Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization

Background:Polydatin,a glucoside of resveratrol,has shown protective effects against various diseases.However,little is known about its effect on hepatic ischemia-reperfusion(I/R)injury.This study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying mechanism.Methods:After gavage feeding polydatin once daily for a week,mice underwent a partial hepatic I/R procedure.Serum alanine aminotransferase(ALT)/aspartate aminotransferase(AST),hematoxylin-eosin(H&E)and TdT-mediated dUTP nick-end labeling(TUNEL)staining were used to evaluate liver injury.The severity related to the inflammatory response and reactive oxygen species(ROS)production was also investigated.Furthermore,immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in macrophages.Results:Compared with the I/R group,polydatin pretreatment significantly attenuated I/R-induced liver damage and apoptosis.The oxidative stress marker(dihydroethidium fluorescence,malondialdehyde,superoxide dismutase and glutathione peroxidase)and I/R related inflammatory cytokines(interleukin1β,interleukin-10 and tumor necrosis factor-α)were significantly suppressed after polydatin treatment.In addition,the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in vitro.Western blotting showed that polydatin inhibited the pro-inflammatory function of RAW264.7 via down-regulating the NF-κB signaling pathway.Conclusions:Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NFκB signaling.

Research progress of lncRNA and miRNA in hepatic ischemia-reperfusion injury

Background:Hepatic ischemia-reperfusion injury(HIRI)is a common complication of liver surgeries,such as hepatectomy and liver transplantation.In recent years,several non-coding RNAs(nc RNAs)including long non-coding RNAs(lnc RNAs)and micro RNAs(mi RNAs)have been identified as factors involved in the pathological progression of HIRI.In this review,we summarized the latest research on lnc RNAs,mi RNAs and the lnc RNA-mi RNA regulatory networks in HIRI.Data sources:The Pub Med and Web of Science databases were searched for articles published up to December 2021 using the following keywords:“hepatic ischemia-reperfusion injury”,“lnc RNA”,“long noncoding RNA”,“mi RNA”and“micro RNA”.The bibliography of the selected articles was manually screened to identify additional studies.Results:The mechanism of HIRI is complex,and involves multiple lnc RNAs and mi RNAs.The roles of lnc RNAs such as AK139328,CCAT1,MALAT1,TUG1 and NEAT1 have been established in HIRI.In addition,numerous mi RNAs are associated with apoptosis,autophagy,oxidative stress and cellular inflammation that accompany HIRI pathogenesis.Based on the literature,we conclude that four lnc RNA-mi RNA regulatory networks mediate the pathological progression of HIRI.Furthermore,the expression levels of some lnc RNAs and mi RNAs undergo significant changes during the progression of HIRI,and thus are potential prognostic markers and therapeutic targets.Conclusions:Complex lnc RNA-mi RNA-m RNA networks regulate HIRI progression through mutual activation and antagonism.It is necessary to screen for more HIRI-associated lnc RNAs and mi RNAs in order to identify novel therapeutic targets.

HSP110 aggravates ischemia-reperfusion injury after liver transplantation by promoting NF-κB pathway

Background:Ischemia-reperfusion injury(IRI)poses a significant challenge to liver transplantation(LT).The underlying mechanism primarily involves overactivation of the immune system.Heat shock protein 110(HSP110)functions as a molecular chaperone that helps stabilize protein structures.Methods:An IRI model was established by performing LT on Sprague-Dawley rats,and HSP110 was silenced using siRNA.Hematoxylin-eosin staining,TUNEL,immunohistochemistry,ELISA and liver enzyme analysis were performed to assess IRI following LT.Western blotting and quantitative reverse transcription-polymerase chain reaction were conducted to investigate the pertinent molecular changes.Results:Our findings revealed a significant increase in the expression of HSP110 at both the mRNA and protein levels in the rat liver following LT(P<0.05).However,when rats were injected with siRNAHSP110,IRI subsequent to LT was notably reduced(P<0.05).Additionally,the levels of liver enzymes and inflammatory chemokines in rat serum were significantly reduced(P<0.05).Silencing HSP110 with siRNA resulted in a marked decrease in M1-type polarization of Kupffer cells in the liver and downregulated the NF-κB pathway in the liver(P<0.05).Conclusions:HSP110 in the liver promotes IRI after LT in rats by activating the NF-κB pathway and inducing M1-type polarization of Kupffer cells.Targeting HSP110 to prevent IRI after LT may represent a promising new approach for the treatment of LT-associated IRI.

