The role of reactive oxygen species in angiogenesis and preventing tissue injury after brain ischemia

Reduced ischemia-reperfusion oxidative stress injury by melatonin and N-acetylcysteine in the male rat brain

Middle cerebral artery occlusion (MCAO) is a model for inducing ischemic stroke in rodents, leading to devastating brain damage. Oxidative stress (OS) plays a crucial role in the pathogenesis of ischemia. In this study, the effect of melatonin and N-acetylcysteine on ischemia-reperfusion-induced oxidative stress injury in the cerebral cortex of male rats was investigated. 30 male Wistar rats were divided into sham, ischemic, NAC, melatonin and NAC + melatonin groups. All groups, except the sham group, underwent MCAO on the left side, and the treatment groups received intraperitoneal injections of either 50 mg/kg N-acetylcysteine (NAC) or 5 mg/kg melatonin or a combination of both 24 and 48 hours later. At 24 and 72 hours after surgery, the animals were examined for sensory and motor activity. The cerebral cortex was dissected after sacrificing the rats, infarct volume estimated and the concentrations of glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and nuclear factor erythroid-2 related factor 2 (Nrf2) were analyzed by enzyme-linked immunosorbent assay (ELISA). The results indicate that the NAC + melatonin group exhibited elevated sensory-motor activity and a reduced infarct volume rate in comparison to the ischemic group (p≤ 0.05). Compared to the ischemic group, the NAC + melatonin group showed a significant increase in SOD concentration and a significant decrease in MDA (p≤ 0.05). It can therefore be concluded that the simultaneous administration of NAC and melatonin can reduce the cerebral infarction volume, and improve neurological functions by modulating SOD and MDA.

Evolucollateral dynamics in stroke: Evolutionary pathophysiology, remodelling and emerging therapeutic strategies

Leptomeningeal collaterals (LMCs) are crucial in mitigating the impact of acute ischemic stroke (AIS) by providing alternate blood flow routes when primary arteries are obstructed. This article explores the evolutionary pathophysiology of LMCs, highlighting their critical function in stroke and the genetic and molecular mechanisms governing their development and remodelling. We address the translational challenges of applying animal model findings to human clinical scenarios, emphasizing the need for further research to validate emerging therapies-such as pharmacological agents, gene therapy and mechanical interventions-in clinical settings, aimed at enhancing collateral perfusion. Computational modelling emerges as a promising method for integrating experimental data, which requires precise parameterization and empirical validation. We introduce the 'Evolucollateral Dynamics' hypothesis, proposing a novel framework that incorporates evolutionary biology principles into therapeutic strategies, offering new perspectives on enhancing collateral circulation. This hypothesis emphasizes the role of genetic predispositions and environmental influences on collateral circulation, which may impact therapeutic strategies and optimize treatment outcomes. Future research must incorporate human clinical data to create robust treatment protocols, thereby maximizing the therapeutic potential of LMCs and improving outcomes for stroke patients.

The Potential Interplay Between HIF-1α, Angiogenic, and Autophagic Signaling During Intermittent Hypoxic Exposure and Exercise

Berkemeier, Quint N., Michael R. Deyhle, James J. McCormick, Kurt A. Escobar, and Christine M. Mermier. The potential interplay between HIF-1α, angiogenic, and autophagic signaling during intermittent hypoxic exposure and exercise High Alt Med Biol. 25:326-336, 2024.-Environmental hypoxia as a result of decreased barometric pressure upon ascent to high altitudes (>2,500 m) presents increased physiological demands compared with low altitudes, or normoxic environments. Competitive athletes, mountaineers, wildland firefighters, military personnel, miners, and outdoor enthusiasts commonly participate in, or are exposed to, forms of exercise or physical labor at moderate to high altitudes. However, the majority of research on intermittent hypoxic exposure is centered around hematological markers, and the skeletal muscle cellular responses to exercise in hypoxic environments remain largely unknown. Two processes that may be integral for the maintenance of cellular health in skeletal muscle include angiogenesis, or the formation of new blood vessels from preexisting vasculature and autophagy, a process that removes and recycles damaged and dysfunctional cellular material in the lysosome. The purpose of this review is to is to examine the current body of literature and highlight the potential interplay between low-oxygen-sensing pathways, angiogenesis, and autophagy during acute and prolonged intermittent hypoxic exposure in conjunction with exercise. The views expressed in this paper are those of the authors and do not reflect the official policy of the Department of Army, DOD, DOE, ORAU/ORISE or U.S. Government.

Cellular and molecular roles of reactive oxygen species in wound healing

Wound healing is a highly coordinated spatiotemporal sequence of events involving several cell types and tissues. The process of wound healing requires strict regulation, and its disruption can lead to the formation of chronic wounds, which can have a significant impact on an individual's health as well as on worldwide healthcare expenditure. One essential aspect within the cellular and molecular regulation of wound healing pathogenesis is that of reactive oxygen species (ROS) and oxidative stress. Wounding significantly elevates levels of ROS, and an array of various reactive species are involved in modulating the wound healing process, such as through antimicrobial activities and signal transduction. However, as in many pathologies, ROS play an antagonistic pleiotropic role in wound healing, and can be a pathogenic factor in the formation of chronic wounds. Whilst advances in targeting ROS and oxidative stress have led to the development of novel pre-clinical therapeutic methods, due to the complex nature of ROS in wound healing, gaps in knowledge remain concerning the specific cellular and molecular functions of ROS in wound healing. In this review, we highlight current knowledge of these functions, and discuss the potential future direction of new studies, and how these pathways may be targeted in future pre-clinical studies.

N-Aryl Benzimidazole and Benzotriazole Derivatives and Their Hybrids as Cytotoxic Agents: Design, Synthesis and Structure-Activity Relationship Studies

The era of chemotherapy began in the 1940s, which is the basis of traditional antitumor approaches and, being one of the most high-tech treatment methods, is still widely used to treat various types of cancer. A promising direction in modern medicinal chemistry is currently the creation of hybrid molecules containing several pharmacophore fragments of different structures. This strategy is successfully used to increase the therapeutic efficacy of cytotoxic agents and reduce side effects. In this work, we synthesized 10 1-aryl derivatives of benzimidazole and benzotriazole and 11 hybrids based on them. Among the compounds obtained, the most promising hybrid molecules were diphenylamines, containing an amino group and a benzotriazole cycle in the ortho position to the bridging NH group, which showed significant cytotoxic activity, excellent antioxidant properties and the ability to suppress the migration activity of tumor cells. Taken together, our results demonstrate that substituted diphenylamine-based bipharmacophoric compounds may serve as a promising platform for further optimization to obtain effective antitumor compounds.

