阿魏酸抗LPS诱导的奶牛子宫内膜上皮细胞炎性作用

[目的]为了探明阿魏酸的抗炎机制.[方法]采用组织块培养法获得奶牛子宫内膜上皮细胞.用噻唑蓝(MTT法)检测细胞活力.采用荧光定量PCR方法,分别对对照组、模型组、药物作用高、中、低剂量组在LPS作用3h、6h炎症基因IL-1β、IL-6、IL-8和TNF-α的mRNA变化进行检测.[结果]阿魏酸在一定浓度范围内对细胞增殖无显著影响.药物预处理细胞能够显著降低LPS诱导的IL-1β、IL-6、IL-8和TNF-α的mRNA表达.[结论]阿魏酸能够显著降低LPS刺激细胞后炎症细胞因子的表达,说明阿魏酸是通过抑制炎症因子的表达发挥其抗炎作用.     

荔蒲煎液对脂多糖诱导的大鼠乳腺炎的防治作用

本试验利用脂多糖（LPS）诱发试验性大鼠乳腺炎，探讨中药荔蒲煎液对试验性乳腺炎的防治作用。24只SD孕鼠随机分成阴性对照纽（NC）、阳性对照组（PC）、药物预防纽（Pre）和治疗纽（Tre）。Pre组大鼠灌服荔蒲煎液，持续4d。随后，PC组和Pre组大鼠乳房注入LPS，NC组乳管注入等量生理盐水；Tre组大鼠乳管注入LPS24h后灌服荔蒲煎液，连续灌胃4d。对所有大鼠乳腺组织切片进行组织病理学观察、测定胸腺指数和脾脏指数，并进行白细胞计数以及碱性磷酸酶（ALP）和谷胱甘肽过氧化物酶（GSH—Px）的活性检测。结果表明，Pre和Tre组胸腺、脾脏指数以及GSH-Px活性均明显高于PC组（P〈0．05），而白细胞数与ALP活性则低于PC组，Pre和Tre组之间无明显差异。病理组织学检查显示荔蒲煎液能减轻LPS引起的炎症反应。上述结果提示荔蒲煎液有利于维持机体的氧化-还原平衡，对LPS诱发的试验性大鼠乳腺炎有较好的防治效果。     

The central role of corticotropin-releasing hormone in stress-induced hyperthermia and LPS-induced fever in rats

AIM:To further investigate the role of central corticotropin-releasing hormone in stress-induced hyperthermia and lipopolysaccharide (LPS)-induced fever in the rat.METHODS:Test substances were administered intracerebroventricularly (icv) via a third ventricle cannula. Body temperature responses were monitored at 30 min intervals using colonic thermistor probes. Arginine vasopressin (AVP) level in the ventral septal area (VSA) determined by radioimmunoassay. RESULTS:In normal saline controls,rats were handled to take the colonic temperature,their body temperature significantly increased with a peak of(0.88±0.31)℃.The injection(icv)of α-helical CRH(9-41),a CRH-41 receptor antagonists,markedly attenuated the stress-induced hyperthermia within 90 min after injection of normal saline.LPS(300 ng,icv)stimulated a biphasic rise in the colonic temperature,the 3.5 h thermal response index(TRI_3.5)and AVP levels in the VSA of LPS-treated rats were higher than those of control rats.The AVP responses to LPS were inhibited significantly by blockade of central CRH actions using α-helical CRH(9-41)(5μg,icv)administered 10 min prior to LPS,whileα-helical CRH(9-41)(5μg,icv)resulted in exacerbated febrile responses to LPS(300 ng,icv). CONCLUSION:Central CRH plays an important role in stress-induced hyperthermia. The injection (icv) of α-helical CRH(9-41) enhances markedly LPS-induced fever in rats. CRH is a dual action molecule in LPS-induced fever, which itself mediates LPS-induced fever, at the same time, and limits the rise in body temperature during fever through actions of AVP in the VSA and glucocoticoids.     

病原性大肠杆菌人工感染鸡外膜蛋白抗体和脂多糖抗体的测定

以提纯的外膜蛋白（Ｏuter membuane puoteins,ＯＭＰs）作包被抗原,应用酶联免疫吸附试验（Ｅnzyme-linked immunosorbant assay,ＥＬＩＳＡ）,测定了禽病原性大肠杆菌Ｏ １８－５６６、Ｏ７８－１６６分离株人工感染鸡的ＯＭＰs抗体。上述分离株２次攻毒鸡的ＯＭＰs抗体高峰期在攻毒后的３～５周;同时,我们以间接血凝试验（Ｉndirict hemagglutination tist,ＩＨＴ）测定了其脂多糖（Ｌipopolysacchauide,ＬＰＳ）抗体,该抗     

lncRNA-47491、lncRNA-49770和lncRNA-51636在发生炎症反应仔猪肝脏和脾脏中的表达分析

本试验旨在研究脂多糖(LPS)诱导仔猪发生炎症反应时肝脏和脾脏炎性细胞因子和lncRNA-47491、lncRNA-49770、lncRNA-51636表达的变化。选取8头21日龄、体重(7.15±0.42)kg的杜×长×大三元杂交断奶仔猪,随机分为对照组、LPS组,每个处理4个重复,每个重复1头猪。预试14 d后,LPS组和对照组腹腔分别注射100μg/kg体重的LPS、生理盐水,4 h后屠宰并取肝脏和脾脏组织样待测。结果表明:与对照组相比,LPS刺激使肝脏和脾脏中炎性细胞因子的mRNA表达量显著上调;LPS诱导的炎症反应中lncRNA-47491、lncRNA-49770和lncRNA-51636的表达量均显著上调;对lncRNA调控的顺式靶标基因的预测结果显示,lncRNA-47491和lncRNA-51636的靶基因有TMEM235、PGS1、TK1等,lncRNA-49770的靶基因有SRRM2、CLDN6、TNFRSF12A等,且这些基因均与炎症相关。综上,lncRNA-47491、lncRNA-49770及lncRNA-51636可能参与了机体的炎症反应,且靶标基因的预测提示其可能发挥不同的调控作用。     

