体外细胞炎性损伤模型的建立

目的体外复制细胞炎性损伤模型用于体外炎症研究。方法将人脐静脉内皮细胞(HUVEC)培养后分组,用不同浓度(0、0.1、1、10、20μg/ml)的脂多糖(LPS)刺激,在不同时间点(4、12、24、48h)收样品,检测细胞上清中的白介素-6(IL-6)水平。结果每个时间点的HUVEC:LPS(0.1、1、10、20μg/ml)比LPS(0μg/ml)刺激后IL-6分泌明显增高(P<0.05);48h内随时间增加,IL-6分泌增加,呈线性关系;相同时间点不同LPS浓度(0.1、1、10、20μg/ml)刺激细胞产生的IL-6分泌差异无统计学意义(P>0.05)。结论体外LPS刺激HUVEC是理想的细胞炎性损伤模型。

腺苷A2B受体活化对TNF-α致人肺微血管内皮细胞炎性损伤的影响

目的探讨腺苷A2B受体（A2BR）在肿瘤坏死因子-α（TNF-α）诱导肺微血管内皮炎性损伤中的作用及机制。方法体外培养人肺微血管内皮细胞（HPMECs），分别进行TNF-α剂量-时效实验和A2BR靶向激动剂／抑制剂干预实验。①剂量一时效实验：先将细胞分为5组，分别加入终浓度为0（空白对照）、20、50、100、150μg/L的TNF-α孵育24h，选最佳刺激浓度；另取细胞分为6组，以终浓度100μg／LTNF—α分别培养HPMECs0、4、8、12、24、36h，确定最佳作用时间。检测各组细胞A2BmRNA和蛋白表达情况。②A2BR的靶向激动剂／抑制剂干预实验：将细胞分为1μmol／LA2BR靶向激动剂BAY60—6583＋100LTNF—α组（B＋T组）、μmol／LA2BR靶向抑制剂PSBlll5＋100删LTNF-α组（P＋T组）和TNF-α、BAY60—6583、PSBlll5单独刺激组以及空白对照组。检测各组细胞活性、细胞周期以及血管内皮细胞黏附分子-1（VCAM-1）、白细胞介素-1p（IL-1p）的蛋白表达水平。结果①剂量一时效实验：将空白对照组的值设为1，随着TNF—α浓度的升高，A2BRmRNA（2^-△△Ct）及蛋白（灰度值）表达水平逐渐增加，以100μg／LTNF—α作用后A2BRmRNA及蛋白表达水平升高最为显著（分别为7．95±0．78和1．84±0．16）；用100μg／LTNF—d作用HPMECs不同时间后，随处理时间延长A2BR的mRNA（2。△act）和蛋白（灰度值）表达水平均逐渐增加，以作用24h升高最显著（分别为7．93±1．39和1．76±0．07）。②A2BR特异性激动剂／抑制剂干预实验：与空白对照组比较，TNF-α组细胞活性明显降低[（89．28±2．21）％比100％]，进入G1期的细胞数明显增多[（62．21±1．11）％比（34．40±0．47）％]，进入S＋G2期的细胞数明显减少[（37．79±1．11）％比（65．60±0．47）％]，VCAM-1和IL-1B蛋白表达明显增加[VCAM-1（灰度值）：12．94±1．18比1；IL-1B（灰度值）：3．03±0．23比1，均P〈0．01]。与TNF-α组比较，BAY＋TNF—α能显著逆转细胞活性下降和细胞周期阻滞，B＋T组细胞活性明显升高[（99．34±5．56）％比（89．28±2．21）％]，进入G1期的细胞数显著降低[（54．35±0．94）％比（62．21±1．11）％]，进入S＋G2期的细胞数明显升高[（45．65±0．94）％比（37．79±1．11）％]，VCAM-1（灰度值：7．54±0．95比12．94±1．18）和IL-1B（灰度值：0．71±0．06比3．03±0．23）蛋白表达明显降低（均P〈0．05）；PSB＋TNF-α诱导的细胞损伤进一步加重，P＋T组细胞活性下降为（82．59±2．98）％，进入G1期的细胞比例进一步升高达（71．77±0．29）％，进入S＋G2期细胞比例进一步下降为（28．23±7．22）％，VCAM-1和IL-1β蛋白表达（灰度值）分别增加到19．35±1．69和3．90±1．14，与TNF-α组比较差异均有统计学意义（均P〈0．05）。结论在TNF—d诱导的HPMECs炎性损伤中，A2BR表达上调；活化A2BR可以通过调节细胞活性和细胞周期、降低炎症因子的产生等，减轻TNF—α诱导的肺微血管内皮损伤和炎症反应。

