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.

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.

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.

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 .

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.

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.

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.

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.

Silymarin Inhibits Morphological Changes in LPS-Stimulated Macrophages by Blocking NF-kappaB Pathway

The present study showed that silymarin, a polyphenolic flavonoid isolated from milk thistle (Silybum marianum), inhibited lipopolysaccharide (LPS)-induced morphological changes in the mouse RAW264.7 macrophage cell line. We also showed that silymarin inhibited the nuclear translocation and transactivation activities of nuclear factor-kappa B (NF-kappaB), which is important for macrophage activation-associated changes in cell morphology and gene expression of inflammatory cytokines. BAY-11-7085, an NF-kappaB inhibitor, abrogated LPS-induced morphological changes and NO production, similar to silymarin. Treatment of RAW264.7 cells with silymarin also inhibited LPS-stimulated activation of mitogen-activated protein kinases (MAPKs). Collectively, these experiments demonstrated that silymarin inhibited LPS-induced morphological changes in the RAW264.7 mouse macrophage cell line. Our findings indicated that the most likely mechanism underlying this biological effect involved inhibition of the MAPK pathway and NF-kappaB activity. Inhibition of these activities by silymarin is a potentially useful strategy for the treatment of inflammation because of the critical roles played by MAPK and NF-kappaB in mediating inflammatory responses in macrophages.

Fisetin Suppresses Macrophage-Mediated Inflammatory Responses by Blockade of Src and Syk

Flavonoids, such as fisetin (3,7,3',4'-tetrahydroxyflavone), are plant secondary metabolites. It has been reported that fisetin is able to perform numerous pharmacological roles including anti-inflammatory, anti-microbial, and anti-cancer activities; however, the exact anti-inflammatory mechanism of fisetin is not understood. In this study, the pharmacological action modes of fisetin in lipopolysaccharide (LPS)-stimulated macrophage-like cells were elucidated by using immunoblotting analysis, kinase assays, and an overexpression strategy. Fisetin diminished the release of nitric oxide (NO) and reduced the mRNA levels of inducible NO synthase (iNOS), tumor necrosis factor (TNF)-alpha, and cyclooxygenase (COX)-2 in LPS-stimulated RAW264.7 cells without displaying cytotoxicity. This compound also blocked the nuclear translocation of p65/nuclear factor (NF)-kappaB. In agreement, the upstream phosphorylation events for NF-kappaB activation, composed of Src, Syk, and IkappaBalpha, were also reduced by fisetin. The phospho-Src level, triggered by overexpression of wild-type Src, was also inhibited by fisetin. Therefore, these results strongly suggest that fisetin can be considered a bioactive immunomodulatory compound with anti-inflammatory properties through suppression of Src and Syk activities.

Acetylshikonin Inhibits Human Pancreatic PANC-1 Cancer Cell Proliferation by Suppressing the NF-kappaB Activity

Acetylshikonin, a natural naphthoquinone derivative compound, has been used for treatment of inflammation and cancer. In the present study, we have investigated whether acetylshikonin could regulate the NF-kappaB signaling pathway, thereby leading to suppression of tumorigenesis. We observed that acetylshikonin significantly reduced proliferation of several cancer cell lines, including human pancreatic PANC-1 cancer cells. In addition, acetylshikonin inhibited phorbol 12-myristate 13-acetate (PMA) or tumor necrosis-alpha (TNF-alpha)-induced NF-kappaB reporter activity. Proteome cytokine array and real-time RT-PCR results illustrated that acetylshikonin inhibition of PMA-induced production of cytokines was mediated at the transcriptional level and it was associated with suppression of NF-kappaB activity and matrix metalloprotenases. Finally, we observed that an exposure of acetylshikonin significantly inhibited the anchorage-independent growth of PANC-1 cells. Together, our results indicate that acetylshikonin could serve as a promising therapeutic agent for future treatment of pancreatic cancer.