紫锥菊多糖对LPS损伤后IEC-6细胞的增殖作用

[目的]为了研究紫锥菊多糖对LPS损伤后小肠上皮细胞株IEC-6细胞增殖的影响。[方法]以IEC-6细胞为研究对象,将LPS 10μg/ml分别与EPS 50、100、200、500μg/ml先后加入培养液,采用MTT方法检测细胞增殖率,观察紫锥菊多糖对该细胞增殖的影响。[结果]紫锥菊多糖100、500μg/ml对LPS损伤后的IEC-6细胞分别在48、72 h具有促增殖作用,因此紫锥菊多糖对LPS损伤后的IEC-6细胞具有保护作用。[结论]紫锥菊多糖预处理能增强LPS损伤后IEC-6细胞的增殖活性,能降低LPS对IEC-6细胞的损伤而显现出对细胞的保护作用。     

Berberine hydrochloride attenuates cyclooxygenase-2 expression in rat small intestinal mucosa during acute endotoxemia

The effect of berberine hydrochloride (BBR) on inducible cyclooxygenase-2 (COX-2) in small intestinal mucosa and related mechanisms was investigated in a rat model of acute endotoxemia. The results showed that lipopolysaccharide (LPS) increased COX-2 expression, whereas SB202190 and BBR curtailed it. LPS increased phosphorylation of mucosal p38 MAPK and ATF2 as well as production of ATF2, whereas BBR attenuated these effects. LPS upregulated mucosal peroxisome proliferator-activated receptor gamma (PPARγ), but BBR reduced this receptor. GW9662 aggravated LPS-induced and reversed BBR-attenuated COX-2 expression. The findings showed that BBR ameliorated COX-2 overexpression partially via modulation of p38 and PPARγ pathways during acute endotoxemia.     

Acute phase proteins in naturally occurring respiratory disease of feedlot cattle

The aim of this study was to evaluate three acute phase proteins (APP) [haptoglobin (HPT), lipopolysaccharide binding protein (LBP) and transferrin (Tf)] in feedlot cattle with naturally occurring respiratory disease diagnosed by a calf health scoring chart (CHSC). Seventy-seven beef calves were observed for signs of Bovine Respiratory Disease (BRD) during the first 28 days after arrival at the feedlot. Fourteen cases and pen matched controls were selected based on the CHSC. BRD cases were defined as a score of ≥5, while controls were defined as a score ≤4. The mean CHSC score in cases was 6.9 which was significantly greater than the controls 2.8 (P < 0.01). Mean plasma LBP and HPT concentrations were significantly greater in cases than controls (P < 0.01). Our study results show that measurement of HPT and LBP could be useful in detecting respiratory disease in feedlot conditions. Transferrin concentrations between the two groups were not statistically different.     

Induction of Toll-like receptor 4 signaling in avian macrophages inhibits infectious laryngotracheitis virus replication in a nitric oxide dependent way

LPS is one of the pathogen associated molecular patterns that activates Toll-like receptor 4 (TLR4) signaling pathway eliciting antiviral host responses in mammals although information on such responses in avian species is scarce. Our objectives were to characterize the LPS induced innate responses particularly the expression of LPS receptors (TLR4, CD14) in avian macrophages and observe whether TLR4 mediated induction of NO can elicit antiviral response against infectious laryngotracheitis virus (ILTV) replication. We found that LPS was capable of inducing the expression of TLR4, CD14 and NO production but not the type 1 interferons in an avian macrophage cell line, MQ-NCSU. We also showed that TLR4 mediated NO production can lead to antiviral response against ILTV replication when MQ-NCSU cells were treated with LPS and the resultant supernatant was then transferred to ILTV replicating cells to assess antiviral activity. Antiviral activity of NO was blocked by a selective inhibitor, S-methylisothiourea sulfhate that inhibits inducible NO synthase. This observation confirms that the antiviral activity is positively correlated with NO production. The data show that LPS can be a potential innate immune stimulant that can be used against ILTV infection in chickens that require further evaluation in vivo.     

Non-typhoidal Salmonella encephalopathy involving lipopolysaccharide in cattle

This study assessed the involvement of lipopolysaccharide (LPS) in the non-typhoidal Salmonella encephalopathy (NTSE) caused by a unique isolate of Salmonella enterica serovar Saint-paul (SstpNPG). NTSE was prevented by genetic (deletion of murE) or pharmacologic (polymyxin) disruption of LPS on SstpNPG although the disruption of LPS did not deter brain penetration of the strain. This is the first study to demonstrate that LPS is involved in the manifestations of NTSE.