Reperfusion injury and reactive oxygen species: The evolution of a concept

Flavonoids from Polypodium hastatum as neuroprotective agents attenuate cerebral ischemia/reperfusion injury in vitro and in vivo via activating Nrf2

OBJECTIVES

Cerebral ischemic stroke is a leading cause of death worldwide. Though timely reperfusion reduces the infarction size, it exacerbates neuronal apoptosis due to oxidative stress. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor regulating the expression of antioxidant enzymes. Activating Nrf2 gives a therapeutic approach to ischemic stroke.

METHODS

Herein we explored flavonoids identified from Polypodium hastatum as Nrf2 activators and their protective effects on PC12 cells injured by oxygen and glucose deprivation/restoration (OGD/R) as well as middle cerebral artery occlusion (MCAO) mice.

RESULTS

The results showed among these flavonoids, AAKR significantly improved the survival of PC12 cells induced by OGD/R and activated Nrf2 in a Keap1-dependent manner. Further investigations have disclosed AAKR attenuated oxidative stress, mitochondrial dysfunction and following apoptosis resulting from OGD/R. Meanwhile, activation of Nrf2 by AAKR was involved in the protective effects. Finally, it was found that AAKR could protect MCAO mice brains against ischemia/reperfusion injury via activating Nrf2.

DISCUSSION

This investigation could provide lead compounds for the discovery of novel Nrf2 activators targeting ischemia/reperfusion injury.

Understanding metabolic remodeling in shock through metabolomics lenses

The management of shock in critical care must transition from a predominantly hemodynamic approach to one that comprehensively addresses the biological intricacies of this complex multisystemic syndrome. A thorough understanding of the metabolic mechanisms involved in shock is pivotal for precise patient phenotyping and accurate risk stratification. Metabolomics, an emerging "-omics" approach, offers a powerful tool for unraveling the molecular underpinnings of shock. By analyzing the metabolic pathways within the cardiovascular system, metabolomics can elucidate the diverse mechanisms leading to circulatory insufficiency. This approach holds significant promise for identifying clinically actionable diagnostic and prognostic biomarkers, which can enhance individualized patient management and potentially prevent the progression to multi-organ failure. Improved insight into the metabolic alterations in shock may pave the way for novel therapeutic strategies and more targeted treatments, ultimately improving patient outcomes in critical care settings. This work provides a comprehensive overview of metabolomic investigations in shock, focusing on septic shock and the main metabolic pathways involved in cardiac and vascular dysfunction.

3,4-Dimethoxychalcone alleviates limb ischemia/reperfusion injury by TFEB-mediated autophagy enhancement and antioxidative response

Caloric restriction mimetics (CRMs) replicate the positive effects of caloric restriction (CR) and have demonstrated therapeutic benefits in neuroinflammatory and cardiovascular diseases. However, it remains uncertain whether CRMs enhance functional recovery following ischemia/reperfusion (I/R) injury, as well as the specific mechanisms involved in this process. This study examines the therapeutic potential of the CRM 3,4-dimethoxychalcone (3,4-DC) in limb I/R injury. Histology, tissue swelling analysis, and laser doppler imaging (LDI) were used to assess the viability of the limbs. Western blotting and immunofluorescence were utilized to examine apoptosis levels, oxidative stress (OS), autophagy, transcription factor EB (TFEB) activity, and mucolipin 1 (MCOLN1)-calcineurin signaling pathway. The administration of 3,4-DC notably alleviated hypoperfusion, tissue swelling, skeletal muscle fiber damage, and cellular injury in the limb caused by I/R. The pharmacological blockade of autophagy negated the antioxidant and antiapoptotic effects of 3,4-DC. Moreover, RNA interference-mediated TFEB silencing eliminated the 3,4-DC-induced restoration of autophagy, antioxidant response, and antiapoptotic effects. Additionally, our findings revealed that 3,4-DC modulates TFEB activity via the MCOLN1-calcineurin signaling pathway. 3,4-DC facilitates functional recovery by enhancing TFEB-driven autophagy, while simultaneously suppressing oxidative stress and apoptosis following I/R injury, suggesting its potential value in clinical applications.

A study of the association between Helicobacter pylori infection type and pancreatic cancer risk: A systematic review and meta‑analysis

Pancreatic cancer is a highly invasive malignant tumor with a complex pathogenesis that makes early diagnosis challenging. The potential association between Helicobacter pylori infection and pancreatic cancer risk has been noted; however, the available results are still highly divergent. The aim of the present study was to systematically evaluate the association between different types of H. pylori infection and pancreatic cancer risk as well as to explore the possible causes. A systematic search was conducted using the PubMed, Embase and Cochrane Library databases up to August 2023. The literature quality was evaluated using the Newcastle-Ottawa Scale. All studies that met the criteria were included in the overall meta-analysis to calculate the odds ratios (ORs) and corresponding 95% confidence intervals (CIs). In addition, subgroup analyses were performed based on factors such as diagnostic criteria for H. pylori infection, study region, type of study design and CagA status. The effect of publication bias on the quantitative synthesis results was assessed using the trim-and-fill analysis, and sensitivity analyses were used to verify the robustness of the quantitative synthesis results. A total of 17 studies involving 67,910 participants, including 64,372 controls and 3,538 patients with pancreatic cancer, were included in the present study. The overall analysis showed that no significant association was observed between H. pylori infection and pancreatic cancer risk (OR, 1.15; 95% CI, 0.93-1.41). Further subgroup analyses, which did not consider the effects of study quality, diagnostic criteria, geographical distribution and the type of study design, did not produce new findings that contradicted the results of the overall analysis. CagA+ H. pylori infection did not significantly affect the risk of pancreatic cancer (OR, 0.95; 95% CI, 0.78-1.16), whereas CagA- H. pylori infection may be a possible risk factor for pancreatic cancer (OR, 1.24; 95% CI, 1.004-1.541). The H. pylori infection did not significantly increase the risk of pancreatic cancer. However, it is noteworthy that CagA- H. pylori infection could be a potential factor that elevated the risk of pancreatic cancer.

Intermittent hypoxic stimulation promotes efficient expression of Hypoxia-inducible factor-1α and exerts a chondroprotective effect in an animal osteoarthritis model

Hypoxia-inducible factor-1α plays an important role in the homeostasis of articular cartilage in hypoxic environments. Therefore, modulation of hypoxia-inducible factor-1α by regulating the oxygen environment could be a useful treatment for osteoarthritis. This study aimed to assess the chondroprotective effects of intermittent hypoxia on cultured chondrocytes and an animal model of osteoarthritis. In vitro, human chondrocytes were exposed to 2 h of hypoxic stimulation three times at 1-h intervals, and protein and gene expression of hypoxia-inducible factor-1α, ACAN, and cell viability was measured over time. In vivo, 8-week-old male Wistar rats were injected with monosodium iodoacetate to induce osteoarthritis and then reared in 12% hypoxia for 24 h, followed by 24 h in steady oxygen, repeated alternately for a total of 28 days. A histological analysis was performed on days 8 and 28. In the intermittent hypoxia group, each protein expression increased with each repeated hypoxic stimulation to human chondrocytes; finally, the protein level was significantly higher with intermittent hypoxia than with continuous hypoxic stimulation, cell viability was increased, and gene expression was not significantly increased. In the osteoarthritis animal model, for 8 days, there were stronger hypoxia-inducible factor-1α staining and no significant differences in articular cartilage destruction. Furthermore, for 28 days, there was significantly less articular cartilage destruction in the rat osteoarthritis model with intermittent hypoxia than with steady oxygen rearing. Intermittent hypoxia increased cartilage metabolism by increasing hypoxia-inducible factor-1α proteins in articular chondrocytes, which may be effective in preventing articular cartilage degeneration in a rat osteoarthritis model.

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.

Therapeutic S100A8/A9 inhibition reduces NADPH oxidase expression, reactive oxygen species production and NLRP3 inflammasome priming in the ischemic myocardium

Oxidative stress and alterations in redox signalling have been implicated in the pathophysiology of myocardial infarction (MI). NADPH oxidase (Nox) is an important source of reactive oxygen species (ROS) in the infarcted myocardium. Alarmin S100A8/A9 amplifies acute myocardial inflammation in MI and has been shown to be a promising therapeutic target to improve cardiac function post-MI. We aimed to elucidate the underlying mechanisms linking S100A8/A9, oxidative stress and the inflammatory response in MI. MI was induced by permanent left coronary artery ligation in C57BL/6J mice, followed by treatment with the S100A8/A9 inhibitor ABR-238901 (30 mg/kg) or PBS for 3 days. The in-vivo experiments were complemented with mechanistic studies on cultured macrophages (Mac), important cellular effectors in MI. Compared to sham-operated animals, we detected significant increases in the Nox1, Nox2, Nox4 catalytic subunits at mRNA and protein levels, and NADPH-dependent ROS production in the left ventricle of MI mice. S100A8/A9 blockade prevented the up-regulation of Nox1/2/4 expression, reduced ROS formation, suppressed NF-kB activation and prevented NLRP3 inflammasome priming and activation, leading to reduced levels of active IL-1β. In-vitro, S100A8/A9 induced gene expression of Nox catalytic subtypes and NLRP3 in Mac in a TLR4-dependent and dose-dependent manner. These effects were counteracted by pharmacological inhibition of S100A8/9, TLR4, Nox1/4 and Nox2. In conclusion, we show that Nox upregulation and ROS formation triggered by S100A8/A9 contributes to NLRP3 inflammasome priming and increased IL-1β production in the infarcted myocardium. These mechanisms can be therapeutically targeted to prevent inflammatory and oxidant myocardial damage in acute MI.