盐酸石蒜碱对脂肪酸诱导H9c2细胞炎性损伤的保护作用及其机制

目的:研究盐酸石蒜碱(lycorine hydrochloride)对脂肪酸诱导H9c2细胞炎性损伤的保护作用及机制。方法:脂肪酸(100μmol/L)诱导H9c2细胞炎性损伤,采用CCK-8法筛选盐酸石蒜碱最佳给药浓度;蛋白免疫印迹法检测TLR4、p-PI3K、p-Akt、p-mTOR蛋白表达;荧光显微镜及流式细胞术检测H9c2细胞内活性氧(ROS)产生水平。结果:CCK-8筛选出盐酸石蒜碱的最佳给药浓度为5、10μmol/L。与正常对照组比较,模型组TLR4蛋白表达及p-PI3K/PI3K、ROS水平显著升高,p-Akt/Akt显著降低(P<0.05或P<0.01)。与模型组比较,盐酸石蒜碱组TLR4蛋白表达及p-PI3K/PI3K、p-mTOR/mTOR、ROS水平显著降低,p-Akt/Akt水平显著升高(P<0.05或P<0.01)。结论:盐酸石蒜碱对脂肪酸诱导H9c2细胞炎性损伤具有保护作用,其机制可能与抑制TLR4、p-PI3K、p-mTOR蛋白表达,促进Akt蛋白磷酸化,抑制炎性损伤H9c2细胞内ROS的产生有关。

二氢石蒜碱对棕榈酸诱导H9c2细胞炎性损伤的保护作用及其机制

目的:研究二氢石蒜碱对棕榈酸诱导H9c2细胞炎性损伤的影响并探讨其机制。方法:建立棕榈酸诱导H9c2细胞炎性损伤细胞模型,采用CCK-8法筛选二氢石蒜碱的最佳给药浓度。将培养的H9c2细胞随机分为正常对照组、模型组、LY294002组、雷帕霉素组及二氢石蒜碱低、中、高浓度组。蛋白免疫印迹法检测H9c2细胞中TLR4、p-PI3K、p-AKT、p-mTOR蛋白表达;免疫荧光染色及流式细胞术检测二氢石蒜碱对棕榈酸诱导H9c2细胞内活性氧(ROS)产生水平的影响。结果:采用棕榈酸100μmol/L建立H9c2细胞炎性损伤模型,CCK-8实验筛选出二氢石蒜碱组在1、10、50μmol/L下细胞存活率都在80%以上,分别确定为低、中、高给药浓度。蛋白免疫印迹实验表明,二氢石蒜碱预处理能显著下调棕榈酸诱导下H9c2细胞的TLR4、p-PI3K、p-mTOR蛋白表达,上调p-AKT蛋白表达(P<0.05或P<0.01),其作用呈浓度依赖性;PI3K/AKT抑制剂LY294002可抑制p-AKT蛋白表达,mTOR抑制剂雷帕霉素可抑制p-mTOR蛋白表达(P<0.01)。免疫荧光染色及流式细胞术结果表明二氢石蒜碱对炎性损伤H9c2细胞内ROS产生有显著的抑制作用(P<0.01)。结论:二氢石蒜碱对棕榈酸诱导的H9c2细胞炎性损伤具有保护作用,其机制可能与抑制TLR4、p-PI3K、p-mTOR蛋白表达,促进AKT蛋白磷酸化,抑制炎性损伤H9c2细胞内ROS的产生相关。

