scholarly journals Inhibition of Acute Phase Inflammation byLaminaria japonicathrough Regulation of iNOS-NF-κB Pathway

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Seong Kyu Park ◽  
Sook Jahr Park ◽  
Sang Mi Park ◽  
Il Je Cho ◽  
Chan Ik Park ◽  
...  

Laminaria japonicahas been frequently used as food supplements in many of the Asian countries and as a drug in traditional oriental medicine. This research investigated the effects ofLaminaria japonicaextract (LJE) on acute phase inflammation in a carrageenan-induced paw edema model, as assessed by histomorphometric and immunohistochemical analyses. The effect of LJE was also evaluated in Raw264.7 cells stimulated with lipopolysaccharide (LPS) in the aspect of the inhibition of nitric oxide (NO), prostaglandin E2(PGE2), and proinflammatory cytokines production. NO, PGE2, tumor necrosis factor (TNF)-α, interleukin-1β, and interleukin-6 contents were assayed by ELISA, and inducible NO synthase (iNOS) and cyclooxygenase (COX)-2 expressions were determined by western blot analyses. In rats, LJE treatment inhibited carrageenan-induced paw edema formation and infiltration of inflammatory cells in H&E staining. LJE treatment prevented the ability of LPS to increase the levels of iNOS and COX-2 protein in a concentration-dependent manner. Consistently, LJE suppressed the production of TNF-α, interleukin-1β, and interleukin-6. Treatment of the cells with LJE caused inhibition of inhibitor ofκBαphosphorylation induced by LPS, suggesting LJE repression of nuclear factor-κB activity by LPS. In conclusion, this study shown here may be of help to understand the action mechanism of LJE and the anti-inflammatory use ofL. japonica.

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Kook Ho Sohn ◽  
Mi Jeong Jo ◽  
Won Joon Cho ◽  
Jong Rok Lee ◽  
Il Je Cho ◽  
...  

Bojesodok-eum(BSE) is a herbal prescription consisting ofCoptidis RhizomaandScutellariae Radixas main components. This paper investigated the effects of BSE on the induction of nitric oxide (NO), prostaglandin E2(PGE2), and proinflammatory cytokines that are caused by lipopolysaccharide (LPS) in murine macrophage cell line and on the paw edema formation in animals. Administration of BSE (0.3 g/kg and 1 g/kg) in rats significantly inhibited carrageenan-induced paw edema formation, as did dexamethasone, an anti-inflammatory positive control drug. In cell model, treatment of BSE decreased the production of NO and PGE2in RAW264.7 cells stimulated by LPS. BSE also inhibited the expression of iNOS and COX-2 protein as well as COX activity in a concentration-dependent manner. Consistently, BSE suppressed the ability of LPS to produce TNF-α, interleukin-1β, and interleukin-6. LPS treatment induced nuclear NF-κB level and I-κBαphosphorylation, which were inhibited subsequent treatment of BSE, suggesting its repression of LPS-inducible NF-κB activation. BSE abrogated the induction of NO, PGE2, and proinflammatory cytokines, as well as iNOS and COX-2 protein expression in RAW264.7 cells stimulated by LPS as mediated with NF-κB inhibition.


1992 ◽  
Vol 284 (3) ◽  
pp. 645-648 ◽  
Author(s):  
M K Ganapathi

Okadaic acid (OA), a specific inhibitor of protein phosphatases 1 and 2A, inhibited in a dose-dependent manner (5-20 nM) the induction of C-reactive protein (CRP), serum amyloid A (SAA) and fibrinogen by interleukin-6 (IL-6) plus interleukin-1 (IL-1), and of fibrinogen by IL-6 alone, in Hep 3B cells. Induction of alpha 1-proteinase inhibitor (alpha 1-PI) by IL-6 plus IL-1 or IL-6 alone was not significantly affected by OA up to concentrations of 20 nM, above which concentration OA was toxic in Hep 3B cells. OA also inhibited the induction of CRP, fibrinogen and alpha 1-PI by IL-6 in the NPLC/PRF/5 cell line, albeit at a higher concentration (80 nM). These results suggest that the signal transduction mechanisms regulating induction of acute-phase proteins by IL-6, either alone or in combination with IL-1, are mediated by activation of protein phosphatases 1 and/or 2A.


