Progress of Ferroptosis in Ischemic Stroke and Therapeutic Targets.

Ferroptosis is an iron-dependent form of programmed cell death (PCD) and ischemic stroke (IS) has been confirmed to be closely related to ferroptosis. The mechanisms of ferroptosis were summarized into three interrelated aspects: iron metabolism, lipid peroxide metabolism, as well as glutathione and amino acid metabolism. What's more, the causal relationship between ferroptosis and IS has been elucidated by several processes. The disruption of the blood-brain barrier, the release of excitatory amino acids, and the inflammatory response after ischemic stroke all lead to the disorder of iron metabolism and the antioxidant system. Based on these statements, we reviewed the reported effects of compounds and drugs treating IS by modulating key molecules in ferroptosis. Through detailed analysis of the roles of these key molecules, we have also more clearly demonstrated the essential effect of ferroptosis in the occurrence of IS so as to provide new targets and ideas for the therapeutic targets of IS.

P-Glycoprotein Exacerbates Brain Injury Following Experimental Cerebral Ischemia by Promoting Proinflammatory Microglia Activation.

Microglia are activated following cerebral ischemic insult. P-glycoprotein (P-gp) is an efflux transporter on microvascular endothelial cells and upregulated after cerebral ischemia. This study evaluated the effects and possible mechanisms of P-gp on microglial polarization/activation in mice after ischemic stroke. P-gp-specific siRNA and adeno-associated virus (p-AAV) were used to silence and overexpress P-gp, respectively. Middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation (OGD/R) were performed in mice and cerebral microvascular endothelial cells (bEnd.3) in vitro, respectively. OGD/R-injured bEnd.3 cells were cocultured with mouse microglial cells (BV2) in Transwell. Influences on acute ischemic stroke outcome, the expression of inflammatory cytokines, and chemokines and chemokines receptors, microglial polarization, glucocorticoid receptor (GR) nuclear translocation, and GR-mediated mRNA decay (GMD) activation were evaluated via reverse transcription real-time polymerase chain reaction, western blot, or immunofluorescence. Silencing P-gp markedly alleviated experimental ischemia injury as indicated by reduced cerebral infarct size, improved neurological deficits, and reduced the expression of interleukin-6 (IL-6) and IL-12 expression. Silencing P-gp also mitigated proinflammatory microglial polarization and the expression of C-C motif chemokine ligand 2 (CCL2) and its receptor CCR2 expression, whereas promoted anti-inflammatory microglia polarization. Additionally, P-gp silencing promoted GR nuclear translocation and the expression of GMD relative proteins in endothelial cells. Conversely, overexpressing P-gp via p-AAV transfection offset all these effects. Furthermore, silencing endothelial GR counteracted all effects mediated by silencing or overexpressing P-gp. Elevated P-gp expression aggravated inflammatory response and brain damage after ischemic stroke by augmenting proinflammatory microglial polarization in association with increased endothelial CCL2 release due to GMD inhibition by P-gp.

Tripartite Motif Protein Family in Central Nervous System Diseases.

Tripartite motif (TRIM) protein superfamily is a group of E3 ubiquitin ligases characterized by the conserved RING domain, the B-box domain, and the coiled-coil domain (RBCC). It is widely involved in various physiological and pathological processes, such as intracellular signal transduction, cell cycle regulation, oncogenesis, and innate immune response. Central nervous system (CNS) diseases are composed of encephalopathy and spinal cord diseases, which have a high disability and mortality rate. Patients are often unable to take care of themselves and their life quality can be seriously declined. Initially, the function research of TRIM proteins mainly focused on cancer. However, in recent years, accumulating attention is paid to the roles they play in CNS diseases. In this review, we integrate the reported roles of TRIM proteins in the pathological process of CNS diseases and related signaling pathways, hoping to provide theoretical bases for further research in treating CNS diseases targeting TRIM proteins. TRIM proteins participated in CNS diseases. TRIM protein family is characterized by a highly conserved RBCC domain, referring to the RING domain, the B-box domain, and the coiled-coil domain. Recent research has discovered the relations between TRIM proteins and various CNS diseases, especially Alzheimer's disease, Parkinson's disease, and ischemic stroke.

