Synergistic antiinflammatory effect of NF-kappaB inhibitors and steroidal or non steroidal antiinflammatory drugs in the pleural inflammation induced by carrageenan in mice

Particulate Matter 2.5 Induced Developmental Cardiotoxicity in Chicken Embryo and Hatchling

Particulate matter poses health risk to developing organisms. To investigate particulate matters with a diameter smaller than 2.5 um (PM2.5)-induced developmental cardiotoxicity, fertile chicken eggs were exposed to PM2.5 via air cell injection at doses of 0.05, 0.2, 0.5, 2, and 5 mg/egg kg. Morphological changes in the embryonic day four (ED4) and hatchling hearts were assessed with histological techniques. Heart rates of hatchling chickens were measured with electrocardiography. The protein expression levels of nuclear factor kappa-light-chain-enhancer of activated B cells p65 (NF-kb p65), inducible nitric oxide synthase (iNOS), and matrix metallopeptidase 9 (MMP9) were assessed with immunohistochemistry or western blotting in hatchling hearts. PM2.5 exposure elevated areas of heart in ED4 embryo, increased heart rate, and thickened right ventricular wall thickness in hatchling chickens. Immunohistochemistry revealed enhanced NF-kb p65 expression in hatchling hearts. Western blotting results indicated that both iNOS and MMP9 expression were enhanced by lower doses of PM2.5 exposure (0.2 and 0.5 mg/kg) but not 2 mg/kg. In summary, developmental exposure to PM2.5 induced developmental cardiotoxicity in chicken embryo and hatchling chickens, which is associated with NF-kb p65, iNOS, and MMP9.

Design and synthesis of 1,3-benzothiazinone derivatives as potential anti-inflammatory agents

A series of 1,3-benzothiazinone derivatives were designed and synthesized for pharmacological assessments. Among the synthesized 19 compounds, some compounds showed high activities on inhibiting LPS-induced nitrite oxide and TNF-α production, down-regulating COX-2 and increasing IL-10 production in RAW264.7 cells. All the compounds had no obvious cytotoxicity in in vitro assay. LD₅₀ value of compound 25 was greater than 2000 mg/kg, which was safer than meloxicam. Compound 25 significantly inhibited phosphorylation of NF-κB and STAT3 in LPS-induced RAW264.7 cells. Inhibition of synthesized compounds on COX activity was weaker than meloxicam. Compound 25 displayed lower gastrointestinal toxicity than meloxicam. Besides, compound 25 decreased the swelling in carrageenan-induced paw edema models of inflammation and reduced PGE₂ level significantly. In summary, 1,3-benzothiazinone derivatives are unique scaffolds with anti-inflammatory activity and low toxicity.

RNA-seq profiles of chicken type II pneumocyte in response to Escherichia coli infection

Avian pathogenic Escherichia coli (APEC) causes great economic loss to the poultry industry worldwide. Chicken type II pneumocytes (CP II cells) secrete surfactants and modulate lung immunity to decrease the infection of the invading pathogen. Nevertheless, the pathogenesis of CP II cells to APEC infection remains poorly understood. Therefore, we conducted global gene expression profiling of CP II cells after APEC-O78 infection to explore the host-pathogen interaction. The differentially expressed genes of CP II cells to APEC infection were characterized by RNA-seq with EB-seq algorithm. In consequence, the mRNA of 18996 genes was identified, and CP II cells responded to APEC infection with marked changes in the expression of 1390 genes. Among them, there are 803 down-regulated mRNAs and 587 up-regulated mRNAs. The KEGG prediction and Gene Ontology terms analysis revealed that the major enriched pathways were related to NF-κB signaling pathway, apoptosis pathway, tight junction, and cytokine-cytokine receptor interaction and other pathways. We adopted qRT-PCR to verify the validity of the selected gene expression. The fold induction of qPCR was similar to the RNA-seq results. These results provide a better understanding of the pathogenesis of APEC, especially apoptosis pathway involved in APEC infection.

Emerging concepts in pleural infection

PURPOSE OF REVIEW

Pleural infection remains an important pulmonary disease, causing significant morbidity and mortality. There is a resurgence of disease burden despite introduction of antibiotics and pneumococcal vaccines. A revisit of the pathogenesis and update on intervention may improve the care of pleural infection.

