皮质醇导致脓毒症大鼠TNF-α释放增加

目的：探讨皮质醇对脓毒症大鼠ＴＮＦ－α、ＩＬ－６释放的影响及其临床意义。方法：ＳＤ大鼠５８只,分为５组,Ａ、Ｃ组于盲肠结扎穿孔ＣＬＰ后每１２ｈ皮下注射氢化可的松（３０ｍｇ／ｋｇ）,Ｂ、Ｄ组于ＣＬＰ后同时点注等量生理盐水,Ｅ组为对照组。Ａ、Ｂ组于４８ｈ,Ｃ、Ｄ组于２４ｈ处死,测定血及腹水中ＴＮＦ－α、ＩＬ－６含量和血中皮质醇水平。结果：Ａ组死亡３例,余各组无死亡。Ａ组血浆皮质醇和ＴＮＦ含量均显著高于Ｂ、Ｃ、Ｄ、Ｅ组（Ｐ＜００５）。Ａ、Ｂ、Ｃ、Ｄ组腹腔液中ＴＮＦ－α含量显著高于Ｅ组（Ｐ＜００５）。所有大鼠腹腔液中ＴＮＦ－α、ＩＬ－６含量均显著高于血浆（Ｐ＜００５）。结论：脓毒症时,应用皮质醇可使血浆ＴＮＦ－α含量升高,且随作用时间延长ＴＮＦ－α升高愈显著,并伴有动物死亡率增加。但对血浆及腹腔液中ＩＬ－６含量无显著影响。     

葛根素对脓毒症大鼠凝血分子标志物水平的影响

目的：观察脓毒症大鼠血浆凝血分子标志物凝血酶原片段1＋2（F1＋2）、D-二聚体（DD）、凝血酶调节蛋白（TM）和P-选择素（Ps）的变化及葛根素（Puerarin，Pue）对该变化的影响。方法：60只动物随机分为正常对照组、假手术组、脓毒症组和葛根素治疗组，采用盲肠结扎穿孔（CLP）术复制脓毒症模型；分别于CLP后2,8、16小时尾静脉采血，ELISA法检测血浆F1＋2、DD、TM和Ps含量的改变。     

利多卡因对脓毒症大鼠心肌损伤及Nrf2/HO-1通路的影响

目的:探究利多卡因对脓毒症大鼠心肌损伤及核因子E2相关因子2/血红素加氧酶1(Nrf2/HO-1)通路的影响.方法:健康雄性SD大鼠随机分为假手术组、模型组和利多卡因组,每组15只.模型组和利多卡因组采用盲肠结扎穿孔法制备脓毒症大鼠模型,假手术组大鼠仅打开腹腔而不进行盲肠结扎穿孔,造模后利多卡因组大鼠给予利多卡因10 ...     

眼镜蛇毒因子抑制脓毒症大鼠的炎症反应

目的观察补体抑制剂眼镜蛇毒因子（CVF）对脓毒症大鼠血清细胞因子释放的影响及对肺组织的保护作用。方法144只清洁雄性SD大鼠（体重250～300g）随机分为A、B、C3组,每组48只。A组假手术组,B组（脓毒症组）采用盲肠结扎穿孔术（CLP）复制脓毒症大鼠模型,C组（CVF组）在盲肠结扎穿孔术前24h按50μg/kg注射CVF,A和B组给予等量生理盐水。于术后6个时间点分别采用放射免疫分析法和酶联免疫吸附法检测血清TNF-α、IL-6和IL-10水平,肺组织MPO含量及病理学改变。结果B组大鼠脓毒症反应最强,A组表现轻微;B组TNF-α及IL-6水平均明显高于A组（P〈0.05,P〈0.01）;B组除2h点外,肺组织MPO水平显著高于A组（P〈0.05,P〈0.01）;B组肺组织损伤最严重;C组经CVF干预后脓毒症反应及肺组织损伤较B组明显减轻,TNF-α、IL-6及MPO水平均较B组明显下降（P〈0.05,P〈0.01）。结论补体抑制剂CVF可减轻脓毒症大鼠的炎症反应,具有肺保护作用。     

