Heme Oxygenase-1 Attenuates Contact Hypersensitivity Induced by 2,4-Dinitrofluorobenzene in Mice

Heme oxygenase (HO)-1 may have an important role in the resolution of T cell–mediated inflammation. The authors elucidated the role of the anti-inflammatory HO-1 in the pathogenesis of skin inflammation, using a mouse contact hypersensitivity (CHS) induced by 2,4-dinitrofluorobenzene (DNFB). Ear swelling was induced by challenge with DNFB, accompanied by infiltration of inflammatory cells in the challenged ear skin. DNFB challenge induced low levels of HO-1 mRNA and protein expression. Ear swelling induced by DNFB challenge was significantly reduced by topical treatment with cobalt protoporphyrin IX (CoPP), a HO-1 inducer, but exaggerated by blockage of HO-1 activity with tin protoporphyrin IX (SnPP), a HO-1 inhibitor. Similarly, the number of infiltrated cells in DNFB-challenged ear skin were reduced by CoPP but increased by SnPP. Our findings suggest that HO-1 plays an important role in CHS and is an important pharmacological target for the treatment of CHS.     

血红素氧合酶-1/一氧化碳与一氧化氮合酶/一氧化氮系统抑制球囊损伤后再狭窄的作用及其相关性研究

目的:探讨血红素氧合酶-1(HO-1) /一氧化碳(CO)系统与一氧化氮合酶(NOS) /一氧化氮(NO)系统抑制兔颈动脉球囊损伤后再狭窄的作用和相互关系。方法:家兔随机分为:对照组、胆固醇组、血红素组、卟啉锌组、精氨酸组、亚硝基组和假手术组(每组10只)。对照组予普通饮食,其余6组喂饲含1.5%胆固醇饲料,血红素组和卟啉锌组同时分别给予氯化血红素或锌原卟啉-9腹腔内注射,精氨酸组和亚硝基组同时饮水,给予L-精氨酸或亚硝基-L-精氨酸甲酯,2周后实验组行颈总动脉球囊损伤术,术后继续原方式喂养8周。结果:6组高胆固醇喂养家兔的血脂(TC、TG、LDL、ox-LDL)水平显著升高(P均0.01)。与对照组比较,胆固醇组颈动脉NO生成量、NOS活性显著降低,而CO生成量、HO-1活性、内膜面积显著增加(P均0.01)。与胆固醇组比较,血红素组HO-1活性、CO生成量显著增加,内皮素-1(ET-1)水平显著降低,内膜面积和内膜/中膜面积比减小(P均0.01);卟啉锌组HO-1活性、CO生成量明显降低,ET-1水平、内膜面积和内膜/中膜面积比显著增加(P均0.01);精氨酸组cNOS活性、NO生成量显著增加,ET-1水平,内膜面积和内膜/中膜面积比明显降低(P均0.01);亚硝基组cNOS活性、NO生成量明显降低,ET-1水平、内膜面积和内膜/中膜面积比显著增加(P均0.01)。结论:HO-1 / CO与NOS/NO系统均有抑制再狭窄的作用,两系统作用互补且相互代偿,HO-1 /CO系统通过调节和代偿NOS、NO以及下调ET-1而抑制血管损伤后再狭窄。     

诱导血红素加氧酶-1表达在器官移植中的保护作用

器官移植术中及术后移植器官的缺血再灌注损伤(ischemia-repeffusion injury,IRI)和免疫排斥反应一直困扰着外科医生.血红素加氧酶-1(heme oxygenase-1,HO-1)是血红素代谢过程中的限速酶,广泛分布于哺乳动物的各种组织细胞中.血红素在它的催化下降解代谢为一氧化碳(CO)、胆绿素和游离铁离子.HO-1在氧化应激、炎性反应、低氧和缺血等状态下均能高度表达.HO-1及其催化血红素代谢产物主要通过抗炎性反应、抗氧化反应、调节同种异体反应性T细胞的活性及增殖、抗内皮细胞凋亡、抑制内皮细胞活化等作用机制,对移植器官起到抗IRI和抗免疫排斥作用,从而增加移植器官成活率及延长其存活时间.     

