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Background: Clinically, ischemic reperfusion injury is the main cause of stroke injury. This study aimed to assess the effectiveness of fingolimod in suppressing inflammation caused by ischemic brain injury and explore its pharmacological mechanisms. Methods: In total, 75 male Sprague-Dawley rats were randomly and equally assigned to five distinct groups: sham, middle cerebral artery occlusion/ reperfusion (MCAO/R) surgery, fingolimod low-dose (F-L), fingolimod medium-dose (F-M), and fingolimod high-dose (F-H). Neurobehavioral tests, 2,3,5-triphenyltetrazolium chloride staining, and the brain tissue drying-wet method were conducted to evaluate neurological impairment, cerebral infarction size, and brain water content. Enzyme-linked immunosorbent assay was employed to quantify pro-inflammatory cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) protein levels. Western blotting and immunohistochemical staining were performed to assess high mobility group box 1 (HMGB1), toll-like receptor 4 (TLR4), and nuclear factor kappa-B p65 (NF-κBp65) levels. Results: Rats in the F-L, F-M, and F-H groups exhibited lower Longa scores, reduced infarction volumes, and decreased brain edema than those in the MCAO/R group. Additionally, the F-L, F-M, and F-H groups exhibited lower serum levels of IL-1β, IL-6, and TNF-α than those of the MCAO/R group. Additionally, F-L, F-M, and F-H treatments resulted in decreased HMGB1, TLR4, and NF-κBp65 protein expression levels in the hippocampus of MCAO/R rats. Conclusions: Fingolimod was found to reduce ischemic brain injury in a dose-dependent manner. Moreover, it was also found to alleviate inflammation following ischemic brain injury via the HMGB1/TLR4/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

This study explores the neuroprotective effects of neuropeptide FF (NPFF, FLFQPQRFamide) in the context of ischemic injury. Based on transcriptomic analysis in stroke models treated with 5-Aza-dC and task-specific training, we identified significant gene expression changes, particularly involving NPFF. To further explore NPFF's role in promoting neuronal recovery, recombinant NPFF protein (rNPFF) was used in primary mixed cortical cultures subjected to oxygen-glucose deprivation and reoxygenation. Our results demonstrated that rNPFF significantly reduced lactate dehydrogenase release, indicating decreased cellular damage. It also significantly increased the expression of TUJ1 and MAP2, markers of neuronal survival and dendritic integrity. Additionally, rNPFF significantly upregulated key synaptic proteins, including GAP43, PSD95, and synaptophysin, which are essential for synaptic repair and plasticity. Post-injury rNPFF treatment led to a significant upregulation of pro-brain-derived neurotrophic factor (BDNF) and mature BDNF, which play critical roles in neuronal survival, growth, and synaptic plasticity. Moreover, rNPFF activated the protein kinase Cε isoform, Sirtuin 1, and peroxisome proliferator-activated receptor gamma pathways, which are crucial for regulating cellular stress responses, synaptic plasticity, and energy homeostasis, further promoting neuronal survival and recovery. These findings suggest that rNPFF may play a pivotal role in enhancing neuronal survival and synaptic plasticity after ischemic injury, highlighting its potential as a therapeutic target for stroke recovery. [ABSTRACT FROM AUTHOR]

Extremity trauma, including ischemia (e.g., prolonged tourniquet application or crush), is common among battlefield injuries. Injured muscle releases toxins leading to rhabdomyolysis and, potentially, acute kidney injury (AKI). The goal of this study was to characterize sequelae of ischemic extremity injury over 72 h, focusing on time courses of rhabdomyolysis and AKI. Male Sprague Dawley rats were placed into two groups. Ischemic injury was produced in anesthetized rats using bilateral tourniquets (TK; n = 10) for 5 h; control (CON; n = 9) rats were treated identically without TK application. Indicators of rhabdomyolysis and renal function were measured in conscious rats 1 day preinjury (baseline, BL) and then at 1.5, 24, 48, and 72 h post-TK release. Prolonged TK application produced necrosis in both muscle and bone marrow but not in kidney. The wet/dry weights indicated edema in injured limbs at 72 h (4.1 (0.5) (TK) vs. 2.9 (0.1) (CON); p < 0.001). TK rats exhibited a 100-fold increase in creatine kinase activity compared to CON at 1.5 h (20,040 (7265) U/L vs. 195 (86) U/L (mean (SD); p < 0.0001). TK decreased the mean glomerular filtration rate (GFR; p < 0.001) at 1.5 h, but these values recovered by 24 h in concert with elevated urinary flow and alkalinization. Prolonged ischemic extremity injury therefore produced severe rhabdomyolysis without irreversible renal damage. [ABSTRACT FROM AUTHOR]

Ischemic injury causes dynamic damage to the native extracellular matrix (ECM), which plays a key role in tissue homeostasis and regeneration by providing structural support, facilitating force transmission, and transducing key signals to cells. The main approach aimed at repairing injury to ischemic tissues is restoration of vascular function. Due to their potential to form capillary niches, endothelial cells (ECs) are of greatest interest for vascular regeneration. Integrin binding to ECM is crucial for cell anchorage to the surrounding matrix, spreading, migration, and further activation of intracellular signaling pathways. In this study, we proposed to establish an in-situ engineering strategy to remodel the ECM at the ischemic site to guide EC endogenous binding and establish effective EC/ECM interactions to promote revascularization. We designed and constructed a dual-function molecule (LXW7)2-SILY, which is comprised of two functional domains: the first one (LXW7) binds to integrin αvβ3 expressed on ECs, and the second one (SILY) binds to collagen. In vitro, we confirmed (LXW7)2-SILY improved EC adhesion and survival. After in situ injection, (LXW7)2-SILY showed stable retention at the injured area and promoted revascularization, blood perfusion, and tissue regeneration in a mouse hindlimb ischemia model. Highlights: • A dual-function peptide developed for in-situ engineering native extracellular matrix. • The dual-function peptide specifically anchors endogenous endothelial cells to extracellular matrix. • The dual-function peptide promotes vascularized tissue regeneration. [ABSTRACT FROM AUTHOR]

AIM: To investigate the features of retinal ischemic injuries in a novel mouse model with bilateral carotid artery stenosis (BCAS). METHODS: BCAS was induced with microcoil implantation in 6-8-week-old C57BL6 mice. Cerebral blood flow was monitored at 2, 7, and 28d postoperatively. Retinal morphological changes were evaluated by fundus photography and hematoxylin-eosin staining. Fluorescein fundus angiography (FFA) was performed to detect retinal vascular changes and circulation. The levels of apoptosis, activation of neurogliosis, and expression of hypoxia-inducible factor (HIF)-1α in the retina were assessed by Western blotting and immunofluorescence staining, followed by retinal ganglion cell (RGC) density detection. Additionally, electrophysiological examinations including photopic negative response (PhNR) was also performed. RESULTS: The mice demonstrated an initial rapid decrease in cerebral blood flow, followed by a 4-week recovery period after BCAS. The ratio of retinal artery and vein was decreased under fundus photography and FFA. Compared with the sham mice, BCAS mice showed thinner retinal thickness on day 28. Additionally, apoptosis was increased and RGC density was decreased mainly in peripheral retinal region. Neurogliosis was mainly located in the inner retinal layers, with a stable increase in HIF-1α expression. The dark-adapted electroretinogram showed a notable reduction in the a-, b-, and oscillatory potential (OP) wave amplitudes between days 2 and 7; this gradually recovered over the following 4wk. However, the b- and OP-wave amplitudes were still significantly decreased on PhNR examination on day 28. CONCLUSION: BCAS can result in relatively mild retinal ischemia injuries in mice, mainly in the inner layer and peripheral region. Our study provides a novel animal model for investigating retinal ischemic diseases.