CaMKII and CaV3.2 T-type calcium channel mediate Connexin-43-dependent inflammation by activating astrocytes in vincristine-induced neuropathic pain.

Vincristine (VCR), an alkaloid isolated from vinca, is a commonly used chemotherapeutic drug. However, VCR therapy can lead to dose-dependent peripheral neurotoxicity, mainly manifesting as neuropathic pain, which is one of the dominant reasons for limiting its utility. Experimentally, we discovered that VCR-induced neuropathic pain (VINP) was accompanied by astrocyte activation; the upregulation of phospho-CaMKII (p-CaMKII), CaV3.2, and Connexin-43 (Cx43) expression; and the production and release of inflammatory cytokines and chemokines in the spinal cord. Similar situations were also observed in astrocyte cultures. Interestingly, these alterations were all reversed by intrathecal injection of KN-93 (a CaMKII inhibitor) or L-Ascorbic acid (a CaV3.2 inhibitor). In addition, KN-93 and L-Ascorbic acid inhibited the increase in [Ca2+]i associated with astrocyte activation. We also verified that knocking down or inhibiting Cx43 level via intrathecal injection of Cx43 siRNA or Gap27 (a Cx43 mimetic peptide) relieved pain hypersensitivity and reduced the release of inflammatory factors; however, they did not affect astrocyte activation or p-CaMKII and CaV3.2 expression. Besides, the overexpression of Cx43 through the transfection of the Cx43 plasmid did not affect p-CaMKII and CaV3.2 expressions in vitro. Therefore, CaMKII and CaV3.2 may activate astrocytes by increasing [Ca2+]i, thereby mediating Cx43-dependent inflammation in VINP. Moreover, we demonstrated that the CaMKII signalling pathway was involved in VCR-induced inflammation, apoptosis, and mitochondrial damage. Collectively, our findings show a novel mechanism by which CaMKII and CaV3.2 mediate Cx43-dependent inflammation by activating astrocytes in neuropathic pain induced by VCR.

Circular RNAs: Promising Treatment Targets and Biomarkers of Ischemic Stroke.

Ischemic stroke is one of the most significant causes of morbidity and mortality worldwide. However, there is a dearth of effective drugs and treatment methods for ischemic stroke. Significant numbers of circular RNAs (circRNAs) exhibit abnormal expression following ischemic stroke and are considered potential therapeutic targets. CircRNAs have emerged as promising biomarkers due to their stable expression in peripheral blood and their potential significance in ischemic stroke diagnosis and prognosis. This review provides a summary of 31 circRNAs involved in the pathophysiological processes of apoptosis, autophagy, inflammation, oxidative stress, and angiogenesis following ischemic stroke. Furthermore, we discuss the mechanisms of action of said circRNAs and their potential clinical applications. Ultimately, circRNAs exhibit promise as both therapeutic targets and biomarkers for ischemic stroke.

Therapeutic effects of JLX001 on neuronal necroptosis after cerebral ischemia-reperfusion in rats.

In recent years, more attention has been given to novel patterns of cell death observed during ischemia/reperfusion (I/R). Necroptosis is a regulable secondary cell death pathway; necroptosis is different from traditional forms of cell death, and it is regulated by the RIPK1-RIPK3-MLKL signaling pathway. JLX001 is the double hydrochloride of the natural compound cyclovirobuxine D (CVB-D). Previous studies have confirmed that CVB-D exerts a significant effect on cardiovascular and cerebrovascular diseases and that JLX001 can reduce ischemic brain injury by inhibiting cell apoptosis. For the first time, this project explored the in vivo and in vitro inhibitory effects of the therapeutic administration of JLX001 on the neuronal necroptosis caused by cerebral ischemia-reperfusion injury (CIRI). The middle cerebral artery occlusion reperfusion (MCAO/R) model was used to simulate I/R injury in rats in vivo, and oxygen-glucose deprivation and reperfusion (OGD/R) was used to simulate I/R injury in vitro. After the administration of JLX001, the relative expression of necroptosis-related molecules was measured by ELISA, RT-PCR, HE staining, immunofluorescence and Western blotting. The results showed that JLX001 significantly reduced pathological damage and the cerebral infarction rate in rat brain tissues, and the expression of neuronal necroptosis-related molecules was reduced, suggesting that JLX001 may regulate CIRI through the classic RIPK1-RIPK3-MLKL necroptosis pathway.

