Ischemia/Reperfusion Injury Revisited: An Overview of the Latest Pharmacological Strategies

Regulatory effects of resveratrol on nitric oxide signaling in cardiovascular diseases

Cardiovascular illnesses are multifactorial disorders and represent the primary reasons for death worldwide, according to the World Health Organization. As a signaling molecule, nitric oxide (NO) is extremely permeable across cellular membranes owing to its unique molecular features, like its small molecular size, lipophilicity, and free radical properties. Some of the biological effects of NO are vasodilation, inhibition in the growth of vascular smooth muscle cells, and functional regulation of cardiac cells. Several therapeutic approaches have been tested to increase the production of NO or some downstream NO signaling pathways. The health benefits of red wine are typically attributed to the polyphenolic phytoalexin, resveratrol (3,5,4'-trihydroxy-trans-stilbene), which is found in several plant species. Resveratrol has beneficial cardiovascular properties, some of which are mediated through endothelial nitric oxide synthase production (eNOS). Resveratrol promotes NO generation from eNOS through various methods, including upregulation of eNOS expression, activation in the enzymatic activity of eNOS, and reversal of eNOS uncoupling. Additionally, by reducing of oxidative stress, resveratrol inhibits the formation of superoxide and inactivation NO, increasing NO bioavailability. This review discusses the scientific literature on resveratrol's beneficial impact on NO signaling and how this effect improves the function of vascular endothelium.

Heliox alleviates ischemia-reperfusion-induced damage to neuronal cells by repressing the USP46-SNX5 Axis-triggered ferroptosis

BACKGROUND

Cerebral ischemia-reperfusion (I/R) causes brain cell dysfunction and death. Heliox treatment shows therapeutic benefits in treating certain respiratory conditions. Here, we explore the mechanism by which heliox alleviates ferroptosis of neuronal cells injured by I/R treatment.

METHOD

OGD/R-treated SH-SY5Y cells were used and screened for USPs whose expression is induced by OGD/R but suppressed by heliox treatment. Mass spectrometry was conducted to identify proteins that interact with USP46. The impact of SNX5 deficiency on the ferroptosis of USP46-overexpressing neuronal cells following sequential OGD/R and heliox treatment was also explored. Finally, the effect of USP46 overexpression on brain cell ferroptosis in a cerebral I/R rat model was explored.

RESULTS

Deubiquitinase USP46 is targeted by heliox treatment in neuronal cells. USP46 expression is stimulated by I/R, and its overexpression enhances ferroptosis in I/R-treated neuronal cells. USP46 interacts with and deubiquitinates SNX5, a ferroptosis promoter, thereby increasing its stability. The knockdown of SNX5 abolishes the ferroptosis-promoting effect of USP46 in I/R-treated neuronal cells. Excessive USP46 attenuates the protective effect of heliox treatment on I/R-triggered cerebral damage in a rat model.

CONCLUSION

These observations highlight the ferroptosis-promoting function of the USP46-SNX5 axis in I/R-treated neuronal cells.

Liver ischemia reperfusion injury: Mechanisms, cellular pathways, and therapeutic approaches

Liver ischemia-reperfusion injury (LIRI) is a critical challenge in liver transplantation, resection, and trauma surgeries, leading to significant hepatic damage due to oxidative stress, inflammation, and mitochondrial dysfunction. This review explores the cellular and molecular mechanisms underlying LIRI, focusing on ATP depletion, mitochondrial dysfunction, and the involvement of reactive oxygen species (ROS). Inflammatory pathways, including the activation of nuclear factor-kappa B (NF-κB) and the NLRP3 inflammasome, as well as pro-inflammatory cytokines such as TNF-α and IL-1β, play a crucial role in exacerbating tissue damage. Various types of cell death, including necrosis, apoptosis, necroptosis, pyroptosis, ferroptosis and cuproptosis are also discussed. Therapeutic interventions targeting these mechanisms, such as antioxidants, anti-inflammatories, mitochondrial protectors, and signaling modulators, have shown promise in pre-clinical studies. However, translating these findings into clinical practice faces challenges due to the limitations of animal models and the complexity of human responses. Emerging therapies, such as RNA-based treatments, genetic editing, and stem cell therapies, offer potential breakthroughs in LIRI management. This review highlights the need for further research and the development of innovative therapeutic approaches to improve clinical outcomes.

Cytosolic nucleic acid sensing as driver of critical illness: mechanisms and advances in therapy

Nucleic acids from both self- and non-self-sources act as vital danger signals that trigger immune responses. Critical illnesses such as acute respiratory distress syndrome, sepsis, trauma and ischemia lead to the aberrant cytosolic accumulation and massive release of nucleic acids that are detected by antiviral innate immune receptors in the endosome or cytosol. Activation of receptors for deoxyribonucleic acids and ribonucleic acids triggers inflammation, a major contributor to morbidity and mortality in critically ill patients. In the past decade, there has been growing recognition of the therapeutic potential of targeting nucleic acid sensing in critical care. This review summarizes current knowledge of nucleic acid sensing in acute respiratory distress syndrome, sepsis, trauma and ischemia. Given the extensive research on nucleic acid sensing in common pathological conditions like cancer, autoimmune disorders, metabolic disorders and aging, we provide a comprehensive summary of nucleic acid sensing beyond critical illness to offer insights that may inform its role in critical conditions. Additionally, we discuss potential therapeutic strategies that specifically target nucleic acid sensing. By examining nucleic acid sources, sensor activation and function, as well as the impact of regulating these pathways across various acute diseases, we highlight the driving role of nucleic acid sensing in critical illness.

Tephrosia purpurea, with (-)-Pseudosemiglabrin as the Major Constituent, Alleviates Severe Acute Pancreatitis-Mediated Acute Lung Injury by Modulating HMGB1 and IL-22

Ischemia-reperfusion (IR) injury is a major cause of multiple organ failure. The purpose of this study was to look into the role of Tephrosia purpurea (TEP) and its active constituent pseudosemiglabrin (PS) in alleviating severe acute pancreatitis and its associated acute lung injury. We established a rat pancreatic IR model, and the rats were treated with TEP (200 mg/kg and 400 mg/kg) and PS (20 and 40 mg/kg), in addition to the IR control and sham groups. The results showed that the respiratory parameters, including inspiratory time (Ti), expiratory time (Te), duration (Dr), and respiratory rate (RR), were comparable among all groups, while peak inspiratory flow (PIF), forced vital capacity (FVC), and forced expiratory volume at 0.1 s (FEV0.1) were significantly impaired. Notably, PS at 40 mg/kg showed normal PIF, FVC, and FEV0.1/FVC compared to the IR group, indicating an improved lung function. Additionally, TEP and PS showed protective effects on pancreatic and lung tissues compared to the IR control group, with the following effects: alleviating pathological damage; reducing serum levels of trypsinogen activation peptide (TAP), lipase, and amylase; decreasing oxidative stress markers such as MDA and MPO; restoring antioxidant enzyme activity (GPx); suppressing inflammatory markers TNF-α, IL-6, and NF-κB; downregulating HMGB1 gene in pancreatic tissue; and upregulating the IL-22 gene in lung tissues. In conclusion, the obtained findings demonstrate that oral supplementation of TEP and PS to rats with pancreatic IR alleviates pancreatic and lung injuries by reducing oxidative stress and modulating inflammatory processes, which offers an attractive therapeutic option for severe acute pancreatitis and its associated acute lung injury.

Sunitinib's Effect on Bilateral Optic Nerve Damage in Rats Following the Unilateral Clamping and Unclamping of the Common Carotid Artery

Background/objectives: Common carotid artery occlusion can cause oxidant and inflammatory damage to the optic nerve. In this study, the effect of sunitinib was investigated, the antioxidant and anti-inflammatory properties of which have been previously reported and shown to be protective in I/R injury and in preventing bilateral optic nerve ischemia-reperfusion (I/R) injuries after unilateral common carotid artery ligation in rats. Methods: In this study, 18 Albino Wistar male rats were divided into SG (sham-operated), CCU (clamping and unclamping), and SCCU (sunitinib + clamping and unclamping) groups. One hour before the surgical procedures, sunitinib (25 mg/kg, oral) was given to SCCU rats. Anesthesia was induced with ketamine (60 mg/kg, ip) and sevoflurane. The right common carotid arteries of all rats were accessed under anesthesia. While the skin opened in SG rats was closed with sutures, the right common carotid arteries of CCU and SCCU rats were clipped, and an ischemia period was created for 10 min. Then, reperfusion (6 h) was achieved by unclipping. After euthanasia with ketamine (120 mg/kg, intraperitoneally), the right and left optic nerves of the rats were removed and examined biochemically and histopathologically. Results: Malondialdehyde, tumor necrosis factor α, interleukin-1β, and interleukin-6 were increased, and total glutathione levels had decreased in both ipsilateral and contralateral optic nerves (p < 0.05). These changes were more prominent on the ipsilateral side. Similarly, histopathological damage was observed to be more on the ipsilateral side (p < 0.05). Biochemical and histopathological changes were significantly suppressed in rats receiving sunitinib treatment (p < 0.05). Conclusions: Sunitinib may protect optic nerve tissue against I/R injury by reducing oxidative stress and inflammation.

