Effect of retinoic acid on oxygen-induced lung injury in the newborn rat

Oxygen-induced lung injury is believed to lead to the development of bronchopulmonary dysplasia (BPD). To determine whether retinoic acid (RA) treatment prevents the development of BPD by minimizing lung injury, we investigated the effect of RA on the histopathologic characteristics of oxygen-induced lung injury in a newborn rat model. Eighteen rat pups were divided into three groups: room air-exposed control group (n=5), oxygen-exposed placebo group (n=7), and RA-treated oxygen-exposed group (n=6). Measurement of alveolar area, quantitation of secondary crest formation, microvessel count, evaluation of alveolar septal fibrosis, and smooth muscle actin (SMA) immunostaining were performed to assess oxygen-induced changes in lung morphology. Treatment of oxygen-exposed animals with RA resulted in a significant increase in mean alveolar area; however, it had no effect on the number of secondary crests and microvessel count. The degree of fibrosis and SMA expression showed a significant decrease in RA-treated animals. We conclude that RA treatment improves alveolar structure and decreases fibrosis in the newborn rat with oxygen-induced lung injury. Extrapolating these findings to humans, we speculate that similar treatment with RA may reduce lung injury in preterm infants at risk for BPD.     

Montelukast does not protect against hyperoxia-induced inhibition of alveolarization in newborn rats

Impaired lung development has been demonstrated in neonatal animals exposed to hyperoxia. High lung cys-leukotriene levels may be a contributing factor towards the increase in oxygen toxicity. We investigated the effect of cysteinyl-leukotriene inhibition using the receptor antagonist, montelukast (MK, Singulair), on hyperoxia-induced changes in lung parenchymal structure in neonatal rat pups. Rat pups were exposed to 21% O(2) (air) or 50% O(2) (moderate hyperoxia) from days 1-14 after birth, and were administered the cys-leukotriene receptor antagonist MK (1 mg/kg/day) or normal saline from days 4-14. Somatic growth and morphometric measurements were done on day 15. There was a significant increase in bronchoalveolar lavage fluid cysteinyl-leukotriene levels (+61.9%) when animals were exposed to hyperoxia. O(2) exposure significantly decreased the specific internal surface area by 13%. There was a nonsignificant 5.8% and 19.6% increase in mean chord length and mean alveolar diameter, respectively, as well as an 8.6% decrease in lung volume to body weight ratio. Inhibition of only one arm of the arachidonic-acid cascade by MK was not sufficient to prevent these oxygen-induced changes.     

银杏叶提取物对脂多糖诱导D-半乳糖致衰老大鼠急性肺损伤的保护作用

目的　观察脂多糖 (LPS)诱导D 半乳糖 (D gal)致衰老大鼠急性肺损伤 (ALI)及银杏叶提取物 (GBE)对其是否有保护作用。方法　大鼠 2 4只随机分成两部分 ,6只为正常对照组 ;18只经腹腔注D gal复制衰老动物模型。后者再随机分成三组 :衰老对照组 (6只 ) ;LPS组 (6只 ,静脉注射LPS诱导形成ALI) ;GBE +LPS组 (6只 ,注LPS前 7天开始每天灌胃给GBE一次 ,按所含黄酮甙计算 ,8mg/kg体重 ,实验当日在给LPS前 2h再给一次GBE)。注LPS后 2h收集标本待测。结果　D gal致衰老大鼠较正常大鼠血中超氧化物歧化酶 (SOD)及肺组织Na+ K+ ATPase活性均显著降低 (P均 <0 0 5 ) ,而血中乳酸脱氢酶 (LDH)活性升高 (P <0 0 5 )。衰老大鼠注LPS后 2h已形成ALI。肺间质及肺泡中有较多炎性细胞 ;肺泡灌洗液中蛋白含量及肺通透指数增加 ;血中乳酸 (LD) ,丙二醛 (MDA) ,一氧化氮 (NO) ,内皮素 1(ET 1) ,肿瘤坏死因子 α(TNF α)含量和LDH活性以及肺组织中髓过氧化物酶 (MPO)活性 ,均显著升高 ;而血中超氧化物歧化酶活性及肺组织Na+ K+ ATPase活性均下降 (P <0 0 5 ,P <0 0 1)。预先给予GBE可显著地缓解除SOD活性外的上述其它指标的变化 (P <0 0 5 )。结论　D gal致衰老大鼠体内抗氧化能力降低。静注LPS可引起衰老大鼠明显的A     