P-Glycoprotein Aggravates Blood Brain Barrier Dysfunction in Experimental Ischemic Stroke by Inhibiting Endothelial Autophagy.

P-glycoprotein (P-gp) is expressed on brain microvessel endothelial cells of blood-brain barrier (BBB) and elevated after cerebral ischemia. In this study, we explored the influence and potential mechanisms of P-gp on BBB function in experimental ischemic stroke in vivo and in vitro. Middle cerebral artery occlusion/reperfusion (MCAO/R) was created in mice. Oxygen-glucose deprivation/reoxygenation (OGD/R) was performed in brain microvascular vessel-derived endothelial cells (bEnd.3) to mimic ischemia/reperfusion injury in vitro. P-gp-specific siRNA and pharmacological inhibitor cyclosporine A were used to inhibit P-gp, whereas pcDNA3.1 was utilized to overexpress P-gp. Twenty-four hours after reperfusion, acute ischemic stroke outcome, BBB integrity and permeability, autophagic proteins and relative signaling pathways were evaluated. P-gp levels were markedly elevated in mouse brain and endothelial cells following MCAO/R and OGD/R, respectively. P-gp siRNA silencing or pharmacologically inhibiting (cyclosporine A) reduced infarct volume and brain edema, attenuated brain pathology, and improved neurological behavior in association with attenuated accumulation of neutrophils and macrophages, reduced expression levels of inflammatory cytokines (TNF-α and IL-1ß), matrix metalloproteinases (MMP-2 and MMP-9) and adhesion molecules (ICAM-1 and VCAM-1). P-gp silence also counteracted BBB leakage, restored the expressions of tight junction proteins (Claudin-5, Occludin and ZO-1), activated autophagic proteins (upregulated LC3-II/LC3-I and Beclin 1, and downregulated P62), and diminished Akt/mTOR signal activity in mice following MCAO/R. In the endothelial cell OGD/R assay, P-gp silence downregulated the expressions of inflammatory cytokines and adhesion molecules, inhibited leukocytes adhesion and migration, increased tight junction protein levels, and activated autophagy, all were reversible by forceful P-gp expression. Additionally, treatment with an autophagy inhibitor (3-methyladenine) abolished protections against ischemic stroke and tight junction proteins reduction followed by P-gp silence. In conclusion, increased P-gp expression after ischemic injury resulted in BBB dysfunction and hyperpermeability by suppressing Akt/mTOR-induced endothelial autophagy.

Oxidative Stress and Antioxidative Therapy in Pulmonary Arterial Hypertension.

Pulmonary arterial hypertension (PAH) is clinically characterized by a progressive increase in pulmonary artery pressure, followed by right ventricular hypertrophy and subsequently right heart failure. The underlying mechanism of PAH includes endothelial dysfunction and intimal smooth muscle proliferation. Numerous studies have shown that oxidative stress is critical in the pathophysiology of PAH and involves changes in reactive oxygen species (ROS), reactive nitrogen (RNS), and nitric oxide (NO) signaling pathways. Disrupted ROS and NO signaling pathways cause the proliferation of pulmonary arterial endothelial cells (PAECs) and pulmonary vascular smooth muscle cells (PASMCs), resulting in DNA damage, metabolic abnormalities, and vascular remodeling. Antioxidant treatment has become a main area of research for the treatment of PAH. This review mainly introduces oxidative stress in the pathogenesis of PAH and antioxidative therapies and explains why targeting oxidative stress is a valid strategy for PAH treatment.

Long Non-coding RNAs (lncRNAs), A New Target in Stroke.

Stroke has become the most disabling and the second most fatal disease in the world. It has been a top priority to reveal the pathophysiology of stroke at cellular and molecular levels. A large number of long non-coding RNAs (lncRNAs) are identified to be abnormally expressed after stroke. Here, we summarize 35 lncRNAs associated with stroke, and clarify their functions on the prognosis through signal transduction and predictive values as biomarkers. Changes in the expression of these lncRNAs mediate a wide range of pathological processes in stroke, including apoptosis, inflammation, angiogenesis, and autophagy. Based on the exploration of the functions and mechanisms of lncRNAs in stroke, more timely, accurate predictions and more effective, safer treatments for stroke could be developed.

