title: Effect of the total saponins of Aralia elata (Miq) Seem on cardiac contractile function and intracellular calcium cycling regulation.
abstract: BACKGROUND
  Total saponins of Aralia elata (Miq) Seem (AS) from the Chinese traditional herb Longya Aralia chinensis L. can improve cardiac function, although the active mechanism remains poorly understood. The present study aimed to determine the direct effect of AS on cardiac function in dogs and the effects on Ca2+ transient and contractions in isolated rat cardiomyocytes.
  
  
  METHODS
  In anesthetized dogs, hemodynamic indexes and myocardial oxygen consumption were determined before and after AS was administered. In isolated adult rat cardiomyocytes, contractile and intracellular Ca2+ properties were determined simultaneously in real time by using an IonOptix MyoCam system.
  
  
  RESULTS
  Our results showed that AS directly induced a positive inotropic effect and improved coronary blood flow and energy metabolism, indicating that AS induced a beneficial effect to treat myocardial ischemia/reperfusion injury. Moreover, AS increased sarcomere shortening, maximal velocity of shortening/relengthening (±dL/dt), amplitude of [Ca2+]i transients and SERCA activity in a concentration-dependent manner. PKCε was also activated after the cells were treated with AS.
  
  
  CONCLUSIONS
  These findings revealed the positive inotropic effect of AS on canine myocardium and isolated rat cardiomyocytes. This effect was possibly associated with an increase in amplitude of the [Ca2+]i transient and PKCε-dependent signaling pathway.
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China.
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Xu
authors.affiliation: Academy of Chinese Medical Sciences of Jilin Province, Gongnongda road 1745, Changchun 130021, Jilin, PR China.
authors.forename: Huibo
authors.initials: H
authors.lastname: Xu
authors.affiliation: Academy of Chinese Medical Sciences of Jilin Province, Gongnongda road 1745, Changchun 130021, Jilin, PR China.
authors.forename: Fuchun
authors.initials: F
authors.lastname: Wen
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China.
authors.forename: Xiaopo
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China.
authors.forename: Hong
authors.initials: H
authors.lastname: Sun
authors.affiliation: School of Biological Sciences, University of Edinburgh, King׳s Buildings, Edinburgh EH9 3JU, UK.
authors.forename: Fan
authors.initials: F
authors.lastname: Yao
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China. Electronic address: sunguibo@126.com.
authors.forename: Guibo
authors.initials: G
authors.lastname: Sun
authors.affiliation: Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine, Ministry of Education, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100193, PR China. Electronic address: sunsubmit@163.com.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Sun
mesh_terms: D000818:Animals; D027983:Aralia / Q000737:chemistry*; D002118:Calcium / Q000378:metabolism; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D004734:Energy Metabolism / Q000187:drug effects; D005260:Female; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D051744:Protein Kinase C-epsilon / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012503:Saponins / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D012503:Saponins; D051744:Protein Kinase C-epsilon; D002118:Calcium
keywords: Cardiomyocyte; Intracellular calcium concentration; Positive inotropic effect (PIE); Total saponins