依托咪酯对脂多糖诱导人气道平滑肌细胞炎性损伤的改善作用及其机制

目的观察依托咪酯对脂多糖(LPS)诱导人气道平滑肌细胞(ASMCs)炎性损伤的改善作用,并探讨其机制。方法取对数生长期的人ASMCs分为对照组、LPS组、依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组。对照组常规培养ASMCs;LPS组加入500 ng/mL的LPS;依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组加入500 ng/mL的LPS后,再分别加入5µg/mL、10µg/mL、20µg/mL的依托咪酯。各组细胞继续培养72 h,采用ELISA法检测细胞中炎性因子IL-2、IL-6、TNF-α,采用MTT法测算细胞存活率,采用流式细胞法检测细胞凋亡率,采用荧光定量PCR法检测细胞中转化生长因子(TGF)-β1、Smad家族蛋白3(Smad3)mRNA,采用蛋白印迹法检测细胞中TGF-β1、Smad3蛋白。结果与对照组相比,LPS组、依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞中IL-2、IL-6、TNF-α水平均升高(P均<0.05);与LPS组相比,依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞中IL-2、IL-6、TNF-α水平均降低(P均<0.05),且依托咪酯中浓度组、依托咪酯高浓度组低于依托咪酯低浓度组(P均<0.05),依托咪酯高浓度组低于依托咪酯中浓度组(P<0.05)。对照组、LPS组、依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞存活率分别为100.00%、40.08%±6.04%、52.87%±6.21%、66.48%±7.10%、81.26%±9.54%,组间相比,P均<0.05。对照组、LPS组、依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞凋亡率分别为4.40%±1.09%、25.16%±5.07%、19.77%±4.03%、14.71%±2.25%、10.05%±2.05%,组间相比,P均<0.05。与对照组相比,LPS组、依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞中TGF-β1 mRNA和蛋白相对表达量、Smad3 mRNA和蛋白相对表达量均升高(P均<0.05);与LPS组相比,依托咪酯低浓度组、依托咪酯中浓度组、依托咪酯高浓度组细胞中TGF-β1 mRNA和蛋白相对表达量、Smad3 mRNA和蛋白相对表达量均降低(P均<0.05),且依托咪酯中浓度组、依托咪酯高浓度组低于依托咪酯低浓度组(P均<0.05),依托咪酯高浓度组低于依托咪酯中浓度组(P<0.05)。结论5µg/mL、10µg/mL、20µg/mL的依托咪酯对LPS诱导人ASMCs炎性损伤均具有改善作用,可升高细胞存活率、降低细胞凋亡率,且20µg/mL依托咪酯的的改善作用最强。依托咪酯对LPS诱导人ASMCs炎性损伤的改善作用机制可能与抑制TGF-β1/Smad3信号通路的激活有关。