Neuroprotective effects of Aframomum pruinosum seed extract against stroke in rat: Role of antioxidant and anti-inflammatory mechanisms

BACKGROUND

Stroke is a major cause of disability and neurological impairment worldwide. Effective prevention and management strategies are needed to reduce its burden. This study aimed to investigate the therapeutic effect of the seed ethanolic extract of Aframomum pruinosum (EEAP) on stroke and its related motor and cognitive deficits in rats.

MATERIALS AND METHODS

Stroke was induced by either middle cerebral artery occlusion (MCAO) or bilateral common carotid artery occlusion (BCCAO). In the MCAO model, rats received EEAP (75, 150, or 300 mg kg-1) or N-acetyl-L-cysteine (100 mg kg-1) orally for one week before 2 h of occlusion, followed by reperfusion. Twenty-four hours after ischemia, brain was collected for infarct size using 2, 3, 5 -TriphenylTetrazolium Chloride (TTC) staining, oxidative stress markers and inflammatory cytokines (TNF-α, IL-1β) measurements. In the BCCAO model, rats underwent occlusion for 30 min and received EEAP or quercetin (25 mg kg-1) for 7 days post-induction. Behavioral parameters were evaluated at the end of the treatment. Oxidative stress and inflammatory markers were measured in the cerebrum and cerebellum.

RESULTS

MCAO caused significant brain infarction, and increased lipid peroxidation, TNF-α and IL-1β contents. EEAP, rich in nerolidol, prevented these changes in a dose-dependent manner. BCCAO impaired the neurological function, mobility, and muscle strength of rats. It also increased lipid peroxidation and inflammatory cytokines in the cerebellum. EEAP significantly ameliorated these impairments.

CONCLUSION

EEAP exerts preventive and curative neuroprotective effects against ischemic stroke and its associated motor impairments at least partially through its antioxidant and anti-inflammatory properties, and its nerolidol content.

Electroacupuncture attenuates cerebral ischemia/reperfusion injury by regulating oxidative stress, neuronal death and neuroinflammation via stimulation of PPAR-γ

BACKGROUND

Oxidative stress and inflammatory responses play essential roles in cerebral ischemia/reperfusion (I/R) injury. Electroacupuncture (EA) is widely used as a rehabilitation method for stroke in China; however, the underlying mechanism of action remains unclear. Peroxisome proliferator-activated receptor gamma (PPAR-γ) has been reported to impact anti-inflammatory and anti-oxidative effects.

OBJECTIVE

This study investigated the role of PPAR-γ in EA-mediated effects and aimed to illuminate its possible mechanisms in cerebral I/R.

METHODS

In this study, male Sprague-Dawley (SD) rats with middle cerebral artery occlusion/reperfusion (MCAO/R) injury were treated with EA at LI11 and ST36 for 30 min daily after MCAO/R for seven consecutive days. The neuroprotective effects of EA were measured by neurobehavioral evaluation, triphenyltetrazolium chloride staining, hematoxylin-eosin staining and transmission electron microscopy. Oxidative stress, inflammatory factors, neural apoptosis and microglial activation were examined by enzyme-linked immunosorbent assay, immunofluorescence and reverse transcriptase polymerase chain reaction. Western blotting was used to assess PPAR-γ-mediated signaling.

RESULTS

We found that EA significantly alleviated cerebral I/R-induced infarct volume, decreased neurological scores and inhibited I/R-induced oxidative stress, inflammatory responses and microglial activation. EA also increased PPAR-γ protein expression. Furthermore, the protective effects of EA were reversed by injection of the PPAR-γ antagonist T0070907.

CONCLUSION

EA attenuates cerebral I/R injury by regulating oxidative stress, neuronal death and neuroinflammation via stimulation of PPAR-γ.

Ultrasonic Coating of Poly(D,L-lactic acid)/Poly(lactic-co-glycolic acid) Electrospun Fibers with ZnO Nanoparticles to Increase Angiogenesis in the CAM Assay

Critical-size bone defects necessitate bone void fillers that should be integrated well and be easily vascularized. One viable option is to use a biocompatible synthetic polymer and sonocoat it with zinc oxide (ZnO) nanoparticles (NPs). However, the ideal NP concentration and size must be assessed because a high dose of ZnO NPs may be toxic. Electrospun PDLLA/PLGA scaffolds were produced with different concentrations (0.5 or 1.0 s of sonocoating) and sizes of ZnO NPs (25 nm and 70 nm). They were characterized by SEM, EDX, ICP-OES, and the water contact angle. Vascularization and integration into the surrounding tissue were assessed with the CAM assay in the living chicken embryo. SEM, EDX, and ICP-OES confirmed the presence of ZnO NPs on polymer fibers. Sonocoated ZnO NPs lowered the WCA compared with the control. Smaller NPs were more pro-angiogenic exhibiting a higher vessel density than the larger NPs. At a lower concentration, less but larger vessels were visible in an environment with a lower cell density. Hence, the favored combination of smaller ZnO NPs at a lower concentration sonocoated on PDLLA/PLGA electrospun meshes leads to an advanced state of tissue integration and vascularization, providing a valuable synthetic bone graft to be used in clinics in the future.

