Suppression of dextran sodium sulfate-induced colitis in mice by zerumbone, a subtropical ginger sesquiterpene, and nimesulide: separately and in combination

Ulcerative colitis (UC) and Crohn's disease are inflammatory disorders of unknown cause and difficult to treat, though some synthetic chemicals, including ligands for peroxisome proliferator-activated receptors (PPARs), are anticipated to be useful drugs. In contrast, few food phytochemicals have been reported to suppress colitis in animal models. The present study was undertaken to explore the suppressive efficacy of zerumbone (ZER), a sesquiterpenoid present in the rhizome of Zingiber zerumbet Smith that is used as a condiment in Southeast Asian countries and known to be a potent suppressant of cyclooxygenase (COX)-2 and inducible nitric oxide synthase expression in cell culture systems. Acute colitis was induced by exposing female ICR mice to 5% DSS in drinking water for 1 week. One week prior to DSS administration, the experimental mice were fed ZER alone, nimesulide (NIM, a selective COX-2 inhibitor) alone, or both in combination (1000 ppm each) for a total of 2 weeks. Inflammatory biomarkers, i.e. interleukin (IL)-1alpha and IL-1beta, tumor necrosis factor (TNF)-alpha, and prostaglandin (PG)E(2) and PGF(2alpha) in colonic mucosa were quantified by an enzyme-linked immunosorbent assay in conjunction with histological alterations. Oral feeding of ZER significantly lowered the levels of IL-1beta [inhibitory rate (IR)=34%], TNF-alpha (IR=29%), and PGE(2) (IR=73%) and suppressed DSS-induced colitis, whereas NIM suppressed the histological changes induced by DSS without affecting inflammatory biomarkers. However, their treatment in combination was most effective for suppressing these biomarkers. Our results suggest that ZER is a novel food factor for mitigating experimental UC and that use of a combination of agents, with different modes of actions, may be an effective anti-inflammatory strategy.     

Susceptibility to ovalbumin-induced airway inflammation and fibrosis in inducible nitric oxide synthetase-deficient mice: mechanisms and consequences

In a previous study, we showed that BALB/c mice demonstrate significant increases in accumulation of airway collagen after 4 weeks of exposure to ovalbumin aerosol. In the current study we examined the response to ovalbumin aerosol of a different strain of mice, C57BL/6, and compared this response to an otherwise isogenic C57BL strain (iNOS(-/-)) in which the gene for inducible nitric oxide synthetase (iNOS) had been knocked out. We hypothesized that C57BL mice, a Th-1-responsive strain, would be relatively resistant to ovalbumin exposure compared with our previous observations in the BALB/c strain, a Th-2 responder. Our results are consistent with this hypothesis, especially with respect to the accumulation of collagen in the airways of the mice exposed to ovalbumin and increased airway reactivity to challenge with methacholine, as measured by the Penh response. Since NO participates in multiple signal transduction pathways, there was no a priori reason to predict whether iNOS(-/-) mice would be more or less susceptible to allergen-induced airway inflammation than their parental wild-type strain. Responses to ovalbumin exposure of the Th-1-responsive C57BL animals were significantly less (or slower) than those we observed with the iNOS(-/-) mice. Significant increases in airway collagen content were seen only after 6 weeks of exposure of the C57BL mice, as contrasted with 4 weeks in the iNOS(-/-) animals. At each time point examined, Penh values for the iNOS(-/-) mice were significantly increased, while no increases were observed with the C57BL strain. Thus, the iNOS(-/-) mice are more susceptible to ovalbumin-induced airway inflammation and fibrosis than the C57BL strain, giving results intermediate between the previous observations in BALB/c mice and our current findings in C57BL animals with the various assays performed. We also asked whether the effects of knocking out the iNOS gene were exerted before or after the release of TGF-beta(1) by eosinophils and other effector cells in the lung. We measured the response of C57BL and iNOS(-/-) mice to direct intratracheal challenge with TGF-beta(1). There was no apparent response of C57BL mice to TGF-beta(1) at 4 or 11 days after TGF-beta(1) challenge, as evaluated by bronchoprovocation testing. On the other hand, the observed Penh values were significantly greater in iNOS(-/-) mice that had also received TGF-beta(1) 4 days previously. These results strongly support the hypothesis that the increased sensitivity of iNOS(-/-) mice to ovalbumin is at least partially dependent on pathways that come into play subsequent to the release of TGF-beta(1) by effector cells in the lungs of mice exposed to ovalbumin aerosol.     

Acetylcholinesterase induces the expression of the beta-amyloid precursor protein in glia and activates glial cells in culture

Acetylcholinesterase (AChE) activities in CNS physiopathology are increasingly diverse and range from neuritogenesis, through synaptogenesis, to enhancement of amyloid fiber assembly. In Alzheimer's disease, senile plaques and neurodegeneration specially affect regions enriched for cholinergic synapses. In this study we show an effect of AChE that could contribute to the increased deposition of Abeta in certain regions. Affinity-purified AChE induced the expression of amyloid-beta-precursor protein (beta-APP) in glial cells in a concentration-dependent manner up to 5 nM. In glia, AChE also increased inducible nitric oxide synthase (iNOS) assessed by immunocytochemistry and decreased reductive metabolism as evidence of cell activation. AChE could increase the expression of beta-APP in astrocytes and microglia as result of the activation of glial cells. As a whole, we found that AChE has additional effects that could result in an increased synthesis of Abeta, both by increasing beta-APP expression of astrocytes and by further activating glial cells.     

