1,25-二羟维生素D3对支气管哮喘大鼠气道炎症和肺内诱导型一氧化氮合酶的影响

目的本文探讨1,25-二羟维生素D3[1,25-dihydroxy vitmin D3,1,25-(OH)2D3]对于支气管哮喘(简称哮喘)大鼠气道炎症和肺内诱导型一氧化氮合酶(induced nitric oxide synthase,iNOS)的影响。方法50只Wistar大鼠随机分为四组:正常对照组,哮喘组,预防处理组和治疗组。用卵蛋白作为致敏原制备哮喘大鼠模型,第一组预防处理组在致敏前三天给予口服1,25-(OH)2D3,共给药3周,第二组预防组则于致敏第1天和第7天给予肌注维生素D3。治疗组则于支气管激发开始前给药处理。应用动物肺功能仪测定大鼠对于乙酰甲胆碱刺激的气道反应性,测定支气管肺泡灌洗液(BALF)细胞总数及嗜酸粒细胞计数和肺组织病理变化。检测肺组织中一氧化氮(NO)含量,iNOS活性和iNOS mRNA表达水平,用免疫组织化学染色方法检测肺组织iNOS的表达并观察iNOS在气道组织分布的改变。结果1,25-(OH)2D3预防及治疗组可减轻BALF中细胞总数及嗜酸粒细胞计数,同时降低肺组织中NO含量、iNOS活性及大鼠肺组织中iNOS mRNA的表达水平。免疫组织化学结果显示,干预组可降低哮喘大鼠气道组织中上皮细胞和巨嗜细胞中iNOS阳性。结论1,25-(OH)2D3可降低哮喘大鼠气道炎症及iNOS表达水平,提示1,25-(OH)2D3对于哮喘可能有潜在的治疗作用。     

1,25-二羟维生素D3对支气管哮喘小鼠气道重塑及基质金属蛋白酶9表达的影响

目的观察1,25-二羟维生素D3[1,25-(OH)2D3]对支气管哮喘(简称哮喘)小鼠气道重塑及其肺组织中基质金属蛋白酶9(matrix metalloprotease-9,MMP-9)表达的影响,探讨1,25-(OH)2D3在哮喘治疗中的作用。方法BALB/c小鼠随机分为对照组、哮喘组及1,25-(OH)2D3组。卵白蛋白致敏和激发建立慢性哮喘小鼠模型;HE染色观察各组气道结构改变情况;采用计算机图像分析系统评价各组气道重塑情况;采用RT-PCR法检测各组的MMP-9mRNA表达水平。结果①HE染色提示哮喘组与对照组相比出现炎性细胞浸润增多、上皮细胞脱落及平滑肌细胞层增厚等气道重塑改变,而1,25-(OH)2D3组可部分逆转上述病理改变;②1,25-(OH)2D3组的支气管内壁厚度、平滑肌层厚度和平滑肌细胞核数显著低于哮喘组,但仍高于对照组(P<0.05);③1,25-(OH)2D3组肺组织MMP-9mRNA表达水平均明显低于哮喘组,但仍高于对照组(P<0.05)。结论1,25-(OH)2D3干预可显著减轻慢性哮喘气道重塑的病理改变;并可通过部分抑制肺内MMP-9的表达来延缓气道重塑进程。     

1,25(OH)_2D_3对PM2.5在体染毒慢性阻塞性肺疾病大鼠气道炎症的作用

目的探讨1,25二羟维生素D3[1,25(OH)_2D_3]对PM2.5在体染毒慢性阻塞性肺疾病(COPD)大鼠气道炎症的作用。方法 72只雄性Wistar大鼠随机分成正常组、COPD组、1,25(OH)_2D_3+COPD组(合并组),每组24只,对三组大鼠气管滴注PM2.5染毒,每天染毒1次,连续3 d,在最后一次染毒24 h后处死动物,分析肺泡灌洗液中白细胞介素(IL)-8、IL-17、肿瘤坏死因子(TNF)-α的含量。结果 PM2.5对正常组、COPD组、合并组大鼠均产生急性毒性,且存在剂量反应关系,COPD组肺泡灌洗液中IL-8、TNF-α浓度明显高于正常组(P<0.05),经1,25(OH)_2D_3干预COPD组IL-8、TNF-α浓度低于COPD组,但仍高于正常组(P<0.05)。结论 COPD大鼠比正常大鼠对PM2.5更加易感,PM2.5可加重COPD的气道炎症。1,25(OH)_2D_3可减轻COPD气道炎症及损伤,在PM2.5染毒情况下补充1,25(OH)_2D_3对COPD的气道炎症仍具有改善作用。     