Liriodendrin alleviates myocardial ischemia‑reperfusion injury via partially attenuating apoptosis, inflammation and mitochondria damage in rats

Myocardial ischemia‑reperfusion (I/R) injury may lead to dysfunction of signaling pathways related to cell apoptosis, inflammation, oxidative stress, and mitochondrial damage. The present study investigated the defensive effect of liriodendrin, as a natural product isolated from Linaria vulgaris, on reperfusion injury in rats and the underlying mechanisms involved in this process. An in vivo rat model of I/R constructed by ligation of the left anterior descending artery, as well as an in vitro model using H9C2 cells under hypoxic conditions, was established to assess the cardioprotective effects of liriodendrin. The biomarkers of myocardial damage, oxidative stress, and inflammatory response were measured with enzyme‑linked immunosorbent assay (ELISA). Gene and protein expression were detected by reverse transcription‑quantitative PCR (RT‑qPCR) and western blotting. Mitochondrial morphology was observed by electron microscopy. The levels of creatine kinase isoenzymes and cardiac troponin T were significantly elevated in the I/R compared with the sham group; liriodendrin mitigated this elevation. The liriodendrin group exhibited a significant reduction in myocardial tissue apoptosis, as indicated by immunohistochemical staining and western blotting. Additionally, ELISA indicated that the I/R group had higher levels of reactive oxygen species (ROS) compared with the liriodendrin group, while the liriodendrin group had higher levels of superoxide dismutase. The in vitro experiments demonstrated that liriodendrin ameliorated hypoxia‑induced injury to mitochondria and suppressed the activation of nuclear factor-κB and B-cell lymphoma-2 associated X protein (Bax). Therefore, the present study demonstrated that liriodendrin impeded ROS‑associated metabolic disorders, maintained mitochondrial homeostasis and partially alleviated cardiomyocyte apoptosis by inhibiting the Bax signaling pathway.

Indolizine Derivatives Inhibit TRPM2 and Protect against Ischemic Brain Injury with an Extended Treatment Window

Ischemic stroke, a major cause of disability and death worldwide, lacks effective treatments due to the complexity of brain ischemia/reperfusion (I/R) injury. The transient receptor potential melastatin 2 (TRPM2) channel is a promising therapeutic target. In this study, an extracellular TRPM2 inhibitor A1 with an indolizine scaffold was identified through chemical library screening. Four series of indolizine derivatives were synthesized, yielding four compounds with TRPM2 inhibitory activity comparable to or superior to A1, as confirmed by calcium fluorescence and electrophysiological assays. These compounds demonstrated significant neuroprotective effects in vitro. Among them, D10 showed robust efficacy in reducing cerebral infarction in a transient middle cerebral artery occlusion (tMCAO) model, surpassing edaravone. When administered 24 h postreperfusion and continued for 7 days, D10 exhibited sustained in vivo antistroke activity and improved survival rates compared to edaravone and vehicle controls. D10 represents a promising lead compound for ischemic stroke therapy.

Mitigating hepatic ischemia and reperfusion injury with polyethylene glycol-enriched Ringer's lactate fluid: insights from an isolated perfused rat model

BACKGROUND

Cold ischemia-reperfusion (IR) injury is a multifactorial process detrimental to liver graft function during liver transplantation (LT). Although flushing hepatic grafts prior to reperfusion have been well explored, the optimal graft rinse solution to prevent cold IR injury remains largely undefined. The aim of this study was to evaluate whether a new rinse solution combining polyethylene glycol PM 35,000 Da (PEG35) with lactated solution (RLS) could mitigate cold IR injury in Wistar rats.

METHODS

Livers were isolated, preserved for 24 h and flushed immediately before ex vivo reperfusion with either RLS or PEG35-enriched RLS. Liver injury, graft function, energy balance, autophagy, oxidative stress as well as inflammatory response were assessed.

RESULTS

Flushing hepatic grafts with PEG35-enriched RLS resulted in decreased transaminase levels after cold ischemia. The improved graft function was evidenced by increased bile flow, enhanced BSP clearance, and reduced vascular resistance in these flushed grafts. Phospho-AMPK protein expression, as well as LC3B gene and protein expression were significantly increased compared to those unflushed and flushed only with RLS. PEG35-enriched RLS also maintained the oxidative state, as indicated by reduced activities of antioxidant enzymes and decreased MDA concentration. Additionally, this graft rinse solution down-regulated the inflammatory response by inhibiting the expression of genes involved in the HMGB-1/NF-κB/TNF-α signaling pathway.

CONCLUSION

These data strongly suggest that rinsing liver grafts with PEG35-enriched RLS prior to reperfusion represents a simple and cost-effective strategy to enhance liver functional recovery after cold IR injury. This approach could serve as a viable alternative to RLS in clinical applications, highlighting the need for further research to explore its broader implications.

Comparative analysis of cold-stored platelets using Golden Hour transport boxes: Function and quality

BACKGROUND

The Emergency Medical Retrieval and Transfer Service in Wales provides prehospital critical care, including the transfusion of red blood cells and plasma. However, the logistical challenges of storing platelet concentrates (PCs) at 22°C with constant agitation limit their prehospital use. Cold-stored platelets (CSP) at 4°C without agitation offer a potential solution, demonstrating superior hemostatic capabilities in vitro and longer storage potential. This study investigated the viability of storing CSP in Golden Hour boxes for up to 96 h, followed by refrigeration, to enhance prehospital damage control resuscitation.

METHODS

Two buffy-coat-derived PCs were combined and split into two: one PC was refrigerated at 4°C ± 2°C without agitation (CSP) for 15 days, and the other was stored in a Golden Hour cold box from days 2 to 6 (GH-CSP) before being rotated back into refrigeration. In vitro assessments included aggregometry, thrombin generation, thromboelastography, and platelet activation via P-selectin and annexin V binding.

RESULTS

Temperature data demonstrated that a Golden Hour box can maintain a temperature of 2-6°C for up to 84 h with a CSP and two red cell concentrates. Platelet function was not significantly different between the two storage conditions. GH-CSP displayed increased annexin V binding on day 8 compared with CSP (32.31 ± 3.27% vs 26.36 ± 2.17%, p = .0026) and day 15 (41.76 ± 6.13% vs 38.41 ± 3.99%, p = .0199).

CONCLUSION

CSP stored in a Golden Hour box was comparable with conventional CSP, suggesting this method may be viable for prehospital use.

Melatonin-mediated adaptation of spinach (Spinacia oleracea L.) in acidic soil

Soil acidity is a widespread and critical factor contributing to soil degradation. Melatonin (MT) as a protective biostimulant, plays a crucial role in plant growth under harsh environments. However, the role of MT in plant adaptation to acidic soil remains elusive. Hence, here we tested the effects of exogenous MT on the adaptation of spinach (Spinacia oleracea L.) crop to acidic soil (pH 4.0). Initially, a series of MT concentrations (0, 25, 50, 100, and 200 μM) were tested to evaluate the seed germination and growth attributes of spinach under low pH levels. Among the doses, 100 μM MT showed better results in terms of germination percentage and biomass accumulation, which was then selected for further experiments. Results showed that exogenous MT significantly increased plant adaptation to acidic soil as evidenced by increased photosynthesis rate and biomass accumulation with enhanced total antioxidant capacity, DPPH free radical scavenging, phenol, flavonoid, and glutathione contents compared with soil acidity treatment alone. Moreover, MT alleviated oxidative stress indices such as electrolyte leakage and malondialdehyde in acid-stressed plants, suggesting an effective strategy of adaptation. Furthermore, MT-treated plants exhibited higher macro and micronutrient accumulation along with higher vitamin B complex, vitamin C, and protein content, leading to an increased nutritional quality and yield compared to control. Therefore, the study concludes that the application of MT at 100 μM could be a sustainable alternative approach to adapt spinach farming in acidic soil.

Mechanism of LCN2 in cerebral ischemia-reperfusion injury

Cerebral ischemia-reperfusion injury (CIRI) is a complex pathophysiological process faced by brain tissues after ischemic stroke treatment, which involves mechanisms of inflammatory response, oxidative stress and apoptosis, and severely affects treatment outcome. Lipocalin-2 (LCN2), an acute-phase protein, is significantly up-regulated after CIRI and promotes neural repair by enhancing astrocyte phagocytosis, but its over-activation may also trigger secondary inflammation and demyelination injury. LCN2 also plays a key role in neuroinflammation regulation by regulating the polarization state of astrocytes and the release of inflammatory factors, and may affect the integrity of the blood-brain barrier and a variety of pathologic injury processes. In view of the important role of LCN2 in CIRI, this article reviews the mechanism of LCN2, aiming to provide new ideas and methods for the treatment of ischemic stroke.