丙酮酸乙脂保护脓毒症后肺损伤及其机制的研究

目的：观察脓毒症对小鼠肺相关酶活性的影响,探讨丙酮酸乙脂（Ethyl Pyruvate,EP）在脓毒症中对受损肺脏的作用。方法：采用盲肠结扎穿孔术制备小鼠脓毒症模型,用分光光度法检测肺组织匀浆液中丙二醛（Malonaldehyde,MDA）、丙酮酸（Pyruvate Acid）、乳酸（Lactic Acid）及总抗氧化能力（total anti-oxidative capacity,TAOC）等4种与自由基合成、代谢相关的酶活性,同时采用放射免疫分析测定血清瘦素（leptin）水平。结果：腹腔内注射EP后,肺组织丙二醛、丙酮酸、乳酸及总抗氧化能力等酶活性有不同程度的改变,但结果并非完全抑制或促进。血清leptin水平在EP保护后6h和12h较损伤组各相应时间点显著升高。结论：EP可能通过leptin发挥对脓毒症后受损肺脏的保护作用。     

杀菌性通透性增强蛋白对大肠杆菌脓毒症小鼠的保护作用

本文观察了ＢＰＩ对大肠杆菌脓毒症小鼠预后的影响及其可能机制。研究结果显示〉ＢＰＩ治疗组动物７２小时存活率明显高于生理盐水对照组；注菌后０．５，１ｈ，ＢＰＩ组血清内毒素水平明显低于生理盐水对照组；注菌后１．５ｈ，ＢＰＩ组血清ＴＮＦα峰值也明显低于ＮＳ对照组；但两组间血液细菌计数在注菌后０．５，１．５和３ｈ均明显差异。     

NLRC4炎症小体介导自噬反应在脓毒症心肌功能障碍小鼠中的作用

背景：研究发现炎症小体及自噬在脓毒症患者的免疫功能中扮演了重要角色。但现阶段研究仅局限于探索脓毒症中某一自噬信号通路的变化特点,对脓毒症心肌功能障碍自噬调控的具体机制尚未阐明。目的：探讨核苷酸结合寡聚化结构域样受体蛋白4(NOD-like receptor family,pyrin domain-containing protein 4,NLRC4)炎症小体与自噬水平在小鼠脓毒症心肌功能障碍中的变化,以期为脓毒症心肌功能障碍的发生机制提供理论依据。方法：昆明雄性小鼠48只,随机分为6组,分别为假手术(6,12,24 h)组和盲肠结扎穿孔(6,12,24 h)组。盲肠结扎穿孔组结扎小鼠盲肠远端1/2,22号针头来回穿刺2次,挤出少许肠内容物;假手术组不结扎穿孔,其余操作与盲肠结扎穿孔术相同。观察小鼠术后一般情况,超声测定小鼠心功能,ELISA法检测肿瘤坏死因子α、肌钙蛋白T质量浓度;苏木精-伊红染色法观察心肌病理变化;透射电镜观察心肌线粒体及自噬体变化;实时荧光定量PCR检测心肌组织NLRC4 mRNA的表达,Western blot检测心肌组织炎症因子、LC3、Beclin-1、NLR...     

腹腔感染脓毒症小鼠外周血淋巴细胞CD30的动态表达

目的:探讨腹腔感染脓毒症的病理过程中Th2细胞的分化情况。方法:盲肠结扎穿孔(CLP)复制腹腔感染脓毒症小鼠模型,在不同时点取外周全血进行三色荧光标记,以流式细胞术对CD4⁺细胞表面CD30分子的表达情况进行分析。结果:不同时点的CLP组其CD30分子的表达有所不同,以术后38h为最高,随后呈现总体下降趋势。结论:在脓毒症腹腔感染小鼠的动物模型中,Th2细胞的分化情况随病程的发展有所不同,可能和疾病的严重程度及预后相关。     

中药解毒化瘀治疗对脓毒症大鼠生存率和血浆内毒素的影响

目的:通过动物模型验证中药解毒化瘀治疗对脓毒症的治疗作用.方法:取雄性Wistar大鼠30只,随机分为2组,每组15只.第一组为治疗组,给于解毒化瘀中药;第二组为不治疗对照组,给与生理盐水.7d后,分别采用盲肠结扎穿刺法复制大鼠脓毒症模型.手术后,第一组继续给药;第二组继续给于生理盐水,观察记录每只大鼠的生存天数;另取...     

