Avenanthramides, polyphenols from oats, exhibit anti-inflammatory and anti-itch activity.
Oatmeal has been used for centuries as a soothing agent to relieve itch and irritation associated with various xerotic dermatoses; however few studies have sought to identify the active phytochemical(s) in oat that mediate this anti-inflammatory activity. Avenanthramides are phenolic compounds present in oats at approximately 300 parts per million (ppm) and have been reported to exhibit anti-oxidant activity in various cell-types. In the current study we investigated whether these compounds exert anti-inflammatory activity in the skin. We found that avenanthramides at concentrations as low as 1 parts per billion inhibited the degradation of inhibitor of nuclear factor kappa B-alpha (IkappaB-alpha) in keratinocytes which correlated with decreased phosphorylation of p65 subunit of nuclear factor kappa B (NF-kappaB). Furthermore, cells treated with avenanthramides showed a significant inhibition of tumor necrosis factor-alpha (TNF-alpha) induced NF-kappaB luciferase activity and subsequent reduction of interleukin-8 (IL-8) release. Additionally, topical application of 1-3 ppm avenanthramides mitigated inflammation in murine models of contact hypersensitivity and neurogenic inflammation and reduced pruritogen-induced scratching in a murine itch model. Taken together these results demonstrate that avenanthramides are potent anti-inflammatory agents that appear to mediate the anti-irritant effects of oats.
Sur
Runa
R
Preclinical Pharmacology, Skin Research Center, Johnson & Johnson Consumer Products, 199 Grandview Road, Skillman, NJ 08558, USA.
Nigam
Anu
A
Grote
Devon
D
Liebel
Frank
F
Southall
Michael D
MD
D000818:Animals; D018554:Avena; D002478:Cells, Cultured; D003877:Dermatitis, Contact / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism; D004195:Disease Models, Animal; D004224:Diterpenes / Q000009:adverse effects; D005419:Flavonoids / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D007249:Inflammation / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D016209:Interleukin-8 / Q000378:metabolism; D015603:Keratinocytes / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D016328:NF-kappa B / Q000378:metabolism; D010081:Oxazolone / Q000009:adverse effects; D010636:Phenols / Q000494:pharmacology / Q000627:therapeutic use*; D008517:Phytotherapy; D059808:Polyphenols; D011537:Pruritus / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology; D062367:ortho-Aminobenzoates / Q000494:pharmacology / Q000627:therapeutic use*
D004224:Diterpenes; D005419:Flavonoids; D016209:Interleukin-8; D016328:NF-kappa B; D010636:Phenols; D059808:Polyphenols; D062367:ortho-Aminobenzoates; D010081:Oxazolone; C514463:avenanthramide-2C; C024353:resiniferatoxin