RECENT FINDINGS

Recent studies have uncovered the prognostic implication of the presence of a pleural effusion in patients with pneumonia. Identifying where the bacteria lives may have diagnostic and therapeutic implications. Over-exaggerated pleural inflammation may underlie development of parapneumonic effusion as indirect evidence and a randomized study in children raised a role of corticosteroids in parapneumonic pleural effusions, but data are lacking for adults. Optimization of the delivery regimen of intrapleural fibrinolytic and deoxyribonuclease therapy is ongoing.

SUMMARY

The review aims to review the current practice and explore new directions of treatment on pleural infection.

Applications of the hexanic fraction of Agave sisalana Perrine ex Engelm (Asparagaceae): control of inflammation and pain screening

The present study evaluated the anti-inflammatory and analgesic properties of Agave sisalana Perrine in classic models of inflammation and pain. The hexanic fraction of A. sisalana (HFAS) was obtained by acid hydrolysis followed by hexanic reflux. Anti-inflammatory properties were examined in three acute mouse models (xylene ear oedema, hind paw oedema and pleurisy) and a chronic mouse model (granuloma cotton pellet). The antinociceptive potential was evaluated in chemical (acetic-acid) and thermal (tail-flick and hot-plate test) models of pain. When given orally, HFAS (5, 10, 25 and 50 mg/kg) reduced ear oedema (p < 0.0001; 52%, 71%, 62% and 42%, respectively). HFAS also reduced hind paw oedema at doses of 10 mg/kg and 25 mg/kg (p < 0.05; 42% and 58%, respectively) and pleurisy at doses of 10 mg/kg and 25 mg/kg (41% and 50%, respectively). In a chronic model, HFAS reduced inflammation by 46% and 58% at doses of 10 mg/kg and 25 mg/kg, respectively. Moreover, this fraction showed analgesic properties against the abdominal writhing in an acetic acid model (at doses of 5-25 mg/kg) with inhibitory rates of 24%, 54% and 48%. The HFAS also showed an increased latency time in the hot-plate (23% and 28%) and tail-flick tests (61% and 66%) for the 25 mg/kg and 50 mg/kg doses, respectively. These results suggest that HFAS has anti-inflammatory and analgesic properties.

Nuclear factor-κB: a key regulator in health and disease of lungs

Rel/NF-κB transcription factors play a key role in modulating the response of immunoregulatory genes including cytokines and chemokines, cell adhesion molecules, acute phase proteins, and anti-microbial peptides. Furthermore, an array of genes important for angiogenesis, tumor invasion and metastasis is also regulated by nuclear factor-κB (NF-κB). Close association of NF-κB with inflammation and tumorigenesis makes it an attractive target for basic research as well as for pharmaceutical industries. Studies involving various animal and cellular models have revealed the importance of NF-κB in pathobiology of lung diseases. This review (a) describes structures, activities, and regulation of NF-κB family members; (b) provides information which implicates NF-κB in pathogenesis of pulmonary inflammation and cancer; and (c) discusses information about available synthetic and natural compounds which target NF-κB or specific components of NF-κB signal transduction pathway and which may provide the foundation for development of effective therapy for lung inflammation and bronchogenic carcinomas.

Protective effect of gastrin-releasing peptide receptor antagonist in carrageenan-induced pleural inflammation in rats

OBJECTIVE

We report the effects of the gastrin-releasing peptide (GRP) receptor antagonist RC-3095 in an acute inflammation model induced by carrageenan.

METHODS

Male Wistar rats received saline or saline containing 2% lambda-carrageenan into the pleural cavity, with some also receiving RC-3095 3 mg/kg subcutaneously, immediately after surgery. Four hours later, the rats were killed and pleural exudate was obtained for evaluation of total cell count, lactate dehydrogenase activity, total protein, cytokines analysis and nitrite/nitrate concentrations; myeloperoxidase (MPO) activity and oxidative stress were evaluated in the lung.

RESULTS

RC-3095 exhibited pronounced anti-inflammatory actions by inhibition of leukocyte influx and blockade of MPO, nitrite/nitrate and cytokine levels. Moreover, the results showed that RC-3095 elicits action against oxidative damage in lipids and proteins, as well as increasing cell viability.

CONCLUSION

The present findings suggest that GRP plays a role in acute inflammation that can be related with the reduction of oxidative damage and that it could be effective in therapeutic applications.

Curcumin reverses attenuated carbachol-induced contraction of the colon in a rat model of colitis

BACKGROUND

Curcumin ameliorates colitis whether it reverses colitis-induced reduction in colonic contractility remains to be investigated.

