title: Preconditioning and acute effects of flavonoids in protecting cardiomyocytes from oxidative cell death.
abstract: While flavonoids can reportedly protect against cardiac ischemia-reperfusion injury, the relative effectiveness of different flavonoids and the mechanisms involved are unclear. We compared protection by different flavonoids using rat embryonic ventricular H9c2 cells subjected to simulated ischemia-reperfusion (IR) and to tert-butyl hydroperoxide (t-buOOH). Characterization of the IR model showed the relative contributions of glucose, serum, and oxygen deprivation to cell death. With long-term (2-3 day) pretreatment before IR the best protection was given by catechin, epigallocatechin gallate, proanthocyanidins, and ascorbate, which protected at all doses. Quercetin protected (34%) at 5 μM but was cytotoxic at higher doses. Cyanidin protected mildly (10-15%) at 5 and 20 μM, while delphinidin had no effect at 5 μM and was cytotoxic at higher doses. Comparing long-term and acute protection by catechin, a higher concentration was needed for benefit with acute (1 hr) pretreatment. With a pure oxidative stress (t-buOOH) only quercetin significantly protected with 3-day pretreatment, while with short-term (1 h) pretreatments protection was best with quercetin and epigallocatechin gallate. The results suggest catechins to be especially useful as IR preconditioning agents, while quercetin and epigallocatechin gallate may be the most protective acutely in situations of oxidative stress.
authors: College of Health and Nutrition, Shiraz University of Medical Sciences, Iran.
authors: Masoumeh
authors: M
authors: Akhlaghi
authors: Brian
authors: B
authors: Bandy
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology; D002316:Cardiotonic Agents / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D002392:Catechin / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D002460:Cell Line; D016895:Culture Media, Serum-Free; D019610:Cytoprotection / Q000187:drug effects*; D005419:Flavonoids / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D005947:Glucose / Q000494:pharmacology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000378:metabolism; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy / Q000473:pathology; D032383:Myocytes, Cardiac / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology*; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects*; D010100:Oxygen / Q000494:pharmacology; D011794:Quercetin / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D013997:Time Factors; D020122:tert-Butylhydroperoxide / Q000633:toxicity
chemical_list: D002316:Cardiotonic Agents; D016895:Culture Media, Serum-Free; D005419:Flavonoids; D002392:Catechin; D020122:tert-Butylhydroperoxide; D011794:Quercetin; C045651:epigallocatechin gallate; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D005947:Glucose; D001205:Ascorbic Acid; D010100:Oxygen