重组人粒细胞巨噬细胞集落刺激因子联合抗生素治疗腹腔感染

目的： 探讨在抗生素的基础上应用重组人粒细胞巨噬细胞集落刺激因子(rhGM-CSF)对大鼠腹腔感染预后的影响。方法： 68只雄性Wistar大鼠随机分为： rhGM-CSF+头孢呋辛/甲硝唑组（A组）26只、头孢呋辛/甲硝唑组（B组）27只、生理盐水组（C组）15只。盲肠结扎穿刺法（cecal ligation and puncture,CLP）制造腹腔感染的模型。术后观察体重、摄食量的变化,检测血白细胞计数以及骨髓像,分析术后5 d生存率。结果：与B、C两组比较, A组大鼠术后平均体重降幅较小,摄食量恢复明显,血白细胞计数升高,骨髓像增生极度活跃,术后5 d生存率为61.5%,显著高于B组和C组。结论：rhGM-CSF与头孢呋辛/甲硝唑联合应用可提高盲肠穿孔致腹腔感染大鼠的短期生存率,改善其行为活动。     

The Kupffer cell protects against acute lung injury in a rat peritonitis model: role of IL-10

The possibility that Kupffer cells (KCs) play key beneficial and deleterious roles in multiple organ injury in sepsis has been discussed. The role of KCs in lung injury in a rat peritonitis model was investigated. Specifically, the involvement of interleukin (IL)-10, which has anti-inflammatory effects, was examined. Rats were given saline or gadolinium chloride (GdCl3), a KC toxicant, 24 h before cecal ligation and puncture (CLP). Survival was assessed for 7 days after CLP. The liver, lung, and serum were harvested, and the expression of cytokines was assessed. Macrophages were isolated from each organ after CLP, and the mRNA expression of inflammatory mediators was assessed. GdCl3 treatment increased lung injury and mortality. Plasma endotoxin levels were significantly greater, whereas serum IL-10 levels were lower in the GdCl3 than in the control group after CLP. IL-10 levels were significantly greater in the aorta than the hepatic vein. The mRNA expression of IL-10 was less in KCs from the GdCl3 than the control group. In the liver, the expression of IL-10 increased rapidly and continuously, up to 9 h in the control group, but values were significantly lower in the GdCl3 group. Rabbit anti-rat IL-10 antibodies were injected just after CLP to investigate the effects of immunoneutralization of endogenously produced IL-10. In the antibody-treated group, lung injury and mortality increased compared with animals treated with rabbit immunoglobulin G. Taken together, these results indicate that KCs play a protective role in lung injury in sepsis by production of IL-10.     

Modulation of inflammatory response in sepsis by proteasome inhibition

The Ubiquitin-proteasome system has recently been shown to be involved in the regulation of cytokine expression. We tested the hypothesis of whether the in vivo administration of proteasome inhibitor MG-132 can modulate cytokine response and mortality in sepsis. Sepsis was induced in mice by caecal ligation and puncture (CLP). Animals were divided into four groups: control, CLP, CLP and 1 microg MG-132/g of b.w. intraperitoneally, and CLP and 10 microg MG-132/g of b.w. Plasma levels of interleukin (IL)-1, tumour necrosis factor-alpha (TNF-alpha, IL-6 and IL-10 were determined by ELISA 6 h after the induction of sepsis. CLP induced significant increase in plasma levels of all measured cytokines. MG-132 treatment resulted in lower increase in IL-1, TNF-alpha and IL-10 levels. IL-6 was not significantly affected. A mortality study revealed prolonged survival in MG-132 treated mice. We conclude that MG-132 treatment decreases inflammatory response and prolongs survival in the CLP model of sepsis.     

Effects of aging on mortality, hypothermia, and cytokine induction in mice with endotoxemia or sepsis

Aging is accompanied by an altered stress response that underlies increased susceptibility of the elderly patients to physiological stress such as infection and sepsis. In the present study, we investigated the effects of aging on mortality, hypothermia, and cytokine induction in mouse models of intra-abdominal sepsis and endotoxemia. Systemic inflammation associated with either cecal ligation/puncture (CLP) or injection with bacterial endotoxin, lipopolysaccharide (LPS), resulted in a significantly elevated mortality rate in aged (24 months) compared to young (4 months) mice. The aged mice also showed profound hypothermia during these inflammatory stresses; the severity of hypothermia at the early phase of sepsis or endotoxemia could predict the mortality of individual animals. The stress-mediated induction of interleukin-1beta, interleukin-6, and interleukin-10 (IL-1beta, IL-6, and IL-10) in the circulating blood tended to be higher with aging in both CLP and LPS models, and in particular, the induction of IL-6 was significantly augmented with aging. The serum level of IL-6 showed a strong correlation with degrees of hypothermia. In the heart and lungs, the induction of mRNA for IL-6 and IL-10 was also significantly enhanced with aging. These results clearly demonstrate an age-associated increase in mortality, hypothermia, and induction of IL-6 during endotoxemia and sepsis.     

Pattern of cytokines and pharmacomodulation in sepsis induced by cecal ligation and puncture compared with that induced by endotoxin.

