Strophanthidin Induces Apoptosis of Human Lung Adenocarcinoma Cells by Promoting TRAIL-DR5 Signaling.

Strophanthidin (SPTD), one of the cardiac glycosides, is refined from traditional Chinese medicines such as Semen Lepidii and Antiaris toxicaria, and was initially used for the treatment of heart failure disease in clinic. Recently, SPTD has been shown to be a potential anticancer agent, but the underlying mechanism of action is poorly understood. Herein, we explored the molecular mechanism by which SPTD exerts anticancer effects in A549 human lung adenocarcinoma cells by means of mass spectrometry-based quantitative proteomics in combination with bioinformatics analysis. We revealed that SPTD promoted the expression of tumor necrosis factor (TNF)-related apoptosis-inducing ligand receptor 2 (TRAIL-R2, or DR5) in A549 cells to activate caspase 3/6/8, in particular caspase 3. Consequently, the activated caspases elevated the expression level of apoptotic chromatin condensation inducer in the nucleus (ACIN1) and prelamin-A/C (LMNA), ultimately inducing apoptosis via cooperation with the SPTD-induced overexpressed barrier-to-autointegration factor 1 (Banf1). Moreover, the SPTD-induced DEPs interacted with each other to downregulate the p38 MAPK/ERK signaling, contributing to the SPTD inhibition of the growth of A549 cells. Additionally, the downregulation of collagen COL1A5 by SPTD was another anticancer benefit of SPTD through the modulation of the cell microenvironment.

A Photoactivated Ru (II) Polypyridine Complex Induced Oncotic Necrosis of A549 Cells by Activating Oxidative Phosphorylation and Inhibiting DNA Synthesis as Revealed by Quantitative Proteomics.

The ruthenium polypyridine complex [Ru(dppa)2(pytp)] (PF6)2 (termed as ZQX-1), where dppa = 4,7-diphenyl-1,10-phenanthroline and pytp = 4'-pyrene-2,2':6',2''-terpyridine, has been shown a high and selective cytotoxicity to hypoxic and cisplatin-resistant cancer cells either under irradiation with blue light or upon two-photon excitation. The IC50 values of ZQX-1 towards A549 cancer cells and HEK293 health cells are 0.16 ± 0.09 µM and >100 µM under irradiation at 420 nm, respectively. However, the mechanism of action of ZQX-1 remains unclear. In this work, using the quantitative proteomics method we identified 84 differentially expressed proteins (DEPs) with |fold-change| ≥ 1.2 in A549 cancer cells exposed to ZQX-1 under irradiation at 420 nm. Bioinformatics analysis of the DEPs revealed that photoactivated ZQX-1 generated reactive oxygen species (ROS) to activate oxidative phosphorylation signaling to overproduce ATP; it also released ROS and pyrene derivative to damage DNA and arrest A549 cells at S-phase, which synergistically led to oncotic necrosis and apoptosis of A549 cells to deplete excess ATP, evidenced by the elevated level of PRAP1 and cleaved capase-3. Moreover, the DNA damage inhibited the expression of DNA repair-related proteins, such as RBX1 and GPS1, enhancing photocytotoxicity of ZQX-1, which was reflected in the inhibition of integrin signaling and disruption of ribosome assembly. Importantly, the photoactivated ZQX-1 was shown to activate hypoxia-inducible factor 1A (HIF1A) survival signaling, implying that combining use of ZQX-1 with HIF1A signaling inhibitors may further promote the photocytotoxicity of the prodrug.

TrkB agonistic antibodies superior to BDNF: Utility in treating motoneuron degeneration.

While Brain-derived Neurotrophic Factor (BDNF) has long been implicated in treating neurological diseases, recombinant BDNF protein has failed in multiple clinical trials. In addition to its unstable and adhesive nature, BDNF can activate p75NTR, a receptor mediating cellular functions opposite to those of TrkB. We have now identified TrkB agonistic antibodies (TrkB-agoAbs) with several properties superior to BDNF: They exhibit blood half-life of days instead of hours, diffuse centimeters in neural tissues instead millimeters, and bind and activate TrkB, but not p75NTR. In addition, TrkB-agoAbs elicit much longer TrkB activation, reduced TrkB internalization and less intracellular degradation, compared with BDNF. More importantly, some of these TrkB-agoAbs bind TrkB epitopes distinct from that by BDNF, and work cooperatively with endogenous BDNF. Unlike BDNF, the TrkB-agoAbs exhibit a half-life of days/weeks and diffused readily in nerve tissues. We tested one of TrkB-agoAbs further and showed that it enhanced motoneuron survival in the spinal-root avulsion model for motoneuron degeneration in vivo. Thus, TrkB-agoAbs are promising drug candidates for the treatment of neural injury.