cGAS/STING通过NLRP3炎性小体调控人肺微血管内皮细胞炎症的作用机制

目的探讨鸟嘌呤核苷酸腺嘌呤核苷酸合成酶(cGAS)/干扰素激活蛋白(STING)通过NOD样受体蛋白3(NLRP3)炎性小体调控人肺微血管内皮细胞(HPMVECs)炎症的作用机制。方法原代培养HPMVECs,进行脂多糖(LPS)量效实验及cGAS、STING和NLRP3抑制干预实验。(1)量效实验:以50、100、1000 ng/ml的LPS作用24 h后(分别为50 ng/mlLPS组、100 ng/mlLPS组、1000 ng/ml LPS组),用实时荧光反转录-聚合酶链反应(qRT-PCR)和蛋白质免疫印迹试验(Western Blot)分别检测cGAS、STING和NLRP3表达。(2)cGAS抑制干预实验:使用cGAS(siRNA)转染,再加入100 ng/ml的LPS处理24 h;同时设立空白对照组、LPS刺激组、siRNA单独处理组,采用WesternBlot检测STING、NLRP3,及NLRP3下游因子白介素(IL)-1β和IL-18的表达。(3)STING抑制干预实验:使用STING(siRNA)转染,再加入100 ng/ml的LPS处理24 h;同时设立空白对照组,采用WesternBlot检测cGAS、NLRP3,及NLRP3下游因子IL-1β和IL-18的蛋白表达。(4)NLRP3抑制干预实验:使用NLRP3炎性小体抑制剂MCC950预处理30 min,再加入100 ng/ml的LPS处理24 h;同时设立空白对照组,采用WesternBlot检测cGAS、STING,及NLRP3下游因子IL-1β和IL-18的蛋白表达。结果(1)量效实验:与空白对照组比较,HPMVECs中cGAS、STING、NLRP3的mRNA水平和蛋白表达均显著升高,差异有统计学意义(P<0.05)。(2)cGAS抑制干预实验:与空白对照组比较,LPS刺激HPMVECs,cGAS表达水平显著升高,差异有统计学意义(P<0.05);与LPS刺激组比较,抑制cGAS时,siRNA+LPS处理组STING、NLRP3及其下游因子IL-1β、IL-18的表达水平均显著降低,差异有统计学意义(P<0.05)。(3)STING抑制干预实验:与空白对照组比较,LPS刺激HPMVECs,STING表达水平显著升高,差异有统计学意义(P<0.05);与LPS刺激组比较,抑制STING时,NLRP3及其下游因子IL-1β、IL-18的表达水平均显著降低,差异有统计学意义(P<0.05),而cGAS的表达水平无显著降低(P>0.05)。(4)NLRP3抑制干预实验:与空白对照组比较,LPS刺激HPMVECs,siRNA+LPS处理组NLRP3表达水平显著升高,差异有统计学意义(P<0.05);与LPS刺激组比较,抑制NLRP3显著降低了NLRP3下游因子白细胞IL-1β和IL-18的表达,差异有统计学意义(P<0.05),而cGAS和STING的表达水平无显著降低;差异无统计学意义(P>0.05)。结论(1)LPS刺激下,在HPMVECs中cGAS、STING、NLRP3、IL-1β和IL-18的表达水平均显著升高,参与调控炎症反应;(2)cGAS/STING/NLRP3信号通路顺序参与调控PMVECs炎症作用。

Role of interleukin 18 in acute lung inflammation induced by gut ischemia repeifusion

AIM: To study the changes of endogenous interleukin 18 (IL-18) levels and evaluate the role of IL-18 on lung injury following gut ischemia/reperfusion.METHODS: A superior mesenteric artery occlusion model was selected for this research. The mice were randomly divided into four groups: Sham operation (sham), ischemia (0.5 h) followed by different times of reperfusion (I/R),and I/R pretreated with exogenous IL-18 (I/R+IL-18) or IL-18 neutralizing antibody (I/R+IL-18Ab) 15 min before ischemia. Serum IL-18 levels were detected by Western blot and ELISA, and the levels of IL-18 in lung tissue were evaluated by immunohistochemical staining. For the study of pulmonary inflammation, the lung myeloperoxidase (MPO) contents and morphological changes were evaluated.RESULTS: Gut ischemia/reperfusion induced rapid increase of serum IL-18 levels, peaked at 1 h after reperfusion and then declined. The levels of IL-18 in lung tissue were gradually enhanced as the progress of reperfusion.Compared with I/R group, exogenous administration of IL-18 (I/R+IL-18) further remarkably enhanced the pulmonary MPO activity and inflammatory cell infiltration,and in I/R+IL-18Ab group, the content of MPO were significantly reduced and lung inflammation was also decreased.CONCLUSION: Gut ischemia/reperfusion induces the increase of IL-18 expression, which may make IL-18 act as an important proinflammatory cytokine and contribute to gut ischemia/reperfusion-induced lung inflammation.

Association between TRAIL expression on peripheral blood lymphocytes and liver damage in chronic hepatitis B