支气管哮喘小鼠模型中维生素D相关分子的表达

目的探讨维生素D相关分子在支气管哮喘（简称哮喘）小鼠模型中的表达及地塞米松的干预效果。方法用卵白蛋白作为致敏原制备小鼠哮喘模型,随机分为两组（n=6）,分别为地塞米松处理组和生理盐水处理组（对照组）,收集各组小鼠的支气管肺泡灌洗液和支气管组织,计数总细胞数和白细胞分类数,采用real—time RT-PCR技术检测支气管组织中维生素D3上调蛋白1（VDUP1）、维生素D受体（VDR）和1口羟化酶CYP27B1的mRNA表达水平。结果哮喘组支气管组织中VDUP,mRNA、VDRmRNA和CYP27B1mRNA水平分别为（2．74±0．99）、（7．06±4．05）和（3．40±2．16）,明显高于对照组（分别为1．01±0．18、1．28±0．76、1．45±1．39,P〈0．05）和地塞米松治疗组（分别为0．94±0．34、0．76±0．18、0．27±0．17,P〈0．01）。结论维生素D相关分子可能参与了哮喘的发病过程。     

老龄2型糖尿病大鼠维生素D与胰岛素抵抗的关系

目的 观察老龄2型糖尿病大鼠维生素D水平与胰岛素抵抗(IR)的关系.方法 测定老龄2型糖尿病大鼠、维生素D3处理的老龄2型糖尿病大鼠、1-α(OH)D3处理的老龄2型糖尿病大鼠和正常老龄大鼠IR、血25-(OH) D3和1,25-(OH)2D3水平.正常血糖胰岛素钳夹技术(EICT)测定各组大鼠IR,用葡萄糖输注速率(GIR)表示IR情况,25-(OH)D3和1,25-(OH)2D3水平测定用放免法.结果 老龄2型糖尿病大鼠和正常老龄大鼠相比,GIR和1,25-(OH)2D3有显著降低,25-(OH)D3无显著差异.维生素D3处理的老龄2型糖尿病大鼠与老龄2型糖尿病大鼠相比,25-(OH)D3显著升高,但1,25-(OH)2D3无显著改变.1-α羟化维生素D3处理的老龄2型糖尿病大鼠与老龄2型糖尿病大鼠相比,25-(OH)D3无明显改变,1,25-(OH)2D3增加显著.维生素D3处理的老龄2型糖尿病大鼠、1-α(OH) D3处理的老龄2型糖尿病大鼠与2型糖尿病老龄大鼠相比,IR无显著差异.结论 老年2型糖尿病大鼠中维生素D与IR无显著相关性.     