P38MAPK/iNOS信号通路对肾脏缺血预处理的延迟保护效应

目的 探讨P38MAPK与iNOS在肾脏缺血预处理时两者的上下游关系,旨在阐明肾脏缺血预处理延迟保护的可能机制. 方法 雄性Wistar大鼠60只,随机分为五组,每组12只大鼠,分别为:假手术(sham)组,缺血再灌注(IR)组,缺血预处理 缺血再灌注(IPC)组,SB203580药物干预(SB203580)组,氨基胍(AG)药物干预组,各组按再灌注24 h,48 h两时间点又分为两亚组,每组6只大鼠.用苦味酸法测定血清肌酐来反映肾功能变化情况;用HE法观察肾组织形态;用Western blot法检测肾组织P38MAPK与iNOS蛋白的表达,并用图像分析仪进行半定量分析. 结果 血肌酐在IPC组较IR组低(P＜0.05),尤在IPC后48 h明显(P＜0.01);P38MAPK与iNOS表达在sham组,IR组,IPC组三组之间比较有统计学差异,尤在IPC组表达明显(P＜0.01);在SB203580组无P38MAPK蛋白的表达,iNOS的表达较IPC组低(P＜0.05);在AG组无iNOS蛋白表达,P38MAPK蛋白表达与IPC组相差不明显(P＞0.05). 结论 P38MAPK作为iNOS的上游物质参与了肾脏缺血预处理的部分延迟保护效应.     

安神补脑液对睡眠剥夺大鼠脑内诱导型一氧化氮合酶及褪黑素的影响

目的研究安神补脑液对睡眠剥夺大鼠脑内诱导型一氧化氮合酶(iNOS)及褪黑素的影响。方法SD大鼠随机分成正常对照组,模型组,安神补脑液高、低剂量组。灌胃给予安神补脑液2周后,用多站台水环境法复制睡眠剥夺模型,取前脑组织测定iNOS的活性,并用高效液相色谱法测定脑内褪黑素的含量。结果与正常对照组比较,睡眠剥夺大鼠脑组织iNOS活力显著增高,褪黑素有减少的趋势。大剂量安神补脑液可使模型大鼠iNOS活力明显降低(P<0.05),褪黑素含量显著提高(P<0.05)。结论安神补脑液可拮抗睡眠剥夺大鼠脑内iNOS活力提高,并能增高松果体褪黑素的含量,提示安神补脑液可以改善睡眠障碍导致的脑功能改变。     

颈交感神经干离断对局灶性脑缺血再灌注后大鼠海马iNOS表达的影响

目的采用颈交感干离断（TCST）模拟星状神经节阻滞，观察其对局灶性脑缺血再灌注损伤（CIRI）大鼠脑梗死容积及海马诱导型一氧化氮合酶（iNOS）表达等的影响，并探讨其脑保护作用的机制。方法将大鼠随机分成实验组（A组）、对照组（B组）和假手术组（C组）；采用线栓法行大脑中动脉栓塞（MCAO）制作大鼠局灶性CIRI模型，A组于TCST后即行MCAO，2h后再恢复灌注；B组为单纯CIRI组；C组仅完成与A组相似的手术步骤但不造成MCAO、不行TCST；再灌注24h后观察各组大鼠神经行为学评分、脑梗死容积及海马iNOs的表达变化。结果A组大鼠脑梗死容积和神经行为学评分均低于B组（P〈0．05）；与A组、C组相比，B组大鼠海马iNOS的表达增加（P〈0．05），而A组与C组间无显著差异（P〉0．05）。结论TCST可通过下调大鼠海马iNOS的表达而对局灶性CIRI发挥脑保护作用。     

严重创伤早期大鼠下丘脑HSP70与iNOS表达与分布的时效关系

目的研究严重创伤早期大鼠下丘脑热休克蛋白(HSP)70与诱导型一氧化氮合酶(iNOS)转录表达变化分布和意义.方法采用BIM-Ⅲ型生物撞击机致大鼠胸部严重撞击伤,并造成单侧股骨骨折,运用S-ABC免疫组化、原位杂交技术测定下丘脑HSP70与iNOS及其mRNA的转录表达水平.结果正常对照组HSP70低水平表达,在伤后1小时即开始明显增高(P＜0.05),6小时达到峰值为正常的18倍,12小时后开始下降,24小时时主要集中在室旁核内;iNOS无基础表达,在伤后1小时开始出现,随HSP70同步增高,8小时达到高峰,较1小时时增加13倍.两者相关系数r=0.97601.结论严重创伤后早期下丘脑内HSP70和iNOS过度表达, 在严重创伤应激时下丘脑的损伤与抗损伤机制中起重要作用.     