Research progress of mechanisms for tight junction damage on blood-brain barrier inflammation.

Inflammation in the central nervous system (CNS) contributes to disease pathologies by disrupting the integrity of the blood-brain barrier (BBB). Tight junctions (TJ) are a key component of the BBB. Following hypoxic-ischaemic or mechanical injury to the brain, inflammatory mediators are released such as cytokines, chemokines, and growth factors. Simultaneously, matrix metalloproteinases (MMPs) are released which can degrade TJ proteins. Subsequently, the function and morphology of the BBB are disrupted, which allows immune cells an opportunity to enter into the brain parenchyma. This review summarises the information on the role of TJ protein families in the BBB and provides a comprehensive summary of the mechanisms whereby inflammation breaks down the BBB by increasing degradation of TJ proteins.

Improvement of tube formation model of cell: Application for acute hypoxia in in vitro study of angiogenesis.

Angiogenesis caused by acute vascular occlusion occurs in various ischemic diseases. The in vitro tube formation assay by endothelial cells is a rapid, quantitative method for drug discovery on angiogenesis. Tube formation assay on Matrigel has been widely used to identify the angiogenesis, however, there are some problems to limit its application. In this study, we found for the first time that sodium dithionite (SD) could induce endothelial cell tube formation without Matrigel under hypoxia condition. To further verify our findings, the angiogenesis related proteins and mRNA at different time points after tube formation were measured both in primary human large-vessel endothelial cell (HUVECs) and murine microvascular endothelial cell line (Bend.3). In conclusion, compared with traditional tube formation on Matrigel, the novel model exhibits the following advantages: (1) Combination oxygen glucose deprivation with sodium dithionite (OGD-SD) model is operated more easily than traditional tube formation. (2) OGD-SD can be used for not only cell imaging, but also immunofluorescence, protein extraction and gene analysis. (3) OGD-SD is more applicable to acute hypoxia model of endothelial cell in vitro. (4) OGD-SD may be more suitable to identify molecular mechanism of compound that intervenes processes of pro-tube formation, tube formation and tube disconnection.

Vincristine-Induced Peripheral Neuropathy in Childhood Acute Lymphoblastic Leukemia: Genetic Variation as a Potential Risk Factor.

Vincristine (VCR) is the first-line chemotherapeutic medication often co-administered with other drugs to treat childhood acute lymphoblastic leukemia. Dose-dependent neurotoxicity is the main factor restricting VCR's clinical application. VCR-induced peripheral neuropathy (VIPN) sometimes results in dose reduction or omission, leading to clinical complications or affecting the patient's quality of life. With regard to the genetic basis of drug responses, preemptive pharmacogenomic testing and simultaneous blood level monitoring could be helpful for the transformation of various findings into individualized therapies. In this review, we discussed the potential associations between genetic variants in genes contributing to the pharmacokinetics/pharmacodynamics of VCR and VIPN incidence and severity in patients with acute lymphoblastic leukemia. Of note, genetic variants in the CEP72 gene have great potential to be translated into clinical practice. Such a genetic biomarker may help clinicians diagnose VIPN earlier. Besides, genetic variants in other genes, such as CYP3A5, ABCB1, ABCC1, ABCC2, TTPA, ACTG1, CAPG, SYNE2, SLC5A7, COCH, and MRPL47, have been reported to be associated with the VIPN, but more evidence is needed to validate the findings in the future. In fact, a variety of complex factors jointly determine the VIPN. In implementing precision medicine, the combination of genetic, environmental, and personal variables, along with therapeutic drug monitoring, will allow for a better understanding of the mechanisms of VIPN, improving the effectiveness of VCR treatment, reducing adverse reactions, and improving patients' quality of life.

PAF Receptor Inhibition Attenuates Neuronal Pyroptosis in Cerebral Ischemia/Reperfusion Injury.