冬虫夏草及地塞米松对SD大鼠急性支气管哮喘肺组织AQP1表达的影响

目的通过观察SD大鼠急性支气管哮喘肺组织中水通道蛋白1（AQP1）的分布及表达和冬虫夏草（CS）及地塞米松（DM）对AQP1表达的影响,探讨AQP1在急性支气管哮喘发生发展中的作用。方法将SD大鼠随机分为生理盐水对照组、哮喘对照组、CS干预组（灌胃4 g/kg）、DM干预组（腹腔注射2.5 mg/kg）,干预组在激发阶段进行,2周后处死大鼠。观察肺组织病理学改变,对支气管肺泡灌洗液（BALF）的炎症细胞进行计数及分类,用ELISA法检测BALF中IL-4、INF-γ;用免疫组化、Western blot方法检测哮喘大鼠肺部AQP1的分布及表达。结果①哮喘对照组肺组织内可见弥漫的炎性渗出性改变,而CS、DM干预组炎性改变程度则较轻。②与生理盐水对照组比较,哮喘对照组BALF中细胞总数及嗜酸性粒细胞（EOS）、中性粒细胞、淋巴细胞、IL-4均升高（P〈0.01）,INF-γ降低（P〈0.05）;CS、DM干预后细胞总数及EOS、中性粒细胞、淋巴细胞、IL-4均明显下降（P〈0.05）,CS、DM组间无统计学差异（P〉0.05）。③AQP1主要分布在肺泡周围毛细血管内皮细胞、黏膜固有层的血管内皮细胞、气道黏膜上皮细胞、淋巴细胞及EOS;哮喘对照组呈强阳性表达（P〈0.01）,CS、DM干预组较哮喘对照组表达减弱,但较生理盐水对照组强（P〈0.05）,CS、DM组间AQP1表达无统计学差异（P〉0.05）。结论①AQP1在急性支气管哮喘大鼠的支气管、肺组织内及炎症细胞呈强阳性表达。②CS及DM均能抑制炎症细胞及炎症因子在肺内聚集,并对SD大鼠急性支气管哮喘肺组织AQP1的表达有显著抑制作用。     

地塞米松对哮喘大鼠Th2细胞分化的影响

目的研究糖皮质激素对哮喘大鼠肺组织Th2细胞分化的影响,探讨糖皮质激素治疗哮喘的可能机制。方法 24只SPF（无特定病原体）级SD（远交群）雄性大鼠随机分为3组,用卵清蛋白（OVA）建立哮喘模型：正常对照组、哮喘组、地塞米松组。留取支气管肺泡灌洗液（BALF）进行细胞计数及分类,采取ELISA法测定BALF中白细胞介素4（IL-4）的含量;应用免疫组化及流式细胞术测定肺组织中GATA-3（GATAbindingprotein3）的表达。结果哮喘组BALF中嗜酸性粒细胞占细胞总数百分比（EOS%）、淋巴细胞占细胞总数百分比（Lym%）、IL-4水平,显著高于正常对照组及地塞米松组（P〈0.01）;免疫组化及流式细胞术显示,哮喘组GATA-3表达显著高于正常组及地塞米松组（P〈0.01）;地塞米松组BALF中EOS%、Lym%和IL-4水平、肺组织GATA-3阳性表达与正常组比较差异无统计学意义（P〉0.05）。结论转录因子GATA-3及细胞因子IL-4的高表达,参与哮喘的病理生理过程;地塞米松可减少肺组织炎性细胞浸润,下调哮喘大鼠GATA-3、IL-4水平,提示其可抑制Th0细胞向Th2细胞分化,使Th1/Th2比例趋于平衡。     

血清1,25-双羟维生素D3水平与绝经期哮喘急性发作的相关性研究

目的探讨血清1,25-双羟维生素D3(1,25-(OH)2-VitD3)水平与绝经期哮喘急性发作的相关性。方法收集2017年1月至2018年5月于我院住院符合纳入标准的绝经期哮喘急性发作患者40例作为实验组,同期收集符合纳入标准的我院健康体检者40例作为对照组。均采集空腹血标本,实验组于入院后次日晨采集,离心并收集血清,置于-70℃冰箱保存,后用酶联免疫吸附法(ELISA)检测血清1,25-(OH)2-VitD3水平。入院当天对实验组各研究对象进行ACT量表评分并当场收回,同时收集其入院时肺功能并记录FEV_1、FEV_1%预、FEV_1%FVC值。结果实验组血清1,25-(OH)2-VitD3水平明显低于对照组(P0.05)。绝经期哮喘急性发作患者血清1,25-(OH)2-VitD3水平与其ACT量表评分、肺功能(FEV_1、FEV_1%预、FEV_1%FVC)呈正相关(P0.05)。结论绝经期哮喘急性发作患者血清1,25-(OH)2-VitD3水平明显降低。血清1,25-(OH)2-VitD3水平越低,绝经期哮喘急性发作程度越重,肺功能越差。     