Tumor necrosis factor receptor-associated factor 6 participates in early brain injury after subarachnoid hemorrhage in rats through inhibiting autophagy and promoting oxidative stress.

Tumor necrosis factor receptor-associated factor 6 (TRAF6) is a member of the TRAF family and an important multifunctional intracellular adaptin of the tumor necrosis factor superfamily and toll/IL-1 receptor (TIR) superfamily. TRAF6 has been studied in several central nervous system diseases, including ischemic stroke, traumatic brain injury, and neurodegenerative diseases, but its role in subarachnoid hemorrhage (SAH) has not been fully illustrated. This study was designed to explore changes of expression level and potential roles and mechanisms of TRAF6 in early brain injury (EBI) after SAH using a Sprague-Dawley rat model of SAH induced in 0.3 mL non-heparinized autologous arterial blood injected into the pre-chiasmatic cistern. First, compared with the sham group, we found that the expression levels of TRAF6 increased gradually and peaked at 24 h after SAH. Second, the results showed that application of TRAF6 over-expression plasmid and genetic silencing siRNA could increase or decrease expression of TRAF6, respectively, and severely exacerbate or relieve EBI after SAH, including neuronal death, brain edema, and blood-brain barrier injury. Meanwhile, the levels of autophagy and oxidative stress were reduced and increased separately. Finally, GFP-TRAF6-C70A, which is a TRAF6 mutant that lacks E3 ubiquitin ligase activity, was used to explore the mechanism of TRAF6 in SAH, and the results showed that EBI and oxidative stress were reduced, but the levels of autophagy were increased under this condition. Collectively, these results indicated that TRAF6 affected the degree of EBI after SAH by inhibiting autophagy and promoting oxidative stress.

P2X7 Participates in Intracerebral Hemorrhage-Induced Secondary Brain Injury in Rats via MAPKs Signaling Pathways.

This study aimed to study the role of P2X7 in intracerebral hemorrhage (ICH)-induced secondary brain injury (SBI) and the underlying mechanisms. An autologous blood injection was used to induce ICH model in Sprague-Dawley rats, and cultured primary rat cortical neurons were exposed to oxyhemoglobin to mimic ICH in vitro. siRNA interference and over-expression of P2X7, agonists and antagonists of P2X7, p38 MAPK and ERK were exploited. The protein levels were assessed using Western blotting and immunofluorescence staining. Terminal deoxynucleotidyl transferase dUTP nick end labeling staining and Fluoro-Jade B were conducted to detect apoptotic and degenerating neurons. The protein levels of P2X7, phosphorylated p38, ERK, active caspase-3 and NF-κB were significantly increased by ICH, which could be further increased by BzATP (P2X7 agonist) and reduced by BBG (P2X7 antagonist). And BzATP demonstrated a significant increase in cell death ratio and brain water content, while BBG led to a reverse results. In addition, Over- P2X7 increased the levels of P2X7, phosphorylated p38, ERK, active caspase-3 and NF-κB, and aggravated cell apoptosis, while si P2X7 resulted in opposite effects. Finally, the protein levels of phosphorylated P38 and active caspase 3 were decreased by BzATP plus Hydrochloride (p38 MAPK antagonist) and increased vy BBG plus Asiatic acid (p38 MAPK agonist), while the protein levels of phosphorylated ERK and NF-κB were decreased with BzATP plus Nimbolide (ERK antagonist) and increased with BBG plus Saikosaponin C (ERK agonist). This study demonstrates that inhibition of P2X7 could prevent ICH-induced SBI via MAPKs signaling pathway.

Deep learning algorithm applied to plain CT images to identify superior mesenteric artery abnormalities.

