丹参对大鼠移植肝血红素氧合酶1表达的影响*

背景：器官移植前使用丹参预处理能够保护组织缺血-再灌注损伤,改善移植器官存活率。 目的：观察含丹参的冷灌注液对同种异体大鼠移植肝脏中血红素氧合酶1表达的影响,以及对供体肝脏缺血-再灌注损伤的保护作用。 方法：将SD雄性大鼠随机分成UW液组(术中使用UW液灌注保存)、丹参+UW液组(术中使用丹参+UW液灌注保存)、ZnPP预处理组(移植前24 h腹腔内注射ZnPP,术中使用丹参+UW液灌注保存),建立稳定的大鼠同种异体肝移植模型。同时取10只正常大鼠作为正常对照。 结果与结论：丹参+UW液组和UW液组血清总胆红素、谷丙转氨酶、谷草转氨酶水平明显低于ZnPP预处理组(P < 0.01)。血红素氧合酶1mRNA及其蛋白在丹参+UW液组中较UW组表达更明显,在ZnPP预处理组中表达明显受到抑制(P < 0.05)。丹参+UW液组肝脏Suzuki标准评分明显低于ZnPP预处理组及UW液组(P < 0.05)。表明丹参能上调同种异体的大鼠移植肝脏中血红素氧合酶1 mRNA及其蛋白的表达,减轻供肝缺血-再灌注损伤,保护移植大鼠肝脏。     

血红素氧合酶-1及血红素氧合酶-2在大鼠局灶性脑缺血中的意义

目的　研究血红素氧合酶 1(HO 1)及血红素氧合酶 2 (HO 2 )在局灶性脑缺血中的作用。方法　采用大鼠大脑中动脉栓塞脑缺血模型 ,对 6 6只大鼠脑缺血后不同时间点进行HO 1、HO 2免疫组化染色及病理学研究 ,并用计算机图像分析技术计算两者表达水平。结果　栓塞后 30min大鼠皮质及海马即有HO 1阳性神经元及胶质细胞的表达 ,且随着时间推移HO 1的表达逐渐增强 ,到栓塞后 12h达峰值 (P <0 0 1) ,以后逐渐下降 ,栓塞后 1周仍有HO 1表达。HO 2在正常大鼠及梗死大鼠脑组织内均有表达。栓塞后不同时间段 ,HO 2阳性神经元的数量无明显变化 (P >0 0 5 ) ,但HO 2表达呈动态变化 ,2 4h时最高 (P <0 0 1) ,以后逐渐下降。结论　脑缺血时脑内HO 1、HO 2表达的不同变化 ,是脑组织对损伤恢复重要的机制之一。HO 1修复受损的神经元和胶质细胞 ,而HO 2在于维护正常细胞的稳定     

大鼠脑出血后血肿周围脑组织血红素氧合酶-1表达与超氧化物歧化酶活力的变化

目的研究脑出血(ICH)后血肿周围脑组织血红素氧合酶1(HO1)表达、抗氧化能力的变化及其相关性。方法将动物随机分为假手术(对照)组和ICH组,采用立体定向技术将自体血注入大鼠脑基底节区制作ICH动物模型,在不同时间点断头取脑,应用免疫组化法和黄嘌呤氧化法检测ICH后不同时间大鼠血肿周围脑组织HO1的表达及超氧化物歧化酶(SOD)的活力。结果ICH6h组大鼠脑组织有少量HO1阳性细胞,12～120h组HO1阳性细胞均明显增多,48h组为峰值,与对照组比较差异有极显著性(均P<0.01);168h组仍有少量表达。ICH6h组大鼠脑组织SOD活性与对照组相比差异无显著性(P>0.05);12～120h组SOD活性均明显降低,与对照组比较差异有极显著性(均P<0.01),72h组为最低值,168h组SOD活性与对照组比较差异无显著性(P>0.05)。血肿周围脑组织HO1阳性细胞数与SOD活性呈显著负相关(r=-0.878,P<0.05)。结论大鼠ICH后血肿周围脑组织HO1表达明显增加,脑组织的抗氧化能力下降。HO1可能通过氧化途径导致脑组织损伤。     

血红素氧合酶-1与脑出血的继发性损害

自发性脑出血是指非外伤性脑实质出血,发病率高,死亡率高[1],且脑出血后患者多遗留不同程度的神经功能障碍。因此,探讨脑出血后脑组织损伤的病理生理机制对于改善脑出血病情及预后是十分必要的。大量研究表明自发性脑出血后造成的脑损伤存在多种机制[2]:早期血肿机械占位效应、     

