Exploring the anti-inflammatory activity of a novel 2-phenylquinazoline analog with protection against inflammatory injury

Inflammation is a protective immune response against harmful stimuli whose long time continuation results in host disease. Quinazolinones are nitrogen containing heterocyclic compounds with wide spectrum of biological activities. The anticancer effect of a 3-(arylideneamino)‐phenylquinazoline-4(3H)-one derivative was reported earlier. The anti-inflammatory effect of these quinazolinone derivatives has now been examined in endotoxin stimulated macrophages and in different in vivo models of inflammation by measuring the proinflammatory cytokines (TNF-α, IL-1β and IL-6), mediators NO and NF-κB (by ELISA and western blot), and translocation of the nuclear factor kB (by immunocytochemical analysis). To elucidate the in vivo effect, mice endotoxin model was and the various levels of edema, inflammatory pain and vascular permeability were studied. One of the quinazolinone derivatives showed significant anti-inflammatory activity in stimulated macrophage cells by inhibiting the expression of TNF-α, IL-1β, IL-6, iNOS, COX-2, p-IκB and NF-κBp65. Significant (P < 0.01) improvement was observed in the mortality of endotoxemic mice. The carrageenan and formalin-induced paw edema thicknesses were found to be reduced significantly (P < 0.01) along with the reduction of pain, vascular permeability and edema induced by complete Freund's adjuvant (P < 0.01). These findings indicate that 3-(arylideneamino)‐phenylquinazoline-4(3H)-one derivative as a potential anti-inflammatory agent.     

拮抗Toll样受体4对于溶血磷脂酸诱导的THP-1细胞Toll样受体4／核因子-κB信号通路的影响

目的：通过拮抗Toll样受体4（TLR4）观察其对于溶血磷脂酸（lysophosphatidic acid,LPA）诱导的人单核细胞株THP-1细胞的核因子-κB（nuclear factor-kappaB,NF-κB）p65表达的影响以及肿瘤坏死因子-α（TNF-α）水平的变化。方法取THP-1细胞,LPA以不同浓度水平（0～10μmol·L－1）刺激4 h,或1μmol·L－1浓度刺激不同时间（0～8 h）,酶联免疫吸附法（ELISA）测定细胞因子TNF-α,随后在LPA （1μmol·L－1）条件下分别予不同浓度TLR4单克隆抗体（TLR4 mAb）（5,20,30 mg·L－1）干预THP-1细胞,观察其对LPA诱导的核蛋白NF-κB p65表达及TNF-α分泌水平的影响。结果 LPA以剂量依赖方式促进TNF-α分泌,并可诱导THP-1细胞NF-κB p65活化,予TLR4 mAb阻断TLR4后,可显著抑制NF-κB p65表达及TNF-α分泌。结论 LPA可经由Toll4／NF-κB信号途径激活单核细胞,最终引起TNF-α等炎性因子的分泌,参与动脉粥样硬化进程。     

Polymorphism of inflammatory genes and arsenic methylation capacity are associated with urothelial carcinoma

Chronic exposure to arsenic can generate reactive oxidative species, which can induce certain proinflammatory cytokines such as tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-8 (IL-8). TNF-α, IL-6 and IL-8 have been shown to be involved in the development and progression of various cancers, including bladder cancer. This study aimed to investigate the joint effect of the polymorphism of TNF-α − 308 G/A, IL-6 − 174 G/C, IL-8 − 251 T/A and urinary arsenic profiles on urothelial carcinoma (UC) risk. This study evaluated 300 pathologically-confirmed cases of UC and 594 cancer-free controls. Urinary arsenic species were detected using high-performance liquid chromatography-linked hydride generator and atomic absorption spectrometry. The polymorphism of TNF-α − 308 G/A, IL-6 − 174 G/C and IL-8 − 251 T/A was determined using polymerase chain reaction-restriction fragment length polymorphism. The joint effects on UC risk were estimated by odds ratios and 95% confidence intervals using unconditional logistic regression. We found that the TNF-α − 308 A/A and IL-8 − 251 T/T polymorphisms were significantly associated with UC. Moreover, significant dose–response joint effect of TNF-α − 308 A/A or IL-8 − 251 T/T genotypes and arsenic methylation indices were seen to affect UC risk. The present results also showed a significant increase in UC risk in subjects with the IL-8 − 251 T/T genotype for each SD increase in urinary total arsenic and MMA%. In contrast, a significant decrease in UC risk was found in subjects who carried the IL-8 − 251 T/T genotype for each SD increase in DMA%.     