Phytochemical profiling, cytotoxic, anti-migration, and anti-angiogenic potential of phenolic-rich fraction from Peganum harmala: in vitro and in ovo studies

Peganum harmala has been extensively employed in Algerian traditional medicine practices. This study aimed to explore the impact of n-butanol (n-BuOH) extract sourced from Peganum harmala seeds on cell proliferation, cell migration, and angiogenesis inhibition. Cytotoxic potential of n-BuOH extract was evaluated using MTT (3-(4,5-dimethylthiazol-2-yl) 2,5 diphenyltetrazolium bromide) assay against human breast adenocarcinoma MCF-7 cells, cell migration was determined using scratch assay, and anti-angiogenic effect was evaluated through macroscopic and histological examinations conducted on chick embryo chorioallantoic membrane. Additionally, this research estimated the phytochemical profile of n-BuOH extract. Fifteen phenolic compounds were identified using Ultra-performance liquid chromatography UPLC-ESI-MS-MS analysis. In addition, the n-BuOH extract of P. harmala exhibited potent antioxidant and free radical scavenging properties. The n-BuOH extract showed potent cytotoxicity against MCF-7 cell with an IC50 value of 8.68 ± 1.58 μg/mL. Furthermore, n-BuOH extract significantly reduced migration. A strong anti-angiogenic activity was observed in the groups treated with n-BuOH extract in comparison to the negative control. Histological analysis confirmed the anti-angiogenic effect of the n-BuOH extract. This activity is probably a result of the synergistic effects produced by different polyphenolic classes.

The Role of NRF2 in Cerebrovascular Protection: Implications for Vascular Cognitive Impairment and Dementia (VCID)

Vascular cognitive impairment and dementia (VCID) represents a broad spectrum of cognitive decline secondary to cerebral vascular aging and injury. It is the second most common type of dementia, and the prevalence continues to increase. Nuclear factor erythroid 2-related factor 2 (NRF2) is enriched in the cerebral vasculature and has diverse roles in metabolic balance, mitochondrial stabilization, redox balance, and anti-inflammation. In this review, we first briefly introduce cerebrovascular aging in VCID and the NRF2 pathway. We then extensively discuss the effects of NRF2 activation in cerebrovascular components such as endothelial cells, vascular smooth muscle cells, pericytes, and perivascular macrophages. Finally, we summarize the clinical potential of NRF2 activators in VCID.

Oxidative Stress and Cerebral Vascular Tone: The Role of Reactive Oxygen and Nitrogen Species

The brain's unique characteristics make it exceptionally susceptible to oxidative stress, which arises from an imbalance between reactive oxygen species (ROS) production, reactive nitrogen species (RNS) production, and antioxidant defense mechanisms. This review explores the factors contributing to the brain's vascular tone's vulnerability in the presence of oxidative damage, which can be of clinical interest in critically ill patients or those presenting acute brain injuries. The brain's high metabolic rate and inefficient electron transport chain in mitochondria lead to significant ROS generation. Moreover, non-replicating neuronal cells and low repair capacity increase susceptibility to oxidative insult. ROS can influence cerebral vascular tone and permeability, potentially impacting cerebral autoregulation. Different ROS species, including superoxide and hydrogen peroxide, exhibit vasodilatory or vasoconstrictive effects on cerebral blood vessels. RNS, particularly NO and peroxynitrite, also exert vasoactive effects. This review further investigates the neuroprotective effects of antioxidants, including superoxide dismutase (SOD), vitamin C, vitamin E, and the glutathione redox system. Various studies suggest that these antioxidants could be used as adjunct therapies to protect the cerebral vascular tone under conditions of high oxidative stress. Nevertheless, more extensive research is required to comprehensively grasp the relationship between oxidative stress and cerebrovascular tone, and explore the potential benefits of antioxidants as adjunctive therapies in critical illnesses and acute brain injuries.

Antioxidant and Anti-Inflammatory Effects of Garlic in Ischemic Stroke: Proposal of a New Mechanism of Protection through Regulation of Neuroplasticity

Stroke represents one of the main causes of death and disability in the world; despite this, pharmacological therapies against stroke remain insufficient. Ischemic stroke is the leading etiology of stroke. Different molecular mechanisms, such as excitotoxicity, oxidative stress, and inflammation, participate in cell death and tissue damage. At a preclinical level, different garlic compounds have been evaluated against these mechanisms. Additionally, there is evidence supporting the participation of garlic compounds in other mechanisms that contribute to brain tissue recovery, such as neuroplasticity. After ischemia, neuroplasticity is activated to recover cognitive and motor function. Some garlic-derived compounds and preparations have shown the ability to promote neuroplasticity under physiological conditions and, more importantly, in cerebral damage models. This work describes damage/repair mechanisms and the importance of garlic as a source of antioxidant and anti-inflammatory agents against damage. Moreover, we examine the less-explored neurotrophic properties of garlic, culminating in proposals and observations based on our review of the available information. The aim of the present study is to propose that garlic compounds and preparations could contribute to the treatment of ischemic stroke through their neurotrophic effects.

Naotaifang formula attenuates OGD/R-induced inflammation and ferroptosis by regulating microglial M1/M2 polarization through BMP6/SMADs signaling pathway

BACKGROUND

Cerebral ischemia-reperfusion injury (CIRI), a subsequent injury caused by thrombolytic reperfusion post ischemic stroke (IS). Naotaifang (NTF) formula, a novel traditional Chinese medicine (TCM) remedy against IS, was shown to exert beneficial effects in inhibiting inflammation and inhibiting lipid peroxide synthesis in our previous research.

PURPOSE

This study aimed to further explore the role of NTF in attenuating oxygen-glucose deprivation//reoxygenation (OGD/R)-induced inflammation and ferroptosis by regulating microglial M1/M2 polarization through the bone morphogenetic protein 6（BMP6）/SMADs signaling pathway.

METHODS

BV2 microglia were used to establish an OGD/R model. The effects of NTF on inflammation and ferroptosis in OGD/R-injured BV2 cells were separately detected by immunofluorescence assay, fluorescent probe, DCFH-DA flow cytometry, enzyme-linked immunosorbent assay, and western-blot.

RESULTS

The present results revealed that the M1 phenotype of microglia promoted the secretion of pro-inflammatory cytokines and aggravated ferroptosis and brain damage following OGD/R. However, an inhibitor of BMP6, LND-193189, reversed the aforementioned effects. Similarly, NTF promoted the shift of microglia from M1 to M2. Besides, NTF treatment effectively inhibited the expression of hepcidin, BMP6, SMADs and promoted the expression of ferroportin (FPN, SLC40A1) and γ-L-glutamyl-L-cysteinylglycine (glutathione or GSH) peroxidase 4 (GPX4).

CONCLUSION

Microglial M1/M2 polarization plays a pivotal role in inflammation and ferroptosis during OGD/R. The BMP6/SMADs signaling pathway is a potential therapeutical target of inflammation and ferroptosis induced by the transformation of microglia. Moreover, NTF could alleviate inflammation and ferroptosis through the BMP6/SMADs signaling pathway in OGD/R-injured microglia.

