interleukin-8 and acetovanillone

Inflammation is an important therapeutic target. Due to their potency, steroidal drugs dominate the current treatment of inflammatory disorders. However, steroidal drugs can also exert a broad range of side effects and appear not always effective. This calls for the development of alternative drugs with a different mechanism of action, which are likely to be found in the field of natural products (NPs). For many NPs strong anti-inflammatory effects have been described, but usually investigating a single compound in a single assay. In this study, eight promising NPs were selected and tested against the strong anti-inflammatory drug prednisolone. For this head-to-head comparison, in vitro assays were used which represent different pathways of the inflammatory response: TNF-α and IL-6 expression by macrophages, IL-8 expression by colon epithelial cells, ROS production in polymorphonuclear leukocytes and platelet activation in whole blood. Performance profiles were established which allowed us to identify curcumin, berberine chloride and epigallocatechin gallate as potential alternatives for prednisolone or other glucocorticoids in inflammation.

Topics: Acetophenones; Animals; Anti-Inflammatory Agents; Berberine; Biological Products; Blood Platelets; Caco-2 Cells; Catechin; Cell Line; Curcumin; Humans; Interleukin-6; Interleukin-8; Macrophages; Mice; Neutrophils; Platelet Activation; Pravastatin; Prednisolone; Primary Cell Culture; Reactive Oxygen Species; Stilbenes; Tumor Necrosis Factor-alpha

We aimed to investigate the preventive and therapeutic effect of apocynin (APO) on bleomycin (BLC)-induced lung injury in rats. Rats were assigned into groups as follows: control group; APO group, 20 mg/kg APO was given intraperitoneal for 29 days; BLC-1 and BLC-2 groups, a single intratracheal injection of BLC (2.5 mg/kg); APO+BLC-preventive group, 20 mg/kg APO was administered 12 h before the intratracheal BLC injection and continued for 14 days; BLC+APO-treatment group, 20 mg/kg APO was given on the 14th day after the intratracheal BLC injection and continued to sacrifice. The BLC-1 group was sacrificed on the 14th day of BLC administration to validate BLC-induced lung inflammation and fibrosis on the 14th of study initiation. All other groups were sacrificed on the 29th day after BLC administration. The semiquantitative histopathological assessment, tissue levels of malondialdehyde (MDA), superoxide dismutase, catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), total antioxidant capacity, total oxidant status (TOS), and oxidative stress index (OSI) were measured. An addition to the serum myeloperoxidase (MPO), the cell count and cytokines (IL-1β, IL-6, and IL-8) of bronchoalveolar lavage (BAL) fluid were assayed. BLC-provoked histological changes were significantly detected compared to the control group. APO restored these histological damages in different quantity in the treatment and prevention groups. BLC caused a significant decrease in GSH, CAT, and GPX, which were accompanied with significantly the increased MDA, TOS levels, and OSI in the lung tissue concomitant with increased levels of the cellular account and proinflammatory cytokines in the BAL fluid. Otherwise, APO administration, both before and after BLC, reversed all biochemical markers and cytokine as well as histopathological changes induced by BLC. Interestingly, APO treatment reversed MPO activity in serum increased by BLC. In this study, both protective and therapeutic effects of APO against BLC-induced lung fibrosis were demonstrated for the first time.

Topics: Acetophenones; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antioxidants; Biomarkers; Bleomycin; Bronchoalveolar Lavage Fluid; Catalase; Disease Models, Animal; Female; Glutathione; Glutathione Peroxidase; Interleukin-1beta; Interleukin-6; Interleukin-8; Lung; Lung Injury; Malondialdehyde; Oxidative Stress; Peroxidase; Pulmonary Fibrosis; Rats; Rats, Wistar; Superoxide Dismutase