Ready to dive? Early constraints help juvenile southern elephant seals (Mirounga leonina) acclimatize to aquatic life

Breath-holding foraging implies different adaptations to limit oxygen (O2) depletion and maximize foraging time. Physiological adjustments can be mediated through O2 consumption, driven by muscle mitochondria, which can also produce reactive oxygen species during reoxygenation. Southern elephant seals spend months foraging at sea, diving for up to 1 h. Pups transition abruptly to aquatic life after a post-weaning period, during which they fast and progressively increase their activity, making this period critical for the development of an adaptive response to oxygen restriction and oxidative stress. We compared the functional capacity of a swimming muscle in 5 recently weaned and 6 adult female southern elephant seals. High-resolution respirometry was employed to examine muscle mitochondrial respiratory capacity and differences in protein and gene expression of the main regulatory pathways were determined using LC-MS/MS and RT-qPCR, respectively. Oxidative damage was measured in the plasma. We found that juveniles have higher mitochondrial coupling efficiency compared with adults, probably as a response to growth and significant physical activity reported during the post-weaning period. There were no differences in oxidative damage, but adults had a higher level of antioxidant defenses. Both hypoxia and oxidative response pathways appeared less activated in juveniles. This study highlights the differences in muscle metabolism and the likely adaptive response to hypoxia and oxidative stress between juvenile and adult south elephant seals. It also suggests that early constraints such as fasting, physical activity and short-term low O2 partial pressure exposure could contribute to immediate and long-term responses and help to acclimatize juveniles to aquatic life.

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.

Lactylation: a promising therapeutic target in ischemia-reperfusion injury management

Ischemia-reperfusion injury (IRI) is a critical condition that poses a significant threat to patient safety. The production of lactate increases during the process of IRI, and lactate serves as a crucial indicator for assessing the severity of such injury. Lactylation, a newly discovered post-translational modification in 2019, is induced by lactic acid and predominantly occurs on lysine residues of histone or nonhistone proteins. Extensive studies have demonstrated the pivotal role of lactylation in the pathogenesis and progression of various diseases, including melanoma, myocardial infarction, hepatocellular carcinoma, Alzheimer's disease, and nonalcoholic fatty liver disease. Additionally, a marked correlation between lactylation and inflammation has been observed. This article provides a comprehensive review of the mechanism underlying lactylation in IRI to establish a theoretical foundation for better understanding the interplay between lactylation and IRI.

Asymptomatic Hemorrhagic Events and Functional Outcomes in Acute Stroke: A Secondary Analysis of the DIRECT-MI Randomized Clinical Trial

Importance

Asymptomatic hemorrhagic infarction (HI) and subarachnoid hemorrhage (SAH) after endovascular treatment (EVT) for acute ischemic stroke are commonly considered low risk, but their long-term impact on functional outcomes is unclear.

Objective

To determine whether asymptomatic HI and SAH are associated with worse 90-day functional recovery in patients with acute ischemic stroke treated with EVT.

Design, Setting, and Participants

This is a secondary analysis of the DIRECT-MT randomized clinical trial, which compared intravenous thrombolysis prior to EVT with EVT alone. The multicenter study was conducted at tertiary hospitals in China between 2016 and 2019 with 90-day follow-up. Trial patients with asymptomatic HI, SAH, or no hemorrhage were included in the present analysis, which was performed in December 2024.

Exposure

Asymptomatic HI and SAH detected on follow-up imaging.

Main Outcomes and Measures

The primary outcome was the score on the modified Rankin scale (mRS) assessed at 90 days. Secondary analyses categorized mRS scores into thresholds of 0 to 1, 0 to 2, and 0 to 3, representing excellent, good, and favorable recovery, respectively.

Results

A total of 490 patients were included (median [IQR] age, 70 [60-76] years; 210 [42.9%] female), with 133 (27.1%) in the asymptomatic HI and SAH group and 357 (72.9%) in the no hemorrhage group. After propensity score matching, the odds ratio of having a worse mRS scores at 90 days in the asymptomatic HI and SAH group compared with the no hemorrhage group was 2.59 (95% CI, 1.45-4.63; P = .001). For binary outcomes, asymptomatic HI and SAH were consistently associated with worse recovery across mRS score thresholds of 0 to 1 and 0 to 2 in all models.

Conclusions and Relevance

In this secondary analysis of a randomized clinical trial, asymptomatic HI and SAH were associated with worse 90-day functional outcomes in patients with acute ischemic stroke treated with EVT. These findings emphasize the need for close monitoring and tailored management strategies in patients with asymptomatic hemorrhagic events following thrombectomy.

Trial Registration

ClinicalTrials.gov Identifier: NCT03469206.

Vascular actions of Ang 1-7 and Ang 1-8 through EDRFs and EDHFs in non-diabetes and diabetes mellitus

The renin-angiotensin system (RAS) plays a pivotal role in regulating vascular homeostasis, while angiotensin 1-8 (Ang 1-8) traditionally dominates as a vasoconstrictor factor. However, the discovery of angiotensin 1-7 (Ang 1-7) and Ang 1-8 has revealed counter-regulatory mechanisms mediated through endothelial-derived relaxing factors (EDRFs) and endothelial-derived hyperpolarizing factors (EDHFs). This review delves into the vascular actions of Ang 1-7 and Ang 1-8 in both non-diabetes mellitus (non-DM) and diabetes mellitus (DM) conditions, highlighting their effects on vascular endothelial cell (VECs) function as well. In a non-DM vasculature context, Ang 1-8 demonstrate dual effect including vasoconstriction and vasodilation, respectively. Additionally, Ang 1-7 induces vasodilation upon nitric oxide (NO) production as a prominent EDRFs in distinct mechanisms. Further research elucidating the precise mechanisms underlying the vascular actions of Ang 1-7 and Ang 1-8 in DM will facilitate the development of tailored therapeutic interventions aimed at preserving vascular health and preventing cardiovascular complications.

Review: Hormone Pregnancy Tests Were Teratogenic by the Same Failed Abortion and Hypoxia-Related Mechanism as Misoprostol

INTRODUCTION

Hormone pregnancy tests (HPTs), containing synthetic progesterone and oestrogen, were used to diagnose pregnancy in the 1950s to early 1980s. An existing pregnancy was purported to be unaffected while expulsion of the uterine lining (withdrawal bleed) was supposed to occur if the woman was not pregnant. However, studies in the 1960s-1980s associated HPTs with teratogenicity and some countries banned their use in the early 1970s. Following renewed scientific and political interest, studies were published from 2014-2023.

MATERIALS AND METHODS

This review evaluates whether HPTs fulfil scientific criteria to be teratogenic based on results in old and newer human, animal and mechanistic studies.

RESULTS AND DISCUSSION

The evaluation shows that HPT teratogenicity is identical to the established human teratogen misoprostol, with limb reductions, neural tube defects and urinary-renal system defects as the most significant. The evaluation also presents evidence for abnormal uterine contractions and failed abortion (but the embryo survives) and hypoxia/ROS-related damage (including vascular disruption) in the embryo secondary to compression of uterine/embryonic vessels, as underlying the teratogenicity. Animal studies show human malformations associated with HPTs could be induced by a single period of embryonic hypoxia, and that HPTs have both abortive and teratogenic potential.

CONCLUSION

Altogether, HPTs fulfil criteria to be characterised as a human teratogen.

Inhibition of Phosphodiesterase 4 Suppresses Neuronal Ferroptosis After Cerebral Ischemia/Reperfusion

We have previously shown that inhibition of phosphodiesterase 4 (PDE4) protects against cerebral ischemia/reperfusion injury. However, it remains unclear whether and how PDE4 affects ferroptosis under cerebral ischemia/reperfusion conditions. In this study, we found that overexpression of PDE4B in HT-22 cells exacerbated the detrimental effects of oxygen-glucose deprivation/reoxygenation (OGD/R), including a decrease in cell viability and glutathione (GSH) levels and an increase in Fe2+ content. PDE4B knockdown mitigated the effects of OGD/R, as evidenced by decreased oxidative stress, lactate dehydrogenase (LDH) release, Fe2+ content, and nuclear receptor coactivator 4 (NCOA4) expression. PDE4B knockdown also enhanced the levels of GSH, ferroportin (FPN), and ferritin heavy chain 1 (FTH1). Consistently, inhibition of PDE4 by roflumilast (Roflu) produced similar effects as PDE4B knockdown. Roflu also ameliorated the morphology and membrane potential of the mitochondria. Glutathione peroxidase 4 (GPX4) knockdown blocked the effects of Roflu on cell viability and lipid peroxidation. Moreover, we found that nuclear factor erythroid 2-related factor 2 (Nrf-2) knockdown decreased GPX4 expression. In addition, Nrf-2 knockdown led to enhanced lipid peroxidation, LDH release, and iron levels, while the GSH and FPN levels decreased. More crucially, PDE4 inhibition decreased infarct volume, alleviated oxidative stress, and restored the expression levels of ferroptosis-associated proteins in middle cerebral artery occlusion/reperfusion (MCAO/R) rats. Interestingly, the GPX4 inhibitor RSL3 blocked the neuroprotective effects of Roflu in rats subjected to MCAO/R. Thus, PDE4 inhibition significantly inhibits neuronal ferroptosis by activating the Nrf-2/GPX4 pathway. These data indicate the existence of a novel mechanism underlying the neuroprotective effects of PDE4 inhibition.