1,25-（OH）2D3对大鼠系膜细胞增殖的影响及机制探讨

目的探讨1,25-二羟基维生素D3[12,5-（OH）2D3]对大鼠肾小球系膜细胞（MC）增殖的影响及机制,为其临床应用提供依据。方法将体外培养的对数生长期大鼠MC分为对照组和观察组。观察组采用1,25-（OH）2D3（浓度为10-8mol/L）干预,对照组不干预。采用四甲基偶氮唑蓝（MTT）比色法检测细胞增殖情况,流式细胞仪检测细胞周期,免疫荧光染色法检测蛋白激酶（Akt）/哺乳动物雷帕霉素靶蛋白（mTOR）表达。结果与对照组比较,观察组MC增殖受抑,细胞周期阻滞于G1期;Akt、mTOR蛋白表达降低,P均〈0.05。结论 1,25-（OH）2D3可抑制大鼠肾小球MC增殖,其作用机制可能为抑制磷脂酰肌醇-3激酶/Akt/mTOR信号传导通路。     

PTEN在支气管哮喘大鼠气道炎症中的作用

目的探讨PTEN在支气管哮喘（简称哮喘）人鼠气道炎症中的作用。方法20只SPF级雄性SD大鼠随机分为2组。对照组和哮喘组。以卵清白蛋白致敏激发法复制大鼠哮喘模型,每只大鼠左肺留取肺组织,右肺进行支气管肺泡灌洗歼留取支气管肺泡灌洗液（BALF）。对BALF进行细胞分类计数;应用双抗体夹心酶联免疫吸附试验（Sandwich ELISA）法测定BALF中IL-4、IL-12浓度;采用免疫组织化学法和Western blot法测定PTEN蛋白的表达和量的变化。结果①BALF IL-4的浓度哮喘组显著高于对照组,BALF中IL-12的浓度哮喘组屁著低于对照组（P值均〈0．01）;②免疫组织化学显示PTEN蛋白主要表达细胞是支气管上皮细胞,Western blot法显示哮喘组支气管PTEN蛋白的表达显著低于对照组（P〈0．01）;③支气管上皮细胞PTEN蛋白表达量分别与BALF中的IL-4浓度呈显著负相关,与BALF中的IL—12浓度呈显著正相关。结论哮喘大鼠PTEN蛋白表达明显减少,它能减少Th2因子的表达,可能与哮喘大鼠气道炎症中Th1／Th2平衡密切相关。     

1,25-二羟维生素D3对慢性阻塞性肺疾病大鼠气道炎症的作用与机制

目的 研究1,25-二羟维生素D3[1,25(OH)2D3]对慢性阻塞性肺疾病(COPD)气道炎症的作用与机制.方法 雄性Wistar大鼠30只,分为对照组(A组)、COPD组(B组)和1,25(OH)2D3+COPD组(C组),每组10只,用熏香烟加气管注内毒素法建立大鼠COPD模型,在C组腹腔注射1,25(OH)2...     

1,25-Dihydroxyvitamin D3 prevented allergic asthma in a rat model by suppressing the expression of inducible nitric oxide synthase

The active form of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] regulates calcium homeostasis, immunity, and other physiological processes while its effect in T-helper lymphocyte type 2 models is not very clear. The prevention effect of 1,25(OH)2D3 for allergic asthma in a rat asthma model was investigated. Healthy Wistar rats were randomly divided into four groups: control group, asthma group, drug prevention group, and treatment group. Asthma was induced in rats by sensitization and challenges with ovalbumin (OVA). The drug prevention group and treatment group were given 1,25(OH)2D3 or vitamin D3 on different schedules. The effects of 1,25(OH)2D3 on the development of asthma were analyzed. The airway hyperresponsiveness, the inflammatory cell infiltration in bronchoalveolar lavage (BAL) fluid, and histological changes of lung cells were examined. Nitric oxide production and the expression and activity of induced nitric oxide synthase (iNOS) in the lungs were examined also. Our study showed that 1,25(OH)2D3 reduced the airway inflammatory response in BAL. The concentration of NO and the activity and expression of iNOS in the lungs were decreased in the 1,25(OH)2D3 prevention and treatment groups. The expression of iNOS mRNA and protein levels were dose-dependently attenuated in the presence of 10(-13)-10(-8) mol/L of 1,25(OH)2D3 in alveolar macrophage culture. These findings collectively indicated that 1,25(OH)2D3 lowered many symptoms of inflammatory responses and decreased the expression of iNOS in OVA-induced experimental asthma. 1,25(OH)2D3 could be used as a new therapeutic agent in the treatment of asthma.     

