title: Hydroxytyrosol inhibits pro-inflammatory cytokines, iNOS, and COX-2 expression in human monocytic cells.
abstract: Hydroxytyrosol (HT), isolated from extra-virgin olive oil, possesses a marked antioxidant activity and is a good radical scavenger. In this study, our aim was to examine the anti-inflammatory mechanism of HT through measuring the inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) expression, TNF-alpha formation, and nitric oxide (NO) release in lipopolysaccharide (LPS)-induced human monocytic (THP-1) cells. Results showed that HT remarkably suppressed the LPS (1 microg/ml) induction of NO release. It also significantly attenuated the LPS-induced transcription of TNF-alpha, iNOS, and COX-2 in a dose-dependent manner. Furthermore, it was also found that HT in a concentration-dependent manner inhibited the expression of iNOS and COX-2 in THP-1 cells treated with 1 microg/ml LPS using Western Blot. Taken together, these results suggest that HT exerts anti-inflammatory effects probably through the suppression of COX-2 and iNOS expression.
authors.affiliation: Department of Laboratory Medicine, College of Medicine, Dalian University, Dalian, 116622, Liaoning, China.
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Zhang
authors.forename: Jun
authors.initials: J
authors.lastname: Cao
authors.forename: Laifu
authors.initials: L
authors.lastname: Zhong
mesh_terms: D051546:Cyclooxygenase 2 / Q000096:biosynthesis / Q000378:metabolism*; D016207:Cytokines / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D018836:Inflammation Mediators / Q000037:antagonists & inhibitors* / Q000502:physiology; D009000:Monocytes / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D052247:Nitric Oxide Synthase Type II / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives* / Q000494:pharmacology
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; C005975:3,4-dihydroxyphenylethanol; D052247:Nitric Oxide Synthase Type II; D051546:Cyclooxygenase 2; D010626:Phenylethyl Alcohol