Cell-free chromatin: A newly described mediator of systemic inflammation

Recent research has shown that cell-free chromatin (cfCh) particles that are released from the billions of cells that die in thebody everyday can enter into healthy cells, integrate into their genomes and induce dsDNA breaks and apoptotic responses.Genomic integration of cfCh activates NFjB suggesting a novel mechanism of induction of systemic inflammation. SinceDNA damage and inflammation are underlying pathologies in multiple devastating acute and chronic disease conditions,the discovery of agents that can inactivate cfCh may provide therapeutic possibilities.

TLR4/NF-kappaB p65 signaling pathway mediates protective effect of triptolide on endothelium in rats with endotoxemia / 中国中药杂志

The aim of this paper was to observe the effect of triptolide( TP) on cardiovascular function and its possible mechanism by intraperitoneal injection of bacterial lipopolysaccharide in rats with endotoxemia. Sixty male Sprague-Dawley rats were randomly divided intonormal group( NC group),endotoxemia model group( LPS group),TP low concentration intervention group( LPS + TP-L group,25 μg·kg~(-1)),TP middle concentration intervention group( LPS+TP-M group,50 μg·kg~(-1)),TP high concentration intervention group( LPS+TP-H group,100 μg·kg~(-1)) and polymyxin B group( LPS+PMX-B group,0. 2 mg·kg~(-1)). 10 mg·kg~(-1) LPS was injected intraperitoneally for 6 h to replicate the endotoxemia rat model. The rats in TP intervention groups were pre-treated 15 min before intraperitoneal injection of LPS. Rats in each group underwent total arterial intubation to measure hemodynamic parameters: heart rate( HR),left ventricular diastolic pressure( LVDP),the maximum rate of the increase/decrease of left ventricular pressure( ±dp/dtmax). The levels of BNP,CK-MB and c Tn-Ⅰ in serum and levels of TNF-α and IL-6 in plasma were detected by ELISA. The contents of p65 protein in myocardium and contents of p65,TLR4,i NOS and e NOS protein in thoracic aorta were detected by Western blot. As compared with NC group,the hemodynamic indexes in LPS group were significantly decreased; the contents of BNP,CK-MB and c Tn-Ⅰ in serum,TNF-α and IL-6 in plasma,p65 in myocardium,i NOS,e NOS,TLR4 and p65 in vascular tissues were significantly increased. As compared with LPS group,the hemodynamic indexes were significantly improved in LPS+TP-M group,LPS+TP-H group and LPS+PMX-B group; the contents of BNP,CK-MB and c Tn-Ⅰ in serum,TNF-α and IL-6 in plasma,p65 in myocardium,i NOS,e NOS,TLR4 and p65 in vascular tissues were significantly decreased in each treatment group. Triptolide has a protective effect on cardiovascular damage in a dose-dependent manner in endotoxemia rats,probably through TLR4/NF-κB p65 signaling pathway to improve endothelial function.

Effect of sevoflurane preconditioning on HMGB1∕TLR4∕NF-κB signaling pathway during lung ische-mia-reperfusion in rats / 中华麻醉学杂志

Objective To evaluate the effect of sevoflurane preconditioning on high-mobility group box 1 protein ( HMGB1) ∕Toll-like receptor 4 ( TLR4) ∕nuclear factor kappa B ( NF-κB) signaling pathway during lung ischemia-reperfusion ( I∕R) in rats. Methods Thirty-six clean-grade healthy male Sprague-Dawley rats, aged 8-10 weeks, weighing 200-250 g, were divided into 3 groups ( n=12 each) using a random number table method: sham operation group ( group S) , lung I∕R group ( group I∕R) and sevoflu-rane preconditioning group ( group SP ) . The right pulmonary hilum was only isolated but not ligated in group S. Lung I∕R was induced by clamping the right pulmonary hilum for 60 min followed by 120 min of reperfusion in anesthetized rats in group I∕R. In group SP, 2. 1％ sevoflurane was inhaled for 30 min to per-form sevoflurane preconditioning, and the lung I∕R model was established at 10 min after the end of inhala-tion. The rats were sacrificed at 120 min of reperfusion, and the lungs were removed for examination of the pathological changes which were scored and for determination of wet to dry weight ratio ( W∕D ratio) , con-tent of tumor necrosis factor-alpha ( TNF-α) in lung tissues ( by enzyme-linked immunosorbent assay) and expression of HMGB1, TLR4 and NF-κB protein in lung tissues (by Western blot). Results Compared with group S, the pathological scores, W∕D ratio and content of TNF-α were significantly increased, and the expression of HMGB1, TLR4 and NF-κB was up-regulated in I∕R and SP groups ( P<0. 05) . Compared with group I∕R, the pathological scores, W∕D ratio and content of TNF-αwere significantly decreased, and the expression of HMGB1, TLR4 and NF-κB was down-regulated ( P<0. 05) , and the pathological changes of lung tissues were significantly attenuated in group SP . Conclusion Sevoflurane preconditioning reduces lung I∕R injury probably through inhibiting HMGB1∕TLR4∕NF-κB signaling pathway in rats.