Synthetic Bilirubin-Based Nanomedicine Protects Against Renal Ischemia/Reperfusion Injury Through Antioxidant and Immune-Modulating Activity

Renal ischemia/reperfusion injury (IRI) is a common form of acute kidney injury. The basic mechanism underlying renal IRI is acute inflammation, where oxidative stress plays an important role. Although bilirubin exhibits potent reactive oxygen species (ROS)-scavenging properties, its clinical application is hindered by problems associated with solubility, stability, and toxicity. In this study, BX-001N, a synthetic polyethylene glycol-conjugated bilirubin 3α nanoparticle is developed and assessed its renoprotective effects in renal IRI. Intravenous administration of BX-001N led to increase uptake in the kidneys with minimal migration to the brain after IRI. Peri-IRI BX-001N administration improves renal function and attenuates renal tissue injury and tubular apoptosis to a greater extent than free bilirubin on day 1 after IRI. BX-001N suppressed renal infiltration of inflammatory cells and reduced expression of TNF-α and MCP-1. Furthermore, BX-001N increases renal tubular regeneration on day 3 and suppresses renal fibrosis on day 28. BX-001N decreases the renal expressions of dihydroethidium, malondialdehyde, and nitrotyrosine after IRI. In conclusion, BX-001N, the first Good Manufacturing Practice-grade synthetic bilirubin-based nanomedicine attenuates acute renal injury and chronic fibrosis by suppressing ROS generation and inflammation after IRI. It shows adequate safety profiles and holds promise as a new therapy for renal IRI.

Klotho plays a crucial role in the renal-protective effect of allopurinol on renal ischemia-reperfusion injury

BACKGROUND

Allopurinol, a xanthine oxidase inhibitor, recovers histological alterations and renal dysfunction induced during renal ischemic-reperfusion injury. This study investigated the cross-talk between the allopurinol and soluble Klotho.

METHODS

Rats were randomly divided into three equal groups (n = 8 per group): The sham-operated group without renal ischemia, the BIR (bilateral ischemia-reperfusion) group which underwent renal ischemia, and BIR+Allo (allopurinol) group which was pretreated with allopurinol (100 mg/kg- gavage) 30 min before the renal ischemia. After recovery from the anesthesia, all animals were placed in metabolic cages to collect their urine after 24 h, plasma was extracted from blood samples taken from the tail vein-plasma and urine samples were saved at -20 °C. Kidneys were harvested and weighed. The left kidney was dropped in the buffer of 10 % formalin for H&E staining, and the right kidney was located in liquid nitrogen and saved at -80 °C for the oxidative stress analysis.

RESULTS

After renal ischemia-reperfusion, serum creatinine, blood urea nitrogen, xanthine oxidase, and total oxidative stress levels significantly increased. However, plasma Klotho level and total antioxidative capacity decreased in the BIR group. There was a reverse correlation between Klotho and xanthine oxidase levels. The pre-treatment with allopurinol increased plasma Klotho, induced a protective effect on renal histopathological changes, and corrected functional biomarkers.

CONCLUSION

Our results showed that allopurinol enhanced the antioxidative effects by increasing Klotho activity. Therefore, Klotho may be involved in the protective effects of allopurinol on the renal injury induced by BIR.

Synthesis and evaluation of enzyme inhibition by novel TT01001 derivatives as monoamine oxidase B inhibitors

Monoamine oxidase (MAO) B is a promising target for treating stroke reperfusion injury, Parkinson's disease as well as other neurodegenerative diseases. Pharmacological inhibitors of this enzyme have demonstrated the ability to modulate critical neurotransmitter levels, decrease damaging reactive oxygen species and neuroinflammation, and improve mitochondrial dysfunction. We identified TT01001 from a pilot screen which showed good potency for inhibiting MAO-B, with a half-maximal inhibitory concentration below 10 μM. In this study, we explored quantitative-structure activity relationships (QSAR) of 60 derivatives of TT01001 evaluated for MAO-B. Approximately half of these 60 compounds showed IC50 values superior to that of TT01001 (10). Two of the compounds, 37 and 57, displayed improved MAO-B potency and selectivity from MAO-A, with IC50 values of 270 and 460 nM respectively. The mode of inhibition of was determined to be both competitive and reversible, and both compounds exhibited moderate ability to passively diffuse across biological membranes. These compounds can be offered as-is for subsequent drug development processes, or they can be derivatized further using the structure-activity relationship information found herein.

Forsythiaside A Ameliorates Oxidative Damage Caused by Cerebral Ischemia Through the Nrf2/HO-1 Signaling Pathway

Forsythiaside A (FA) has anti-inflammatory and antioxidant properties. The aim of this study was to explore the antioxidant effects and mechanisms of FA in ischemic stroke (IS). In this work, IS-related genes were obtained through GEO, GeneCards, TTD, CTD, DrugBank, and MalaCards databases. The targets of the FA were obtained from CTD, TargetNet, Super-PRED, TCMIO, and SwissTargetPrediction databases. GO analysis and KEGG pathway enrichment analysis were performed, and a protein-protein interaction (PPI) network was constructed to screen for key pathways. For in vivo assays, a middle cerebral artery occlusion and reperfusion (MCAO/R) model was established in rats, and high and low doses of FA were administered. Neurological impairment score, cerebral infarction, cerebral edema, and tissue morphology were evaluated. The content of reactive oxygen species (ROS), malondialdehyde (MDA) and superoxide dismutase (SOD) were detected. The expressions of cleaved caspase 3, Bax, and bcl-2, and Nrf2/HO-1 pathway-related proteins were detected by Western blot. For in vitro experiments, an oxygen-glucose deprivation/reperfusion (OGD/R) model was constructed in HT22 cells, and CCK-8 and LDH release assays were used to evaluate the effect of FA on OGD/R-induced toxicity of HT22 neurons. The Nrf2 inhibitor ML385 was used for the rescue experiments. Network pharmacology and bioinformatics analysis showed that the role of FA in treating IS was associated with oxidative stress. Topological analysis of the PPI network revealed 11 key genes, which were closely associated with the Nrf2 pathway. FA treatment could significantly reduce cerebral infarction, cerebral edema, neurological function impairment, and neuronal injury of the rats with MCAO/R. FA could also inhibit oxidative stress and neuronal apoptosis, and increase the viability of HT22 cells. In addition, FA promoted the nuclear translocation of Nrf2 and activated the Nrf2/HO-1 pathway, while ML385 weakened the protective effect of FA on neuronal viability and antioxidant capacity. In conclusion, FA attenuates the oxidative damage induced by IS by activating the Nrf2/HO-1 signaling pathway, which is a promising natural drug for IS.

Unlocking the Potential of l-α-Glycerylphosphorylcholine: From Metabolic Pathways to Therapeutic Applications

l-α-Glycerylphosphorylcholine (GPC), also known as choline alphoscerate or α-glycerophosphorylcholine, serves as both a pharmaceutical product and a dietary supplement. Through its metabolic pathways, GPC acts as the precursor not only of choline and acetylcholine but also of various phospholipids. Extensive preclinical and clinical evidence demonstrates that GPC effectively alleviates cognitive impairment associated with Alzheimer's disease, vascular dementia, cerebral ischemia, stress, and epilepsy, among other conditions. Additionally, GPC has beneficial effects on such conditions and measures as ischemic/hypoxic conditions, ionizing radiation-induced damage, exercise performance, growth hormone release, and liver damage. As well as facilitating cholinergic neurotransmission, evidence also indicates GPC, among other activities, also can promote γ-aminobutyric acid release, enhance protein kinase C activity, facilitate hippocampal neurogenesis, upregulate neurotrophic factors, and inhibit inflammation. In preclinical studies, results indicate that GPC is not genotoxic in vitro or in vivo. Extensive human studies indicate GPC causes no severe adverse effects. Possible risks of atherosclerosis and stroke await necessary validation. In this review, the GPC-related metabolic pathways, pharmacological effects, mechanisms of action, and safety evaluation are discussed with the aim of providing a comprehensive understanding of GPC.

Taohong Siwu Decoction Combined With the LncRNA H19/miR-675-5p Axis Repairs Limb Ischemia-Reperfusion Injury Through the Regulation of the Wnt3a/Ca2+ Signaling Pathway

Background: Taohong Siwu decoction (THSWT) has shown therapeutic effects on ischemia/reperfusion injury (IRI). This study tended to investigate the role of THSWT combined with the long non-coding RNA (LncRNA) H19 (H19)/miR-675-5p axis in improving limb IRI (LIRI). Methods: Hind LIRI rats and simulated IRI skeletal myoblasts models were constructed to evaluate the therapeutic effects of THSWT. The mechanism of THSWT treatment on LIRI was investigated by the regulation of the H19/miR-675-5p axis and the wingless/integrated (Wnt)/Ca2+ signaling pathway. Various assessments, such as H&E staining, TUNEL staining, flow cytometry, cell counting kit-8 (CCK-8) assay, quantitative real-time polymerase chain reaction (qRT-PCR), western blot, immunohistochemistry (IHC) staining, enzyme-linked immunosorbent assay (ELISA), biochemical assay, and calcium fluorescence imaging, were conducted to observe skeletal muscle injury, cell apoptosis, skeletal myoblast proliferation, gene and protein expressions, cytokine levels, glucose (Glu) uptake, and Ca2+ concentration. Results: THSWT intervention effectively improved skeletal muscle injury in LIRI rats, as evidenced by reduced muscle fiber damage and decreased cell apoptosis, accompanied by downregulation of H19, miR-675-5p, cleaved-Caspase3, Bax, PLC, and PKC expressions and upregulation of Bcl2 expression. Furthermore, silencing of H19 inhibited cell apoptosis of skeletal muscle and reduced IL-1β, IL-6, and TNF-α levels in LIRI rats. Notably, THSWT intervention combined with the silencing of H19 synergistically promoted the repair of skeletal muscle injury in LIRI rats. Mechanistically, THSWT intervention combined with regulation of the H19/miR-675-5p axis promoted the proliferation of skeletal myoblasts damaged by IRI through the Wnt3a/Ca2+ signaling pathway, increasing the levels of intracellular Bcl2, while decreasing the levels of Ca2+, CaMKⅡ, PLC, PKC, cleaved-Caspase3, Bax, TNF-α, IL-1β, IL-6, Wnt3a, and β-catenin. Conclusions: THSWT combined with the regulation of the H19/miR-675-5p axis effectively improved LIRI by modulating the Wnt3a/Ca2+ signaling pathway, providing insights for potential therapeutic strategies for LIRI.