Association of serum uric acid and fasting plasma glucose with cognitive function: a cross-sectional study

BACKGROUND

The combined effect of serum uric acid (SUA) and blood glucose on cognition has not been explored. This study aimed to examine the separate and combined association of SUA and fasting plasma glucose (FPG) or diabetes mellitus (DM) with cognition in a sample of Chinese middle-aged and elderly population.

METHODS

A total of 6,509 participants aged 45 years or older who participated in the China Health and Retirement Longitudinal Study (CHARLS, 2011) were included. The three cognitive domains assessed were episodic memory, mental status, and global cognition (the sum of the first two terms). Higher scores indicated better cognition. SUA and FPG were measured. The participants were grouped based on SUA and FPG quartiles to evaluate their combined associations of cognition with SUA Q1-Q3 only (Low SUA), with FPG Q4 only (High FPG), without low SUA and high FPG levels (Non), and with low SUA and high FPG levels (Both), multivariate linear regression models were used to analyze their association.

RESULTS

Lower SUA quartiles were associated with poorer performance in global cognition and episodic memory compared with the highest quartile. Although no association was found between FPG or DM and cognition, high FPG or DM combined with low SUA levels in women (β_FPG = -0.983, 95% CI: -1.563--0.402; β_DM = -0.800, 95% CI: -1.369--0.232) had poorer cognition than those with low SUA level only (β_FPG = -0.469, 95% CI: -0.926--0.013; β_DM = -0.667, 95% CI: -1.060--0.275).

CONCLUSION

Maintaining an appropriate level of SUA may be important to prevent cognitive impairment in women with high FPG.

THE LEVEL OF REACTIVE OXYGEN SPECIES AS A MARKER OF ASTHMA SEVERITY IN CHILDREN

OBJECTIVE

The aim of the research was to assess the reactive oxygen species (ROS) levels in granulocytes of patients with asthma.

PATIENTS AND METHODS

Materials and methods: The study involved 35 children aged 5 to 17 years. 26 children with persistent asthma, partially controlled course in the period of exacerbation were divided into groups: 1 group - mild asthma (n = 12), group 2 - moderate asthma (n = 7) group 3 - severe asthma (n = 7) and control group included almost healthy children (n = 9). ROS levels in granulocytes were evaluated using BD FACSDiva™. The spirographic complex was used to assess the function of external respiration.

RESULTS

Results: The level of ROS in granulocytes of patients with severe asthma was significantly reduced compared with children in the control group and patients with mild and moderate asthma (p₁-₃ = 0.0003, p₂-₃ = 0.0017, p c-₃ = 0.0150). The concentration of ROS in granulocytes ≤ 285 a.u. was prognostically significant with high specificity and sensitivity with severe asthma.

CONCLUSION

Conclusions: The concentration of ROS levels in neutrophils in patients with severe asthma probably reflected the suppression of their products, which suggests the depletion of the reserve capacity of neutrophils. Decreased concentrations of reactive oxygen species in children with asthma can be considered as a possible marker of asthma severity.

Molecular mechanisms behind ROS regulation in cancer: A balancing act between augmented tumorigenesis and cell apoptosis

ROS include hydroxyl radicals (HO^.), superoxide (O₂^..), and hydrogen peroxide (H₂O₂). ROS are typically produced under physiological conditions and play crucial roles in living organisms. It is known that ROS, which are created spontaneously by cells through aerobic metabolism in mitochondria, can have either a beneficial or detrimental influence on biological systems. Moderate levels of ROS can cause oxidative damage to proteins, DNA and lipids, which can aid in the pathogenesis of many disorders, including cancer. However, excessive concentrations of ROS can initiate programmed cell death in cancer. Presently, a variety of chemotherapeutic drugs and herbal agents are being investigated to induce ROS-mediated cell death in cancer. Therefore, preserving ROS homeostasis is essential for ensuring normal cell development and survival. On account of a significant association of ROS levels at various concentrations with carcinogenesis in a number of malignancies, further studies are needed to determine the underlying molecular mechanisms and develop the possibilities for intervening in these processes.

The Mechanism Underlying the Regulation of Long Non-coding RNA MEG3 in Cerebral Ischemic Stroke

Cerebral ischemic stroke is one of the leading causes of morbidity and mortality worldwide, and rapidly increasing annually with no more effective therapeutic measures. Thus, the novel diagnostic and prognostic biomarkers are urgent to be identified for prevention and therapy of ischemic stroke. Recently, long noncoding RNAs (lncRNAs), a major family of noncoding RNAs with more than 200 nucleotides, have been considered as new targets for modulating pathological process of ischemic stroke. In this review, we summarized that the lncRNA-maternally expressed gene 3 (MEG3) played a critical role in promotion of neuronal cell death and inhibition of angiogenesis in response to hypoxia or ischemia condition, and further described the challenge of overcrossing blood-brain barrier (BBB) and determination of optimal carrier for delivering lncRNA' drugs into the specific brain regions. In brief, MEG3 will be a potential diagnostic biomarker and drug target in treatment and therapy of ischemic stroke in the future.

Oxidative Stress and Extracellular Matrix Remodeling Are Signature Pathways of Extracellular Vesicles Released upon Morphine Exposure on Human Brain Microvascular Endothelial Cells