血红素氧合酶-1在大鼠蛛网膜下腔出血后脑血管中的表达

目的探讨蛛网膜下腔出血(SAH)后脑血管中血红素氧合酶-1(HO-1)的表达变化及其与迟发性脑血管痉挛(DCV)之间的关系。方法采用大鼠枕大池二次注血法建立SAH后DCV模型,用逆转录聚合酶链反应(RT-PCR)检测基底动脉HO-1mRNA表达的变化。结果注水对照组3、5、7d基底动脉内径周长分别为(996.20±43.25)μm、(1019.05±58.16)μm和(965.25±49.98)μm,血管壁厚分别为(9.82±0.57)μm、(9.65±0.65)μm和(10.11±0.48)μm;SAH组3、5、7d基底动脉内径周长分别为(705.65±66.57)μm、(738.70±42.19)μm和(665.31±49.85)μm,血管壁厚分别为(14.41±0.51)μm、(13.25±0.63)μm和(17.43±0.55)μm。注水对照组不同时相基底动脉中无HO-1mRNA表达;SAH组注血后3、5、7d,HO-1mRNA的相对表达量分别为0.61±0.042、0.55±0.039和0.48±0.052,以注血后3d表达水平最高。结论SAH后大鼠基底动脉有HO-1mRNA的低表达,但其不能拮抗SAH后DCV的发生。     

迟发缺血预处理低温保存肾移植供体中血红素加氧酶1的表达

背景：缺血预适应延迟反应通过诱导保护性蛋白增强组织对缺血再灌注损伤的耐受能力;血红素加氧酶1参与缺血预适应延迟保护作用。迟发缺血预处理对低温保存肾脏的作用及血红素加氧酶1是否参与其中尚不清楚。目的：观察缺血预处理诱导血红素加氧酶1的迟发缺血预处理反应对低温保存肾脏移植供体的作用。方法：雄性SD大鼠随机分入5组：空白对照组、低温保存组、缺血预处理组、缺血+低温组(n=12);缺血+给药+低温组。各组大鼠均行右肾切除,预处理或假手术操作处理后24 h采用大鼠肾脏非循环离体灌注模型获取肾脏,分别于保存24,48,72 h取样。缺血+给药+低温组除上述处理外,还于原位低温灌注术前1 h接受1次血红素加氧化酶1抑制剂锡原卟啉腹腔注射。低温保存肾脏于各保存终点留取保存液,测定pH值和乳酸脱氢酶含量;切取1/2肾脏按照光镜要求制备标本送检;剩余1/2肾脏用于免疫印迹法测定血红素加氧酶1表达,比色法测定皮质Na-K-ATP酶活性、丙二醛和还原型谷胱甘肽含量;未保存肾脏仅通过免疫印迹法测定血红素加氧酶1的基础表达情况。结果与结论：迟发缺血预处理诱导了肾组织血红素加氧酶1的表达,与单纯低温保存组相比保存24,48 h后,缺血+低温组保存液pH值、乳酸脱氢酶活性降低;肾脏组织Na-K-ATP酶活性、谷胱甘肽含量增加,丙二醛含量降低;同时点预处理组肾组织光镜形态学改变稍好于单纯低温保存组。给予血红素加氧酶1抑制剂后,这种保护作用消失。提示,迟发缺血预处理延长了肾脏低温保存时限,这可能与诱导血红素加氧酶1,增加组织抗氧化能力,减轻低温保存氧应激有关。     

局灶性脑缺血时血红素氧合酶-1 mRNA的表达

目的 观测永久性脑缺血后一氧化碳限速酶一血红素氧合酶-1(HO-1)mRNA表达的变化规律。方法 在建立MCAO局灶性脑缺血模型基础上，采用半定量RT-PCR技术观察并测定脑缺血后不同时相HO-1 mRNA的相对表达量。结果脑缺血后1h即有HO-1 mRNA的表达，随时间延长而逐渐升高，12h达最高，以后逐渐下降，至7d时仍有表达。结论 脑缺血后HO-1 mRNA表达变化是缺血脑组织损伤后重要的自身恢复机制之一。     