Application and mechanisms of Sanhua Decoction in the treatment of cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion is a process in which the blood supply to the brain is temporarily interrupted and subsequently restored.However,it is highly likely to lead to further aggravation of pathological damage to ischemic tissues or the nervous system.,and has accordingly been a focus of extensive clinical research.As a traditional Chinese medicinal formulation,Sanhua Decoction has gradually gained importance in the treatment of cerebrovascular diseases.Its main constituents include Citrus aurantium,Magnolia officinalis,rhubarb,and Qiangwu,which are primarily used to regulate qi.In the treatment of neurological diseases,the therapeutic effects of the Sanhua Decoction are mediated via different pathways,including antioxidant,anti-inflammatory,and neurotransmitter regu-latory pathways,as well as through the protection of nerve cells and a reduction in cerebral edema.Among the studies conducted to date,many have found that the application of Sanhua Decoction in the treatment of neurological diseases has clear therapeutic effects.In addition,as a natural treatment,the Sanhua Decoction has received widespread attention,given that it is safer and more effective than traditional Western medicines.Consequently,research on the mechanisms of action and efficacy of the Sanhua Decoctions in the treatment of cerebral ischemia-reperfusion injury is of considerable significance.In this paper,we describe the pathogenesis of cerebral ischemia-reperfusion injury and review the current status of its treatment to examine the therapeutic mechanisms of action of the Sanhua Decoction.We hope that the findings of the research presented herein will contribute to a better understanding of the efficacy of this formulation in the treatment of cerebral ischemia-reperfusion,and provide a scientific basis for its application in clinical practice.

Protective Effect of Naringenin on Acute Myocardial Ischemia-reperfusion Injury in Rats

[Objectives]To investigate the protective mechanism of naringenin on acute myocardial ischemia-reperfusion injury(AMI-RI)in Sprague-Dawley(SD)rats.[Methods]A total of 32 SD rats with AMI-RI model construction were randomly divided into AMI-RI model control group and citrus pigment A/B/C groups(n=8).The naringenin A,B,and C groups were administrated 20,40 and 80 mg/(kg•d)for 10 d.The AMI group served as the negative control and was not treated.At the conclusion of the treatment regimen,a sample of intraventricular blood was collected for the purpose of measuring lactate dehydrogenase(LDH),glutathione peroxidase(GLH-PX),nitric oxide(NO),and superoxide dismutase(SOD)levels.Additionally,myocardial tissue was identified within the ischemic region.The content of malondialdehyde(MDA)was determined by inducing nitric oxide synthase(iNOS)and endodermal nitric oxide synthase(eNOS)positive cells in the left anterior descending coronary artery.[Results]Following citrus treatment,the contents of GLH-PX and SOD in ventricular blood of the citrus B group were found to be significantly elevated,while the contents of NO and LDH in myocardial MDA and ventricle were observed to be significantly reduced.The number of eNOS-positive cells was significantly increased,while the number of iNOS-positive cells was significantly decreased.The difference was statistically significant when compared with the AMI-RI group(P<0.05).The changes observed in the above indicators in the citrus C group were more pronounced than those observed in the citrus B group.The difference between the citrus C and the B group was statistically significant(P<0.05),indicating that this effect is concentration dependent.[Conclusions]In addition to its ability to inhibit myocardial lipid peroxidation during AMI-RI by increasing SOD activity,naringenin may also affect the synthesis and release of NO by regulating eNOS and iNOS,thereby achieving protection against AMI-RI.One effect is enhanced as the dose of the drug increases.