The production of tumor necrosis factor alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and IL-6 and their pharmacomodulation were evaluated in a model of polymicrobial sepsis induced in mice by cecal ligation and puncture (CLP) and were compared with the effects of endotoxin (lipopolysaccharide [LPS]) treatment. LPS levels rose as early as 1 h after CLP and increased further after 2 and 21 h. TNF-alpha was detectable in serum, spleen, liver, and lungs during the first 4 h, with a peak 2 h after CLP. IL-1 beta was measurable in serum after 24 h, and levels increased significantly in spleen and liver 4 and 8 h after CLP. IL-6 levels increased significantly in serum throughout the first 16 h after CLP. These cytokines were detectable after LPS injection, with kinetics similar to those after CLP but at a significantly higher level. To cast more light on the differences between these two animal models of septic shock, we studied the effects of different reference drugs. Pretreatment with dexamethasone (DEX); ibuprofen (IBU), an inhibitor of cyclooxygenase; and NG-nitro-L-arginine, an inhibitor of nitric oxide synthase, significantly reduced survival, while chlorpromazine (CPZ) and TNF did not affect it. Only the antibiotics and pentoxifylline significantly increased survival in mice with CLP. However, CPZ and DEX protected the mice from LPS mortality. On inhibiting TNF-alpha with DEX, CPZ, or pentoxifylline, survival was reduced, unchanged, and increased, respectively, and on increasing TNF-alpha with IBU and TNF, survival was decreased or unchanged, respectively, suggesting that the modulation of this cytokine does not play a significant role in sepsis induced by CLP, unlike treatment with LPS. The negative effects of IBU and N(G)-nitro-L-arginine suggest a protective role by prostaglandins and nitric oxide in sepsis induced by CLP.     

Sildenafil treatment attenuates lung and kidney injury due to overproduction of oxidant activity in a rat model of sepsis: a biochemical and histopathological study

Sepsis is a systemic inflammatory response to infection and a major cause of morbidity and mortality. Sildenafil (SLD) is a selective and potent inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase PDE5. We aimed to investigate the protective effects of sildenafil on caecal ligation and puncture (CLP)-induced sepsis in rats. Four groups of rats were used, each composed of 10 rats: (i) 10 mg/kg SLD-treated CLP group; (ii) 20 mg/kg SLD-treated CLP group; (iii) CLP group; and (iv) sham-operated control group. A CLP polymicrobial sepsis model was applied to the rats. All groups were killed 16 h later, and lung, kidney and blood samples were analysed histopathologically and biochemically. Sildenafil increased glutathione (GSH) and decreased the activation of myeloperoxidase (MPO) and of lipid peroxidase (LPO) and levels of superoxide dismutase (SOD) in the septic rats. We observed a significant decrease in LPO and MPO and a decrease in SOD activity in the sildenafil-treated CLP rats compared with the sham group. In addition, 20 mg/kg sildenafil treatment in the sham-operated rats improved the biochemical status of lungs and kidneys. Histopathological analysis revealed significant differences in inflammation scores between the sepsis group and the other groups, except the CLP + sildenafil 10 mg/kg group. The CLP + sildenafil 20 mg/kg group had the lowest inflammation score. Sildenafil treatment decreased the serum tumour necrosis factor (TNF)-α level when compared to the CLP group. Our results indicate that sildenafil is a highly protective agent in preventing lung and kidney damage caused by CLP-induced sepsis via maintenance of the oxidant-anti-oxidant status and decrease in the level of TNF-α.     

热休克蛋白70对内毒素致门静脉高压性胃病大鼠胃黏膜损伤的保护作用研究

目的: 探讨热休克蛋白70(HSP70)对内毒素诱导的肝硬化门静脉高压性胃病(PHG)大鼠胃黏膜损伤的作用及机制。方法: 以CCl₄制备肝硬化PHG大鼠模型。热处理诱导HSP70表达,注射内毒素及其拮抗剂BPI21,酶联免疫吸附测定(ELISA)检测HSP70和TNF-α水平,HE染色观察胃黏膜病理变化。实验分为正常对照组、PHG组、PHG+热处理组、PHG+内毒素组及PHG＋BPI21组。结果: (1) PHG时胃黏膜HSP70表达明显减少,血浆内毒素及胃黏膜TNF-α表达明显增加,胃黏膜损伤明显;(2) 外源性内毒素增加PHG大鼠胃黏膜TNF-α表达,加重其胃黏膜损伤;BPI21则显著减少其TNF-α表达,减轻胃黏膜损伤;(3)热处理增加PHG大鼠胃黏膜HSP70表达,减少TNF-α表达,减轻胃黏膜损伤。结论: HSP70减轻PHG胃黏膜损伤,其机制可能与降低胃黏膜TNF-α水平有关。     

