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Screening Bioactive Nanoparticles in Phagocytic Immune Cells for Inhibitors of Toll-like Receptor Signaling
Published on: July 26, 2017
Quercetin tetraacetyl derivative inhibits LPS-induced nitric oxide synthase (iNOS) expression in J774A.1 cells
M G Ortega1, A C Saragusti, J L Cabrera
1Farmacognosia, Departamento de Farmacia, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina.
Abstract:
In inflammation, nitric oxide (NO) acts as a pro-inflammatory mediator, which is synthesized by inducible nitric oxide synthase (iNOS) in response to pro-inflammatory agents such as lipopolysaccharide (LPS). Quercetin (Qt) has anti-inflammatory properties through its ability to inhibits nitric oxide production and iNOS expression in different cellular types. In the present study, we evaluated the effect of a semi-synthetic acetyl (quercetin-3,5,7,3'-tetraacetyl: TAQt) Qt derivative and two natural sulphated (quercetin-3-acetyl-7,3',4'-trisulphate: ATS and quercetin-3,7,3',4'-tetrasulphate: QTS) Qt derivatives on the LPS-induced NO production and iNOS expression in J774A.1 cells. Our results demonstrate that only TAQt inhibited the NO production by decreasing the iNOS mRNA and protein levels. In addition, we showed that TAQt blocked the LPS-induced nuclear NF-kappaB translocation by inhibiting the IkappaB-alpha degradation. Hence, as TAQt inhibited the LPS-induced iNOS expression and NO production, it could therefore be considered as a potential therapeutic agent for the treatment of inflammatory diseases related with the NO system.
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