地榆、白芷、白蔹在溃疡性结肠炎大鼠中的作用及机制探讨

目的探讨地榆、白芷、白蔹对溃疡性结肠炎大鼠血清中IL-1β、IL-10水平及肠组织中NF-κB表达的影响。方法将48只成年SD大鼠随机分为正常组、模型组、地榆组、白芷组、白蔹组、巴柳氮钠组,每组各8只。除正常组外,其余各组制备大鼠结肠炎模型。造模成功后,各组予相应处理,检测大鼠血清中IL-1β、IL-10含量及大鼠结肠组织中NF-κB p65蛋白水平。结果地榆组、白芷组、巴柳氮钠组大鼠血清中IL-1β水平均明显低于模型组。地榆组、白芷组、巴柳氮钠组血清中IL-10水平较模型组显著升高。与模型组相比,各中药治疗组、巴柳氮钠组大鼠结肠组织中NF-κB p65蛋白表达均明显下调。结论地榆、白芷、巴柳氮钠均可显著降低IL-1β水平,升高IL-10水平,明显下调NF-κB蛋白活性。     

Macrophage migration inhibitory factor in the sera and at the colonic mucosa in patients with ulcerative colitis: clinical implications and pathogenic significance

BACKGROUND: Inflammatory cytokines produced by activated macrophages are implicated in the pathogenesis of ulcerative colitis (UC). With the theory that macrophage migration inhibitory factor (MIF) may have a role in the accumulation of macrophages, we studied MIF in UC. MATERIALS AND METHODS: A total of 27 patients with UC, 14 patients with Crohn's diseases (CD), 11 patients with other forms of colitis and 26 normal controls were enrolled in the study. The levels of MIF in the sera and culture supernatant were measured by an enzyme-linked immunosorbent assay. MIF, macrophages and T cells were localized at the colonic mucosa by immunohistochemistry. RESULTS: The levels of MIF in the sera were significantly higher in UC than in normal controls (P < 0.05), in serum C-reactive protein (CRP) -positive cases with UC than in CRP-negative cases with UC (P < 0.05), and in patients with severe colitis with UC than in mild colitis with UC (P < 0.05). There was a positive relationship between serum MIF levels with the CRP levels and activities of colitis. However, the levels of MIF in patients with CD and other forms of colitis were not significantly different from their levels in normal controls and UC. Infiltrating cells at the colonic mucosa in UC and CD expressed MIF. CONCLUSIONS: These data suggest a role of MIF in the pathogenesis of UC. MIF may be used as a marker of disease activity in UC and control of MIF production may have therapeutic implications.     

Positive zinc intake and a Japanese diet rich in n-3 fatty acids induces clinical remission in patients with mild active ulcerative colitis: a randomized interventional pilot study

Zinc intake has reduced hospitalizations in patients with ulcerative colitis (UC), highlighting the need to maintain blood zinc levels. This prospective study investigated whether the promotion of zinc intake and a Japanese diet (high in n-3 fatty acids) could induce clinical remission in patients with mild active UC. Patients with mild active UC were randomly assigned to either (1) continue an unrestricted diet or (2) receive nutritional guidance promoting zinc intake and a Japanese diet. The primary endpoint was clinical remission at 24 weeks. Secondary endpoints were the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) scores, Clinical Activity Index (CAI), Geboes Histopathology Score (GHS), and biomarkers, including zinc levels, measured at 12 and 24 weeks. Nutritional assessments were performed using the Food Frequency Questionnaire. The CAI, UCEIS, and GHS scores were significantly lower in the intervention group than in the control group, with a significantly higher proportion of patients achieving clinical remission. Furthermore, the intervention group exhibited weight gain and significantly increased blood zinc levels. The combination of promoting dietary zinc intake and a Japanese diet rich in n-3 fatty acids can induce clinical remission in patients with mild active UC.     

