ICAM-1, intercellular adhesion molecule-1

ICAM - 1, 细胞间粘附分子 - 1
  • 文章类型: Journal Article
    未经证实:神经系统并发症严重影响心脏骤停体外心肺复苏(ECPR)患者的生存率和生活质量。这项研究旨在重新利用选择性低温脑灌注(SHCP)作为保护这些患者大脑的新方法。
    未经授权:大鼠被随机分配到假,ECPR,和SHCP联合ECPR(CP-ECPR)组。在ECPR小组中,在窒息心脏骤停后6分钟通过体外膜氧合进行循环复苏。监测生命体征3小时,身体和大脑温度保持在正常水平。在CP-ECPR组中,作为脑灌注的右颈动脉导管插入术与体外膜氧合装置连接,以实现选择性脑冷却(26-28°C)。评估脑损伤的血清标志物和海马的病理形态学变化。在ECPR和CP-ECPR组中,三个生物重复进一步接受RNA测序。检测脑组织和血清中的小胶质细胞活化和炎性细胞因子。
    UNASSIGNED:SHCP迅速降低脑靶向温度并显著减轻神经损伤。从脑损伤血清生物标志物水平的降低可以明显看出这一点,较低的病理评分,在CP-ECPR组中海马中存活更多的神经元。此外,根据京都基因百科全书和基因组通路分析,更多的炎症反应差异表达基因在功能上进行了聚类.并且SHCP降低了小胶质细胞的活化和促炎介质的释放。
    UNASSIGNED:我们的初步数据表明,SHCP可能作为一种潜在的治疗方法,通过下调ECPR患者的神经炎症来减轻脑损伤。
    UNASSIGNED: Neurologic complications seriously affect the survival rate and quality of life in patients with extracorporeal cardiopulmonary resuscitation (ECPR) undergoing cardiac arrest. This study aimed to repurpose selective hypothermic cerebral perfusion (SHCP) as a novel approach to protect the brains of these patients.
    UNASSIGNED: Rats were randomly allocated to Sham, ECPR, and SHCP combined ECPR (CP-ECPR) groups. In the ECPR group, circulatory resuscitation was performed at 6 minutes after asphyxial cardiac arrest by extracorporeal membrane oxygenation. The vital signs were monitored for 3 hours, and body and brain temperatures were maintained at the normal level. In the CP-ECPR group, the right carotid artery catheterization serving as cerebral perfusion was connected with the extracorporeal membrane oxygenation device to achieve selective brain cooling (26-28 °C). Serum markers of brain injury and pathomorphologic changes in the hippocampus were evaluated. Three biological replicates further received RNA sequencing in ECPR and CP-ECPR groups. Microglia activation and inflammatory cytokines in brain tissues and serum were detected.
    UNASSIGNED: SHCP rapidly reduced the brain-targeted temperature and significantly alleviated nerve injury. This was evident from the reduced brain injury serum biomarker levels, lower pathologic scores, and more surviving neurons in the hippocampus in the CP-ECPR group. Furthermore, more differentially expressed genes for inflammatory responses were clustered functionally according to Kyoto Encyclopedia of Genes and Genomes pathway analysis. And SHCP reduced microglia activation and the release of proinflammatory mediators.
    UNASSIGNED: Our preliminary data indicate that SHCP may serve as a potential therapy to attenuate brain injury via downregulation of neuroinflammation in patients with ECPR.