PACAP-cytokine interactions govern adrenal neuropeptide biosynthesis after systemic administration of LPS

We have examined induction of neuropeptide expression in adrenal medulla after treatment of mice with lipopolysaccharide (LPS), a model for septic shock, which activates both immune and stress responses in vivo. Messenger RNAs encoding vasoactive intestinal polypeptide (VIP) and galanin, both modulators of steroidogenesis in neighboring adrenal cortex, are up-regulated at 24 h (eight-fold for VIP and two-fold for galanin) after LPS injection, and remain elevated for the following 24 h. Up-regulation of VIP and galanin by LPS is abrogated in pituitary adenylate cyclase-activating polypeptide (PACAP)-deficient mice, suggesting an interaction between LPS, or LPS-induced cytokines, and PACAP released in adrenal medulla from the splanchnic nerve. Treatment of cultured chromaffin cells with 100 nM PACAP and 10 nM tumor necrosis factor-alpha (TNF-α), a cytokine whose production is elevated by LPS, results in long-term synergistic up-regulation of VIP and galanin mRNA. PACAP blocks the earlier induction by TNF-α of mRNA encoding inhibitor of NF-κB alpha (IκBα), normally a negative autoregulator of TNF-α signaling through nuclear factor-κB (NF-κB), without affecting the induction of TNF-α-induced protein 3 (TNFAIP3), another NF-κB-dependent gene induced by TNF-α in chromaffin cells. By acting downstream of NF-κB to inhibit IκBα gene induction by TNF-α, PACAP may block IκBα-dependent negative autoregulation of TNF-α signaling through NF-κB, prolonging TNF-α-dependent signaling to neuropeptide-encoding genes in chromaffin cells. This mechanism may also underlie PACAP-dependent neuropeptide gene induction by LPS in vivo.     

Anthocyanins from black soybean seed coats stimulate wound healing in fibroblasts and keratinocytes and prevent inflammation in endothelial cells

Wound healing is a complex process that includes inflammation, tissue formation, and remodeling. While wound healing is accompanied by inflammatory reactions, chronic inflammation impairs acute wound healing. In this study, we investigated whether anthocyanins from black soybean seed coats could stimulate wound healing while preventing excessive inflammation. At 24 h of treatment with anthocyanins, fibroblasts showed a significant increase in migration at 100 μg/mL whereas the migration of keratinocytes increased significantly at 50 and 100 μg/mL compared to control. Treatment of anthocyanins for 48 h significantly stimulated the migration of both human dermal fibroblasts and keratinocytes at 50 and 100 μg/mL concentrations. Treatment of cells with anthocyanins stimulated wound-induced VEGF production in fibroblasts and keratinocytes. However, anthocyanins inhibited ROS accumulation and VEGF production in TNF-α-stimulated endothelial cells. Furthermore, treatment of anthocyanins reduced, in a dose-dependent manner, the adhesion of inflammatory monocytes to endothelial cells. Anthocyanins also blocked both the translocation of nuclear factor-kappa B (NF-κB) p65 into the nucleus and the phosphorylation of the inhibitory factor κBα (IκBα). Thus, treatment with anthocyanins from black soybean seed coats may be a potential therapeutic strategy to promote wound healing and to prevent inflammation in a persistent inflammatory condition.     

