A matrix metalloproteinase-responsive hydrogel system controls angiogenic peptide release for repair of cerebral ischemia/reperfusion injury

Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion injury.Current studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion injury.However,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional exploration.In this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and autophagy.The therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box O.This review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins expression.This review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk factors.While Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug therapies.Overall,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

Network-pharmacology-based research on protective effects and underlying mechanism of Shuxin decoction against myocardial ischemia/reperfusion injury with diabetes

BACKGROUND Patients with diabetes mellitus are at higher risk of myocardial ischemia/reperfusion injury(MI/RI).Shuxin decoction(SXT)is a proven recipe modification from the classic herbal formula"Wu-tou-chi-shi-zhi-wan"according to the traditional Chinese medicine theory.It has been successfully used to alleviate secondary MI/RI in patients with diabetes mellitus in the clinical setting.However,the underlying mechanism is still unclear.AIM To further determine the mechanism of SXT in attenuating MI/RI associated with diabetes.METHODS This paper presents an ensemble model combining network pharmacology and biology.The Traditional Chinese Medicine System Pharmacology Database was accessed to select key components and potential targets of the SXT.In parallel,therapeutic targets associated with MI/RI in patients with diabetes were screened from various databases including Gene Expression Omnibus,DisGeNet,Genecards,Drugbank,OMIM,and PharmGKB.The potential targets of SXT and the therapeutic targets related to MI/RI in patients with diabetes were intersected and subjected to bioinformatics analysis using the Database for Annotation,Visualization and Integrated Discovery.The major results of bioinformatics analysis were subsequently validated by animal experiments.RESULTS According to the hypothesis derived from bioinformatics analysis,SXT could possibly ameliorate lipid metabolism disorders and exert anti-apoptotic effects in MI/RI associated with diabetes by reducing oxidized low density lipoprotein(LDL)and inhibiting the advanced glycation end products(AGE)-receptor for AGE(RAGE)signaling pathway.Subsequent animal experiments confirmed the hypothesis.The treatment with a dose of SXT(2.8 g/kg/d)resulted in a reduction in oxidized LDL,AGEs,and RAGE,and regulated the level of blood lipids.Besides,the expression of apoptosis-related proteins such as Bax and cleaved caspase 3 was down-regulated,whereas Bcl-2 expression was up-regulated.The findings indicated that SXT could inhibit myocardial apoptosis and improve cardiac function in MI/RI in diabetic rats.CONCLUSION This study indicated the active components and underlying molecular therapeutic mechanisms of SXT in MI/RI with diabetes.Moreover,animal experiments verified that SXT could regulate the level of blood lipids,alleviate cardiomyocyte apoptosis,and improve cardiac function through the AGE-RAGE signaling pathway.

Post reperfusion syndrome during liver transplantation:From pathophysiology to therapy and preventive strategies

This review aims at evaluating the existing evidence regarding post reperfusion syndrome, providing a description of the pathophysiologic mechanisms involved and possible management and preventive strategies. A Pub Med search was conducted using the Me SH database, "Reperfusion" AND "liver transplantation" were the combined Me SH headings; EMBASE and the Cochrane library were also searched using the same terms. 52 relevant studies and one ongoing trial were found. The concept of post reperfusion syndrome has evolved through years to a multisystemic disorder. The implications of the main organ, recipient and procedure related factors in the genesis of this complex syndrome are discussed in the text as the novel pharmacologic and technical approaches to reduce its incidence. However the available evidence about risk factors, physiopathology and preventive measures is still confusing, the presence of two main definitions and the numerosity of possible confounding factors greatly complicates the interpretation of the studies.

Role of nitric oxide in hepatic ischemia-reperfusion injury

Hepatic ischemia-reperfusion injury (IRI) occurs upon restoration of hepatic blood flow after a period of ischemia. Decreased endogenous nitric oxide (NO) production resulting in capillary luminal narrowing is central in the pathogenesis of IRI. Exogenous NO has emerged as a potential therapy for IRI based on its role in decreasing oxidative stress,cytokine release,leukocyte endothelial-adhesion and hepatic apoptosis. This review will highlight the influence of endogenous NO on hepatic IRI,role of inhaled NO in ameliorating IRI,modes of delivery,donor drugs and potential side effects of exogenous NO.