The correlation between NF-κB inhibition and disease activity by coadministration of silibinin and ursodeoxycholic acid in experimental colitis

NF‐κB is one of the most important nuclear factors responsible for overexpression of proinflammatory cytokines. This is demonstrated by increased NF‐κB activity and other dependent immune factors in inflammatory bowel disease (IBD). Anti‐inflammatory effects of silibinin and ursodeoxycholic acid (UDCA) along with their NF‐κB inhibitory property are thought to be beneficial in colitis. Trinitrobenzene sulfonic acid was used to induce colitis rat models. After instillation, 48 rats were treated with oral silibinin, UDCA alone or a combination of both. Intraperitoneal dexamethasone was used in the control group. After 12 days of treatment, colonic samples were tested for the severity of mucosal damage macroscopically and microscopically. The levels of activated NF‐κB, IL‐1β, TNF‐α, myeloperoxidase, thiobarbituric acid reactive substances (TBARS), protein carbonyl, and the antioxidant power of the bowel homogenates were determined. The results indicated a significant reduction in NF‐κB activity as well as the levels of IL‐1β, TNF‐α, TBARS, protein carbonyl, myeloperoxidase activity, and an improvement in antioxidant power of colitis in treated rats. Combination therapy resulted in a more prominent improvement in bowel antioxidant power and myeloperoxidase activity. In conclusion, combination of silibinin and UDCA by inhibition of NF‐κB and other relevant inflammatory factors of colitis is a good candidate for management of Crohn’s disease.     

Protective effect of melatonin on myenteric neuron damage in experimental colitis in rats

Inflammation of the colon in patients with ulcerative colitis (UC) causes pain and altered motility, at least in part through the damage of the myenteric neurons (MNs). Thus, it is important to evaluate new drugs for UC treatment that could also protect myenteric neurons efficiently. As a well‐known neural protective and anti‐inflammatory agent, melatonin could protect neurons from damage through the activation of the nuclear factor erythroid 2‐related factor 2 and antioxidant responsive element (Nrf2–ARE) signaling pathway. Therefore, we investigated the potential protective effect of melatonin against MN damage during colitis induced by 2,4‐dinitrobenzene sulfonic acid (DNBS) in rats. Colitis was induced by intracolonic (i.c.) instillation of DNBS and treated with melatonin at a dose of 2.5 mg/kg for 4 days. The damage of MN in the left colon was immunohistochemically evaluated in different groups. Ulcerations and inflammation in the colon were semiquantitatively observed. Myeloperoxidase (MPO), superoxide dismutase (SOD), and malondialdehyde (MDA) levels were detected to evaluate the inflammatory and oxidative stress status. The protein and mRNA expressions of Nrf2 and heme oxygenase‐1 (HO‐1) in the colon were detected by Western blot and quantitative polymerase chain reaction (qPCR), respectively. Melatonin partially prevented the loss of MN and alleviated the inflammation and oxidative stress induced by DNBS. In addition, melatonin markedly increased the Nrf2 and HO‐1 level in the colitis. These results indicate that melatonin protects MN from damage by reducing inflammation and oxidative stress, effects that are partly mediated by the Nrf2–ARE pathway.     

免疫复合物IgG及补体C_(3c)在溃疡性结肠炎免疫发病机制中的作用

目的揭示溃疡性结肠炎免疫学发病新观点。方法检测 5 0例溃疡性结肠炎结肠粘膜活检标本 (32例活动期 ,18例非活动期 )及5例对照组的免疫复合物 Ig G与补体 C3c。结果免疫复合物及补体同时在粘膜上皮下及小血管壁基底膜沉积 ,在活动期较非活动期明显增强。结论免疫复合物和补体的活化与溃疡性结肠炎的活动性密切相关 ,为溃疡性结肠炎活动期组织损伤的重要参与者 ,并已成为溃疡性结肠炎免疫调节网络中的组成成分     

Potential of levocetirizine in the relief of nasal congestion

Nasal congestion is a common and troublesome symptom of allergic rhinitis. Because it impairs the natural human drive for nasal breathing, it -- in addition -- leads to lower self-esteem and to impaired quality of life. It is a symptom that is difficult to treat. Traditionally, intranasal steroids, because of their potent anti-inflammatory properties, and vasoconstrictors have been utilized for relieving the nasal passages from the inflamed and congested mucosal tissues. Recent studies with the last-generation antihistamines have demonstrated the decongestant properties of these antihistamines in both the more acute seasonal allergic rhinitis and the more chronic and lasting perennial allergic rhinitis. This study aims to review the efficacy of the potent antihistamine, levocetirizine, in relieving nasal congestion as reported in various studies and settings. Comparisons with placebo and with other antihistamines have been presented in order to help general medical practitioners differentiate between the properties of the various available antihistamines.     