2007 ◽  
Vol 282 (38) ◽  
pp. 27622-27632 ◽  
Author(s):  
Byeong-Churl Jang ◽  
Su-Haeng Sung ◽  
Jong-Gu Park ◽  
Jong-Wook Park ◽  
Jae Hoon Bae ◽  
...  

COX-2 and its products, including prostaglandin E2, are involved in many inflammatory processes. Glucosamine (GS) is an amino monosaccharide and has been widely used for alternative regimen of (osteo) arthritis. However, the mechanism of action of GS on COX-2 expression remains unclear. Here we describe a new action mechanism of glucosamine hydrochloride (GS-HCl) to tackle endogenous and agonistdriven COX-2 at protein level. GS-HCl (but not GS sulfate, N-acetyl GS, or galactosamine HCl) resulted in a shift in the molecular mass of COX-2 from 72–74 to 66–70 kDa and concomitant inhibition of prostaglandin E2 production in a concentration-dependent manner in interleukin (IL)-1β-treated A549 human lung epithelial cells. Remarkably, GS-HCl-mediated decrease in COX-2 molecular mass was associated with inhibition of COX-2 N-glycosylation during translation, as assessed by the effect of tunicamycin, the protein N-glycosylation inhibitor, or of cycloheximide, the translation inhibitor, on COX-2 modification. Specifically, the effect of low concentration of GS-HCl (1 mm) or of tunicamycin (0.1 μg/ml) to produce the aglycosylated COX-2 was rescued by the proteasomal inhibitor MG132 but not by the lysosomal or caspase inhibitors. However, the proteasomal inhibitors did not show an effect at 5 mm GS-HCl, which produced the aglycosylated or completely deglycosylated form of COX-2. Notably, GS-HCl (5 mm) also facilitated degradation of the higher molecular species of COX-2 in IL-1β-treated A549 cells that was retarded by MG132. GS-HCl (5 mm) was also able to decrease the molecular mass of endogenous and IL-1β- or tumor necrosis factor-α-driven COX-2 in different human cell lines, including Hep2 (bronchial) and H292 (laryngeal). However, GS-HCl did not affect COX-1 protein expression. These results demonstrate for the first time that GS-HCl inhibits COX-2 activity by preventing COX-2 co-translational N-glycosylation and by facilitating COX-2 protein turnover during translation in a proteasome-dependent manner.


2003 ◽  
Vol 228 (7) ◽  
pp. 786-794 ◽  
Author(s):  
Wieslaw Kozak ◽  
David M. Aronoff ◽  
Olivier Boutaud ◽  
Anna Kozak

Cytochrome P-450 monooxygenase (epoxygenase)-derived arachidonic acid (AA) metabolites, including 11,12-epoxyeicosatrienoic acid (11,12-EET), possess anti-inflammatory and antipyretic properties. Prostaglandin E2 (PGE2), a cyclooxygenase (COX)-derived metabolite of AA, is a well-defined mediator of fever and inflammation. We have tested the hypothesis that 11,12-EET attenuates synthesis of PGE2 in monocytes, which are the cells that are indispensable for induction of fever and initiation of inflammation. Monocytes isolated from freshly collected rat blood were stimulated with lipopolysaccharide (LPS; 100 ng/2 × 105 cells) to induce COX-2 and stimulate generation of PGE2. SKF-525A, an inhibitor of epoxygenases, significantly augmented the lipopolysaccharide-provoked synthesis of PGE2 in cell culture in a concentration-dependent manner. It did not affect, however, elevation of the expression of COX-2 protein in monocytes stimulated with LPS. 11,12-EET also did not affect the induction of COX-2 in monocytes incubated with lipopolysaccharide. However, 11,12-EET suppressed, in a concentration-dependent fashion, the generation of PGE2 in incubates. Preincubation of a murine COX-2 preparation for 0–5 min with three concentrations of 11,12-EET (1, 5, and 10 μM) inhibited the oxygenation of [14C]-labeled AA by the enzyme. The inhibitory effect of 11,12-EET on COX-2 was time-and-concentration-dependent, suggesting a mechanism-based inhibition. Based on these data, we conclude that 11,12-EET suppresses generation of PGE2 in monocytes via modulating the activity of COX-2. These data support the hypothesis that epoxygenasederived AA metabolites constitute a negative feedback on the enhanced synthesis of prostaglandins upon inflammation.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Ji Choul Ryu ◽  
Sang Mi Park ◽  
Min Hwangbo ◽  
Sung Hui Byun ◽  
Sae Kwang Ku ◽  
...  

