骨髓间充质干细胞对烟雾吸入性损伤兔早期炎症因子分泌的影响

目的 探讨骨髓间充质干细胞(MSCs)对烟雾吸入性损伤早期外周血及肺组织中肿瘤坏死因子-α(TNF-α)、白细胞介素(IL-1β、IL-6、IL-10)分泌的影响.方法 全骨髓培养法体外培养兔MSCs,用流式细胞术鉴定.将56只健康新西兰大耳白兔按随机数字表法分为正常对照组(C组,n=8)、烟雾吸入性损伤组(S组,n=24)、烟雾吸入性损伤+MSCs移植组(M组,n=24),后两组再分为伤后2、4、6 h亚组,每组8只.采用酶联免疫吸附法(ELISA)检测血浆及肺组织匀浆液中促炎因子TNF-α、IL-1β、IL-6及抗炎因子IL-10的含量.结果 与C组比较,S组各时间点血浆促炎、抗炎因子均显著升高;各时间点肺组织促炎因子显著升高,抗炎因子无明显变化.与S组比较,M组各时间点血浆促炎因子显著下降,抗炎因子显著升高[6 h时TNF-α(μg/L):1.7±1.7比4.1±1.6,IL-1β(ng/L):9.9±1.7比21.2±2.6,IL-6(μg/L):1.0±0.3比1.3±0.2,IL-10(ng/L):15.2±4.4比7.9±3.5,均P＜0.05];各时间点肺组织促炎因子显著降低,而抗炎因子仅在4 h、6 h显著升高[6 h时TNF-α(ng/L):503.0±156.4比587.7±171.2,IL-1β(ng/L):0.4±0.2比0.6±0.2,IL-6(ng/L):155.2±13.7比350.2±20.3,IL-10(ng/L):23.3±5.4比11.0±5.6,均P＜0.05].结论 MSCs移植能降低烟雾吸入性损伤早期促炎因子水平,升高抗炎因子水平,改善全身炎症反应,对烟雾吸入性损伤肺组织具有一定的保护作用.

Abstract：

Objective To explore the effect of bone marrow mesenchymal stem cells (MSCs) engraftment on secretion of tumor necrosis factor-α (TNF-α), interleukins (IL-1β, IL-6, IL-10) in peripheral blood and lung homogenates in the early stages of smoke inhalation injury. Methods MSCs were proliferated by the method of whole marrow culture and identified by flow cytometry. Fifty-six healthy New Zealand rabbits were randomly divided into control group (C group, n=8), smoke inhalation injury group (S group, n=24)and smoke inhalation injury+MSCs engraftment group (M group, n=24). The latter two groups were subdivided into 2, 4, 6 hours after injury subgroups, with 8 rabbits in each group. The levels of TNF-α,IL-1β, IL-6 and IL-10 in peripheral blood and lung homogenates were measured by enzyme-linked immunosorbent assay (ELISA). Results Compared with C group, concent of pro-inflammatory and anti-inflammatory cytokines in peripheral blood at each time point in S group were increased significantly.The concent of pro-inflammatory cytokines in lung homogenate at each time point in S group was significantly higher than thoae in C group, and that of anti-inflammatory cytokines showed no significant changes.Compared with the S group, concent of pro-inflammatory cytokines in peripheral blood in M group was decreased significantly, and that of anti-inflammatory cytokines was increased significantly [6 hours TNF-α(μg/L):1.7±1.7 vs. 4.1±1.6, IL-1β (ng/L): 9.9±1.7 vs. 21.2±2.6, IL-6 (μg/L): 1.0±0.3 vs.1.3 ± 0. 2, IL-10 (ng/L): 15. 2 ± 4. 4 vs. 7. 9 ± 3.5, all P＜0.05]. Concent of pro-inflammatory cytokines at each time point in M group was decreased significantly when compared with S group in lung homogenate,while only anti-inflammatory cytokine at 4 hours and 6 hours was increased significantly [6 hours TNF-α (ng/L): 503. 0±156. 4 vs. 587.7±171.2, IL-1β (ng/L): 0.4±0.2 vs. 0.6±0.2, IL-6 (ng/L): 155.2±13.7 vs. 350.2±20.3, IL-10 (ng/L): 23.3±5.4 vs. 11.0±5.6, all P＜0.05]. Conclusion MSCs engraftment could decrease pro-inflammatory cytokines and increase anti-inflammatory cytokines in the early stages of smoke inhalation injury, thus amelioratea inflammatory reaponse, which confers protective effect on smoke inhalation injury.     