Morphine, a commonly used antinociceptive drug in hospitals, is known to cross the blood-brain barrier (BBB) by first passing through brain endothelial cells. Despite its pain-relieving effect, morphine also has detrimental effects, such as the potential induction of redox imbalance in the brain. However, there is still insufficient evidence of these effects on the brain, particularly on the brain endothelial cells and the extracellular vesicles that they naturally release. Indeed, extracellular vesicles (EVs) are nanosized bioparticles produced by almost all cell types and are currently thought to reflect the physiological state of their parent cells. These vesicles have emerged as a promising source of biomarkers by indicating the functional or dysfunctional state of their parent cells and, thus, allowing a better understanding of the biological processes involved in an adverse state. However, there is very little information on the morphine effect on human brain microvascular endothelial cells (HBMECs), and even less on their released EVs. Therefore, the current study aimed at unraveling the detrimental mechanisms of morphine exposure (at 1, 10, 25, 50 and 100 µM) for 24 h on human brain microvascular endothelial cells as well as on their associated EVs. Isolation of EVs was carried out using an affinity-based method. Several orthogonal techniques (NTA, western blotting and proteomics analysis) were used to validate the EVs enrichment, quality and concentration. Data-independent mass spectrometry (DIA-MS)-based proteomics was applied in order to analyze the proteome modulations induced by morphine on HBMECs and EVs. We were able to quantify almost 5500 proteins in HBMECs and 1500 proteins in EVs, of which 256 and 148, respectively, were found to be differentially expressed in at least one condition. Pathway enrichment analysis revealed that the "cell adhesion and extracellular matrix remodeling" process and the "HIF1 pathway", a pathway related to oxidative stress responses, were significantly modulated upon morphine exposure in HBMECs and EVs. Altogether, the combination of proteomics and bioinformatics findings highlighted shared pathways between HBMECs exposed to morphine and their released EVs. These results put forward molecular signatures of morphine-induced toxicity in HBMECs that were also carried by EVs. Therefore, EVs could potentially be regarded as a useful tool to investigate brain endothelial cells dysfunction, and to a different extent, the BBB dysfunction in patient circulation using these "signature pathways".

miRNA Involvement in Cerebral Ischemia-Reperfusion Injury

Cerebral ischemia reperfusion injury is a debilitating medical condition, currently with only a limited amount of therapies aimed at protecting the cerebral parenchyma. Micro RNAs (miRNAs) are small, non-coding RNA molecules that via the RNA-induced silencing complex either degrade or prevent target messenger RNAs from being translated and thus, can modulate the synthesis of target proteins. In the neurological field, miRNAs have been evaluated as potential regulators in brain development processes and pathological events. Following ischemic hypoxic stress, the cellular and molecular events initiated dysregulate different miRNAs, responsible for long-terming progression and extension of neuronal damage. Because of their ability to regulate the synthesis of target proteins, miRNAs emerge as a possible therapeutic strategy in limiting the neuronal damage following a cerebral ischemic event. This review aims to summarize the recent literature evidence of the miRNAs involved in signaling and modulating cerebral ischemia-reperfusion injuries, thus pointing their potential in limiting neuronal damage and repair mechanisms. An in-depth overview of the molecular pathways involved in ischemia reperfusion injury and the involvement of specific miRNAs, could provide future perspectives in the development of neuroprotective agents targeting these specific miRNAs.

Propionate ameliorates diabetes-induced neurological dysfunction through regulating the PI3K/Akt/eNOS signaling pathway

A large body of research has established diabetes-related cognitive deterioration, sometimes known as "diabetic encephalopathy". Current evidence supports that oxidative stress, neuronal apoptosis, and cerebral microcirculation weakness are associated with cognition deficits induced by diabetes. The present study explores the effect of propionate on neurological deficits, cerebral blood flow, and oxidative stress in diabetic mice. Propionate in different doses (37.5, 75 and 150 mg/kg) was orally administrated daily. Here, we show that propionate can markedly improve neurological function, which is correlated with its capabilities of stimulating nitrogen monoxide (NO) production, increasing cerebral microcirculation, suppressing oxidative stress, and reducing neuron loss in the hippocampus. In addition, the results of Western Blotting indicated that the brain-protective function of propionate in streptozocin (STZ)-induced type 1 diabetes mellitus (T1DM) mice is related to phosphoinositide 3-kinase (PI3K)/serine-threonine protein kinase (Akt)/endothelial nitrogen monoxide synthase (eNOS) signaling pathway. In a diabetic mouse model, propionate reduces cerebral microcirculation, hippocampus apoptosis, and neurological impairment. Thus, propionate, now employed as a food preservative, may also help slow diabetes-induced cognitive loss.

Mechanisms Underlying Curcumin-Induced Neuroprotection in Cerebral Ischemia

Ischemic stroke is the leading cause of death and disability worldwide, and restoring the blood flow to ischemic brain tissues is currently the main therapeutic strategy. However, reperfusion after brain ischemia leads to excessive reactive oxygen species production, inflammatory cell recruitment, the release of inflammatory mediators, cell death, mitochondrial dysfunction, endoplasmic reticulum stress, and blood-brain barrier damage; these pathological mechanisms will further aggravate brain tissue injury, ultimately affecting the recovery of neurological functions. It has attracted the attention of researchers to develop drugs with multitarget intervention effects for individuals with cerebral ischemia. A large number of studies have established that curcumin plays a significant neuroprotective role in cerebral ischemia via various mechanisms, including antioxidation, anti-inflammation, anti-apoptosis, protection of the blood-brain barrier, and restoration of mitochondrial function and structure, restoring cerebral circulation, reducing infarct volume, improving brain edema, promoting blood-brain barrier repair, and improving the neurological functions. Therefore, summarizing the results from the latest literature and identifying the potential mechanisms of action of curcumin in cerebral ischemia will serve as a basis and guidance for the clinical applications of curcumin in the future.

1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline exerts a neuroprotective effect and normalises redox homeostasis in a rat model of cerebral ischemia/reperfusion

Ischemia is one of the main etiological factors of stroke and is associated with the development of energy deficiency, oxidative stress, and inflammation. An abrupt restoration of blood flow, called reperfusion, can worsen the effects of ischemia. In our study, we assessed the neuroprotective potential of 1-benzoyl-6-hydroxy-2,2,4-trimethyl-1,2-dihydroquinoline (BHDQ) in cerebral ischemia/reperfusion (CIR) in rats. Wistar rats, divided into 4 groups were used in the study: sham-operated animals; animals with CIR caused by occlusion of the common carotid arteries and subsequent removal of the occlusions; rats treated with BHDQ at a dose of 50 mg/kg in the presence of pathology; sham-operated animals treated with BHDQ. The analysis of the state of energy metabolism in the brain, the level of the S100B protein and the histological assessment of the brain tissue were carried out. The antioxidant potential of BHDQ was assessed by measuring biochemiluminescence parameters, analysing the level of 8-isoprostane, products of lipid and protein oxidation, concentration of α-tocopherol and citrate, and aconitate hydratase activity during CIR in rats. A study of the effect of BHDQ on the regulation of the enzymatic antioxidant system and the inflammatory processes was performed. We demonstrated that BHDQ has a neuroprotective effect in CIR, reducing histopathological changes in the brain, normalizing pyruvate and lactate concentrations, and the transcripts level of Hif-1α gene. The positive effect of BHDQ was probably due to its antioxidant and anti-inflammatory activity, manifested in a decrease in the parameters of the oxidative stress, decreased mRNA of proinflammatory cytokines and NF-κB factor genes. In addition, BHDQ reduced the load on antioxidant protection enzymes, contributing to a change in their activities, decreased the level of antioxidant gene transcripts and expression of Nrf2 and Foxo1 factors toward control. Thus, BHDQ exhibited a neuroprotective effect due to a decrease in the level of oxidative stress and inflammation and the normalization of redox homeostasis on CIR in rats.