Network pharmacology investigation of the mechanism underlying the therapeutic action of Shikang granules in retinal ischemia-reperfusion injuries

Background:Retinal ischemia/reperfusion(I/R)injury often results in vision loss,and effective clinical management options are currently lacking.Shikang granules(SKG)are traditional Chinese medicine-based preparations commonly used in clinical practice for treating optic atrophy.Methods:Despite decades of clinical use,the precise mechanism of action(MoA)of SKG remains elusive.Here,we employ a network pharmacological approach to elucidate its MoA by identifying active ingredients and relevant targets using the Traditional Chinese Medicine System Pharmacology Database and Analytical Platform.Targets associated with retinal I/R injury were sourced from GeneCards,Online Mendelian Inheritance in Man,and DisGeNET.Venny software facilitated the identification of intersecting targets,which were then subjected to gene ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis.To validate the protective effect and explore the MoA of SKG in retinal I/R injuries,we conducted experiments using rat models.Results:Our animal experiments demonstrated that SKG mitigated apoptosis following retinal I/R injury by upregulating the expression of the anti-apoptotic protein Bcl-2 and downregulating the expression of BAX,Caspase-9,Caspase-3,PARP,and cytochrome C.Additionally,SKG was found to increase the expression of PI3K and AKT.Conclusions:SKG may exert its protective effects by inhibiting apoptosis through modulation of pro-apoptotic and anti-apoptotic protein expression,as well as activation of the PI3K/AKT pathway.

Atorvastatin Alleviates Myocardial Ischemia-Reperfusion Injury via miR-26a-5p/FOXO1

Purpose: Ischemia-reperfusion (I/R) injury exacerbates myocardial cell death (including apoptosis and necrosis), leading to complications such as arrhythmias, myocardial stenosis, microvascular obstruction and heart failure, and it is particularly important to seek new strategies to mitigate reperfusion injury. In this paper, we will investigate whether atorvastatin can alleviate myocardial ischemia-reperfusion injury and verify its molecular mechanism. Methods: We successfully constructed a hypoxia-reperfusion (H/R) H9c2 cell model and transfected miR-26a-5p mimic, miR-26a-5p inhibitor and its negative control NC-mimic or NC-inhibitor into H9c2 cells using a transfection kit. The expression of miR-26a-5p and FOXO1 were detected by RT-qPCR assay, the expression of related proteins by Western blot assay, the cell viability of H9c2 cells by CCK-8 assay, the apoptosis rate of H9c2 cells by flow cytometry, the CK and LDH activity in cells by CK and LDH assay kits. The targeting relationship between miR-26a-5p and FOXO1 was verified by dual luciferase reporter gene assay. Results: MiR-26a-5p expression was decreased in H/R-induced cells and FOXO1 expression was increased in H/R-induced cells. Atorvastatin alleviated H/R injury in cardiomyocytes and was most effective at a concentration of 1 μM. Atorvastatin alleviated H/R injury in cardiomyocytes by upregulating miR-26a-5p expression, miR-26a-5p and FOXO1 were negatively regulated by targeting. Conclusion: Atorvastatin can alleviate H/R injury in cardiomyocytes by regulating miR-26a-5p/FOXO1.

硬件损伤条件下无人机辅助的NOMA-IRS网络资源分配算法

探讨了在硬件损伤条件下,如何通过搭载在无人机上的智能反射面(IRS)有效支持基于非正交多址接入(NOMA)技术的网络,以加快多用户数据的传输速率。提出了一种全面优化策略实现整个通信系统的最大传输速率,包括联合调整串行干扰消除的解码策略、IRS的反射配置、无人机的空间位置以及基站的发射功率。由于该问题是一个非凸问题,提出使用块坐标下降方法来实现优化的一种迭代算法,将原始的非凸问题细分为3个子问题,并通过结合惩罚函数法、半正定松弛技术和连续凸近似法来解决这些子问题。仿真结果表明:提出的算法在系统总速率方面相比随机部署无人机、未使用IRS辅助的NOMA策略,系统速率有显著提升。