Comprehensive analysis of immunogenic cell death-related genes in liver ischemia-reperfusion injury

Background

Liver ischemia-reperfusion injury (LIRI) is a critical condition after liver transplantation. Understanding the role of immunogenic cell death (ICD) may provide insights into its diagnosis and potential therapeutic targets.

Methods

Differentially expressed genes (DEGs) between LIRI and normal samples were identified, and pathway enrichment analyses were performed, followed by immune infiltration assessment through the CIBERSORT method. The consensus clustering analysis was conducted to separate LIRI clusters and single-sample Gene Set Enrichment Analysis (ssGSEA) was used to analyze the distinct immune states between clusters. Weighted Gene Co-Expression Network Analysis (WGCNA) was employed to identify hub genes associated with ICD. To establish diagnostic models, four machine learning techniques, including Random Forest (RF), XGBoost (XGB), Support Vector Machine (SVM), and Generalized Linear Models (GLM), were applied to filter gene sets. The receiver operating characteristic (ROC) curves were utilized to assess the performance of the models.

Results

Pathway enrichment results revealed significant involvement of cytokines and chemokines among DEGs of LIRI. Immune infiltration analysis indicated higher levels of specific immune functions in Cluster 2 compared to Cluster 1. WGCNA identified significant modules linked to LIRI with strong correlations between module membership and gene significance. The RF and SVM machine learning algorithms were finally chosen to construct the models. Both demonstrated high predictive accuracy for diagnosing LIRI not only in training cohort GSE151648 but also in validation cohorts GSE23649 and GSE15480.

Conclusions

The study highlights the pivotal roles of ICD-related genes in LIRI, providing diagnosis models with potential clinical applications for early detection and intervention strategies against LIRI.

Prevention of ischemia-reperfusion injury on the porcine model of supra-renal aortic clamp by sulodexide

BACKGROUND

The ischemia-reperfusion injury (IRI) is unavoidable in vascular surgery. Damage to the microcirculation and endothelial glycocalyx might set up a shock with loss of circulatory coherence and organ failure. Sulodexide may help to protect endothelial glycocalyx and alleviate the ischemia-reperfusion injury.

METHODS

Twenty female piglets underwent surgery with a 30-min-long suprarenal aortic clamp, followed by two hours of reperfusion. Ten piglets received sulodexide before the clamp, and 10 received normal saline. Blood and urine samples were taken at baseline and in 20-min intervals until the 120th minute to analyze the serum syndecan-1, E-selectin, and thrombomodulin. Albumin and glycosaminoglycans were examined in the urine. The kidney biopsies before and after the protocol were examined by light microscopy with hematoxylin-eosin staining. The sublingual microcirculation was recorded by side-stream dark field imaging at the time as blood and urine.

RESULTS

Based on the 2-way ANOVA testing, there was no statistically significant difference in the parameters of sublingual microcirculation. Serum markers of endothelial cell activation and damage (E-selectin and thrombomodulin) did not show any statistically significant difference either. Syndecan-1, a marker of glycocalyx damage, showed statistically significantly higher values based on the 2-way ANOVA testing (p < 0.0001) with the highest difference in the 80th minute: 7.8 (3.9-44) ng/mL in the control group and 1.8 (0.67-2.8) ng/mL in the sulodexide group. In the urine, the albuminuria was higher in the control group, although not statistically significant. Glycosaminoglycans were statistically significantly higher in the sulodexide group based on the mixed-effect analysis due to the intervention itself. Histological analysis of the renal biopsies showed necrosis in both groups after reperfusion.

CONCLUSION

Administering sulodexide significantly reduced the level of endothelial markers of IRI. The study results support further research into using preemptive administration of sulodexide to modulate IRI in clinical medicine.

Protective Effects of BPC 157 on Liver, Kidney, and Lung Distant Organ Damage in Rats with Experimental Lower-Extremity Ischemia-Reperfusion Injury

Background and Objectives: Ischemia-reperfusion (I/R) injury can affect multiple distant organs following I/R in the lower extremities. BPC-157's anti-inflammatory and free radical-neutralizing properties suggest its potential in mitigating ischemia-reperfusion damage. This study evaluates the protective effects of BPC-157 on remote organ damage, including the kidneys, liver, and lungs, in a rat model of skeletal muscle I/R injury. Materials and Methods: A total of 24 male Wistar albino rats were randomly divided into four groups: sham (S), BPC-157(B), lower extremity I/R(IR) and lower extremity I/R+BPC-157(I/RB). Some 45 min of ischemia of lower extremity was followed by 2 h of reperfusion of limbs. BPC-157 was applied to groups B and I/RB at the beginning of the procedure. After 2 h of reperfusion, liver, kidney and lung tissues were harvested for biochemical and histopathological analyses. Results: In the histopathological examination, vascular and glomerular vacuolization, tubular dilation, hyaline casts, and tubular cell shedding in renal tissue were significantly lower in the I/RB group compared to other groups. Lung tissue showed reduced interstitial edema, alveolar congestion, and total damage scores in the I/RB group. Similarly, in liver tissue, sinusoidal dilation, necrotic cells, and mononuclear cell infiltration were significantly lower in the I/RB group. Additionally, the evaluation of TAS, TOS, OSI, and PON-1 revealed a statistically significant increase in antioxidant activity in the liver, lung, and kidney tissues of the I/RB group. Conclusions: The findings of this study demonstrate that BPC-157 exerts a significant protective effect against distant organ damage in the liver, kidneys, and lungs following lower extremity ischemia-reperfusion injury in rats.

Protective Role of Oxycodone in Myocardial Oxidative Stress and Mitochondrial Dysfunction Induced by Ischemia-Reperfusion

Ischemia-reperfusion (I/R) injury is a significant clinical problem impacting the heart and other organs, such as the kidneys and liver. This study explores the protective effects of oxycodone on myocardial I/R injury and its underlying mechanisms. Using a myocardial I/R model in Sprague-Dawley (SD) rats and an oxygen-glucose deprivation/reoxygenation (OGD/R) model in H9c2 cells, we administered oxycodone and inhibited AMP-activated protein kinase (AMPK) with Compound C (C.C). Our results showed that oxycodone significantly reduced lactate dehydrogenase (LDH) release and reactive oxygen species (ROS) production while stabilizing mitochondrial membrane potential (MMP). Western blot and RT-qPCR analyzes confirmed that oxycodone enhances AMPK phosphorylation and upregulates the expression of Silent Information Regulator 1 (SIRT1) and Peroxisome Proliferator-Activated Receptor γ Coactivator 1α (PGC-1α), thereby protecting myocardial cells. These findings suggest that oxycodone exerts significant protective effects against I/R injury by activating the AMPK pathway, offering new potential therapeutic targets for myocardial protection.

Proteomic Screening of Early Reperfusion in Acute Ischemic Heart and Insights into Mitochondrial-Associated Cell Damage: Role of RIP3

BACKGROUND

Regulated forms of necrosis-like cell death (e.g., necroptosis) have been shown to contribute to cardiac ischemia/reperfusion (I/R) injury. However, pro-inflammatory necroptosis is unlikely to be involved during early reperfusion and little is known about the associated molecular changes. Thus, this study aimed to provide an in-depth protein screening with a particular focus on pro-pyroptotic and mitochondrial damage-related pathways.

METHODS

Langendorff-perfused rat hearts were subjected to 30-minute global ischemia followed by 10-minute reperfusion. Liquid chromatography coupled with mass spectrometry (LC-MS/MS) and immunoblotting techniques were used to study the complex cardiac proteome. In addition, calcium-induced mitochondrial swelling and lactate dehydrogenase (LDH) release were examined to assess mitochondrial stress and necrosis phenotype, respectively.

RESULTS

Approximately 160 proteins linked to cell death signaling, cellular metabolism, and post-translational modifications were significantly differentially expressed in I/R hearts compared to controls. Conventional proteins of pyroptosis, either of canonical or non-canonical signaling, were not affected during the short reperfusion. Notably, this type of I/R was associated with increased expression of p25 cleaved form of poly [ADP-ribose] polymerase 1 (PARP1 p25) and mature apoptosis-inducing factor (AIF), alongside nitrosative stress and mitochondrial swelling. Conversely, a receptor-interacting protein kinase 3 (RIP3) inhibitor (GSK'872, 250 nM) reversed mitochondrial swelling and plasma membrane rupture and mitigated the increase in the expression of PARP1 p25 and AIF.

CONCLUSIONS

This study shows for the first time that necrosis-like injury during early I/R of the isolated heart is associated with mitochondrial events, rather than pro-inflammatory pyroptotic cell death. Furthermore, the inhibition of RIP3 mitigates this injury independent of targeting pro-inflammatory signaling.

Protective effects of neutrophil serine protease inhibition against ischemia-reperfusion injury in lung or heart transplantation

Transplanted organs are inevitably exposed to ischemia-reperfusion (IR) injury, which is known to cause graft dysfunction. Functional and structural changes that follow IR tissue injury are mediated by neutrophils through the production of oxygen-derived free radicals, as well as from degranulation which entails the release of proteases and other pro-inflammatory mediators. Neutrophil serine proteases (NSPs) are believed to be the principal triggers of post-ischemic reperfusion damage. Extended preservation times for the transplanted donor organ correlate with heightened occurrences of vascular damage and graft dysfunction. Preservation with α1-antitrypsin, an endogenous inhibitor of NSPs, improves primary graft function after lung or heart transplantation. Furthermore, pre-operative pharmacological targeting of NSP activation in the recipient using chemical inhibitors suppresses neutrophilic inflammation in transplanted organs. Hence, effective control of NSPs in the graft and recipient is a promising strategy to prevent IR injury. In this review, we describe the pathological functions of NSPs in IR injury and discuss their pharmacological inhibition to prevent primary graft dysfunction in lung or heart transplantation.

