Inhibition of LPS induced pro-inflammatory responses in RAW 264.7 macrophage cells by PVP-coated naringenin nanoparticle via down regulation of NF-κB/P38MAPK mediated stress signaling

Background: Naringenin (NAR) was found to display strong pharmacological properties. Since the clinical relevance of NAR is limited by its low bioavailability, we effectively synthesized and characterized a novel PVP-coated NAR nanoparticle (NAR NP) to enhance the therapeutic efficacy of NAR. The present study was designed to investigate the effects of NAR NP on lipopolysaccharide (LPS) induced inflammatory response in RAW 264.7 macrophage cells. Methods: In vitro cell culture studies of LPS stimulated RAW 264.7 macrophage cells were used as experimental model. Results: Cytotoxicity studies revealed that NAR NP is safe even at maximum tested concentration of 200 mg/ml. Initial dose fixation study in LPS induced RAW 264.7 cells, revealed the minimum optimal concentration required for anti inflammatory effect as 25 mg/ml. mRNA expression studies showed that NAR NP significantly down regulated the expressions of NF-kappa B and P38MAPK, which is paralleled with the inhibition of the nuclear translocation of NF-kappa B. This in turn led to the blockade of iNOS and COX-2, thereby inhibiting the production of nitric oxide and pro inflammatory cytokines such as TNF-alpha, IL-6, MCP-1 and IL-1 beta. NAR NP was found to be more efficient, when compared with NAR. Conclusions: Anti-inflammatory effects of NAR NP may be allocated to the down-regulation of COX -2 and iNOS via the suppression of NF-kappa B and MAPK signaling pathway in RAW 264.7 macrophages. The data suggests that NAR NP can be used as a potent candidate for the treatments of inflammatory diseases by exploiting the nanoscale properties and targeting efficacy. (c) 2017 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Sp. z o.o. All rights reserved.