The expression of nuclear factor κB signal molecule in Kashin-Beck disease and its role in chondrocyte apoptosis / 中华地方病学杂志

Objective To clarify the role of nuclear factor κB(NF-κB) signaling pathway in pathogenesis of Kashin-Beck disease(KBD) by observing the expression of NF-κB p65 in the whole blood samples of patients with KBD and controls,and the expression of NF-κB p65 in C28/I2 chondrocyte, and to analyze the role of NF-κB p65 molecule in chondrocyte apoptosis. Methods Through a case-control study, 161 patients with KBD (KBD group) were selected from Xunyi, Yongshou, Changwu, Linyou, Qianyang and Long counties in KBD endemic areas and 312 healthy people(control group) were matched by age and sex in Shaanxi Province. Venous blood samples were collected from patients and healthy controls, which were anticoagulated and used for determination of NF-κB p65 protein.According to the group design,the model of C28/I2 chondrocyte oxidative damage was established.The experiments were divided into 4 groups including control group(C), tBHP injury group (O, tBHP 300.00 μmol/L), low selenium pre-protection group (OS1, 0.05 mg/L Na2SeO3+ 300.00 μmol/L tBHP), and middle selenium pre-protection group(OS2, 0.10 mg/L Na2SeO3+ 300.00 μmol/L tBHP). Then, cell apoptosis was detected by Hoechst 33342 and reactive oxygen species (ROS) was detected by dichlorfluorescein(DCF) method. The protein was extracted by Trizol method, then protein expression level of NF-κB p65 molecule was detected by Western blotting in whole blood samples and C28/I2 chondrocyte. Results The differences in age and sex were not statistically significant between KBD group and control group (t = 0.336, P > 0.05; χ2= 0.407, P > 0.05). The protein expression level of NF-κB p65 in KBD group was 1.835 times as high as that of control group (KBD:0.167 ± 0.026, control: 0.091 ± 0.014, t = 5.147, P < 0.01). Under the fluorescence microscope, chondrocyte showed strong blue fluorescence in tBHP group and the level of ROS(1.219 ± 0.104) was higher than those of low and middle selenium pre-protection groups(0.832 ± 0.077, 0.635 ± 0.070, P < 0.05).The protein expression level of NF-κB p65 in tBHP group (1.563 ± 0.351) was higher than that of control group (0.451 ± 0.069, P < 0.05), and protein levels of NF-κB p65 had a decreasing tendency in low and middle selenium pre-protection groups compared to tBHP group. Conclusion The NF-κB signaling pathway is up-regulated in KBD patients, moreover, chondrocyte experiments show that cell apoptosis is mediated via upregulation of NF-κB p65,which suggests NF-κB signaling pathway may play an important role in pathogenesis of KBD.

Effects of inhibiting peritoneal macrophage caspase recruitment domain-containing protein 9 on inflammatory reaction of severe acute pancreatitis in rats / 中华消化杂志