多器官功能障碍综合征大鼠肺组织血栓调节蛋白和基质金属蛋白酶-9的表达

Objective To determine the expressions of thrombomodulin (TM) and matrix metalloproteinase-9(MMP-9) in the lung of rats with multiple organ dysfunction syndrome (MODS) and to investigate the mechanism of lung injury in MODS. Method Forty adult mule Sprague-Dawley (SD) rats were randomly divided into two groups,namely the normal control group and the MODS model group. The rats of model group were further divided into four subgroups as per different intervals (6 h, 12 h, 24 h and 48 h) ,and there were 8 rats in each groups. The animal models of MODS were estabhshed by two hits,the left eyeball of each model rat was removed to bleed to 2 mL/100g,and four hours later, lipopolysaccharide (LPS 5 mg/kg) was injected into intraperitoneal cavity of model rats. The same volume of saline was injected intraperitoneally into rats of control group instead of LPS. All rats were sacrificed at various intervals. The histological changes in lung tissue were observed by naked eye and light microscope. The expressions of TM and MMP-9 proteins were deteceted by using immunohistechemistry. One-way ANOVA was used for comparison among multiple group. Results (1)There were no histopathological changes in lung of rats of control group, and the lung injury was serious in MODS rots. (2) Compared with the rots of con-trol group, the expression of TM in lung tissue of MODS rats increased 6 hours after LPS, reached peak 12 hours later(P <0.01),and then decreased during 24～48 period.There was no significant difference in expression of TM between two groups 48 hours later. Compared with control group, the expressions of MMP-9 in lung tissue of MODS rats didn't significantly increase 6 ～ 48 hours after LPS (P < 0.01). Conclusions There are endothelium damage and extracellular matrix damage found in the lung tissue of rats at the early phase of MODS. TM and MMP-9 are good biomarkers of endothelium and extracellular matrix damage, and they can be used for diagnosing and es-timating the severity of injury lungs at the early phase of MODS.     

骨髓间充质干细胞治疗大鼠百草枯中毒急性肺损伤的作用

目的 观察骨髓间充质干细胞(MSCs)防治大鼠百草枯(PQ)中毒急性肺损伤的作用及可能机制.方法 80只SPF级Wistar大鼠随机(随机数字法)分为4组,每组20只:肺损伤组、MSCs治疗组、MSCs对照组和正常对照组.腹腔注射质量分数为20%的百草枯18 mg/kg制备大鼠中毒模型,正常对照给予磷酸缓冲液(PBS).取第4代MSCs,加入携带增强型绿色荧光蛋白基因的腺病毒载体Ad5-EGFP,转染成功后,在染毒后4 h经尾静脉注射入大鼠体内,分别在给予MSCs后1 d,3 d,7 d,28 d时随机处死每组大鼠各5只,行肺组织病理切片,荧光倒置显微镜观察骨髓间充质干细胞的迁移,于28 d处死各组大鼠取相应标本,检测肺系数、肺匀浆中羟脯氨酸(HYP)的含量、血清转化生长因子-β1(TGF-β1),同时行肺组织病理学观察.结果 肺组织病理学观察显示,MSCs治疗组肺纤维化及实变程度较肺损伤组轻,血清转化生长因子-β1(TGF-β1)和肺系数、肺匀浆中经脯氨酸(HYP)的含量均好于损伤组,差异有统计学意义(P均＜0.05).结论 MSCs注入百草枯中毒大鼠体内,通过抑制TGF-β1水平,减少纤维母细胞迁移、活化,抑制胶原蛋白产生,进而保护肺组织结构,可以更有效地抑制肺纤维化、肺实变.

Abstract：

Objective To explore the possible mechanism and protective effect of mesenchymal stem cell (MSC) on rats with paraquat-induced acute lung injury. Method The solution of 20% paraquat (PQ) in dose of 18 mg/kg was injected intra-peritoneally into rats to induce poisoning,and phosphate buffered solution (PBS) was given to rats instead of PQ in rats of control group. Eighty specific pathogen free (SPF) Wistar rats were randomly divided into four group: PQ plus PBS group (n = 20), PQ plus MSCs group (n = 20), MSCs plus PBS group (n=20), normal group (n = 20). The forth generation of MSCs were transfected with Ad5-EGFP virus vector, and then the MSCs-EGFP was delivered to rats through the tail vein of rats 4h after PQ. Five rats of each group were sacrificed 1 d, 3 d, 7 d and 28 days after MSCs administration, and lung tissues of rats were taken to make sections for histological observation of the migration of MSCs under fluorescence inverted microscope. The lung tissues of rats sacrificed on the 28 th day after PQ poisoning were taken for detecting pulmonary coefficient and the content of hydroxyproline (HYP) in the lung tissue homogenate, and at the same time, the levels of serum transforming growth factor-β1(TGF-β1) were assayed. Results The pathological changes of lung tissue showed that the pulmonary fibrosis and consolidation in the MSCs treatment group were milder than those in PQ poisoning model group. In the MSCs treatment group, the levels of serum TGF-β1 and lung tissue HYP, and pulmonary coefficient were lower than those of PQ poisoning model group (P＜0.05). Conclusions The use of MSCs for treatment of paraquat intoxication can protect pulmonary structure by decrease in TGF-B1 and inhibiting the fibroblast migration, suppressing the production of collagenous protein.     