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations (microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

Liver transplantation remains the only definitive treatment for end-stage liver diseases. However, the increasing prevalence of fatty liver disease among potential donors exacerbates the shortage of suitable organs. This study evaluates the efficacy of the preservation solution Institut Georges Lopez-2 (IGL-2) compared to Histidine–Tryptophan–Ketoglutarate (HTK) and University of Wisconsin (UW) preservation solutions in mitigating ischemia-reperfusion injury (IRI) in steatotic livers. Using Zucker Obese rat livers, we assessed the impact of 24-h static cold storage (SCS) with each solution on transaminase release, glutathione redox balance, antioxidant enzyme activity, lipoperoxidation, and inflammation markers. IGL-2 and UW solutions demonstrated reduced transaminase and lactate levels compared to HTK, indicating better preservation of liver integrity. IGL-2 maintained a higher reduced glutathione/oxidized glutathione (GSH/GSSG) ratio, suggesting more effective management of oxidative stress. Antioxidant enzyme activities catalase, superoxide dismutase, and glutathione peroxidase (CAT, SOD, GPX) were higher in IGL-2 preserved livers, contributing to decreased oxidative damage. Lipid peroxidation markers and inflammatory markers were lower in IGL-2 than in HTK, indicating reduced oxidative stress and inflammation. Additionally, improved mitochondrial function was observed in the IGL-2 group, correlating with reduced reactive oxygen species (ROS) production and lipid peroxidation. These findings suggest that IGL-2 offers superior preservation of liver viability, reduces oxidative stress, and minimizes inflammation compared to HTK and UW solutions. By maintaining a higher ratio of reduced glutathione and antioxidant enzyme activity, IGL-2 effectively mitigates the harmful effects of ischemia-reperfusion injury. The reduced lipid peroxidation and inflammation in the IGL-2 group further underscore its potential in improving liver transplant outcomes. These results highlight the importance of optimizing preservation solutions to enhance the viability and functionality of donor organs, potentially expanding the donor pool and improving the success rates of liver transplantation. Future research should focus on refining preservation techniques and exploring additional protective agents to further improve organ preservation and transplant outcomes. [ABSTRACT FROM AUTHOR]

目的 分析缺血对视网膜神经节细胞（retinal ganglion cells，RGCs）凋亡过程中内质网应激（endoplasmic reticulum stress，ERS）相关蛋白葡萄糖调节蛋白78（glucose regulated protein78，GRP78）、增强子结合蛋白同源蛋白（C/BEBP homologous protein，CHOP）、半胱氨酸天冬氨酸蛋白酶（cysteinyl aspartate specific proteinase，Caspase）-12表达的影响，探究缺血性视网膜损伤（ischemic retinal injury，IRI）致RGCs凋亡的分子水平发病机制，为预防和治疗IRI提供新的思路和方法。 方法 应用前房高眼压法制作大鼠右眼IRI模型。健康雄性SD大鼠40只，按照缺血时间的不同分为正常对照组、IRI 30 min组、IRI 60 min组以及IRI 120 min组,每组各10只。应用苏木精-伊红（hematoxylin-eosin，HE）染色法观察不同分组中大鼠视网膜组织形态学变化；应用免疫组织化学（immunohistochemical，IHC）染色法观察不同分组中细胞凋亡相关因子B细胞原癌基因-2（B-cell lymphocyte/leukemia-2，Bcl-2）、Bcl-2关联X蛋白（Bcl-2 associated X protein，Bax）和Caspase-3的表达及定位情况；应用免疫荧光（immunofluorescence，IF）染色法观察不同分组中ERS相关蛋白GRP78、CHOP和Caspase-12的表达及定位情况。 结果 HE染色结果显示，与正常对照组相比，IRI各组可见视网膜水肿，视网膜内层厚度增加，视网膜细胞分布紊乱，RGCs数量减少，空泡组织增多。IHC染色结果显示，正常对照组视网膜中仅有少量Bax、Caspase-3蛋白表达，IRI各组中Bax、Caspase-3蛋白主要表达于神经节细胞层和内核层，与正常对照组相比，IRI各组视网膜中Bax、Caspase-3蛋白表达量明显增加，且IRI各组间差异也具有统计学意义。正常对照组视网膜神经节细胞层和内核层中可见大量Bcl-2蛋白表达，与正常对照组相比，IRI各组视网膜中Bcl-2蛋白表达量明显减少，且IRI各组间差异具有统计学意义。IF染色结果显示，正常对照组视网膜中GRP78、CHOP、Caspase-12阳性表达较少，与正常对照组相比，IRI各组视网膜神经节细胞层和内核层中GRP78、CHOP、Caspase-12阳性表达均显著增多，且差异有统计学意义。 结论 IRI可诱导视网膜发生细胞凋亡，其机制可能与ERS相关通路激活有关。 Abstract: Objective To analyze the effects of ischemia on the expression of endoplasmic reticulum stress (ERS)-related proteins glucose regulated protein78 (GRP78), C/BEBP homologous protein (CHOP), and cysteinyl aspartate specific proteinase (Caspase)-12 during the apoptotic process of retinal ganglion cells (RGCs), and to investigate the molecular level pathogenesis of ischemic retinal injury (IRI)-induced RGCs apoptosis, to provide a new idea and method for the prevention and treatment of IRI. Methods The anterior chamber high intraocular pressure method was applied to produce a rat right eye IRI model. Forty healthy male SD rats were randomly divided into the normal control group, 30-min IRI group, 60-min IRI group, and 120-min IRI group according to the ischemic time, with 10 rats in each group. Hematoxylin-eosin (HE) staining was applied to observe the changes in retinal histomorphology in different groups of rats; immunohistochemical (IHC) staining was applied to observe the expression and localization of apoptosis-related factors such as B-cell lymphocyte/leukemia-2 (Bcl-2), Bcl-2 associated X protein (Bax), and Caspase-3 in different groups; immunofluorescence (IF) staining was applied to observe the expression and localization of ERS-related proteins such as GRP78, CHOP and Caspase-12 in other groups. Results HE staining results showed that compared with the normal control group, retinal edema, increased thickness of the inner retinal layer, disturbed distribution of retinal cells, decreased number of RGCs, and increased vacuolar tissues were observed in the IRI groups. IHC staining results showed that only a small amount of Bax and Caspase-3 proteins were expressed in the retina of the normal control group, while Bax and Caspase-3 proteins were mainly expressed in the ganglion cell layer and the inner nuclear layer of the retina in the IRI groups. The expression of Bax and Caspase-3 proteins in the retina of the IRI groups was significantly higher than that of the normal control group, and the differences between the IRI groups were also statistically significant. A large amount of Bcl-2 protein was observed in the ganglion cell layer and inner nuclear layer of the retina in the normal control group. Compared to the normal control group, the expression of Bcl-2 protein in the retina of each IRI group was significantly reduced, and the differences between the IRI groups were also statistically significant. The results of IF staining showed that the positive expressions of GRP78, CHOP, and Caspase-12 in the retina of the normal control group were small, while their expressions in the ganglion cell layer and the inner nuclear layer in the retina of the IRI groups were significantly increased compared with the normal control group. Conclusions IRI can induce apoptosis in the retinal cells, and its mechanism may be related to the activation of ERS-related pathways.

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Abstract Inherited, age-related, and acute retinal diseases are often exacerbated by an aberrant or excessive activity of the complement system. Consequently, cells not directly affected by an acute event or genetic variants may degenerate, resulting in enhanced visual impairment. The therapeutic potential of supplementation of complement factor H (FH), a key regulator of the complement cascade, is therefore particularly promising in the context of retinal diseases caused by complement activation. In this study, we engineered adeno-associated viruses (AAVs) containing sequences of two truncated human FH variants. The expression of these variants was regulated by the glial fibrillary acidic protein (GFAP) promoter, which is selectively active in gliotic Müller cells. Both FH variants consisted of FH domains 19-20, which were connected to domains 1–4 and 1–7, respectively, by a polyglycine linker. These AAVs were intravitreally injected following ischemic injury of C57BL/6J mouse retinas. We observed transgene expression in gliotic Müller cells and to some extent in astrocytes. The expression correlated directly with damage severity. Interventions resulted in decreased complement activation, accelerated normalization of microglia activity and morphological improvements. Reduced levels of C3 transcripts and C3d protein in conjunction with higher transcript levels of inhibitory regulators like Cfi and Cfh, hinted at attenuated complement activity. This study demonstrates the great potential of complement regulatory gene addition therapy. With further in vivo testing it could be applied to treat a wide range of retinal diseases where no causative therapies are available.