OBJECTIVES

To investigate the effect of curcumin on colitis-induced reduction of carbachol-induced contraction in colon segments from rats treated with trinitrobenzenesulphonic acid.

METHODS

Colitis was induced in rats by intra rectal administration of trinitrobenzenesulphonic acid and followed for 5 days. A group of animals which received trinitobenzene sulphonic acids was treated with curcumin (100 mg/Kg and 200 mg/kg body weight) 2 hrs prior to induction of colitis. The controls received phosphate buffered saline in a similar fashion. Markers of inflammation and contractility of colon were assayed using standard procedures.

RESULTS

Induction of colitis was associated with increased myeloperoxidase activity and malondialdehyde levels, gross histological changes characterized by infiltration of inflammatory cells. All these changes were prevented by treatment with curcumin (100 mg/kg). Treatment with curcumin also reduced the histological scores from 3.34+/-0.40 to 1.75+/-0.30 confirming an anti-inflammatory effect of curcumin in this experimental model of colitis. Colonic reactivity to carbachol was decreased in colitis affecting the maximum response but not sensitivity. Treatment with curcumin had no effect on sensitivity of the colon to carbachol in any of the preparations. Curcumin however reversed the decrease in carbachol-induced contraction associated with trinitrobenzenesulphonic acid treatment. The same dose of curcumin had no effect on either the potency of or the maximum response to carbachol in control rats. Tissue expression of NF-kB was increased in colon segments from trinitrobenzenesulphonic acid -treated rats and this was inhibited in rats treated with curcumin.

CONCLUSIONS

Based on these findings it is concluded that curcumin prevented the reduction in carbachol-induced contraction in trinitrobenzenesulphonic acid -treated rats by modulating NF-kB signaling pathway.

Efficacy of sulphasalazine on lung histopathology in a murine model of chronic asthma

Sulphasalazine is a specific inhibitor of nuclear factor kappa B (NF-kappa B) which plays a key role in asthma. To determine the impact of sulphasalazine in the treatment of chronic asthma, BALB/c mice were sensitized and challenged with ovalbumin. Mice with experimentally induced asthma in group I received saline, group II sulphasalazine 200 mg/kg, group III sulphasalazine 300 mg/kg, and group IV dexamethasone 1 mg/kg intraperitoneally once a day in the last 7 days of the challenge period. Histological findings of the airways were evaluated by light and electron microscopies. Dexamethasone and sulphasalazine in both doses significantly improved all airway histopathologic parameters of asthma except numbers of goblet cells. Both doses of sulphasalazine improved thicknesses of basement membrane better than dexamethasone. Dexamethasone reduced the number of mast cells better than sulphasalazine (200 mg/kg). Further studies are needed to evaluate the efficacy of sulphasalazine in the treatment of asthma.

Anti-inflammatory effects of isoflavone powder produced from soybean cake

Soybean cake, a byproduct obtained during the processing of soybean oil, has been shown to be a rich source of isoflavones. The objectives of this study were to use soybean cake as raw material for processing into powder and to evaluate the anti-inflammatory activity. Eleven treatments, including powders of malonylglucoside, glucoside, acetylglucoside, aglycone, ISO-1, and ISO-2, as well as genistein standard, gamma-PGA, control, normal, and PDTC, were used for evaluation. A total of 77 mice were each provided daily with tube feeding for 4 weeks at a dose of 0.3 mL of aqueous solution from each treatment, and inflammation was induced with intraperitoneal injection of 1 mg/kg of body weight lipopolysaccharide (LPS). Results showed that all of the isoflavone powders and genistein standard were effective in inhibiting LPS-induced inflammation, lowering leukocyte number in mice blood and reducing production of IL-1beta, IL-6, NO, and PGE2 in both peritoneal exudate cell supernatant and peritoneal exudate fluid. All of the isoflavone treatments failed to retard T cell proliferation; however, both ISO-1 and ISO-2 could inhibit B cell proliferation. The difference in anti-inflammatory activity was minor between any of the isoflavone treatments.