The role of erlotinib in the acute lung injury and the expression of surfactant protein A北大核心CSCD

Objective: To investigate the role of erlotinib in the expression of surfactant protein A (SP-A) in LPS-induced acute lung injury (ALI) of mice model. Methods: C57BL/6 mice were randomly (random number) divided into control group (n=6), ER group (n=6), LPS group (n=6), and ER+LPS group (n=6). In the LPS group, 2 mg/kg LPS was instilled into trachea of mice to induce lung injury. In control group, normal saline was instilled into trachea of mice instead. In the ER+LPS group and ER group, 100 mg/kg of erlotinib was instilled into stomach of mice, and one hour later. 2 mg/kg LPS was instilled into trachea of mice in ER+PLS group to induce lung injury. Twenty-four hours later, bronchoalveolar lavage fluid (BALF) and lung tissue of mice in four groups were collected. HE staining were used for evaluating pathological changes of lung injury. Lung wet/dry weight ratio, protein concentrations and total cell numbers in the BALF were measured to determine the degree of pulmonary edema. Immunohistochemical staining and Western Blot were used for testing the protein expression of SP-A, Data of multiple groups were analyzed by one way variance (ANOVA) and inter-group comparisons were made by the least significant difference (LSD) tests. Results: There was no significant difference in lung injury score (LIS) between control group (0.056±0.008) and ER (0.064±0.037) group, The LIS in LPS group (0.846±0.047) was higher than that in control group, however the LIS in ER+LPS group (0.279±0.020) was significant lower than that in LPS group (P < 0.05). Lung wet/dry weight, SP-A concentration and total cell numbers in the bronchoalveolar lavage fluid revealed that the degree of pulmonary edema in LPS group was higher than that in control group, and this pulmonary edema was reversed by erlotinib treatment. Immunohistochemical staining and Western blot showed that the expression of SP-A in LPS group was decreased compared with control group, but it was recovered after erlotinib treatment (P < 0.05). Conclusions: Erlotinib could protect the LPS-induced ALI, and it may be related to the regulation of SP-A. © 2018 Chinese Medical Association. All rights reserved.     

Mesenchymal stem cells transplantation improves functional recovery after cardiac arrest: Contribution of necroptosis北大核心CSCD

Objective To explore the effects of bone marrow mesenchymal stem cells (MSCs) transplantation on receptor-interacting protein kinase 1 (RIP1) and RIP3 in rat brain after cardiac arrest (CA). Methods Sprague Dawley (SD) rats were randomly (random number) divided into sham group (n=8), CA group (n=8) and MSCs group (n=8). Animals were subjected to asphyxial cardiac arrest and followed by cardiopulmonary resuscitation (CPR). In MSCs group or CA group, animals received intravenous injection of 1 x 106 MSCs in 0.5 mL phosphate buffer solution (PBS) or 0.5 mL PBS alone at 1 h after successful resuscitation. Neurological deficit scores (NDS) were assessed at 3 d after CPR. Donor MSCs in brain were detected under a fluorescent microscope. HE staining of brain tissue was performed to observe necrotic neurons. Western blot analysis was performed to measure the levels of RIP 1 and RIP3 in brain. Multiple comparisons were made by analysis of variance or Kruskal-Wallis H test. Results At 3 d after CPR, MSCs group demonstrated higher NDS than CA group [72.5(71.5,73.2) vs. 63.0(62.5,64.1), Z=3.376, P=0.001]. DAPI-labeled MSCs were primarily observed in the cerebral cortex. The percentage of necrotic neurons' in MSCs group was significantly lower than that in CA group [(29.6±5.9)% vs. (57.2±6.4)%, t=8.922, P<0.01]. The levels of RIP1 and RIP3 expression in brain in MSCs group were significantly lower than those in CA group [RIP1: 0.227(0.193,0.243) vs. 0.599(0.535,0.629), Z=3.151, P=0.001; RIP3: 0.217(0.203,0.274) vs. 0.543(0.533,0.555), Z=3.361, P=0.001]. Conclusion MSCs transplantation improves neurological function after CPR from CA in rats likely associated with inhibiting necroptosis. © 2018 Chinese Medical Association. All Rights Reserved.     

Expression of phosphatidylinositol-3 kinase and effects of inhibitor Wortmannin on expression of tumor necrosis factor-α in severe acute pancreatitis associated with acute lung injury