Japanese herbal medicine, Saiko-keishi-to, prevents gut ischemia/reperfusion-induced liver injury in rats via nitric oxide

AIM:To determine whether Saiko-keishi-to(TJ-10),a Japanese herbal medicine,could protect liver injury induced by gut ischemia/reperfusion(I/R),and to investigate the role of NO. METHODS:Male Wistar rats were exposed to 30-min gut isohemia followed by 60 min of reperfusion.Intravital microscopy was used to monitor leukocyte recruitment.Plasma tumor necrosis factor(TNF)levels and alanine aminotransferase (ALT)activities were measured.TJ-10 1 g/(kg.d)was intragastrically administered to rats for 7 d.A NO synthase inhibitor was administered. RESULTS:In control rats,gut I/R elicited increases in the number of stationary leukocytes,and plasma TNF levels and ALT activities were mitigated by pretreatment with TJ-10.Pretreatment with the NO synthase inhibitor diminished the protective effects of TJ-10 on leukostasis in the liver,and the increase of plasma TNF levels and ALT activities.Pretreatment with TJ-10 increased plasma nitrite/nitrate levels. CONCLUSION:TJ-10 attenuates the gut I/R-induced hepatic microvascular dysfunction and sequential hepatocellular injury via enhancement of NO production.

Heat shock protein 72 normothermic ischemia,and the impact of congested portal blood reperfusion on rat liver

INTRODUCTIONFrom the technical aspect of liver surgery ,control of bleeding during hepatic parenchymal resection is one of the most important procedures in hepatectomy .Pringle,s maneuver ,a temporary cross-clamping of the hepatoduodnal ligament ,has often been used for this purpose[1],This is the simplest and userul technique to reduce intraoperative blood loss .

Protective effects of bifunctional platelet GPIIIa49-66 ligand on myocardial ischemia-reperfusion injury in rats

Current antiplatelet drugs mainly focus on prevention rather than the more clinically relevant issue of clearance of an existing thrombus. We recently described a novel and effective therapeutic strategy for dissolution of preexisting platelet thrombus in a murine ischemic stroke model with a bifunctional platelet GPIIIa49-66 ligand (Single-chain antibody Linked first Kringle 1 of plasminogen, named SLK), which homes to newly deposited fibrin strands tangled of platelet thrombus and induces aggregated platelet fragmentation. In this study, we perform in-depth analysis of the effect of SLK on myocardial ischemia-reperfusion (IR) injury in rats. We show that SLK dose-dependently reduces lactate dehydrogenase (LDH) release as well as mean infarction size of left ventricle. Histological observation demonstrates that the arterial thrombi in coronary arteries of rat almost disappear after SLK injection. Optimal dose of SLK (37.5 μg/ individual) provides the myocardial protection at 2 hours post-infusion. However, there are no significant protective effects if SLK was given at 4 or 8 hours post-infusion. The combined application of SLK and urokinase (UK) demonstrates greater myocardial protection than UK alone at 2 hours post-infusion. Thus, SLK could be used as a thrombolytic alternative in other arterial vascular beds associated with thrombosis to enhance fibrinolysis.

Prevention of grafted liver from reperfusive injury

INTRODUCTIONThe incidence of primary non-function(PNF)of grafted liver in the early postoperative stage is 2%-23%[1-4],its main cause is the ischemic-rechemic injure[5,6].In this experiment,anisodamine was added into the preserving fluid and the grafted liver was rewarmed at different temperatures to protect the cell membranc and prevent ischemic-reperfusive injury.

细胞焦亡在肾缺血再灌注损伤中的研究进展

缺血再灌注损伤(ischemia-reperfusion injury,IRI)是导致急性肾损伤的主要原因之一,目前尚无有效的治疗方法。探索肾IRI的发生机制及开发减轻肾IRI的有效靶向药物具有重要意义。细胞焦亡是一种新发现的炎症性程序性细胞死亡方式。研究发现细胞焦亡与肾IRI的发生发展密切相关。该文对细胞焦亡在肾IRI中的作用及机制进行综述,并讨论影响细胞焦亡的相关药物在肾IRI保护作用中的研究新进展,为肾IRI的治疗提供新思路。

细胞焦亡在心肌缺血再灌注损伤中的作用

细胞焦亡是一种新型促炎性细胞程序性死亡方式,其由NOD样受体热蛋白结构域相关蛋白3炎症小体活化启动,gasdermin D蛋白活性N端破坏细胞膜完整性,导致细胞死亡,随后引发炎症级联反应加重组织损伤。有研究表明,细胞焦亡可能参与心肌缺血再灌注损伤(MIRI)的发生发展。MIRI是限制急性心肌梗死临床疗效的重要原因之一。针对细胞焦亡的药物在MIRI疾病模型中能够挽救细胞焦亡所致心肌损伤。现就细胞焦亡在MIRI中的作用做一综述,并在此基础上探讨可能的治疗靶点。