Increased serum concentrations and surface expression on peripheral white blood cells of decay-accelerating factor (CD55) in patients with active ulcerative colitis

Inflammatory stimuli induce expression and release of decay-accelerating factor (DAF), a complement-regulatory protein present on peripheral-blood cells. Therefore, in ulcerative colitis (UC), an inflammatory colonic disease in which activated leukocytes are involved, DAF may be released from leukocytes into the circulation. In this study we compared serum DAF concentrations and surface DAF expression on peripheral-blood cells in patients with UC with disease activity. Peripheral-blood samples were obtained from 60 patients with UC (30 with active and 30 with inactive disease) and 19 healthy volunteers. Serum DAF concentrations were determined by means of immunoassay, and surface DAF expression on blood cells was examined with the use of flow cytometry. Serum DAF concentrations in patients with active disease (mean 48.6 ng/mL) were significantly higher than those in patients whose disease was in remission (33.3 ng/mL; P =.0003) and those in healthy controls (32.3 ng/mL; P =.0007). Surface DAF expression on neutrophils, CD14+ monocytes, and subsets of lymphocytes in patients with active UC was significantly increased compared with that in patients with UC in remission and in healthy controls. The increased serum DAF concentrations and surface DAF expression on leukocyte fractions in patients with active disease fell to significantly lower levels when the disease had gone into remission after medical therapy. Serum DAF concentrations are increased in UC patients in relation to disease activity. The likely source of increased DAF concentrations is peripheral-blood leukocytes that have been activated as part of the UC disease process.     

Gastroprotective effect of esculin on ethanol‐induced gastric lesion in mice

The gastroprotective effect of esculin was investigated in a mouse model of ethanol‐induced gastric lesion. Administration of esculin at doses of 5, 10, and 20 mg/kg body weight prior to ethanol ingestion led to significant gastroprotection compared with untreated mice. Gastric mucosal lesions were evaluated by macroscopic and histopathological alterations, lesion index, and myeloperoxidase (MPO) activity. Pretreatment with esculin significantly reduced macroscopic and histopathological damage, gastric lesion index, and MPO activity in a dose‐dependent manner. Moreover, esculin significantly reduced nitric oxide (NO) production, inducible NO synthase (iNOS) levels, and nuclear factor‐kappa B (NF‐κB) p65 protein expression in gastric tissues after ethanol challenge. Analysis of inflammatory cytokines indicated that esculin pretreatment markedly suppressed the increased expression of tumor necrosis factor‐alpha (TNF‐α) and interleukin‐6 (IL‐6) in ethanol‐treated mice. The results demonstrate a protective effect of esculin against gastric injury and suggest that the underlying mechanism might be associated with inhibition of NF‐κB activation, which subsequently reduces expression of iNOS, TNF‐α, and IL‐6.     

Silencing of Apis mellifera dorsal genes reveals their role in expression of the antimicrobial peptide defensin‐1

Like all other insects, two key signalling pathways [Toll and immune deficiency (Imd)] regulate the induction of honey bee immune effectors that target microbial pathogens. Amongst these effectors are antimicrobial peptides (AMPs) that are presumed to be produced by the nuclear factors kappa B (NF‐κB) Dorsal and Relish from the Toll and Imd pathways, respectively. Using in silico analysis, we previously proposed that the honey bee AMP defensin‐1 was regulated by the Toll pathway, whereas hymenoptaecin was regulated by Imd and abaecin by both the Toll and Imd pathways. Here we use an RNA interference (RNAi) assay to determine the role of Dorsal in regulating abaecin and defensin‐1. Honey bees have two dorsal genes (dorsal‐1 and dorsal‐2) and two splicing isoforms of dorsal‐1 (dorsal‐1A and dorsal‐1B). Accordingly, we used both single and multiple (double or triple) isoform knockdown strategies to clarify the roles of dorsal proteins and their isoforms. Down‐regulation of defensin‐1 was observed for dorsal‐1A and dorsal‐2 knockdowns, but abaecin expression was not affected by dorsal RNAi. We conclude that defensin‐1 is regulated by Dorsal (Toll pathway).     