Heatstroke Effect on Brain Heme Oxygenase-1 in Rats

Exposure to high environmental temperature leading to increased core body temperature above 40°C and central nervous system abnormalities such as convulsions, delirium, or coma is defined as heat stroke. Studies in humans and animals indicate that the heat shock responses of the host contribute to multiple organ injury and death during heat stroke. Heme oxygenase-1 (HO-1)—a stress-responsive enzyme that catabolizes heme into iron, carbon monoxide, and biliverdin—has an important role in the neuroprotective mechanism against ischemic stroke. Here, we investigated the role of endogenous HO-1 in heat-induced brain damage in rats. RT-PCR results revealed that levels of HO-1 mRNA peaked at 0 h after heat exposure and immunoblot analysis revealed that the maximal protein expression occurred at 1 h post-heat exposure. Subsequently, we detected the HO-1 expression in the cortical brain cells and revealed the neuronal cell morphology. In conclusion, HO-1 is a potent protective molecule against heat-induced brain damage. Manipulation of HO-1 may provide a potential therapeutic approach for heat-related diseases.     

Circulating Heme Oxygenase-1 and Complement Activation in Transplant-Associated Thrombotic Microangiopathy

Transplant-associated thrombotic microangiopathy (TA-TMA) is a severe complication in patients after hematopoietic stem cell transplantation. The pathogenesis of TA-TMA is still unclear. Previous studies showed that complement activation plays an important role in the development of TA-TMA. However, no data showed which kind of complement component triggers this process. In this study we found that heme oxygenase-1, which could induce decay-accelerating factor (DAF) and inhibit the membrane-attack complex, was significantly decreased in patients with TA-TMA. DAF levels in the TA-TMA group were in line with the levels in the myocardial infarction group but were lower than levels in the healthy, noncomplication, infection, and graft-versus-host disease groups (P < .05). Human umbilical vein endothelial cells (HUVECs) incubated with TA-TMA plasma showed lower DAF levels compared with that incubated with normal human plasma. Notably, treatment with N-acetylcysteine (NAC), a drug against oxidation, increased the level of DAF. NAC could also inhibit complement activation in HUVECs incubated with TA-TMA plasma. Taken together, we propose that NAC represents a new potential therapy for patients facing TA-TMA.     

Impaired Regulation of Synaptic Strength in Hippocampal Neurons from GluR1-Deficient Mice

Neurons of the central nervous system (CNS) exhibit a variety of forms of synaptic plasticity, including associative long-term potentiation and depression (LTP/D), homeostatic activity-dependent scaling and distance-dependent scaling. Regulation of synaptic neurotransmitter receptors is currently thought to be a common mechanism amongst many of these forms of plasticity. In fact, glutamate receptor 1 (GluR1 or GluRA) subunits containing L-α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors have been shown to be required for several forms of hippocampal LTP and a particular hippocampal-dependent learning task. Because of this importance in associative plasticity, we sought to examine the role of these receptors in other forms of synaptic plasticity in the hippocampus. To do so, we recorded from the apical dendrites of hippocampal CA1 pyramidal neurons in mice lacking the GluR1 subunit (GluR1 −/−). Here we report data from outside-out patches that indicate GluR1-containing receptors are essential to the extrasynaptic population of AMPA receptors, as this pool was nearly empty in the GluR1 −/− mice. Additionally, these receptors appear to be a significant component of the synaptic glutamate receptor pool because the amplitude of spontaneous synaptic currents recorded at the site of input and synaptic AMPA receptor currents evoked by focal glutamate uncaging were both substantially reduced in these mice. Interestingly, the impact on synaptic weight was greatest at distant synapses such that the normal distance-dependent synaptic scaling used by these cells to counter dendritic attenuation was lacking in GluR1 −/− mice. Together the data suggest that the highly regulated movement of GluR1-containing AMPA receptors between extrasynaptic and synaptic receptor pools is critically involved in establishing two functionally diverse forms of synaptic plasticity: LTP and distance-dependent scaling.     