Inhibition of p70 Ribosomal S6K1 Protects the Myocardium against Ischemia/Reperfusion-Induced Necrosis through Downregulation of RIP3

BACKGROUND

Myocardial ischemia-reperfusion (I/R) injury refers to cell damage that occurs as a consequence of the restoration of blood circulation following reperfusion therapy for cardiovascular diseases, and it is a primary cause of myocardial infarction. The search for nove therapeutic targets in the context of I/R injury is currently a highly active area of research. p70 ribosomal S6 kinase (S6K1) plays an important role in I/R induced necrosis, although the specific mechanisms remain unclear.

OBJECTIVE

This study aims to explore the effects of inhibiting S6K1 on myocardial I/R injury and its potential mechanisms.

METHODS

A rat myocardial I/R model was created and treated with the S6K1-specific inhibitor PF-4708671. Hematoxylin-eosin (H&E) staining was applied to evaluate the pathological changes in cardiac tissues. 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to measure the area of myocardial infarction (MI). Left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), the maximum rate of increase in left ventricular pressure (+dp/dtmax), and the maximum rate of the decrease in left ventricular pressure (-dp/dtmax) were measured using ultrasonic echocardiography. The expression levels of cardiac troponin-1 (cTn-1), lactate dehydrogenase (LDH), creatine kinase MB (CK-MB), and aspartate aminotransferase (AST) were determined by enzyme-linked immunosorbent assay (ELISA). Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining and propidium iodide (PI) staining were used to examine the apoptosis and necrosis of myocardial tissues. The expressions of apoptotic-related proteins, and key molecules of necrosis were detected by western blot. The relationship between S6K1 and receptor-interacting protein kinase 3 (RIP3) was analyzed by immunoprecipitation.

RESULTS

Inhibition of S6K1 reduces I/R-induced myocardial tissue damage, improves myocardial function, and inhibits myocardial tissue necrosis (p < 0.05). In addition, RIP3 is a direct target of S6K1, and activation of RIP3 blocked the protective effect of the S6K1 inhibitor PF-4708671 against myocardial I/R injury (p < 0.05).

CONCLUSION

Inhibition of S6K1 protects against myocardial I/R injury by down-regulating RIP3, suggesting that targeting S6K1 may offer a novel approach for intervention in myocardial I/R injury.

The temporal relationship between mitochondrial quality and renal tissue recovery following ischemia-reperfusion injury

Background

Growing evidence indicates that disruptions in mitochondrial quality management contribute to the development of acute kidney injury (AKI), incomplete or maladaptive kidney repair, and chronic kidney disease. However, the temporal dynamics of mitochondrial quality control alterations in relation to renal injury and its recovery remain poorly understood and are addressed in this manuscript.

Method

ology: Male Wistar rats (n = 60) were subjected to varying durations of ischemia and reperfusion. Ischemia was instigated by clamping both renal arteries and for reperfusion, the clamps were removed to restore the blood flow. Renal injury, physiological function, mitochondrial assessment, and cellular mediators were analyzed.

Results

Prolonging ischemia duration reduces bioenergetic function while disrupting the balance of mitochondrial fusion, fission, and mitophagy at the gene expression level while maintaining intact mitochondrial copy number. However, reperfusing a kidney after 45 min of ischemia with varying reperfusion times exacerbates mitochondrial dysfunction and significantly decreases mitochondrial copy number. These declines are particularly evident at 24 h of reperfusion, with some parameters improving by 7 days of reperfusion. Despite these improvements, 7 days of reperfusion did not correlate with renal injury indicators (CrCl- 0.46 ± 0.01, BUN-86.29 ± 4.9, Cr-1.75 ± 0.16) following 45 min of ischemia. Conversely, 15 min of ischemia followed by 7 days of reperfusion restored mitochondrial quality and renal function (CrCl- 7.33 ± 0.59, BUN-43.6 ± 3.16, Cr-0.93 ± 0.14).

Conclusion

The above findings emphasize that mitochondrial quality control alters with the extent of ischemia and subsequent reperfusion time, impacting not only mitochondrial copy number but also the resilience of mitochondria during tissue repair.

Exploring Potential Complement Modulation Strategies for Ischemia-Reperfusion Injury in Kidney Transplantation

The complement system plays a crucial role in regulating the inflammatory responses in kidney transplantation, potentially contributing to early decline in kidney function. Ischemia-reperfusion injury (IRI) is among the factors affecting graft outcomes and a primary contributor to delayed graft function. Complement activation, particularly the alternative pathway, participates in the pathogenesis of IRI, involving all kidney compartments. In particular, tubular epithelial cells often acquire a dysfunctional phenotype that can exacerbate complement activation and kidney damage. Currently, complement-modulating drugs are under investigation for the treatment of kidney diseases. Many of these drugs have shown potential therapeutic benefits, but no effective clinical treatments for renal IRI have been identified yet. In this review, we will explore drugs that target complement factors, complement receptors, and regulatory proteins, aiming to highlight their potential value in improving the management of renal IRI.

Late Postpartum Eclampsia with Posterior Reversible Encephalopathy Syndrome and Subarachnoid Hemorrhage: A Case Study

Eclampsia is a multisystem disorder of pregnancy and the puerperium. Posterior reversible encephalopathy syndrome (PRES), a neurotoxic condition characterized by various neurological symptoms, can arise from multiple causes including eclampsia. Although hemorrhage is a possible complication of PRES, subarachnoid hemorrhage (SAH) is a rare occurrence in eclamptic patients with this condition. A 33-year-old female patient presented with acute severe headache and blurred vision two days after delivery. This progressively worsened over the next five days before she was admitted to the hospital. A magnetic resonance imaging (MRI) brain scan with contrast revealed a picture suggestive of PRES. Following admission, she had seizures, and a follow-up MRI revealed an acute subarachnoid hemorrhage. Treatment started, and the patient improved and was discharged from the hospital without any residual symptoms. This case illustrates how eclampsia can be a risk factor for PRES, and although hemorrhagic PRES is becoming more recognized, SAH remains an unusual but critical presentation. Early and accurate diagnosis, along with effective management, is crucial for achieving a positive outcome.

A proof-of-concept study in small and large animal models for coupling liver normothermic machine perfusion with mesenchymal stromal cell bioreactors

To fully harness mesenchymal-stromal-cells (MSCs)' benefits during Normothermic Machine Perfusion (NMP), we developed an advanced NMP platform coupled with a MSC-bioreactor and investigated its bio-molecular effects and clinical feasibility using rat and porcine models. The study involved three work packages: 1) Development (n = 5): MSC-bioreactors were subjected to 4 h-liverless perfusion; 2) Rat model (n = 10): livers were perfused for 4 h on the MSC-bioreactor-circuit or with the standard platform; 3) Porcine model (n = 6): livers were perfused using a clinical device integrated with a MSC-bioreactor or in its standard setup. MSCs showed intact stem-core properties after liverless-NMP. Liver NMP induced specific, liver-tailored, changes in MSCs' secretome. Rat livers exposed to bioreactor-based perfusion produced more bile, released less damage and pro-inflammatory biomarkers, and showed improved mithocondrial function than those subjected to standard NMP. MSC-bioreactor integration into a clinical device resulted in no machine failure and perfusion-related injury. This proof-of-concept study presents a novel MSC-based liver NMP platform that could reduce the deleterious effects of ischemia/reperfusion before transplantation.

Endothelial Dysfunction and Cardiovascular Disease: Hyperbaric Oxygen Therapy as an Emerging Therapeutic Modality?

Maintaining the physiological function of the vascular endothelium and endothelial glycocalyx is crucial for the prevention of cardiovascular disease, which is one of the leading causes of morbidity and mortality worldwide. Damage to these structures can lead to atherosclerosis, hypertension, and other cardiovascular problems, especially in individuals with risk factors such as diabetes and obesity. Endothelial dysfunction is associated with ischemic disease and has a negative impact on overall cardiovascular health. The aim of this review was to comprehensively summarize the crucial role of the vascular endothelium and glycocalyx in cardiovascular health and associated thrombo-inflammatory conditions. It highlights how endothelial dysfunction, influenced by factors such as diabetes, chronic kidney disease, and obesity, leads to adverse cardiovascular outcomes, including heart failure. Recent evidence suggests that hyperbaric oxygen therapy (HBOT) may offer therapeutic benefits in the treatment of cardiovascular risk factors and disease. This review presents the current evidence on the mechanisms by which HBOT promotes angiogenesis, shows antimicrobial and immunomodulatory effects, enhances antioxidant defenses, and stimulates stem cell activity. The latest findings on important topics will be presented, including the effects of HBOT on endothelial dysfunction, cardiac function, atherosclerosis, plaque stability, and endothelial integrity. In addition, the role of HBOT in alleviating cardiovascular risk factors such as hypertension, aging, obesity, and glucose metabolism regulation is discussed, along with its impact on inflammation in cardiovascular disease and its potential benefit in ischemia-reperfusion injury. While HBOT demonstrates significant therapeutic potential, the review also addresses potential risks associated with excessive oxidative stress and oxygen toxicity. By combining information on the molecular mechanisms of HBOT and its effects on the maintenance of vascular homeostasis, this review provides valuable insights into the development of innovative therapeutic strategies aimed at protecting and restoring endothelial function to prevent and treat cardiovascular diseases.