Engineering hirudin encapsulation in pH-responsive antioxidant nanoparticles for therapeutic efficacy in ischemic stroke model mice

This study introduces a novel pH-sensitive, hirudin-loaded antioxidant nanoparticle (HD@iNanoAOX) aimed at addressing the challenges of hirudin's short half-life and hemorrhagic transformation. HD@iNanoAOX was engineered to safeguard and prolong hirudin's bioactivity by encapsulating it within antioxidative nanoparticles, facilitating its gradual release in acidic environments. The efficacy of this approach was validated through both ex vivo and in vivo experiments. Ex vivo thrombolytic assays demonstrated that HD@iNanoAOX maintained effective clot lysis activity under acidic conditions. In vivo assessments revealed that HD@iNanoAOX significantly prolonged hirudin's half-life and reduced cerebral infarct volume in a mouse model of middle cerebral artery occlusion (MCAO). Furthermore, HD@iNanoAOX treatment mitigated cerebral oxidative stress, suppressed hemorrhagic transformation, and prevented blood-brain barrier (BBB) disruption. These findings suggest that the combined thrombolytic and antioxidative properties of HD@iNanoAOX offer a promising therapeutic approach for ischemic stroke. Nonetheless, further research is warranted to optimize the formulation and assess its safety and efficacy in clinical settings.

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.

Sodium-Glucose Transporter-2 Inhibitors (SGLT2i) and Myocardial Ischemia: Another Compelling Reason to Consider These Agents Regardless of Diabetes

In recent years, the introduction of sodium-glucose transporter-2 inhibitors (SGLT2is) marked a significant advancement in the treatment of cardiovascular disease (CVD). Beyond their known effects on glycemic control and lipid profile, SGLT2is demonstrate notable benefits for cardiovascular morbidity and mortality, regardless of diabetic status. These agents are currently recommended as first-line therapies in patients with heart failure, both with reduced and preserved ejection fraction, as they improve symptoms and reduce the risk of hospitalization. While several studies have demonstrated that SGLT2is can reduce the incidence of major adverse cardiovascular events (MACEs), the true impact of these agents on atherosclerosis progression and myocardial ischemia remains to be fully understood. A global beneficial effect related to improved glycemic and lipid control could be hypothesized, even though substantial evidence shows a direct impact on molecular pathways that enhance endothelial function, exhibit anti-inflammatory properties, and provide myocardial protection. In this context, this narrative review summarizes the current knowledge regarding these novel anti-diabetic drugs in preventing and treating myocardial ischemia, aiming to define an additional area of application beyond glycemic control and heart failure.

The interactive toxic effect of homocysteine and copper on cardiac microvascular endothelial cells during ischemia-reperfusion injury

Hyperhomocysteinemia (HHcy) is associated with the development and progression of chronic cardiovascular diseases through the deleterious effects of high levels of homocysteine (Hcy) on the cardiovascular system. However, the exact mechanism of action of Hcy on the acute injury of the cardiovascular system following ischemia/reperfusion (I/R) remains unclear. The present study demonstrated that copper mobilization occurs during cardiac I/R, and the interactive toxic effect of Hcy and mobile Cu2+ during cardiac I/R induces necroptosis of cardiac microvascular endothelial cells (CMECs) and thus enhances cardiac dysfunction. In the present study, we utilized three cardiac I/R model: isolated rat heart, in vivo model as well as cell culture, and demonstrated that copper mobilization occurs during cardiac I/R, and the interactive toxic effect of Hcy and mobile Cu2+ during cardiac I/R induces necroptosis of cardiac microvascular endothelial cells (CMECs) and thus enhances cardiac dysfunction. Furthermore, we proved that the Cu2+ chelator TTM significantly mitigated the deleterious effects of Hcy and Cu2+ on CMECs and cardiac function both in vitro and in vivo. Mechanismly, the combinative effect of Hcy and Cu2+ are associated with the production of reactive oxygen species (ROS) and nitric oxide (NO) by NADPH oxidase (NOX) and endothelial nitric oxide synthase (eNOS), respectively. Subsequently, the overproduction of toxic peroxynitrite (ONOO-) induces CMECs necroptosis. The application of ROS scavengers in CMECs resulted in a notable reduction in necroptosis mediated by Hcy and Cu2+ under hypoxia/reperfusion (H/R) condition. These findings indicate that the mechanism by which Hcy and Cu2+ enhances cardiac dysfunction under I/R condition may be attributed to the stimulation of both NOX and eNOS activity, resulting in the generation of excessive ONOO- and subsequent necroptosis of CMECs.

Caveolin and oxidative stress in cardiac pathology

Caveolins interact with signaling molecules within caveolae and subcellular membranes. Dysregulation of caveolin function and protein abundance contributes to cardiac pathophysiological processes, driving the development and progression of heart disease. Reactive oxygen species (ROS) play a critical role in maintaining cellular homeostasis and are key contributors to the pathophysiological mechanisms of cardiovascular disorders. Caveolins have been shown to modulate oxidative stress and regulate redox homeostasis. However, the specific roles of caveolins, particularly caveolin-1 and caveolin-3, in regulating ROS production during cardiac pathology remain unclear. This mini-review article highlights the correlation between caveolins and oxidative stress in maintaining cardiovascular health and modulating cardiac diseases, specifically in myocardial ischemia, heart failure, diabetes-induced metabolic cardiomyopathy, and septic cardiomyopathy. A deeper understanding of caveolin-mediated mechanisms may pave the way for innovative therapeutic approaches to treat cardiovascular diseases.

Protective Effects of Bromelain in Testicular Torsion-Detorsion: Reducing Inflammation, Oxidative Stress, and Apoptosis While Enhancing Sperm Quality

Inflammation and increased oxidative stress in testicular tissue are documented side effects of torsion of the testicles. The preventive role of Bromelain (Bro) against testicle torsion-induced ischemia/reperfusion (I/R) injury was investigated in this research. Five groups of six animals each were created: ischemia, Ischemia+Reperfusion (I+R), Ischemia+Reperfusion+Bromelain (I+R+Bro; 10 mg/kg), control (sham), and Bromelain (Bro; 10 mg/kg). An I/R damage resulted from two hours of 720° clockwise twisting of the left testis. Blood samples and epididymal sperm were collected after reperfusion to analyze sperm parameters (recovery, motility, viability, and morphology) and cytokines that promote inflammation (IL-1β, IL-6, and TNF-α). Using Western blotting, testicular tissue was examined for histopathological alterations, antioxidant enzymes (GSH, SOD), lipid peroxidation (MDA), apoptosis, and survival-related proteins (TLR4, Caspase-3, Bcl-2, NRF-2, HO-1, PI3K, mTOR, AKT-1). While raising the activities of GSH and SOD, two antioxidant enzymes, Bro administration dramatically reduced MDA concentrations. The I+R+Bro group had significantly reduced amounts of cytokines that promoted inflammation compared to the I+R group. Bro's protective properties are also attributed to proteins that are altered by it and participate in the apoptosis and survival of cells. Sperm morphology, motility, and concentration notably improved in the bromelain-treated group, according to spermatological examination. Testicular samples treated with bromelain showed less tissue damage according to histological evaluations than the untreated I+R group. These findings imply that Bro has anti-inflammatory, anti-apoptotic, and antioxidant qualities. It effectively reduces oxidative stress and inflammation by modulating the PI3K/Akt/mTOR and NRF-2/HO-1 pathways, hence minimizing I/R injury.

A non-purine inhibitor of xanthine oxidoreductase mitigates adenosine triphosphate degradation under hypoxic conditions in mouse brain

The brain is an organ that consumes a substantial amount of oxygen, and a reduction in oxygen concentration can rapidly lead to significant and irreversible brain injury. The progression of brain injury during hypoxia involves the depletion of intracellular adenosine triphosphate (ATP) due to decreased oxidative phosphorylation in the inner mitochondrial membrane. Allopurinol is a purine analog inhibitor of xanthine oxidoreductase that protects against hypoxic/ischemic brain injury; however, its underlying mechanism of action remains unclear. In addition, febuxostat is a non-purine xanthine oxidoreductase inhibitor with a different inhibitory mechanism from allopurinol. The impact of febuxostat on brain injury has not been well investigated. Therefore, this study aimed to examine brain ATP and its catabolite levels in the presence or absence of allopurinol and febuxostat under hypoxic conditions by inactivating brain metabolism using focal microwave irradiation. The hypoxic treatment caused a decrease in the adenylate energy charge and ATP levels and an increase in its catabolic products in mouse brains. The febuxostat group showed higher energy charge and ATP levels and lower ATP catabolites than the control group. Notably, despite the comparable suppression of uric acid production in both inhibitor groups, allopurinol treatment was less effective than febuxostat. These results suggest that febuxostat effectively prevents hypoxia-induced ATP degradation in the brain and that its effect is more potent than allopurinol. This study will contribute to developing therapies for improving hypoxia-induced brain dysfunction.