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  • 文章类型: Journal Article
    糖尿病肾病(DN)是糖尿病的严重并发症,是终末期肾病的主要病因,这给全世界的人类社会造成了严重的健康问题和巨大的经济负担。常规战略,如肾素-血管紧张素-醛固酮系统阻断,血糖水平控制,和减轻体重,在许多DN管理的临床实践中,可能无法获得令人满意的结果。值得注意的是,由于多目标函数,中药作为DN治疗的主要或替代疗法具有很好的临床益处。越来越多的研究强调确定中药的生物活性化合物和肾脏保护作用的分子机制。参与糖/脂代谢调节的信号通路,抗氧化,抗炎,抗纤维化,足细胞保护已被确定为重要的作用机制。在这里,在回顾临床试验结果后,我们总结了中药及其生物活性成分在治疗和管理DN中的临床疗效,系统评价,和荟萃分析,对动物和细胞实验中报道的相关潜在机制和分子靶标进行了彻底讨论。我们旨在全面了解中药对DN的保护作用。
    Diabetic nephropathy (DN) has been recognized as a severe complication of diabetes mellitus and a dominant pathogeny of end-stage kidney disease, which causes serious health problems and great financial burden to human society worldwide. Conventional strategies, such as renin-angiotensin-aldosterone system blockade, blood glucose level control, and bodyweight reduction, may not achieve satisfactory outcomes in many clinical practices for DN management. Notably, due to the multi-target function, Chinese medicine possesses promising clinical benefits as primary or alternative therapies for DN treatment. Increasing studies have emphasized identifying bioactive compounds and molecular mechanisms of reno-protective effects of Chinese medicines. Signaling pathways involved in glucose/lipid metabolism regulation, antioxidation, anti-inflammation, anti-fibrosis, and podocyte protection have been identified as crucial mechanisms of action. Herein, we summarize the clinical efficacies of Chinese medicines and their bioactive components in treating and managing DN after reviewing the results demonstrated in clinical trials, systematic reviews, and meta-analyses, with a thorough discussion on the relative underlying mechanisms and molecular targets reported in animal and cellular experiments. We aim to provide comprehensive insights into the protective effects of Chinese medicines against DN.
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  • 文章类型: Journal Article
    血脑屏障(BBB)严格控制血液和大脑之间的物质交换,并严重限制全身给药的大脑渗透,导致脑部疾病的药物治疗无效。然而,在脑部疾病的发生和发展过程中,BBB改变不可避免地演变。在这次审查中,我们专注于基于BBB进化设计的纳米级脑靶向药物递送策略以及包括阿尔茨海默病在内的各种脑疾病的相关应用,帕金森病,癫痫,中风,创伤性脑损伤和脑肿瘤。优化BBB杂交和非全身给药途径的小分子研究进展(例如,本综述不包括BBB旁路的鼻内治疗)。
    Blood-brain barrier (BBB) strictly controls matter exchange between blood and brain, and severely limits brain penetration of systemically administered drugs, resulting in ineffective drug therapy of brain diseases. However, during the onset and progression of brain diseases, BBB alterations evolve inevitably. In this review, we focus on nanoscale brain-targeting drug delivery strategies designed based on BBB evolutions and related applications in various brain diseases including Alzheimer\'s disease, Parkinson\'s disease, epilepsy, stroke, traumatic brain injury and brain tumor. The advances on optimization of small molecules for BBB crossing and non-systemic administration routes (e.g., intranasal treatment) for BBB bypassing are not included in this review.
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  • 文章类型: Journal Article
    小干扰RNA(siRNA)的使用一直在研究中,用于治疗几种未满足的医疗需求。例如包括急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS),其中可实施siRNA以在mRNA水平上修饰促炎细胞因子和趋化因子的表达。清晰的解剖结构,可访问性,和相对较低的酶活性使肺成为局部siRNA治疗的良好靶标。然而,由于裸siRNA的特性,siRNA治疗剂向靶细胞的低效递送阻碍了siRNA的临床翻译。因此,本综述将重点介绍在ALI/ARDS的siRNA治疗药物进入临床之前,可使用的各种给药系统和需要克服的不同障碍,以开发用于人类的稳定可吸入siRNA制剂.
    The use of small interfering RNAs (siRNAs) has been under investigation for the treatment of several unmet medical needs, including acute lung injury/acute respiratory distress syndrome (ALI/ARDS) wherein siRNA may be implemented to modify the expression of pro-inflammatory cytokines and chemokines at the mRNA level. The properties such as clear anatomy, accessibility, and relatively low enzyme activity make the lung a good target for local siRNA therapy. However, the translation of siRNA is restricted by the inefficient delivery of siRNA therapeutics to the target cells due to the properties of naked siRNA. Thus, this review will focus on the various delivery systems that can be used and the different barriers that need to be surmounted for the development of stable inhalable siRNA formulations for human use before siRNA therapeutics for ALI/ARDS become available in the clinic.