IRS辅助的车联网相移设计和信道对齐策略

针对车联网中车辆的动态移动以及信号的随机散射所导致的信道快速变化问题,研究了智能反射面(intelligent reflecting surface,IRS)辅助的车联网通信并提出了联合相移设计和信道对齐策略,以削减车联网中多普勒频移的影响并提升通信性能。提出的策略由两个阶段构成。在第一阶段设计IRS的相移以改善级联信道的衰落状态,在策略的第二阶段进行修正函数的设计,实现了直接信道和级联信道的信道对齐,从而减少直接信道快衰落状态对通信性能的影响。通过联合相移设计和信道对齐策略中设计的反射相移以及修正函数,实现了通信性能的提升。仿真结果表明,所提策略相比于相移优化策略可以提升8.8%的频谱效率。

IRS辅助的异构SWIPT-NOMA系统资源分配方案

考虑到未来大型物联网中待服务用户的异构性(接收机产自不同制造商,且具有不同结构、不同功能)和服务需求的多样性,针对功率分割(PS)用户和时间切换(TS)用户共存的异构场景,提出一种IRS辅助的无线携能通信(SWIPT)非正交多址接入(NOMA)通信系统模型。在满足两类用户服务质量的条件下,通过联合优化基站的有源波束成形、IRS的无源相移矩阵、PS用户的功率分割系数、TS用户时间切换系数以及两类用户的串行干扰消除解码顺序来最小化基站的发射功率。为解决该非凸问题,采用基于连续凸逼近的交替迭代方法将问题拆分成多个子问题。针对IRS相移的无源波束成形优化子问题,采用连续秩一约束松弛方法求解。仿真结果表明,IRS辅助的通信系统基站发射功率明显低于无IRS方案;IRS辅助的NOMA通信系统基站发射功率低于IRS辅助的正交多址接入通信系统;IRS辅助的PS-SWIPT系统基站发射功率低于IRS辅助的TS-SWIPT系统。

利用元学习算法的IRS-OTFS通信系统信道估计

针对高多普勒场景下智能反射表面(IRS)辅助多用户通信系统存在的信道估计传输开销大的问题,该文结合正交时频空间(OTFS)调制特点构造一种IRS-OTFS通信系统,充分发挥IRS和OTFS的性能优势,并在此基础上提出一种学习率自适应的模型无关元学习(MAML)算法。对IRS-OTFS多用户信道估计任务做离线训练,根据各任务的收敛速度自适应地调整学习率,防止训练失衡,并利用信道之间的相关性和MAML算法的少样本、泛化特性得到全局模型和适应性模型,快速学习新用户信道的传输特性,降低传输开销,提高信道估计准确性。理论分析和仿真结果表明,该算法在信道传输条件相同的情况下,将传输开销降低了大约50%,并相对于基准算法有4.8 dB左右的性能提升。

IRS辅助去蜂窝mMIMO系统低复杂度波束赋形算法

针对目前智能反射面(intelligent reflecting surface,IRS)辅助去蜂窝大规模多输入多输出(massive multiple-input multiple-output,mMIMO)系统现有算法复杂度高的问题,提出了一种基于IRS辅助去蜂窝mMIMO系统联合波束赋形低复杂度算法。在满足还原用户接收的信号、IRS相移和发射功率约束的条件下,以得到最优发射波束赋形向量为目标,构建了一个联合优化接入点(access point,AP)主动波束赋形和IRS被动波束赋形问题。利用交替优化方法将原问题转换为两个易于处理的子问题,并基于解非齐次线性方程组,采用Lagrange乘数法和人工蜂群算法对子问题进行求解。仿真结果表明,相较于传统算法,所提算法有更低的复杂度和误码率,可使用更小的发射功率和频谱效率等资源获得与其他方案相当的性能。

Protective effects of combined treatment with ciprofol and mild therapeutic hypothermia during cerebral ischemia-reperfusion injury

