Caspase inhibitor Z-VAD-FMK potentiates heat shock-induced apoptosis and HSP70 synthesis in macrophages

Caspase inhibitor Z-VAD-FMK potentiated heat shock-induced apoptosis in macrophages. Z-VAD-FMK did not activate HSP70 synthesis, but significantly increased the intensity of this process during heat shock. It cannot be excluded that caspases abolish HSP70 accumulation under these conditions. The HSP70 synthesis inhibitor quercetin potentiated DNA fragmentation in macrophages cocultured with Z-VAD-FMK after heat shock. HSP70 play an important role in the protection of macrophages from caspase-independent apoptosis.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 9, pp. 261–263, September, 2004     

Augmentation of recombinant CH50 polypeptide on the function of macrophages of mice during chemotherapy

CH50 is a Cell I- Hep Ⅱ bifunctional-domain recombinant polypeptide of human fibronectin expressed in E. colilll. This polypeptide can inhibit theinvasion and metastasis of tumor cells 1'n the[2] andactivate the anti--tumor activity of macrophages[']. Ithas been reported that this polypeptide andchemotherapeutic agent have a synergistic inhibitoryeffect on the metastasis of tumors[4J. In this study,we further investigated the effect of CH50 on thefunction of macrophages of mice during chem…     

不同临床表型COPD频繁和非频繁发作患者气道巨噬细胞的异质性

目的：比较频繁发作(frequent exacerbator,FE)和非频繁发作(infrequent exacerbator,iFE)的不同临床表型的 慢性阻塞性肺病(chronic obstructive pulmonary disease,COPD)患者的临床特征及诱导痰中巨噬细胞的异质性。方法： 分析80例慢性支气管炎(chronic bronchitis,CB)、肺气肿(emphysema,EM)、哮喘-COPD重叠(asthma-COPD overlap, ACO)表型的COPD急性发作住院患者的临床特征;采用流式细胞术检测诱导痰巨噬细胞CCL3和CD163的表达,定 量聚合酶链反应(quantitative PCR,qPCR)检测HIF-1α和Cav-1的表达。结果：FE和iFE患者在年龄,第1 s用力呼气容积 (forced expiratory volume in one second,FEV1)/用力肺活量(forced vital capacity,FVC),痰细菌阳性率,COPD评估测试 (COPD Assessment Test,CAT)评分,改良医学研究委员会(Modifi ed Medical Research Council,mMRC)评分方面的差异 有统计学意义(P<0.05);相对于iFE患者,FE患者诱导痰巨噬细胞上CCL3荧光强度明显降低(P<0.01),而CD163显著增 高(P<0.01),同时HIF-1α和Cav-1 mRNA水平也显著升高(P<0.01)。CB表型的FE患者与iFE患者之间在年龄,痰细菌阳 性率,CAT评分,mMRC评分方面的差异有统计学意义(P<0.05);相对于iFE患者,FE患者诱导痰巨噬细胞上CCL3荧 光强度轻度降低(P>0.05),而CD163显著增高(P<0.01),同时HIF-1α和Cav-1 mRNA水平也显著升高(P<0.01)。EM表型 的FE患者与iFE患者之间在年龄,病程,FEV1/FVC,痰细菌阳性率,CAT评分,mMRC评分方面的差异有统计学意义 (P<0.05);相对于iFE患者,FE患者诱导痰巨噬细胞CCL3荧光强度轻度减低(P>0.05),而CD163轻度升高(P>0.05),同 时HIF-1α水平轻度升高(P>0.05),Cav-1水平则显著增加(P<0.01)。ACO表型的FE与iFE患者所有临床特征差异均无统计 学意义,FE患者诱导痰巨噬细胞CCL3荧光强度明显低于iFE患者(P<0.01),而CD163差异无统计学意义(P>0.05),同 时HIF-1α(P<0.01)和Cav-1(P<0.05)表达也显著增加。全部FE及CB表型FE患者CCL3与HIF-1α和Cav-1均呈显著负相关, CD163仅与HIF-1α呈显著正相关;EM表型FE患者CD163与HIF-1α呈显著正相关;ACO表型FE患者CCL3与HIF-1α呈显 著负相关,而CD163与HIF-1α呈显著正相关。结论：CB,EM,ACO表型FE和iFE患者临床特征差异不一,诱导痰中替 代活化巨噬细胞(M2)在FE患者中占优势,HIF-1α可能在其极化过程中起关键作用。     

