title: Hypolipidemic and antioxidant effects of hydroxycinnamic acids, quercetin, and cyanidin 3-glucoside in hypercholesterolemic erythrocytes (in vitro study).
abstract: OBJECTIVE
  Four polyphenols: ferulic acid and p-coumaric acid (hydroxycinnamic acids), quercetin (flavonol) and cyanidin 3-glucoside (anthocyanin) were selected, and their antioxidant properties and their influence on cholesterol concentration in hypercholesterolemic and normal erythrocytes were investigated.
  
  
  METHODS
  To determine the effect of phenolic compounds, we prospectively studied cholesterol concentration, lipid peroxidation and membranes fluidity. Whole-blood and isolated erythrocytes (2% hematocrit) were incubated for 24 h with selected compounds at concentration 1, 10 and 100 μmol/L. All investigated compounds decreased lipid peroxidation in whole blood. Cyanidin 3-glucoside and quercetin showed higher antioxidant properties than hydroxycinnamic acids (ferulic acid and p-coumaric acid).
  
  
  RESULTS
  Incubation of whole blood of hypercholesterolemic patients with quercetin and cyanidin 3-glucoside resulted in statistically significant reduction of cholesterol concentration in erythrocytes down to 75% (at 10 μmol/L of polyphenols) and 69% (at 100 μmol/L of polyphenols) of initial values. The effect of both compounds on isolated erythrocytes was even more pronounced, reduction down to 70% (at 10 μmol/L of polyphenols) and 58% (at 100 μmol/L of polyphenols) of initial values. After incubation of isolated erythrocytes of hypercholesterolemic patients with quercetin and cyanidin 3-glucoside, increase of membrane fluidity was noticed. After incubation of isolated erythrocytes of healthy donors with investigated compounds, no changes in membrane fluidity were observed.
  
  
  CONCLUSIONS
  Our results indicate that flavonols and anthocyanins have higher antioxidant properties and higher influence on cholesterol concentration in erythrocytes membranes than simple hydroxycinnamic acids.
authors.affiliation: Department of Environment Pollution Biophysics, University of Łódź, Łódź, Poland. duchno@biol.uni.lodz.pl
authors.forename: Piotr
authors.initials: P
authors.lastname: Duchnowicz
authors.forename: Marlena
authors.initials: M
authors.lastname: Broncel
authors.forename: Anna
authors.initials: A
authors.lastname: Podsędek
authors.forename: Maria
authors.initials: M
authors.lastname: Koter-Michalak
mesh_terms: D000872:Anthocyanins / Q000378:metabolism*; D000975:Antioxidants / Q000378:metabolism*; D002784:Cholesterol / Q000097:blood / Q000378:metabolism; D003373:Coumaric Acids / Q000378:metabolism; D019587:Dietary Supplements; D004910:Erythrocyte Membrane / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D005960:Glucosides / Q000378:metabolism*; D006801:Humans; D006937:Hypercholesterolemia / Q000097:blood*; D000960:Hypolipidemic Agents / Q000378:metabolism*; D015227:Lipid Peroxidation; D008297:Male; D008560:Membrane Fluidity; D008875:Middle Aged; D009994:Osmolar Concentration; D011422:Propionates; D011794:Quercetin / Q000378:metabolism*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D003373:Coumaric Acids; D005960:Glucosides; D000960:Hypolipidemic Agents; D011422:Propionates; D017392:Thiobarbituric Acid Reactive Substances; C462279:cyanidin-3-O-beta-glucopyranoside; D002784:Cholesterol; D011794:Quercetin; C004999:ferulic acid; C495469:p-coumaric acid