Dexmedetomidine ameliorates hepatic ischemia reperfusion injury via modulating SIRT3 mediated mitochondrial quality control

Ischaemia-reperfusion (IR) damage is an inevitable adverse effect of liver surgery. Recent research has found that IR damage is involved in severe mitochondrial dysfunction. Mitochondrial biosynthesis and dynamics control mitochondrial mass, distribution, and function. Sirtuin 3 (SIRT3) is widely known for preserving health and functionality of mitochondria. DEX has been proven to alleviate liver damage through antioxidant and anti-apoptotic pathways. But it's unclear how DEX protects mitochondria at this time. In this research, the mechanism behind the protective benefits of DEX was examined using the rat liver IR model and the rat liver cells (BRL-3 A) hypoxia reoxygenation (HR) model. We discovered that DEX treatment restored mitochondrial membrane potential, promoted ATP production, prevented oxidative stress, and decreased apoptosis in BRL-3 A cells. Furthermore, HR damage increased mitochondrial fission while decreasing mitochondrial fusion and biogenesis in BRL-3 A cells, which DEX partially corrected. The benefits of DEX on mitochondrial protection were reversed after addition of SR-18,292. Additionally, DEX showed the ability to enhance SIRT3 expression, and after cells were transfected with SIRT3 siRNA, DEX's effects on mitochondria were partially prevented. Similarly, in the rat model, DEX alleviating liver histopathological injury and oxidative stress. DEX inhibited IR-induced mitochondrial damage through improving ETC complex I- IV activities and ATP content, reducing apoptosis, controlling mitochondrial quality, and upregulating the expression of SIRT3. Additionally, our research shows that DEX's ability to protect the liver against IR damage is mediated by the modulation of mitochondrial quality control. Overall, the modification of SIRT3 activity could be responsible for this outcome.

6'-O-caffeoylarbutin of Vaccinium dunalianum alleviated ischemic stroke through the PI3K/AKT/NF-κB pathway

BACKGROUND

Vaccinium dunalianum ("Que Zui Tea") has been traditionally consumed as a tea substitute in Yunnan, China, for its health benefits, i.e., improving vascular health. 6'-O-caffeoylarbutin (CA) is its major bioactive compound (∼20 %). However, the potential of CA against ischemic stroke remains unknown.

PURPOSE

This study explores the protective properties of CA in ischemic stroke, providing empirical support for the folk use of the plant and further drug development.

METHODS

An oxygen-glucose deprivation/reoxygenation (OGD/R)-induced BV2 cells were utilized to identify potential bioactive compounds. Moreover, the pathway and targets were predicted and further verified in OGD/R-induced microglia, nerve cells and in mice of middle cerebral artery occlusion.

RESULTS

CA effectively reduced nitric oxide (NO) release and transcript-level expression of inflammatory factors in OGD/R-stimulated BV2 cells. NF-κB1, IL-6, AKT1, CASP3, and MMP9 were identified as key CA targets for ischemic stroke treatment. In silico predictions suggested that phosphatidylinositol 3-kinase (PI3K)/protein kinase B (PI3K/AKT), mitogen-activated protein kinase (MAPK), and tumor necrosis factor (TNF) were the relevant pathways. These predictions were supported in vitro by an observed decrease in NO, reactive oxygen species, lactate dehydrogenase, and inflammatory cytokines (IL-6, IL-1β, and TNF-α) levels following CA treatment. Western blotting confirmed the regulation of p-IκBα, P65, AKT, and apoptosis-related proteins (further confirmed by PI3K inhibitor LY294002 treatment). These findings were further supported in vivo, with CA ameliorating neurological functions and deficits in ischemic mice. This amelioration correlated with increased cerebral blood flow, and alleviated neuron wrinkling, necrosis, and cell shrinkage. CA also increased brain superoxide dismutase, catalase, and glutathione peroxidase levels.

CONCLUSION

CA exerts neuroprotective effects in ischemic stroke by inhibiting inflammation and oxidative stress through the PI3K/AKT/NF-κB pathway, suggesting its therapeutic potential for cerebral ischemia and supporting the traditional use of V. dunalianum.

Effects of Microplastic Accumulation on Neuronal Death After Global Cerebral Ischemia

Brain ischemia, a condition in which the brain is deprived of blood flow, can lead to a stroke due to blocked or unstable blood vessels. Global cerebral ischemia (GCI), characterized by an interruption in blood flow, deprives the brain of oxygen and nutrients, producing reactive oxygen species (ROS) that trigger cell death, which kills nerve cells. Microplastics (MPs), tiny environmental pollutants, can enter the human body through contaminated food, water, disposable items, cosmetics, and more. Once in the brain, MPs can increase neuroinflammation by overstimulating inflammatory factors such as microglia. MPs can also damage neurons by scratching myelin and microtubules, slowing signal transduction, causing cognitive impairment, and leading to neuronal death. Furthermore, microtubule damage may result in the release of phosphorylated tau proteins, potentially linked to Alzheimer's disease. We hypothesized that MPs could exacerbate neuroinflammation and microtubule destruction after GCI, leading to increased neuronal death. To test this hypothesis, we administered MPs (0.5 µm) orally at a dose of 50 mg/kg before and after inducing GCI. Staining techniques such as Fluoro-Jade B (FJB), ionized calcium-binding adaptor molecule 1 (Iba-1), cluster of differentiation 68 (CD68), myelin basic protein (MBP), and microtubule-associated protein 2 (MAP2) were used, along with Western blot analysis for interleukin-6 (IL-6), TNF-α, tau-5, and phospho-tau (S396) to evaluate the effects of MPs on neuronal cell death, neuroinflammation, and microtubule destruction. The results showed that MP accumulation significantly increased neuroinflammation, microtubule disruption, and neuronal cell death in the GCI-MP group compared to the GCI-vehicle group. Therefore, this study suggests that MP accumulation in daily life may contribute to the exacerbation of the disease, potentially leading to severe neuronal cell death after GCI.

Selective nitric oxide redistribution by phospholipid nanoparticles: A novel strategy to mitigate massive nitric oxide release and prevent reperfusion injury in septic shock

Nitric oxide plays a critical role in regulating vascular tone, but excessive nitric oxide release during septic shock results in hypotension due to excessive vasodilation and the formation of toxic free radicals. VBI-S is a phospholipid nanoparticle based fluid composed of lipid bilayers formed primarily by phosphatidylcholine and micelles of soybean oil encapsulated by a monolayer of phosphatidylcholine. These nanoparticles offer a novel solution by absorbing and redistributing nitric oxide and nitrite, potentially mitigating the harmful effects of excessive nitric oxide in sepsis. This paper proposes a mechanism in which VBI-S not only redistributes nitric oxide but also reduces ischemia-reperfusion injury by limiting the production and availability of reactive species. VBI-S captures nitric oxide and nitrite in areas of high concentration and redistributes them in low-nitric oxide environments, primarily within oxygen-deprived tissues. Nitrite then contributes to nitric oxide regeneration in hypoxic microvasculature via various reduction pathways, thereby improving tissue perfusion and minimizing oxidative stress. Preliminary studies suggest that nitrite may also decrease reactive species production, primarily superoxide, through the inhibition of mitochondrial complex I. Additionally, the lipid composition of VBI-S is rich in poly and monounsaturated fatty acids which allows VBI-S to act as a substrate for peroxidation via peroxynitrite. Therefore, VBI-S acts as a decoy target thereby protecting cellular membranes from oxidative damage caused by reactive species. These findings position VBI-S as a promising therapeutic agent, offering both nitric oxide regulation and protection against hypotension and toxic free radicals in septic shock patients. Further research is necessary to fully elucidate the molecular pathways and optimize its clinical application.

Novel ruthenium(II) complex-based two-photon luminescent probe for visualizing biothiols in ferroptosis-mediated hepatic ischemia-reperfusion injury

Ferroptosis exhibits a critical role in the occurrence and progression of hepatic ischemia-reperfusion injury (HIRI), which is closely linked to the down regulation of biothiols. Visualization of biothiols in ferroptosis is of great significance for elucidating the pathological mechanism of HIRI as well as developing new clinical treatment strategies. However, reliable tools for monitoring biothiols and demonstrating their dynamic changes in ferroptosis-mediated HIRI are still lacking. Herein, this work developed an innovative Ru(II) complex-based two-photon luminescent probe, named Ru-PDBS, for accurate tracking the biothiols fluxes in ferroptosis-mediated HIRI. The newly developed probe possessed high sensitivity, good selectivity and favorable biocompatibility, which makes it to be used for imaging and dynamic monitoring of biothiols in living cells during ferroptosis-mediated HIRI. Furthermore, visualization of biothiols in mouse livers during ferroptosis-mediated HIRI and drug treatment was achieved for the first time. All these results suggested that Ru-PDBS can serve as a reliable tool for elucidating the pathogenesis of ferroptosis-mediated HIRI, as well as for developing of new therapies.

The interplay of NAD and hypoxic stress and its relevance for ageing

Nicotinamide adenine dinucleotide (NAD) is an essential regulator of cellular metabolism and redox processes. NAD levels and the dynamics of NAD metabolism change with increasing age but can be modulated via the diet or medication. Because NAD metabolism is complex and its regulation still insufficiently understood, achieving specific outcomes without perturbing delicate balances through targeted pharmacological interventions remains challenging. NAD metabolism is also highly sensitive to environmental conditions and can be influenced behaviorally, e.g., by exercise. Changes in oxygen availability directly and indirectly affect NAD levels and may result from exposure to ambient hypoxia, increased oxygen demand during exercise, ageing or disease. Cellular responses to hypoxic stress involve rapid alterations in NAD metabolism and depend on many factors, including age, glucose status, the dose of the hypoxic stress and occurrence of reoxygenation phases, and exhibit complex time-courses. Here we summarize the known determinants of NAD-regulation by hypoxia and evaluate the role of NAD in hypoxic stress. We define the specific NAD responses to hypoxia and identify a great potential of the modulation of NAD metabolism regarding hypoxic injuries. In conclusion, NAD metabolism and cellular hypoxia responses are strongly intertwined and together mediate protective processes against hypoxic insults. Their interactions likely contribute to age-related changes and vulnerabilities. Targeting NAD homeostasis presents a promising avenue to prevent/treat hypoxic insults and - conversely - controlled hypoxia is a potential tool to regulate NAD homeostasis.