The mechanism underlying the inflammatory role of TRPA1 in lung epithelial cells (LECs) remains unclear. Here, we show that cigarette smoke extract (CSE) sequentially induced several events in LECs. The Ca(2+) influx was prevented by decreasing extracellular reactive oxygen species (ROS) with the scavenger N-acetyl-cysteine, removing extracellular Ca(2+) with the chelator EGTA, or treating with the TRPA1 antagonist HC030031. NADPH oxidase activation was abolished by its inhibitor apocynin, EGTA, or HC030031. The increased intracellular ROS was halted by apocynin, N-acetyl-cysteine, or HC030031. The activation of the MAPKs/NF-κB signaling was suppressed by EGTA, N-acetyl-cysteine, or HC030031. IL-8 induction was inhibited by HC030031 or TRPA1 siRNA. Additionally, chronic cigarette smoke (CS) exposure in wild-type mice induced TRPA1 expression in LECs and lung tissues. In CS-exposure trpa1 (-/-) mice, the increased BALF level of ROS was similar to that of CS-exposure wild-type mice; yet lung inflammation was lessened. Thus, in LECs, CSE may initially increase extracellular ROS, which activate TRPA1 leading to an increase in Ca(2+) influx. The increased intracellular Ca(2+) contributes to activation of NADPH oxidase, resulting in increased intracellular ROS, which activate the MAPKs/NF-κB signaling leading to IL-8 induction. This mechanism may possibly be at work in mice chronically exposed to CS.

Topics: Acetanilides; Acetophenones; Animals; Biomarkers; Bronchoalveolar Lavage Fluid; Calcium; Calcium Channels; Chelating Agents; Chemokine CXCL2; Egtazic Acid; Enzyme Activation; Gene Expression Regulation, Neoplastic; Humans; Inflammation; Interleukin-8; Lung; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mice, Transgenic; NADPH Oxidases; Nerve Tissue Proteins; Oxidative Stress; Purines; Reactive Oxygen Species; RNA, Small Interfering; Smoke; Transient Receptor Potential Channels; TRPA1 Cation Channel

Major diseases such as cardiovascular diseases, rheumatoid arthritis, diabetes, obesity and tumor growth are known to involve inflammation. Inflammatory molecules such as MCP-1, TNF-α, IL-1β and IL-8 are known to promote angiogenesis. MCP-induced protein (MCPIP), originally discovered as a novel zinc finger protein induced by MCP-1, is also induced by other inflammatory agents. MCPIP was shown to mediate MCP-1-induced angiogenesis. Whether angiogenesis induced by other inflammatory agents is mediated via MCPIP is unknown and the molecular mechanisms involved in angiogenesis induced by MCPIP have not been elucidated. The aim of this study was to bridge this gap and delineate the sequential processes involved in angiogenesis mediated via MCPIP. siRNA knockdown of MCPIP was used to determine whether different inflammatory agents, MCP-1, TNF-α, IL-1β and IL-8, mediate angiogenesis via MCPIP in human umbilical vein endothelial cells (HUVECs). Chemical inhibitors and specific gene knockdown approach were used to inhibit each process postulated. Oxidative stress was inhibited by apocynin or cerium oxide nanoparticles or knockdown of NADPH oxidase subunit, phox47. Endoplasmic reticulum (ER) stress was blocked by tauroursodeoxycholate or knockdown of ER stress signaling protein IRE-1 and autophagy was inhibited by the use of 3'methyl adenine, or LY 294002 or by specific knockdown of beclin1. Matrigel assay was used as a tool to study angiogenic differentiation induced by inflammatory agents or MCPIP overexpression in HUVECs. Tube formation induced by inflammatory agents, TNF-α, IL-1β, IL-8 and MCP-1 was inhibited by knockdown of MCPIP. Forced MCPIP-expression induced oxidative stress, ER stress, autophagy and angiogenic differentiation in HUVECs. Inhibition of each step caused inhibition of each subsequent step postulated. The results reveal that angiogenesis induced by inflammatory agents is mediated via induction of MCPIP that causes oxidative and nitrosative stress resulting in ER stress leading to autophagy required for angiogenesis. The sequence of events suggested to be involved in inflammatory angiogenesis by MCPIP could serve as possible targets for therapeutic intervention of angiogenesis-related disorders.