Bioactive Materials Promote Wound Healing through Modulation of Cell Behaviors

Skin wound repair is a multistage process involving multiple cellular and molecular interactions, which modulate the cell behaviors and dynamic remodeling of extracellular matrices to maximize regeneration and repair. Consequently, abnormalities in cell functions or pathways inevitably give rise to side effects, such as dysregulated inflammation, hyperplasia of nonmigratory epithelial cells, and lack of response to growth factors, which impedes angiogenesis and fibrosis. These issues may cause delayed wound healing or even non-healing states. Current clinical therapeutic approaches are predominantly dedicated to preventing infections and alleviating topical symptoms rather than addressing the modulation of wound microenvironments to achieve targeted outcomes. Bioactive materials, relying on their chemical, physical, and biological properties or as carriers of bioactive substances, can affect wound microenvironments and promote wound healing at the molecular level. By addressing the mechanisms of wound healing from the perspective of cell behaviors, this review discusses how bioactive materials modulate the microenvironments and cell behaviors within the wounds during the stages of hemostasis, anti-inflammation, tissue regeneration and deposition, and matrix remodeling. A deeper understanding of cell behaviors during wound healing is bound to promote the development of more targeted and efficient bioactive materials for clinical applications.

Physical Activity vs. Redox Balance in the Brain: Brain Health, Aging and Diseases

It has been proven that physical exercise improves cognitive function and memory, has an analgesic and antidepressant effect, and delays the aging of the brain and the development of diseases, including neurodegenerative disorders. There are even attempts to use physical activity in the treatment of mental diseases. The course of most diseases is strictly associated with oxidative stress, which can be prevented or alleviated with regular exercise. It has been proven that physical exercise helps to maintain the oxidant–antioxidant balance. In this review, we present the current knowledge on redox balance in the organism and the consequences of its disruption, while focusing mainly on the brain. Furthermore, we discuss the impact of physical activity on aging and brain diseases, and present current recommendations and directions for further research in this area.

Beneficial Oxidative Stress-Related trans-Resveratrol Effects in the Treatment and Prevention of Breast Cancer

Resveratrol is one of the most investigated polyphenols for its multiple biological activities and many beneficial effects. These are mainly related to its ability to scavenge free radicals and reduce oxidative stress. Resveratrol has also been shown to have the ability to stimulate the production of antioxidant enzymes, which interact with numerous signaling pathways involved in tumor development, and to possess side effects associated with the use of chemotherapy drugs. In this review article we summarized the main discoveries about the impact resveratrol can have in helping to prevent, as well as adjuvant treating, breast cancer. A brief overview of the primary sources of resveratrol as well as some approaches for improving its bioavailability have been also discussed.

Engeletin protects against cerebral ischemia/reperfusion injury by modulating the VEGF/vasohibin and Ang-1/Tie-2 pathways

Engeletin is a natural derivative of Smilax glabra rhizomilax that exhibits anti-inflammatory activity and suppresses lipid peroxidation. In the present study, we sought to elucidate the mechanistic basis for the neuroprotective and pro-angiogenic activity of engeltin in a human umbilical vein endothelial cells (HUVECs) oxygen-glucose deprivation and reoxygenation (OGD/R) model system and a middle cerebral artery occlusion (MCAO) rat model of cerebral ischemia and reperfusion injury. These analyses revealed that engeletin (10, 20, or 40 mg/kg) was able to reduce the infarct volume, increase cerebral blood flow, improve neurological function, and bolster the expression of vascular endothelial growth factor (VEGF), vasohibin-2 (Vash-2), angiopoietin-1 (Ang-1), phosphorylated human angiopoietin receptor tyrosine kinase 2 (p-Tie2), and platelet endothelial cell adhesion molecule-1 (PECAM-1/CD31) in MCAO rats. Similarly, engeletin (100, 200, or 400 nM) markedly enhanced the migration, tube formation, and VEGF expression of HUVECs in an OGD/R model system, while the VEGF receptor (R) inhibitor axitinib reversed the observed changes in HUVEC tube formation activity and Vash-2, VEGF, and CD31 expression. These data suggested that engeletin exhibited significant neuroprotective effects against cerebral ischemia and reperfusion injury in rats, and improved cerebrovascular angiogenesis by modulating the VEGF/vasohibin and Ang-1/Tie-2 pathways.

Mesenchymal Stem Cell Transplantation for Ischemic Diseases: Mechanisms and Challenges

Ischemic diseases are conditions associated with the restriction or blockage of blood supply to specific tissues. These conditions can cause moderate to severe complications in patients, and can lead to permanent disabilities. Since they are blood vessel-related diseases, ischemic diseases are usually treated with endothelial cells or endothelial progenitor cells that can regenerate new blood vessels. However, in recent years, mesenchymal stem cells (MSCs) have shown potent bioeffects on angiogenesis, thus playing a role in blood regeneration. Indeed, MSCs can trigger angiogenesis at ischemic sites by several mechanisms related to their trans-differentiation potential. These mechanisms include inhibition of apoptosis, stimulation of angiogenesis via angiogenic growth factors, and regulation of immune responses, as well as regulation of scarring to suppress blood vessel regeneration when needed. However, preclinical and clinical trials of MSC transplantation in ischemic diseases have shown some limitations in terms of treatment efficacy. Such studies have emphasized the current challenges of MSC-based therapies. Treatment efficacy could be enhanced if the limitations were better understood and potentially resolved. This review will summarize some of the strategies by which MSCs have been utilized for ischemic disease treatment, and will highlight some challenges of those applications as well as suggesting some strategies to improve treatment efficacy.