N-乙酰半胱氨酸对大鼠肺缺血再灌注损伤的保护作用

目的探讨N-乙酰半胱氨酸(NAC)对大鼠在体肺缺血再灌注(I/R)损伤的保护作用。方法建立大鼠在体肺缺血再灌注模型,将30只SD大鼠随机分成假手术对照组,缺血再灌注组(I/R组)和N-乙酰半胱氨酸组(NAC组),NAC组缺血前1 h给予腹腔注射N-乙酰半胱氨酸200 mg/kg。再灌注2 h后摘取左肺,分别对各组进行以下检测:肺湿/干比(W/D)、超氧化物歧化酶(SOD)活力、髓过氧化物酶(MPO)活性、丙二醛(MDA)含量并进行病理学检查及肺组织损伤定量评价(IQA)。结果I/R组肺W/D和IQA显著高于假手术组(P0.01),NAC组上述指标明显降低(P0.01)。病理学结果显示三组动物肺组织结构基本正常,假手术组无充血;与NAC组比较,I/R组肺组织充血明显、白细胞浸润更严重及肺间质高度淤血水肿。I/R组MDA含量和MPO活性较假手术组明显升高(P0.01),SOD活性显著下降(P0.01)。NAC能明显减少MDA含量和降低MPO活性,提高SOD活性(P0.01)。结论N-乙酰半胱氨酸对肺缺血再灌注损伤具有保护作用,可能与其抗氧化作用和抑制中性粒细胞激活有关。     

甘草酸对急性肺损伤的保护作用

甘草酸对内毒素、卡拉胶、体外循环等因素诱发的急性肺损伤均具有良好的保护作用,可能是通过类激素样抗炎作用、抗纤维化、免疫调节以及抗氧化作用等机制发挥作用.因其疗效显著,不良反应小,甘草酸有可能成为将来临床防治急性肺损伤的策略之一.     

The role of IL-6 and IL-11 in hyperoxic injury in developing lung

We examined the cytoprotective effect of interleukin-6 (IL-6) and interleukin-11 (IL-11) during oxidant injury in neonatal lung and the regulators of cell death in vitro and in vivo after oxidant exposure. Type II cells from day 21 fetal neonatal rat lungs were treated with varying concentrations of either IL-6 or IL-11 for 24 hr prior to exposure to H(2)O(2). Three-day-old transgenic lung-specific IL-11 and IL-6 overexpressing and wild type (WT) mouse pups were exposed to hyperoxia or room air for 3 days. Type II cells exposed to either IL-6 or IL-11 prior to oxidant injury exhibited improved survival compared to controls, 67% +/- 2.6 survivals in IL-6 pretreated cells compared to 48% +/- 1.6 in control; 63% +/- 3 survivals in IL-11 pretreated cells compared to 49% +/- 2.6 in control. The number of TUNEL positive cells in hyperoxia-exposed lungs was increased compared to room air animals (27 +/- 0.9 vs. 4 +/- 0.4; mean +/- SEM; P < 0.05). In contrast, the number of TUNEL positive cells was reduced in hyperoxia-exposed lungs from IL-11 (+) mice (15.2 +/- 2.2; mean +/- SEM; P < 0.05). There was an enhanced accumulation of Bcl-2 and reduction of Bax protein in hyperoxia-exposed IL-11 (+) compared to room air-exposed mice. This was not seen in hyperoxia-exposed IL-6 (+) pups. An increase in caspase-3 was seen in hyperoxia-exposed lungs of WT pups compared to IL-11 (+) pups. IL-11 and IL-6 provide protective effects against oxidant-mediated injury in fetal type II cells and IL-11 provides protection in vivo by down-regulation of caspase-mediated cell death.     