Diallyl Disulfide Prevents Cyclophosphamide-Induced Hemorrhagic Cystitis in Rats through the Inhibition of Oxidative Damage, MAPKs, and NF-kappaB Pathways

This study investigated the possible effects and molecular mechanisms of diallyl disulfide (DADS) against cyclophosphamide (CP)-induced hemorrhagic cystitis (HC) in rats. Inflammation response was assessed by histopathology and serum cytokines levels. We determined the protein expressions of nuclear transcription factor kappa-B (NF-kappaB), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and tumor necrosis factor-alpha (TNF-alpha), oxidative stress, urinary nitrite-nitrate, malondialdehyde (MDA), and 8-hydroxy-2'-deoxyguanosine (8-OHdG). Finally, we studied the involvement of mitogen-activated protein kinases (MAPKs) signaling in the protective effects of DADS against CP-induced HC. CP treatment caused a HC which was evidenced by an increase in histopathological changes, proinflammatory cytokines levels, urinary nitrite-nitrate level, and the protein expression of NF-kappaB, COX-2, iNOS, TNF-alpha, p-c-Jun N-terminal kinase (JNK), and p-extracellular signal regulated kinase (ERK). The significant decreases in glutathione content and glutathione-S-transferase and glutathione reductase activities, and the significant increase in MDA content and urinary MDA and 8-OHdG levels indicated that CP-induced bladder injury was mediated through oxidative DNA damage. In contrast, DADS pretreatment attenuated CP-induced HC, including histopathological lesion, serum cytokines levels, oxidative damage, and urinary oxidative DNA damage. DADS also caused significantly decreased the protein expressions of NF-kappaB, COX-2, iNOS, TNF-alpha, p-JNK, and p-ERK. These results indicate that DADS prevents CP-induced HC and that the protective effects of DADS may be due to its ability to regulate proinflammatory cytokines production by inhibition of NF-kappaB and MAPKs expressions, and its potent anti-oxidative capability through reduction of oxidative DNA damage in the bladder.

Scutellarein Reduces Inflammatory Responses by Inhibiting Src Kinase Activity

Flavonoids are plant pigments that have been demonstrated to exert various pharmacological effects including anti-cancer, anti-diabetic, anti-atherosclerotic, anti-bacterial, and anti-inflammatory activities. However, the molecular mechanisms in terms of exact target proteins of flavonoids are not fully elucidated yet. In this study, we aimed to evaluate the anti-inflammatory mechanism of scutellarein (SCT), a flavonoid isolated from Erigeron breviscapus, Clerodendrum phlomidis and Oroxylum indicum Vent that have been traditionally used to treat various inflammatory diseases in China and Brazil. For this purpose, a nitric oxide (NO) assay, polymerase chain reaction (PCR), nuclear fractionation, immunoblot analysis, a kinase assay, and an overexpression strategy were employed. Scutellarein significantly inhibited NO production in a dose-dependent manner and reduced the mRNA expression levels of inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-alpha in lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, SCT also dampened nuclear factor (NF)-kappaB-driven expression of a luciferase reporter gene upon transfection of a TIR-domain-containing adapter-inducing interferon-beta (TRIF) construct into Human embryonic kidney 293 (HEK 293) cells; similarly, NF-kappa B nuclear translocation was inhibited by SCT. Moreover, the phosphorylation levels of various upstream signaling enzymes involved in NF-kappaB activation were decreased by SCT treatment in LPS-treated RAW264.7 cells. Finally, SCT strongly inhibited Src kinase activity and also inhibited the autophosphorylation of overexpressed Src. Therefore, our data suggest that SCT can block the inflammatory response by directly inhibiting Src kinase activity linked to NF-kappaB activation.

Study on the mechanism of homocysteine-induced microglia expression of interleukin-1β and tumor necrosis factor-α / 中华老年医学杂志

Objective To investigate the mechanism of homocysteine-induced microglia (BV-2 cells) expression of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α).Methods The BV-2 cells were divided into blank control group,cysteine (Cys) group,homocysteine (Hcy) group and homocysteine and glutathione (Hcy+GSH) group,and the BV-2 cells in these groups were incubated with cysteine or homocysteine or homocysteine and glutathione together for 72 h.The mRNA expressions of IL-1β and TNF-α were assessed by RT-qPCR.The protein expressions of IL-1β and TNF-α in supernatant were detected by enzyme linked immunosorbent assay (ELISA).Western blot was used to observe the changes of NF-κB/p65 expression.Results There were significant differences in mRNA and protein expressions of IL-1β and TNF-α and NF-κB/p65 protein expression between groups (F=48.63,130.76,702.91,293.69,212.06,respectively,all P=0.000).The secretions of IL-1β and TNF-α were significantly improved by homocysteine (P＜0.05),and were reversed by the treatment with glutathione (P＜0.05).Western blot assay result showed that NF-κB/p65 was elevated after treatment with homocysteine (P＜0.05).Conclusions Homocysteine can induce microglia expression of interleukin-1β and tumor necrosis factor-α,and NF-κB signaling pathway may be involved in this process.