Bioprospecting hydroxylated chalcones in in vitro model of ischemia-reoxygenation and probing NOX4 interactions via molecular docking

Ischemia/reperfusion injury (I/R) is a leading cause of acute kidney injury (AKI) in conditions like kidney transplants, cardiac surgeries, and nephrectomy, contributing to high global mortality and morbidity. This study aimed to analyze the protective effects of 2'-hydroxychalcones in treating I/R-induced AKI by targeting key pathological pathways. Considering strong antioxidant action along with other pharmacological roles of chalcone derivatives, six 2'-hydroxychalcones were synthesized via Claisen-Schmidt condensation and analyzed for their protective effects in an I/R induced AKI model using HK-2 cells. Among six 2'-hydroxychalcones, chalcone A4 significantly increased the HK-2 cells viability compared to I/R group. Chalcone A4 reduced the cell death events by reducing generation of cytoplasmic ROS and mitochondrial transmembrane potential. It also increased GSH and SOD activity while reducing TBARS levels, indicating strong antioxidant action. Scanning electron microscope images showed that chalcone A4 reversed I/R-induced morphological changes in HK-2 cells, including apoptotic blebbing and cytoplasmic fragmentation. Furthermore, in silico studies revealed interactions with NADPH oxidase 4, further supporting its protective role in I/R-induced AKI. These results showed that chalcone A4 possess potential protective action against I/R induced cellular damage possibly due to its strong antioxidant action and potential interaction with NOX4 subunit of NADPH oxidase.

99mTc(I)-Labeled His-Tagged Proteins: Impact in the Development of Novel Imaging Probes and in Drug Discovery

Technetium-99 m (99mTc) remains the cornerstone of nuclear medicine for single photon emission computed tomography (SPECT) due to its widespread availability and chemical and physical features. Its multiple oxidation states allow for the design and production of radiopharmaceuticals with versatile properties, namely in terms of pharmacokinetic profile. 99mTc(V) is the most common oxidation state, but 99mTc(I) gained traction after the pioneering work of Alberto and colleagues, which resulted in the introduction of the organometallic core fac-[99mTc(CO)3(H2O)3]+. This core is readily available from [99mTcO4]- and displays three labile water molecules that can be easily swapped for ligands with different denticity and/or donor atoms in aqueous environment. This makes it possible to radiolabel small molecules as well as high molecular weight molecules, such as antibodies or other proteins, while assuring biological activity. Direct radiolabelling of those proteins with fac-[99mTc(CO)3]+ under mild conditions is accomplished through incorporation of a polyhistidine tag (His-tag), a commonly used tag for purification of recombinant proteins. This review aims to address the direct radiolabelling of His-tagged macromolecules with fac-[99mTc(CO)3]+ for development of molecular imaging agents and the impact of this technology in the discovery and development of imaging and/or therapeutic agents towards clinical application.

Liraglutide alleviates ferroptosis in renal ischemia reperfusion injury via inhibiting macrophage extracellular trap formation

BACKGROUND AND PURPOSE

Renal transplantation and other conditions with transiently reduced blood flow is major cause of renal ischemia/reperfusion injury (RIRI), a therapeutic challenge clinically. This study investigated the role of liraglutide in ferroptosis-associated RIRI via macrophage extracellular traps (METs).

METHODS

Animal model with RIRI was established in C57BL/6J mice. A total of 72 C57BL/6J mice were used with 8 mice per group. Primary tubular epithelium was co-culture with RAW264.7 under hypoxia/reoxygenation (H/R) condition to mimic in vitro. Liraglutide was administrated into mice and cells. Extracellular DNA, neutrophil elastase and myeloperoxidase in serum and supernatant of cell medium were collected for measuring METs. F4/80 and citH3 were labeled to show METs.

RESULTS

Liraglutide relieved RIRI and ferroptosis in vivo, and inhibited renal I/R-induced METs both in vivo and in vitro. F4/80 and citrullinated histone H3 (citH3) were highly co-localized after RIRI. Liraglutide attenuated the co-localization of citH3 and F4/80. Expressions of M2 markers were enhanced whereas these of M1 markers suppressed during liraglutide treatment in RIRI. Phosphorylation of signal transducer and activator of transcription (STAT)1, 3 and 6 were increased in RIRI mice and H/R-induced RAW264.7. However, liraglutide decreased phosphorylation of STAT1 and increased phosphorylation of STAT3 and STAT6. STAT3/6 inhibition reversed liraglutide-inhibited M1 polarization, extracellular traps and ferroptosis.

CONCLUSION

Liraglutide inhibited ferroptosis-induced renal dysfunction since it skewed macrophage polarization into M2 phenotype that interfered the formation of extracellular traps based on STAT3/6 pathway during RIRI. Liraglutide was proposed to be used for RIRI clinical treatment.

Mesenchymal stem cell-derived exosomal microRNA-367-3p mitigates lower limb ischemia/reperfusion injury in mouse skeletal muscle via EZH2 targeting

OBJECTIVE

This study aimed to investigate the protective effect of bone marrow mesenchymal stem cell-derived exosomes (BMSCs-exo) against lower limb ischemia/reperfusion (I/R) injury-induced pyroptosis in skeletal muscle.

METHODS

A mouse model of lower limb I/R injury was utilized to assess the impact of BMSCs-exo, particularly when loaded with microRNA-367-3p (miR-367-3p), on pyroptosis. Histological examination, wet weight/dry weight ratio measurements, and luciferase assays were employed to elucidate the mechanisms involved.

KEY FINDINGS

BMSCs-exo effectively suppressed pyroptosis in injured skeletal muscle tissue. Loading BMSCs-exo with miR-367-3p enhanced this protective effect by downregulating key pyroptosis-related proteins. Luciferase assays identified enhancer of zeste homolog 2 (EZH2) as a direct target of miR-367-3p in BMSCs-exo.

CONCLUSIONS

BMSCs-exo loaded with miR-367-3p safeguarded mouse skeletal muscle against pyroptosis-induced I/R injury by targeting EZH2. These findings offer valuable insights into potential therapeutic strategies for lower limb I/R injuries, emphasizing the therapeutic potential of BMSCs-exo in mitigating tissue damage caused by pyroptosis.

Dexmedetomidine alleviates CoCl2-induced hypoxic cellular damage in INS-1 cells by regulating autophagy

BACKGROUND

Ischemia-reperfusion (I/R) injury is inevitable during the perioperative period. The pancreas is susceptible to I/R injury. Autophagy, a self-digestion process, is upregulated during I/R injury and strongly induced by hypoxia. This study aims to determine whether dexmedetomidine can decrease pancreatic β-cell damage by regulating autophagy under hypoxia.

METHODS

INS-1 rat insulinoma cells were cultured in dexmedetomidine before being exposed to cobalt chloride (CoCl2)-induced hypoxia. Cell viability and the expression of autophagy-related proteins (light chain 3B [LC3B]-II, p62, and ATGs) were assessed. The expression of apoptosis-related proteins (BCL-2 and P-BAD) were also evaluated. CoCl2-treated INS-1 cells were pretreated with the autophagosome formation inhibitor, 3-methyladenine (3-MA), to compare its effects with those of dexmedetomidine. Bafilomycin-A1 (Baf-A1) that inhibits autophagosome degradation was used to confirm the changes in autophagosome formation induced by dexmedetomidine.

RESULTS

Dexmedetomidine attenuated the increased expression of autophagic proteins (LC3B-II, p62, and ATGs) and reversed the CoCl2-induced reduction in the proliferation of INS-1 cells after hypoxia. Dexmedetomidine also alleviated the decreased expression of the anti-apoptotic protein (BCL-2) and the increased expression of apoptotic protein (BAX). Dexmedetomidine reduces the activation of autophagy through inhibiting autophagosome formation, as confirmed by a decrease in LC3B-II/I ratio, a marker of autophagosome formation, in LC3B turnover assay combined with Baf-A1.

CONCLUSIONS

Dexmedetomidine alleviates the degree of cellular damage in INS-1 cells against CoCl2-induced hypoxia by regulating autophagosome formation. These results provide a basis for further studies to confirm these effects in clinical practice.

Paricalcitol prevents renal tubular injury induced by ischemia-reperfusion: Role of oxidative stress, inflammation and AT1R

The vitamin D receptor (VDR) is associated with antioxidative and anti-inflammatory effects and modulation of the renin-angiotensin-aldosterone system. This study evaluated whether VDR agonist paricalcitol protects renal ischemia-reperfusion (IR) induced tubular injury in rats by evaluating: 1) ATP-dependent tubular Na+ transport; 2) renal redox signaling; 3) renal content of proinflammatory cytokines TNF-α and IL-6; and 4) renal content of renin and angiotensin II receptor type 1 (AT1R). Paricalcitol prevented IR-induced tubular injury, evidenced by the prevention of histopathological changes and renal fibrosis with preservation of the activity of ATP-dependent Na+ transporters in the renal cortex. Paricalcitol decreased renal oxidative stress by reducing NADPH oxidase activity and increasing catalase. Paricalcitol also decreased the renal content of TNF-α, IL-6, and AT1R. The NADPH oxidase inhibitor apocynin did not present additive protection to paricalcitol-induced effects. The protective effects of paricalcitol on tubular injury induced by renal IR may dependent on the modulation of redox and proinflammatory signaling and renal angiotensin II/AT1R signaling.

Dose-related effects of ciproxifan on brain tissue in rats with cerebral ischemia-reperfusion

PURPOSE

Cerebral ischemia is the result of decreased or interrupted blood flow to the brain. It is the third leading cause of death after cardiovascular disease and cancer. Cerebral ischemia is reversible or irreversible in neurons in the affected area, and subsequent free radical damage can be exacerbated if reperfusion occurs. Ciproxifan is used to study the involvement of histaminergic neurons in different phases such as wakefulness and cognition. We wanted to find out whether ciproxifan has a protective effect on the brain of rats with cerebral ischemia-reperfusion injury.