Inhibition of inflammatory mediators by polyphenolic plant extracts in human intestinal Caco-2 cells

The mitogen-activated protein kinases (MAPK) and nuclear factor κB (NF-κB) are involved in transduction cascades that play a key role in inflammatory response. We tested the ability of preselected natural polyphenolic extracts (grape seed, cocoa, sugar cane, oak, mangosteen and pomegranate) to modulate intestinal inflammation using human intestinal Caco-2 cells treated for 4 h with these extracts and then stimulated by cytokines for 24 or 48 h. The effect of polyphenolic extracts, at 50 μmol of gallic acid equivalent/l, was investigated on inflammation-related cellular events: (i) NF-κB activity (cells transfected with a NF-κB-luciferase construct), (ii) activation of Erk1/2 and JNK (western blotting), (iii) secretion of interleukin 8 (IL-8) (ELISA), (iv) secretion of prostaglandin (PG) E₂ (ELISA), (v) production of NO (Griess method). Results show that: (i) sugar cane, oak and pomegranate extracts inhibited NF-κB activity (from 1.6 to 1.9-fold) (P < 0.001); (ii) pomegranate slightly inhibited Erk1/2 activation (1.3-fold) (P = 0.008); (iii) oak and pomegranate decreased NO synthesis by 1.5-fold (P < 0.001) and that of IL-8 by 10.3 and 6.7-fold respectively; (iv) pomegranate and cocoa decreased PGE₂ synthesis by 4.6 (P < 0.0001) and 2.2-fold (P = 0.001), respectively. We suggest that pomegranate extract could be particularly promising in dietary prevention of intestinal inflammation.     

Fucoidan, a sulfated polysaccharide from brown algae, against myocardial ischemia-reperfusion injury in rats via regulating the inflammation response

The aim of the study was to determine the effects of fucoidan on rat myocardial ischemia-reperfusion (I/R) model and elucidate the potential mechanisms. Myocardial I/R injury was induced by the occlusion of left anterior descending coronary artery for 30 min followed by reperfusion for 2 h. After 2 h reperfusion, hemodynamics parameters were detected. Blood samples were collected to determine serum levels of tumor necrosis factor-α (TNF-α) and interleukin 6, 10 (IL-6, 10). Hearts were harvested to assess histopathological changes, infarct size (IS), and the content of myeloperoxidase (MPO). The expression of high-mobility group box 1 (HMGB1), phosphor-IκB-α and phosphor-nuclear factor kappa B (NF-κB) were assayed by western blot. Compared with control group, treatment with fucoidan improved left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP) and the contractility index (P < 0.05, P < 0.01). Fucoidan reduced the myocardial IS, the levels of TNF-α and IL-6, and the activity of MPO (P < 0.05, P < 0.01). Fucoidan down-regulated the expression of HMGB1, phosphor-IκB-α and NF-κB, but increased the content of IL-10 when compared with control (P < 0.05, P < 0.01). Besides, the infiltration of polymorph nuclear leukocytes (PMNs) and histopathological damages in myocardium were decreased in fucoidan treated groups (PMNs, P < 0.05, P < 0.01). These findings revealed that the administration of fucoidan could regulate the inflammation response via HMGB1 and NF-κB inactivation in I/R-induced myocardial damage.     

Effect of baicalin on toll-like receptor 4-mediated ischemia/reperfusion inflammatory responses in alcoholic fatty liver condition

Alcoholic fatty liver is susceptible to secondary stresses such as ischemia/reperfusion (I/R). Baicalin is an active component extracted from Scutellaria baicalensis, which is widely used in herbal preparations for treatment of hepatic diseases and inflammatory disorders. This study evaluated the potential beneficial effect of baicalin on I/R injury in alcoholic fatty liver. Rats were fed an alcohol liquid diet or a control isocaloric diet for 5 weeks, and then subjected to 60 min of hepatic ischemia and 5 h of reperfusion. Baicalin (200 mg/kg) was intraperitoneally administered 24 and 1 h before ischemia. After reperfusion, baicalin attenuated the increases in serum alanine aminotransferase activity, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) levels in alcoholic fatty liver. The increased levels of TNF-α and IL-6 mRNA expression and inducible nitric oxide synthase and cyclooxygenase-2 protein and mRNA expressions increased after reperfusion, which were higher in ethanol-fed animals, were attenuated by baicalin. In ethanol-fed animals, baicalin attenuated the increases in toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 protein expressions and the nuclear translocation of NF-κB after reperfusion. In conclusion, our findings suggest that baicalin ameliorates I/R-induced hepatocellular damage by suppressing TLR4-mediated inflammatory responses in alcoholic fatty liver.     