BACKGROUND: Acute lung injury(ALI) is a common and serious complication of severe acute pancreatitis(SAP). The study aimed to investigate the protective effect and mechanism of phosphatidylinositol-3 kinase(PI3K) inhibitor Wortmannin in SAP associated with ALI.METHODS: Ninety rats were randomly divided into three groups: sham operation(SO) group(n=30), SAP group(n=30), and SAP+Wortmannin(SAP+W) group(n=30). SAP model was induced by retrograde injection of 4% sodium taurocholate into the biliopancreatic duct of rats. The rate of lung water content, myeloperoxidase(MPO), matrix metalloproteinase 9(MMP-9), protein kinase B(PKB), abdphosphorylation of protein kinase B(P-PKB) activity in the lung tissue were evaluated.RESULTS: In the SAP group, the p-PKB expression in the lung tissue began to rise at 3 hours after modeling, and peaked at 12 hours(P0.05); the rate of lung water content, MPO and TNF-α activity were also gradually increased, and the degree of lung lesion gradually increased(P0.05). In the SAP+Wortmannin group, the p-PKB expression in the lung tissue began to rise at 3 hours after modeling, and peaked at 12 hours; it was higher than that in the SO group(P0.05), but significantly lower than that in the SAP group(P0.05). The rest indicators in the SAP+Wortmannin group were also significantly decreased as compared with the SAP group(P0.05).CONCLUSIONS: The expression of phosphatidylinositol-3 kinase/protein kinase B was elevated in severe pancreatitis rats with lung injury. This suggested that PI3 K signal transduction pathway is involved in the control and release of proinfl ammatory cytokines TNF-α, which may play an important role in the pathogenesis of severe acute pancreatitis associated with lung injury. This finding indicated that Wortmannin can block the PI3 K signal transduction pathway, and inhibit the release of infl ammatory factor TNF-α.     

Change of alveolar epithelial type Ⅱ cells and pulmonary surfactant protein A in young rats with acute lung injury

Objective To study the temporal changes of alveolar epithelial type Ⅱ cells and surfactant pro-tein A in young rats with acute lung injury induced by lipopolysaecharide. Method Totally 110 SD young rats (male:53, female : 57) were randomly divided into ALI and normal control groups (six subgroups in each group).LPS(4 mg/kg) was given intraperitoneally in ALI group. The same amount of normal saline was given in the con-trol groups. Eight rats in each subgroup were sacrificed at 6, 12, 24, 36, 48 and 72 hours after the injection.Lung samples were taken for transmission electron microscope examination. RT-PCR was epmloyed for the mea-surement of SP-A mRNA. Western blot was used for the detection of SP-A in the lung tissue. ANOVA and homo-geneity of variance test were performed by SPSS 12.0. Results The microvilli disappeared at 24 hours after the injection of LPS. The number of lamellar body (LBs) was provisionality increased at 24 hours and 48 hours. The ring-like an'angement of LBs around nucleus and the giant LB with vacuole-like deformity were found as the main characteristics of AEC- Ⅱ in ALI at 48 hours. The number of LBs reduced and broken and residual LB remained at 72 hours. SP-A elevated greatly from 24 to 48 hours (P < 0.01), reached peak at 36 hours (6.94 ± 0.80, P <0.01),reached the lowest level(3.87 ±0.50, P <0.01)at 72 hours. Conclusions The pathological changes of AEC-Ⅱ and SP-A in lung tissue wiht ALI are time-dependent. The typical alterations of AEC- Ⅱ occurs at 48 hours accompanied by the compensatory increase of SP-A. AEC- Ⅱ is seriously injuried with the typical changes of LBs and the diminishing of SP-A in lung tissue.     

Change of alveolar epithelial type Ⅱ cells and pulmonary surfactant protein A in young rats with acute lung injury

Objective To study the temporal changes of alveolar epithelial type Ⅱ cells and surfactant pro-tein A in young rats with acute lung injury induced by lipopolysaecharide. Method Totally 110 SD young rats (male:53, female : 57) were randomly divided into ALI and normal control groups (six subgroups in each group).LPS(4 mg/kg) was given intraperitoneally in ALI group. The same amount of normal saline was given in the con-trol groups. Eight rats in each subgroup were sacrificed at 6, 12, 24, 36, 48 and 72 hours after the injection.Lung samples were taken for transmission electron microscope examination. RT-PCR was epmloyed for the mea-surement of SP-A mRNA. Western blot was used for the detection of SP-A in the lung tissue. ANOVA and homo-geneity of variance test were performed by SPSS 12.0. Results The microvilli disappeared at 24 hours after the injection of LPS. The number of lamellar body (LBs) was provisionality increased at 24 hours and 48 hours. The ring-like an'angement of LBs around nucleus and the giant LB with vacuole-like deformity were found as the main characteristics of AEC- Ⅱ in ALI at 48 hours. The number of LBs reduced and broken and residual LB remained at 72 hours. SP-A elevated greatly from 24 to 48 hours (P < 0.01), reached peak at 36 hours (6.94 ± 0.80, P <0.01),reached the lowest level(3.87 ±0.50, P <0.01)at 72 hours. Conclusions The pathological changes of AEC-Ⅱ and SP-A in lung tissue wiht ALI are time-dependent. The typical alterations of AEC- Ⅱ occurs at 48 hours accompanied by the compensatory increase of SP-A. AEC- Ⅱ is seriously injuried with the typical changes of LBs and the diminishing of SP-A in lung tissue.     

