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.

Advances in extracellular vesicle-based combination therapies for spinal cord injury

Spinal cord injury is a severe insult to the central nervous system that causes persisting neurological deficits.The currently available treatments involve surgical,medical,and rehabilitative strategies.However,none of these techniques can markedly reverse neurological deficits.Recently,extracellular vesicles from various cell sources have been applied to different models of spinal cord injury,thereby generating new cell-free therapies for the treatment of spinal cord injury.However,the use of extracellular vesicles alone is still associated with some notable shortcomings,such as their uncertainty in targeting damaged spinal cord tissues and inability to provide structural support to damaged axons.Therefore,this paper reviews the latest combined strategies for the use of extracellular vesicle-based technology for spinal cord injury,including the combination of extracellular vesicles with nanoparticles,exogenous drugs and/or biological scaffold materials,which facilitate the targeting ability of extracellular vesicles and the combinatorial effects with extracellular vesicles.We also highlight issues relating to the clinical transformation of these extracellular vesicle-based combination strategies for the treatment of spinal cord 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.

Induction of Autologous Bone-Marrow Stem Cells by Low-Level Laser Therapy Has Beneficial Effects on the Kidneys Post-Ischemia-Reperfusion Injury in the Rat

Acute renal failure has a 50% - 80% mortality rate. Currently, treatment options for this life-threatening disease are limited. Low-level laser therapy (LLLT) has been found to modulate biological activity. The aim of the present study was to investigate the possible beneficial effects of laser application to stem cells in the bone marrow, on the kidneys of rats that had undergone ischemia-reperfusion injury (IRI). IRI was induced by occlusion of the renal artery to 3- and 7-month-old rats for 15 or 30 minutes. In an additional experiment IRI was applied to both kidneys for 20 min each in 2-3-month-old rats. Rats were then divided randomly into two groups of control and laser-treated. Laser therapy (Ga-Al-As 810 nm, 200 mW output for 2 min) was applied to the bone marrow 1 and 7 days post-IRI to the kidneys, and rats were sacrificed 2 weeks later. Histomorphometry and immunohistochemistry were performed on kidney sections and blood markers for kidney function. Quantitative histomorphometric analysis revealed a reduction in dilatation of the renal tubules, restored structural integrity of the renal tubules, and reduced necrosis in the laser-treated rats as compared to the control, non-laser-irradiated group. C-kit positive cell density in kidneys post-IRI and laser-treatment was significantly (p = 0.015) 3.2-fold higher compared to the control group. Creatinine and blood urea nitrogen content were significantly lower in the laser-treated rats as compared to control. It is concluded that LLLT application to the bone marrow (BM) causes a significant increase in the density of mesenchymal stem cells in the kidneys post-IRI, probably by induction of stem cells in the BM, which subsequently migrate to the IRI kidney, significantly reducing the pathological features of the kidney and increasing kidney function post IRI.

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.

Comparison of the anti-apoptotic effects of 15-and 35-minute suspended moxibustion after focal cerebral ischemia/reperfusion injury

Heat-sensitive suspended moxibustion has a neuroprotective effect against focal cerebral ischemia/reperfusion injury, but the underly- ing mechanisms remain unclear. The duration of heat-sensitive suspended moxibustion （usually from 30 minutes to 1 hour） is longer than traditional suspended moxibustion （usually 15 minutes）. However, the effects of 15- and 35-minute suspended moxibustion in rats with cerebra/ischemia/reperfusion injury are poorly understood. In this study, we performed 15- or 35-minute suspended moxibustion at acupoint Dazhui （GV14） in an adult rat model of focal cerebral ischemia/reperfusion injury. Infarct volume was evaluated with the 2,3,5-triphenyltetrazolium chloride assay. Histopathological changes and neuronal apoptosis at the injury site were assessed by hematoxy- lin-eosin staining and terminal deoxynucleotidyl transferase dUTP nick end labeling assay. Caspase-9 and caspase-3 expression at the in- jury site was detected using immunofluorescent staining. Bax and Bcl-2 expression at the injury site was assessed using western blot assay. In the 35-minute moxibustion group, infarct volume was decreased, neuronal apoptosis was reduced, caspase-9, caspase-3 and Bax expres- sion was lower, and Bcl-2 expression was increased, compared with the 15-minute moxibustion group. Our findings show that 35-minute moxibustion has a greater anti-apoptotic effect than 15-minute moxibustion after focal cerebral ischemia/reperfusion injury.