Suppression of adhesion molecule expression by phenanthrene-containing extract of bulbils of Chinese Yam in vascular smooth muscle cells through inhibition of MAPK,Akt and NF-κB

Atherosclerosis is a chronic inflammatory disease associated with increased expression of adhesion molecules in vascular smooth muscle cells (VSMCs). The objective of this study was to examine the in vitro effects of extract from aerial Bulbil of Dioscorea batatas Decne (Db-Ex) on the ability to suppress the expression of adhesion molecules induced by TNF-α. We also identified bioactive components from a methanol extract. VSMCs pre-exposed to Db-Ex (10–100 μg/ml) were stimulated with TNF-α (10 ng/ml). Preincubation of VSMCs for 2 h with Db-Ex dose-dependently inhibited TNF-α-induced adhesion of THP-1 monocytic cells and mRNA and protein expression of vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Db-Ex treatment decreased ROS production and the amount of phosphorylated form of p38, ERK, JNK and Akt in TNF-α-stimulated cells, suggesting that Db-Ex inhibits adhesion molecule expression possibly through MAPK and Akt regulation. Db-Ex also suppressed TNF-α-activation NK-κB. This effect was mediated through degradation of IκBα and nuclear translocation of the p65 subunit of NF-κB. These results suggest that Db-Ex inhibits monocyte adhesion and the TNF-α-mediated induction of adhesion molecules in VSMC by downregulating the MAPK/Akt/NF-κB signaling pathway, which may explain the ability of Db-Ex to suppress inflammation within the atherosclerotic lesion.     

FK228对HepG2细胞NF-κB活化及炎症因子转录的影响

目的:研究FK228对TNF-α诱导的人肝癌细胞HepG2核转录因子κB(nuclear factor-κB,NF-κB)活化及炎症因子IL-6、IL-8转录的影响。方法:培养的HepG2细胞分为对照组、TNF-α刺激组和FK228干预组。分别用TNF-α刺激和FK228+TNF-α共同作用,免疫印迹(Western blot)法分析细胞核中NF-κBp65及其细胞浆中抑制因子IκBα的表达;RT-PCR对炎症因子IL-6、IL-8 mRNA作半定量分析。结果:FK228(4～32μg·L~(-1))干预组与TNF-α刺激组比较,细胞核内NF-κB显著减少(P<0.01);FK228(8～32μg·L~(-1))减少胞浆中IκBα的降解且各组之间差异有统计学意义(P<0.01);FK228降低TNF-α诱导的IL-6、IL-8 mRNA表达,FK228干预组与TNF-α刺激组相比,差异具统计学意义(P<0.01)。结论:FK228减少胞浆中IκBα降解、阻碍NF-κB的过度活化可能是降低炎症因子释放、发挥抗炎作用的重要机制。     