硝酸甘油、地塞米松对哮喘肺泡巨噬细胞源性一氧化氮、内皮素的影响

研究哮喘患者肺泡巨噬细胞 (AM)源性一氧化氮 (NO)、内皮素 (ET)的变化及硝酸甘油 (NTG)、地塞米松(DXM)对两者的影响及机制。对 15例轻、中度过敏性支气管哮喘发作期患者的AM(分为未干预组、DXM干预组、NTG干预组 ) ,7名健康自愿受试者的AM(未干预组 )培养 48h ,用镀铜镉还原法、放射免疫法和原位杂交法分别测定AM培养上清液中NO ,ET水平和iNOS mRNA ,ET mRNA的表达。结果发现 ,哮喘AMiNOS mRNA ,ET mRNA表达增强 ,分别导致NO ,ET水平升高 ;NTG以直接作用的方式促进AM源性NO的产生 ,反馈抑制iNOS mRNA表达并明显抑制ETmRNA的表达 ,降低ET的水平 ;DXM降低哮喘AM源性NO ,ET水平及iNOS mRNA ,ET mRNA的表达 ,尤以抑制iNOS mRNA表达和降低NO水平为甚 ,使NO ,ET处于低水平的异常状态。     

胆必清对内毒素诱导的大鼠腹腔巨噬细胞内游离钙浓度的影响

目的：探讨中药胆必清对内毒素诱导的大鼠腹腔巨噬细胞游离钙浓度的影响。方法：制备大鼠腹腔巨噬细胞并在体外进行孵育,使用荧光探针用荧光法测定钙浓度。巨噬细胞随机分为正常对照组,内毒素LPS组,小、中和大剂量中药组。结果：LPS能诱导巨噬细胞[Ca2^ ]i的升高。加入胆必清后,[Ca2^ ]i可有不同程度的降低。结论：胆必清能抑制LPS诱导的大鼠腹腔巨噬细胞内的[Ca2^ ]i升高,提示该药具有抗炎和免疫调节作用。     

The role of IL-1β during human immunodeficiency virus type 1 infection

Interleukin (IL)-1β is a key innate cytokine that is essential for immune activation and promoting the inflammatory process. However, abnormal elevation in IL-1β levels has been associated with unwanted clinical outcomes. IL-1β is the most extensively studied cytokine among the IL-1 family of cytokines and its role in pathology is well established. During the course of human immunodeficiency virus type 1 (HIV-1) infection, the level of this proinflammatory cytokine is increased in different anatomical compartments, particularly in lymphatic tissues, and this elevation is associated with disease progression. The aim of this review is to address the pathological roles play by IL-1β in the light of enhancing HIV-1 replication, driving immune cell depletion, and chronic immune activation. The role of IL-1β in HIV-1 transmission (sexually or vertically ‘from mother-to-child’) will also be discussed. Additionally, the impact of the available antiretroviral therapy regimens on the levels of IL-1β in HIV-1 treated patients is also discussed. Finally, we will provide a glance on how IL-1β could be targeted as a therapeutic strategy.     

Attenuation of diet-induced atherosclerosis in rabbits with a highly selective 15-lipoxygenase inhibitor lacking significant antioxidant properties

1. 15-Lipoxygenase (15-LO) has been implicated in the pathogenesis of atherosclerosis because of its localization in lesions and the many biological activities exhibited by its products. To provide further evidence for a role of 15-LO, the effects of PD 146176 on the development of atherosclerosis in cholesterol-fed rabbits were assessed. This novel drug is a specific inhibitor of the enzyme in vitro and lacks significant non specific antioxidant properties.
2. PD 146176 inhibited rabbit reticulocyte 15-LO through a mixed noncompetitive mode with a K_i of 197 nM. The drug had minimal effects on either copper or 2,2′-azobis(2-amidinopropane)hydrochloride (ABAP) induced oxidation of LDL except at concentrations 2 orders higher than the K_i.
3. Control New Zealand rabbits were fed a high-fat diet containing 0.25% wt./wt. cholesterol; treated animals received inhibitor in this diet (175 mg kg⁻¹, b.i.d.). Plasma concentrations of inhibitor were similar to the estimated K_i (197 nM). During the 12 week study, there were no significant differences in weight gain, haematocrit, plasma total cholesterol concentrations, or distribution of lipoprotein cholesterol.
4. The drug plasma concentrations achieved in vivo did not inhibit low-density lipoprotein (LDL) oxidation in vitro. Furthermore, LDL isolated from PD 146176-treated animals was as susceptible as that from controls to oxidation ex vivo by either copper or ABAP.
5. PD 146176 was very effective in suppressing atherogenesis, especially in the aortic arch where lesion coverage diminished from 15±4 to 0% (P<0.02); esterified cholesterol content was reduced from 2.1±0.7 to 0 μg mg⁻¹ (P<0.02) in this region. Immunostainable lipid-laden macrophages present in aortic intima of control animals were totally absent in the drug-treated group.
6. Results of these studies are consistent with a role for 15-LO in atherogenesis.