Artemisia apiaceaHance is one of the most widely used herbs for the treatment of malaria, jaundice, and dyspeptic complaint in oriental medicine. This study investigated the effects of methanol extracts ofA. apiaceaHance (MEAH) on the induction of inducible nitric oxide synthase (iNOS) and proinflammatory mediators by lipopolysaccharide (LPS) in Raw264.7 macrophage cells and also evaluated thein vivoeffect of MEAH on carrageenan-induced paw edema in rats. MEAH treatment in Raw264.7 cells significantly decreased LPS-inducible nitric oxide production and the expression of iNOS in a concentration-dependent manner, while MEAH (up to 100 μg/mL) had no cytotoxic activity. Results from immunoblot analyses and ELISA revealed that MEAH significantly inhibited the expression of cyclooxygenase-2, tumor necrosis factor-α, interleukin-1β, and interleukin-6 in LPS-activated cells. As a plausible molecular mechanism, increased degradation and phosphorylation of inhibitory-κBαand nuclear factor-κB accumulation in the nucleus by LPS were partly blocked by MEAH treatment. Finally, MEAH treatment decreased the carrageenan-induced formation of paw edema and infiltration of inflammatory cells in rats. These results demonstrate that MEAH has an anti-inflammatory therapeutic potential that may result from the inhibition of nuclear factor-κB activation, subsequently decreasing the expression of proinflammatory mediators.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Megumi Kobayashi ◽  
Kenta Watanabe ◽  
Satoshi Yokoyama ◽  
Chiho Matsumoto ◽  
Michiko Hirata ◽  
...  

Capsaicin, a transient receptor potential vanilloid type 1 (TRPV1) ligand, regulates nerve-related pain-sensitive signals, inflammation, and cancer growth. Capsaicin suppresses interleukin-1-induced osteoclast differentiation, but its roles in bone tissues and bone diseases are not known. This study examined the effects of capsaicin on inflammatory bone resorption and prostaglandin E (PGE) production induced by lipopolysaccharide (LPS) in vitro and on bone mass in LPS-treated mice in vivo. Capsaicin suppressed osteoclast formation, bone resorption, and PGE production induced by LPS in vitro. Capsaicin suppressed the expression of cyclooxygenase-2 (COX-2) and membrane-bound PGE synthase-1 (mPGES-1) mRNAs and PGE production induced by LPS in osteoblasts. Capsaicin may suppress PGE production by inhibiting the expression of COX-2 and mPGES-1 in osteoblasts and LPS-induced bone resorption by TRPV1 signals because osteoblasts express TRPV1. LPS treatment markedly induced bone loss in the femur in mice, and capsaicin significantly restored the inflammatory bone loss induced by LPS in mice. TRPV1 ligands like capsaicin may therefore be potentially useful as clinical drugs targeting bone diseases associated with inflammatory bone resorption.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Hai Yang Yu ◽  
Kyoung-Sook Kim ◽  
Young-Choon Lee ◽  
Hyung-In Moon ◽  
Jai-Heon Lee