Extremity trauma, including ischemia (e.g., prolonged tourniquet application or crush), is common among battlefield injuries. Injured muscle releases toxins leading to rhabdomyolysis and, potentially, acute kidney injury (AKI). The goal of this study was to characterize sequelae of ischemic extremity injury over 72 h, focusing on time courses of rhabdomyolysis and AKI. Male Sprague Dawley rats were placed into two groups. Ischemic injury was produced in anesthetized rats using bilateral tourniquets (TK; n = 10) for 5 h; control (CON; n = 9) rats were treated identically without TK application. Indicators of rhabdomyolysis and renal function were measured in conscious rats 1 day preinjury (baseline, BL) and then at 1.5, 24, 48, and 72 h post-TK release. Prolonged TK application produced necrosis in both muscle and bone marrow but not in kidney. The wet/dry weights indicated edema in injured limbs at 72 h (4.1 (0.5) (TK) vs. 2.9 (0.1) (CON); p < 0.001). TK rats exhibited a 100-fold increase in creatine kinase activity compared to CON at 1.5 h (20,040 (7265) U/L vs. 195 (86) U/L (mean (SD); p < 0.0001). TK decreased the mean glomerular filtration rate (GFR; p < 0.001) at 1.5 h, but these values recovered by 24 h in concert with elevated urinary flow and alkalinization. Prolonged ischemic extremity injury therefore produced severe rhabdomyolysis without irreversible renal damage.

Emerging evidence suggests that stem cell‐derived extracellular vesicles (EVs) may induce pro‐regenerative effects in ischemic tissues by delivering bioactive molecules, including microRNAs. Recent studies have also shown pro‐regenerative benefits of EVs derived from induced pluripotent stem (iPS) cells. However, the underlying mechanisms of EV benefits and the role of their transferred regulatory molecules remain incompletely understood. Accordingly, we investigated the effects of human iPS‐derived EVs (iPS‐EVs) enriched in proangiogenic miR‐126 (iPS‐miR‐126‐EVs) on functional properties of human endothelial cells (ECs) in vitro. We also examined the outcomes following EV injection in a murine model of limb ischemia in vivo. EVs were isolated from conditioned media from cultures of unmodified and genetically modified human iPS cells overexpressing miR‐126. The iPS‐miR‐126‐EVs were enriched in miR‐126 when compared with control iPS‐EVs and effectively transferred miR‐126 along with other miRNAs to recipient ECs improving their functional properties essential for ischemic tissue repair, including proliferation, metabolic activity, cell survival, migration, and angiogenic potential. Injection of iPS‐miR‐126‐EVs in vivo in a murine model of acute limb ischemia promoted angiogenesis, increased perfusion, and enhanced functional recovery. These observations corresponded with elevated expression of genes for several proangiogenic factors in ischemic tissues following iPS‐miR‐126‐EV transplantation. These results indicate that innate pro‐regenerative properties of iPS‐EVs may be further enhanced by altering their molecular composition via controlled genetic modifications. Such iPS‐EVs overexpressing selected microRNAs, including miR‐126, may represent a novel acellular tool for therapy of ischemic tissues in vivo. [ABSTRACT FROM AUTHOR]

Endothelial integrity is critical in mitigating a vicious cascade of secondary injuries following acute ischemic stroke (AIS). Matrix metalloproteinase-9 (MMP-9), a contributor to endothelial integrity loss, is elevated during stroke and is associated with worsened stroke outcome. We investigated the FDA-approved selective sphingosine-1-phosphate receptor 1 (S1PR1) ligand, ozanimod, on the regulation/activity of MMP-9 as well as endothelial barrier components [platelet endothelial cell adhesion molecule 1 (PECAM-1), claudin-5, and zonula occludens 1 (ZO-1)] in human brain microvascular endothelial cells (HBMECs) following hypoxia plus glucose deprivation (HGD). We previously reported that S1PR1 activation improves HBMEC integrity; however, mechanisms underlying S1PR1 involvement in endothelial cell barrier integrity have not been clearly elucidated. We hypothesized that ozanimod would attenuate an HGD-induced increase in MMP-9 activity that would concomitantly attenuate the loss of integral barrier components. Male HBMECs were treated with ozanimod or vehicle and exposed to 3 h of normoxia (21% O2) or HGD (1% O2). Immunoblotting, zymography, qRT-PCR, and immunocytochemical labeling techniques assessed processes related to MMP-9 and barrier markers. We observed that HGD acutely increased MMP-9 activity and reduced claudin-5 and PECAM-1 levels, and ozanimod attenuated these responses. In situ analysis, via PROSPER, suggested that attenuation of MMP-9 activity may be a primary factor in maintaining these integral barrier proteins. We also observed that HGD increased intracellular mechanisms associated with augmented MMP-9 activation; however, ozanimod had no effect on these select factors. Thus, we conclude that ozanimod has the potential to attenuate HGD-mediated decreases in HBMEC integrity in part by decreasing MMP-9 activity as well as preserving barrier properties. [ABSTRACT FROM AUTHOR]

Myocardial infarction (MI) accounts for a significant proportion of death and morbidity in aged individuals. The risk for MI in females increases as they enter the peri-menopausal period, generally occurring in middle-age. Cytochrome (CYP) 450 metabolizes N-3 and N-6 polyunsaturated fatty acids (PUFA) into numerous lipid mediators, oxylipids, which are further metabolised by soluble epoxide hydrolase (sEH), reducing their activity. The objective of this study was to characterize oxylipid metabolism in the left ventricle (LV) following ischemic injury in females. Human LV specimens were procured from female patients with ischemic cardiomyopathy (ICM) or non-failing controls (NFC). Female C57BL6 (WT) and sEH null mice averaging 13-16 months old underwent permanent occlusion of the left anterior descending coronary artery (LAD) to induce myocardial infarction. WT (wild type) mice received vehicle or sEH inhibitor, trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-benzoic acid (tAUCB), in their drinking water ad libitum for 28 days. Cardiac function was assessed using echocardiography and electrocardiogram. Protein expression was determined using immunoblotting, mitochondrial activity by spectrophotometry, and cardiac fibre respiration was measured using a Clark-type electrode. A full metabolite profile was determined by LC-MS/MS. sEH was significantly elevated in ischemic LV specimens from patients, associated with fundamental changes in oxylipid metabolite formation and significant decreases in mitochondrial enzymatic function. In mice, pre-treatment with tAUCB or genetic deletion of sEH significantly improved survival, preserved cardiac function, and maintained mitochondrial quality following MI in female mice. These data indicate that sEH may be a relevant pharmacologic target for women with MI. Although future studies are needed to determine the mechanisms, in this pilot study we suggest targeting sEH may be an effective strategy for reducing ischemic injury and mortality in middle-aged females.

Ischemia–reperfusion (I/R) injury is a common pathophysiological condition in ischemic stroke, involving various pathophysiological events, such as inflammation, cytotoxicity, neuronal loss and disruption of the blood–brain barrier (BBB). Rosavin is the major bioactive ingredient of Rhodiola Rosea L. with multiple therapeutic effects. The purpose of this was to investigate the role of rosavin in I/R‐induced cerebral injury. A cell oxygen–glucose deprivation and reoxygenation (OGD/R) model and a mouse middle cerebral artery occlusion (MCAO) model were established to induce I/R injury in vitro and in vivo, respectively. MCAO‐treated mice and OGD/R‐challenged human brain microvascular endothelial cells (HBMVECs) were administrated with or without rosavin at various concentrations. Rosavin‐treated mice showed reduced infarct volume, neuronal loss and neuronal cytotoxicity in I/R‐injured brains. Rosavin treatment downregulated the expression of pro‐inflammatory cytokines, reduced apoptosis and inhibited the activation of nuclear factor κ B in I/R‐injured mice and HBMVECs. Administration with rosavin also alleviated mouse brain oedema and upregulated tight junction proteins in mouse brains after I/R injury, suggesting that rosavin protected mice against I/R‐induced BBB disruption. Further analysis revealed that rosavin reduced the BBB permeability in I/R‐injured mice and HBMVECs by inhibiting autophagy. Moreover, rosavin intervention inhibited I/R injury‐induced activation of the mitogen‐activated protein kinase (MAPK) pathway and upregulation of matrix metalloproteinases in both mouse and cell models. In conclusion, rosavin protects the BBB against I/R injury possibly by regulating the MAPK pathway. The above results provide a rationale for further exploration of rosavin as a therapeutic candidate for cerebral I/R injury. [ABSTRACT FROM AUTHOR]

Abstract Background Tourniquets provide better tissue visibility during arthroscopic surgery. However, multiple postoperative adverse events associated with ischemia may be caused by excessive inflation pressure and duration. We aimed to evaluate the degree of tourniquet-induced ischemia using a noninvasive continuous real-time monitoring method and the relationship between changes in tissue oxygen saturation (StO2) and blood biochemical markers of ischemic injuries in patients undergoing arthroscopic knee surgery. Methods This was a prospective observational study using near-infrared spectroscopy (NIRS). Data were collected from 29 consecutive patients who underwent arthroscopic procedures. Twenty-five patients underwent anterior cruciate ligament reconstruction, and four underwent meniscal repair. We investigated tourniquet‐induced changes in StO2, monitored using NIRS, and blood biochemical markers of ischemic injuries. Results A significant decrease in the mean StO2 from the baseline was observed during tourniquet inflation in the operative legs. The average decrease in the mean StO2 was 58%. A comparison of mean StO2 between the nonoperative and operative legs before tourniquet deflation showed that mean values of StO2 in the operative legs were significantly lower than those in the nonoperative legs. No significant clinical relationships were observed between changes in StO2 and blood biochemical markers of ischemic injuries (creatine kinase) (p = 0.04, r = 0.38) or tourniquet duration (p = 0.05, r = 0.366). Conclusions Our results demonstrated that StO2 could be used to evaluate tissue perfusion in real time but did not support the hypothesis that StO2 is a useful method for predicting the degree of tourniquet-induced injury during arthroscopic knee surgery.