Objective To investigate the effects of caspase recruitment domain-containing protein 9 (CARD9)expression in peritoneal macrophages on severe acute pancreatitis(SAP)in rats and its mechanism.Methods A total of 60 male Sprague Dawley rats were divided into control group(n=6), SAP group(n=18),small interfering RNA(siRNA)control group(n=18)and siRNA CARD9 group (n=18).SAP rat models were established.At three,six and twelve hours after the models were established,ascites was collected,peritoneum was lavaged and peritoneal macrophages were isolated and cultured.The expressions of CARD9,nuclear factor-kappaB(NF-κB),p38 mitogen-activated protein kinase(p38MA PK)at mRNA level in peritoneal macrophages was measured by real-time polymerase chain reaction(RT-PCR).The levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-1β and IL-6 in peripheral blood were detected by enzyme-linked immunosorbent assay(ELISA).LSD or Tamhane′s T2 methods were performed for statistical analysis.Results At three,six and twelve hours after the models were established,CA RD9 mRNA levels of peritoneal macrophages in SAP group were 1.63 ± 0.05,1.68 ± 0.24 and 2.61 ± 0.02,respectively,which were all higher than that of control group(1.01 ± 0.23),and the differences were statistically significant(t=25.97,6.86 and 131.59;all P<0.05);the levels of CA RD9 mRNA of siRNA CARD9 group were 1.45 ± 0.02,1.24 ± 0.03 and 1.63 ± 0.03,respectively,which were lower than that of SAP group at the same time points,and the differences were statistically significant(t=-7.81,-4.46 and -62.13;all P< 0.05).At three,six and twelve hours after the models were established,the mRNA levels of NF-κB and p38MA PK of peritoneal macrophages of rats in SAP group were 1.51 ± 0.08,1.81 ± 0.10,2.30 ± 0.05 and 1.37 ± 0.13,1.69 ± 0.18,2.42 ± 0.23,respectively, which were higher than those of control group(1.00 ± 0.01,1.03 ± 0.08),and the differences were statistically significant(tNF-κB=15.10,19.95 and 60.36;tp38MAPK=5.37,8.34 and 14.11;all P<0.05);the levels of N F-κB mRNA in siRNA CARD9 group were 1.38 ± 0.05,1.57 ± 0.06 and 1.76 ± 0.09, respectively,which were lower than that of SAP group at the same time points,and the differences were statistically significant(t= -3.32,-5.07 and -12.70;all P<0.05).At six and twelve hours after the models were established,the p38MA PK mRNA levels of siRNA CARD9 group were 1.50 ± 0.10 and 2.00 ± 0.09,respectively,which were lower than that of SAP group,and the differences were statistically significantly(t= -2.30 and -4.17,both P< 0.05).At three,six and twelve hours after the models were established,the levels of TNF-α,IL-1β and IL-6 in peripheral blood of SAP group were(53.49 ± 21.64)pg/mL,(108.62 ± 22.76)pg/mL and(139.00 ± 15.35)pg/mL;(43.86 ± 18.30)pg/mL, (87.51 ± 17.10)pg/mL and(117.27 ± 14.57)pg/mL;(78.38 ± 32.70)pg/mL,(156.39 ± 30.56)pg/mL and(209.56 ± 26.09)pg/mL,respectively,which were higher than those of control group((2.79 ± 1.17),(7.13 ± 4.52),(12.73 ± 8.08)pg/mL),and the differences were statistically significant(tTNF-α=5.73,11.37 and 21.69;tIL-1β=4.77,11.13 and 17.68;tIL-6=4.77,11.32 and 17.68;all P<0.05).At six and twelve hours after the models were established,the levels of TNF-α,IL-1β and IL-6 of siRNA CARD9 group were(75.73 ± 16.93)pg/mL,(108.23 ± 14.02)pg/mL;(63.05 ± 11.98)pg/mL, (91.56 ± 14.28)pg/mL and(112.67 ± 21.40)pg/mL,(163.62 ± 25.51)pg/mL,respectively,which were lower than those of SAP group,and the differences were statistically significant(tTNF-α= -2.84,-3.63;tIL-1β= -2.88,-3.09;tIL-6= -2.88,-3.09;all P< 0.05).Conclusions There are CARD9-related NF-κB and p38MAPK pathways in peritoneal macrophages of SAP rats.Intervention of the expression of CARD9 in peritoneal macrophages,especially at early stage of SAP may relieve the inflammation reaction and pancreatic injury,which may provide a new method for SAP treatment.

Effect of mAb2G4-ODN-lip on myocardial ischemia-reperfusion injury in rats / 中华麻醉学杂志