Change of alveolar epithelial type Ⅱ cells and pulmonary surfactant protein A in young rats with acute lung injury

Objective To study the temporal changes of alveolar epithelial type Ⅱ cells and surfactant pro-tein A in young rats with acute lung injury induced by lipopolysaecharide. Method Totally 110 SD young rats (male:53, female : 57) were randomly divided into ALI and normal control groups (six subgroups in each group).LPS(4 mg/kg) was given intraperitoneally in ALI group. The same amount of normal saline was given in the con-trol groups. Eight rats in each subgroup were sacrificed at 6, 12, 24, 36, 48 and 72 hours after the injection.Lung samples were taken for transmission electron microscope examination. RT-PCR was epmloyed for the mea-surement of SP-A mRNA. Western blot was used for the detection of SP-A in the lung tissue. ANOVA and homo-geneity of variance test were performed by SPSS 12.0. Results The microvilli disappeared at 24 hours after the injection of LPS. The number of lamellar body (LBs) was provisionality increased at 24 hours and 48 hours. The ring-like an'angement of LBs around nucleus and the giant LB with vacuole-like deformity were found as the main characteristics of AEC- Ⅱ in ALI at 48 hours. The number of LBs reduced and broken and residual LB remained at 72 hours. SP-A elevated greatly from 24 to 48 hours (P < 0.01), reached peak at 36 hours (6.94 ± 0.80, P <0.01),reached the lowest level(3.87 ±0.50, P <0.01)at 72 hours. Conclusions The pathological changes of AEC-Ⅱ and SP-A in lung tissue wiht ALI are time-dependent. The typical alterations of AEC- Ⅱ occurs at 48 hours accompanied by the compensatory increase of SP-A. AEC- Ⅱ is seriously injuried with the typical changes of LBs and the diminishing of SP-A in lung tissue.     

Effects of bone marrow-derived mesenchymal stem cells engraftment on vascular endothelial cell growth factor in lung tissue and plasma at early stage of smoke inhalation injury

BACKGROUND:

This study was undertaken to determine the effect of mesenchymal stem cells (MSCs) engraftment on vascular endothelial cell growth factor (VEGF) in lung tissue, plasma and extravascular lung water at early stage of smoke inhalation injury.

METHODS:

A rabbit smoke inhalation injury model was established using a home-made smoke inhalation injury generator, and rabbits were divided into two groups randomly: a control group (S group, n=32) and a MSCs treatment group (M group, n=32). 10 ml PBS was injected via the ear marginal vein immediately at injury into the S group. Third generation MSCs with a concentration of 1×10⁷/10 ml PBS were injected via the ear marginal vein immediately at injury into the M group. VEGF in peripheral blood and lung tissue were measured at 0 (baseline), 2, 4 and 6 hours after injection respectively and analyzed. The right lungs of rabbits were taken to measure lung water mass fraction.

RESULTS:

In the lung tissue, VEGF decreased gradually in the S group (P<0.05) and significantly decreased in the M group (P<0.05), but it increased more significantly than the values at the corresponding time points (P<0.05). In peripheral blood, VEGF increased gradually in the S group (P<0.05) and markedly increased in the M group (P<0.05), but it decreased more significantly than the values at corresponding time points (P<0.05).

CONCLUSION:

MSCs engraftment to smoke inhalation injury could increase VEGF in lung tissue, decrease VEGF in plasma and reduce extravascular lung water, indicating its protective effect on smoke inhalation injury.KEY WORDS: Mesenchymal stem cells, Smoke inhalation injury, Vascular endothelial cell growth factor, Extravascular lung water, Rabbit     

骨髓间充质干细胞对烟雾吸入性损伤早期血管内皮细胞生长因子的影响

目的 探讨骨髓间充质干细胞(bone marrow-derived mesenchymal stem cells,MSCs)对烟雾吸入性损伤早期肺组织和血浆中血管内皮细胞生长因子(vascular endothelial cell growth factor,VEGF)以及血管外肺水的影响.方法 烟雾吸入性损伤模型达成后,64只兔随机(随机数字法)分成2组:致伤组(S组,n=32)和治疗组(M组,n=32).S组伤后立即经耳缘静脉注入10 mL PBS液;M组伤后立即经耳缘静脉注入含兔第三代1×107个MSCs的PBS液10 mL.两组分别于伤前、伤后2 h,4 h和6h抽血后取兔肺组织,ELISA方法检测血浆和肺组织VEGF含量.伤后6 h另取肺组织作肺水质量分数测定.结果 致伤后肺组织VEGF在S组逐渐降低(P＜0.05),而M组虽然也呈降低趋势(P＜0.05),但与S组对应时间点相比却显著上升(P＜0.05);血浆VEGF在S组逐渐升高(P＜0.05),M组虽然也呈升高趋势(P＜0.05),但与S组对应时间点相比却明显下降(P＜0.05).实验6 h,M组肺水质量分数明显低于S组(P＜0.05).结论 MSCs移植能升高早期烟雾吸入性损伤肺组织VEGF水平,降低外周血VEGF水平,减少血管外肺水,对烟雾吸入性损伤可能具有一定的保护作用.     