Despite improvement in cardiopulmonary resuscitation(CPR)performance,cardiac arrest(CA)is still associated with poor prognosis.The high mortality rate is due to multi-organ dysfunction caused by cerebral ischemia and reperfusion injury(I/R).The guidelines for CPR suggest the use of therapeutic hypothermia(TH)as an effective treatment to decrease mortality and the only approach confirmed to reduce I/R injury.During TH,sedative agents(propofol)and analgesia agents(fentanyl)are commonly used to prevent shiver and pain.However,propofol has been associated with a number of serious adverse effects such as metabolic acidosis,cardiac asystole,myocardial failure,and death.In addition,mild TH alters the pharmacokinetics of agents(propofol and fentanyl)and reduces their systemic clearance.For CA patients undergoing TH,propofol can be overdosed,leading to delayed awakening,prolonged mechanical ventilation,and other subsequent complications.Ciprofol(HSK3486)is a novel anesthetic agent that is convenient and easy to administer intravenously outside the operating room.Ciprofol is rapidly metabolized and accumulates at low concentrations after continuous infusion in a stable circulatory system compared to propofol.Therefore,we hypothesized that treatment with HSK3486 and mild TH after CA could protect the brain and other organs.

Improved methodology for efficient establishment of the myocardial ischemia-reperfusion model in pigs through the median thoracic incision

To investigate the feasibility and effectiveness of establishing porcine ischemia-reperfusion models by ligating the left anterior descending(LAD)coronary artery,we first randomly divided 16 male Bama pigs into a sham group and a model group.After anesthesia,we separated the arteries and veins.Subsequently,we rapidly located the LAD coronary artery at the beginning of its first diagonal branch through a mid-chest incision.Then,we loosened and released the ligation line after five minutes of pre-occlusion.Finally,we ligated the LAD coronary artery in situ two minutes later and loosened the ligature 60 min after ischemia.Compared with the sham group,electrocardiogram showed multiple continuous lead ST-segment elevations,and ultrasound cardiogram showed significantly lower ejection fraction and left ventricular fractional shortening at one hour and seven days post-operation in the model group.Twenty-four hours after the operation,cardiac troponin T and creatine kinase-MB isoenzyme levels significantly increased in the model group,compared with the sham group.Hematoxylin and eosin staining showed the presence of many inflammatory cells infiltrating the interstitium of the myocardium in the model group but not in the sham group.Masson staining revealed a significant increase in infarct size in the ischemia/reperfusion group.All eight pigs in the model group recovered with normal sinus heart rates,and the survival rate was 100%.In conclusion,the method can provide an accurate and stable large animal model for preclinical research on ischemia/reperfusion with a high success rate and homogeneity of the myocardial infarction area.

Liqi Huoxue dripping pill protects against myocardial ischemia-reperfusion injury via the PI3K/Akt/GSK-3β signaling pathway in rats

Background:Liqi Huoxue dripping pill(LQHXDP),a traditional Chinese drug for coronary heart disease,has a protective effect on the heart of rats with myocardial ischemia-reperfusion injury(MIRI)in previous studies;however,its mechanism of action remains unclear.The purpose of this study was to investigate the protective mechanism of LQHXDP on MIRI in rats and its relationship with the PI3K/Akt signaling pathway.Methods:In this study,Sprague-Dawley rats were pre-infused with LQHXDP(175 mg/kg/d)for 10 days.PI3K inhibitor LY294002(0.3 mg/kg)was intravenously injected 15 minutes before ischemia.The rat model of MIRI was established by ligating the left anterior descending coronary artery.Subsequently,cardiac hemodynamics,serum myocardial injury markers,inflammatory factors,myocardial infarct size,antioxidant indexes,myocardial histopathology,and phosphorylation levels of key proteins of PI3K/Akt signaling pathway were assessed in rats.Results:LQHXDP was found to improve cardiac hemodynamic indexes,reduce serum creatine kinase MB isoenzyme activity and cardiac troponin and heart-type fatty acid binding protein levels,lower serum interleukin-1 beta,interleukin-6 and tumour necrosis factorαlevels,reduce the myocardial infarct size and enhance the antioxidant capacity of myocardial tissue in MIRI rats.Pathological analysis revealed that LQHXDP attenuated the extent of myocardial injury and protected mitochondria from damage in MIRI rats.Immunoblot analysis revealed that LQHXDP increased the expression levels of p-Akt and p-GSK-3βin MIRI rat cardiomyocytes.PI3K inhibitor LY294002 could impair these effects of LQHXDP.Conclusion:LQHXDP attenuated myocardial injury,attenuated oxidative stress injury and reduced inflammatory response in MIRI rats,and its protective effects were mediated by activating of PI3K/Akt/GSK-3βsignaling pathway.