鸟苷酸环化酶参与血红素氧化酶1对抗心肌缺血/再灌注损伤的作用

目的研究血红素氧化酶1(HO-1)在对抗心肌缺血/再灌注损伤中的作用,并探讨鸟苷酸环化酶(GC)是否参与其作用机制。方法采用离体大鼠心脏Langendorff灌流模型,观察心功能和酶学等指标。结果(1)HO-1的诱导剂高铁血红素可明显抑制缺血/再灌注心脏左室舒张末压(LV-EDP)增高,左室舒张压(LVDP)和最大左室收缩、舒张速率(±dP/dtmax)的下降;减少复氧期乳酸脱氢酶(LDH)释放,缩小心肌梗死面积(P<0.01)。(2)HO-1的抑制剂可加重缺血/再灌注心脏LVDP和±dP/dtmax下降,LDH释放和梗死面积明显高于单纯缺血/再灌注组(P<0.05)。(3)GC的抑制剂亚甲蓝可部分取消高铁血红素降低缺血/再灌注心脏LVEDP,增加LVDP和±dP/dtmax的作用,使LDH的释放和梗死面积明显增加(P<0.05)。结论诱导HO-1增加可保护缺血/再灌注心肌,其作用可能通过激动鸟苷酸环化酶途径来完成。     

Involvement of MHC-Linked Hemopoietic-Histocompatibility Genes in Allogeneic Bone Marrow Transplantation in Mice

Genes controlling resistance of irradiated mice of allogeneic hemopoietic cells were mapped within, or closely linked to the D region of MHC and were designated Hemopoietic-histocompatibility genes (Hha). Hhp genes responsible for resistance to parenteral hemopoietic cells had also previously been detected on the D-end of MHC. Hh genes are regarded as determinants of cell surface antigens (Hh antigens) phenotypically expressed, in contrast to Histocompatibility antigens (H antigens) only on blood-forming and leukemic cells. The inheritance of Hh genes is not codominant, unlike thformed on peripheral blood lymphocytes and platelets. Sixteen Tunisian families were typed with 37 patients and 108 relatives. Genetic transmission of the disease of the HLA system seemed to be independent in this study. Comparison of HLA gene frequencies (unrelated) parents of patients and a control population showed no difference, proving that there is no clear association in population between deleterious XP genes and a particular HLA gene. However, an excess of identical HLA among pairs of diseased siblings would suggest that the disease is polymorphic and a form of the XP could be linked to HLA.     

球囊损伤后血管重塑中内皮依赖性因子的作用及其相互关系

探讨球囊损伤后血管重塑中血红素氧化酶-1(HO-1)/一氧化碳(CO)与一氧化氮合酶(NOS)/一氧化氮(NO)两系统的作用及其相互关系.实验兔随机分为7组:对照组、假手术组、精氨酸组、亚硝基组、胆固醇组、血红素组和叶啉锌组.对照组喂普通饲料,其余6组喂饲含1.5%胆固醇饲料,精氨酸组和亚硝基组饮水同时给予L-精氨酸或亚硝基-L-精氨酸甲酯,血红素组和叶啉锌组同时分别予氯化血红素或锌原叶啉-9腹腔内注射,2周后各实验组行右侧颈总动脉球囊损伤术,术后续原饲养和给药8周.研究发现:与胆固醇组比较,精氨酸组cNOS活性、NO生成量显著增加,内皮素-1、NF-kB活性显著降低,内膜厚度和狭窄率显著减小[(292.65±22.48)μm,39.8%±2.51%](均P<0.01);亚硝基组上述指标变化与精氨酸组相反(均P<0.01),内膜厚度和狭窄率变化不显著[(466.49±61.34)μm,56.1%±6.81%](P>0.05);血红素组HO活性、CO生成量显著增加,内皮素-1、NF-kB活性显著降低,内膜厚度和狭窄率最小[(281.47±21.10)N,m,38.8%±2.43%](均P<0.01);叶啉锌组各指标变化与血红素组相反,内膜厚度和狭窄率最大[(698.71±58.37)μm,78.5%±6.10%](均P<0.01).结果表明NOS/NO与HO-1/CO系统在球囊损伤后血管重塑中发挥互补及代偿作用,HO-1/CO系统可能通过代偿和调节NOS/NO系统以及下调内皮素-1、NF-kB活性从而抑制血管损伤后不良重塑.     