Ameliorative effect of pyrrolidinedithiocarbamate on acetic acid-induced colitis in rats

Ulcerative colitis is a chronically recurrent inflammatory bowel disease of unknown origin. The present study examined the effect of NF-kappaB inhibitor and antioxidant, pyrrolidinedithiocarbamate (PDTC) on experimental ulcerative colitis in rats. Animals were randomly divided into 4 groups, each consisting of 6 animals; normal control group, acetic acid group, PDTC-treated group and sulfasalazine-treated group as a positive control group. Induction of colitis by intracolonic administration of 3% acetic acid produced severe macroscopic inflammation in the colon 24 h after acetic acid administration as assessed by the colonic damage score. Microscopically, colonic tissues showed ulceration, oedema and inflammatory cells infiltration. Biochemical studies revealed increased serum levels of lactate dehydrogenase (LDH), and nitrite/nitrate and colonic concentrations of tumor necrosis factor-alpha (TNF-alpha) and the neutrophil infiltration index, myeloperoxidase (MPO). Oxidative stress was indicated by elevated lipid peroxides formation and depleted reduced glutathione concentrations (GSH) in colonic tissues. Immunohistochemical studies of colonic sections revealed upregulation of inducible nitric oxide synthase (iNOS). Pretreatment with PDTC at a dose of (200 mg/kg/day, i.p.), three days before induction of colitis decreased serum LDH, nitrite/nitrate and TNF-alpha levels, colonic concentrations of MPO and lipid peroxides while increased colonic GSH concentration. Moreover, PDTC pretreatment attenuated colonic iNOS expression. Finally, histopathological changes were nearly restored by PDTC pretreatment. The findings of the present study provide evidence that PDTC may be beneficial in patients with inflammatory bowel disease.

Resident pleural macrophages are key orchestrators of neutrophil recruitment in pleural inflammation

RATIONALE

The role played by resident pleural macrophages in the initiation of pleural inflammation is currently unclear.

OBJECTIVE

To evaluate the role of resident pleural macrophages in the initiation of inflammation.

METHODS

We have used a conditional macrophage ablation strategy to determine the role of resident pleural macrophages in the regulation of neutrophil recruitment in a murine model of experimental pleurisy induced by the administration of carrageenan and formalin- fixed Staphylococcus aureus.

MEASUREMENTS AND MAIN RESULTS

Conditional macrophage ablation mice express the human diphtheria toxin receptor under the control of the CD11b promoter such that the administration of diphtheria toxin induces ablation of nearly 97% of resident macrophages. Ablation of resident pleural macrophages before the administration of carrageenan or S. aureus dramatically reduced neutrophil influx into the pleural cavity. In the carrageenan model, the reduction in neutrophil infiltration was associated with marked early reduction in the level of macrophage inflammatory protein 2 as well as reduced levels of various cytokines, including tumor necrosis factor alpha, interleukin 6, and interleukin 10. Adoptive transfer of nontransgenic macrophages partially restored neutrophil infiltration. We also stimulated macrophage-depleted and nondepleted pleural cell populations with carrageenan in vitro and determined the production of chemokines and cytokines. Chemokine and cytokine production was markedly reduced by macrophage depletion, reinforcing the role of resident pleural macrophages in the generation of mediators that initiate acute inflammation.

CONCLUSION

These studies indicate a critical role for resident pleural macrophages in sensing perturbation to the local microenvironment and orchestrating subsequent neutrophil infiltration.

Inhibiton of NF-kappaB activation during ischemia reduces hepatic ischemia/reperfusion injury in rats

The aim of this study was to determine whether nuclear factor-kappaB (NF-kappaB) inhibitors are efficient against hepatic ischemia/reperfusion (I/R) injury. We previously demonstrated that xanthine oxidase-derived reactive oxygen species activate NF-kappaB during ischemia. However, the role of NF-kappaB activation during ischemia in post-reperfusion injury remains unclear. Therefore, while we examined the effects of NF-kappaB inhibitors, sulfasalazine and pyrrolidinedithiocarbamate on hepatic I/R injury using a rat lobar hepatic I/R model, we estimated the relationship between NF-kappaB activation during ischemia and following hepatic damage caused by reperfusion. The portal vein and the hepatic artery were clamped for 1 hr followed by reperfusion for up to 24 hr. NF-kappaB activation was determined by Western blot analysis. NF-kappaB activation was observed in the ischemic lobe of the liver, and the activation was prevented by pre-administration with NF-kappaB inhibitors. Although the serum ALT level, hepatic MPO activity and BSP clearance, as an index of hepatic injury, were increased after reperfusion, the increase was attenuated by pre-administration with NF-kappaB inhibitors. These findings suggest that NF-kappaB activation during ischemia is relevant to hepatic I/R injury. Moreover, we first showed that pre-administration with NF-kappaB inhibitors is effective against hepatic I/R injury.

