title: Addition of strawberries to the usual diet decreases resting chemiluminescence of fasting blood in healthy subjects-possible health-promoting effect of these fruits consumption.
abstract: OBJECTIVE
  Regular strawberry consumption augmented plasma antioxidant activity and decreased lipid peroxidation suggests preventive potential of these fruits against oxidative stress-dependent disorders. Blood phagocytes are important source of oxidants that may contribute to systemic oxidative stress. We examined the effect of strawberry consumption on the luminol enhanced whole blood chemiluminescence (LBCL) reflecting oxidants generation by circulating phagocytes in healthy subjects.
  
  
  METHODS
  Thirty-one healthy subjects (being on their usual diet) consumed 500 g of strawberry pulp daily (between 11.00-14.00) for 30 days (1st strawberry course) and after 10 day wash-out the cycle was repeated (2nd strawberry course). Fasting blood and spot morning urine samples were collected before and after each strawberry course for measuring resting and agonist (fMLP)-induced LBCL, various phenolics and plasma antioxidant activity. Twenty subjects served as a control in respect to LBCL changes over the study period.
  
  
  RESULTS
  Strawberry consumption decreased median resting LBCL and this effect was more evident after the 1st course (by 38.2%, p < 0.05) than after the the 2nd one (18.7%), while fMLP-induced LBCL was constant. No changes in LBCL were noted in controls. Strawberries increased fasting plasma levels of caffeic acid and homovanillic acid as well as urolithin A and 4-hydroxyhippuric acid in spot urine. Plasma antioxidant activity and the number of circulating phagocytes did not change over the study period. Resting LBCL correlated positively with the number of circulating polymorphonuclear leukocytes at all occasions and negative correlation with plasma 4-hydroxyhippuric acid was noted especially after the first strawberry course (r = -0.46, p < 0.05).
  
  
  CONCLUSIONS
  The decrease in resting LBCL suggests that regular strawberry consumption may suppress baseline formation of oxidants by circulating phagocytes. This may decrease the risk of systemic imbalance between oxidants and anti-oxidants and be one of mechanisms of health-promoting effect of these fruits consumption.
authors.affiliation: a Department of Sleep Medicine and Metabolic Disorders , Medical University of Lodz , Lodz , POLAND.
authors.forename: Piotr
authors.initials: P
authors.lastname: Bialasiewicz
authors.forename: Anna
authors.initials: A
authors.lastname: Prymont-Przyminska
authors.forename: Anna
authors.initials: A
authors.lastname: Zwolinska
authors.forename: Agata
authors.initials: A
authors.lastname: Sarniak
authors.forename: Anna
authors.initials: A
authors.lastname: Wlodarczyk
authors.forename: Maciej
authors.initials: M
authors.lastname: Krol
authors.forename: Jovana
authors.initials: J
authors.lastname: Glusac
authors.forename: Piotr
authors.initials: P
authors.lastname: Nowak
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Markowski
authors.forename: Krzysztof P
authors.initials: KP
authors.lastname: Rutkowski
authors.forename: Dariusz
authors.initials: D
authors.lastname: Nowak
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D003374:Coumarins / Q000097:blood; D004032:Diet; D005260:Female; D031985:Fragaria; D005638:Fruit; D006293:Health Promotion; D064368:Healthy Volunteers; D006626:Hippurates / Q000097:blood; D006719:Homovanillic Acid / Q000097:blood; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D049449:Luminescence; D008163:Luminescent Measurements; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects; D010586:Phagocytes / Q000187:drug effects / Q000378:metabolism; D010636:Phenols / Q000097:blood / Q000652:urine; D017382:Reactive Oxygen Species / Q000378:metabolism
chemical_list: D000975:Antioxidants; D003374:Coumarins; D006626:Hippurates; D010636:Phenols; D017382:Reactive Oxygen Species; C026423:3,8-dihydroxy-6H-dibenzo(b,d)pyran-6-one; C056283:4-hydroxyhippuric acid; D006719:Homovanillic Acid
keywords: bioactive compounds; diets; general nutrition; preventative nutrition and chronic disease; supplements and functional foods