Interferon-γpriming enhances the therapeutic effects of menstrual blood-derived stromal cells in a mouse liver ischemia-reperfusion model

BACKGROUND Mesenchymal stem cells(MSCs)have been used in liver transplantation and have certain effects in alleviating liver ischemia-reperfusion injury(IRI)and regulating immune rejection.However,some studies have indicated that the effects of MSCs are not very significant.Therefore,approaches that enable MSCs to exert significant and stable therapeutic effects are worth further study.AIM To enhance the therapeutic potential of human menstrual blood-derived stromal cells(MenSCs)in the mouse liver ischemia-reperfusion(I/R)model via interferon-γ(IFN-γ)priming.METHODS Apoptosis was analyzed by flow cytometry to evaluate the safety of IFN-γpriming,and indoleamine 2,3-dioxygenase(IDO)levels were measured by quantitative real-time reverse transcription polymerase chain reaction,western blotting,and ELISA to evaluate the efficacy of IFN-γpriming.In vivo,the liver I/R model was established in male C57/BL mice,hematoxylin and eosin and TUNEL staining was performed and serum liver enzyme levels were measured to assess the degree of liver injury,and regulatory T cell(Treg)numbers in spleens were determined by flow cytometry to assess immune tolerance potential.Metabolomics analysis was conducted to elucidate the potential mechanism underlying the regulatory effects of primed MenSCs.In vitro,we established a hypoxia/reoxygenation(H/R)model and analyzed apoptosis by flow cytometry to investigate the mechanism through which primed MenSCs inhibit apoptosis.Transmission electron microscopy,western blotting,and immunofluorescence were used to analyze autophagy levels.RESULTS IFN-γ-primed MenSCs secreted higher levels of IDO,attenuated liver injury,and increased Treg numbers in the mouse spleens to greater degrees than untreated MenSCs.Metabolomics and autophagy analyses proved that primed MenSCs more strongly induced autophagy in the mouse livers.In the H/R model,autophagy inhibitors increased the level of H/R-induced apoptosis,indicating that autophagy exerted protective effects.In addition,primed MenSCs decreased the level of H/R-induced apoptosis via IDO and autophagy.Further rescue experiments proved that IDO enhanced the protective autophagy by inhibiting the mammalian target of rapamycin(mTOR)pathway and activating the AMPK pathway.CONCLUSION IFN-γ-primed MenSCs exerted better therapeutic effects in the liver I/R model by secreting higher IDO levels.MenSCs and IDO activated the AMPK-mTOR-autophagy axis to reduce IRI,and IDO increased Treg numbers in the spleen and enhanced the MenSC-mediated induction of immune tolerance.Our study suggests that IFN-γ-primed MenSCs may be a novel and superior MSC product for liver transplantation in the future.

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.

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.

Pharmacological interventions targeting the microcirculation following traumatic spinal cord injury

Traumatic spinal cord injury is a devastating disorder chara cterized by sensory,motor,and autonomic dysfunction that seve rely compromises an individual's ability to perform activities of daily living.These adve rse outcomes are closely related to the complex mechanism of spinal cord injury,the limited regenerative capacity of central neurons,and the inhibitory environment fo rmed by traumatic injury.Disruption to the microcirculation is an important pathophysiological mechanism of spinal cord injury.A number of therapeutic agents have been shown to improve the injury environment,mitigate secondary damage,and/or promote regeneration and repair.Among them,the spinal cord microcirculation has become an important target for the treatment of spinal cord injury.Drug inte rventions targeting the microcirculation can improve the microenvironment and promote recovery following spinal cord injury.These drugs target the structure and function of the spinal cord microcirculation and are essential for maintaining the normal function of spinal neuro ns,axons,and glial cells.This review discusses the pathophysiological role of spinal cord microcirculation in spinal cord injury,including its structure and histopathological changes.Further,it summarizes the progress of drug therapies targeting the spinal cord mic rocirc ulation after spinal cord injury.

Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury

Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases.

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

AIM: To determine whether Saiko-keishioto (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 ischemia followed by 60 min of reperfusion. Intravital microscopywas used to monitor leukocyte recruitment. Plasma tumor necrosis factor (TNF) levels and alanine aminotransferase (ALT) activities were measured. T]-10 1 gl(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 withT]-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 TL-10 increased plasma nitrite/nitrate levels.CONCLUSION: TJ-10 attenuates the gut I/R-induced hepalJc 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 .

Molecular approaches for spinal cord injury treatment

Injuries to the spinal cord result in permanent disabilities that limit daily life activities.The main reasons for these poor outcomes are the limited regenerative capacity of central neurons and the inhibitory milieu that is established upon traumatic injuries.Despite decades of research,there is still no efficient treatment for spinal cord injury.Many strategies are tested in preclinical studies that focus on ameliorating the functional outcomes after spinal cord injury.Among these,molecular compounds are currently being used for neurological recovery,with promising results.These molecules target the axon collapsed growth cone,the inhibitory microenvironment,the survival of neurons and glial cells,and the re-establishment of lost connections.In this review we focused on molecules that are being used,either in preclinical or clinical studies,to treat spinal cord injuries,such as drugs,growth and neurotrophic factors,enzymes,and purines.The mechanisms of action of these molecules are discussed,considering traumatic spinal cord injury in rodents and humans.

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.