支气管哮喘小鼠模型中维生素D相关分子的表达

目的 探讨维生素D相关分子在支气管哮喘(简称哮喘)小鼠模型中的表达及地塞米松的干预效果.方法 用卵白蛋白作为致敏原制备小鼠哮喘模型,随机分为两组(n=6),分别为地塞米松处理组和生理盐水处理组(对照组),收集各组小鼠的支气管肺泡灌洗液和支气管组织,计数总细胞数和白细胞分类数,采用real-time RT-PCR技术检测支气管组织中维生素D3上调蛋白1(VDUP1)、维生素D受体(VDR)和1α羟化酶CYP27B1的mRNA表达水平.结果 哮喘组支气管组织中VDUP1mRNA、VDRmRNA和CYP27 B1mRNA水平分别为(2.74±0.99)、(7.06±4.05)和(3.40±2.16),明显高于对照组(分别为1.01±0.18、1.28±0.76、1.45±1.39,P＜0.05)和地塞米松治疗组(分别为0.94±0.34、0.76±0.18、0.27±0.17,P＜0.01).结论 维生素D相关分子可能参与了哮喘的发病过程.     

1 alpha,25-Dihydroxycholecalciferol reduces rejection and improves survival in rat liver allografts.

Vitamin D(3) affects the immuno response and improves experimental autoimmune diseases. We investigated the effect of 1,25-dihydroxycholecalciferol (1,25[OH](2)D(3)) Rocaltrol as a single immunosuppressive agent and in combination with low-dose cyclosporin A (CsA) in vascularized liver allografts in rats in a high-responder strain combination (ACI-->Lewis). Recipients were placed on a low-calcium diet 7 days before transplantation and were treated with 0.1 or 1 microg/kg/d 1,25(OH)(2)D(3) intraperitoneally beginning 3 days before transplantation. Treatment combining 1,25(OH)(2)D(3) with CsA (2 mg/kg/d) was also tested. Graft function and survival, histologic rejection, and concentrations of interleukin (IL)-2, -4, -10, and -12 in serum and in grafts were measured. 1,25(OH)(2)D(3) increased allograft survival in a dose-dependent manner when compared with controls (P <.05 for both groups). Serum bilirubin, aspartate transaminase (AST), and lactate dehydrogenase (LDH) activities were significantly lower in 1,25(OH)(2)D(3)-treated animals. Vitamin D reduced the concentration of IL-2 and IL-12 in serum and in grafts, and increased IL-4 and IL-10 in the grafts. The rejection activity index 10 days after transplantation was significantly lower in low- and high-dose 1,25(OH)(2)D(3)-treated rats compared with vehicle-treated controls (P <.0001 for both groups). The combination of either low-dose or high-dose vitamin D(3) and CsA prolonged graft survival when compared with low-dose CsA only (P <.05 for both groups). After 3 weeks, hypercalcemia developed in high-dose 1,25(OH)(2)D(3)-treated rats. It is concluded that 1,25(OH)(2)D(3) prolongs survival of liver allografts in rats by decreasing the severity of acute rejection. Analogues of vitamin D with fewer hypercalcemic effects may have potential as immunosuppressive drugs in liver transplantation.     