肉苁蓉对败血症大鼠胸腺细胞的保护作用

目的：探讨肉苁蓉提取物对败血症休克大鼠胸腺细胞凋亡的影响及其可能机制。方法: 盲肠结扎穿孔术（CLP）造成大鼠败血症休克。防治组术前14 d开始给药（1.25 g/kg），分别于术后12 h、24 h取材。流式细胞仪检测细胞凋亡率和线粒体膜电位，分光光度法测定细胞线粒体ATP酶活力。结果 预先给予肉苁蓉提取物的大鼠，行CLP术后12、24 h胸腺细胞凋亡率均低于模型组（P<0.01），线粒体膜电位和ATP酶活力则显著上升（P<0.01）。结论： 肉苁蓉提取物对败血症休克时胸腺细胞有保护作用，其机制可能是提高ATP酶活力，维持了细胞线粒体膜电位。     

Inhibition of endogenous glucocorticoid synthesis aggravates lung injury triggered by septic shock in rats

The aim of this study was to determine the effects of previous administration of metyrapone (met) on the acute lung injury (ALI) induced by caecal ligation and puncture (CLP) and to explore met's relationship with endogenous glucocorticoids (GCs) as measured by inflammatory, oxidative and functional parameters. One hundred and thirty‐five Wistar rats were divided into three main groups: Control (Naïve), Sham and CLP. The animals received pretreatment one hour before surgery. The Naïve group did not undergo any procedure or pretreatment. The Sham group only had the caecum exposed and was pretreated with saline. The CLP group was divided into three pretreatments: metyrapone (CLP met 50 mg/kg i.p.), dexamethasone (CLP dex 0.5 mg/kg i.p.) or saline (CLP sal equivalent volume of 0.9% NaCl). Analyses were performed after 6 and 24 h of sepsis. Previous administration of met significantly increased inflammatory cells, as well as myeloperoxidase (MPO) activity in the lung tissue and alveolar collapsed area, with consequent impairment of respiratory mechanics being observed compared to Sham and Naïve; CLP sal exhibited similar results to those of met. The met reduced corticosterone (CCT) levels and dramatically increased hydrogen peroxide (H₂O₂) levels in the lung tissue compared to CLP sal. Our results suggest that previous administration of met may have contributed to increased pulmonary oxidative stress and increased mortality by mechanisms dependent of endogenous GC.     

LPS pretreatment ameliorates multiple organ injuries and improves survival in a murine model of polymicrobial sepsis

Objective  

The endotoxin tolerance phenotype is characterized with decreased inflammation and increased phagocytosis. We hypothesized that endotoxin tolerance would provide protective effects on experimental sepsis with multiple organ injuries induced by cecal ligation and puncture (CLP).     

An essential role of macrophage inflammatory protein 1alpha/CCL3 on the expression of host's innate immunities against infectious complications

Sepsis was induced by well-controlled cecal ligation and puncture (CLP) in macrophage inflammatory protein 1alpha (MIP-1alpha)/CCL3 knockout (CCL3(-/-)) and severe combined immunodeficiency (SCID) mice. CCL3(-/-) mice and their littermates (CCL3(+/+) mice) treated with anti-CCL3 monoclonal antibodies were susceptible (0-20% survival) to CLP-induced sepsis, and CCL3(-/-) mice supplemented with recombinant (r)CCL3 (250 ng/mouse) and CCL3(+/+) mice were resistant (70-80% survival). The resistance of SCID mice to CLP was markedly improved by the rCCL3 administration (88% survival), and SCID mice treated with saline were shown to be middling resistant to the same CLP (45% survival). However, the resistance of SCID-M mice (SCID mice depleted of the macrophage function) to CLP was not improved by the rCCL3 administration (11% survival), and 41% of SCID-M mice reconstituted with normal peritoneal macrophages and 79% of SCID-M mice inoculated with CCL3-treated peritoneal macrophages survived. In addition, the resistance of SCID-MN mice (SCID mice depleted of functional macrophages and neutrophils) to CLP was improved by the inoculation of CCL3-treated macrophages (78% survival), and all of SCID-MN mice inoculated with CCL3-treated neutrophils died. CCL3 is shown to be essential to the host resistance against bacterial sepsis. Macrophages but not neutrophils are highlighted as the major effector cells when protective innate immunities against sepsis are improved by CCL3.