Oleifolioside A, a new triterpenoid compound isolated fromDendropanax morbiferaLeveille (D. morbifera), was shown in this study to have potent inhibitory effects on lipopolysaccharide (LPS-)stimulated nitric oxide (NO) and prostaglandin E2(PGE2) production in RAW 264.7 macrophages. Consistent with these findings, oleifolioside A was further shown to suppress the expression of LPS-stimulated inducible nitric oxide synthase (iNOS) and cyclooxigenase-2 (COX-2) in a dose-dependent manner at both the protein and mRNA levels and to significantly inhibit the DNA-binding activity and transcriptional activity of NF-κB in response to LPS. These results were found to be associated with the inhibition of the degradation and phosphorylation of IκB-αand subsequent translocation of the NF-κB p65 subunit to the nucleus. Inhibition of NF-κB activation by oleifolioside A was also shown to be mediated through the prevention of p38 MAPK and ERK1/2 phosphorylation. Taken together, our results suggest that oleifolioside A has the potential to be a novel anti-inflammatory agent capable of targeting both the NF-κB and MAPK signaling pathways.


Stroke ◽  
2021 ◽  
Vol 52 (Suppl_1) ◽  
Author(s):  
Abraham Al-Ahmad ◽  
Vardan T Karamyan

Increased brain microvascular permeability and disruption of blood-brain barrier (BBB) function are among hallmarks of ischemic stroke. Recently, peptidase neurlysin (Nln) has been identified as a compensatory and cerebroprotective mechanism in the post-stroke brain that functions to process a diverse group of extracellular neuropeptides, including bradykinin (BK), neurotensin (NT) and substance P (SP). A number of studies suggest involvement of BK, NT and SP in BBB impairment and edema formation after stroke, however there is paucity of data in regards to the direct effects of these peptides on the brain microvascular endothelial cells (BMECs) and BBB. The purpose of this study was to evaluate the direct effects of BK, NT and SP on permeability of BBB in an in vitro model based on human, induced pluripotent stem cell (iPSC)-derived BMECs. Our data indicate that all three peptides increase BBB permeability in a concentration-dependent manner in an in vitro model formed from two different iPSC lines (CTR90F and CTR65M) and widely used hCMEC/D3 human BMECs. Combination of BK, NT and SP at a sub-effective concentration also resulted in increased BBB permeability in the iPSC-derived model. Furthermore, we observed abrogation of BK, NT and SP effects with pretreatment of pharmacological blockers targeting their specific receptors or in presence of recombinant neurolysin (Nln). This is the first experimental study to document increased permeability of BBB in response to direct action of NT in an in vitro model. In addition, our study confirms the expected but not well-documented, direct effect of SP on BBB permeability and adds to the well-recognized actions of BK on BBB. Lastly, we demonstrate that peptidase Nln can neutralize the effects of these peptides on BBB, suggesting potential therapeutic implications.


2020 ◽  
Vol 48 (10) ◽  
pp. 030006052096399
Author(s):  
Guixiang Liao ◽  
Zhihong Zhao ◽  
Hongli Yang ◽  
Xiaming Li

Objective Sirtuin 3 (SIRT3) plays a vital role in regulating oxidative stress in tissue injury. The aim of this study was to evaluate the radioprotective effects of honokiol (HKL) in a zebrafish model of radiation-induced brain injury and in HT22 cells. Methods The levels of reactive oxygen species (ROS), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) were evaluated in the zebrafish brain and HT22 cells. The expression levels of SIRT3 and cyclooxygenase-2 (COX-2) were measured using western blot assays and real-time polymerase chain reaction (RT-PCR). Results HKL treatment attenuated the levels of ROS, TNF-α, and IL-1β in both the in vivo and in vitro models of irradiation injury. Furthermore, HKL treatment increased the expression of SIRT3 and decreased the expression of COX-2. The radioprotective effects of HKL were achieved via SIRT3 activation. Conclusions HKL attenuated oxidative stress and pro-inflammatory responses in a SIRT3-dependent manner in radiation-induced brain injury.


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