Objective To evaluate the effect of anti-myosin monoclonal antibodies-nuclear factor kappa B (NF-κB) decoy oligodeoxynucleotides-lipofectamine compound (mAb2G4-ODN-lip) on myocardial ischemia-reperfusion (I/R) injury in rats.Methods Forty clean-grade healthy adult male Sprague-Dawley rats,aged 8-10 weeks,weighing 240-260 g,were divided into 4 groups (n=10 each) using a random number table:sham operation group (group S),myocardial I/R group (group I/R),ODN-lip group (group ODN) and mAb2G4-ODN-lip group (group mAb2G4).Myocardial I/R was induced by occlusion of the left anterior descending branch of coronary artery for 30 min followed by 120 min reperfusion.In ODN and mAb2G4 groups,ODN-lip (100 μg ODN) and mAb2G4-ODN-lip (100 μg ODN) compounds were injected via the femoral vein,respectively,immediately after onset of ischemia.The left anterior descending branch of coronary artery was only occluded but not ligated in group S.The animals were sacrificed at 120 min of reperfusion and myocardial specimens of the left ventricle on the ischemic side were obtained for examination of the pathological changes (using haematoxylin and eosin staining) and for determination of the expression of NF-κB (by Western blot) and contents of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) (by enzyme-linked immunosorbent assay).Results Compared with group S,the expression of NF-κB was significantly up-regulated,and the contents of TNF-α and IL-6 were increased in I/R,ODN and mAb2G4 groups (P＜ 0.05).Compared with group I/R,the expression of NF-κB was significantly down-regulated,and the contents of TNF-α and IL-6 were decreased in ODN and mAb2G4 groups (P＜0.05).Compared with group ODN,the expression of NF-κB was significantly down-regulated,and the contents of TNF-α and IL-6 were decreased in group mAb2G4 (P＜0.05).The pathological changes of myocardial tissues were significantly attenuated in group I/R,group ODN and group mAb2G4 in turn.Conclusion mAb2G4-ODN-lip can mitigate myocardial I/R injury in rats.

The role and its significance of the receptor activator of nuclear factor-κB ligand in arterial calcification / 中华老年医学杂志

Objective To investigate the mechanism that receptor activator of NF-κB ligand (RANKL) promotes arterial calcification.Methods Firstly,RANKL was added into the culture media,in which the monocyte precursor cells alone were cultured.Morphological observation and tartrate resistant acid phosphatase(TRAP)stain were used to assess whether RANKL could induce the monocyte precursor cells to differentiate into osteoclast-like cells.During arterial calcification,both in vivo and in vitro expressions of RANKL and osteoprotegerin (OPG,as RANKL inhibitor)were measured via real-time PCR.The extent of osteoclast-like cell differentiation was also assessed.Results It was found that RANKL could induce osteoclast-like cell differentiation.There were no both in vivo and in vitro expressions of osteoclast-like cells in the early stage of calcification.At that time,the ratio of RANKL to OPG was very low.In the late stage of calcification,a small amount of osteoclast-like cell expression coincided with a relatively high ratio of RANKL to OPG.According to the results,the ratio of RANKL to OPG was very low during most of the arterial calcification period.This made it possible for OPG to completely inhibit RANKL-induced osteoclast-like cell differentiation.The ratio of RANKL to OPG was (0.36 ± 0.08) (F =36) and (1.68 ± 0.08) (F =36) respectively in the early and late subgroup of calcification group in the animal model,but was zero in the control group(both P＜0.05).The ratio of RANKL to OPG was(0.42±0.09) (F=16)and(1.50 ± 0.10)(F=16)respectively in the early and late subgroup of calcification group in the cell model,but was zero in the control group(both P＜0.05).Conclusions Our result likely explains why RANKL has the ability to induce osteoclast-like cell differentiation,but acts as a promoter of calcification.

The recent advances in the research of NF-κB in the development and relevant treatment of the colorec-tal cancer / 实用肿瘤学杂志

In eukaryotic cells ,NF-κB transcription factor family regulates many processes like cell sur-vival,growth,and apoptosis.It participates in the development of a variety of diseases ,including inflammatory,im-mune disease ,and cancer .As an inflammatory factor , NF-κB mediates the transformation of chronic colitis to cancer during the course of colorectal cancer .Furthermore,it could inhibit cell apoptosis through regulating cell cycles,which promotes the development of colorectal cancer and mediates the multidrug resistance of the tumor cells.Therefore,targeting NF-κB,a large number of preparations involved both Chinese and western medicine has been researched .The further research and the use of them may be an effective method to cure the colorectal cancer in clinical work .

Deficiency of Lipocalin-2 Promotes Proliferation and Differentiation of Osteoclast Precursors via Regulation of c-Fms Expression and Nuclear Factor-kappa B Activation