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  • 文章类型: Journal Article
    缺血性中风是一种脑血管疾病,通常由大脑的血液供应中断引起。缺血会引发级联反应,由大脑受损区域的多个生化事件组成,缺血级联最终导致细胞死亡和脑梗塞。已经进行了针对级联反应的不同阶段的广泛研究,目的是治愈缺血性中风。然而,基于抗栓治疗和神经保护治疗的传统治疗方法因其安全性和治疗效果不佳而受到很大限制。纳米药物为治疗中风提供了新的可能性,因为它们可以改善药物在体内的药代动力学行为,在目标部位实现有效的药物积累,提高治疗效果,同时减少副作用。在这次审查中,我们全面描述了中风的病理生理学,传统的治疗策略和新兴的纳米药物,总结纳米药物运输到病变的障碍和方法,并说明纳米医学治疗缺血性中风的最新进展,以期为脑缺血的治疗提供新的可行路径。
    Ischemic stroke is a cerebrovascular disease normally caused by interrupted blood supply to the brain. Ischemia would initiate the cascade reaction consisted of multiple biochemical events in the damaged areas of the brain, where the ischemic cascade eventually leads to cell death and brain infarction. Extensive researches focusing on different stages of the cascade reaction have been conducted with the aim of curing ischemic stroke. However, traditional treatment methods based on antithrombotic therapy and neuroprotective therapy are greatly limited for their poor safety and treatment efficacy. Nanomedicine provides new possibilities for treating stroke as they could improve the pharmacokinetic behavior of drugs in vivo, achieve effective drug accumulation at the target site, enhance the therapeutic effect and meanwhile reduce the side effect. In this review, we comprehensively describe the pathophysiology of stroke, traditional treatment strategies and emerging nanomedicines, summarize the barriers and methods for transporting nanomedicine to the lesions, and illustrate the latest progress of nanomedicine in treating ischemic stroke, with a view to providing a new feasible path for the treatment of cerebral ischemia.
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  • 文章类型: Journal Article
    急性呼吸窘迫综合征(ARDS)的特征是严重的炎症和肺部气血屏障的破坏,导致不可逆和实质性的呼吸功能损害。2019年冠状病毒病(COVID-19)患者遇到了ARDS的高风险,强调开发有效疗法的紧迫性。然而,由于药代动力学不佳,仍然缺乏治疗ARDS的适当药物,非特异性副作用,无法克服肺屏障,和异质性管理不足。在ARDS的病理环境中增加的肺通透性可能有助于纳米颗粒介导的被动靶向递送。纳米医学在解决ARDS药物治疗困境方面表现出独特的优势,可以解决传统抗炎或抗氧化药物治疗的缺点和局限性。通过被动,活跃,或物理化学靶向,纳米载体可以与肺上皮/内皮和炎症细胞相互作用,以逆转异常变化并恢复肺环境的稳态,从而显示出良好的治疗活性和降低的毒性。本文综述了纳米医学在临床前ARDS治疗中的最新应用,强调肺部炎症的靶向治疗策略,展示了创新的药物输送系统,并为加强纳米医学治疗的治疗效果提供了启示。
    Acute respiratory distress syndrome (ARDS) is characterized by the severe inflammation and destruction of the lung air-blood barrier, leading to irreversible and substantial respiratory function damage. Patients with coronavirus disease 2019 (COVID-19) have been encountered with a high risk of ARDS, underscoring the urgency for exploiting effective therapy. However, proper medications for ARDS are still lacking due to poor pharmacokinetics, non-specific side effects, inability to surmount pulmonary barrier, and inadequate management of heterogeneity. The increased lung permeability in the pathological environment of ARDS may contribute to nanoparticle-mediated passive targeting delivery. Nanomedicine has demonstrated unique advantages in solving the dilemma of ARDS drug therapy, which can address the shortcomings and limitations of traditional anti-inflammatory or antioxidant drug treatment. Through passive, active, or physicochemical targeting, nanocarriers can interact with lung epithelium/endothelium and inflammatory cells to reverse abnormal changes and restore homeostasis of the pulmonary environment, thereby showing good therapeutic activity and reduced toxicity. This article reviews the latest applications of nanomedicine in pre-clinical ARDS therapy, highlights the strategies for targeted treatment of lung inflammation, presents the innovative drug delivery systems, and provides inspiration for strengthening the therapeutic effect of nanomedicine-based treatment.