Effects of an L-selectin antibody on the pulmonary and systemic manifestations of severe smoke inhalation injuries in sheep

Sheep were treated with either lymphocyte adhesion molecule (LAM)1-3, an antibody against L-selectin, (40 mg 1 hour before smoke inhalation and 35 mg 24 hours after smoke inhalation; n = 6) or equivalent volumes of 0.9% saline solution (n = 6). After the smoke inhalation injuries, the PaO2/FIO2 ratio declined in both groups until 40 hours after the injuries, when a trend toward improvement was noted in the group that received LAM1-3. Lung lymph flow increased in both groups until 36 hours after the smoke inhalation injuries and then significantly decreased in the group that received LAM1-3. Forty-eight hours after the smoke inhalation injuries, there was a significant decrease in the ratio of wet-dry lung weight and in preservation of the reflection coefficient in the group that received LAM1-3 (P < .05). Histopathologic examination showed no differences between the groups in the pulmonary morphology associated with smoke inhalation. A reduction in splanchnic blood flow was noted in the control group (P < .05); this reduction was attenuated by treatment with LAM1-3. The delayed pulmonary effects and improved splanchnic blood flow suggested that LAM1-3 attenuated the development of a systemically induced secondary lung injury rather than of the primary lung injury associated with smoke inhalation.     

7-硝基吲唑在烟雾吸入性肺损伤中的作用

目的 探讨神经型一氧化氮合酶（nNOS）抑制剂7-硝基吲唑（7-NI）在烟雾吸入性肺损伤中的作用。方法 40只SD雄性大鼠被随机分为正常对照组（n=8）、烟雾吸入性肺损伤模型组（n=16）和7-NI治疗组（n=16），建立烟雾吸入性肺损伤模型。7-NI治疗组在致伤后立即腹腔注射7-NI 20mg／kg（溶于2ml花生油中）；正常对照组及模型组腹腔注射2ml花生油。分别于伤后2、6、12和24h时间点监测动脉血气分析；并分批处死大鼠，取肺组织测肺含水量，制备肺组织匀浆检测超氧化物歧化酶（SOD）、过氧化氢酶（CAT）、各型一氧化氮合酶（NOS）活性及肿瘤坏死因子-α（TNF—α）和一氧化氮（NO）含量。光镜下观察肺组织病理学变化。结果 与模型组比较，7～NI治疗组各时间点动脉血氧分压均显著升高（P均〈0．05），肺组织含水量显著降低（P〈0．05），肺组织中SOD及CAT活性均明显升高（P均〈0．05），nNOS活性及NO含量均明显降低（P均〈0．05）。治疗组2h和6h肺组织中TNF—α含量均较模型组降低（P均〈0．05）。光镜下7-NI治疗组较模型组损伤程度减轻，炎性细胞浸润减少，肺间质内未见点状出血。结论 7-NI对烟雾吸人性肺损伤有较好的保护作用，可提高动脉血氧分压，减轻肺水肿程度，增加组织抗氧化能力，并减轻组织炎性细胞浸润。     

高频振荡通气及肺泡表面活性物质对吸入性损伤兔肺组织的影响

目的 比较高频振荡通气(HFOV)与HFOV联合肺泡表面活性物质(PS)对重度蒸汽吸入性肺损伤兔肺组织的保护作用.方法 将24只新西兰大白兔制成重度蒸汽吸入性肺损伤模型后,按随机数字表法分为3组,每组8只.分别给予常规机械通气(CMV)、HFOV、HFOV+气管内滴入外源性PS(100 mg/kg)治疗;通气4 h后处死动物,取肺组织观察组织病理变化,并行肺组织损伤评分.结果 肺大体标本、光镜下及电镜下均观察到HFOV后肺损伤程度较CMV明显减轻,3组中以HFOV+PS组损伤最轻,CMV组损伤最重;肺组织损伤评分也显示CMV组最高[(3.71±0.43)分],HFOV+PS组最低[(2.08±0.28)分],HFOV组居中[(2.87±0.26)分],两两比较差异均有统计学意义(P<0.05或P<0.01).结论 与CMV比较,HFOV通过减少肺组织内炎性细胞浸润及水肿液的渗出,可减轻吸入性肺损伤,且HFOV联合PS作用最明显.     