护肝片预防性治疗抗结核药物性肝损伤的Meta分析

目的:评价预防性使用护肝片对anti-TB DILI的有效性和安全性,明确护肝片对anti-TB DILI的预防作用。方法:对6个主要的中文和英文数据库进行了检索,从数据库建立之日起至2021年12月,不限制语言和发表偏倚。两名作者根据纳入和排除标准独立选择合格的研究,然后提取数据并进行Meta分析。结果:本研究共纳入18项研究的4270例患者,Meta分析结果显示预防性使用护肝片与anti-TB DILI发生率降低相关[RR=0.29,95%CI(0.24,0.36),P<0.05],敏感性分析提示结果稳健。预防性服用护肝片在4周内[RR=0.27,95%CI(0.16,0.48),P<0.001]和4周后[RR=0.34,95%CI(0.17,0.66),P=0.001]均可显著降低anti-TB DILI的发生率,且异质性较低。在乙型肝炎表面抗原阳性(HBsAg+)患者中的anti-TB DILI发生率也显著降低[R=0.25,95%CI(0.15,0.39),P<0.001]。结论:在抗结核治疗的患者中预防性使用护肝片可降低anti-TB DILI发生,尤其在HBsAg+的患者中有更多获益。由于纳入研究的方法学质量不高,尚需要更多高质量的研究来进一步验证其有效性和安全性。

中医非药物疗法治疗骨伤术后疼痛临床观察

目的探讨分析中医非药物疗法治疗骨伤术后疼痛的临床效果。方法选择遂川县中医院于2020年1月—2022年1月收治的60例骨伤术后疼痛患者,采取随机数字表法分组,奇数患者纳入观察组(30例),实施中医非药物疗法,偶数患者纳入对照组(30例),实施常规治疗。对比两组临床疗效、焦虑自评量表(SAS)评分、抑郁自评量表(SDS)评分、视觉模拟量表(VAS)评分、生活质量评分以及关节活动度(ROM)等情况。结果观察组临床总有效率为93.33%(28/30),高于对照组的70.00%(21/30)(P<0.05)。治疗后,观察组SAS、SDS、VAS和生活质量评分以及ROM均优于对照组,差异均有统计学意义(P<0.05)。结论应用中医非药物疗法治疗骨伤,可有效缓解患者疼痛以及因疾病产生的焦虑、抑郁等不良情绪,其关节活动度改善明显,生活质量切实提升,值得临床大力推广、应用。

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。

心搏骤停后综合征的治疗方法研究进展

心搏骤停后综合征(PCAS)是心搏骤停的严重并发症,致死、致残率极高。如何采用及时有效的治疗措施提高PCAS患者的救治成功率已成为急诊医学界关注和研究的热点问题之一。目前,PCAS的治疗措施主要包括呼吸支持、循环支持、脑保护、冠状动脉血运重建等。本文对当前PCAS的主要治疗方法进行总述,以期为临床医生救治此类患者和开展进一步的研究提供参考。

急性大血管闭塞性脑卒中桥接治疗后再灌注损伤sCD40L、ET-1、ICAM-1因子相关性研究

目的探讨血清细胞间黏附分子(ICAM-1)、内皮素-1(ET-1)、血浆可溶性CD40配体(sCD40L)与急性大血管闭塞性脑卒中桥接治疗后再灌注损伤的关系。方法选取湖南省脑科医院2021年12月至2022年12月间接受桥接治疗的急性大血管闭塞性脑卒中患者90例。按照术后是否出现再灌注损伤并发症进行分组,分为再灌注损伤组和未再灌注损伤组:运用ELISA法检测桥接治疗前和治疗开始后30 min、1h、2h、6h、24 h、5d的患者血清sCD40L、ICAM-1、ET-1的水平,并分析两组之间的差异以及治疗前后这3种因子水平的变化。结果治疗前再灌注损伤组和未再灌注损伤组患者血清中sCD40L、ICAM-1、ET-1水平比较差异无统计学意义(P>0.05)。未再灌注损伤组患者的治疗前及治疗后30 min、1 h、2h、6h、24 h、5d的血清中sCD40L、ICAM-1、ET-1水平随时间推移的变化急性大血管闭塞性脑卒中桥接治疗后再灌注损伤组患者的血清sCD40L、ICAM-1、ET-1水平增高,并且随时间推移逐渐升高。均不显著(P>0.05),各指标间无差异:再灌注损伤组患者治疗后各时间点血清中sCD40L、ICAM-1、ET-1水平均显著高于治疗前(均P<0.05),且在治疗后30 min、1h、2h、6 h、24 h、5d的时间点,患者血清中sCD40L、ICAM-1、ET-1水平均随时间变化而升高,不同时间亚组间比较差异均有统计学意义(~均P<0.05)。再灌注损伤组患者治疗后各时间点血清中sCD40L、ICAM-1、ET-1水平均高于未再灌注损伤组相同时间点(~均P<0.05)。结论急性大血管闭塞性脑卒中桥接治疗后再灌注损伤组患者的血清sCD40L、ICAM-1、ET-1水平增高,并且5d内随时间推移逐渐升高。