Cerebral ischemic stroke is one of the leading causes of death and disability worldwide. 2′-fucosyllactose (2′-FL), a human milk oligosaccharide, exerts anti-inflammatory effects and plays a protective role in arterial thrombosis; however, its role in ischemic stroke remains unclear. This study aimed to investigate the neuroprotective effects of 2′-FL and its potential mechanisms in a mouse model of ischemic stroke. Neurological score and behavior tests revealed that 2′-FL promoted the recovery of neurological deficits and motor function in middle cerebral artery occlusion (MCAO) mice, and that 2′FL led to a reduction in the size of cerebral infarct. Biochemical studies showed that administration of 2′-FL led to a reduction of reactive oxygen species (ROS)-related products in the brain of MCAO mice. 2′-FL upregulated IL-10 and downregulated TNF-α level. In addition, 2′-FL enhanced M2-type microglial polarization and upregulated CD206 expression at 7 days after MCAO. At 3 days after MCAO, 2′-FL increased IL-4 levels and activated STAT6. Our data show that 2′-FL reduced the neurological symptoms of ischemic stroke and ROS accumulation in the brain through IL-4/STAT6-dependent M2-type microglial polarization in MCAO mice. These results demonstrate that 2′-FL is a potentially effective therapeutic agent for ischemic stroke. [ABSTRACT FROM AUTHOR]

Brain ischemia is a common acute injury resulting from impaired blood flow to the brain. Translation of effective drug candidates from experimental models to patients has systematically failed. The use of human induced pluripotent stem cells (iPSC) offers new opportunities to gain translational insights into diseases including brain ischemia. We used a human 3D self-assembling iPSC-derived model (human cortical organoids, hCO) to characterize the effects of ischemia caused by oxygen-glucose deprivation (OGD). hCO exposed to 2 h or 8 h of OGD had neuronal death and impaired neuronal network complexity, measured in whole-mounting microtubule-associated protein 2 (MAP-2) immunostaining. Neuronal vulnerability was reflected by a reduction in MAP-2 mRNA levels, and increased release of neurofilament light chain (NfL) in culture media, proportional to OGD severity. Glial fibrillary acidic protein (GFAP) gene or protein levels did not change in hCO, but their release in medium increased after prolonged OGD. In conclusion, this human 3D iPSC-based in vitro model of brain ischemic injury is characterized by marked neuronal injury reflected by the release of the translational biomarker NfL which is relevant for testing neuroprotective strategies. [ABSTRACT FROM AUTHOR]

IntroductionThe life-sustaining treatment of hemodialysis (HD) induces recurrent and cumulative systemic circulatory stress resulting in cardiovascular injury. These recurrent insults compound preexisting cardiovascular sequalae leading to the development of myocardial injury and resulting in extremely high morbidity/mortality. This is largely a consequence of challenged microcirculatory flow within the myocardium (evidenced by detailed imaging-based studies). Currently, monitoring during HD is performed at the macrovascular level. Non-invasive monitoring of organ perfusion would allow the detection and therapeutic amelioration of this pathophysiological response to HD. Non-invasive percutaneous perfusion monitoring of the skin (using photoplethysmography—PPG) has been shown to be predictive of HD-induced myocardial stunning (a consequence of segmental ischemia). In this study, we extended these observations to include a dynamic assessment of skin perfusion during HD compared with directly measured myocardial perfusion during dialysis and cardiac contractile function.MethodsWe evaluated the intradialytic microcirculatory response in 12 patients receiving conventional HD treatments using continuous percutaneous perfusion monitoring throughout HD. Cardiac echocardiography was performed prior to the initiation of HD, and again at peak-HD stress, to assess the development of regional wall motion abnormalities (RWMAs). Myocardial perfusion imaging was obtained at the same timepoints (pre-HD and peak-HD stress), utilizing intravenous administered contrast and a computerized tomography (CT)-based method. Intradialytic changes in pulse strength (derived from PPG) were compared with the development of HD-induced RWMAs (indicative of myocardial stunning) and changes in myocardial perfusion.ResultsWe found an association between the lowest pulse strength reduction (PPG) and the development of RWMAs (p = 0.03) and also with changes in global myocardial perfusion (CT) (p = 0.05). Ultrafiltration rate (mL/kg/hour) was a significant driver of HD-induced circulatory stress [(associated with the greatest pulse strength reduction (p = 0.01), a reduction in global myocardial perfusion (p = 0.001), and the development of RWMAs (p = 0.03)].DiscussionPercutaneous perfusion monitoring using PPG is a useful method of assessing intradialytic hemodynamic stability and HD-induced circulatory stress. The information generated at the microcirculatory level of the skin is reflective of direct measures of myocardial perfusion and the development of HD-induced myocardial stunning. This approach for the detection and management of HD-induced cardiac injury warrants additional evaluation.

Ferroptosis is characterized by excessive accumulation of iron and lipid peroxides, which are involved in ischemia, reperfusion-induced organ injury, and stroke. Propofol, an anesthetic agent, has neuroprotective effects due to its potent antioxidant, anti-ischemic, and anti-inflammatory properties. However, the relationship between propofol and ferroptosis is still unclear. In the current study, we elucidated the role of ferroptosis in the neuroprotective effect of propofol in mouse brains subjected to cerebral ischemia reperfusion injury (CIRI). Ferroptosis was confirmed by Western blotting assays, transmission electron microscopy, and glutathione assays. Propofol regulated Nrf2/Gpx4 signaling, enhanced antioxidant potential, inhibited the accumulation of lipid peroxides in CIRI-affected neurons, and significantly reversed CIRI-induced ferroptosis. Additionally, Gpx4 inhibitor RSL3 and Nrf2 inhibitor ML385 attenuated the effects of propofol on antioxidant capacity, lipid peroxidation, and ferroptosis in CIRI-affected neurons. Our data support a protective role of propofol against ferroptosis as a cause of cell death in mice with CIRI. Propofol protected against CIRI-induced ferroptosis partly by regulating the Nrf2/Gpx4 signaling pathway. These findings may contribute to the development of future therapies targeting ferroptosis induced by CIRI. [ABSTRACT FROM AUTHOR]

Background: Cerebral ischemic stroke is the second major cause of mortality worldwide that results in persisting disability and mental agony. Ischemic stroke is induced by the diminished blood circulation to the brain, which can be due to obstruction by arteriosclerosis, fibromuscular dysplasia, or thrombosis. Triptonide is a diterpene triepoxide, purified out of extracts of Tripterygium wilfordii Hook F, and is an emerging target against, for example, cancers and inflammatory insults. Materials and Methods: Taking this into consideration, this study was designed to analyze the effect of triptonide on ischemic/reperfusion (I/R) cerebral infarction stroke rats. Results: Our study showed that triptonide decreased the infarct volume and brain edema produced by I/R. Moreover, triptonide protected the rats from any neurological deficits, which were analyzed using a five-point scoring system, augmented antioxidant enzymes like superoxide dismutase, catalase, glutathione peroxidase, reduced glutathione content, and lowered the activity of acetylcholinesterase. Triptonide also decreased the levels of pro-inflammatory cytokines such as interleukin-1 β (IL-1 β), TNF- α , and IL-6, while it augmented anti-inflammatory cytokines IL-10 and vascular endothelial growth factor. In this study, cerebral infarction stroke rats showed an increase in malondialdehyde levels. Triptonide preserved the normal brain architecture from various neurotoxic effects. Conclusion: Thus, triptonide can be targeted for drug discovery in the future to protect against cerebral infarction stroke. [ABSTRACT FROM AUTHOR]