Ischemic stroke is an inflammation-related disease, during which process activation of NLRP3 inflammasome and subsequent pyroptosis play crucial roles. Platelet-activating factor (PAF) is a potent phospholipid regulator of inflammation which exerts its effect via binding specific PAF receptor (PAFR). However, whether PAFR contributes to pyroptosis during ischemia/reperfusion (I/R) injury remains to be elucidated. To explore the underlying effect of PAFR on ischemic stroke from the perspective of pyroptosis, mice were subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) injury and primary cultures of mice cerebral cortical neurons were exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) injury to mimic I/R in vivo and in vitro, after which indexes associated with pyroptosis were analyzed. Intriguingly, our results indicated that inhibition of PAFR with its inhibitor XQ-1H or PAFR siRNA exerted a neuroprotective effect against I/R injury both in vivo and in vitro. Furthermore, inflammasome activation and pyroptosis after ischemic challenge were attenuated by XQ-1H or PAFR siRNA. Besides, the protection of XQ-1H was abolished by PAF stimulaiton to some extent. Moreover, XQ-1H or PAFR siRNA alleviated the neuronal pyroptosis induced by LPS and nigericin (an NLRP3 activator) in cortical neurons. Taken together, this study firstly demonstrates that PAFR is involved in neuronal pyroptosis after I/R injury, and XQ-1H, a specific PAFR inhibitor, has a promising prospect in attenuating I/R injury from the perspective of anti-pyroptosis.

10-O-(N N-Dimethylaminoethyl)-Ginkgolide B Methane-Sulfonate (XQ-1H) Ameliorates Cerebral Ischemia Via Suppressing Neuronal Apoptosis.

OBJECTIVES: The 10-O-(N N-dimethylaminoethyl)-ginkgolide B methane-sulfonate (XQ-1H) is an effective novel drug for the treatment of ischemic cerebrovascular disease derived from Ginkgolide B, a traditional Chinese medicine, has been widely used in the treatment of cardiovascular and cerebrovascular diseases. However, whether XQ-1H exerts neuroprotective effect via regulating neuronal apoptosis and the underlying mechanism remain to be elucidated. MATERIALS AND METHODS: This study was aimed to investigate the neuroprotective effect of XQ-1H in rats subjected to middle cerebral artery occlusion/reperfusion (MCAO/R) and the oxygen glucose deprivation/reoxygenation (OGD/R) induced neuronal apoptosis on pheochromocytoma (PC-12) cells. RESULTS: The results showed that administration of XQ-1H at different dosage (7.8, 15.6, 31.2 mg/kg) reduced the brain infarct and edema, attenuated the neuro-behavioral dysfunction, and improved cell morphology in brain tissue after MCAO/R in rats. Moreover, incubation with XQ-1H (1 µM, 3 µM, 10 µM, 50 µM, 100 µM) could increase the cell viability, and showed no toxic effect to PC-12 cells. XQ-1H at following 1 µM, 10 µM, 100 µM decreased the lactate dehydrogenase (LDH) activity and suppressed the cell apoptosis in PC-12 cells exposed to OGD/R. In addition, XQ-1H treatment could significantly inhibit caspase-3 activation both in vivo and in vitro, reciprocally modulate the expression of apoptosis related proteins, bcl-2, and bax via activating PI3K/Akt signaling pathway. For mechanism verification, LY294002, the inhibitor of PI3K/Akt pathway was introduced the expressions of bcl-2 and phosphorylated Akt were down-regulated, the expression of bax was up-regulated, indicating that XQ-1H could alleviate the cell apoptosis through activating the PI3K/Akt pathway. CONCLUSIONS: Our findings demonstrated that XQ-1H treatment could provide a neuroprotective effect against ischemic stroke induced by cerebral ischemia/reperfusion injury in vivo and in vitro through regulating neuronal survival and inhibiting apoptosis. The findings of the study confirmed that XQ-1H could be develop as a potential drug for treatment of cerebral ischemic stroke.

Dose tailoring of tacrolimus based on a non-linear pharmacokinetic model in children with refractory nephrotic syndrome.