Heat shock pretreatment improves stem cell repair following ischemia-reperfusion injury via autophagy

AIM: To investigate whether heat shock pretreatment(HSP) improves mesenchymal stem cell(MSC) repair via autophagy following hepatic ischemia-reperfusion injury(HIRI).METHODS: Apoptosis of MSCs was induced by 250 m M hydrogen peroxide(H2O2) for 6 h. HSP was carried out using a 42 ℃ water bath for 1, 2 or 3 h. Apoptosis of MSCs was analyzed by flow cytometry, and Western blot was used to detect Bcl-2, Bax and cytochrome C expression. Autophagy of MSCs was analyzed by flow cytometry and transmission electron microscopy, and the expression of beclin Ⅰ?and LC3-Ⅱ was detected by Western blot. MSCs were labeled in vivo with the fluorescent dye, CM-Dil, and subsequently transplanted into the portal veins of rats that had undergone HIRI. Liver levels of proliferating cell nuclear antigen(PCNA) were quantified by fluorescent microscopy. Serum aminotransferase activity and the extent of HIRI were also assessed at each time point.RESULTS: HSP for 2 h reduced apoptosis of MSCs induced by H2O2 as seen by a decrease in apoptotic rate, a decrease in Bax and cytochrome C expression and an increase in Bcl-2 expression(P < 0.001). In addition, HSP for 2 h induced autophagy of MSCs exposed to H2O2 as shown by an increase in acidic vesicular organelle-positive cells, beclin 1 and LC3-Ⅱ expression, and autophagosome formation(P < 0.05). Treatment with 3-methyladenine attenuated HSPinduced autophagy and abolished the protective effects of HSP on the apoptosis of MSCs. Rapamycin failed to have additional effects on either autophagy or apoptosis compared with HSP alone. The phosphorylation of p38 MAPK was significantly elevated and the phosphorylation of m TOR was downregulated in heat shock pretreated MSCs. Treatment with the p38 MAPK inhibitor, SB203580, reduced HSP-induced autophagy in MSCs. In vivo studies showed that the transplantation of HSP-MSCs resulted in lower serum aminotransferase levels, lower Suzuki scores, improved histopathology and an increase in PCNA-positive cells(P < 0.05).CONCLUSION: HSP effectively induces autophagy following exposure to H2O2 via the p38MAPK/m TOR pathway, which leads to enhanced MSC survival and improved MSC repair following HIRI in rats.

高性能Ir基阳极双催化层阴离子交换膜电解水

设计高性能低Ir阳极催化层对阴离子交换膜电解水(AEMWE)商业化发展至关重要。本研究采用催化剂涂覆基底(CCS)方法,构建基于氧化铱(IrO_(2))和碳载铱(IrC)双催化层的阳极结构,提出了一种新型双Ir催化层并提高了AEMWE性能。研究表明,在IrC-IrO_(2)(先喷涂碳载铱,后喷涂氧化铱)催化层中,IrC高度分散特性有利于提高催化层中Ir的利用率,优化了催化层内电子、氢氧根离子的传输。采用商业Pt/C催化剂作为阴极,IrC-IrO_(2)阳极双催化层组装成碱性膜电极,在1 mol/L KOH电解质条件下,2.0 V时IrC-IrO_(2)电极达到了2.31 A/cm^(2)的高电流密度,而且在低浓度电解质以及纯水中依旧保持较高的性能。本研究为碱性膜电解水技术高效催化层的设计提供了参考。

Recombinant adenovirus vector Ad-hIL-10 protects grafts from cold ischemia-reperfusion injury following orthotopic liver transplantation in rats