AIM:To explore a novel mechanism for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), upregulation of CD4+ and CD8+T lymphocytes participating in the patho-physiological process of chronic hepatitis B (CHB). METHODS: The levels of serum soluble TRAIL (sTRAIL), serum IFN-γ and membrane-bound TRAIL expression on peripheral leucocytes from 58 CHB patients were examined by ELISA and flow cytometry respectively. The levels of TRAIL were compared with the baseline levels of 17 healthy controls, and correlation analysis was performed between ALT, TBIL, PT, morphological change in hepatic tissues, and serum IFN-γ. RESULTS: The results showed that TRAIL levels on membranes of CD4+, CD8+ T cells in CHB patients were much higher than those in healthy controls (P<0.001), and were correlated with serum TBIL (r=0.354, P= 0.008 for CD4+ and r= 0.522, P= 0.000 for CD8+, respectively), ALT (r= 0.393, P= 0.003 for CD8+), PT (r = 0.385, P = 0.004 for CD8+) and serum IFN-y level (r = 0.302, P= 0.011 for CD4+ and r= 0.307, P= 0.009 for CD8+). On the contrary to membrane-bound TRAIL expression, serum level of sTRAIL was not correlated with that of TBIL and PT, though it was higher than that of the normal population and was positively correlated with serum HBeAg expression (r= 0.695, P = 0.001). CONCLUSION: The expression level of TRAIL on the membrane of lymphocytes was upregulated and associated with the liver injury in CHB patients. These findings suggest that upregulation of TRAIL expression may be induced by virus antigen and inflammatory cytokine IFN-γ.

Effects of penehyclidine hydrochloride in small intestinal damage caused by limb ischemia-reperfusion

AIM:To investigate the protective effect of penehyclidine hydrochloride post-conditioning in the damage to the barrier function of the small intestinal mucosa caused by limb ischemia-reperfusion(LIR) injury. METHODS:Male Wistar rats were randomly divided into three groups(36 rats each) :the sham-operation group(group S) ,lower limb ischemia-reperfusion group(group LIR) ,and penehyclidine hydrochloride postconditioning group(group PHC) .Each group was divided into subgroups(n=6 in each group) according to ischemic-reperfusion time,i.e.immediately 0 h(T1) ,1 h(T2) ,3 h(T3) ,6 h(T4) ,12 h(T5) ,and 24 h(T6) .Bilateral hind-limb ischemia was induced by rubber band application proximal to the level of the greater trochanter for 3 h.In group PHC,0.15 mg/kg of penehyclidine hydrochloride was injected into the tail vein immediately after 3 h of bilateral hind-limb ischemia.The designated rats were sacrificed at different time-points of reperfusion;diamine oxidase(DAO) ,superoxide dismutase(SOD) activity,myeloperoxidase(MPO) of small intestinal tissue,plasma endotoxin,DAO,tumor necrosis factor-α(TNF-α) ,and interleukin(IL) -10 in serum were detected in the rats. RESULTS:The pathological changes in the small intestine were observed under light microscope.The levels of MPO,endotoxin,serum DAO,and IL-10 at T1-T6,and TNF-αlevel at T1-T4 increased in groups LIR and PHC(P<0.05) compared with those in group S,but tissue DAO and SOD activity at T1-T6 decreased(P<0.05) .In group PHC,the tissue DAO and SOD activity at T2-T6,and IL-10 at T2-T5 increased to higher levels than those in group LIR(P<0.05) ;however,the levels of MPO,endotoxin,and DAO in the blood at T2-T6,and TNF-αat T2 and T4 decreased(P<0.05) . CONCLUSION:Penehyclidine hydrochloride post-conditioning may reduce the permeability of the small intestines after LIR.Its protection mechanisms may be related to inhibiting oxygen free radicals and inflammatory cytokines for organ damage.

Mutations in hepatitis B virus core regions correlate with hepatocellular injury in Chinese patients with chronic hepatitis B

AIM: To elucidate the relationship between the frequency of core mutations and the clinical activity of hepatitis B virus (HBV)-related liver disease and to characterize the amino acid changes in the core region of HBV.METHODS: We studied 17 Chinese patients with chronic hepatitis B according to their clinical courses and patterns of the entire core region of HBV.RESULTS: Amino acid changes often appeared in the HBV core region of the HBV gene in patients with high values of alanine aminotransferase (ALT) or with the seroconversion from HbeAg to anti-HBe. The HBV core region with amino acid changes had high frequency sites that corresponded to HLA Ⅰ/Ⅱ restricted recognition epitopes reported by some investigators.CONCLUSION: The core amino acid changes of this study occur due to influence of host immune system. The presence of mutations in the HBV core region seems to be important for predicting the clinical activity of hepatitis B in Chinese patients.