In renal proximal tubular epithelial cells of the hibernator Syrian hamster, anoxia-reoxygenation-induced reactive oxygen species bursts do not trigger a DNA damage response and cellular senescence

Ischemia-reperfusion (I-R) injury represents a predominant etiology of acute kidney injury (AKI), for which effective treatments remain unavailable. In contrast, hibernating mammals exhibit notable resistance to cell death induced by I-R injury. However, the impact of I-R injury on cellular senescence-an important factor in AKI-has not been extensively studied in these species. Comparative biology may offer novel therapeutic insights. Renal proximal tubular epithelial cells (RPTECs) from the native hibernator Syrian hamster or mouse RPTECs were subjected to anoxia-reoxygenation. Proteins involved in DNA damage response (DDR) and cellular senescence were assessed using western blotting, reactive oxygen species (ROS) levels and cell death were quantified colorimetrically, and IL-6 with ELISA. Anoxia-reoxygenation induced oxidative stress in both mouse and hamster RPTECs; however, cell death was observed exclusively in mouse cells. While anoxia-reoxygenation elicited a DDR and subsequent senescence in mouse RPTECs, such responses were not detected in hamster RPTECs. Thus, RPTECs from the Syrian hamster exhibited increased ROS production upon reoxygenation but did not show DDR or cellular senescence. Further research is required to elucidate the specific protective molecular mechanisms in hibernators, which could potentially lead to the development of novel therapeutic approaches for I-R injury in non-hibernating species, including humans.

Assembly of Genetically Engineered Ionizable Protein Nanocage-based Nanozymes for Intracellular Superoxide Scavenging

Nanozymes play a pivotal role in mitigating excessive oxidative stress, however, determining their specific enzyme-mimicking activities for intracellular free radical scavenging is challenging due to endo-lysosomal entrapment. In this study, we employ a genetic engineering strategy to generate ionizable ferritin nanocages (iFTn), enabling their escape from endo-lysosomes and entry into the cytoplasm. Specifically, ionizable repeated Histidine-Histidine-Glutamic acid (9H2E) sequences are genetically incorporated into the outer surface of human heavy chain FTn, followed by the assembly of various chain-like nanostructures via a two-armed polyethylene glycol (PEG). Utilizing endosome-escaping ability, we design iFTn-based tetrameric cascade nanozymes with high superoxide dismutase- and catalase-mimicking activities. The in vivo protective effects of these ionizable cascade nanozymes against cardiac oxidative injury are demonstrated in female mouse models of cardiac ischemia-reperfusion (IR). RNA-sequencing analysis highlight the crucial role of these nanozymes in modulating superoxide anions-, hydrogen peroxide- and mitochondrial functions-relevant genes in IR injured cardiac tissue. These genetically engineered ionizable protein nanocarriers provide opportunities for developing ionizable drug delivery systems.

Exploring the Molecular Interplay Between Oxygen Transport, Cellular Oxygen Sensing, and Mitochondrial Respiration

Significance: The mitochondria play a key role in maintaining oxygen homeostasis under normal oxygen tension (normoxia) and during oxygen deprivation (hypoxia). This is a critical balancing act between the oxygen content of the blood, the tissue oxygen sensing mechanisms, and the mitochondria, which ultimately consume most oxygen for energy production. Recent Advances: We describe the well-defined role of the mitochondria in oxygen metabolism with a special focus on the impact on blood physiology and pathophysiology. Critical Issues: Fundamental questions remain regarding the impact of mitochondrial responses to changes in overall blood oxygen content under normoxic and hypoxic states and in the case of impaired oxygen sensing in various cardiovascular and pulmonary complications including blood disorders involving hemolysis and hemoglobin toxicity, ischemia reperfusion, and even in COVID-19 disease. Future Directions: Understanding the nature of the crosstalk among normal homeostatic pathways, oxygen carrying by hemoglobin, utilization of oxygen by the mitochondrial respiratory chain machinery, and oxygen sensing by hypoxia-inducible factor proteins, may provide a target for future therapeutic interventions. Antioxid. Redox Signal. 00, 000-000.

Outcome and Predisposing Factors for Intracranial Hemorrhage in Turkish Children with Hemophilia

Background/Objectives: Childhood hemophilia, a hereditary bleeding disorder predominantly affecting males, arises due to gene mutations encoding clotting factors VIII or IX. Intracranial hemorrhage represents a significant and life-threatening complication in pediatric patients with hemophilia. The incidence of intracranial hemorrhage in children with hemophilia, although relatively low, is notably higher compared to the general pediatric population. Methods: In this study, the objective is to examine patients with hemophilia who have experienced intracranial hemorrhage retrospectively. This study is a multicenter, retrospective analysis using data from three tertiary care centers in a provincial city in Turkey. Data were obtained from the participants' hospital records. The presence of inhibitors against FVIII in the participants and the prophylaxis used against them were included in the analysis. Trauma history was queried, with types of traumas examined, including traffic accidents, falls, and a traumatic vaginal delivery. The duration and causes of complaints among the participants were investigated. The causes of complaints were categorized as fever, hematoma, convulsions, loss of consciousness, and hemiparesis. The participants' Physical Examination Findings were classified as fever, hematoma, and loss of consciousness. The duration of hospital stays was evaluated. The hemorrhage location was classified into five groups: parenchymal, subdural, scalp, subarachnoid, and multiple hemorrhagic foci. The recurrence of bleeding, the need for transfusion, surgical intervention, and mortality were also examined. Results: A significant difference was identified between the participants' survival rates and age variables, as well as transfusion in <36 months. A total of 9 participants had spontaneous intracranial bleeding, 2 experienced cranial trauma as a result of traffic accidents, and 25 participants were exposed to head trauma due to falls. Of the remaining individuals, one suffered head trauma from a severe impact, and one had cranial trauma following a traumatic vaginal delivery. Fourteen participants required transfusion, and three underwent surgical intervention. Conclusions: According to the results of the statistical analyses, the variables Factor Level, Physical Examination Findings, Transfusion, Recurrent Bleeding, Inhibitor, and Prophylaxis were found to affect survival significantly. No significant relationship was determined between the other analyzed variables and survival. During our study, five of the participants examined died. Accordingly, the mortality rate identified in our study is 13.1%.

Dysregulation of Mitochondrial Homeostasis in Cardiovascular Diseases

Mitochondria dysfunction plays a central role in the development of vascular diseases as oxidative stress promotes alterations in mitochondrial morphology and function that contribute to disease progression. Redox imbalances can affect normal cellular processes including mitochondrial biogenesis, electrochemical equilibrium, and the regulation of mitochondrial DNA. In this review, we will discuss these imbalances and, in particular, the potential role of mitochondrial fusion, fission, biogenesis, and mitophagy in the context of vascular diseases and how the dysregulation of normal function might contribute to disease progression. We will also discuss potential implications of targeting mitochondrial regulation as therapeutic targets to treat vascular disease formation.

Restoration effect of chemically modified microRNA-143-3p on acute myocardial infarction in animal models

We investigated whether miR143#12, a synthesized chemically modified miR-143-3p derivative, exerts therapeutic effects on acute myocardial infarction (AMI). Sprague-Dawley rats and Japanese white rabbits underwent 30 min of coronary occlusion followed by 2 weeks of reperfusion. The rat AMI model was intravenously administered with control miRNA (9 μg/kg), 3 μg/kg or 9 μg/kg of miR143#12 1 h after reperfusion, while the rabbit AMI model was intravenously administered with control miRNA (9 μg/kg) or 9 μg/kg of miR143#12. In the rat and rabbit AMI models, 9 μg/kg of miR143#12 significantly reduced infarct sizes and significantly improved cardiac function including LVEF and LVFS at 2 weeks. The tissue miR143 levels in infarct areas significantly decreased after AMI in both models. Electron microscopic study and immunohistochemistry suggested that miR143#12 suppressed autophagic cell death caused by AMI and induced neoangiogenesis in the infarct border. In cultured rat H9c2 cells, miR143#12 significantly inhibited H2O2-induced autophagic cell death by decreasing ROS levels and increased viable cell numbers more than the control by silencing COX-1, -2, and ATG7. Replacement treatment with miR143#12 in the infarct areas, where the expression levels of miR143 were significantly decreased, has a beneficial effect on AMI by silencing COX-1 and -2.

Mechanisms of postischemic cardiac death and protection following myocardial injury

Acute myocardial infarction (MI) is a leading cause of death worldwide. Although with current treatment, acute mortality from MI is low, the damage and remodeling associated with MI are responsible for subsequent heart failure. Reducing cell death associated with acute MI would decrease the mortality associated with heart failure. Despite considerable study, the precise mechanism by which ischemia and reperfusion (I/R) trigger cell death is still not fully understood. In this Review, we summarize the changes that occur during I/R injury, with emphasis on those that might initiate cell death, such as calcium overload and oxidative stress. We review cell-death pathways and pathway crosstalk and discuss cardioprotective approaches in order to provide insight into mechanisms that could be targeted with therapeutic interventions. Finally, we review cardioprotective clinical trials, with a focus on possible reasons why they were not successful. Cardioprotection has largely focused on inhibiting a single cell-death pathway or one death-trigger mechanism (calcium or ROS). In treatment of other diseases, such as cancer, the benefit of targeting multiple pathways with a "drug cocktail" approach has been demonstrated. Given the crosstalk between cell-death pathways, targeting multiple cardiac death mechanisms should be considered.