Topics: Acetophenones; Anti-Inflammatory Agents, Non-Steroidal; Antiviral Agents; Apoptosis Regulatory Proteins; Autophagy; Beclin-1; Chemokine CCL2; Chromones; Endoplasmic Reticulum Stress; Endoribonucleases; Human Umbilical Vein Endothelial Cells; Humans; Interleukin-1beta; Interleukin-8; Membrane Proteins; Morpholines; Neovascularization, Physiologic; Oxidative Stress; Protein Serine-Threonine Kinases; Reactive Oxygen Species; Ribonucleases; RNA Interference; RNA, Small Interfering; Taurochenodeoxycholic Acid; Transcription Factors; Tumor Necrosis Factor-alpha

Chronic inflammation incited by bacteria in the saccular lung of premature infants contributes to the pathogenesis of bronchopulmonary dysplasia (BPD). LPS-mediated type II alveolar epithelial cell (AEC) injury induces the expression of pro-inflammatory cytokines that trigger pulmonary neutrophil influx, alveolar matrix degradation and lung remodeling. We hypothesized that NADPH oxidase (Nox)-dependent mechanisms mediate LPS-induced cytokine expression in AEC. We examined the role of p47phox in mediating LPS-dependent inflammatory cytokine expression in A549 cells (which exhibit phenotypic features characteristic of type II AEC) and elucidated the proximal signaling events by which Nox is activated by LPS. LPS-induced ICAM-1 and IL-8 expression was associated with increased superoxide formation in AEC. LPS-mediated oxidative stress and cytokine expression was inhibited by apocynin and augmented by PMA demonstrating that Nox-dependent redox signaling regulates LPS-dependent pro-inflammatory signaling in AEC. In LPS-treated cells, p47phox translocated from the cytoplasm to the perinuclear region and co-localized with gp91phox. LPS also induced a temporal increase in p47phox serine304 phosphorylation in AEC. While inhibition of classical PKC and novel PKC with calphostin and rottlerin did not inhibit ICAM-1 or IL-8 expression, the myristolyated PKCζ pseudosubstrate peptide (a specific inhibitor of PKCζ) inhibited LPS-induced cytokine expression in AEC. Inhibition of PKCζ also attenuated LPS-mediated p47phox phosphorylation and perinuclear translocation in AEC. Consistent with these data, LPS activated PKCζ in AEC as evidenced by increased threonine410 phophorylation. We conclude that PKCζ-mediated p47phox activation regulates LPS-dependent cytokine expression in AEC. Selective inhibition of PKCζ or p47phox might attenuate LPS-mediated inflammation and alveolar remodeling in BPD.

Topics: Acetophenones; Benzopyrans; Cell Line, Tumor; Enzyme Inhibitors; Enzyme-Linked Immunosorbent Assay; Humans; Immunoblotting; Intercellular Adhesion Molecule-1; Interleukin-8; Lipopolysaccharides; NADPH Oxidases; Naphthalenes; Oxidative Stress; Protein Kinase C; Pulmonary Alveoli; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Signal Transduction; Superoxides; Tetradecanoylphorbol Acetate

Cigarette smoke (CS) increases chemokine production in lung epithelial cells (LECs), but the pathways involved are not completely understood. AMP-activated protein kinase (AMPK), a crucial regulator of energy homeostasis, may modulate inflammation. Here, we show that cigarette smoke extract sequentially activated NADPH oxidase; increased intracellular reactive oxygen species (ROS) level; activated AMPK, NF-κB, and STAT3; and induced interleukin 8 (IL-8) in human LECs. Inhibition of NADPH oxidase activation by apocynin or siRNA targeting p47(phox) (a subunit of NADPH oxidase) attenuated the increased intracellular ROS level, AMPK activation, and IL-8 induction. Removal of intracellular ROS by N-acetylcysteine reduced the AMPK activation and IL-8 induction. Prevention of AMPK activation by Compound C or AMPK siRNA lessened the activation of both NF-κB and STAT3 and the induction of IL-8. Abrogation of the activation of NF-κB and STAT3 by BAY11-7085 and AG490, respectively, attenuated the IL-8 induction. We additionally show that chronic CS exposure in mice promoted AMPK phosphorylation and expression of MIP-2α (an IL-8 homolog) in LECs and lungs, as well as lung inflammation, all of which were reduced by Compound C treatment. Thus, a novel NADPH oxidase-dependent, ROS-sensitive AMPK signaling is important for CS-induced IL-8 production in LECs and possibly lung inflammation.

Topics: Acetophenones; AMP-Activated Protein Kinases; Animals; Cell Line; Humans; Interleukin-8; Male; Mice; Mice, Inbred C57BL; Models, Animal; NADPH Oxidases; Plant Extracts; Pneumonia; Pyrazoles; Pyrimidines; Respiratory Mucosa; RNA, Small Interfering; Signal Transduction; Smoking