Effect of a Korean Traditional Formulation, Hwaotang, on Superoxide Generation in Human Neutrophils, Platelet Aggregation in Human Blood, and Nitric Oxide, Prostaglandin E2 Production and Paw Oedema Induced by Carrageenan in Mice

Hwaotang, a traditional Korean medicinal formulation, is a dried decoctum of a mixture of 7 herbal medicines, consisting of Angelica gigantis Radix, Rehmanniae radix, Paeoniae radix, Ciniamomi cortex, Cnidii rhizoma, Persicae semen and Carthami flos. We have investigated that Hwaotang water extract (HOT) has various effects on stimulus-induced superoxide generation in human neutrophils. The effects of HOT on superoxide generation in human neutrophils were investigated. HOT significantly inhibited N-formyl-methionyl-leucyl-phenylalanine (fMLP)-induced superoxide generation in a concentration-dependent manner, but not that induced by arachidonic acid (AA). On the other hand, HOT enhanced superoxide generation induced by phorbol 12-myristate 13-acetate (PMA) in a concentration-dependent manner. The superoxide generation induced by PMA with HOT was suppressed by staurosporine, an inhibitor of protein kinase C, but was not suppressed by genistein, an inhibitor of protein tyrosine kinase. Tyrosyl phosphorylation of a 58 kDa protein, which was increased by fMLP, was inhibited by HOT. HOT also inhibited the generation of a 47 kDa protein and platelet aggregation in human blood. The results suggest that protein tyrosine kinase participates in fMLP-mediated superoxide generation by HOT-treated human neutrophils. HOT inhibited neutrophil functions, including degranulation, superoxide generation, and leukotriene B4 production, without any effect on 5-lipoxygenase activity. HOT reduced nitric oxide (NO) and prostaglandin E2 production in mouse peritoneal macrophages stimulated with lipopolysaccharide, whereas no influence on the activity of iNOS, COX-2 or COX-1 was observed. HOT significantly reduced mouse paw oedema induced by carrageenan. Western blot analysis showed that HOT reduced the expression of iNOS and COX-2. The results indicate that HOT exerts anti-inflammatory effects related to the inhibition of neutrophil functions and of NO and prostaglandin E2 production, which could be due to a decreased expression of iNOS and COX-2.     

抑癌基因PTEN与iNOS在胶质瘤中表达及意义

目的探讨抑癌基因PTEN和诱导型一氧化氮合酶(iNOS)在胶质瘤组织中表达意义及两者与胶质瘤侵袭性的关系。方法采用LSAB免疫组织化学法检测56例胶质瘤中PTEN、iNOS蛋白的表达,并分析两者与胶质瘤病理级别和侵袭性的关系。结果PTEN在胶质瘤Ⅰ、Ⅱ、Ⅲ、Ⅳ级中阳性率分别为91．7％、75％、53．3％、15．4％,PTEN表达阳性率随病理分级升高而降低(P＜0．01)。而iNOS表达阳性率分别为50％、38．1％、73．3％、76．9％;iNOS表达水平与PTEN表达水平呈负相关(P＜0．05)。结论PTEN和iNOS的表达一定程度反映胶质瘤的恶性度和侵袭性强弱;PTEN缺失可引起iNOS表达增加,在胶质瘤发生、发展过程中发挥重要作用。     

A functional variant of the iNOS gene flanking region is associated with LAD coronary artery disease: an autopsy study

Background Recent studies using reporter gene constructs have indicated significant differences in the promoter activity of inducible nitric oxide synthase (iNOS) gene variants. Although the exact role of iNOS in atherogenesis is unclear, it is possible that this variation site may influence the extent of coronary artery disease (CAD). Methods We amplified these (AAAT) repeat variants from the NOS2A gene (denoted iNOS R4 and iNOS R5) from 325 Finnish men included in the Helsinki Sudden Death Study, and studied their association with indices of stenosis and atherosclerosis of the left anterior descending artery (LAD), right coronary artery (RCA) and left circumflex artery (LCX). In order to understand the effect of iNOS genotype on different stages of CAD, our study population was divided into age groups. Results In the LAD, the progression of atherosclerosis seemed to be more pronounced in the 4/5 genotype carriers than in those with the 4/4 genotype when the different age groups were compared. More specifically, statistically significant differences between the genotypes were found in the subgroup of men aged > 55 years. In this group, men carrying the rare R4/5 genotype presented higher mean values of stenosis percentages (55% vs. 42%, P = 0·008), larger areas of fatty streaks (10·4% vs. 5·9%; P = 0·01) and complicated lesions (3·5% vs. 1·3%; P = 0·001) compared with the R4/4 carriers. No significant association of iNOS genotypes with stenosis and atherosclerosis of RCA and LCX was found. Conclusions It appears unlikely the R4/5 genotype plays a major role in the pathogenesis of CAD, as it was not associated with stenosis and atherosclerosis in RCA and LCX. However this genotype may have some role in more pronounced CAD, as seen in the LAD.