The Effect of Dapagliflozin on Heart Function in Animal Models of Cardiac Ischemia, A Systematic Review and Meta-analysis

INTRODUCTION

In this study, a meta-analysis was conducted to investigate the therapeutic effect of Dapagliflozin (DAPA) on animals suffering from myocardial ischemia reperfusion compared to the group that did not receive treatment.

METHODS

According to the inclusion and exclusion criteria two researchers performed the primary and secondary screening based on the title abstract and full text. After data extraction, meta-analysis was performed using STATA software. Standardized mean differences were used to analyze the results of the reported studies. Subgroup analysis and quality control of articles were also conducted.

RESULTS

A total of 21 separate experiments showed that DAPA increased mean fractional shortening (%FS) and ejection fraction (%EF) compared to the untreated animals. A significant reduction in the weight and size of the infarcted area and significant increases in dp/dt+, dp/dt-, left ventricular end-systolic internal dimensions (LVIDs), left ventricular end-diastolic internal dimensions (LVIDd), Volume systole and Volume diastole were observed in treated animals.

CONCLUSION

DAPA has the potential to become a candidate for the treatment of post-ischemic heart damage, pending animal and human studies to validate this.

Mitochondrial Uncoupling Protein-2 Ameliorates Ischemic Stroke by Inhibiting Ferroptosis-Induced Brain Injury and Neuroinflammation

Ischemic stroke is a devastating disease in which mitochondrial damage or dysfunction substantially contributes to brain injury. Mitochondrial uncoupling protein-2 (UCP2) is a member of the UCP family, which regulates production of mitochondrial superoxide anion. UCP2 is reported to be neuroprotective for ischemic stroke-induced brain injury. However, the molecular mechanisms of UCP2 in ischemic stroke remain incompletely understood. In this study, we investigated whether and how UCP2 modulates neuroinflammation and regulates neuronal ferroptosis following ischemic stroke in vitro and in vivo. Wild-type (WT) and UCP2 knockout (Ucp2-/-) mice were subjected to middle cerebral artery occlusion (MCAO). BV2 cells (mouse microglial cell line) and HT-22 cells (mouse hippocampal neuronal cell line) were transfected with small interfering (si)-RNA or overexpression plasmids to knockdown or overexpress UCP2 levels. Cells were then exposed to oxygen-glucose deprivation and reoxygenation (OGD/RX) to simulate hypoxic injury in vitro. We found that UCP2 expression was markedly reduced in a time-dependent manner in both in vitro and in vivo ischemic stroke models. In addition, UCP2 was mainly expressed in neurons. UCP2 deficiency significantly enlarged infarct volumes, aggravated neurological deficit scores, and exacerbated cerebral edema in mice after MCAO. In vitro knockdown of Ucp2 and in vivo genetic depletion of Ucp2 (Ucp2-/- mice) increased neuronal ferroptosis-related indicators, including Fe2+, malondialdehyde, glutathione, and lipid peroxidation. Overexpression of UCP2 in neuronal cells resulted in reduced ferroptosis. Moreover, knockdown of UCP2 exacerbated neuroinflammation in BV2 microglia and mouse ischemic stroke models, suggesting that endogenous UCP2 inhibits neuroinflammation following ischemic stroke. Upregulation of UCP2 expression in microglia appeared to decrease the release of pro-inflammatory factors and increase the levels of anti-inflammatory factors. Further investigation showed that UCP2 deletion inhibited expression of AMPKα/NRF1 pathway-related proteins, including p-AMPKα, t-AMPKα, NRF1, and TFAM. Thus, UCP2 protects the brain from ischemia-induced ferroptosis by activating AMPKα/NRF1 signaling. Activation of UCP2 represents an attractive strategy for the prevention and treatment of ischemic stroke.

BAK ameliorated cerebral infarction/ischemia-reperfusion injury by activating AMPK/Nrf2 to inhibit TXNIP/NLRP3/caspase-1 axis

BACKGROUND

Cerebral ischemia/reperfusion (I/R) injury is a serious vascular disease with extremely high mortality and disability rate. Bakuchiol (BAK) was found in leaves and seeds of Psoralea corylifolia Linn and has been shown to decrease inflammation and reduce oxidative stress, while the mechanism of BAK in ameliorating cerebral I/R injury remains unclear.

METHODS

Middle cerebral artery occlusion reperfusion (MACO/R) was used to establish mouse model. The protective effect of BAK in MCAO/R mices was detected by performing neurological deficit testing, TTC staining, and H&E staining. Oxygen/glucose deprivation and reperfusion (OGD/R) was used to stimulate SH-SY5Y cells in vitro. Protein expression was detected by western blotting, gene expression was detected by quantitative real-time polymerase chain reaction and apoptosis was detected by immunofluorescence.

RESULTS

Our study indicated that BAK protected ischemia-reperfusion injury in MACO/R mice, and upregulated superoxide dismutase (SOD) and the catalase (CAT) enzyme activity. BAK also inhibited the expression of TNF-α, IL-1β, IL-6, and IL-18 and suppressed apoptosis and pyroptosis both in MACO/R mice and in OGD/R SH-SY5Y cells. Further results showed that BAK could suppress TXNIP, ASC, NLRP3, and caspase-1 mRNA levels to reverse assembly of inflammasome. And BAK could also upregulate the expression of phosphorylated AMP-activated protein kinase (AMPK) and nuclear factor erythroid 2-related factor (Nrf2). In addition, Nrf2 inhibitor ML385 reversed the BAK induced reduction of TXNIP, ASC, NLRP3, and the AMPK inhibitor also abolished BAK' the effect on the regulation of Nrf2, TXNIP, ASC, NLRP3, caspase-1, and pro-inflammatory cytokines. In conclusion, BAK, found in leaves and seeds of Psoralea corylifolia Linn, could ameliorated cerebral I/R injury through activating AMPK/Nrf2 to inhibit NLRP3 inflammasome, which might present new therapeutic strategy for cerebral I/R injury.

Modulation of Angiotensin-II and Angiotensin 1-7 Levels Influences Cardiac Function in Myocardial Ischemia-reperfusion Injury

The angiotensin-converting enzyme-2 (ACE-2) alters the pathophysiology of various fatal cardiovascular diseases, including ischemic heart disease, whereas angiotensin 1-7 (Ang 1-7) exerts a wide range of actions. The effects of ischemia-reperfusion (IR) injury include damage to myocardial tissue that initiates protease action, causing cardiac cell death. Angiotensin- II (Ang-II) contributes through the renin-angiotensin system (RAS) to the IR injury, whereas Ang 1-7 paradoxically exerts a protective effect through the same. Thus, the myocardial ischemic reperfusion injury (MIRI) may be altered by the RAS of the heart. This review paper focuses on ACE-2, angiotensin-converting enzyme (ACE), and Ang 1-7 regulation in the RAS of the heart in the pathophysiology of MIRI. The treatment in such conditions using ACE-2 activator, ACE inhibitor, and Ang-II antagonists may promote vascular functions as well as cardio- protection.

Intestinal oxygen utilisation and cellular adaptation during intestinal ischaemia-reperfusion injury

The gastrointestinal tract can be deranged by ailments including sepsis, trauma and haemorrhage. Ischaemic injury provokes a common constellation of microscopic and macroscopic changes that, together with the paradoxical exacerbation of cellular dysfunction and death following restoration of blood flow, are collectively known as ischaemia-reperfusion injury (IRI). Although much of the gastrointestinal tract is normally hypoxemic, intestinal IRI results when there is inadequate oxygen availability due to poor supply (pathological hypoxia) or abnormal tissue oxygen use and metabolism (dysoxia). Intestinal oxygen uptake usually remains constant over a wide range of blood flows and pressures, with cellular function being substantively compromised when ischaemia leads to a >50% decline in intestinal oxygen consumption. Restoration of perfusion and oxygenation provokes additional injury, resulting in mucosal damage and disruption of intestinal barrier function. The primary cellular mechanism for sensing hypoxia and for activating a cascade of cellular responses to mitigate the injury is a family of heterodimer proteins called hypoxia-inducible factors (HIFs). The HIF system is connected to numerous biochemical and immunologic pathways induced by IRI and the concentration of those proteins increases during hypoxia and dysoxia. Activation of the HIF system leads to augmented transcription of specific genes in various types of affected cells, but may also augment apoptotic and inflammatory processes, thus aggravating gut injury. KEY POINTS: During intestinal ischaemia, mitochondrial oxygen uptake is reduced when cellular oxygen partial pressure decreases to below the threshold required to maintain normal oxidative metabolism. Upon reperfusion, intestinal hypoxia may persist because microcirculatory flow remains impaired and/or because available oxygen is consumed by enzymes, intestinal cells and neutrophils.