Differentially expressed genes induced by β-caryophyllene in a rat model of cerebral ischemia-reperfusion injury

Experimental studies have shown that β-caryophyllene (BCP) improved neurological deficits of cerebral ischemia-reperfusion injury (CIRI) rats resulting from Middle Cerebral Artery Occlusion (MCAO). However, research on targets of BCP on CIRI has not been completed. In this study, the mRNA sequencing was used to distinguish various therapeutic multiple targets of BCP on CIRI. Differentially expressed genes (DEGs) were identified from RNA-seq analysis. CIRI induced up-regulated genes (CIRI vs. Sham) and BCP -induced down-regulated genes (BCP vs CIRI) were identified. Significant DEGs were identified only that expressed in each of all samples. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis of significant DEGs were determined by cluster Profiler. Protein interactive network (PPI) was analyzed using the String tool and Hub genes was identified by cytoHubba. Transcription factor (TF) regulatory network for the potential Hub genes was constructed. Western blot and ELISA were used to verified hub genes and relative inflammatory cytokines. After mRNA sequencing, a total of 411 DEGs were filtered based on the 2 series (CIRI vs. Sham and CIRI vs. BCP), with Pax1, Cxcl3 and Ccl20 are the most remarkable ones reversed by BCP. GO analysis was represented by DEGs involved in multiple biological process such as extra-cellular matrix organization, leukocyte migration, regulation of angiogenesis, reactive oxygen species metabolic process, etc. KEGG analysis showed that DEGs participated several signaling pathways including MAPK signaling pathway (rno04010), Cytokine-cytokine receptor interaction (rno04060), JAK-STAT signaling pathway (rno04630), and others. The protein-protein interaction (PPI) network consisted of 339 nodes and 1945 connections, and top ten Hub genes were identified by cytoHubba such as TIMP1, MMP-9, and STAT3. Subsequently, a TFs-miRNAs-targets regulatory network was established, involving 6 TFs, 5 miRNAs, and 10 hub genes, consisting of several regulated models such as Brd4 - rno-let-7e - Mmp9, Brd4 - rno-let-7i - Stat3, and Hnf4a- rno-let-7b -Timp1. Finally, western blot demonstrated that BCP could inhibit the increased TIMP1, MMP-9 and STAT3 expression in rat brains after I/R. ELISA represented that BCP could suppress inflammatory cytokines caused by CIRI and present anti-oxidative property. In conclusion, this study shows that the intervention of BCP can significantly reduce neurologic deficit, improve the cerebral ischemia, and a total of ten hub genes were found closely related to the treatment of BCP on CIRI. Prudent experimental validation suggests that the BCP might have the neuro-protective effects in CIRI by decreasing the expression of MMP-9 and TIMP-1, STAT3. In a sense, this study reveals that the MMP-9/TIMP-1 signaling pathway may be involved in the injury after CIRI and thus provides a new treatment strategy as well as a researching method for stroke.

[Lithium ascorbate as a cerebroprotective agent in a model of ischemic stroke]

INTRODUCTION

Ischemic stroke is one of the most severe neurological pathologies with high mortality and disability. In this connection, the development and study of new drugs for the prevention and treatment of stroke is an extremely important task. A new approach to neuroprotection is the use of lithium salts with antioxidant activity.

AIM

To study the cerebroprotective effect of lithium ascorbate on a rat model of ischemic stroke.

MATERIAL AND METHODS

Test samples of lithium ascorbate were synthesized ex tempore for an experiment using reagents of ACS qualification (Sigma-Aldrich). The ischemic stroke model was realized using the filament occlusion of the middle cerebral artery in rats of the Sprague Dawley line according to standardized procedure. Neurological examination of the animals, histological study of brain tissue with staining of brain sections, and calculating the volume of cerebral infarction were performed.

RESULTS AND CONCLUSION

There is a significant cerebroprotective effect of lithium ascorbate expressed in a multiple decrease in the volume of the zone of cerebral infarction (by 75% of the control group indicator) and the absence of mortality in the experimental group of animals. Newly discovered distinct anti-stroke effect of lithium ascorbate in combination with low toxicity could be considered promising for further clinical studies and practical application in neurology.

Curcumin inhibits alloxan-induced pancreatic islet cell damage via antioxidation and antiapoptosis

The present study elucidates the possible protective effects of curcumin on β-cells damaged by oxidative stress and its significance in controlling diabetes mellitus in in vitro experiments. Pancreatic islet (RIN-m5F) cells were treated with 25 mmol/L alloxan (AXN) to induce cell damage and the protective effects of curcumin were observed. The results showed that curcumin significantly promoted the cellular activity of AXN-treated RIN-m5F cells, decreased the ratio of apoptosis, downregulated the level of malondialdehyde, upregulated the levels of superoxide dismutase and reactive oxygen species, increased the expression of Bcl-2, cleaved caspase-3, and cleaved PARP1, and decreased the expression of Bax in AXN-treated cells. These results suggest that curcumin inhibits AXN-induced damage in RIN-m5F cells via antioxidative and antiapoptotic mechanisms.

Reactive oxygen species or reactive sulfur species: why we should consider the latter

The biological effects of oxidants, especially reactive oxygen species (ROS), include signaling functions (oxidative eustress), initiation of measures to reduce elevated ROS (oxidative stress), and a cascade of pathophysiological events that accompany excessive ROS (oxidative distress). Although these effects have long been studied in animal models with perturbed ROS, their actions under physiological conditions are less clear. I propose that some of the apparent uncertainty may be due to confusion of ROS with endogenously generated reactive sulfur species (RSS). ROS and RSS are chemically similar, but RSS are more reactive and versatile, and can be stored and reused. Both ROS and RSS signal via oxidation reactions with protein cysteine sulfur and they produce identical effector responses, but RSS appear to be more effective. RSS in the form of persulfidated cysteines (Cys-S-S) are produced endogenously and co-translationally introduced into proteins, and there is increasing evidence that many cellular proteins are persulfidated. A number of practical factors have contributed to confusion between ROS and RSS, and these are discussed herein. Furthermore, essentially all endogenous antioxidant enzymes appeared shortly after life began, some 3.8 billion years ago, when RSS metabolism dominated evolution. This was long before the rise in ROS, 600 million years ago, and I propose that these same enzymes, with only minor modifications, still effectively metabolize RSS in extant organisms. I am not suggesting that all ROS are RSS; however, I believe that the relative importance of ROS and RSS in biological systems needs further consideration.