The population pharmacokinetics (PPK) of tacrolimus (TAC) in children with refractory nephrotic syndrome (RNS) have not been well-characterized. This study aimed to investigate the significant factors affecting the TAC PPK characteristics of children with RNS and to optimize the dosing regimen. A total of 494 concentrations from 108 children were obtained from routine therapeutic drug monitoring between 2016 and 2018. Information regarding the demographic features, laboratory test results, genetic polymorphisms of CYP3A5 (rs776746) and co-therapy medications were collected. PPK analysis was performed using the nonlinear mixed-effects modelling (NONMEM) software and two modelling strategies (the linear one-compartment model and nonlinear Michaelis-Menten model) were evaluated and compared. CYP3A5 genotype, weight, daily dose of TAC and daily dose of diltiazem were retained in the final linear model. The absorption rate constant (Ka) was set at 4.48 h-1 in the linear model, and the apparent clearance (CL/F) and volume of distribution (V/F) in the final linear model were 14.2 L/h and 172 L, respectively. CYP3A5 genotype, weight and daily dose of diltiazem were the significant factors retained in the final nonlinear model. The maximal dose rate (Vmax) and the average steady-state concentration at half-Vmax (Km) in the final nonlinear model were 2.15 mg/day and 0.845 ng/ml, respectively. The nonlinear model described the pharmacokinetic data of TAC better than the linear model in children with RNS. A dosing regimen was proposed based on weight, CYP3A5 genotype and daily dose of diltiazem according to the final nonlinear PK model, which may facilitate individualized drug therapy with TAC.

Pyroptosis in stroke-new insights into disease mechanisms and therapeutic strategies.

Stroke is a common disease with high mortality and disability worldwide. Different forms of cell deaths, including apoptosis and necrosis, occur in ischemic or hemorrhagic brain tissue, among which pyroptosis, a newly discovered inflammation-related programmed cell death, is generally divided into two main pathways, the canonical inflammasome pathway and the non-canonical inflammasome pathway. Caspase-mediated pyroptosis requires the assembly of inflammasomes such as NLRP3, which leads to the release of inflammatory cytokines IL-1ß and IL-18 through the pores formed in the plasma membrane by GSDMD followed by neuroinflammation. Recently, pyroptosis and its relationship with inflammation have attracted more and more attention in the study of cerebral ischemia or hemorrhage. In addition, many inhibitors of pyroptosis targeting caspase, NLRP3, and the upstream pathway have been found to reduce brain tissue damage after stroke. In this review, we mainly introduce the pathology of stroke, the molecular mechanism, and process of pyroptosis, as well as the pivotal roles of pyroptosis in stroke, in order to provide new insights for the treatment of stroke.

XQ-1H promotes cerebral angiogenesis via activating PI3K/Akt/GSK3ß/ß-catenin/VEGF signal in mice exposed to cerebral ischemic injury.

Stroke still ranks as a most lethal disease worldwide. Angiogenesis during the chronic phase of ischemic stroke can alleviate ischemic injury and attenuate neurological deficit. XQ-1H is a new compound derived from the structure modification of ginkgolide B, which exerts anti-inflammation and neuroprotection against cerebral ischemic injury during the acute or subacute phase. However, whether XQ-1H facilitates angiogenesis and neural functional recovery during the chronic phase remains unclear. This research was designed to explore whether XQ-1H promotes angiogenesis after ischemic stroke and to preliminarily elucidate the mechanism. In vitro, XQ-1H was found to facilitate proliferation, migration and tube formation in bEnd.3 cells. In vivo, XQ-1H raised the CD31 positive microvessel number and increased focal cerebral blood flow in mice exposed to cerebral ischemic injury, and improved the neurological function. Mechanism studies revealed that XQ-1H exerted angiogenesis promoting effect via the PI3K/Akt/GSK3ß/ß-catenin/VEGF signal pathway, which was reversed by LY294002 (the specific inhibitor of PI3K/Akt). In conclusion, XQ-1H exerts angiogenetic effect both in vivo and in vitro, which is a potential agent against ischemic stroke during chronic phase.

Pretreatment of Indobufen and Aspirin and their Combinations with Clopidogrel or Ticagrelor Alleviates Inflammasome Mediated Pyroptosis Via Inhibiting NF-κB/NLRP3 Pathway in Ischemic Stroke.