黄芪多糖对脑出血大鼠脑组织含铁血红素氧合酶-1蛋白表达及含水量、超微结构的影响

目的 研究黄芪多糖对脑出血大鼠脑组织含铁血红素氧合酶-1(HO-1)蛋白表达及含水量、超微结构的影响.方法 139只雄性SD大鼠随机分为假手术组、脑出血组与黄芪多糖治疗组.采用Ⅶ型胶原酶诱导法制作SD大鼠脑出血模型,假手术组以等量生理盐水代替Ⅶ型胶原酶;黄芪多糖治疗组给予黄芪多糖25 mg/kg腹腔注射,每天1次,直至处死.分别于脑出血后12 h、24 h、2 d、4 d、7 d 5个时间点对各组大鼠进行神经行为学评分,测量脑组织含水量和用免疫组化法检测HO-1蛋白表达,透射电镜观察脑出血后4 d 血肿周围神经元的超微结构.结果 脑出血组与黄芪多糖治疗组大鼠脑出血后脑组织 HO-1 表达以及脑组织含水量较假手术组显著增高(均P＜0. 01);脑出血后12 h HO-1蛋白即有表达, 2 d 达高峰, 尔后逐渐下降. 黄芪多糖治疗组与脑出血组比较, HO-1表达的变化相同,但各时间点表达均高于脑出血组(P＜0.05～0.01);脑组织含水量各时间点均显著降低(P＜0.05～0.01);4 d、7 d时大鼠神经行为学评分明显减少(均P＜0.01),神经元超微结构病理改变轻.结论 黄芪多糖可促进脑出血后脑组织HO-1的表达, 这可能是其减轻脑出血后脑水肿和脑组织损伤的机制之一.     

血红素氧合酶-1/一氧化碳系统在新生大鼠缺氧缺血性脑损伤中的作用

目的 观察新生大鼠缺氧缺血性脑损伤(HIBD)后血红素氧合酶-1/一氧化碳系统(HO-1/CO)变化,探讨其在HIBD中的作用.方法 7日龄Wistar新生大鼠按随机数字表法分为假手术组(Sham组)、缺氧缺血组(HIBD组)及HO抑制剂锌原卟啉组(Znpp组),每组6只.采用实时荧光定量PCR法、硫代巴比妥酸法(TBA法)、流式细胞术(FCM)和双波长定量测定法分别检测脑组织中HO-1 mRNA的表达、丙二醛(MDA)含量、脑组织细胞凋亡率及血中CO浓度.结果 与Sham组比较,HIBD组、Znpp组HO-1 mRNA表达均增强(分别为0.166±0.042、2.289±0.333、1.839±0.322),CO浓度升高[分别为(0.460±0.009)%、(1.026±0.145)%、(0.735±0.079)%],差异有统计学意义(P＜0.05);但与HIBD组比较,Znpp组HO-1 mRNA表达明显减少,CO浓度降低,差异有统计学意义(P＜0.05).与Sham组比较,HIBD组、Znpp组MDA含量及细胞凋亡率均明显升高[MDA含量分别为(1.016±0.210)nmol/mg prot、(1.945±0.312)nmol/mg prot、(3.202±0.693)nmol/mg prot,凋亡率分别为(0.108±0.009)%、(1.412±0.307)%、(2.458±0.565)%],差异有统计学意义(P＜0.05);与HIBD组比较,Znpp组MDA含量及细胞凋亡率明显增高,差异有统计学意义(P＜0.05).结论 缺氧缺血性脑损伤后HO-1/CO系统可能在脑损伤的恢复中起到一定的保护作用.     

血清血红素氧合酶-1在脑梗死急性期的含量变化及临床意义

目的检测脑梗死患者急性期血清血红素氧合酶-1(HO-1)浓度的动态变化,探讨HO-1在脑缺血损伤中的临床意义.方法用ELISA法测定脑梗死组发病第1、3、6 d及对照组的空腹血清HO-1浓度.结果发病第1 d HO-1浓度最高,第3 d和第6 d迅速下降.发病第1d脑梗死体积越大,HO-1浓度越高,3组间HO-1浓度有显著性差异(P＜0.01).结论HO-1浓度的升高可能是机体对脑缺血损伤的防御反应,并可能在脑梗死的发病过程中具有一定的保护作用.     

Myelin basic protein induces heme oxygenase-1 in human astroglial cells.

Heme oxygenase-1 (HO-1), also known as heat-shock protein 32 (HSP-32), is induced in many cells by a large variety of stimuli. Its induction in nervous system cells following toxic and oxidative stress was suggested to play a protective role. Its presence was recently detected by immunohistochemical studies at the level of inflammatory lesions of rat experimental autoimmune encephalomyelitis. In the present study, we demonstrate that myelin basic protein (MBP) induces HO-1 in human astroglial cells, as shown by Western blots and RT-PCR. Proteolytic fragments derived from the whole MBP show a different behavior in the HO-1 induction: MBP152-167 was able to produce a light but still significant increase in HO-1 mRNA and protein levels, whereas MBP68-84 was not. The increase in HO-1 production seems to be mediated by a Ca(2+)-dependent mechanism, since MBP addition to astrocytoma cultures induced a strong and immediate increment of [Ca(2+)](i) increase; MBP152-167 elicited a delayed and less pronounced [Ca(2+)](i) increase; no [Ca(2+)](i) changes were induced following cell treatment with MBP68-84. NO pathway involvement in the induction of HO-1 by MBP was ruled out since the expression of the inducible isoform of nitric oxide synthase was not upregulated in treated cells, neither nitrite levels were modified, as demonstrated by Greiss reaction. The possible significance of HO-1 induction following MBP stimulation is discussed.     

