title: Bioactivity of arid region honey: an in vitro study.
abstract: BACKGROUND
  Antioxidant and anti-inflammatory properties of honey have been largely recognized by various studies. Almost all of the potential benefits are associated with polyphenol content. Honey varieties from the arid region are reported to be rich in polyphenols, but data related to its bioactivity in vitro is greatly lacking. This study aimed at establishing the antioxidant and anti-inflammatory properties of arid region honey. Four honey varieties from arid region (H1, H2, H3, and H4) and two popular non-arid region honey (H5 and H6) were tested in vitro in this study.
  
  
  METHODS
  The erythrocyte membrane protection effect of honey varieties were measured by hemolysis assay after exposing erythrocytes to a peroxide generator. The subsequent production of MDA (malondialdehyde) content in erythrocytes was measured. Immunomodulatory effect of the honey varieties was tested in prostate cancer cells PC-3 and PBMC (peripheral blood mononuclear cells) by measuring the IL-6 (interleukin 6) and NO (nitric oxide) levels in cell culture supernatant after incubation with the honey varieties. PC-3 cell viability was assessed after incubation with honey varieties for 24 h.
  
  
  RESULTS
  Arid region honey exhibited superior erythrocyte membrane protection effect with H4 measuring 1.3 ± 0.042mMTE/g and H2 measuring 1.122 ± 0.018mMTE/g. MDA levels were significantly reduced by honey samples, especially H4 (20.819 ± 0.63 nmol/mg protein). We observed a significant decrease in cell population in PC-3 after 24 h in culture on treatment with honey. A moderate increase in NO levels was observed in both cultures after 24 h at the same time levels of IL-6 were remarkably reduced by honey varieties.
  
  
  CONCLUSIONS
  The results demonstrate the antioxidant effect of arid region honey due to its erythrocyte membrane protection effect and subsequent lowering of oxidative damage as evident from lower levels of lipid peroxidation byproduct MDA. Arid region honey varieties were as good as non-arid region types at decreasing cell viability of prostate cancer cells. The moderate increase in NO levels in PC-3 and PBMCs were not significant enough to elicit any pro-inflammatory response. However, IL-6 secretion was remarkably reduced by all honey varieties in a comparable level indicating the potential anti-inflammatory property of arid region honey.
authors.affiliation: Nutrition and Health Department, College of Food and Agriculture, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates.
authors.forename: Serene
authors.initials: S
authors.lastname: Hilary
authors.affiliation: Alexandria University, 22 El-Guish Road, El-Shatby, Alexandria, 21526, Egypt.
authors.forename: Hosam
authors.initials: H
authors.lastname: Habib
authors.affiliation: Nutrition and Health Department, College of Food and Agriculture, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates.
authors.forename: Usama
authors.initials: U
authors.lastname: Souka
authors.affiliation: Nutrition and Health Department, College of Food and Agriculture, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates.
authors.forename: Wissam
authors.initials: W
authors.lastname: Ibrahim
authors.affiliation: Nutrition and Health Department, College of Food and Agriculture, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates. platatcarine@uaeu.ac.ae.
authors.forename: Carine
authors.initials: C
authors.lastname: Platat
mesh_terms: D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D004910:Erythrocyte Membrane / Q000187:drug effects; D004912:Erythrocytes / Q000166:cytology / Q000378:metabolism; D035264:Flowers / Q000737:chemistry / Q000145:classification; D006461:Hemolysis; D006722:Honey / Q000032:analysis*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D015850:Interleukin-6; D009569:Nitric Oxide; D008315:Malondialdehyde
keywords: Anti-inflammation; Anti-tumor; Antioxidant; Arid region; Hemolysis; Honey; MDA