Insights into the angiogenic effects of nanomaterials: mechanisms involved and potential applications

The vascular system, which transports oxygen and nutrients, plays an important role in wound healing, cardiovascular disease treatment and bone tissue engineering. Angiogenesis is a complex and delicate regulatory process. Vascular cells, the extracellular matrix (ECM) and angiogenic factors are indispensable in the promotion of lumen formation and vascular maturation to support blood flow. However, the addition of growth factors or proteins involved in proangiogenic effects is not effective for regulating angiogenesis in different microenvironments. The construction of biomaterial scaffolds to achieve optimal growth conditions and earlier vascularization is undoubtedly one of the most important considerations and major challenges among engineering strategies. Nanomaterials have attracted much attention in biomedical applications due to their structure and unique photoelectric and catalytic properties. Nanomaterials not only serve as carriers that effectively deliver factors such as angiogenesis-related proteins and mRNA but also simulate the nano-topological structure of the primary ECM of blood vessels and stimulate the gene expression of angiogenic effects facilitating angiogenesis. Therefore, the introduction of nanomaterials to promote angiogenesis is a great helpful to the success of tissue regeneration and some ischaemic diseases. This review focuses on the angiogenic effects of nanoscaffolds in different types of tissue regeneration and discusses the influencing factors as well as possible related mechanisms of nanomaterials in endothelial neovascularization. It contributes novel insights into the design and development of novel nanomaterials for vascularization and therapeutic applications.

Stanniocalcin-1 ameliorates cerebral ischemia by decrease oxidative stress and blood brain barrier permeability

Blood brain barrier (BBB) permeability and oxidative stress have been reported to be important mechanisms for brain damage following ischemic stroke and stanniocalcin-1 (STC-1), a neuroprotective protein, has anti-inflammatory and anti-oxidative stress properties. Herein, we report the effect of STC-1 on BBB permeability and brain oxidative stress after stroke in an animal model. Male Wistar received an intracerebroventricularly injection of human recombinant STC-1 (100 ng/kg) or saline and were subjected to sham procedure or global cerebral ischemia/reperfusion (I/R) model. Six and 24 h after I/R, neurological evaluation was performed; at 24 h brain water content was evaluated in the total brain, and BBB permeability, nitrite/nitrate (N/N) concentration, lipid peroxidation, protein carbonyls formation, superoxide dismutase (SOD) and catalase (CAT) activity were determined in the hippocampus, cortex, prefrontal cortex, striatum and cerebellum. Rats exhibited neurological deficit at 6 and 24 h after I/R and STC-1 reduction at 24 h. After I/R there were an increase of brain water content, BBB permeability in the hippocampus, cortex and pre-frontal cortex and N/N in the hippocampus, and STC-1 decreased this level only in the hippocampus. STC-1 decreased lipid peroxidation in the hippocampus, cortex and prefrontal cortex and protein oxidative damage in the hippocampus and cortex. SOD activity decreased in the hippocampus, cortex and prefrontal cortex after I/R and STC-1 reestablished these levels in the hippocampus and cortex. CAT activity decreased only in the hippocampus and cortex and STC-1 increased the CAT activity in the hippocampus. Our data provide the first experimental demonstration that STC-1 reduced brain dysfunction associated with cerebral I/R in rats, by decreasing BBB permeability and oxidative stress parameters.

Betulinic Acid Enhances the Viability of Random-Pattern Skin Flaps by Activating Autophagy

Random-pattern skin flap replantation is commonly used to repair skin defects during plastic and reconstructive surgery. However, flap necrosis due to ischemia and ischemia-reperfusion injury limits clinical applications. Betulinic acid, a plant-derived pentacyclic triterpene, may facilitate flap survival. In the present study, the effects of betulinic acid on flap survival and the underlying mechanisms were assessed. Fifty-four mice with a dorsal random flap model were randomly divided into the control, betulinic acid group, and the betulinic acid + 3-methyladenine group. These groups were treated with dimethyl sulfoxide, betulinic acid, and betulinic acid plus 3-methyladenine, respectively. Flap tissues were acquired on postoperative day 7 to assess angiogenesis, apoptosis, oxidative stress, and autophagy. Betulinic acid promoted survival of the skin flap area, reduced tissue edema, and enhanced the number of microvessels. It also enhanced angiogenesis, attenuated apoptosis, alleviated oxidative stress, and activated autophagy. However, its effects on flap viability and angiogenesis, apoptosis, and oxidative stress were reversed by the autophagy inhibitor 3-methyladenine. Our findings reveal that betulinic acid improves survival of random-pattern skin flaps by promoting angiogenesis, dampening apoptosis, and alleviating oxidative stress, which mediates activation of autophagy.

Processing milk causes the formation of protein oxidation products which impair spatial learning and memory in rats

This study explored the effects of protein oxidation during milk processing on spatial learning and memory in rats. Increasing the heating time, fat content, and inlet air temperature during processing by boiling, microwave heating, spray-drying, or freeze-drying increases milk protein oxidation. Oxidative damage done to milk proteins by microwave heating is greater than that caused by boiling. Dityrosine (DT), as a kind of tyrosine oxidation product, is the most important marker of this process, especially during spray-drying. Rats received diets containing either SWM (spray-dried milk powder diet), FWM (freeze-dried milk powder diet), FWM + LDT (freeze-dried milk powder + low dityrosine diet, DT: 1.4 mg kg-1), or FWM + HDT (freeze-dried milk powder + high dityrosine diet, DT: 2.8 mg kg-1) for 6 weeks. We found that the SWM group, the FWM + LDT group, and the FWM + HDT group appeared to have various degrees of redox state imbalance and oxidative damage in plasma, liver, and brain tissues. Further, hippocampal inflammatory and apoptosis genes were significantly up-regulated in such groups, while learning and memory genes were significantly down-regulated. Eventually, varying degrees of spatial learning and memory impairment were demonstrated in those groups in the Morris water maze. This means that humans should control milk protein oxidation and improve the processing methods applied to food.