药物治疗在肝切除术中预防缺血再灌注损伤的研究进展

肝切除术中常采用肝门阻断和控制中心静脉压的方法减少出血,保证手术视野清晰,从而使手术顺利进行,但在肝门阻断和开放过程中会导致肝脏缺血再灌注损伤(hepatic ischemia-reperfusion injury,HIRI)、胃肠道淤血、肠源性细菌移位等问题。因此,围术期采取各种措施减轻因肝门阻断引起的HIRI进而提高手术的安全性成为肝切除术的研究热点。缺血预处理、亚低温处理、药物治疗、抗凋亡基因治疗等方法应运而生,其中药物治疗具有可操作性强、相对安全、临床上易操作等优势,因而受到广泛关注。本文对有助于改善HIRI的部分代表药物及作用机制进行总结,为HIRI的临床诊治提供参考。

核转录因子红系2相关因子2在肝缺血再灌注损伤中的作用及麻醉药物干预的研究进展

肝缺血再灌注损伤(IRI)是一种常见的肝脏损伤类型,严重影响患者预后。核转录因子红系2相关因子2(Nrf2)是一种重要的转录因子,参与多种细胞生理活动。研究表明,Nrf2在肝脏IRI中起重要调控作用,激活Nrf2及相关通路能够清除活性氧,减少氧化应激损伤,从而减轻肝脏IRI。近年来,麻醉药物调控Nrf2信号通路在基础实验和临床试验中减轻肝脏IRI均取得一定成果,但仍处于实验阶段。本文通过分析近年来麻醉药物相关研究进展,对Nrf2在肝脏IRI中的作用及机制进行综述,以期为肝脏IRI的防治提供新方向。

失血性休克后肾脏保护的研究进展

失血性抗休克是一种由于创伤等原因引起的临床常见的急危重症。尤其是肾脏在缺血缺氧后引起的局部组织灌注不足和细胞缺氧,极易导致急性肾损伤。临床上在不断探寻患者失血性休克后更安全、实用和有效的复苏方法,如从晶胶液体到高渗液体、从常压复苏到低压复苏、从纠正血压到恢复组织细胞的氧供、从维持血流动力学稳定到抑制细胞凋亡、从血管活性药到中药再到酶抑制剂的应用等等,以达到更好地保护肾脏的目的。本文就近年来关于失血性休克患者肾脏的保护研究进展进行综述。

基于网络药理学及计算机辅助药物设计方法分析雷诺嗪治疗心肌缺血再灌注损伤致心律失常的潜在靶点及机制

目的利用网络药理学方法和计算机辅助药物设计策略,分析雷诺嗪对心肌缺血再灌注损伤(MIRI)致心律失常的潜在治疗靶点及机制。方法采用Swiss Target Prediction数据库和DrugBank数据库预测雷诺嗪潜在的作用靶点。采用GeneCards数据库搜集MIRI和心律失常疾病的靶点,检索时间为建库至2023年1月26日,将雷诺嗪、MIRI和心律失常相关靶点进行交集比对以获取雷诺嗪治疗MIRI致心律失常的关键靶点。利用STRING数据库和Cytoscape软件绘制靶点蛋白互相作用网络。利用DAVID数据库对靶点进行信号通路富集分析。利用Cy-toscape软件构建药物-靶点-信号通路网络。利用分子对接软件验证雷诺嗪与交集靶点结合能力。最后通过分子相似性分析及分子动力学模拟研究,验证预测靶点的准确性。结果筛选获得雷诺嗪治疗MIRI致心律失常的潜在作用靶点30个。通过蛋白互相作用分析共获得8个核心靶点,包括SRC、PIK3CA、MAPK8、MAPK14、JAK1、MAP2K1、JAK2和PIK3CG。GO生物分析共筛选出177个生物学过程,其中包括123个细胞生物过程,23个细胞组成和31个分子功能。KEGG分析发现119条相关信号通路。分子对接分析结果显示,雷诺嗪与8个核心靶蛋白均具有较好的亲和力。分子相似性分析结果显示,雷诺嗪与8个核心靶蛋白原配体都存在一定相似性。分子动力学模拟了相关性最高的3个靶点(SCR、PIK3CA和MAPK8),结果显示雷诺嗪表现出MAPK8和SCR抑制剂潜力,而对PIK3CA的抑制剂位点结合潜力相对较差,结合文献复习,推测出雷诺嗪对MIRI致心律失常治疗作用的最相关分子机制。结论雷诺嗪可通过多靶点、多途径治疗MIRI致心律失常,这对促进治疗MIRI致心律失常靶向药物的研发及临床应用具有重要意义。