     

Lipoteichoic acid fractions from pathogenic and apathogenic Listeria species and Staphylococcus aureus induce similar amounts of macrophage-derived cytokines

Lipoteichoic acids (LTAs) of pathogenic and apathogenic Listeria species and of Staphylococcus aureus were fractionated and tested for their ability to stimulate production of cytokines (IL-1α, IL-6, TNF-α) in resident peritoneal macrophages (Mϕ) of endotoxin-resistant C3H/HeJ mice using a serum-free medium. For IL-1α and IL-6 there were no detectable differences in the ability of LTA fractions of pathogenic and apathogenic Listeria species and of Staphylococcus aureus. However, LTA-2 fractions of Staphylococcus aureus, which might be less hydrophobic than the LTA-2 fractions of the listeriae-induced lower amounts of TNF-α. Furthermore, the more lipophilic LTA-2 fractions of all LTAs employed were more potent inducers of cytokines than the less lipophilic LTA-1 fractions. The biologic effect of LTAs appears, therefore, to depend mainly on their hydrophobicity.     

Nitric oxide synthase activity is inducible in rat,but not rabbit alveolar macrophages,with a concomitant reduction in arginase activity

Alveolar macrophages were obtained by broncho-alveolar lavage of isolated rat and rabbit lungs and cultured (2.5 × 10⁶ cells/dish) for 18 h in the absence or presence of bacterial lipopolysaccharides (LPS) alone or in combination with cytokines. Thereafter, accumulation of ³H-citrulline (NO synthase activity) and ³H-ornithine (arginase activity) were determined.During incubation of rat alveolar macrophages with ³H-arginine clear amounts of ³H-citrulline and ³H-ornithine (3.8 and 4.6% of the added ³H-arginine, respectively) were formed and most of these metabolites appeared in the incubation medium (ratios extra-/intracellular of 17 and 70 for ³H-citrulline and ³H-ornithine, respectively). When rat alveolar macrophages had been cultured with LPS the formation of ³H-citrulline was increased about 30-fold and this was accompanied by a reduction in ³H-ornithine formation of about 60%. The effects of LPS were largely attenuated by dexamethasone (10 mol/1). Inhibition of NO synthase by N^G-monomethyl-l,-arginine (l-NMMA, 100 mol/1) in LPS treated alveolar macrophages reduced the formation ³H-citrulline by more than 90% and restored the ³H-ornithine formation. After culturing in the presence of LPS the ratios extra/intracellular of ³H-citrulline and ³H-ornithine were markedly enhanced and this effect was not dexamethasone sensitive. During incubation of rabbit alveolar macrophages a marked formation of ³H-ornithine (about 5.3% of the added ³H-arginine), but no significant formation of ³H-citrulline could be detected. Pretreatment with LPS tended to enhance the formation of ³H-ornithine (by 50%) without effects on ³H-citrulline. Rabbit-interferon and/or tumor necrosis factor- present together with LPS during the culture period did not result in a significant ³H-citrulline formation. Under all conditions tested, culture media of rabbit alveolar macrophages did not contain significant amounts of nitrite (less than 0.5 nmol) whereas in culture media of untreated rat alveolar macrophages 22 nmol nitrite (per 18 h) were detected, and LPS induced a 3-fold nitrite accumulation, an effect prevented by dexamethasone.In conclusion, in rabbit alveolar macrophages NO synthase activity was not detectable and could also not be induced by LPS and different cytokines, whereas in rat alveolar macrophages NO synthase was readily inducible. Alveolar macrophages of both species showed marked arginase activity. After induction of marked NO synthase activity, ornithine formation was largely reduced possibly by concomitant inhibition of arginase and/or withdrawn of arginine from arginase.     

Effect of Liposomal and Free Bisphosphonates on the IL-1β, IL-6 and TNFα Secretion from RAW 264 Cells in Vitro

Purpose. In order to evaluate the possible antiinflammatory action of bisphosphonates, the effect of the drugs on the secretion of proinflammatory cytokines (IL-l, IL-6 and TNF) from macrophages was studied. Liposomes or high concentration of extracellular calcium was used to enhance the intracellular delivery of bisphosphonates. Methods. RAW 264 cells were used as macrophage model, and they were induced with lipopolysaccharide to produce the cytokines. The cytokine concentrations in the culture supernatants were measured with time-resolved fluoroimmunoassay. Results. As a free drug, clodronate and pamidronate, but not etidronate, inhibited LPS-stimulated secretion of the cytokines from macrophage-like RAW 264 cells. Low concentrations of pamidronate, however, induced the IL-6 secretion, and the cytokine inhibitory action at the higher concentrations of pamidronate was attributed to cytotoxicity of the compound. The cytokine induction or toxic effects were not observed with clodronate or etidronate. When the drugs were encapsulated in negatively charged unilamellar liposomes, the inhibitory potency of both clodronate and etidronate enhanced by a factor of 10-20, while that of pamidronate was not increased. The complex formation of bisphosphonates with extracellular calcium, although enhancing the uptake of the compounds by macrophages, did not considerably increase their cytokine inhibitory potency. Conclusions. Bisphosphonates have inhibitory action on cytokine secretion by macrophages. The non-cytotoxic cytokine inhibition by liposome encapsulated clodronate could be beneficial in local inflammatory diseases, where the inflammation is sustained by the excessive amounts of inflammatory cytokines produced by activated macrophages.