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  • 文章类型: Journal Article
    Irisin,从骨骼肌中释放出来的肌动因子,最近发现作为间充质细胞上表达的整合素αVβ5,αVβ1和α5β1的配体,从而在骨骼的代谢重塑中发挥重要作用,骨骼肌和脂肪组织。尽管已经证明了irisin在慢性炎症中的免疫调节作用,其与淋巴细胞整合素的相互作用尚未阐明。这里,我们显示irisin支持人和小鼠淋巴细胞的细胞粘附。使用一组针对整联蛋白的抑制性抗体的细胞粘附测定表明,irisin介导的淋巴细胞粘附涉及多种整联蛋白,不仅包括α4β1和α5β1,还包括白细胞特异性αLβ2和α4β7。重要的是,缺乏β1整合素表达的小鼠淋巴细胞TK-1细胞表现出αLβ2-和α4β7介导的细胞对irisin的粘附。Irisin也已被证明与纯化的重组整联蛋白αLβ2和α4β7蛋白结合。因此,irisin代表整联蛋白αLβ2和α4β7的新型配体,能够独立于β1整联蛋白支持淋巴细胞粘附。这些结果表明,irisin可能在调节发炎的脉管系统中的淋巴细胞粘附和迁移中起重要作用。
    Irisin, a myokine released from skeletal muscle, has recently been found to act as a ligand for the integrins αVβ5, αVβ1, and α5β1 expressed on mesenchymal cells, thereby playing an important role in the metabolic remodeling of the bone, skeletal muscle and adipose tissues. Although the immune-modulatory effects of irisin in chronic inflammation have been documented, its interactions with lymphocytic integrins have yet to be elucidated. Here, we show that irisin supports the cell adhesion of human and mouse lymphocytes. Cell adhesion assays using a panel of inhibitory antibodies to integrins have shown that irisin-mediated lymphocyte adhesion involves multiple integrins including not only α4β1 and α5β1, but also leukocyte-specific αLβ2 and α4β7. Importantly, mouse lymphocytic TK-1 cells that lack the expression of β1 integrins have exhibited αLβ2- and α4β7-mediated cell adhesion to irisin. Irisin has also been demonstrated to bind to purified recombinant integrin αLβ2 and α4β7 proteins. Thus, irisin represents a novel ligand for integrin αLβ2 and α4β7, capable of supporting lymphocyte cell adhesion independently of β1 integrins. These results suggest that irisin may play an important role in regulating lymphocyte adhesion and migration in the inflamed vasculature.
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  • 文章类型: Journal Article
    肾缺血再灌注与炎症和氧化应激有关。作为黑胡椒中的主要化合物,胡椒碱具有抗炎和抗氧化特性。在目前的研究中,研究了口服胡椒碱对肾缺血再灌注(IR)诱导的急性肾损伤(AKI)的保护作用。
    雄性Wistar大鼠接受胡椒碱(10或20mg/kg。bw)或车辆10天。然后夹住两个肾脏的动脉和静脉30分钟,然后是24小时再灌注期。测量降主动脉血液中肌酐和尿素氮的浓度,并测定肾脏组织中丙二醛(MDA)和铁还原/抗氧化能力(FRAP)水平以评估氧化应激。通过使用RealTimePCR方法测量肾皮质组织中TNF-α和ICAM-1mRNA的表达水平并计数白细胞向间质的浸润来评估炎症。进一步测量H&E染色切片中的组织损伤。
    肾IR降低FRAP,同时增加肌酐和尿素氮的血浆浓度,组织MDA水平,TNF-α和ICAM-1mRNA表达,白细胞浸润和组织病理学损伤。胡椒碱给药显著降低肌酐和尿素氮的血浆浓度,促炎因子的表达,氧化应激和肾组织病理学损伤。应当注意,20mg/kg剂量更有效。
    我们的结果表明,胡椒碱通过其抗炎和抗氧化特性保护肾脏免受缺血再灌注引起的急性肾损伤。
    UNASSIGNED: Renal ischemia-reperfusion is associated with inflammation and oxidative stress. As a major compound in black pepper, piperine has anti-inflammatory and anti-oxidative properties. In present study, the protective effects of oral administration of piperine in renal ischemia-reperfusion (IR) induced acute kidney injuries (AKI) were investigated.
    UNASSIGNED: Male Wistar rats received piperine (10 or 20 mg/kg.bw) or vehicle for 10 days. The artery and vein of both kidneys were then clamped for 30 min, followed by a 24-h reperfusion period. Concentrations of creatinine and urea-nitrogen in descending aorta blood were measured, and malondialdehyde (MDA) and ferric reducing/antioxidant power (FRAP) levels were measured in kidney tissue to evaluate the oxidative stress. Inflammation was evaluated by measuring the TNF-α and ICAM-1 mRNA expression levels in renal cortical tissue using Real Time PCR method and counting leukocytes infiltration to interstitium. Further measured were tissue damages in H & E stained sections.