Pathogenesis of the eosinophilic pleural effusions

PURPOSE OF REVIEW

Eosinophilic pleural effusions (EPE) are defined as those that contain at least 10% eosinophils. EPEs account for 5 to 16% of exudative pleural effusions. However, their pathogenesis is poorly understood. The purpose of this review is to discuss the mechanisms that lead to eosinophilic pleural inflammation.

RECENT FINDINGS

Eosinophilic pleural effusions are caused by the presence of air or blood or both in the pleural space, infectious or other inflammatory diseases, malignancy, pulmonary emboli, asbestos exposure, and drug reactions. Differences in the clinical features suggest that a variety of mechanisms operate to induce eosinophilic pleural inflammation and pleural fluid accumulation. Human and animal studies indicate that interleukin (IL)-5 is an important common contributor of different pathogenetic pathways. The possible role of other cytokines, chemokines, and adhesion molecules in the development of EPE is under investigation.

SUMMARY

Understanding the pathogenesis of EPE will permit the development of novel therapies for the persistent, symptomatic, posttraumatic and idiopathic EPE. Anti-IL-5 treatment is an interesting option that requires further research.

Decrease in activity of smooth muscle L-type Ca2+ channels and its reversal by NF-kappaB inhibitors in Crohn's colitis model

We investigated the mechanisms of dysmotility of the colonic circular muscle of the Crohn's disease rat model. Contractions induced by KCl, carbachol, and Bay K 8644 were decreased in circular smooth muscles isolated from 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis rat colon. However, the absolute force and Ca2+ sensitivity of contractile proteins were not affected as assessed in alpha-toxin permeabilized smooth muscle. The current density of the L-type Ca2+ channel in circular smooth muscle cells was significantly decreased in the TNBS-treated colonic cells. However, expressions of the L-type Ca2+ channel mRNA and protein did not differ between control and TNBS-treated preparations. Pretreatment with the NF-kappaB inhibitors pyrrolidinedithiocarbamate and sulfasalazine partially recovered the decreased contractility and current density of the L-type Ca2+ channel by TNBS treatment. These results suggest that the decrease in the contraction of circular smooth muscle isolated from TNBS-induced colitis rat colon, which may be related to gut dysmotility in Crohn's disease, is attributable to the decreased activity of the L-type Ca2+ channel. The dysfunction of the L-type Ca2+ channel may be mediated by NF-kappaB-dependent pathways.

Molecular and pharmacological evidence for modulation of kinin B(1) receptor expression by endogenous glucocorticoids hormones in rats

1. The effect of endogenous glucocorticoid hormones on the expression of rat B(1) receptors was examined by means of molecular and pharmacological functional approaches. 2. Rats were adrenalectomized (ADX), and 7 days after this procedure the intradermal injection of B(1) receptor agonist des-Arg(9)-BK produced a significant increase in the paw volume, while only a weak effect was observed in sham-operated animals. A similar increase in the contractile responses mediated by B(1) agonist des-Arg(9)-BK was also observed in the rat portal vein in vitro. 3. Chemical ADX performed with mitotane (a drug that reduces corticosteroid synthesis) produced essentially the same up-regulation of B(1) receptors as that observed in ADX rats. 4. The modulation of B(1) receptor expression was evaluated by ribonuclease protection assay, employing mRNA obtained from the lungs and paw of ADX rats. 5. Additionally, both paw oedema and contraction of portal vein mediated by B(1) agonist des-Arg(9)-BK in ADX rats, were markedly inhibited by treatment with dexamethasone, or COX-2 inhibitor meloxican, or with the NF-kappaB inhibitor PDTC. Interestingly, the same degree of inhibition was achieved when the animals were treated with a combination of submaximal doses of dexamethasone and PDTC. 6. The involvement of NF-kappaB pathway was further confirmed by mobility shift assay using nuclear extracts from lung, paw and heart of ADX rats. It was also confirmed that the treatment of ADX rats with dexamethasone, PDTC or dexamethasone plus PDTC completely inhibit NF-kappaB activation caused by absence of endogenous glucucorticoid. 7. Together, the results of the present study provide, for the first time, molecular and pharmacological evidence showing that B(1) kinin receptor expression can be regulated through endogenous glucocorticoids by a mechanism dependent on NF-kappaB pathway. Clinical significance of the present findings stem from evidence showing the importance of B(1) kinin receptors in the mediation of inflammatory and pain related responses.