interleukin-8 and protocatechuic-acid

Protocatechuic acid (PCA), a major metabolite of anthocyanins, has been shown to have antioxidant, antitumoral, and anti-inflammatory activities. In this study, we investigated the anti-inflammatory effects of PCA on lipopolysaccharide (LPS)-induced inflammatory response in human gingival fibroblasts (HGFs). The effects of PCA on LPS-induced inflammatory cytokines IL-6 and chemokines IL-8 in HGFs were detected by ELISA. The expression of NF-κB and PPAR-γ was detected by Western blot analysis. Our results demonstrated that PCA suppressed IL-6 and IL-8 production in LPS-stimulated HGFs. We also found that PCA inhibited LPS-induced NF-κB activation. Furthermore, the inhibition of PCA on LPS-induced IL-6 and IL-8 production can be reversed by PPAR-γ antagonist GW9662. In conclusion, the anti-inflammatory mechanism of PCA is associated with activating PPAR-γ, thereby inhibiting LPS-induced inflammatory response.

Topics: Anilides; Anti-Inflammatory Agents; Antioxidants; Cell Survival; Enzyme Activation; Gingiva; Humans; Hydroxybenzoates; Inflammation; Interleukin-6; Interleukin-8; Lipopolysaccharides; NF-kappa B; Periodontal Diseases; PPAR gamma

Polyphenols have been shown to exhibit anti-inflammatory, anti-oxidant and immunomodulatory activities. However, the effects of anthocyanins, flavonoids of great nutritional interest, in particular of their metabolite protocatechuic acid (PCA) on the phenotypic and functional maturation of human dendritic cells (DCs) are still largely unknown. In this study, we report that PCA is efficiently taken up and accumulated in human monocyte-derived DCs (MD-DCs). PCA exposure of MD-DCs markedly impaired the production of proinflammatory cytokines and chemokines (i.e. IL-6, IL-8 and CCL2) in response to bacterial endotoxin and leptin, and down-regulated the lipopolysaccharide (LPS)-induced migratory response of MD-DCs to CCL19. Conversely, the phenotypic profile induced by LPS-mediated activation as well as IL-12 production was not affected. Interestingly, we found that PPARγ is a main factor in the PCA-induced effects as blocking its activity abolish PCA capacity to down-regulate IL-6 and IL-8, but not CCL2, secretion and to inhibit MD-DC migration. In keeping with this observation, cytosol to nucleus translocation and PPARγ activity were found to be directly stimulated by PCA exposure of MD-DCs. These novel findings provide new insight into the immunoregulatory effects of polyphenol metabolites in DCs opening new perspectives on their potential application in the prevention of acute and chronic inflammatory diseases.

Topics: Anticarcinogenic Agents; Biological Transport; Cell Movement; Cells, Cultured; Chemokine CCL19; Chemokine CCL2; Dendritic Cells; Humans; Hydroxybenzoates; Interleukin-6; Interleukin-8; Leptin; Lipopolysaccharides; PPAR gamma

Cytotoxic effects of protocatechuic acid (PCA) upon 3 nonsmall cell lung cancer (NSCLC) cell lines, A549, H3255, and Calu-6 cell lines, were examined. PCA at 1, 2, 4, and 8 μM was used to treat these cells. Results showed that PCA dose-dependently reduced cell growth; and at 2-8 μM enhanced protein expression of Bax and cleaved caspase-3; as well as diminished Bcl-2 expression. This compound destabilized mitochondrial membrane via increasing caspase-3 activity, decreasing mitochondrial membrane potential and Na(+)-K(+)-ATPase activity in these cells. PCA treatments dose-dependently decreased protein expression of vascular endothelial growth factor and fibronectin, as well as lowered interleukin (IL)-6 and IL-8 release; and at 2-8 μM suppressed protein expression of basic fibroblast growth factor, matrix metalloproteinase (MMP)-2 and MMP-9. Furthermore, PCA treatments dose-dependently downregulated nuclear factor kappa (NF-κ)B p50 and NF-κB p65 protein expression, and at 2-8 μM suppressed protein expression of p-p38, p-JNK, and p-focal adhesion kinase (FAK). Our data revealed that PCA declined FAK, mitogen-activated protein kinase, and NF-κB activation, which subsequently decreased the production of cytokines and growth factors, and consequently inhibited proliferation of 3 test NSCLC cells. These findings suggest that PCA could provide wide-ranging anti-NSCLC potency.

Topics: Apoptosis; bcl-2-Associated X Protein; Carcinoma, Non-Small-Cell Lung; Caspase 3; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Down-Regulation; Fibronectins; Focal Adhesion Protein-Tyrosine Kinases; Humans; Hydroxybenzoates; Interleukin-6; Interleukin-8; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mitogen-Activated Protein Kinases; NF-kappa B; Signal Transduction; Vascular Endothelial Growth Factor A

Inflammation plays a crucial role in the pathophysiology of atherosclerosis. Besides cytokines, chemokines and cell adhesion molecules, CD40 and P-selectin play important roles as key regulators of the inflammatory process in atherosclerosis. Danshen (DS) is commonly used in traditional Chinese medicine for therapy of cardiovascular diseases such as coronary artery disease. The aim of the present study was to evaluate the protective effects of DS with respect to possible anti-inflammatory effects. Human umbilical vein endothelial cells as well as platelets were incubated with an extract of DS or one of its major ingredients salvianolic acid B (Sal B), tanshinone IIA (Tansh) and protocatechuic acid (Protoc) under tumor necrosis factor (TNF)-α or ADP stimulation. Expression of CD40 and cellular adhesion molecules (VCAM-1/ICAM-1) were assessed via flow cytometry. Levels of interleukin (IL)-6, IL-8, monocyte-chemoattractant-protein (MCP)-1 as well as soluble VCAM1 and ICAM-1 in the supernatants were examined via luminex based analysis. Treatment with DS attenuated TNF-α induced expression of CD40. Furthermore, the expression of VCAM-1 and ICAM-1 as well as the release of soluble VCAM-1 and ICAM-1 were downregulated. In the cell supernatants we also observed a significant reduction of IL-6, IL8 and MCP-1. DS and its major ingredients, Sal B and Protoc, significantly inhibited TNF-induced expression and release of adhesion molecules, cytokines and chemokines as well as ADP-induced expression of platelet P-selectin. Because of the key roles of inflammatory mediators in the etiology of atherosclerosis, this work provides useful insight in understanding the pharmacological efficacy of Chinese herbal medicine.

Topics: Abietanes; Adenosine Diphosphate; Anti-Inflammatory Agents; Atherosclerosis; Benzofurans; Blood Platelets; CD40 Antigens; Cells, Cultured; Chemokine CCL2; Down-Regulation; Drugs, Chinese Herbal; Human Umbilical Vein Endothelial Cells; Humans; Hydroxybenzoates; Inflammation Mediators; Intercellular Adhesion Molecule-1; Interleukin-6; Interleukin-8; P-Selectin; Salvia miltiorrhiza; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1