Objective: To discover the mechanism behind ameliorative effects of Michelia champaca(M. champaca) in gastrointestinal, respiratory and cardiovascular disorders. Methods: Antispasmodic potential was evaluated by tryin...Objective: To discover the mechanism behind ameliorative effects of Michelia champaca(M. champaca) in gastrointestinal, respiratory and cardiovascular disorders. Methods: Antispasmodic potential was evaluated by trying the M. champaca extract(aqueous:ethanolic) on rabbit aorta, trachea and jejunum in vitro. Isotonic and isometric transducers coupled with Power Lab data acquisition system was used to record the responses of isolated tissues. Results: M. champaca extract relaxed the spontaneous and high K^+(80 mmol/L)-induced contractions of isolated jejunum preparation of rabbit showing a Ca^(2+) channel blocking mechanism. Moreover, extract shifted calcium concentration response curves towards right like standard calcium channel blocker verapamil. In rabbit tracheal preparation, M. champaca relaxed both carbachol(1 μmol/L) and high K^+-induced contractions, likewise verapamil. In rabbit aorta preparation, M. champaca relaxed phenylephrine(1 μmol/L) and high K^+-induced contractions similar to verapamil. Conclusion: M. champaca possesses spasmolytic, airways relaxant and vasodilator actions mediated perhaps due to blocking of Ca^(2+) channels, hence validating its therapeutic usage in diarrhea, asthma and hypertension.展开更多
The intracellular calcium ions(Ca^(2+)) act as second messenger to regulate gene transcription,cell proliferation, migration and death. Accumulating evidences have demonstrated that intracellular Ca^(2+)homeostasis is...The intracellular calcium ions(Ca^(2+)) act as second messenger to regulate gene transcription,cell proliferation, migration and death. Accumulating evidences have demonstrated that intracellular Ca^(2+)homeostasis is altered in cancer cells and the alteration is involved in tumor initiation, angiogenesis,progression and metastasis. Targeting derailed Ca^(2+)signaling for cancer therapy has become an emerging research area. This review summarizes some important Ca^(2+)channels, transporters and Ca^(2+)-ATPases,which have been reported to be altered in human cancer patients. It discusses the current research effort toward evaluation of the blockers, inhibitors or regulators for Ca^(2+)channels/transporters or Ca^(2+)-ATPase pumps as anti-cancer drugs. This review is also aimed to stimulate interest in, and support for researchinto the understanding of cellular mechanisms underlying the regulation of Ca^(2+)signaling in different cancer cells, and to search for novel therapies to cure these malignancies by targeting Ca^(2+)channels or transporters.展开更多
文摘Objective: To discover the mechanism behind ameliorative effects of Michelia champaca(M. champaca) in gastrointestinal, respiratory and cardiovascular disorders. Methods: Antispasmodic potential was evaluated by trying the M. champaca extract(aqueous:ethanolic) on rabbit aorta, trachea and jejunum in vitro. Isotonic and isometric transducers coupled with Power Lab data acquisition system was used to record the responses of isolated tissues. Results: M. champaca extract relaxed the spontaneous and high K^+(80 mmol/L)-induced contractions of isolated jejunum preparation of rabbit showing a Ca^(2+) channel blocking mechanism. Moreover, extract shifted calcium concentration response curves towards right like standard calcium channel blocker verapamil. In rabbit tracheal preparation, M. champaca relaxed both carbachol(1 μmol/L) and high K^+-induced contractions, likewise verapamil. In rabbit aorta preparation, M. champaca relaxed phenylephrine(1 μmol/L) and high K^+-induced contractions similar to verapamil. Conclusion: M. champaca possesses spasmolytic, airways relaxant and vasodilator actions mediated perhaps due to blocking of Ca^(2+) channels, hence validating its therapeutic usage in diarrhea, asthma and hypertension.
基金supported by NIH R01-CA185055(to Zui Pan)Chaochu Cui received postgraduate student training of internationalization level promotion program from Sun Yat-sen University(02300-52114000)
文摘The intracellular calcium ions(Ca^(2+)) act as second messenger to regulate gene transcription,cell proliferation, migration and death. Accumulating evidences have demonstrated that intracellular Ca^(2+)homeostasis is altered in cancer cells and the alteration is involved in tumor initiation, angiogenesis,progression and metastasis. Targeting derailed Ca^(2+)signaling for cancer therapy has become an emerging research area. This review summarizes some important Ca^(2+)channels, transporters and Ca^(2+)-ATPases,which have been reported to be altered in human cancer patients. It discusses the current research effort toward evaluation of the blockers, inhibitors or regulators for Ca^(2+)channels/transporters or Ca^(2+)-ATPase pumps as anti-cancer drugs. This review is also aimed to stimulate interest in, and support for researchinto the understanding of cellular mechanisms underlying the regulation of Ca^(2+)signaling in different cancer cells, and to search for novel therapies to cure these malignancies by targeting Ca^(2+)channels or transporters.