Extrarenal production of calcitriol in normal and uremic humans

We have previously reported low serum levels of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] and increased 1,25-(OH)2D3 production after the administration of 25-hydryoxyvitamin D (25OHD) to anephric humans. Since normal alveolar macrophages are known to synthesize 1,25-(OH)2D3 when stimulated with gamma-interferon or lipopolysaccharide, we determined whether macrophages derived from peripheral blood monocytes could be an extrarenal source of 1,25-(OH)2D3. Our results demonstrated that macrophages from normal individuals synthesize 1,25-(OH)2D3. The apparent Km for 25OHD3 was 6.6 +/- 0.5 nM and the maximum velocity was 47.4 +/- 13.7 fmol 1,25-(OH)2D3/h.microgram DNA. The activity of this enzyme was reduced 37.2 +/- 3.1% by physiological concentrations (96 pmol/L) of 1,25-(OH)2D3 in the incubation medium. Normal macrophages further hydroxylated 1,25-(OH)2D3 to more polar metabolites, and this catabolic activity was significantly enhanced by physiological concentrations of 1,25-(OH)2D3. In chronic renal failure, peripheral macrophages exhibited an enhanced 1 alpha-hydroxylase activity (8.2 +/- 0.8 vs. 4.2 +/- 0.5 fmol 1,25-(OH)2D3/microgram DNA.h in controls) and a decreased capacity to degrade 1,25-(OH)2D3. Exogenous 1,25-(OH)2D3, in physiological concentrations, reduced 1,25-(OH)2D3 synthesis to a degree (23.6 +/- 8.5%) comparable to that observed in normal cells. 1,25-(OH)2D3 production by macrophages did not correlate with the severity of hyperparathyroidism. Moreover, human PTH-(1-34) in supraphysiological concentrations (20,000 and 100,000 ng/L) did not stimulate the 1 alpha-hydroxylase activity of macrophages from either normal or uremic subjects. These results demonstrate that 1) normal peripheral macrophages metabolize 25OHD3 and 1,25-(OH)2D3; 2) macrophages in uremia display higher rates of 1,25-(OH)2D3 synthesis and lower rates of catabolism than normal macrophages; and 3) 1,25-(OH)2D3 deficiency, but not hyperparathyroidism, may play a role in the stimulation of 1,25-(OH)2D3 production by macrophages in chronic renal failure.     

25-Hydroxyvitamin D3 metabolism by lipopolysaccharide-stimulated normal human macrophages

Cultured normal human pulmonary alveolar macrophages and peripheral blood monocyte-derived macrophages were studied for their capacity to metabolize [3H]25-hydroxyvitamin D3 (25OHD3). Incubation of macrophages with bacterial lipopolysaccharide (LPS) resulted in the conversion of [3H]25OHD3 to a more polar vitamin D3 metabolite (up to 15 pmol/10(6) cells). Untreated macrophages did not synthesize this metabolite. Several findings suggested that the metabolite was the biologically active form of vitamin D3, namely 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. (1) The metabolite comigrated with chemically synthesized 1,25-(OH)2D3 on four different high performance liquid chromatographic systems. (2) The metabolite had the same affinity for the chick intestinal 1,25-(OH)2D3 receptor as authentic 1,25-(OH)2D3. (3) The biological activity of the macrophage metabolite in vivo (stimulation of intestinal calcium absorption and bone calcium mobilization in rachitic chicks) was identical to the activity of chemically synthesized 1,25-(OH)2D3. The LPS-stimulated synthesis of the 1,25-(OH)2D3-like compound by macrophages was dose dependent in a linear fashion; a half-maximal response was typically found with 100-200 ng LPS/10(6) cells. Polymyxin B abolished the effects of LPS on 25OHD3 metabolism in macrophages. Our data suggest that LPS-stimulated macrophages can modulate, on a local level, the function of 1,25-(OH)2D3-responsive cells by releasing the 1,25-(OH)2D3-like metabolite.     