活血荣络方含药血清对氧糖剥夺/复氧糖损伤PC12细胞线粒体自噬的影响及机制研究

目的基于氧糖剥夺/复氧糖(OGD/R)损伤的PC12细胞模型观察活血荣络方含药血清对线粒体自噬的影响及作用机制。方法采用OGD/R损伤PC12细胞模拟体外脑缺血再灌注损伤模型,将细胞分为正常对照组、模型组、空白血清组、活血荣络方含药血清组和雷帕霉素组,采用相应血清进行干预,JC-1荧光探针检测线粒体膜电位(MMP),免疫荧光染色检测线粒体-LC3B共定位、线粒体-PINK1-Parkin共定位,Western blot检测微管蛋白1轻链3B(LC3B)、p62、线粒体外膜转位酶20(TOMM20)、PTEN诱导假定激酶1(PINK1)、Parkin蛋白表达。结果与正常对照组比较,模型组细胞MMP明显降低(P<0.01),线粒体-LC3B共定位无明显变化,线粒体-PINK1-Parkin共定位增强,LC3B、PINK1、Parkin蛋白表达明显升高,p62、TOMM20蛋白表达明显降低,差异均有统计学意义(P<0.05,P<0.01);与模型组比较,活血荣络方含药血清组细胞MMP明显升高(P<0.01),线粒体-LC3B共定位和线粒体-PINK1-Parkin共定位增强,LC3B、PINK1、Parkin蛋白表达明显升高(P<0.05,P<0.01),p62、TOMM20蛋白表达明显降低(P<0.05,P<0.01)。结论活血荣络方含药血清可减轻OGD/R诱导的PC12细胞损伤,其机制可能与调控PINK1/Parkin通路,增加Parkin蛋白的线粒体转位,上调LC3B,下调p62、TOMM20蛋白表达,激活线粒体自噬相关。

远隔缺血预适应对药物球囊扩张术后冠状动脉功能学的影响

目的:本研究旨在探索接受药物球囊(drug-coated balloon,DCB)扩张术的非ST段抬高型急性冠状动脉综合征(non-ST-segment elevation-acute coronary syndrome,NSTEACS)人群中,远隔缺血预适应(distal ischemic preconditioning,RIPC)对冠状动脉功能学的影响。方法:研究纳入2019年10月至2020年10月,就诊于郑州大学第一附属医院明确诊断为NSET-ACS并使用DCB治疗冠状动脉原位病变的患者120例。根据术前是否进行RIPC处理分为两组:对照组(n=60)和RIPC组(n=60)。主要结局:术前术后冠状动脉血流储备分数(fraction coronary flow reserve,FFR)的变化值。次要结局:术前FFR值和术后FFR值。通过多元线性回归分析关键变量与FFR变化值的关系。结果:两组的FFR变化值[(0.26±0.03)vs.(0.19±0.03),P<0.001]和术后[(0.91±0.04)vs.(0.85±0.03),P<0.001]。两组术前FFR值差异无统计学意义。在多元线性回归分析中,ACEI(β=0.11,95%CI:0.01~0.22,P=0.048)、RIPC(β=0.82,95%CI:0.71~0.93,P<0.001)与FFR变化值呈正相关。吸烟(β=-0.13,95%CI:-0.23~-0.01,P=0.027)、高血压(β=-0.14,95%CI:-0.25~-0.02,P=0.019)、回旋支病变(β=-0.12,95%CI:-0.23~-0.01,P=0.031)与FFR变化值呈负相关。结论:在接受DCB扩张术的CNSTE-ACS患者人群中,RIPC组术前术后FFR变化值及术后FFR值明显高于对照组。