BACKGROUND: Lipocalin-2 (LCN2), a small glycoprotein, has a pivotal role in diverse biological processes such as cellular proliferation and differentiation. We previously reported that LCN2 is implicated in osteoclast formation induced by receptor activator of nuclear factor-kappa B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF). In the present study, we used a knockout mouse model to further investigate the role of LCN2 in osteoclast development. METHODS: Osteoclastogenesis was assessed using primary bone marrow-derived macrophages. RANKL and M-CSF signaling was determined by immunoblotting, cell proliferation by bromodeoxyuridine (BrdU) enzyme-linked immunosorbent assay (ELISA), and apoptosis by cell death detection ELISA. Bone morphometric parameters were determined using a micro-computed tomography system. RESULTS: Our results showed that LCN2 deficiency increases tartrate-resistant acid phosphatase (TRAP)-positive multinucleated osteoclast formation in vitro, a finding that reflects enhanced proliferation and differentiation of osteoclast lineage cells. LCN2 deficiency promotes M-CSF-induced proliferation of bone marrow macrophages (BMMs), osteoclast precursors, without altering their survival. The accelerated proliferation of LCN2-deficient precursors is associated with enhanced expression and activation of the M-CSF receptor, c-Fms. Furthermore, LCN2 deficiency stimulates the induction of c-Fos and nuclear factor of activated T cells c1 (NFATc1), key transcription factors for osteoclastogenesis, and promotes RANKL-induced inhibitor of kappa B (IkappaBalpha) phosphorylation. Interestingly, LCN2 deficiency does not affect basal osteoclast formation in vivo, suggesting that LCN2 might play a role in the enhanced osteoclast development that occurs under some pathological conditions. CONCLUSIONS: Our study establishes LCN2 as a negative modulator of osteoclast formation, results that are in accordance with our previous findings.

alpha-Lipoic Acid Inhibits Expression of IL-8 by Suppressing Activation of MAPK, Jak/Stat, and NF-kappaB in H. pylori-Infected Gastric Epithelial AGS Cells

The epithelial cytokine response, associated with reactive oxygen species (ROS), is important in Helicobacter pylori (H. pylori)-induced inflammation. H. pylori induces the production of ROS, which may be involved in the activation of mitogen-activated protein kinases (MAPK), janus kinase/signal transducers and activators of transcription (Jak/Stat), and oxidant-sensitive transcription factor, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kappaB), and thus, expression of interleukin-8 (IL-8) in gastric epithelial cells. alpha-lipoic acid, a naturally occurring thiol compound, is a potential antioxidant. It shows beneficial effects in treatment of oxidant-associated diseases including diabetes. The present study is purposed to investigate whether alpha-lipoic acid inhibits expression of inflammatory cytokine IL-8 by suppressing activation of MAPK, Jak/Stat, and NF-kappaB in H. pylori-infected gastric epithelial cells. Gastric epithelial AGS cells were pretreated with or without alpha-lipoic acid for 2 h and infected with H. pylori in a Korean isolate (HP99) at a ratio of 300:1. IL-8 mRNA expression was analyzed by RT-PCR analysis. IL-8 levels in the medium were determined by enzyme-linked immunosorbent assay. NF-kappaB-DNA binding activity was determined by electrophoretic mobility shift assay. Phospho-specific and total forms of MAPK and Jak/Stat were assessed by Western blot analysis. ROS levels were determined using dichlorofluorescein fluorescence. As a result, H. pylori induced increases in ROS levels, mRNA, and protein levels of IL-8, as well as the activation of MAPK [extracellular signal-regulated kinase 1/2 (ERK1/2), c-Jun NH2-terminal kinase 1/2 (JNK1/2), p38], Jak/Stat (Jak1/2, Stat3), and NF-kappaB in AGS cells, which was inhibited by alpha-lipoic acid. In conclusion, alpha-lipoic acid may be beneficial for prevention and/or treatment of H. pylori infection-associated gastric inflammation.

Epigallocatechin-3-gallate rescues LPS-impaired adult hippocampal neurogenesis through suppressing the TLR4-NF-kappaB signaling pathway in mice

Adult hippocampal dentate granule neurons are generated from neural stem cells (NSCs) in the mammalian brain, and the fate specification of adult NSCs is precisely controlled by the local niches and environment, such as the subventricular zone (SVZ), dentate gyrus (DG), and Toll-like receptors (TLRs). Epigallocatechin-3-gallate (EGCG) is the main polyphenolic flavonoid in green tea that has neuroprotective activities, but there is no clear understanding of the role of EGCG in adult neurogenesis in the DG after neuroinflammation. Here, we investigate the effect and the mechanism of EGCG on adult neurogenesis impaired by lipopolysaccharides (LPS). LPS-induced neuroinflammation inhibited adult neurogenesis by suppressing the proliferation and differentiation of neural stem cells in the DG, which was indicated by the decreased number of Bromodeoxyuridine (BrdU)-, Doublecortin (DCX)- and Neuronal Nuclei (NeuN)-positive cells. In addition, microglia were recruited with activatingTLR4-NF-kappaB signaling in the adult hippocampus by LPS injection. Treating LPS-injured mice with EGCG restored the proliferation and differentiation of NSCs in the DG, which were decreased by LPS, and EGCG treatment also ameliorated the apoptosis of NSCs. Moreover, pro-inflammatory cytokine production induced by LPS was attenuated by EGCG treatment through modulating the TLR4-NF-kappaB pathway. These results illustrate that EGCG has a beneficial effect on impaired adult neurogenesis caused by LPSinduced neuroinflammation, and it may be applicable as a therapeutic agent against neurodegenerative disorders caused by inflammation.