MATERIALS AND METHODS

A total of 64 adult rats (32 male and 32 female) were used for the experiment. Eight cages were formed with randomly selected rats. No substance was administered to the rats in Group 1 and no surgical procedure was performed. The cerebral ischemia-reperfusion model (clamping of the left common carotid artery for 15 min followed by reperfusion for 24 h) was applied to rats in Group 2, Group 3, and Group 4 after 7 days/single dose of saline and ciproxifan (10 mg/kg, 30 mg/kg). After that, the activitymeter, forced swim test (FST), and Morris water maze (MWM) were performed on all animals.

RESULTS

Rats treated with ciproxifan exhibit neurons and glial cells with histologic structures similar to those of the control group, and interestingly, these differences became more pronounced with increasing dose. Rats administered ciproxifan improved motor coordination, decreased total distance behavior, and improved learning ability. However, when the groups were compared by sex, no significant difference was found in the parameters.

CONCLUSION

Thus, we could conclude that ciproxifan has a protective effect on the brain to a certain extent, regardless of the dose.

The Use of Autologous Omentum Transposition as a Therapeutic Intervention to Reduce the Complication of Ischemia/Reperfusion Injuries in a Rat Model

Background

Ischemia/reperfusion injury (IRI) causes cellular dysfunction and death in organs like the kidney, heart, and brain. It involves energy depletion during ischemia and oxidative stress, inflammation, and apoptosis during reperfusion. Kidney IRI often leads to acute kidney injury (AKI) in various clinical scenarios. The omentum, an adipose tissue with healing properties, has been used to treat injuries in different organs.

Objective

This study aimed to assess the omentum's healing effects on reducing IRI's adverse effects after renal ischemia in Wistar rats.

Method

A total number of 36 male Wistar rats were used in a study on IRI-induced AKI. Rats were divided into 6 groups of normal kidneys wrapped with omentum "Sham-1" and "Sham-2," ischemic kidney wrapped with omentum as "OMT-1" and "OMT-2," and ischemic kidney without omentum as "Control-1" and "Control-2." Ischemia was induced by clamping the left renal artery for 45 minutes. The omentum was transposed onto the injured kidney in "OMT" group. After sacrifice at weeks 4 and 8, kidney histology and blood samples were analyzed for kidney function markers.

Results

On the first day after surgery, there was an immediate increase in creatinine and blood urea nitrogen (BUN) levels, which then decreased by day 28. Both OMT groups showed significantly lower levels of creatinine and BUN compared to Control groups on day 1, but after 28 days differences were not statistically significant. Histological analysis using H&E and Masson's trichrome staining revealed significantly higher levels of inflammatory cell infiltration and hyperemia in the OMT groups. However, fibrosis and glomerular shrinkage were higher in the Control groups.

Conclusion

Using an omental flap significantly prevented fibrosis within the renal parenchyma, slow down the AKI progression, and potentially serving as a promising therapeutic strategy for kidney dysfunction.

Endothelial RIPK3 minimizes organotypic inflammation and vascular permeability in ischemia-reperfusion injury

Recent studies have revealed a link between endothelial receptor-interacting protein kinase 3 (RIPK3) and vascular integrity. During mouse embryonic development, hypoxia can trigger elevated endothelial RIPK3 that contributes to lethal vascular rupture. However, it is unknown whether RIPK3 regulate endothelial barrier function in adult vasculature under hypoxic injury conditions such as ischemia-reperfusion (I/R) injury. Here we performed inducible genetic deletion of endothelial Ripk3 ( Ripk iECKO ) in mice, which led to elevated vascular permeability in the small intestine and multiple distal organs after intestinal I/R injury. Mechanistically, this vascular permeability correlated with increased endothelial secretion of IL-6 and organ-specific expression of VCAM-1 and ICAM-1 adhesion molecules. Circulating monocyte depletion with clodronate liposomes reduced permeability in organs with elevated adhesion molecules, highlighting the contribution of monocyte adhesion and extravasation to Ripk iECKO barrier dysfunction. These results elucidate mechanisms by which RIPK3 regulates endothelial inflammation to minimize vascular permeability in I/R injury.

GRAPHICAL ABSTRACT

Transient cerebral ischaemia alters mesenteric arteries in hypertensive rats: Limited reversal despite suberoylanilide hydroxamic acid cerebroprotection

Stroke induces brain injury, especially severe in hypertensive patients, and elevates mortality rates through non-neurological complications. However, the potential effects of a transient ischaemic episode on the peripheral vasculature of hypertensive individuals remain unclear. We investigated whether transient cerebral ischaemia (90 min)/reperfusion (1 or 8 days) induces alterations in mesenteric resistance artery (MRA) properties in adult male spontaneously hypertensive rats (SHR). In addition, we assessed whether the reported cerebroprotective effects of suberoylanilide hydroxamic acid (SAHA; 50 mg/kg; administered intraperitoneally at 1, 4, or 6 h after reperfusion onset) extend over several days and include beneficial effects on MRAs. Functional and structural properties of MRAs were examined at 1- and 8-days post-stroke. Nuclei distribution, collagen content, and oxidative stress were assessed. Ischaemic brain damage was evaluated longitudinally using magnetic resonance imaging. Following stroke, MRAs from SHR exhibited non-reversible impaired contractile responses to the thromboxane A2 receptor agonist U46619. Stroke increased the MRA cross-sectional area, wall thickness, and wall/lm ratio due to augmented collagen deposition. These changes were partially sustained 8 days later. SAHA did not improve U46619-induced contractions but mitigated stroke-induced oxidative stress and collagen deposition, preventing MRA remodelling at 24 h of reperfusion. Furthermore, SAHA induced sustained cerebroprotective effects over 8 days, including reduced brain infarct and oedema, and improved neurological scores. However, SAHA had minimal impact on chronic MRA contractile impairments and remodelling. These findings suggest that stroke causes MRA changes in hypertensive subjects. While SAHA treatment offers sustained protection against brain damage, it cannot fully restore MRA alterations.

Tanshinone IIA Protects Ischemia/Reperfusion-Induced Cardiomyocyte Injury by Inhibiting the HAS2/FGF9 Axis

Purpose

This study aimed to investigate the impacts of tanshinone IIA (Tan IIA) on ischemia/reperfusion (I/R)-induced cardiomyocyte injury in coronary heart disease (CHD), and to determine whether Tan IIA regulates myocardial cell injury induced by I/R through the Hyaluronan Synthase 2/fibroblast growth factor 9 (HAS2/FGF9) axis.

Methods

Weighted gene co-expression network analysis (WGCNA) of the GSE23561 microarray dataset determined gene modules linked to CHD. The key genes were further explored through differential expression and protein-protein interaction (PPI) network analyses. Human AC16 cardiomyocytes were treated with Tan IIA, HAS2 knockdown, and FGF9 overexpression and they were exposed to normoxic, hypoxic, and I/R environments. Cell viability, apoptosis, gene/protein expression, and markers of oxidative stress were evaluated in vitro.

Results

The turquoise module was significantly correlated with CHD and HAS2 was identified as a hub gene. Under hypoxic conditions, Tan IIA exhibited a dose-dependent cardioprotective effect. Tan IIA ameliorated I/R-induced cellular injury, as evidenced by increased cell viability, decreased apoptosis, and regulation of key proteins (PCNA, Bax). After I/R conditions, knockdown of HAS2 increased cell viability and reduced apoptosis, whereas overexpression of FGF9 reversed these effects. Notably, HAS2 knockdown also ameliorated I/R-induced increases in inflammatory cytokines and oxidative stress, and synergistic protection was provided by combined treatment with FGF9 and Tan IIA.

Conclusion

Taken together, our findings confirm that Tan IIA protects cardiomyocytes from I/R-induced injury by controlling the HAS2/FGF9 axis. These findings reveal the potential therapeutic significance of Tan IIA in alleviating CHD-related myocardial dysfunction.

Protection of Ndrg2 deficiency on renal ischemia-reperfusion injury via activating PINK1/Parkin-mediated mitophagy

BACKGROUND

Renal ischemia-reperfusion (R-I/R) injury is the most prevalent cause of acute kidney injury, with high mortality and poor prognosis. However, the underlying pathological mechanisms are not yet fully understood. Therefore, this study aimed to investigate the role of N-myc downstream-regulated gene 2 ( Ndrg2 ) in R-I/R injury.

METHODS

We examined the expression of Ndrg2 in the kidney under normal physiological conditions and after R-I/R injury by immunofluorescence staining, real-time polymerase chain reaction, and western blotting. We then detected R-I/R injury in Ndrg2-deficient ( Ndrg2-/- ) mice and wild type ( Ndrg2+/+ ) littermates in vivo , and detected oxygen and glucose deprivation and reperfusion (OGD-R) injury in HK-2 cells. We further conducted transcriptomic sequencing to investigate the role of Ndrg2 in R-I/R injury and detected levels of oxidative stress and mitochondrial damage by dihydroethidium staining, biochemical assays, and western blot. Finally, we measured the levels of mitophagy in Ndrg2+/+ and Ndrg2-/- mice after R-I/R injury or HK-2 cells in OGD-R injury.

RESULTS

Ndrg2 was primarily expressed in renal proximal tubules and its expression was significantly decreased 24 h after R-I/R injury. Ndrg2-/- mice exhibited significantly attenuated R-I/R injury compared to Ndrg2+/+ mice. Transcriptomics profiling showed that Ndrg2 deficiency induced perturbations of multiple signaling pathways, downregulated inflammatory responses and oxidative stress, and increased autophagy following R-I/R injury. Further studies revealed that Ndrg2 deficiency reduced oxidative stress and mitochondrial damage. Notably, Ndrg2 deficiency significantly activated phosphatase and tensin homologue on chromosome ten-induced putative kinase 1 (PINK1)/Parkin-mediated mitophagy. The downregulation of NDRG2 expression significantly increased cell viability after OGD-R injury, increased the expression of heme oxygenase-1, decreased the expression of nicotinamide adenine dinucleotide phosphate oxidase 4, and increased the expression of the PINK1/Parkin pathway.