Potentiation of the macrophage 25-hydroxyvitamin D-1-hydroxylation reaction by human tuberculous pleural effusion fluid

1,25-Dihydroxyvitamin D [1,25-(OH)2D] is classically viewed as a steroid hormone of renal origin that regulates mammalian and avian mineral ion homeostasis. More recently, 1,25-(OH)2D has been shown to be produced by and act on human inflammatory cells in vitro, suggesting that the hormone may be an important modulator of the host immune response. We have recently detected high concentrations of 1,25-(OH)2D in the pleural fluid (PF) of patients with tuberculous pleuritis. Working on the hypothesis that tuberculous PF contained a soluble cytokine which stimulated 1,25-(OH)2D production by tissue (pleura)-based macrophages, we examined the potential for PF from five patients with tuberculous pleuritis to potentiate 1,25-(OH)2D synthesis by heterologous pulmonary alveolar macrophages (PAM) from patients with sarcoidosis; PAM from patients with active pulmonary sarcoidosis constitutively express a 25-hydroxyvitamin D3-1-hydroxylation reaction in vitro. We demonstrated that tuberculous PF had a concentration-dependent potentiating effect on PAM 1,25-(OH)2D synthesis. The potentiating activity was positively correlated to the interferon-gamma (IFN gamma) concentration of the PF (r = 0.98; P less than 0.01) and was inhibited by 49-89% after coincubation with anti-IFN gamma monoclonal antibody (1:20,000-1:200 dilution). These data suggest that IFN gamma may be an important peripleural regulator of macrophage 1,25-(OH)2D synthesis in patients with tuberculous pleuritis and a high pleural fluid 1,25-(OH)2D concentration.     

Bleomycin-induced lung injury in the rabbit. Analysis and correlation of bronchoalveolar lavage, morphometrics, and fibroblast stimulating activity

We have used a rabbit model of bleomycin-induced lung injury to evaluate the chronological changes in the bronchoalveolar lavage fluid (BALF) constituents. The correlation of these changes with morphologic alterations and measured soluble mediators of fibrosis has also been assessed. Three groups of 8 treated and 8 control New Zealand white rabbits received 10 U/kg bleomycin in normal saline, or equal volumes of saline intratracheally. The animals underwent bronchoalveolar lavage with a balloon tipped catheter localized to the right lower lobe at 3, 8, or 12 wk. Total cell counts and differentials were performed on the BALF. The lungs were examined histologically for inflammatory cells in the interstitium, alveoli, and airways by morphometric techniques. The lungs were also assayed for total hydroxyproline content. Bronchoalveolar lavage fluid supernatants and supernatants from lavaged macrophages cultured for 24 h were assayed for fibroblast stimulating activity (FSA) by 3H-thymidine incorporation into rabbit lung fibroblasts. There was a significant increase in macrophages and neutrophils in the BALF at 3 wk only, although the elevation of macrophages was sustained for longer than that of neutrophils. The numbers of BALF macrophages correlated with the morphometric assessment of the number of intra-alveolar macrophages (p less than 0.001) and interstitial mononuclear cells (p less than 0.001), as well as the extent of airway inflammation (p less than 0.001). The numbers of BALF neutrophils correlated with morphometrically assessed alveolar (p less than 0.01) and interstitial neutrophils (p less than 0.01) but not with any airway inflammation scores.(ABSTRACT TRUNCATED AT 250 WORDS)     

Activation and fusion induced by 1 alpha,25-dihydroxyvitamin D3 and their relation in alveolar macrophages.

1 alpha,25-Dihydroxyvitamin D3 [1 alpha,25-(OH)2D3] induces fusion of murine alveolar macrophages. This effect was observed in growth medium containing 5% human serum but not in the medium with 5% fetal bovine serum. Unlike 1 alpha,25-(OH)2D3, bacterial lipopolysaccharides (LPS) did not induce fusion of alveolar macrophages. However, both 1 alpha,25-(OH)2D3 and LPS activated alveolar macrophages, as measured by glucose consumption, increase in Fc receptors, and induction of cytotoxicity. The number of Fc receptors on the surface of multinucleated giant cells induced by 1 alpha,25-(OH)2D3 was much smaller than that on the surface of mononuclear macrophages treated with the hormone. These results indicate that 1 alpha,25-(OH)2D3 induces both fusion and activation of alveolar macrophages, whereas LPS elicits activation only.