Ammonia-induced heme oxygenase-1 expression in cultured rat astrocytes and rat brain in vivo

Ammonia is a key factor in the pathogenesis of hepatic encephalopathy (HE), which is a major complication in acute and chronic liver failure and other hyperammonemic states. The molecular mechanisms underlying ammonia neurotoxicity and the functional consequences of ammonia on gene expression in astrocytes are incompletely understood. Using cDNA array hybridization technique we identified ammonia as a trigger of heme oxygenase-1 (HO-1) mRNA levels in cultured rat astrocytes. As shown by Northern and Western blot analysis, HO-1 mRNA levels were upregulated by ammonia (0.1-5 mmol/L) after 24 h and protein expression after 72 h in astrocytes. These ammonia effects on HO-1 are probably triggered to a minor extent by ammonia-induced glutamine synthesis or by astrocyte swelling, because HO-1 expression was not inhibited by the glutamine synthetase inhibitor methionine sulfoximine (which abrogated ammonia-induced cell swelling in cultured astrocytes), and ammonia-induced HO-1 expression could only partly be mimicked by hypoosmotic astrocyte swelling. Hypoosmotic (205 mOsm/L) exposure of astrocytes led even to a decrease in HO-1 mRNA levels within 4 h, whereas hyperosmotic (405 mOsm/L) exposure increased HO-1 mRNA expression. After 24 h, hypoosmolarity slightly raised HO-1 mRNA expression. Taurine and melatonin diminished ammonia-induced HO-1 mRNA or protein expression, whereas other antioxidants (dimethylthiourea, butylated hydroxytoluene, N-acetylcysteine, and reduced glutathione) increased HO-1 mRNA levels under ammonia-free conditions. An in vivo relevance is suggested by the finding that increased HO-1 expression occurs in the brain cortex from acutely ammonia-intoxicated rats. It is concluded that ammonia-induced HO-1 expression may contribute to cerebral hyperemia in hyperammonic states.     

Astroglia overexpressing heme oxygenase-1 predispose co-cultured PC12 cells to oxidative injury

The mechanisms responsible for the progressive degeneration of dopaminergic neurons and pathologic iron deposition in the substantia nigra pars compacta of patients with Parkinson's disease (PD) remain unclear. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in the oxidative degradation of heme to ferrous iron, carbon monoxide, and biliverdin, is upregulated in affected PD astroglia and may contribute to abnormal mitochondrial iron sequestration in these cells. To determine whether glial HO-1 hyper-expression is toxic to neuronal compartments, we co-cultured dopaminergic PC12 cells atop monolayers of human (h) HO-1 transfected, sham-transfected, or non-transfected primary rat astroglia. We observed that PC12 cells grown atop hHO-1 transfected astrocytes, but not the astroglia themselves, were significantly more susceptible to dopamine (1 microM) + H(2)O(2) (1 microM)-induced death (assessed by nuclear ethidium monoazide bromide staining and anti-tyrosine hydroxylase immunofluorescence microscopy) relative to control preparations. In the experimental group, PC12 cell death was attenuated significantly by the administration of the HO inhibitor, SnMP (1.5 microM), the antioxidant, ascorbate (200 microM), or the iron chelators, deferoxamine (400 microM), and phenanthroline (100 microM). Exposure to conditioned media derived from HO-1 transfected astrocytes also augmented PC12 cell killing in response to dopamine (1 microM) + H(2)O(2) (1 microM) relative to control media. In PD brain, overexpression of HO-1 in nigral astroglia and accompanying iron liberation may facilitate the bioactivation of dopamine to neurotoxic free radical intermediates and predispose nearby neuronal constituents to oxidative damage.     