CONCLUSION

Ndrg2 deficiency might become a therapy target for R-I/R injury by decreasing oxidative stress, maintaining mitochondrial homeostasis, and activating PINK1/Parkin-mediated mitophagy.

An Effective Treatment of Fulminant Hepatic Failure: A Single-Center Retrospective Study

OBJECTIVES

Fulminant hepatic failure is a critical condition with a high mortality rate. Currently, liver transplantation is considered one of the most effective treatment methods, but the shortage of organ resources has presented a major obstacle. The use of marginal donor livers, including those from syphilis-positive donors, offers new opportunities. This study reviewed and analyzed data from our center to summarize the management experience of using syphilis-positive donor livers to treat fulminant hepatic failure.

MATERIALS AND METHODS

From January 2016 to December 2021, 17 adult patients with fulminant hepatic failure received liver transplants from syphilis-positive donors at our center. Given the imbalance in several baseline variables, propensity score matching was used. We compared outcomes, including complications, hospital stay, recovery of liver function, and survival rates between groups of patients with syphilis-positive and syphilis-negative grafts. We also reviewed treatment of recipients of syphilis-positive livers.

RESULTS

No significant differences were shown in complications and hospital stays between recipients of syphilis-positive and syphilis-negative grafts. Both groups showed similar trends in liver function recovery. Patient and graft survival rates were comparable between the groups. Benzathine penicillin effectively protected recipients from syphilis.

CONCLUSIONS

Use of liver grafts from syphilis-positive donors did not increase morbidity and mortality in recipients. Liver transplant can effectively treat patients with fulminant hepatic failure. In addition, prophylactic use of benzathine penicillin was beneficial.

Charge balanced aggregation: A universal approach to aqueous organic nanocrystals

Organic nanocrystals, particularly those composed of conjugated molecules, hold immense potential for various applications. However, their practical utility is often hindered by the challenge of achieving stable aqueous dispersions, which are essential for biological compatibility and effective delivery. This study introduces a novel and versatile strategy for preparing stable aqueous organic nanocrystals using a modified reprecipitation method. We demonstrate the broad applicability of this approach by successfully preparing a diverse library of nanocrystals from 27 conjugated molecules. Our findings reveal a charge-balanced aggregation mechanism for nanocrystal formation, highlighting the crucial role of surface charge in controlling particle size and stability. Based on this mechanism, we establish a comprehensive molecular combination strategy that directly links molecular properties to colloidal behaviour, enabling the straightforward prediction and preparation of stable aqueous dispersions without the need for excipients. This strategy provides a practical workflow for tailoring the functionality of these nanocrystals for a wide range of applications. To illustrate their therapeutic potential, we demonstrate the enhanced efficacy of these nanocrystals in treating acute ulcerative colitis, myocardial ischemia/reperfusion injury, and cancer in mouse models. This work paves the way for developing next-generation nanomaterials with tailored functionalities for diverse biomedical applications.

Extrarenal Visceral Arteries Injuries during Left Radical Nephrectomy: A 50-Year Continuing Problem

Due to their proximity to the left renal hilum, injuries to the superior mesenteric artery and celiac trunk are still reported during left radical nephrectomy, whether performed via open, laparoscopic, or robotic methods. The aim of this 50-year narrative review is to emphasize the anatomical and pathophysiological bases, risk factors, and strategies for the prevention, diagnosis, and treatment of such injuries.

The Crucial Triad: Endothelial Glycocalyx, Oxidative Stress, and Inflammation in Cardiac Surgery-Exploring the Molecular Connections

Since its introduction, the number of heart surgeries has risen continuously. It is a high-risk procedure, usually involving cardiopulmonary bypass, which is associated with an inflammatory reaction that can lead to perioperative and postoperative organ dysfunction. The extent of complications following cardiac surgery has been the focus of interest for several years because of their impact on patient outcomes. Recently, numerous scientific efforts have been made to uncover the complex mechanisms of interaction between inflammation, oxidative stress, and endothelial dysfunction that occur after cardiac surgery. Numerous factors, such as surgical and anesthetic techniques, hypervolemia and hypovolemia, hypothermia, and various drugs used during cardiac surgery trigger the development of systemic inflammatory response and the release of oxidative species. They affect the endothelium, especially endothelial glycocalyx (EG), a thin surface endothelial layer responsible for vascular hemostasis, its permeability and the interaction between leukocytes and endothelium. This review highlights the current knowledge of the molecular mechanisms involved in endothelial dysfunction, particularly in the degradation of EG. In addition, the major inflammatory events and oxidative stress responses that occur in cardiac surgery, their interaction with EG, and the clinical implications of these events have been summarized and discussed in detail. A better understanding of the complex molecular mechanisms underlying cardiac surgery, leading to endothelial dysfunction, is needed to improve patient management during and after surgery and to develop effective strategies to prevent adverse outcomes that complicate recovery.

Loureirin B improves H/R-induced hepatic ischemia-reperfusion injury by downregulating ALOX5 to regulate mitochondrial homeostasis

This study was conceived to explore the role and the mechanism of Loureirin B (LB) in hepatic IRI. The viability of LB-treated AML-12 cells was assessed using CCK-8 assay and inflammatory cytokines were detected using ELISA. The activities of ROS and oxidative stress markers MDA, SOD, and GSH-Px were detected using DCFH-DA and corresponding assay kits. The cell apoptosis and caspase3 activity were estimated with flow cytometry and caspase3 assay kits. The expressions of arachidonate 5-lipoxygenase (ALOX5) and apoptosis- and mitochondrial dynamics-related proteins were detected using western blot. The interaction between LB and ALOX5 was analyzed with molecular docking. The transfection efficacy of oe-ALOX5 was examined with RT-qPCR and western blot. Mitochondrial membrane potential was detected with JC-1 staining and immunofluorescence (IF) assay was employed to estimate mitochondrial fusion and fission. The present work found that LB revived the viability, inhibited inflammatory response, suppressed oxidative stress, repressed the apoptosis, and maintained mitochondrial homeostasis in H/R-induced AML-12 cells, which were all reversed by ALOX5 overexpression. Collectively, LB regulated mitochondrial homeostasis by downregulating ALOX5, thereby improving hepatic IRI.

Acacetin is a Promising Drug Candidate for Cardiovascular Diseases

Phytochemical flavonoids have been proven to be effective in treating various disorders, including cardiovascular diseases. Acacetin is a natural flavone with diverse pharmacological effects, uniquely including atrial-selective anti-atrial fibrillation (AF) via the inhibition of the atrial specific potassium channel currents [Formula: see text] (ultra-rapidly delayed rectifier potassium current), [Formula: see text] (acetylcholine-activated potassium current), [Formula: see text] (calcium-activated small conductance potassium current), and [Formula: see text] (transient outward potassium current). [Formula: see text] inhibition by acacetin, notably, suppresses experimental J-wave syndromes. In addition, acacetin provides extensive cardiovascular protection against ischemia/reperfusion injury, cardiomyopathies/heart failure, autoimmune myocarditis, pulmonary artery hypertension, vascular remodeling, and atherosclerosis by restoring the downregulated intracellular signaling pathway of Sirt1/AMPK/PGC-1α followed by increasing Nrf2/HO-1/SOD thereby inhibiting oxidation, inflammation, and apoptosis. This review provides an integrated insight into the capabilities of acacetin as a drug candidate for treating cardiovascular diseases, especially atrial fibrillation and cardiomyopathies/heart failure.

Bibliometric analysis of skeletal muscle ischemia/reperfusion (I/R) research from 1986 to 2022

Introduction

Tissue damage due to ischemia and reperfusion is a critical medical problem worldwide. Studies in this field have made remarkable advances in understanding the pathogenesis of ischemia/reperfusion (I/R) injury and its treatment with new and known drugs. However, no bibliometric analysis exists in this area of research.

Methods

Research articles and reviews related to skeletal muscle I/R from 1986 to 2022 were retrieved from the Web of Science Core Collection. Bibliometric analysis was performed using Microsoft Excel 2019, VOSviewer (version 1.6.19), Bibliometrix (R-Tool for R-Studio), and CiteSpace (version 6.1.R5).

Results

A total of 3682 research articles and reviews from 2846 institutions in 83 countries were considered in this study. Most studies were conducted in the USA. Hobson RW (UMDNJ-New Jersey Medical School) had the highest publication, and Korthuis RJ (Louisiana State University) had the highest co-citations. Our analysis showed that, though the Journal of Surgical Research was most favored, the Journal of Biological Chemistry had the highest number of co-citations. The pathophysiology, interventions, and molecular mechanisms of skeletal muscle I/R injury emerged as the primary research areas, with "apoptosis," "signaling pathway," and "oxidative stress" as the main keywords of research hotspots.

Conclusions

This study provides a thorough overview of research trends and focal points in skeletal muscle I/R injury by applying bibliometric and visualization techniques. The insights gained from our findings offer a profound understanding of the evolving landscape of skeletal muscle I/R injury research, thereby functioning as a valuable reference and roadmap for future investigations.

Role of Mitochondrial Dysfunctions in Neurodegenerative Disorders: Advances in Mitochondrial Biology

Mitochondria, essential organelles responsible for cellular energy production, emerge as a key factor in the pathogenesis of neurodegenerative disorders. This review explores advancements in mitochondrial biology studies that highlight the pivotal connection between mitochondrial dysfunctions and neurological conditions such as Alzheimer's, Parkinson's, Huntington's, ischemic stroke, and vascular dementia. Mitochondrial DNA mutations, impaired dynamics, and disruptions in the ETC contribute to compromised energy production and heightened oxidative stress. These factors, in turn, lead to neuronal damage and cell death. Recent research has unveiled potential therapeutic strategies targeting mitochondrial dysfunction, including mitochondria targeted therapies and antioxidants. Furthermore, the identification of reliable biomarkers for assessing mitochondrial dysfunction opens new avenues for early diagnosis and monitoring of disease progression. By delving into these advancements, this review underscores the significance of understanding mitochondrial biology in unraveling the mechanisms underlying neurodegenerative disorders. It lays the groundwork for developing targeted treatments to combat these devastating neurological conditions.

