The inhibitory effect of trilinolein on norepinephrine-induced beta-myosin heavy chain promoter activity, reactive oxygen species generation, and extracellular signal-regulated kinase phosphorylation in neonatal rat cardiomyocytes.
The myocardial protective effects of trilinolein, isolated from the traditional Chinese herb Sanchi (Panax notoginseng), are thought to be related to its antioxidant activity. However, the intracellular mechanism underlying the protective effect of trilinolein in the heart remains unclear. In the present study, we investigated the effect of trilinolein on norepinephrine (NE)-induced protein synthesis in cardiomyocytes. Cultured neonatal rat cardiomyocytes were stimulated with NE, then protein content, [(3)H]-leucine incorporation, and beta-myosin heavy chain (beta-MyHC) promoter activity were examined. The effect of trilinolein on NE-induced intracellular reactive oxygen species (ROS) generation was measured with a redox- sensitive fluorescent dye (2',7'-dichlorofluorescin diacetate) and extracellular signal-regulated kinase (ERK) phosphorylation by Western blotting. Trilinolein inhibited NE-increased protein synthesis, beta-MyHC promoter activity, and intracellular ROS. Both trilinolein and the antioxidant, N-acetyl-cysteine, decreased NE- and H(2)O(2)-induced protein synthesis, beta-MyHC promoter activity, and ERK phosphorylation. These data indicate that trilinolein inhibits NE-induced protein synthesis via attenuation of ROS generation in cardiomyocytes.
Liu
Ju-Chi
JC
Graduate Institute of Medical Sciences, Taipei Medical University, Wan Fang Hospital, No. 111 Hsing-Lung Road, Sec. 3, Wen Shan District, Taipei 117, Taiwan, ROC.
Chan
Paul
P
Chen
Jin-Jer
JJ
Lee
Horng-Mo
HM
Lee
Wen-Sen
WS
Shih
Neng-Lang
NL
Chen
Yen-Ling
YL
Hong
Hong-Jye
HJ
Cheng
Tzu-Hurng
TH
D000111:Acetylcysteine / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D005456:Fluorescent Dyes / Q000378:metabolism; D016166:Free Radical Scavengers / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D015394:Molecular Structure; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D018995:Myosin Heavy Chains / Q000235:genetics* / Q000378:metabolism; D009638:Norepinephrine / Q000494:pharmacology*; D016877:Oxidants / Q000378:metabolism; D010084:Oxidation-Reduction; D010766:Phosphorylation; D011401:Promoter Regions, Genetic / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014280:Triglycerides / Q000737:chemistry / Q000494:pharmacology*; D024723:Ventricular Myosins / Q000235:genetics* / Q000378:metabolism
D005456:Fluorescent Dyes; D016166:Free Radical Scavengers; D016877:Oxidants; D017382:Reactive Oxygen Species; D014280:Triglycerides; D006861:Hydrogen Peroxide; D020928:Mitogen-Activated Protein Kinases; D024723:Ventricular Myosins; D018995:Myosin Heavy Chains; C009564:trilinolein; D000111:Acetylcysteine; D009638:Norepinephrine