血红素加氧酶-1重组载体的构建及在胃癌细胞中的初步研究

目的 构建人血红素加氧酶-1(heme oxygenase-1,HO-1)及其突变体的真核表达载体,观察其在胃腺癌细胞中HO-1表达和活性变化,研究HO-1活性变化的胃腺癌细胞对顺铂抗药能力的变化,为进一步研究HO-1对肿瘤细胞影响机制奠定基础.方法 根据GenBank中HO-1 cDNA序列设计引物,调取基因并克隆人pcDNA3.1(+)质粒中,构建表达人野生型HO-1与突变型HO-1(HO-1G143H)的重组质粒.脂质体介导重组质粒转染胃腺癌细胞BGC823,用RT-PCR和Western印迹法分别检测细胞中HO-1 mRNA的表达和蛋白表达水平,体外测定HO-1活性变化,应用顺铂进行体外抗药性实验.结果 酶切鉴定和测序证实,HO-1真核表达载体构建成功;转染质粒后的BGC823,HO-1的mRNA和蛋白的表达水平明显上升;转入野生型质粒的细胞HO-1活性上升,转入突变型质粒的细胞HO-1活性下降;HO-1活性下降BGC823细胞抗顺铂杀伤能力增强.结论 构建了HO-1野生型与突变型真核表达载体;将其转入胃腺癌细胞,引起了HO-1的mRNA和蛋白表达的增加和活性变化;体外实验表明,HO-1活性下降的BGC823细胞抗顺铂能力增强.     

血红素加氧酶-1对肝癌细胞细胞周期调控因子的影响

目的 观察血红素加氧酶-1(heme oxygenase 1,HO-1)对人肝癌细胞HepG2细胞周期调控因子的影响.方法 构建含有野生型和突变型HO-1基因的重组载体pcDNA3.1(+)-wtHO-1和pcDNA3.1(+)-mHO-1G143H.利用脂质体介导的方法将构建好的重组载体转染肝癌细胞系HepG2,以空载体转染作为对照组.通过G418筛选建立稳定表达野生型和突变型HO-1的HepG2肝癌细胞系.经半定量RT-PCR、Western印迹检测转染细胞系中HO-1 mRNA和蛋白的表达水平.在HO-1表达改变的稳转细胞系中,利用Western 印迹检测转染细胞系中P21、P27蛋白表达水平.结果 成功实现了野生型和突变型HO-1在HepG2细胞中的过表达;野生型和突变型HO-1过表达均能诱导抑癌基因p21和p27的表达.结论 HO-1过表达诱导抑癌基因p21和p27的表达与血红素分解产物无关.HO-1可能通过其它机制调节p21和p27的表达.     

Accelerated Skin Wound Healing in Plasminogen Activator Inhibitor-1-Deficient Mice

Components of the fibrinolytic system have been implicated in cell migratory events associated with tissue remodeling. Studies in plasminogen-deficient mice (PG(-/-)) indicated that skin wound healing is impaired, but is resolved with an additional fibrinogen deficiency. Plasminogen activator inhibitor-1 (PAI-1) expression by keratinocytes has been identified shortly after wound injury. PAI-1 expression could affect wound healing by regulating the fibrinolytic environment of the wounded area, as well as influencing events associated with cell attachment and detachment through interactions with matrix proteins. The present study directly assesses PAI-1 involvement in skin wound healing through analyses of a dermal biopsy punch model in PAI-1-deficient (PAI-1(-/-) mice. While the cellular events associated with the healing process are similar between wild-type (WT) and PAI-1(-/-) mice, the rate of wound closure is significantly accelerated in PAI-1(-/-) mice.     

Involvement of Heme Oxygenase-1 in Kaempferol-Induced Anti-Allergic Actions in RBL-2H3 Cells

Kaempferol is one of the most commonly found dietary flavonoids. The exposure to kaempferol is known to inhibit degranulation from mast cells, but the inhibitory mechanism of degranulation has not been clarified yet. In this study, we investigated the involvement of heme oxygenase (HO)-1 in the anti-allergic action of kaempferol against degranulation in rat basophilic leukemia (RBL-2H3) cells. Our results demonstrate upregulation of HO enzymatic activity after short (15 min) exposure to kaempferol, followed by the induction of HO-1 expression in protein. The involvement of HO-1 in the kaempferol-induced inhibition of degranulation was confirmed using tin protoporphyrin IX (SnPP), a HO-1 inhibitor. These findings strongly suggest that kaempferol exerts anti-allergic actions via activation of the HO-1. Etsuko Hirose and Miyoko Matsushima have contributed equally to this work.     