Inflammatory setting, therapeutic strategies targeting some pro-inflammatory cytokines and pathways in mitigating ischemia/reperfusion-induced hepatic injury: a comprehensive review

Ischemia/reperfusion injury (IRI) is a key determining agent in the pathophysiology of clinical organ dysfunction. It is characterized by an aseptic local inflammatory reaction due to a decrease in blood supply, hence deprivation of dependent oxygen and nutrients. In instances of liver transplantation, this injury may have irreversible implications, resulting in eventual organ rejection. The deterioration associated with IRI is affected by the hepatic health status and various factors such as alterations in metabolism, oxidative stress, and pro-inflammatory cytokines. The primary cause of inflammation is the initial immune response of pro-inflammatory cytokines, while Kupffer cells (KFCs) and neutrophil-produced chemokines also play a significant role. Upon reperfusion, the activation of inflammatory responses can elicit further cellular damage and organ dysfunction. This review discusses the interplay between chemokines, pro-inflammatory cytokines, and other inflammatory mediators that contribute to the damage to hepatocytes and liver failure in rats following IR. Furthermore, it delves into the impact of anti-inflammatory therapies in safeguarding against liver failure and hepatocellular damage in rats following IR. This review investigates the correlation between cytokine factors and liver dysfunction via examining databases, such as PubMed, Google Scholar, Science Direct, Egyptian Knowledge Bank (EKB), and Research Gate.

The Protective Role of Molecular Hydrogen in Ischemia/Reperfusion Injury

Ischemia/reperfusion injury (IRI) represents a significant contributor to morbidity and mortality associated with various clinical conditions, including acute coronary syndrome, stroke, and organ transplantation. During ischemia, a profound hypoxic insult develops, resulting in cellular dysfunction and tissue damage. Paradoxically, reperfusion can exacerbate this injury through the generation of reactive oxygen species and the induction of inflammatory cascades. The extensive clinical sequelae of IRI necessitate the development of therapeutic strategies to mitigate its deleterious effects. This has become a cornerstone of ongoing research efforts in both basic and translational science. This review examines the use of molecular hydrogen for IRI in different organs and explores the underlying mechanisms of its action. Molecular hydrogen is a selective antioxidant with anti-inflammatory, cytoprotective, and signal-modulatory properties. It has been shown to be effective at mitigating IRI in different models, including heart failure, cerebral stroke, transplantation, and surgical interventions. Hydrogen reduces IRI via different mechanisms, like the suppression of oxidative stress and inflammation, the enhancement of ATP production, decreasing calcium overload, regulating cell death, etc. Further research is still needed to integrate the use of molecular hydrogen into clinical practice.

Skimmianine Showed Neuroprotection against Cerebral Ischemia/Reperfusion Injury

The aim of this study was to investigate the antioxidant and anti-inflammatory effects of skimmianine on cerebral ischemia-reperfusion (IR) injury. Twenty-four female Wistar albino rats were randomly divided into three groups: Sham, Ischemia-Reperfusion (IR), and IR + Skimmianine (40 mg/kg Skimmianine). Cerebral ischemia was induced using a monofilament nylon suture to occlude the middle cerebral artery for 60 min. Following 23 h of reperfusion, the animals were sacrificed 14 days later. The effects of skimmianine on brain tissue post-IR injury were examined through biochemical and immunochemical analyses. In silico analysis using the Enrichr platform explored skimmianine's potential biological processes involving IBA-1, IL-6, and NF-κB proteins. In the IR group, MDA levels increased, while SOD and CAT antioxidant enzyme activities decreased. In the IR + Skimmianine group, skimmianine treatment resulted in decreased MDA levels and increased SOD and CAT activities. Significant increases in IBA-1 expression were observed in the IR group, which skimmianine treatment significantly reduced, modulating microglial activation. High levels of IL-6 expression were noted in pyramidal neurons, vascular structures, and neuroglial cells in the IR group; skimmianine treatment reduced IL-6 expression, demonstrating anti-inflammatory effects. Increased NF-κB expression was observed in neurons and blood vessels in the gray and white matter in the IR group; skimmianine treatment reduced NF-κB expression. Gene Ontology results suggest skimmianine impacts immune and inflammatory responses via IBA-1 and IL-6, with potential effects on estrogen mechanisms mediated by NF-κB. Skimmianine may be a potential therapeutic strategy due to its antioxidant and anti-inflammatory effects on cerebral IR injury.

Effects of Cyclodextrin Curcumin Formulation on Ischemia-Reperfusion Injury in Porcine DCD Liver Transplantation

BACKGROUND

Curcumin is a pleiotropic antioxidant polyphenol, which has proven to be highly protective in various models of liver injury and inflammation. We hypothesized that adding a stable aqueous curcumin formulation which comprises a water-soluble cyclodextrin curcumin formulation (CDC) complex of the water-insoluble curcumin molecule (Novobion, Espoo, Finland) to preservation solution during liver procurement may reduce ischemia-reperfusion injury and improve graft function after liver transplantation using donation after circulatory death (DCD).

METHODS

In a preclinical pig model of DCD-liver transplantation, livers exposed to 15' of warm ischemia were either modulated (N = 6) with a flush of preservation solution (histidine-tryptophan-ketoglutarate) containing CDC (60 µmol/L) through the vena porta and the aorta, or not (controls, N = 6) before 4 h of cold storage. Area under the curve of log serum aspartate aminotransferase, markers of graft function (lactate, glycemia, prothrombin time, and bile production), inflammation (tumor necrosis factor-alpha), and survival were monitored.

RESULTS

Area under the curve of log serum aspartate aminotransferase were similar between curcumin and control groups (22.12 [20.87-24.88] versus 25.08 [22.1-26.55]; P = 0.28). No difference in the liver function markers were observed between groups except a lower serum lactate level 3-h post-reperfusion in the curcumin group (3 [1.95-6.07] versus 8.2 [4.85-13.45] mmol/L; P = 0.05). Serum tumor necrosis factor-alpha levels were similar in each group. Recipient survival rates were found similar.

CONCLUSIONS

CDC added to the preservation solution in DCD liver pig model did not improve ischemia-reperfusion injury severity, liver function, or survival. Further efforts are needed to explore this strategy, particularly with dynamic preservation, which finds its way into clinical practice.

[Soy isoflavones alleviates calcium overload in rats with cerebral ischemia-reperfusion by inhibiting the Wnt/Ca2+ signaling pathway]

OBJECTIVE

To explore the mechanism by which soybean isoflavone (SI) reduces calcium overload induced by cerebral ischemia-reperfusion (I/R).

METHODS

Forty-eight SD rats were randomized into 4 groups to receive sham operation, cerebral middle artery occlusion for 2 h followed by 24 h of reperfusion (I/R model group), or injection of adeno-associated virus carrying Frizzled-2 siRNA or empty viral vector into the lateral cerebral ventricle after modeling.Western blotting was used to examine Frizzled-2 knockdown efficiency and changes in protein expressions in the Wnt/Ca2+ signaling pathway.Calcium levels and pathological changes in the ischemic penumbra (IP) were measured using calcium chromogenic assay and HE staining, respectively.Another 72 SD randomly allocated for sham operation, I/R modeling, or soy isoflavones pretreatment before modeling were examined for regional cerebral blood flow using a Doppler flowmeter, and the cerebral infarct volume was assessed using TTC staining.Pathologies in the IP area were evaluated using HE and Nissl staining, and ROS level, Ca2+ level, cell apoptosis, and intracellular calcium concentration were analyzed using immunofluorescence assay or flow cytometry; the protein expressions of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP were detected with Western blotting and immunohistochemistry.

RESULTS

In rats with cerebral I/R, Frizzled-2 knockdown significantly lowered calcium concentration (P < 0.001) and the expression levels of Wnt5a, Frizzled-2, and P-CaMK Ⅱ in the IP area.In soy isoflavones-pretreated rats, calcium concentration, ROS and MDA levels, cell apoptosis rate, cerebral infarct volume, and expression levels of Wnt/Ca2+ signaling pathway-related proteins were all significantly lower while SOD level was higher than those in rats in I/R model group.

CONCLUSION

Soy isoflavones can mitigate calcium overload in rats with cerebral I/R by inhibiting the Wnt/Ca2+ signaling pathway.

Management of ROS and Regulatory Cell Death in Myocardial Ischemia-Reperfusion Injury

Myocardial ischemia-reperfusion injury (MIRI) is fatal to patients, leading to cardiomyocyte death and myocardial remodeling. Reactive oxygen species (ROS) and oxidative stress play important roles in MIRI. There is a complex crosstalk between ROS and regulatory cell deaths (RCD) in cardiomyocytes, such as apoptosis, pyroptosis, autophagy, and ferroptosis. ROS is a double-edged sword. A reasonable level of ROS maintains the normal physiological activity of myocardial cells. However, during myocardial ischemia-reperfusion, excessive ROS generation accelerates myocardial damage through a variety of biological pathways. ROS regulates cardiomyocyte RCD through various molecular mechanisms. Targeting the removal of excess ROS has been considered an effective way to reverse myocardial damage. Many studies have applied antioxidant drugs or new advanced materials to reduce ROS levels to alleviate MIRI. Although the road from laboratory to clinic has been difficult, many scholars still persevere. This article reviews the molecular mechanisms of ROS inhibition to regulate cardiomyocyte RCD, with a view to providing new insights into prevention and treatment strategies for MIRI.