A cytoprotective role for the heme oxygenase-1/CO pathway during neural differentiation of human mesenchymal stem cells

The inducible protein heme oxygenase-1 (HO-1) catalyzes the oxidation of heme to carbon monoxide (CO) and biliverdin, which play a concerted action in cytoprotection against oxidative stress and in the modulation of cell proliferation and differentiation. Here we report that both HO-1 expression and activity can be highly increased in undifferentiated human mesenchymal stem cells (MSCs) treated with hemin, a known HO-1 inducer. However, HO-1 mRNA and protein expression gradually decrease when MSCs undergo neural differentiation in vitro, making them extremely susceptible to glutamate-mediated cytotoxicity. A time course for HO-1 revealed that this protein is markedly down-regulated after 2 days and returns to control levels 6 days after differentiation. Treatment with glutamate (250 microM) after 2 days of neural differentiation resulted in a more pronounced lactate dehydrogenase release, a marker of cell injury, compared with undifferentiated cells. Notably, cells pretreated with hemin (50 microM) or compounds that release small amounts of CO (10 microM CORM-3 and CORM-A1) rendered cells more resistant to glutamate-induced toxicity; this effect was evident in both undifferentiated and differentiated MSCs. Our findings indicate that MSCs become more vulnerable to oxidative injury during the early stages of differentiation via mechanisms that involve a temporary inhibition of HO-1 expression. Thus, overexpression of HO-1 and CO-releasing molecules could provide a possible therapeutic strategy to improve cell viability during neural differentiation in applications that use stem cell technology.     

Quercetin protects against diabetic retinopathy in rats by inducing heme oxygenase-1 expression

Quercetin is a widely-occurring flavonoid that protects against cancer, and improves memory and cardiovascular functions.However, whether quercetin exhibits therapeutic effects in diabetic retinopathy remains unclear.In this study, we established a rat model of streptozocininduced diabetic retinopathy.Seventy-two hours later, the rats were intraperitoneally administered 150 mg/kg quercetin for 16 successive weeks.Quercetin markedly increased the thickness of the retinal cell layer, increased the number of ganglion cells, and decreased the overexpression of the pro-inflammatory factors interleukin-1β, interleukin-18, interleukin-6 and tumor necrosis factor-α in the retinal tissue as well as the overexpression of high mobility group box-1 and the overactivation of the NLRP3 inflammasome.Furthermore, quercetin inhibited the overexpression of TLR4 and NF-κBp65, reduced the expression of the pro-angiogenic vascular endothelial growth factor and soluble intercellular adhesion molecule-1, and upregulated the neurotrophins brain-derived neurotrophic factor and nerve growth factor.Intraperitoneal injection of the heme oxygenase-1 inhibitor zinc protoporphyrin blocked the protective effect of quercetin.These findings suggest that quercetin exerts therapeutic effects in diabetic retinopathy possibly by inducing heme oxygenase-1 expression.This study was approved by the Animal Ethics Committee of China Medical University, China(approval No.2016 PS229K) on April 8, 2016.     

Effect of growth factors and steroid hormones on heme oxygenase and cyclin D1 expression in primary astroglial cell cultures

Astrocyte activity may be modulated by steroid hormones and GFs. This study investigates the interaction between glucocorticoids or estrogens and GFs on the expression of heme oxygenase‐1 (HO‐1) and cyclin D1 in astrocyte cultures at 14 days treated for 48 or 60 hr with dexamethasone (DEX) or 48 hr with 17β‐estradiol (E₂) alone or with GFs added only in the last 12 or 24 hr. Twelve‐ or twenty‐four‐hour epidermal growth factor (EGF) treatment significantly enhanced HO‐1 expression in astrocyte cultures pretreated for 48 hr with DEX. A highly significant increase in HO‐1 expression was obtained after the last‐12‐hr EGF treatment in 48‐hr E₂‐pretreated astrocyte cultures; this enhancement was particularly significant in 48‐hr E₂‐pretreated cultures as well as in the last‐12‐hr insulin‐treated ones pretreated for 48 hr with E_2. Sixty‐hour DEX‐alone pretreatment as well as the last‐12‐hr EGF treatment in 60‐hr DEX‐pretreated astrocyte cultures showed a significant increase of cyclin D1 expression. A significant decrease of cyclin D1 expression in the last‐12‐hr insulin‐like growth factor‐I (IGF‐1)‐treated cultures pretreated for 60 hr with DEX was observed. A highly significant enhancement in cyclin D1 expression in 14 days in vitro astrocyte cultures pretreated with E₂ alone for 48 hr and treated in the last 12 hr with IGF‐1 in 48‐hr E₂‐pretreated cultures was found. Finally, the data highlight an interactive dialogue between the growth factors and glucocorticoids or estrogens during the maturation of astroglial cells in culture that may control the HO‐1 and cyclin D1 expression as well as proliferating astroglial cells during the cell cycle. © 2014 Wiley Periodicals, Inc.