(E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone displays suppression of inflammatory responses via inhibition of Src, Syk, and NF-kappaB

(E)-3-(3-methoxyphenyl)-1-(2-pyrrolyl)-2-propenone (MPP) is an aldol condensation product resulting from pyrrole-2-carbaldehyde and m- and p- substituted acetophenones. However, its biological activity has not yet been evaluated. Since it has been reported that some propenone-type compounds display anti-inflammatory activity, we investigated whether MPP could negatively modulate inflammatory responses. To do this, we employed lipopolysaccharide (LPS)-stimulated macrophage-like RAW264.7 cells and examined the inhibitory levels of nitric oxide (NO) production and transcriptional activation, as well as the target proteins involved in the inflammatory signaling cascade. Interestingly, MPP was found to reduce the production of NO in LPS-treated RAW264.7 cells, without causing cytotoxicity. Moreover, this compound suppressed the mRNA levels of inflammatory genes, such as inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-alpha. Using luciferase reporter gene assays performed in HEK293 cells and immunoblotting analysis with nuclear protein fractions, we determined that MPP reduced the transcriptional activation of nuclear factor (NF)-kappaB. Furthermore, the activation of a series of upstream signals for NF-kappaB activation, composed of Src, Syk, Akt, and IkappaBalpha, were also blocked by this compound. It was confirmed that MPP was able to suppress autophosphorylation of overexpressed Src and Syk in HEK293 cells. Therefore, these results suggest that MPP can function as an anti-inflammatory drug with NF-kappaB inhibitory properties via the suppression of Src and Syk.

Lobaric Acid Inhibits VCAM-1 Expression in TNF-alpha-Stimulated Vascular Smooth Muscle Cells via Modulation of NF-kappaB and MAPK Signaling Pathways

Lichens have been known to possess multiple biological activities, including anti-proliferative and anti-inflammatory activities. Vascular cell adhesion molecule-1 (VCAM-1) may play a role in the development of atherosclerosis. Hence, VCAM-1 is a possible therapeutic target in the treatment of the inflammatory disease. However, the effect of lobaric acid on VCAM-1 has not yet been investigated and characterized. For this study, we examined the effect of lobaric acid on the inhibition of VCAM-1 in tumor necrosis factor-alpha (TNF-alpha)-stimulated mouse vascular smooth muscle cells. Western blot and ELISA showed that the increased expression of VCAM-1 by TNF-alpha was significantly suppressed by the pre-treatment of lobaric acid (0.1-10 mug/ml) for 2 h. Lobaric acid abrogated TNF-alpha-induced NF-kappaB activity through preventing the degradation of IkappaB and phosphorylation of extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK), and p38 mitogen activated protein (MAP) kinase. Lobaric acid also inhibited the expression of TNF-alpha receptor 1 (TNF-R1). Overall, our results suggest that lobaric acid inhibited VCAM-1 expression through the inhibition of p38, ERK, JNK and NF-kappaB signaling pathways, and downregulation of TNF-R1 expression. Therefore, it is implicated that lobaric acid may suppress inflammation by altering the physiology of the atherosclerotic lesion.

The Anti-Inflammatory Effect of Arginine-Vasopressin on Lipopolysaccharide-Induced IkappaBalpha/Nuclear Factor-kappaB Cascade / 대한구급학회지

BACKGROUND: Arginine vasopressin (AVP) is widely used as a vasopressor agent. Some recent studies have suggested that AVP may exert an immunomodulatory effect. However, the mechanism about the anti-inflammatory effect of AVP is not well known. We investigated the effect of AVP on the ihibitor of kappa B (IkappaBalpha)/nuclear factor-kappa B (NF-kappaB) pathway in RAW 264.7 cells. METHODS: Cultured RAW 264.7 cells were pretreated with AVP and stimulated with lipopolysaccharide (LPS). To evaluate the effect of AVP on inflammatory cytokines, the concentration of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were assessed by an enzyme-linked immunosorbent assay technique. The expression of IkappaBalpha and nuclear translocation of NF-kappaB p65 were measured by Western blotting, and IkappaB kinase (IKK) activity was analyzed by an in vitro immune complex kinase assay. To confirm the AVP effect on IkappaBalpha/NF-kappaB cascade and via V2 receptor, we added tolvaptan (V2 receptor antagonist) after AVP pretreatment. RESULTS: The increase of IL-6 and TNF-alpha in LPS-stimulated RAW 264.7 cells was suppressed by a treatment with AVP. Pretreatment of AVP inhibited increasing of IKK activity and IkappaBalpha degradation induced by LPS in RAW 264.7 cells. Furthermore, LPS induced and NF-kappaB transcription was inhibited by AVP pretreatment. The observed changes in IKK activity, IkappaBalpha degradation and NF-kappaB transcription by AVP was abolished by tolvaptan treatment. CONCLUSIONS: Our results suggest that AVP showed anti-inflammatory effect on LPS-induced IkappaBalpha/NF-kappaB cascade in mouse macrophages via V2 receptors.