Two electrocardiographic (ECG) aberrations encountered daily in ECG interpretation/overreading, which appear to be either unknown or ignored, by all caring for patients, are described herein: the 1st is the transient increase in the amplitude of QRS complexes in the right precordial ECG leads, leading to the erroneous diagnosis of left ventricular hypertrophy, often encountered in patients with episodes of supraventricular tachycardia, rapid sinus tachycardia, and atrial fibrillation; the 2nd is the spurious ST-segment elevations in lateral and/or inferior ECG leads in patients with right bundle branch block, interpreted by the automated ECG diagnostic algorithms as due to "acute myocardial infarction," "ischemic injury," "pericarditis," and "early repolarization," in the absence of such pathologies or electrophysiological explanations. [ABSTRACT FROM AUTHOR]

The study of transient receptor potential (TRP) channels has dramatically increased during the past few years. TRP channels function as sensors and effectors in the cellular adaptation to environmental changes. Here, we review literature investigating the physiological and pathophysiological roles of TRPC channels in the renal tubular system with a focus on TRPC3 and TRPC6. TRPC3 plays a key role in Ca2+ homeostasis and is involved in transcellular Ca2+ reabsorption in the proximal tubule and the collecting duct. TRPC3 also conveys the osmosensitivity of principal cells of the collecting duct and is implicated in vasopressin-induced membrane translocation of AQP-2. Autosomal dominant polycystic kidney disease (ADPKD) can often be attributed to mutations of the PKD2 gene. TRPC3 is supposed to have a detrimental role in ADPKD-like conditions. The tubule-specific physiological functions of TRPC6 have not yet been entirely elucidated. Its pathophysiological role in ischemia-reperfusion injuries is a subject of debate. However, TRPC6 seems to be involved in tumorigenesis of renal cell carcinoma. In summary, TRPC channels are relevant in multiples conditions of the renal tubular system. There is a need to further elucidate their pathophysiology to better understand certain renal disorders and ultimately create new therapeutic targets to improve patient care. [ABSTRACT FROM AUTHOR]

Abstract Background The exchange of mitochondria reportedly plays an important role in cell–cell communication in the central nervous system (CNS). The transfer of fragmented and dysfunctional astrocytic mitochondria into neurons and subsequent mitochondrial fusion often cause serious neuronal damage and cerebral ischaemic injury. Methods In this study, we prepared macrophage-derived exosomes laden with heptapeptide (Hep) as a dynamin-related protein-1 (Drp1)–fission 1 (Fis1) peptide inhibitor P110 to alleviate cerebral ischemia–reperfusion injury by reducing mitochondrial Drp1/Fis1 interaction-mediated astrocytic mitochondrial disorder and promoting the transfer of astrocyte-derived healthy mitochondria into neurons. Results The results demonstrated that Hep-loaded macrophage-derived exosomes (EXO-Hep) reduced mitochondrial damage in astrocytes by inhibiting the Drp1/Fis1 interaction after ischemia–reperfusion, ensuring the release of heathy astrocytic mitochondria and their subsequent transmission to neurons, alleviating mitochondria-mediated neuronal damage. Conclusion EXO-Hep significantly mitigated ischemic injury in a model of transient middle cerebral artery occlusion (tMCAO) by reducing the infarct area and improving neurological performance during the process of cerebral ischemia–reperfusion. Graphical Abstract

Background: Tourniquets provide better tissue visibility during arthroscopic surgery. However, multiple postoperative adverse events associated with ischemia may be caused by excessive inflation pressure and duration. We aimed to evaluate the degree of tourniquet-induced ischemia using a noninvasive continuous real-time monitoring method and the relationship between changes in tissue oxygen saturation (StO2) and blood biochemical markers of ischemic injuries in patients undergoing arthroscopic knee surgery. Methods: This was a prospective observational study using near-infrared spectroscopy (NIRS). Data were collected from 29 consecutive patients who underwent arthroscopic procedures. Twenty-five patients underwent anterior cruciate ligament reconstruction, and four underwent meniscal repair. We investigated tourniquet‐induced changes in StO2, monitored using NIRS, and blood biochemical markers of ischemic injuries. Results: A significant decrease in the mean StO2 from the baseline was observed during tourniquet inflation in the operative legs. The average decrease in the mean StO2 was 58%. A comparison of mean StO2 between the nonoperative and operative legs before tourniquet deflation showed that mean values of StO2 in the operative legs were significantly lower than those in the nonoperative legs. No significant clinical relationships were observed between changes in StO2 and blood biochemical markers of ischemic injuries (creatine kinase) (p = 0.04, r = 0.38) or tourniquet duration (p = 0.05, r = 0.366). Conclusions: Our results demonstrated that StO2 could be used to evaluate tissue perfusion in real time but did not support the hypothesis that StO2 is a useful method for predicting the degree of tourniquet-induced injury during arthroscopic knee surgery. [ABSTRACT FROM AUTHOR]

Myocardial ischemic injury and its resolution are the key determinants of morbidity or mortality in heart failure. The cause and duration of ischemia in patients vary. Numerous experimental models and methods have been developed to define genetic, metabolic, molecular, cellular, and pathophysiological mechanisms, in addition to defining structural and functional deterioration of cardiovascular performance. The rapid rise of big data, such as single-cell analysis techniques with bioinformatics, machine learning, and neural networking, brings a new level of sophistication to our understanding of myocardial ischemia. This mini-review explores the multifaceted nature of ischemic injury in the myocardium. We highlight recent state-of-the-art findings and strategies to show new directions of high-impact approach to understanding myocardial tissue remodeling. This next age of heart and circulatory physiology research will be more comprehensive and collaborative to uncover the origin, progression, and manifestation of heart failure while strengthening novel treatment strategies. [ABSTRACT FROM AUTHOR]

Pericytes are considered reparative mesenchymal stem cell-like cells, but their ability to ameliorate chronic ischemic kidney injury is unknown. We hypothesized that pericytes would exhibit renoprotective effects in murine renal artery stenosis (RAS). Porcine kidney-derived pericytes (5 x 105) or vehicle were injected into the carotid artery 2 wk after the induction of unilateral RAS in mice. The stenotic kidney glomerular filtration rate and tissue oxygenation were measured 2 wk later using magnetic resonance imaging. We subsequently compared kidney oxidative stress, inflammation, apoptosis, fibrosis, and systemic levels of oxidative and inflammatory cytokines. Treatment of xenogeneic pericytes ameliorated the RAS-induced loss of perfusion, glomerular filtration rate, and atrophy in stenotic kidneys and restored cortical and medullary oxygenation but did not blunt hypertension. Ex vivo, pericytes injection partially mitigated RAS-induced renal inflammation, fibrosis, oxidative stress, apoptosis, and senescence. Furthermore, coculture with pericytes in vitro protected pig kidney-1 tubular cells from injury. In conclusion, exogenous delivery of renal pericytes protects the poststenotic mouse kidney from ischemic injury, underscoring the therapeutic potential role of pericytes in subjects with ischemic kidney disease. [ABSTRACT FROM AUTHOR]

Efficient cell‐to‐cell communication is essential for tissue development, homeostasis, and the maintenance of cellular functions after injury. Tunneling nanotubes (TNTs) have emerged as a new important method of cell‐to‐cell communication. TNTs are primarily established between stressed and unstressed cells and can transport a variety of cellular components. Mitochondria are important trafficked entities through TNTs. Transcellular mitochondria transfer permits the incorporation of healthy mitochondria into the endogenous network of recipient cells, changing the bioenergetic profile and other functional properties of the recipient and may allow the recipient cells to recuperate from apoptotic processes and return to a normal operating state. Mesenchymal cells (MSCs) can form TNTs and transfer mitochondria and other constituents to target cells. This occurs under both physiological and pathological conditions, leading to changes in cellular energy metabolism and functions. This review summarizes the newly described capacity of melatonin to improve mitochondrial fusion/fission dynamics and promote TNT formation. This new evidence suggests that melatonin's protective effects could be attributed to its ability to prevent mitochondrial damage in injured cells, reduce senescence, and promote anastasis, a natural cell recovery phenomenon that rescues cells from the brink of death. The modulation of these new routes of intercellular communication by melatonin could play a key role in increasing the therapeutic potential of MSCs. [ABSTRACT FROM AUTHOR]