Effects of manganese superoxide dismutase, when given after inhalation injury has been established

OBJECTIVES: To determine whether treatment with manganese superoxide dismutase (MnSOD), given intravenously after inhalation injury has been established, improves oxygenation and lung fluid balance. DESIGN: Randomized, controlled intervention trial. SETTING: University research laboratory. SUBJECTS: Twenty-four chronically instrumented awake ewes with lung lymph fistulas. INTERVENTIONS: After smoke inhalation with 48 breaths of cotton smoke, the animals were assigned randomly to a control group (n = 6) or a treatment group, receiving 1000 units of MnSOD/kg (n = 6), 3000 units of MnSOD/kg (n = 6), or 9000 units of MnSOD/kg (n = 6) intravenously 1 hr after smoke inhalation. MEASUREMENTS AND MAIN RESULTS: Different from the other three groups, in the group that received 3000 units of MnSOD, cardiac output and Pao2/Fio2 ratio did not significantly decrease throughout the experimental period. Apart from higher oxygen consumption in the group receiving 3000 units of MnSOD 24 hrs after smoke inhalation (263 +/- 44 mL/min vs. 182 +/- 36 mL/min; p < 0.05), no significant differences between treatment groups and control group were observed. CONCLUSIONS: Treatment with MnSOD given after smoke inhalation seems to be less effective then pretreatment with MnSOD, which was reported in previous studies to reduce the degree of inhalation injury.     

高浓度氧对未成年大鼠肺部炎症反应的影响

目的 探讨高浓度氧对未成年大鼠肺部炎症反应的影响.方法 将40只出生21 d的SD大鼠按随机数字表法分为空气对照组及高氧暴露12、24、48、72 h组,每组8只,分别将大鼠置于空气和常压高氧箱(氧含量达92%～94%)中.于相应时间点采用放血法处死大鼠后取肺组织,并行支气管肺泡灌洗.采用硫代巴比妥酸法和比色法分别测定肺组织丙二醛(MDA)含量及髓过氧化物酶(MPO)活性;采用酶联免疫吸附法(ELISA)检测支气管肺泡灌洗液(BALF)中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)和IL-10含量;观察肺组织病理改变,并进行肺损伤评分.结果 与空气对照组比较,高氧暴露12 h肺组织MDA含量(mmol/g)即显著升高(2.24±0.43比1.57±0.31),MPO活性(U/g)于高氧暴露24 h显著升高(1.24±0.25比0.69±0.22),并均随高氧暴露时间延长逐渐增加(P<0.05或P<0.01).BALF中TNF-α、IL-6和IL-10含量于高氧暴露24 h时较空气对照组显著增加[TNF-α(ng/L):135.2±44.0比94.5±22.3,IL-6(ng/L):73.1±14.2比55.7±17.3,IL-10(ng/L):67.9±21.7比48.2±7.6,P<0.05或P<0.01];但高氧暴露48 h时较24 h时显著降低(48 h时BALF中TNF-α、IL-6、IL-10分别为105.4±17.0,54.3±17.4,50.9±6.9,均P<0.05).高氧暴露12 h时肺损伤评分(分)即较空气对照组显著升高(4.5±1.4比1.3±0.5),并随高氧暴露时间延长进一步升高(P<0.05或P<0.01).结论 高浓度氧可引起未成年大鼠肺部炎症损伤;炎症细胞因子的出现高峰均在高氧暴露24 h.     