Increasing studies showed that several anti-platelet drugs turned out to be a promising strategy for inflammatory response. In this study, we investigated the protective efficiency of pretreatment of indobufen or aspirin combined with clopidogrel or ticagrelor (IACT) on cerebral ischemic injury via NF-κB/NLRP3 pathway. Ischemia/reperfusion (I/R) injury was simulated in vivo by middle cerebral artery occlusion/reperfusion (MCAO/R) model, and rats were pretreated with indobufen and aspirin and their combinations with clopidogrel or ticagrelor respectively. The platelet aggregation, cerebral infarct size, water content, neurological impairment and LDH release were measured. The relative expression of inflammasome mediated pyroptosis was determined by ELISA, RT-PCR, Tunel, Immunofluorescence and Western blotting as appropriate. In vitro, I/R injury was simulated in PC12 cells using oxygen glucose deprivation/reperfusion (OGD/R) and Lipopolysaccharide (LPS) to induce pyroptosis. The effect of combinations were significantly greater than MCAO/R group on decreasing the platelet aggregation, infarct size, brain edema, LDH release and neurologic impairment. LPS aggravated I/R-induced PC12 cell injury, which was significantly suppressed by pretreatment of IACT and Bay11-7082. Mechanistically, IACT alleviated transcriptionally encoded IL-1ß, IL-18 and NLRP3 via inhibiting nuclear transportation of NF-κB. Importantly, at protein level, NLRP3, Caspase-1, IL-18, IL-1ß and GSDMD were significantly decreased in combination groups both in vivo and vitro. IACT reduce inflammasome mediated pyroptosis in MCAO/R rats and OGD/R PC12 cells through inhibiting NF-κB/NLRP3 signaling pathway, which suggests that drug combination is a protective strategy with clinical potential against I/R-induced injury. Graphical abstract.

The Mechanism, Clinical Efficacy, Safety, and Dosage Regimen of Atomoxetine for ADHD Therapy in Children: A Narrative Review.

Atomoxetine, a selective norepinephrine (NE) reuptake inhibitor, was approved for attention deficit/hyperactivity disorder (ADHD) treatment in children, adolescents and adults. We searched the database PubMed/MEDLINE (2000 to October 1, 2021). Only publications in English were considered. Atomoxetine inhibits the presynaptic norepinephrine transporter (NET), preventing the reuptake of NE throughout the brain along with inhibiting the reuptake of dopamine in specific brain regions such as the prefrontal cortex (PFC). The novel mechanism of atomoxetine also includes several new brain imaging studies and animal model studies. It is mainly metabolized by the highly polymorphic drug metabolizing enzyme cytochrome P450 2D6 (CYP2D6). Atomoxetine is effective and generally well tolerated. ADHD is often accompanied by multiple comorbidities. A series of studies have been published suggesting that atomoxetine is effective in the treatment of ADHD symptoms for children with various types of comorbidity. In some cases, it is possible that atomoxetine may have a positive influence on the symptoms of comorbidities. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, and has a negligible risk of abuse or misuse. The latest guideline updated that clinical dose selection of atomoxetine was recommended based on both CYP2D6 genotype and the peak concentration. To have a more comprehensive understanding of atomoxetine, this review sets the focus on the mechanism, clinical efficacy and dosage regimen in detail, and also touches on those studies regarding adverse reactions of atomoxetine.

Targeting pyroptosis to regulate ischemic stroke injury: Molecular mechanisms and preclinical evidences.

Stroke is one of the leading causes of death worldwide with limited therapies. After ischemic stroke occurs, a robust sterile inflammatory response happens and lasts for days and determines neurological prognosis. Pyroptosis is an inflammatory programmed cell death characterized by cleavage of pore-forming proteins gasdermins as a result of activating caspases and inflammasomes. It has morphological characteristics of rapid plasma-membrane rupture and release of proinflammatory intracellular contents as well as cytokines. Recent researches implicate pyroptosis involvement in the pathogenesis of ischemic stroke and inhibition of pyroptosis attenuates ischemic brain injury. In this review, we discussed molecular mechanisms of pyroptosis, evidences for pyroptosis involvement in different kinds of the central nervous system cells, as well as potential inhibitors for intervention of pyroptosis. Based on the review, we hypothesize the feasibility of therapeutic strategies targeting pyroptosis in the context of ischemic stroke.