Cell therapy based on humanembryonic stem cells (hESCs) is a potential treatment for several human diseases caused by ischemic processes. Efficiency and feasibility of these therapies rely on understanding stem cell biology and the interaction and survival of these cells within the injured tissue. hESCs are an important source of diffusible bioactive paracrine modulators and the targets for different signaling molecules that prime cellular tissue repair. Notably, sphingosine 1‐phosphate (S1P) is an emerging bioactive lipid that activates G protein‐coupled receptors, known as S1P receptors (S1PR1–5), promoting cell survival, differentiation, and migration. It is shown that S1P increases cell viability and prevents death in about 50% after the ischemic insult. S1P‐mediated protectiveeffect is attributed to the modulation of S1PR3 and S1PR4 expression, which have been associated with the reperfusion injury salvage kinase/survivoractivating factor enhancement (RISK/SAFE) pathway. Involvement of the SAFE pathway is further verified by applying Janus Kinase (JAK2) and signal transducer and activation of transcription 3 pathway inhibitors, which prevents the S1P protective effect. An increase in sphingosine kinase (SphK) activity is also observed after S1P pretreatment. These results provide evidence for an S1P‐dependent, SphK positive feedback that stimulates hESCs to deliver large amounts of S1P. Thus, S1P protects hESC under ischemic conditions through the different receptors. Practical Applications: It is considered that S1P can be used as an adjuvant to pretreat hESCs prior to the administration in cell therapy‐based protocols for different diseases. [ABSTRACT FROM AUTHOR]

Mesenchymal stromal cells (MSC) are nonhematopoietic cells with fibroblast-like morphology and multipotent capacity that are widely used in pre-clinical and clinical investigations. Unfortunately, the efficiency of MSC treatment is hindered by the poor survival rate after transplantation at the damaged tissue. The goal of this study was to investigate the fate of MSC exposed to various stimuli mimicking the in vivo microenvironment post transplantation. To this aim, murine bone marrow–derived MSC were stimulated with IFNgama and TNFalpha under low oxygen (hypoxia) or atmospheric (normoxia) conditions for 24 to 72 hours, in order to better mimic an ischemic injury. The results showed that MSC pre-stimulation with TNFalpha and IFNgama enhanced immunosuppressive pathways by over-expression of NOS2, IDO, COX2 and production of NO. However, MSC viability was affected by these two cytokines in dose-dependent and time-dependent manners. Besides, priming with TNFalpha and/or IFNgama under low oxygen concentrations revealed that significantly increased cell mortality rate and decreased NO production. Our data suggest that both hypoxia and inflammation could impact the cell survival after transplantation and reinforces the necessity of further investigations to better understand MSC behavior after transplantation in order to identify the MSC-based strategies with the highest therapeutic potential.

Kanokwan Demeekul,1 Pratch Sukumolanan,2 Ratikorn Bootcha,3 Chattida Panprom,3 Soontaree Petchdee4 1Graduate School, Program of Bio-Veterinary Science, Kasetsart University, Kamphaeng Saen, Nakorn Pathom, Thailand; 2Veterinary Clinical Study Program, Faculty of Veterinary Medicine, Kasetsart University, Kamphaeng Saen, Nakorn Pathom, Thailand; 3Kasetsart University Veterinary Teaching Hospital, Faculty of Veterinary Medicine, Kamphaeng Saen, Nakorn Pathom, Thailand; 4Department of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, KamphaengSaen Campus, Kamphaeng Saen, ThailandCorrespondence: Soontaree PetchdeeDepartment of Large Animal and Wildlife Clinical Sciences, Faculty of Veterinary Medicine, Kasetsart University, KamphaengSaen Campus, Kamphaeng Saen, Nakorn Pathom, 73140, ThailandTel +66 34 351901-3Fax +66 34 351405Email fvetstr@ku.ac.thPurpose: The potential cardio-protective property of germinated brown rice (GBR) has been revealed by ameliorating risk factors related to cardiovascular diseases. This study hypothesized that the combination of GBR and cardioplegic solution could protect the cardiomyocytes exposed to simulated ischemic reperfusion injury in vitro study and preserve cardiac function during cardiopulmonary bypass surgery in animal models.Methods: Primary porcine cardiomyocytes were isolated and experimented cell viability against simulated ischemic reperfusion injury. In a cardiac surgical animal model, six pigs were randomly assigned to receive the two types of cardioplegic solution: i) St. Thomas cardioplegic solution (20 cc/kg); and ii) St. Thomas cardioplegic solution plus GBR (1 mg/kg). During open-heart surgery, the aorta was cross-clamped for 20 minutes, followed by reperfusion for 1 hour. Cardiopulmonary bypass parameters were recorded until the end of the procedure. Furthermore, hemodynamic parameters and arterial blood gas characteristics of animals among groups were monitored at different time points, including baseline before cardiopulmonary bypass (T1), during cardiopulmonary bypass (T2), during aortic clamp on (T3), and aortic clamp off (T4).Results: Primarily, GBR cotreatment with cardioplegic solution essentially resulted in the improvement of cell viability in primary porcine cardiomyocytes against simulated ischemic reperfusion induction. The findings from cardiac surgery demonstrated that mean arterial pressure and heart rate are constantly stable in cardioplegic solution combined with the GBR group, while the trend of potassium and lactase concentration was decreased in the animals receiving GBR group. Consistently, all parameters from arterial blood gas showed better outcomes in animals receiving GBR; however, there were no statistically significant differences between groups, except hepatic enzymes.Conclusion: Therefore, GBR might exert cardio-protective effects against ischemic reperfusion injury in the porcine cardiac surgery model due to anti-inflammatory response. These protective actions of GBR may explain the benefits gained from applying GBR products as a possible therapeutic supplement on cardiac diseases.Keywords: cardioprotection, cardiopulmonary bypass, germinated brown rice, ischemic injury, primary porcine cardiomyocytes

Abstract Background After ovarian tissue transplantation, ischemia-reperfusion injury and free radicals cause follicle depletion and apoptosis. Therefore, the use of antioxidants to reduce the production of free radicals is an important method to address the consequences of ischemia-reperfusion injury. Resveratrol is a natural active polyphenol compound with anti-inflammatory, antitumor, strong antioxidant and anti-free radical properties. The aim of this study was to investigate whether resveratrol could improve the effect of autologous ovarian transplantation after cryopreserve-thawn mouse ovarian tissue. Methods Whole-ovary vitrification and autotransplantation models were used to investigate the effects of resveratrol. Six-week-old female mice from the Institute of Cancer Research (ICR) were subjected to vitrification. All ovaries were preserved in liquid nitrogen for 1 week before being thawed. After thawing, ovarian tissues were autotransplanted in the bilateral kidney capsules. Mice (n = 72) were randomly divided into four groups to determine the optimal concentration of resveratrol (experiment I). Treatments were given as follows: saline, 5 mg/kg resveratrol, 15 mg/kg resveratrol and 45 mg/kg resveratrol, which were administered orally for one week. Grafted ovaries were collected for analysis on days 3, 7, and 21 after transplantation. Ovarian follicle morphology was assessed by hematoxylin and eosin staining. Serum FSH and E2 levels were measured to estimate the transplanted ovarian reserve and endocrine function. Other mice were randomly divided into two groups—saline and 45 mg/kg resveratrol to further evaluate the effect of resveratrol and explore the mechanisms underlying this effect (experiment II). Ovarian follicle apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays. Immunohistochemistry, qRT-PCR and western blotting (MDA, SOD, NF-κB, IL-6 and SIRT1) were used to explore the mechanisms of resveratrol. Moreover, oocytes derived from autotransplanted ovaries at 21 days were cultured and fertilized in vitro. Results The proportions of morphologically normal (G1) follicles at 3, 7 and 21 days were significantly higher in the 45 mg/kg resveratrol group than in the saline group. The TUNEL-stained follicles (%) at 7 days were significantly decreased in the 45 mg/kg resveratrol group compared with the saline group. Western blot analysis revealed that SOD2 and SIRT1 levels were significantly higher in the 45 mg/kg resveratrol group than in the saline group at day 7 and that MDA and NF-κB levels were lower in the saline group on day 3. Likewise, IL-6 was lower in the saline group on day 7. These results are basically consistent with the qRT-PCR results. In addition, the mean number of retrieved oocytes and fertilization and cleavage were significantly increased in the 45 mg/kg resveratrol group compared with the saline group. Conclusions Administration of resveratrol could improve the quality of cryopreserved mouse ovarian tissue after transplantation and the embryo outcome, through anti-inflammatory and antioxidative mechanisms.