Heme Oxygenase-1 expression in M-CSF-polarized M2 macrophages contributes to LPS-induced IL-10 release

The shift between pro-inflammatory (M1) and anti-inflammatory (M2) states of macrophage polarization allows the resolution of inflammatory processes as well as the maintenance of a basal anti-inflammatory environment in tissues continuously exposed to harmless antigens (e.g., lung and gut). To identify markers for the anti-inflammatory state of macrophages, expression profiling was performed on human macrophages polarized by either GM-CSF or M-CSF, which lead to the generation of TNF-α and IL-12p40-producing pro-inflammatory macrophages [M1 (GM-CSF)] or IL-10-producing anti-inflammatory macrophages [M2 (M-CSF)] upon exposure to LPS, respectively. A different iron metabolism gene signature was detected in both macrophage types, with the heme regulatory molecules CD163 and Heme Oxygenase-1 (HO-1) being preferentially expressed by M2 (M-CSF) macrophages. M1-polarizing cytokines (GM-CSF, IFNγ) inhibited, while IL-4 enhanced, the M-CSF-driven HO-1 expression. In agreement with this in vitro data, HO-1 expression in metastatic melanoma was primarily detected in CD163⁺ tumor-associated macrophages, which are known to exhibit an M2-skewed polarization phenotype. In contrast to the HO-1 inhibitor tin protoporphyrin (SnPP), the administration of cobalt protoporphyrin (CoPP), a potent inducer of HO-1 resulted in increased LPS-triggered IL-10 release from M2 (M-CSF) macrophages. The data suggests that HO-1 is important for the anti-inflammatory activities of M-CSF-polarized M2 macrophages. Moreover, since M2 (M-CSF) macrophages also express higher levels of the CD163 scavenger receptor, the CD163/HO-1/IL-10 axis appears to contribute to the generation of an immunosuppressive environment within the tumor stroma.     

Characterization of Ferric Chloride-Induced Arterial Thrombosis Model of Mice and the Role of Red Blood Cells in Thrombosis Acceleration

PurposeThe ferric chloride (FeCl₃)-induced thrombosis model is widely used for thrombosis research. However, it lacks standardization with uncertainty in the exact mechanism of thrombosis. This study aimed to characterize thrombus formation in a mouse model.Materials and MethodsWe investigated thrombus formation and stability using various FeCl₃ concentrations (10%, 20%, 30%, 40%, and 50%, w/v) in carotid arteries of the Institute of Cancer Research (ICR) and C57BL/6N mice using the FeCl₃-induced thrombosis model. We also investigated thrombus histopathology using immunohistochemistry and electron microscopy.ResultsHigher FeCl₃ concentrations induced dose-dependent, faster, larger, and more stable thrombus formation in both strains of mice. However, the ICR mice showed better dose-responses in thrombus formation and stability compared to the C57BL/6N mice. Thrombi were fibrin- and platelet-rich without significant changes across FeCl₃ concentrations. However, the content of red blood cells (RBCs) increased with increasing FeCl₃ concentrations (p for trend <0.001) and inversely correlated with time to occlusion (r=-0.65, p<0.001). While platelets and fibrin were evenly distributed over the thrombus, RBCs were predominantly located near the FeCl₃ treatment area. Transmission electron microscopy showed that RBCs attached to and were surrounded by aggregates of degranulated platelets, suggesting their potential role in platelet activation.ConclusionFaster and larger thrombus formation is induced in a dose-dependent manner by a wide range of FeCl₃ concentrations, but the stable thrombus formation requires higher FeCl₃ concentrations. Mouse strain affects thrombus formation and stability. RBCs and their interaction with platelets play a key role in the acceleration of FeCl₃-induced thrombosis.     