Gastrodin: Modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways to inhibit ferroptosis after ischemic stroke

Ischemic stroke ranks as the second leading cause of global mortality and disability. Although reperfusion is crucial for salvaging brain tissue, it carries the risk of secondary injuries, such as ferroptosis. Gastrodin, a neuroprotective compound found in Chinese herbal medicine, may regulate this process. However, its impact on stroke-induced ferroptosis remains unclear.

OBJECTIVE

This research endeavors to probe Gastrodin's influence on post-ischemic ferroptosis, deciphering its mechanisms and assessing its therapeutic promise.

METHODS

We developed rat models of middle cerebral artery occlusion/reperfusion (MCAO/R) and created oxygen-glucose deprivation/reoxygenation (OGD/R)-damaged PC12 cell models. Gastrodin was administered to assess ferroptosis using Prussian blue staining and fluorescence probes. To investigate the effects of gastrodin on the xCT/GPX4 and ACSL4/LPCAT3 pathways, we employed molecular docking, immunofluorescence, Western blotting, and quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, we used transmission electron microscopy and JC-1 fluorescence probes to examine mitochondrial integrity and function.

RESULTS

Our study demonstrated that gastrodin significantly reduced iron accumulation and lipid peroxidation in the brains of MCAO/R rats and OGD/R-injured PC12 cells. It suppressed reactive oxygen species (ROS) and ameliorated mitochondrial membrane potential. It potentiates the xCT/GPX4 axis while repressing the ACSL4/LPCAT3 pathway, leading to improved mitochondrial architecture and function, notably characterized by decreased mitochondrial membrane potential, reduced ROS levels, and increased formation of mitochondrial cristae. By modulating the xCT/GPX4 and ACSL4/LPCAT3 pathways, gastrodin mitigated ferroptosis in ischemic stroke, thereby preserving mitochondrial structural and functional integrity. This study provides novel mechanistic insights into gastrodin's therapeutic potential for treating ischemic stroke, highlighting the importance of traditional Chinese medicine in modern medical therapy.

Chronic kidney disease and aging: dissecting the p53/p21 pathway as a therapeutic target

Chronic kidney diseases (CKD) are a group of multi-factorial disorders that markedly impair kidney functions with progressive renal deterioration. Aging contributes to age-specific phenotypes in kidneys, which undergo several structural and functional alterations, such as a decline in regenerative capacity and increased fibrosis, inflammation, and tubular atrophy, all predisposing them to disease and increasing their susceptibility to injury while impeding their recovery. A central feature of these age-related processes is the activation of the p53/p21 pathway signaling. The pathway is a key player in cellular senescence, apoptosis, and cell cycle regulation, which are all key to maintaining the health of the kidney. P53 is a transcription factor and a tumor suppressor protein that responds to cell stress and damage. Persistent activation of cell p53 can lead to the expression of p21, an inhibitor of the cell cycle known as a cyclin-dependent kinase. This causes cells to cease dividing and leads to senescence, where cells can no longer increase. The accumulation of senescent cells in the aging kidney impairs kidney function by altering the microenvironment. As the number of senescent cells increases, the capacity of the kidney to recover from injury decreases, accelerating the progression of end-stage renal disease. This article review extensively explores the relationship between the p53/p21 pathway and cellular senescence within an aging kidney and the emerging therapeutic strategies that target it to overcome the impacts of cellular senescence on CKD.

Acetyl-11-keto-β-boswellia acid attenuates Ti particle-induced osteoblastic oxidative stress and osteolysis through the Foxo3 signaling pathway

Oxidative stress injury in osteoblasts is one of the leading causes of periprosthetic osteolysis (PPOL). Acetyl-11-keto-β-boswellia acid (AKBA) has been used as an antioxidant in the treatment of various diseases, but its antioxidant mechanism in osteolysis has yet to be elucidated. In this study, a mouse cranial osteolysis model was constructed, and MC3T3-E1 cells and bone marrow mesenchymal stem cells (BMSCs) were cultured in vitro. Western blotting and immunofluorescence staining revealed that titanium (Ti) particles aggravated osteoblast oxidative stress injury and apoptosis. Ti particles and hydrogen peroxide reduced the osteogenic ability of BMSCs. At a certain concentration, AKBA alleviated the oxidative stress injury of MC3T3-E1 cells induced by Ti particles and enhanced the osteogenic ability of BMSCs, and the expression of Forkhead box O3 (Foxo3) increased with increasing AKBA concentration. To verify the antioxidant mechanism of AKBA, we designed and synthesized Foxo3-targeting siRNAs. We found that after Foxo3 expression was inhibited, the protective effect of AKBA on osteoblasts decreased significantly. Moreover, AKBA treatment suppressed bone mass loss in the skull mediated by Ti particles in mice. Therefore, we suggest that AKBA alleviates the oxidative stress injury in osteoblasts induced by Ti particles, at least in part, by regulating the expression of Foxo3. In this study, the mechanism and biosafety of AKBA in treating PPOL were demonstrated to some extent.

Molecular mechanisms and potential targets of lycopene for alleviating renal ischemia-reperfusion injury revealed by network pharmacology and animal experiments

OBJECTIVE

Renal IRI is one of the leading causes of AKI. How to effectively mitigate renal IRI is important for the recovery of renal function. The regulatory mechanism of lycopene, a natural antioxidant, in renal IRI is currently unknown. Therefore, we utilized network pharmacology and animal experiments to explore the possible mechanisms and potential targets of lycopene for alleviating renal IRI.

METHODS

We obtained lycopene-regulated genes and renal IRI-related genes from the CTD database and GeneCards database, respectively. Subsequently, the two were intersected and the intersecting genes we defined as lycopene-regulated genes in renal IRI. Next, we explored their potential biological functions and mechanisms through enrichment analysis. Meanwhile, we constructed a rat renal IRI model and validated the protective effects of lycopene and related mechanisms. To further explore the Hub genes regulated by lycopene, we constructed a PPI protein interactions network and characterized the Hub genes using Cytoscape software. We also verified the expression of Hub genes using animal experiments and molecular docking techniques. Finally, we constructed TF-Hub gene and miRNA-Hub gene regulatory networks.

RESULTS

We obtained a total of 255 lycopene-regulated genes and 327 renal IRI-related genes. The enrichment analysis revealed that they were closely related to the regulation of oxidative stress as well as the regulation of inflammatory factors. At the same time, the MAPK signaling pathway was significantly enriched. Next, we found in animal experiments that lycopene significantly alleviated the level of oxidative stress and inflammation during renal IRI, and had a protective effect on kidney damage. Also, we found that this protective effect may be achieved by inhibiting the MAPK signaling pathway. Next, we identified a total of five Hub genes using Cytoscape software: TNF, AKT1, MAPK3, IL6 and CASP3. Both animal experiments and molecular docking techniques demonstrated that lycopene can effectively regulate the expression of Hub genes. Finally, our constructed TF-Hub gene and miRNA-Hub gene regulatory network provide a theoretical basis for further regulation of Hub genes in follow-up.

CONCLUSIONS

This study suggests that lycopene is a promising option in mitigating renal IRI. Lycopene may exert protective effects by inhibiting the MAPK signaling pathway.

Carthamus tinctorius L. protects cerebral ischemia/reperfusion injury via arachidonic acid/p53-mediated apoptosis axis

Introduction

Stroke is a debilitating disease and the second leading cause of death worldwide, of which ischemic stroke is the dominant type. Carthamus tinctorius L., also known as safflower, has been used to treat cerebrovascular diseases, especially ischemic stroke in many Asian countries. However, the underlying mechanisms of safflower in preventing ischemic stroke remains elusive. This study aims to elucidate the potential of safflower as a drug candidate for the prevention of ischemic stroke and to delineate its protective effects and potential mechanisms in a rat model of cerebral ischemia-reperfusion injury (CI/RI).

Methods

The aqueous extract of safflower (AESF) was verified using HPLC-UV, HPLC-MS, and TLC. The inhibitory effect of AESF on platelet aggregation was detected in vitro and in zebrafish and mice. A CI/RI model in rats was established by middle cerebral artery occlusion and reperfusion to study the protective effect of AESF on ischemic stroke. 2,3,5-triphenyltetrazolium chloride, hematoxylin and eosin, and Nissl's staining were employed to evaluate the pathological changes of brain tissue. In addition, metabolomics, ELISA, and Western blot were used to uncover the molecular alteration induced by AESF.

Results

AESF significantly inhibited platelet aggregation in vitro, reduced the thrombogenesis in zebrafish, and prolonged clotting time in mice. In addition, AESF alleviated neurological dysfunction, cerebral oedema, cerebral infarct size, cerebral histopathological damage induced by ischemia-reperfusion, improved neuronal survival, increased serum levels of SOD and CAT, and decreased levels of iNOS and NO. Metabolomics revealed that AESF attenuated the metabolic disturbances in brain caused by I/R injury via regulating 38 metabolites particularly related to the arachidonic acid (AA) metabolism. Moreover, AESF elevated the serum levels of 6-keto-PGF1α, a pivotal metabolite of AA, downregulated the protein expression of p53, Bax, cleaved caspase-9, cleaved caspase-3, and cleaved caspase-8, and upregulated that of Bcl-2.

Conclusion

AESF mitigated CI/RI through preventing platelet aggregation, alleviating oxidative stress, and suppressing apoptosis partially via modulating AA metabolism/p53-mediated apoptosis axis.