Cerebral ischemic stroke is one of the leading causes of death and disability worldwide. 2′-fucosyllactose (2′-FL), a human milk oligosaccharide, exerts anti-inflammatory effects and plays a protective role in arterial thrombosis; however, its role in ischemic stroke remains unclear. This study aimed to investigate the neuroprotective effects of 2′-FL and its potential mechanisms in a mouse model of ischemic stroke. Neurological score and behavior tests revealed that 2′-FL promoted the recovery of neurological deficits and motor function in middle cerebral artery occlusion (MCAO) mice, and that 2′FL led to a reduction in the size of cerebral infarct. Biochemical studies showed that administration of 2′-FL led to a reduction of reactive oxygen species (ROS)-related products in the brain of MCAO mice. 2′-FL upregulated IL-10 and downregulated TNF-α level. In addition, 2′-FL enhanced M2-type microglial polarization and upregulated CD206 expression at 7 days after MCAO. At 3 days after MCAO, 2′-FL increased IL-4 levels and activated STAT6. Our data show that 2′-FL reduced the neurological symptoms of ischemic stroke and ROS accumulation in the brain through IL-4/STAT6-dependent M2-type microglial polarization in MCAO mice. These results demonstrate that 2′-FL is a potentially effective therapeutic agent for ischemic stroke.

Stroke is the most devastating disease, causing paralysis and eventually death. Many clinical and experimental trials have been done in search of a new safe and efficient medicine; nevertheless, scientists have yet to discover successful remedies that are also free of adverse effects. This is owing to the variability in intensity, localization, medication routes, and each patient's immune system reaction. HIF-1α represents the modern tool employed to treat stroke diseases due to its functions: downstream genes such as glucose metabolism, angiogenesis, erythropoiesis, and cell survival. Its role can be achieved via two downstream EPO and VEGF strongly related to apoptosis and antioxidant processes. Recently, scientists paid more attention to drugs dealing with the HIF-1 pathway. This review focuses on medicines used for ischemia treatment and their potential HIF-1α pathways. Furthermore, we discussed the interaction between HIF-1α and other biological pathways such as oxidative stress; however, a spotlight has been focused on certain potential signalling contributed to the HIF-1α pathway. HIF-1α is an essential regulator of oxygen balance within cells which affects and controls the expression of thousands of genes related to sustaining homeostasis as oxygen levels fluctuate. HIF-1α′s role in ischemic stroke strongly depends on the duration and severity of brain damage after onset. HIF-1α remains difficult to investigate, particularly in ischemic stroke, due to alterations in the acute and chronic phases of the disease, as well as discrepancies between the penumbra and ischemic core. This review emphasizes these contrasts and analyzes the future of this intriguing and demanding field. • HIF-1α plays an important role in the pathogenesis of cerebral ischemia. • VEGF-A increased in penumbra specifically in astrocytes and neurons. • HIF-1 reduces cellular ROS production by switching energy production. • Activation of HIF-1 leads to an increase in heme oxygenase-1 expression. • HIF-1α has a modulating effect on mitochondrial biogenesis and oxygen consumption. [ABSTRACT FROM AUTHOR]

Skull is a reservoir for supplying immune cells that mediate brain immune surveillance. However, during intravital optical imaging of brain, conventional cranial windows requiring skull thinning or removal disrupt brain immunity integrity. Here, a novel long‐term clearing cranial window (LCCW) based on the intact skull, dedicated to chronic skull transparency maintenance, is proposed. It significantly improves optical imaging resolution and depth, by which the cortical and calvarial vascular injury and regeneration processes after ischemic injury are longitudinally monitored in awake mice. Results show that calvarial blood vessels recover earlier than the cortex. And the transcriptome analysis reveals that gene expression patterns and immune cells abundances exist substantial differences between brain and skull after ischemic injury, which may be one of the causes for the time lag between their vascular recovery. These findings bring great enlightenment to vascular regeneration and reconstruction. Moreover, LCCW provides a minimally invasive approach for imaging the brain and skull bone marrow. [ABSTRACT FROM AUTHOR]

Background: The exchange of mitochondria reportedly plays an important role in cell–cell communication in the central nervous system (CNS). The transfer of fragmented and dysfunctional astrocytic mitochondria into neurons and subsequent mitochondrial fusion often cause serious neuronal damage and cerebral ischaemic injury. Methods: In this study, we prepared macrophage-derived exosomes laden with heptapeptide (Hep) as a dynamin-related protein-1 (Drp1)–fission 1 (Fis1) peptide inhibitor P110 to alleviate cerebral ischemia–reperfusion injury by reducing mitochondrial Drp1/Fis1 interaction-mediated astrocytic mitochondrial disorder and promoting the transfer of astrocyte-derived healthy mitochondria into neurons. Results: The results demonstrated that Hep-loaded macrophage-derived exosomes (EXO-Hep) reduced mitochondrial damage in astrocytes by inhibiting the Drp1/Fis1 interaction after ischemia–reperfusion, ensuring the release of heathy astrocytic mitochondria and their subsequent transmission to neurons, alleviating mitochondria-mediated neuronal damage. Conclusion: EXO-Hep significantly mitigated ischemic injury in a model of transient middle cerebral artery occlusion (tMCAO) by reducing the infarct area and improving neurological performance during the process of cerebral ischemia–reperfusion. [ABSTRACT FROM AUTHOR]

Periventricular leukomalacia (PVL) and cerebral palsy are two neurological disease conditions developed from the premyelinated white matter ischemic injury (WMI). The significant pathophysiology of these diseases is accompanied by the cognitive deficits due to the loss of function of glial cells and axons. White matter makes up 50% of the brain volume consisting of myelinated and non-myelinated axons, glia, blood vessels, optic nerves, and corpus callosum. Studies over the years have delineated the susceptibility of white matter towards ischemic injury especially during pregnancy (prenatal, perinatal) or immediately after child birth (postnatal). Impairment in membrane depolarization of neurons and glial cells by ischemia-invoked excitotoxicity is mediated through the overactivation of NMDA receptors or non-NMDA receptors by excessive glutamate influx, calcium, or ROS overload and has been some of the well-studied molecular mechanisms conducive to the injury of white matter. Expression of glutamate receptors (GluR) and transporters (GLT1, EACC1, and GST) has significant influence in glial and axonal-mediated injury of premyelinated white matter during PVL and cerebral palsy. Predominantly, the central premyelinated axons express extensive levels of functional NMDA GluR receptors to confer ischemic injury to premyelinated white matter which in turn invoke defects in neural plasticity. Several underlying molecular mechanisms are yet to be unraveled to delineate the complete pathophysiology of these prenatal neurological diseases for developing the novel therapeutic modalities to mitigate pathophysiology and premature mortality of newborn babies. In this review, we have substantially discussed the above multiple pathophysiological aspects of white matter injury along with glial dynamics, and the pharmacotherapies including recent insights into the application of MSCs as therapeutic modality in treating white matter injury. [ABSTRACT FROM AUTHOR]

Abstract Skull is a reservoir for supplying immune cells that mediate brain immune surveillance. However, during intravital optical imaging of brain, conventional cranial windows requiring skull thinning or removal disrupt brain immunity integrity. Here, a novel long‐term clearing cranial window (LCCW) based on the intact skull, dedicated to chronic skull transparency maintenance, is proposed. It significantly improves optical imaging resolution and depth, by which the cortical and calvarial vascular injury and regeneration processes after ischemic injury are longitudinally monitored in awake mice. Results show that calvarial blood vessels recover earlier than the cortex. And the transcriptome analysis reveals that gene expression patterns and immune cells abundances exist substantial differences between brain and skull after ischemic injury, which may be one of the causes for the time lag between their vascular recovery. These findings bring great enlightenment to vascular regeneration and reconstruction. Moreover, LCCW provides a minimally invasive approach for imaging the brain and skull bone marrow.