    UNASSIGNED: Renal IR reduced FRAP, while increasing the plasma concentrations of creatinine and urea-nitrogen, tissue MDA level, TNF-α and ICAM-1 mRNA expressions, leukocyte infiltration and histopathologic injuries. Piperine administration significantly reduced the plasma concentrations of creatinine and urea-nitrogen, expression of pro-inflammatory factors, oxidative stress and renal histopathologic injuries. It is to be noted that 20 mg/kg dose was more effective.
    UNASSIGNED: Our results suggest piperine protects the kidney against ischemia-reperfusion induced acute kidney injuries by its anti-inflammatory and anti-oxidative properties.
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  • 文章类型: Journal Article
    在动脉粥样硬化病变中,血管壁的广泛炎症导致斑块不稳定。长链非编码RNA(lncRNAs)在动脉粥样硬化的多种生物学过程中发挥重要作用。
    这里,我们旨在确定lncRNA缺氧诱导因子1α-反义RNA2(HIF1A-AS2)在动脉粥样硬化性炎症中的功能作用和调节机制.
    通过高脂饮食(HFD)在ApoE-/-小鼠中诱导动脉粥样硬化小鼠模型。内皮细胞(ECs),将人主动脉平滑肌细胞(SMC)或人冠状动脉内皮细胞(HCAEC)暴露于ox-LDL以建立体外模型。lncRNAHIF1A-AS2对炎症的影响通过测定炎症因子肿瘤坏死因子-α(TNF-α)的水平来评估,白细胞介素-1β(IL-1β)和白细胞介素-6(IL-6)和粘附分子血管细胞粘附分子1(VCAM-1)的水平,细胞间粘附分子1(ICAM-1),和巨噬细胞阳离子肽1(MCP-1)。
    已确定lncRNAHIF1A-AS2和ATF2在动脉粥样硬化ApoE-/-小鼠中高表达。在ox-LDL暴露的ECs中下调lncRNAHIF1A-AS2,SMC和HCAECs通过降低促炎因子和粘附分子的水平来抑制炎症。LncRNAHIF1A-AS2与转录因子USF1结合以提高ATF2表达。USF1过表达抵消了lncRNAHIF1A-AS2沉默对ox-LDL诱导的炎症的抑制作用。敲除lncRNAHIF1A-AS2或ATF2也可以减轻动脉粥样硬化小鼠的炎症。总的来说,本研究表明,lncRNAHIF1A-AS2的下调抑制了USF1与ATF2启动子区的结合,然后抑制ATF2的表达,从而抑制动脉粥样硬化炎症。
    该研究表明lncRNAHIF1A-AS2是动脉粥样硬化的有希望的治疗靶标。
    UNASSIGNED: In atherosclerotic lesions, extensive inflammation of the vessel wall contributes to plaque instability. Long noncoding RNAs (lncRNAs) play important roles in diverse biological processes in atherosclerosis.
    UNASSIGNED: Here, we aim to identify the functional role and regulatory mechanisms of lncRNA hypoxia-inducible factor 1 alpha-antisense RNA 2 (HIF1A-AS2) in atherosclerotic inflammation.
    UNASSIGNED: An atherosclerotic mouse model was induced in ApoE-/- mice by high fat diet (HFD). Endothelial cells (ECs), human aortic smooth muscle cells (SMCs) or human coronary artery endothelial cells (HCAECs) were exposed to ox-LDL to develop the in vitro model. The effects of lncRNA HIF1A-AS2 on inflammation were evaluated by determining levels of inflammatory factors tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) and levels of adhesion molecules vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), and macrophage cationic peptide 1 (MCP-1).
    UNASSIGNED: It was established that lncRNA HIF1A-AS2 and ATF2 were highly expressed in atherosclerotic ApoE-/- mice. Downregulating lncRNA HIF1A-AS2 in ox-LDL-exposed ECs, SMCs and HCAECs inhibited inflammation by reducing levels of pro-inflammatory factors and adhesion molecules. LncRNA HIF1A-AS2 bound to the transcription factor USF1 to elevate ATF2 expression. USF1 overexpression counteracted the suppressive effect of lncRNA HIF1A-AS2 silencing on ox-LDL-induced inflammation. Knockdown of lncRNA HIF1A-AS2 or ATF2 could also attenuate inflammation in atherosclerotic mice. Collectively, the present study demonstrates that downregulation of lncRNA HIF1A-AS2 represses the binding of USF1 to the ATF2 promoter region and then inhibits ATF2 expression, thereby suppressing atherosclerotic inflammation.
    UNASSIGNED: This study suggests lncRNA HIF1A-AS2 as an promising therapeutic target for atherosclerosis.