Effects of Interleukin-17A on the Early Stages of Arterial Thrombosis in Mice

PurposeInterleukin (IL)-17A has been suggested to play a role in the growth and organization of thrombi. We examined whether IL-17A plays a role in the early stages of thrombosis and whether there are sex differences in the effects of IL-17A.Materials and MethodsWe performed a blinded, randomized, placebo-controlled study to compare time to thrombotic occlusion and sex differences therein between mice treated with IL-17A and those treated with saline using a ferric chloride-induced model. We also assessed thrombus histology, blood coagulation, and plasma levels of coagulation factors.ResultsTime to occlusion values did not differ between the IL-17A group and the control group (94.6±86.9 sec vs. 121.0±84.4 sec, p=0.238). However, it was significantly shorter in the IL-17A group of female mice (74.6±57.2 sec vs. 130.0±76.2 sec, p=0.032). In rotational thromboelastometry, the IL-17A group exhibited increased maximum clot firmness (71.3±4.5 mm vs. 66.7±4.7 mm, p=0.038) and greater amplitude at 30 min (69.7±5.2 mm vs. 64.5±5.3 mm, p=0.040) than the control group. In Western blotting, the IL-17A group showed higher levels of coagulation factor XIII (2.2±1.5 vs. 1.0±0.9, p=0.008), monocyte chemoattractant protein-1 (1.6±0.6 vs. 1.0±0.4, p=0.023), and tissue factor (1.5±0.6 vs. 1.0±0.5, p=0.003).ConclusionIL-17A plays a role in the initial st ages of arterial thrombosis in mice. Coagulation factors and monocyte chemoattractant protein-1 may be associated with IL-17A-mediated thrombosis.     

Dynamic Change and Impact of Myeloid-Derived Suppressor Cells in Allogeneic Bone Marrow Transplantation in Mice

Myeloid-derived suppressor cells (MDSCs) are a group of myeloid cells composed of hematopoietic progenitor cells, immature macrophages, dendritic cells, and granulocytes, which accumulate in inflammatory diseases and various cancers. Here, we investigated the dynamic changes and effects of MDSCs in graft-versus-host disease (GVHD) development and/or tumor relapse after syngeneic and allogeneic bone marrow transplantation (BMT). We found that adding functional MDSCs in donor graft alleviated GVHD, whereas removal of MDSCs in vivo exacerbated GVHD. After T cell-deplete BMT, MDSCs transiently accumulated in the blood and spleen of recipients without GVHD. In contrast, after T cell-replete BMT, the levels of blood MDSCs were constantly elevated in recipients with GVHD. MDSC accumulation positively correlated with the severity of GVHD. Additionally, MDSC accumulation was further increased upon tumor relapse. Although MDSCs isolated from both syngeneic and allogeneic BMT recipients inhibited T cell proliferation in response to alloantigen stimulation ex vivo, MDSCs from the recipients with GVHD showed much higher suppressive potency compared with those from recipients without GVHD. These results indicate that MDSCs can regulate the immune response in acute GVHD, and possibly tumor relapse, subsequent to allogeneic BMT.     

脑缺血再灌注后脑内血红素氧合酶-1表达的时相变化

目的 :研究局灶性脑缺血再灌注时血红素氧合酶 1(HO 1)在脑内的表达及其作用。方法 :采用梗塞大鼠大脑中动脉制备脑缺血再灌注模型 ,对 66只大鼠脑缺血及缺血再灌注后不同时间点进行HO 1免疫组化及病理学研究 ,并用计算机图像分析技术计算HO 1表达的强弱。结果 :单纯缺血 1h后皮质及海马即有HO 1阳性神经元胶质细胞的表达 ,梗塞 1h再灌 0 .5hHO 1表达与单纯缺血基本相同。随着再灌注时间的延长 ,HO 1的表达逐渐增强 ,到再灌 12h时达最高 ,以后逐渐下降 ,再灌 7天后仍有HO 1表达。HO 1主要分布在灶周皮质、梗塞皮质区、梨状皮质内的神经元及胶质细胞 ,丘脑、下丘脑、海马齿状回的神经元。结论 :局灶性脑缺血再灌注时脑内HO 1表达变化 ,是脑组织对自身损伤的重要恢复机制之一。HO 1自身具有脑保护作用并通过其下游产物CO起作用