Sepsis-associated encephalopathy (SAE) is a diffuse central nervous system (CNS) dysfunction during sepsis, and is associated with increased mortality and poor outcomes in septic patients. Despite the high incidence and clinical relevance, the exact mechanisms driving SAE pathogenesis are not yet fully understood, and no specific therapeutic strategies are available. Regulatory T cells (Tregs) have a role in SAE pathogenesis, thought to be related with alleviation of sepsis-induced hyper-inflammation and immune responses, promotion of T helper (Th) 2 cells functional shift, neuroinflammation resolution, improvement of the blood-brain barrier (BBB) function, among others. Moreover, in a clinical point of view, these cells have the potential value of improving neurological and psychiatric/mental symptoms in SAE patients. This review aims to provide a general overview of SAE from its initial clinical presentation to long-term cognitive impairment and summarizes the main features of its pathogenesis. Additionally, a detailed overview on the main mechanisms by which Tregs may impact SAE pathogenesis is given. Finally, and considering that Tregs may be a novel target for immunomodulatory intervention in SAE, different therapeutic options, aiming to boost peripheral and brain infiltration of Tregs, are discussed. [ABSTRACT FROM AUTHOR]

Abstract In this study, we evaluated the combined therapeutic efficacy of erythropoietin (a hematopoietic hormone produced by the fetal liver and kidney in response to inflammation and apoptosis) and sesame oil (from Sesamum indicum L.) on ischemic kidney injury following kidney transplantation in a rat model. Rats were assigned to the following groups: sham, control, 1000 U/kg erythropoietin, 1 mL/kg sesame oil, 1000 U/kg erythropoietin + 1 mL/kg sesame oil, and positive control. We measured the levels of blood urea nitrogen (BUN), creatinine, alanine aminotransferase (ALT), lipid peroxidation, reactive oxygen species (ROS), reduced glutathione (GSH), antioxidant enzymes, and proinflammatory markers and performed renal histopathological evaluation. The combined erythropoietin and sesame oil treatment significantly reduced BUN, ALT, creatinine, lipid peroxidation, ROS, and proinflammatory markers and GSH and antioxidant enzyme levels. Histopathological examination showed that the combined erythropoietin and sesame oil treatment significantly reduced necrosis. Therefore, combined treatment of sesame oil and erythropoietin may represent an effective therapeutic approach against ischemic kidney injury after kidney transplantation.

Sepsis-associated encephalopathy (SAE) is a diffuse central nervous system (CNS) dysfunction during sepsis, and is associated with increased mortality and poor outcomes in septic patients. Despite the high incidence and clinical relevance, the exact mechanisms driving SAE pathogenesis are not yet fully understood, and no specific therapeutic strategies are available. Regulatory T cells (Tregs) have a role in SAE pathogenesis, thought to be related with alleviation of sepsis-induced hyper-inflammation and immune responses, promotion of T helper (Th) 2 cells functional shift, neuroinflammation resolution, improvement of the blood-brain barrier (BBB) function, among others. Moreover, in a clinical point of view, these cells have the potential value of improving neurological and psychiatric/mental symptoms in SAE patients. This review aims to provide a general overview of SAE from its initial clinical presentation to long-term cognitive impairment and summarizes the main features of its pathogenesis. Additionally, a detailed overview on the main mechanisms by which Tregs may impact SAE pathogenesis is given. Finally, and considering that Tregs may be a novel target for immunomodulatory intervention in SAE, different therapeutic options, aiming to boost peripheral and brain infiltration of Tregs, are discussed.

Background: Clinically, ischemic reperfusion injury is the main cause of stroke injury. This study aimed to assess the effectiveness of fingolimod in suppressing inflammation caused by ischemic brain injury and explore its pharmacological mechanisms., Methods: In total, 75 male Sprague-Dawley rats were randomly and equally assigned to five distinct groups: sham, middle cerebral artery occlusion/reperfusion (MCAO/R) surgery, fingolimod low-dose (F-L), fingolimod medium-dose (F-M), and fingolimod high-dose (F-H). Neurobehavioral tests, 2,3,5-triphenyltetrazolium chloride staining, and the brain tissue drying-wet method were conducted to evaluate neurological impairment, cerebral infarction size, and brain water content. Enzyme-linked immunosorbent assay was employed to quantify pro-inflammatory cytokines interleukin (IL)-1β, IL-6, and tumor necrosis factor-alpha (TNF-α) protein levels. Western blotting and immunohistochemical staining were performed to assess high mobility group box 1 (HMGB1), toll-like receptor 4 (TLR4), and nuclear factor kappa-B p65 (NF-κBp65) levels., Results: Rats in the F-L, F-M, and F-H groups exhibited lower Longa scores, reduced infarction volumes, and decreased brain edema than those in the MCAO/R group. Additionally, the F-L, F-M, and F-H groups exhibited lower serum levels of IL-1β, IL-6, and TNF-α than those of the MCAO/R group. Additionally, F-L, F-M, and F-H treatments resulted in decreased HMGB1, TLR4, and NF-κBp65 protein expression levels in the hippocampus of MCAO/R rats., Conclusions: Fingolimod was found to reduce ischemic brain injury in a dose-dependent manner. Moreover, it was also found to alleviate inflammation following ischemic brain injury via the HMGB1/TLR4/NF‑κB signaling pathway., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Published by IMR Press.)

The aim of this study is to do a study of cryoinjury and ischaemic injury on testicular graft during cryopreservation and transplantation. According to time at 1, 3, 7 and 14 days after transplantation, the grafts were collected for immunohistochemistry assay for CD34 (blood vessel marker), VEGF (neoangiogenesis marker), caspase‐3 (apoptosis marker) MAGE‐A4 (germ cell marker). A significant increase was observed in the density of VEGF‐positive blood vessels on day 3, reached a peak on day 7. On post‐transplant day 3, a sharp increase occurred in the rate of spermatogonia‐expressing caspase‐3 until the day 7. At 14th day after transplantation, the spermatogonia number per round tubule of nonfrozen grafts was 41 ± 5.9% from that of fresh control tissues, while, in frozen‐thawed grafts, the spermatogonia number per round tubule was 36.8 ± 4.6% from that of fresh control tissues. In testicular grafts, angiogenesis initiated reperfusion from day 3, and the formation of new blood vessel generally is completed about 7 days after transplantation. Angiogenesis in grafts after transplantation plays a crucial role in the restoration of function. Therefore, minimising ischaemic injury as well as improvement of cryopreservation protocols are needed to improve testicular graft after freezing, thawing and grafting. [ABSTRACT FROM AUTHOR]

Inflammation is an important event in ischemic injury. These immune responses begin with the expression of pro-inflammatory genes modulating transcription factors, such as nuclear factor-κB (NF-κB), activator protein-1 (AP-1), and signal transducers and activator of transcription-1 (STAT-1). The 70-kDa heat shock protein (Hsp70) can both induce and arrest inflammatory reactions and lead to improved neurological outcome in experimental brain injury and ischemia. Since Hsp70 are induced under heat stress, we investigated the link between Hsp70 neuroprotection and phosphorylation of inhibitor of κB (IκB), c-Jun N-terminal kinases (JNK) and p38 through co-immunoprecipitation and enzyme-linked immunosorbent assay (ELISA) assay. Transcription factors and pro-inflammatory genes were quantified by immunoblotting, electrophoretic-mobility shift assay and reverse transcription-polymerase chain reaction assays. The results showed that heat stress led to Hsp70 overexpression which rendered neuroprotection after ischemia-like injury. Overexpression Hsp70 also interrupts the phosphorylation of IκB, JNK and p38 and blunts DNA binding of their transcription factors (NF-κB, AP-1 and STAT-1), effectively downregulating the expression of pro-inflammatory genes in heat-pretreated astrocytes. Taken together, these results suggest that overexpression of Hsp70 may protect against brain ischemia via an anti-inflammatory mechanism by interrupting the phosphorylation of upstream of transcription factors.

Heart failure in adults is a leading cause of morbidity and mortality worldwide. It can arise from a variety of diseases, with most resulting in a loss of cardiomyocytes that cannot be replaced due to their inability to replicate, as well as to a lack of resident cardiomyocyte progenitor cells in the adult heart. Identifying and exploiting mechanisms underlying loss of developmental cardiomyocyte replicative capacity has proved to be useful in developing therapeutics to effect adult cardiac regeneration. Of course, effective regeneration of myocardium after injury requires not just expansion of cardiomyocytes, but also neovascularization to allow appropriate perfusion and resolution of injury-induced inflammation and interstitial fibrosis, but also reversal of adverse left ventricular remodeling. In addition to overcoming these challenges, a regenerative therapy needs to be safe and easily translatable. Failure to address these critical issues will delay the translation of regenerative approaches. This review critically analyzes current regenerative approaches while also providing a framework for future experimental studies aimed at enhancing success in regenerating the injured heart.