Obesity and vitamin D deficiency: a systematic review and meta‐analysis

Over the past decade, there have been an increasing number of studies on the association between vitamin D deficiency and anthropometric state. However, we did not identify any meta‐analyses of the relationship between obesity and vitamin D deficiency in different age groups. Thus, we evaluated the association between obesity and vitamin D deficiency. We searched for observational studies published up to April 2014 in PubMed/Medline, Web of Science and Scopus databases. We performed a meta‐analysis in accordance with the random‐effects model to obtain the summary measurement (prevalence ratio, PR). Among the 29,882 articles identified, 23 met the inclusion criteria. The prevalence of vitamin D deficiency was 35% higher in obese subjects compared to the eutrophic group (PR: 1.35; 95% CI: 1.21–1.50) and 24% higher than in the overweight group (PR: 1.24; 95% CI: 1.14–1.34). These results indicate that the prevalence of vitamin D deficiency was more elevated in obese subjects. The vitamin D deficiency was associated with obesity irrespective of age, latitude, cut‐offs to define vitamin D deficiency and the Human Development Index of the study location.     

丙酮酸乙酯对急性坏死性胰腺炎大鼠肺损伤的保护作用

目的:观察丙酮酸乙酯(EP)对急性坏死性胰腺炎(ANP)肺损伤大鼠血清肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)和肺组织高迁移率族蛋白B1(HMGB1)mRNA表达的影响,探讨丙酮酸乙酯治疗急性坏死性胰腺炎肺损伤的机制.方法:逆行性胰胆管注射50 g/L牛磺胆酸钠制作ANP模型.随机分成3组,对照组、ANP组和EP治疗组(40 mg/kg,每隔6h静脉注射一次).ELISA法检测血清TNF-α和IL-1β水平;半定量逆转录聚合酶链反应(RT-PCR)法检测肺组织HMGB1 mRNA表达,并观察血氧变化及肺组织的病理变化.结果:ANP组血清TNF-α和IL-1β水平在建模后6h达高峰,12h下降,在此两时点治疗组血清TNF-α和IL-1β水平明显低于ANP组(TNF-α:131.6±29.6 ng/L vs 196.3±16.3 ng/L,65.0±16.6 ng/L vs 90.2±20.1 ng/L,P<0.05;IL-1β:194.9±26.8 ng/L vs 223.0±34.8 ng/L,105.2±24.0 ng/L vs 130.4±23.0 ng/L,P<0.05).ANP组大鼠肺组织HMGB1 mRNA表达水平在ANP后12h明显升高,至24h仍维持在高水平.治疗组肺组织HMGB1 mRNA表达水平在各时间点均明显低于ANP组(0.68±0.11 vs 0.88±0.11,0.81±0.11 vs 1.04±0.10,1.08±0.08 vs 1.33±0.15,P<0.05),且同期肺损伤比ANP组轻.治疗组PaO_2均明显高于ANP组.结论:丙酮酸乙酯能显著抑制TNF-α、IL-1β和HMGB1等早晚期炎症因子,改善低氧血症,对ANP肺损伤有明显保护作用.     

汉防己甲素预防放射性肺损伤的临床效果观察

目的观察汉防己甲素对放射性肺损伤的预防作用。方法选取2013年7月至2015年4月收治的80例非小细胞肺癌患者随机分为两组,所有患者接受三维适形或调强放疗,汉防己甲素组(Tet组)放疗期间同步口服汉防己甲素(60mg,一日三次),对照组单纯放疗。治疗后评价并比较两组放射性肺损伤发生情况。结果 Tet组2级以上放射性肺炎及放射性肺纤维化发生率均显著低于对照组(放射性肺炎16.2%vs36.8%,P=0.043;放射性肺纤维化13.5%vs 34.2%,P=0.036)。结论汉防己甲素能有效预防非小细胞肺癌患者放疗后放射性肺损伤的发生。     

巨噬细胞炎症蛋白与呼吸机所致肺损伤

呼吸机所致肺损伤（ventilator induced lung injury,VILI）是机械通气过程中的严重的并发症,也是促使患者病情加重和死亡的重要因素。巨噬细胞炎症蛋白（macrophage inflammatory protein,MIP）是近年来发现的一种参与机体炎症反应和免疫反应的趋化性细胞因子,其在VILI中的作用日益受到人们的关注,文献报道越来越多。本文就其分子结构、细胞来源、生物学活性、自身表达调节以及与VILI的关系作一综述。