硫化氢对急性肺损伤大鼠白细胞介素的调节

目的 研究气体信号分子硫化氢(H2S)在油酸诱导的大鼠急性肺损伤(ALI)中的作用及其在ALI中对炎症反应的调节.方法 采用鼠尾静脉缓慢注射油酸(OA,0.01 ml/kg)复制大鼠急性肺损伤模型,将SD大鼠49只随机分为三组:对照组、OA组及OA+硫氢化钠(NaHS)组.OA组和OA+NaHS组分为2 h、4 h、6 h三个观察点.对照组鼠尾静脉注射生理盐水(0.01 ml/kg),观察6 h.测定动脉血氧分压(PaO2)、肺湿干重比(W/D)、肺泡灌洗液中性粒细胞百分比(PMN%),光镜下半定量肺损伤评分(IQA),用敏感硫电极法检测血浆、肺组织匀浆H2S含量,用双抗体夹心ELISA法测定血浆、肺组织匀浆IL-6、IL-8和IL-10的含量.多组样本的均数的比较采用单因素差分析.结果 油酸鼠尾静脉注射可引起肺组织明显的形态学改变;与对照组比,OA组可见PaO2下降,W/D、PMN%、IQA增加(P＜0.01),在2 h、4 h、6 h时,血浆中H2S[对照:(36.58±6.80)μmol/L,2 h:(21.30±2.75)μmol/L,4 h:(20.63±1.26)μmol/L,6 h:(20.00±1.60)μmol/L,P＜0.01]以及肺匀浆中H2S[对照:(27.61±2.20)μmol/L,2 h:(20.67±1.37)μmol/L,4 h:(20.79±1.10)μmol/L,6 h:(18.92±0.75)μmol/L,P=0.000]均明显降低,血浆中IL-6[对照:(73.95±14.68)pg/ml,2 h:(186.70±23.85)pg/ml,4 h:(238.50±26.46)pg/ml,6 h:(215.95±25.86)pg/ml,P＜0.01]、肺匀浆中IL-6[对照:(60.58±12.91)pg/ml,2 h:(160.32±24.57)pg/ml,4 h:(195.27±46.28)pg/ml,6 h:(185.66±17.42)pg/ml,P＜0.01]均显著增加,血浆IL-8[对照:(80.69±20.42)pg/ml,2 h:(184.11±19.51)pg/ml,4 h:(286.20±53.34)pg/ml,6 h:(241.30±45.85)pg/ml,P＜0.01]、肺匀浆中IL-8[对照:(69.14±15.96)pg/ml,2 h:(174.10±20.36)pg/ml,4 h:(249.02±31.17)pg/ml,6 h:(237.74±34.18)pg/ml,P＜0.01]均显著增加,血浆IL-10[对照:(39.78±8.97)pg/ml,2 h:(111.18±11.46)pg/ml,4 h:(115.60±13.91)pg/ml,6 h: (102.41±9.93)pg/ml,P＜0.01]、肺匀浆中IL-10[对照:(71.86±14.19)pg/ml,2 h:(126.96±18.72)pg/ml,4 h:(151.88±27.61)pg/ml,6 h:(137.28±14.22)pg/ml,P＜0.01]含量均显著增加.而预先给予NaHS能减轻油酸引起的肺损伤,显著提高血浆和肺匀浆中H2S含量[4 h,血浆:(26.67±3.44)μmol/L vs(20.63±1.26)μmol/L,P=0.042;肺匀浆:(23.20±1.48)μmol/L vs(20.79±1.10)μmol/L,P=0.011;6 h,血浆:(26.98±4.93)μmol/L vs(20.00±1.60)μmol/L,P=0.022;肺匀浆:(21.43±1.79)μmol/L vs(18.92±0.75)μmol/L,P=0.016),同时血浆IL-6(185.37±21.98 pg/ml vs 238.50±26.46 pg/ml,4 h,P＜0.01;(124.22±21.84)pg/ml vs(215.95±25.86)pg/ml,6 h,P＜0.01 ]、IL-8[(199.40±34.56)pg/ml vs(286.20±53.34)pg/ml,4h,P＜0.01;(146.58±20.23)pg/ml vs(241.30±45.85)pg/ml,6 h,P＜0.01]含量明显降低,而IL-10含量增高[(154.48±18.08)pg/ml vs(115.60±13.91)pg/ml,4 h,P=0.000;(138.06±20.01)pg/ml vs(102.41±9.93)pg/ml,6 h,P=0.1300].结论 油酸诱导的大鼠ALI内源性H2S生成减少.外源性H2S通过抑制炎症因子IL-6和IL-8的表达,增加抗炎因子IL-10的表达,进而改变炎症/抗炎因子之间的比例,对油酸诱导的大鼠急性肺损伤起保护作用.     

胍丁胺对酵母多糖诱导急性肺损伤的器官保护作用

目的 探讨胍丁胺(AGM)对酵母多糖(ZYM)诱导小鼠全身炎症反应和急性肺损伤(ALI)时器官的保护作用.方法 将32只成年雄性C57BL/6小鼠按随机数字表法分为正常对照组[磷酸盐缓冲液(PBS)0.5 ml]、AGM对照组(AGM 200 mg/kg)、模型组(ZYM 500 mg/kg+ PBS 0.5 ml)、AGM治疗组(ZYM 500 mg/kg+AGM 200 mg/kg)4组,每组8只.AGM、ZYM、PBS为腹腔注射.于给药12h后采用酶联免疫吸附法(ELISA)测定血清和腹腔渗出液中肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)及一氧化氮(NO)含量;同时测定肺组织中TNF-α、IL-6、髓过氧化物酶(MPO)活性和核转录因子-kB p65(NF-kB p65)的DNA结合活性,并观察肺组织病理改变.结果 ZYM注射后12 h小鼠精神萎靡、活动减少、饮水减少;而AGM治疗组小鼠精神状况、活动、饮水均好转.AGM治疗能降低ZYM诱导的血清及腹腔渗出液的TNF-α(ng/L:252.6±32.1比421.7±76.7,295.7±78.6比592.0±84.3,均P＜0.05)、IL-6(ng/L:2 198.8±281.8比4 725.3±615.4,19 829.3±3 647.0比47 751.3±5 264.8,均P＜0.05)和NO (μmol/L:33.2±4.3比50.2±5.2,14.0±3.6比45.4±5.2,均P＜0.05)水平升高;AGM治疗也能够抑制ZYM引起的肺组织TNF-α(ng/L:245.7±39.1比378.3±67.6,P＜0.05)、IL-6 (ng/L:810.3±175.6比1 172.4±203.3,P＜0.05)、MPO活性(ng/mg:24.9±4.4比37.3±5.8,P＜0.05)和NF-kB p65(吸光度值:0.272±0.029比0.347±0.037,P＜0.05)升高.正常对照组和AGM对照组间各指标无明显差异.ZYM可导致肺组织出现严重的炎症改变,包括血管扩张、中性粒细胞浸润;AGM治疗后肺组织损伤明显减轻.结论 AGM能够缓解ZYM诱导的小鼠全身炎症反应和ALI的严重程度.