Anti‐inflammatory effect of 4‐methylcyclopentadecanone in rats submitted to ischemic stroke

This study aimed to investigate the anti‐inflammatory effect of 4‐methylcyclopentadecanone (4‐MCPC) in rats suffering from a cerebral ischemia/reperfusion (I/R) injury. In this study, the focal cerebral ischemia in rats was induced by middle cerebral artery occlusion (MCAO) for 2 h, and the rats were treated with 4‐MCPC (8 mg/kg) just 0.5 h before reperfusion. The ischemic infarct volume was recorded 24 h after the MCAO. In addition, myeloperoxidase (MPO) activity and TNF‐α and IL‐1β levels in the ischemic cerebral cortex were determined by ELISA, while nuclear translocation of NF‐κB p65 subunit and expression of p‐IκBα were investigated by Western blotting. Our results showed that 4‐MCPC treatment decreased infarct volume significantly, compared with I/R group (16.8%±7.5% vs. 39.7%±10.9%); it reduced MPO activity (0.43 ± 0.10 vs. 1.00 ± 0.51 U/g) and expression levels of TNF‐α (18.90 ± 3.65 vs. 35.87 ± 4.87 ng/g) and IL‐1β (1.68 ± 0.23 vs. 2.67 ± 0.38 ng/g) in ischemic brain tissues of rats. Further study revealed that 4‐MCPC treatment markedly reduced nuclear translocation of NF‐κB p65 subunit and expression of p‐IκBα in ischemic cerebral cortex. Taken together, our results suggest that 4‐MCPC protects against cerebral I/R injury and displays anti‐inflammatory actions through inhibition of the NF‐κB signal pathway.     

Osteoprotegerin,a new actor in vasculogenesis,stimulates endothelial colony‐forming cells properties

Summary. Background: Osteoprotegerin (OPG), a soluble receptor of the tumour necrosis factor family, and its ligand, the receptor activator of nuclear factor‐κB ligand (RANKL), are emerging as important regulators of vascular pathophysiology. Objectives: We evaluated their effects on vasculogenesis induced by endothelial colony‐forming cells (ECFC) and on neovessel formation in vivo. Methods: Effects of OPG and RANKL on in vitro angiogenesis were evaluated after ECFC incubation with OPG or RANKL (0–50 ng mL^?1). Effects on microvessel formation were evaluated with an in vivo murin Matrigel plug assay. Vascularization was evaluated by measuring plug hemoglobin and vascular endothelial growth factor (VEGF)‐R2 content 14 days after implantation. Results: We found that ECFC expressed OPG and RANK but not RANKL mRNA. Treatment of ECFC with VEGF or stromal cell‐derived factor‐1 (SDF‐1) upregulated OPG mRNA expression. OPG stimulated ECFC migration (P < 0.05), chemotaxis (P < 0.05) and vascular cord formation on Matrigel^® (P < 0.01). These effects were correlated with SDF‐1 mRNA overexpression, which was 30‐fold higher after 4 h of OPG stimulation (P < 0.01). OPG‐mediated angiogenesis involved the MAPK signaling pathway as well as Akt or mTOR cascades. RANKL also showed pro‐vasculogenic effects in vitro. OPG combined with FGF‐2 promoted neovessel formation in vivo, whereas RANKL had no effect. Conclusions: OPG induces ECFC activation and is a positive regulator of microvessel formation in vivo. Our results suggest that the OPG/RANK/RANKL axis may be involved in vasculogenesis and strongly support a modulatory role in tissue revascularization.     

Myeloid differentiation 2 as a therapeutic target of inflammatory disorders

Lipopolysaccharide (LPS), an endotoxin of Gram-negative bacteria, activates the innate immunity system through a receptor complex of myeloid differentiation 2 (MD-2) and toll-like receptor 4 (TLR4). MD-2 directly recognizes the lipid A domain of LPS, which triggers MD-2/TLR4-mediated cellular response aimed at eliminating the invaded pathogen. However, excess production of inflammatory mediators is harmful to host tissue and this can cause septic death in extreme cases. MD-2 represents an attractive therapeutic target of inflammatory and immune diseases in human. In particular, eritoran is a synthetic tetraacylated lipid A that binds directly to MD-2 and antagonizes LPS binding to the same site, and it ameliorates various inflammatory conditions due to infection or sterile organ injury. In this review, we outline the recent advances in the structure biology of ligand interaction with MD-2/TLR4, and highlight the MD-2-directed LPS antagonists, which are natural and synthetic chemicals, under development to treat inflammatory diseases.