Growth Differentiation Factor 15 Expression in Astrocytes After Excitotoxic Lesion in the Mouse Hippocampus

Growth differentiation factor 15 (GDF15) is, a member of the transforming growth factor beta (TGF-beta) superfamily of proteins. Although GDF15 is well established as a potent neurotrophic factor for neurons, little is known about its role in glial cells under neuropathological conditions. We monitored GDF15 expression in astrocyte activation after a kainic acid (KA)-induced neurodegeneration in the ICR mice hippocampus. In control, GDF15 immunoreactivity (IR) was evident in the neuronal layer of the hippocampus; however, GDF15 expression had increased in activated astrocytes throughout the hippocampal region at day 3 after the treatment with KA. LPS treatment in astrocytes dramatically increased GDF15 expression in primary astrocytes. In addition, LPS treatment resulted in the decrease of the IkappaB-alpha degradation and increase of the phosphorylation level of RelA/p65. These results indicate that GDF15 has a potential link to NF-kappaB activation, making GDF15 a valuable target for modulating inflammatory conditions.

Curcumin utilizes the anti-inflammatory response pathway to protect the intestine against bacterial invasion

BACKGROUND/OBJECTIVES: Curcumin, a major component of the Curcuma species, contains antioxidant and anti-inflammatory properties. Although it was found to induce apoptosis in cancer cells, the functional role of curcumin as well as its molecular mechanism in anti-inflammatory response, particularly in intestinal cells, has been less investigated. The intestine epithelial barrier is the first barrier and the most important location for the substrate coming from the lumen of the gut. SUBJECTS/METHODS: We administered curcumin treatment in the human intestinal epithelial cell lines, T84 and Caco-2. We examined endoplasmic reticulum (ER) stress response by thapsigargin, qPCR of XBP1 and BiP, electrophysiology by wild-type cholera toxin in the cells. RESULTS: In this study, we showed that curcumin treatment reduces ER stress and thereby decreases inflammatory response in human intestinal epithelial cells. In addition, curcumin confers protection without damaging the membrane tight junction or actin skeleton change in intestine epithelial cells. Therefore, curcumin treatment protects the gut from bacterial invasion via reduction of ER stress and anti-inflammatory response in intestinal epithelial cells. CONCLUSIONS: Taken together, our data demonstrate the important role of curcumin in protecting the intestine by modulating ER stress and inflammatory response post intoxication.

Inhibitory Effect of Delphinidin on Extracellular Matrix Production via the MAPK/NF-kappaB Pathway in Nasal Polyp-Derived Fibroblasts

PURPOSE: Nasal polyps are associated with chronic inflammation of the mucous membranes in the nose and paranasal sinuses and involved in extracellular matrix (ECM) accumulation. Delphinidin promotes ECM degradation in hepatitis and cardiac fibrosis. The aims of this study were to examine the inhibitory effect of delphinidin on TGF-beta1-induced myofibroblast differentiation and ECM accumulation, and to determine the underlying mechanisms in nasal polyp-derived fibroblasts (NPDFs). METHODS: NPDFs were stimulated with TGF-beta1, with or without delphinidin, and the expression levels of alpha-SMA, fibronectin, and collagen type I were determined by RT-PCR, Western blot analysis, and collagen assay. The expression of alpha-SMA protein was measured by immunocytochemical staining. Mitogen-activated protein kinase and NF-kappaB activation induced by TGF-beta1 were determined by Western blot analysis. The transcriptional activity of NF-kappaB was measured by luciferase assay. RESULTS: The expression levels of alpha-SMA, fibronectin, and collagen type I increased in TGF-beta1-stimulated NPDFs. In TGF-beta1-induced NPDFs, delphinidin inhibited the expression of alpha-SMA, fibronectin, and collagen. Inhibitors of MAPK and NF-kappaB blocked the expression of alpha-SMA, fibronectin, and collagen type I. Delphinidin suppressed the activation of MAPK and NF-kappaB induced by TGF-beta1 stimulation. CONCLUSIONS: These results suggest that delphinidin may inhibit TGF-beta1-induced myofibroblast differentiation and ECM production through the MAPK/NF-kappaB signaling pathway in NPDFs.