川芎嗪-灯盏乙素苷元孪药对脑缺血再灌注损伤模型大鼠的保护作用及机制研究

目的 研究川芎嗪-灯盏乙素苷元孪药(TMSC4)对脑缺血再灌注损伤(CIRI)模型大鼠的保护作用及机制。方法 将105只SD大鼠随机分为假手术组、模型组、灯盏乙素苷元组(0.7 mmol/kg)、川芎嗪组(0.7 mmol/kg)和TMSC4低、中、高剂量组(0.35、0.7、1.4 mmol/kg),每组15只。假手术组、模型组大鼠灌胃等体积生理盐水,其余各组大鼠灌胃相应药物,每天1次,连续14 d。除假手术组外,其余各组大鼠均采用线栓法建立CIRI模型。大鼠缺血2 h再灌注22 h后,测定大鼠脑指数及脑含水量;检测大鼠血清中白细胞介素1β(IL-1β)、IL-6、肿瘤坏死因子α(TNF-α)的水平,脑组织中超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽过氧化氢酶(GSH-Px)、过氧化氢酶(CAT)的水平和大脑皮层神经细胞的凋亡情况以及B细胞淋巴瘤2(Bcl-2)、Bcl-2相关X蛋白(Bax)、活化型胱天蛋白酶3(cleaved-caspase-3)蛋白表达水平。结果 与假手术组比较,模型组大鼠脑指数和脑含水量,血清中IL-1β、IL-6、TNF-α水平以及脑组织中MDA水平,神经细胞凋亡率,Bax、cleaved-caspase-3蛋白表达水平均显著升高(P<0.05);脑组织中SOD、 GSH-Px、CAT水平和Bcl-2蛋白表达水平均显著降低(P<0.05)。与模型组比较,各给药组大鼠上述指标水平均显著逆转(P<0.05),且TMSC4中、高剂量组的逆转作用显著优于灯盏乙素苷元组和川芎嗪组(P<0.05)。结论 TMSC4对CIRI模型大鼠具有保护作用,其作用机制可能与减轻炎症反应、氧化应激损伤,抑制神经细胞凋亡有关。

Pretreatment with Tongxinluo protects porcine myocardium from ischaemia/reperfusion injury through a nitric oxide related mechanism

Background The traditional Chinese medicine injury, but the mechanism of its action is not we protective role of Tongxinluo. Tongxinluo can protect myocardium against documented. We examined the involvement schaemia/reperfusion of nitric oxide in the Methods Miniswine were randomized to four groups of seven： sham, control, Tongxinluo and Tongxinluo coadministration with a nitric oxide synthase inhibitor N^ωnitro-L-arginine （L-NNA, 10 mg/kg i.v.）. Three hours after administration of Tongxinluo, the animals were anaesthetised and the left anterior descending coronary artery ligated and maintained in situ for 90 minutes followed by 3 hours of reperfusion before death. Area of no reflow and necrosis and risk region were determined pathologically by planimetry. The degree of neutrophil accumulation in myocardium was obtained by measuring myeloperoxidase activity and histological analysis. Myocardial endothelial nitric oxide synthase activity and vascular endothelial cadherin content were measured by colorimetric method and immunoblotting analysis respectively. Results Tongxinluo significantly increased the local blood flow and limited the infarct and size of no reflow. Tongxinluo also attenuated myeloperoxidase activity and neutrophil accumulation in histological sections and maintained the level of vascular endothelial cadherin and endothelial nitric oxide synthase activity in the reflow region when compared with control group. The protection of Tongxinluo was counteracted by coadministration with L-NNA. Conclusions Tongxinluo may limit myocardial ischaemia and protect the heart against reperfusion injury. Tongxinluo regulates synthesis of nitric oxide by altering activity of endothelial nitric oxide synthase.

基于外泌体的多细胞信号网络和药物载体在调控脑缺血再灌注损伤中的研究进展

脑卒中是全球第二大死因,在多种疾病中卒中的致死率与致残率总和占据第三位,其中主要以缺血性脑卒中为主,占全部卒中事件的62.4%,而在我国脑卒中是第一大致死性疾病和致残性疾病,同时患病率和死亡率在继续增加^([1-2])。近年来,我国各级医院的卒中管理机制在不断完善,溶栓、颅内动脉取栓术、颈动脉支架植入术等再灌注策略更多地应用于脑卒中患者,大幅度地改善了患者的住院期间生存率、降低了年龄标准化死亡率,然而接受再灌注治疗患者的远期预后和生存质量仍较差,造成上述结果的原因除了社会老龄化导致的患者平均年龄升高外,由再灌注策略引发的脑缺血再灌注损伤(cere‐bral ischemia-reperfusion injury,CIRI)也发挥着重要作用^([3-4])。