Suppressive effect of carotenoid extract of Dunaliella salina alga on production of LPS-stimulated pro-inflammatory mediators in RAW264.7 cells via NF-κB and JNK inactivation

The carotenoid extract from Dunaliella salina was used to evaluate the suppressive effects on lipopolysaccharide (LPS)-induced pro-inflammatory mediators in RAW264.7 cells. The extract composed all-trans forms of alpha-carotene (28.8 mg/g extract), beta-carotene (471.1 mg/g extract), lutein (7.1 mg/g extract) and zeaxanthin (7.2 mg/g extract), 13- or 13'-cis-beta-carotene (12.1 mg/g extract), 9- or 9'-cis-alpha-carotene (19.1 mg/g extract) and 9- or 9'-cis-beta-carotene (440.3 mg/g extract) dose-dependently reduced the production of interleukin (IL)-1 beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha), the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and the secretion of nitric oxide (NO) and prostaglandin E-2 (PGE(2)) in LPS-activated RAW264.7 cells. Its attenuation of LPS-induced inflammatory responses was closely related to inhibition of the nuclear NF-kappa B p50 subunit translocation by blocking inhibitor of kappa B alpha (I kappa B) phosphorylation and degradation correlated with suppressing I kappa B kinase (IKK) alpha/beta phosphorylation, as well as down-regulation of the c-Jun NH2-terminal kinase (JNK) activation. (c) 2013 Elsevier Ltd. All rights reserved.