Anti-Inflammatory Effects of Water Chestnut Extract on Cytokine Responses via Nuclear Factor-kappaB-signaling Pathway

Water chestnut (Trapa japonica Flerov.) is an annual aquatic plant. In the present study, we showed that the treatment of water chestnut extracted with boiling water resulted in a significant increase 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and decrease the intracellular H2O2-induced accumulation of reactive oxygen species. In addition, water chestnut extract (WCE) inhibited lipopolysaccharide (LPS)-induced nitric oxide production and suppressed mRNA and protein expression of the inducible nitric oxide synthase gene. The cytokine array results showed that WCE inhibited inflammatory cytokine secretion. Also, WCE reduced tumor necrosis factor-alpha- and interleukin-6-induced nuclear factor-kappaB activity. Furthermore, during sodium lauryl sulfate (SLS)-induced irritation of human skin, WCE reduced SLS-induced skin erythema and improved barrier regeneration. These results indicate that WCE may be a promising topical anti-inflammatory agent.

Differential Regulation of NF-kappaB Signaling during Human Cytomegalovirus Infection

NF-kappaB transcription factors are key regulators of immune and stress responses, apoptosis, and differentiation. Human cytomegalovirus (HCMV) activates or represses NF-kappaB signaling at different times during infection. An initial increase in NF-kappaB activity occurs within a few hours of infection. The virus appears to adapt to this change since initial viral gene expression is promoted by the elevated NF-kappaB activity. Because NF-kappaB upregulates innate immune responses and inflammation, it has also been suggested that HCMV needs to downregulate NF-kappaB signaling. Recent studies have shown that HCMV has various mechanisms that inhibit NF-kappaB signaling. HCMV reduces cell surface expression of tumor necrosis factor receptor 1 (TNFR1) and blocks the DNA binding activity of NF-kappaB. Furthermore, some HCMV tegument proteins antagonize NF-kappaB activation by targeting the key components of NF-kappaB signaling at late stages of infection. In this review, we summarize the recent findings on the relationship between HCMV and NF-kappaB signaling, focusing, in particular, on the viral mechanisms by which the NF-kappaB signaling pathway is inhibited.

The Anti-Inflammatory Effect of Arginine-Vasopressin on Lipopolysaccharide-Induced IkappaBalpha/Nuclear Factor-kappaB Cascade / 대한중환자의학회지

BACKGROUND: Arginine vasopressin (AVP) is widely used as a vasopressor agent. Some recent studies have suggested that AVP may exert an immunomodulatory effect. However, the mechanism about the anti-inflammatory effect of AVP is not well known. We investigated the effect of AVP on the ihibitor of kappa B (IkappaBalpha)/nuclear factor-kappa B (NF-kappaB) pathway in RAW 264.7 cells. METHODS: Cultured RAW 264.7 cells were pretreated with AVP and stimulated with lipopolysaccharide (LPS). To evaluate the effect of AVP on inflammatory cytokines, the concentration of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were assessed by an enzyme-linked immunosorbent assay technique. The expression of IkappaBalpha and nuclear translocation of NF-kappaB p65 were measured by Western blotting, and IkappaB kinase (IKK) activity was analyzed by an in vitro immune complex kinase assay. To confirm the AVP effect on IkappaBalpha/NF-kappaB cascade and via V2 receptor, we added tolvaptan (V2 receptor antagonist) after AVP pretreatment. RESULTS: The increase of IL-6 and TNF-alpha in LPS-stimulated RAW 264.7 cells was suppressed by a treatment with AVP. Pretreatment of AVP inhibited increasing of IKK activity and IkappaBalpha degradation induced by LPS in RAW 264.7 cells. Furthermore, LPS induced and NF-kappaB transcription was inhibited by AVP pretreatment. The observed changes in IKK activity, IkappaBalpha degradation and NF-kappaB transcription by AVP was abolished by tolvaptan treatment. CONCLUSIONS: Our results suggest that AVP showed anti-inflammatory effect on LPS-induced IkappaBalpha/NF-kappaB cascade in mouse macrophages via V2 receptors.