel inhibition would make compound 9 a promising stroke treatment candidate.
研究领域:
药理学
·
神经科学
·
心血管疾病
·
药物发现
✓ 已验证
DOI
PubMed
高影响因子
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