Punicalagin protects bovine endometrial epithelial cells against lipopolysaccharide-induced inflammatory injury

Objective：Bovine endometritis is one of the most common reproductive disorders in cattle.The aim of this study was to investigate the anti-inflammation potential of punicalagin in lipopolysaccharide（LPS）-induced bovine endometrial epithelial cells（bE ECs）and to uncover the underlying mechanisms.Methods：bE ECs were stimulated with different concentrations（1,10,30,50,and 100μg/ml）of LPS for 3,6,9,12,and 18 h.MTT assay was used to assess cell viability and to identify the conditions for inflammatory injury and effective concentrations of punicalagin.Quantitative real-time polymerase chain reaction（q RT-PCR）was used to assess gene expression of pro-inflammatory cytokines.Western blotting was used to assess levels of inflammation-related proteins.Results：Treatment of b EECs with 30μg/ml LPS for 12 h induced cell injury and reduced cell viability.Punicalagin（5,10,or 20μg/ml）pretreatment significantly decreased LPS-induced productions of interleukin（IL）-1β,IL-6,IL-8,and tumor necrosis factor-α（TNF-α）in bE ECs.Molecular research showed that punicalagin inhibited the activation of the upstream mediator nuclear factor-κB（NF-κB）by suppressing the production of inhibitorκBα（IκBα）and phosphorylation of p65.Results also indicated that punicalagin can suppress the phosphorylation of mitogen-activated protein kinases（MAPKs）including p38,c-Jun N-terminal kinase（JNK）,and extracellular signal-regulated kinase（ERK）.Conclusions：Punicalagin may attenuate LPS-induced inflammatory injury and provide a potential option for the treatment of dairy cows with Escherichia coli endometritis.

Clodronate-superparamagnetic iron oxide-containing liposomes attenuate renal injury in rats with severe acute pancreatitis

Background and objective： It has been shown that macrophages play an important role in the development of severe acute pancreatitis （SAP）, and eventually lead to multiple organ failure （MOF）. Clodronate-liposome selectively depleted macrophages. This study was to investigate the role of renal macrophage infiltration in acute renal injury in rats with SAP and to evaluate the potential of superparamagnetic iron oxide （SPIO）-enhanced magnetic resonance imaging （MRI） for diagnosis. Methods： Superparamagnetic Fe3O4 nanoparticles were prepared by chemical coprecipitation. SPIO-liposomes and SPIO-clodronate-liposomes were prepared by the thin film method. SAP models were prepared by injection of sodium taurocholate into the subcapsular space of rat pancreas. Sprague-Dawley rats were randomly divided into a control group, SAP plus SPIO-liposome （P） group, and SAP plus SPIO-clodronatecontaining liposome （T） group. Kidney injury was evaluated by T2-weighted MRI scan. The levels of serum amylase （SAM）, blood urea nitrogen （BUN）, and serum creatinine （SCr） were measured by an automated enzymatic method. Serum tumor necrosis factor-α （TNF-α） was measured by enzyme-linked immunosorbent assay （ELISA）. Pathological changes in the pancreas and kidney were observed using hematoxylin and eosin （H＆E） staining, while cell apoptosis was detected with terminal deoxynucleotidyl transferase dUTP nick end labeling （TUNEL） staining. In addition, the macrophage markers （CD68） of the renal tissue were detected with immunohistochemistry. Results： The pathological changes in the pancreas and kidneys of rats in the T group were milder than those in the P group. The MRI signal intensity of the kidneys in the P and T groups was significantly lower than that in the control group. There were significant changes in the two experimental groups （P〈0.01）. The levels of SAM, Bun, SCr, and TNF-α in rats in the P group were higher than those in the control group （P〈0.01） and in the T group （P〈0.01）. The apoptosis of the kidney in the T group was higher than that in the P group at 2 and 6 h （P〈0.01）. Conclusions： Clodronate-containing liposomes protected against renal injury in SAP rats, and SPIO can be used as a tracer for MRI examination to detect renal injury in SAP rats. SPIO-aided MRI provided an efficient non-invasive way to monitor the migration of macrophages after renal injury in rats with SAP.