Tributyltin-induced endoplasmic reticulum stress and its Ca-mediated mechanism

Organotin compounds, especially tributyltin chloride (TBT), have been widely used in antifouling paints for marine vessels, but exhibit various toxicities in mammals. The endoplasmic reticulum (ER) is a multifunctional organelle that controls post-translational modification and intracellular Ca^2 + signaling. When the capacity of the quality control system of ER is exceeded under stress including ER Ca^2 + homeostasis disruption, ER functions are impaired and unfolded proteins are accumulated in ER lumen, which is called ER stress. Here, we examined whether TBT causes ER stress in human neuroblastoma SH-SY5Y cells. We found that 700 nM TBT induced ER stress markers such as CHOP, GRP78, spliced XBP1 mRNA and phosphorylated eIF2α. TBT also decreased the cell viability both concentration- and time-dependently. Dibutyltin and monobutyltin did not induce ER stress markers. We hypothesized that TBT induces ER stress via Ca^2 + depletion, and to test this idea, we examined the effect of TBT on intracellular Ca^2 + concentration using fura-2 AM, a Ca^2 + fluorescent probe. TBT increased intracellular Ca^2 + concentration in a TBT-concentration-dependent manner, and Ca^2 + increase in 700 nM TBT was mainly blocked by 50 μM dantrolene, a ryanodine receptor antagonist (about 70% inhibition). Dantrolene also partially but significantly inhibited TBT-induced GRP78 expression and cell death. These results suggest that TBT increases intracellular Ca^2 + concentration by releasing Ca^2 + from ER, thereby causing ER stress.     

Preventive effect of Coptis chinensis and berberine on intestinal injury in rats challenged with lipopolysaccharides

Coptis chinensis has been used in traditional Chinese medicine to treat inflammatory symptoms. Berberine is the main alkaloid compound of C. chinensis. This study utilized a typical lipopolysaccharide (LPS) injured model to investigate the effects of C. chinensis aqueous extract (CCAE) and berberine (major active ingredient in CCAE) in the gut-derived sepsis. In rats, pretreatment with different doses of berberine (30 or 120 mg/kg bw, i.g.; BBR30 or BBR120) or CCAE (containing 9.9% berberine; 300 mg/kg bw, i.g.; CCAE300) prior to the administration of LPS (20 mg/kg bw, i.p.) significantly suppressed the increased tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and nitrite oxide (NO) in plasma as well as the activation of toll-like receptor 4 (TLR4) and nuclear factor-κB (NF-κB) in ileum. In addition, CCAE300 and BBR30 markedly elevated the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px); significantly prevented the increased malondialdehyde (MDA), NO and villi injury in ileum compared with the negative control. Collectively, CCAE300 and BBR30 reduced the LPS-induced intestinal damage by elevating the activities of SOD and GSH-Px and by suppressing the activation of TLR4 and NF-κB in ileum. These results indicate that CCAE and berberine are promising agents for preventing sepsis and its complications.     

Supercritical fluid extraction of oregano (Origanum vulgare) essentials oils: Anti-inflammatory properties based on cytokine response on THP-1 macrophages

Two fractions (S1 and S2) of an oregano (Origanum vulgare) extract obtained by supercritical fluid extraction have been used to test anti-inflammatory effects on activated human THP-1 cells. The main compounds present in the supercritical extract fractions of oregano were trans-sabinene hydrate, thymol and carvacrol. Fractions toxicity was assessed using the mitochondrial-respiration-dependent 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) reduction method for several concentrations during 24 and 48 h of incubation. Concentrations higher than 30 μg/mL of both supercritical S1 and S2 oregano fractions caused a reduction in cell viability in a dose-dependent manner. Oxidized-LDLs (oxLDLs) activated THP-1 macrophages were used as cellular model of atherogenesis and the release/secretion of cytokines (TNT-α, IL-1β, IL-6 and IL-10) and their respective mRNA expressions were quantified both in presence or absence of supercritical oregano extracts. The results showed a decrease in pro-inflammatory TNF-α, IL-1β and IL-6 cytokines synthesis, as well as an increase in the production of anti-inflammatory cytokine IL-10. These results may suggest an anti-inflammatory effect of oregano extracts and their compounds in a cellular model of atherosclerosis.     