BACKGROUND: Interleukin 10 (IL-10), a Th2 type cytokine, modulates inflammatory responses by inhibiting the production of proinflammatory cytokines. This study was designed to investigate the protective effects of adenovirus-mediated human IL-10 (Ad-hIL-10) gene transfer on protecting grafts from cold ischemia-reperfusion injury following orthotopic liver transplantation in rats. METHODS: Adenoviruses encoding hIL-10 or beta-galactosidase (Ad-lacZ) were injected via the superior mesenteric vein into prospective donor animals. The donor liver was harvested 48 hours after transduction, and stored for 12 hours at 4 degrees C in lactated Ringer's solution prior to transplantation. The rats were divided into saline, Ad-lacZ, and Ad-hIL-10 groups. Liver function test, histopathological examination, reverse transcriptase-polymerase chain reaction (RT-PCR), and Western blotting were performed at 24 hours after transplantation in the three groups. RESULTS: Liver function (ALT and AST) was significantly improved, and the Suzuki score was significantly decreased in the Ad-hIL-10 group. The levels of hepatic TNF-alpha, MIP-2, ICAM-1 mRNA, and NF-kappa B protein in the Ad-hIL-10 group were significantly decreased. The expression of hIL-10 mRNA was detected by RT-PCR in Ad-hIL-10-treated grafts but not in controls treated with saline or Ad-lacZ. CONCLUSIONS: Donor pretreatment with Ad-hIL-10 down-regulates the expression of proinflammatory cytokines TNF-alpha, MIP-2, and ICAM-1 mRNA. hIL-10 protects against hepatic cold ischemia-reperfusion injury, at least in part, by suppressing NF-kappa B activation and subsequent expression of proinflammatory mediators. (Hepatobiliary Pancreat Dis Int 2010; 9: 144-148)

Role of sirtuins in ischemia-reperfusion injury

Ischemia-reperfusion injury(IRI)remains an unresolved and complicated situation in clinical practice,especially in the case of organ transplantation.Several factors contribute to its complexity;the depletion of energy during ischemia and the induction of oxidative stress during reperfusion initiate a cascade of pathways that lead to cell death and finally to severe organ injury.Recently,the sirtuin family of nicotinamide adenine dinucleotide-dependent deacetylases has gained increasing attention from researchers,due to their involvement in the modulation of a wide variety of cellular functions.There are seven mammalian sirtuins and,among them,the nuclear/cytoplasmic sirtuin 1(SIRT1)and the mitochondrial sirtuin 3(SIRT3)are ubiquitously expressed in many tissue types.Sirtuins are known to play major roles in protecting against cellular stress and in controlling metabolic pathways,which are key processes during IRI.In this review,we mainly focus on SIRT1 and SIRT3 and examine their role in modulating pathways against energy depletion during ischemia and their involvement in oxidative stress,apoptosis,microcirculatory stress and inflammation during reperfusion.We present evidence of the beneficial effects of sirtuins against IRI and emphasize the importance of developing new strategies by enhancing their action.

Hepatocyte apoptosis induced by hepatic ischemia-reperfusion injury in cirrhotic rats

OBJECTIVE: To investigate whether hepatocyte apoptosis in hepatic ischemia-reperfusion (I/R) injury is mediated by Fas pathway. METHODS: Fas-mRNA expression detected by in situ hybridization assay, caspase-3 activity measured by fluorescence spectrophotometer, and hepatocyte apoptosis detected by TUNEL assay were compared in different L/R conditions between cirrhotic and normal rats. The relationship was analyzed between hepatocyte apoptosis, Fas-mRNA expression, and caspase-3 activity. RESULTS: In cirrhotic rats, Fas-mRNA expression and caspase-3 activity were significantly increased when the ischemic time prolonged, and subsequently, hepatocyte apoptosis was increased (P<0.O1). Under the same I/R condition, the Fas-mRNA expression, caspase-3 activity and hepatocyte apoptosis in cirrhotic liver were significantly higher than those in normal liver (P<0.O1). CONCLUSIONS: Hepatocyte apoptosis in hepatic I/R injury might be mediated by Fas pathway. The possible underlying mechanism that cirrhotic liver is more sensitive to ischemic injury than normal liver is alteration of Fas expression level.