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  • 文章类型: Journal Article
    虫媒病毒如西尼罗河病毒(WNV),蓝舌病毒(BTV),登革热病毒(DENV)和基孔肯雅病毒(CHIKV)在取决于环境温度的平均温度范围内感染其节肢动物载体。虫媒病毒的传播效率(即媒介能力)如何随温度变化,不仅会影响人类和牲畜中虫媒病毒暴发的短期风险,还会影响气候变化对病毒地理范围的长期影响。病毒表面(glyco)蛋白(GP)与宿主细胞受体(Cr)之间在病毒与宿主细胞结合时的相互作用强度由热力学解离常数Kd_受体定义,该常数假定等于10-3M(在37°C下)节肢动物中肠上皮细胞表面的唾液酸(SA)与BTV表面的SA结合位点结合,例如。在此,病毒结合亲和力是通过在10°C至35°C的温度下增加GP/Cr接触的数量来建模的,同时考虑了整个病毒在结合时固定的熵的变化(ΔSa_immob)。根据公布的数据,三种热力学GP/Cr结合方案,即焓驱动,熵辅助和熵驱动,显示以不同方式影响病毒结合的温度敏感性。因此,对于焓驱动的GP/Cr结合,病毒在10°C比35°C时更强烈地结合宿主细胞。建立了具有结合病毒的节肢动物中肠细胞数量的机制模型,并建立了虫媒病毒复制速率并随后传播到节肢动物唾液腺的动力学成分,建立了温度对矢量能力影响的模型。该模型将温度对中肠细胞结合亲和力的相反影响与病毒发生的动力学成分分开。它成功地适应了蚊子中DENV和WNV的媒介能力随温度的升高,以及各种白纹伊蚊种群中CHIKV2010-1909株的降低。通过焓驱动的GP/Cr结合在较低温度下增强的细胞结合在一定程度上补偿了较低的复制速率,使得在较低温度下仍然可以发生一些传播。相比之下,熵驱动的GP/Cr结合的强度在低温下减弱,尽管传输效率没有最低温度阈值。ΔSa_immob的大小是重要的数据间隙。结论是,在分子水平上获得的热力学和动力学数据对于模拟温度的矢量能力至关重要。
    Arboviruses such as West Nile virus (WNV), bluetongue virus (BTV), dengue virus (DENV) and chikungunya virus (CHIKV) infect their arthropod vectors over a range of average temperatures depending on the ambient temperature. How the transmission efficiency of an arbovirus (i.e. vector competence) varies with temperature influences not only the short term risk of arbovirus outbreaks in humans and livestock but also the long term impact of climate change on the geographical range of the virus. The strength of the interaction between viral surface (glyco)protein (GP) and the host cell receptor (Cr) on binding of virus to host cell is defined by the thermodynamic dissociation constant Kd_receptor which is assumed to equal 10-3 M (at 37 °C) for binding of a sialic acid (SA) on the arthropod midgut epithelial cell surface to a SA-binding site on the surface of BTV, for example. Here virus binding affinity is modelled with increasing number of GP/Cr contacts at temperatures from 10 °C to 35 °C taking into account the change in entropy on immobilization of the whole virus on binding (ΔSa_immob). Based on published data, three thermodynamic GP/Cr binding scenarios, namely enthalpy-driven, entropy-assisted and entropy-driven, are shown to affect the temperature sensitivity of virus binding in different ways. Thus for enthalpy-driven GP/Cr binding, viruses bind host cells much more strongly at 10 °C than 35 °C. A mechanistic model is developed for the number of arthropod midgut cells with bound virus and by building in a kinetic component for the rate of arbovirus replication and subsequent spread to the arthropod salivary glands, a model for the effect of temperature on vector competence is developed. The model separates the opposing effects of temperature on midgut cell binding affinity from the kinetic component of virogenesis. It successfully accommodates both increases in vector competence with temperature as for DENV and WNV in mosquitoes and decreases as for the CHIKV 2010-1909 strain in various populations of Aedes albopictus mosquitoes. Enhanced cell binding at lower temperatures through enthalpy-driven GP/Cr binding compensates for the lower replication rate to some degree such that some transmission can still occur at lower temperatures. In contrast, the strength of entropy-driven GP/Cr binding diminishes at low temperatures although there is no minimum temperature threshold for transmission efficiency. The magnitude of ΔSa_immob is an important data gap. It is concluded that thermodynamic and kinetic data obtained at the molecular level will prove important in modelling vector competence with temperature.
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