Sertraline ameliorates inflammation in CUMS mice and inhibits TNF-α-induced inflammation in microglia cells

Evidence indicates that inflammation plays a crucial role in depression. Therefore, new antidepressants might be identified by screening drugs for their anti-inflammatory actions. Sertraline hydrochloride (SERT), a widely used antidepressant, has anti-inflammatory effects in clinical studies, but the mechanism involved is unclear. In this study, we used cell and molecular biology to determine the possible anti-inflammatory mechanism of SERT in vivo and in vitro. Experimental data from the in vivo study showed that mice exposed to chronic unpredictable mild stress (CUMS) had significantly higher levels of major inflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin-1β [IL-1β] and inducible nitric oxide synthase [iNOS]) in peripheral and central tissues compared with the control group. Treatment of CUMS mice with SERT significantly reduced the levels of these inflammatory cytokines and inhibited the phosphorylation of nuclear factor-κB (NF-κB) and nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκB-α). Moreover, SERT reduced serum levels of transaminase in CUMS mice. Our in vitro study revealed that SERT suppressed TNF-α-induced NF-κB activation in a dose-dependent manner. SERT also inhibited the TNF-α-induced nuclear translocation of NF-κB by inhibiting IκB-α phosphorylation. Furthermore, SERT inhibited TNF-α-induced inflammatory cytokines in BV2 microglia cells. SERT directly bound to TNF-α and TNF-α receptor 1 (TNFR1) to potently block TNF-α/TNFR1-triggered signaling. These results indicate that SERT might treat depression by inhibiting the activation of microglia via the NF-κB signaling pathway. This study provides a basis for the research and development of antidepressants that act to reduce inflammation and the expression of inflammatory mediators.     

五灵胶囊有效成分对脂多糖诱导大鼠枯否细胞核因子的影响

目的观察五灵胶囊中有效成分对脂多糖（LPS）诱导大鼠枯否细胞核因子（NF-κB）的调节作用。方法分离大鼠肝细胞和枯否细胞,60μg·L~（-1）LPS诱导枯否细胞分泌促炎因子及NO。采用^125Ⅰ放射免疫测定法测定TNFα、IL-6、IL-8水平,比色法测定NO生成量,Western blot法检测ERK、p-ERK、NF-κB P50、NF-κB P65、p-NF-κB P65、IκB、p-IκB、IKK、P38、p-P38、CD14、Stat3蛋白的变化。结果五灵胶囊中的有效成分可显著抑制LPS诱导枯否细胞分泌TNF-α、IL-6、IL-8、NO的生成量。结论五灵胶囊有效成分能抑制枯否细胞释放促炎因子,是其治疗慢性肝炎的作用机制之一。     

βγ-CAT, a non-lens βγ-crystallin and trefoil factor complex from amphibian skin secretions, caused endothelium-dependent myocardial depression in isolated rabbit hearts

Previous in vivo study demonstrated that βγ-CAT, a newly identified non-lens βγ-crystallin and trefoil factor complex from frog Bombina maxima skin secretions, possessed potent lethal toxicity on mammals resulted from hypotension and cardiorespiratory arrest. However, the mechanism of cardiac dysfunction induced by the protein is unknown. Here, we report that βγ-CAT, with dosages of 0.8-3.0 nM, elicited an acute negative inotropic effect in isolated rabbit heart Langendorff preparations, which mimicked acute heart failure. In addition, the effect of βγ-CAT on the hearts was mediated by endothelium-dependent coronary vasoconstriction (P < 0.01, compared between endothelium-intact and removal hearts). After βγ-CAT (3.0 nM) treatment, the positive signal of tumor necrosis factor-α (TNF-α) was detected mainly around the endothelial cell layer as detected by in situ indirect immunofluorescence, indicating that the release of TNF-α occurred. At the same time, a rapid TNF-α release was detected in primary cultured rabbit endocardial endothelial cells (REECs) treated with βγ-CAT. After addition of βγ-CAT (3.0 nM) for 10 min and 30 min, the TNF-α levels were increased to 57.33 ± 3.22 pg/ml and 60.00 ± 5.35 pg/ml (P < 0.05, compared with the control values of 21.67 ± 3.45 pg/ml and 33.70 ± 6.24 pg/ml, respectively). At high concentrations, βγ-CAT interfered with the cell viability of REECs (CC₅₀ about 25 nM). Taken together, βγ-CAT was able to induce acute myocardial depression and the toxic effect might be partially explained by the release of TNF-α. The finding provides new information to understand the patho-physiological roles of non-lens βγ-crystallins and trefoil factors.