OBJECTIVES: Atypical presentations, lack of biomarkers, and low sensitivity of plain CT can delay the diagnosis of superior mesenteric artery (SMA) abnormalities, resulting in poor clinical outcomes. Our study aims to develop a deep learning (DL) model for detecting SMA abnormalities in plain CT and evaluate its performance in comparison with a clinical model and radiologist assessment. MATERIALS AND METHODS: A total of 1048 patients comprised the internal (474 patients with SMA abnormalities, 474 controls) and external testing (50 patients with SMA abnormalities, 50 controls) cohorts. The internal cohort was divided into the training cohort (n = 776), validation cohort (n = 86), and internal testing cohort (n = 86). A total of 5 You Only Look Once version 8 (YOLOv8)-based DL submodels were developed, and the performance of the optimal submodel was compared with that of a clinical model and of experienced radiologists. RESULTS: Of the submodels, YOLOv8x had the best performance. The area under the curve (AUC) of the YOLOv8x submodel was higher than that of the clinical model (internal test set: 0.990 vs 0.878, P =.002; external test set: 0.967 vs 0.912, P =.140) and that of all radiologists (P <.001). The YOLOv8x submodel, when compared with radiologist assessment, demonstrated higher sensitivity (internal test set: 100.0 % vs 70.7 %, P =.002; external test set: 96.0 % vs 68.8 %, P <.001) and specificity (internal test set: 90.7 % vs 66.0 %, P =.025; external test set: = 88.0 % vs 66.0 %, P <.001). CONCLUSION: Using plain CT images, YOLOv8x was able to efficiently identify cases of SMA abnormalities. This could potentially improve early diagnosis accuracy and thus improve clinical outcomes.

Bidirectional association between polycystic ovary syndrome and periodontal diseases.

Polycystic ovary syndrome (PCOS) and periodontal disease (PDD) share common risk factors. The bidirectional interaction between PCOS and PDD has been reported, but until now, the underlying molecular mechanisms remain unclear. Endocrine disorders including hyperandrogenism (HA) and insulin resistance (IR) in PCOS disturb the oral microbial composition and increase the abundance of periodontal pathogens. Additionally, PCOS has a detrimental effect on the periodontal supportive tissues, including gingiva, periodontal ligament, and alveolar bone. Systemic low-grade inflammation status, especially obesity, persistent immune imbalance, and oxidative stress induced by PCOS exacerbate the progression of PDD. Simultaneously, PDD might increase the risk of PCOS through disturbing the gut microbiota composition and inducing low-grade inflammation and oxidative stress. In addition, genetic or epigenetic predisposition and lower socioeconomic status are the common risk factors for both diseases. In this review, we will present the latest evidence of the bidirectional association between PCOS and PDD from epidemiological, mechanistic, and interventional studies. A deep understanding on their bidirectional association will be beneficial to provide novel strategies for the treatment of PCOS and PDD.

Enhanced microbial degradation mediated by pyrogenic carbon toward p-nitrophenol: Role of carbon structures and iron minerals.

Pyrogenic carbon (PC) including black carbons and engineered carbons can mediate the extracellular electron transfer to facilitate the biogeochemical reaction with organic pollutants. Yet, the role of carbon structures and iron minerals on PC-mediated microbial degradation is still lacking of understanding. Herein, we studied the electrochemical properties of PCs produced from varied feedstock with regards to the mediated degradation of p-nitrophenol (PNP) by Shewanella putrefaciens CN32 in anoxic system. Mediated degradation by PCs was enhanced by facilitating extracellular electron transfer through oxygenated group and graphitic structure. Graphitic crystallites improved the electron-accepting capacity (as suggested by ID/IG and EAC) and diminished the electrochemical impedance (as suggested by Rct), contributing to PNP degradation under the anoxic system. Furthermore, more interfacial adsorption was conducive to the mediated reduction by the graphitic structure on PCs of high-temperature. In the presence of iron minerals, both hematite and goethite significantly facilitated PC-mediated degradation, which could be ascribed to the enhancement of the electron-donating capacity of microorganism and the accumulation of the reductive-state PCs by the interaction with generated Fe(II). This work paves a feasible way to the technical design on the remediation of phenolic contaminants by PC-mediated microbial degradation in environment.

Prediction of myocardial ischemia in coronary heart disease patients using a CCTA-Based radiomic nomogram.

Objective: The present study aimed to predict myocardial ischemia in coronary heart disease (CHD) patients based on the radiologic features of coronary computed tomography angiography (CCTA) combined with clinical factors. Methods: The imaging and clinical data of 110 patients who underwent CCTA scan before DSA or FFR examination in Changzhou Second People's Hospital, Nanjing Medical University (90 patients), and The First Affiliated Hospital of Soochow University (20 patients) from March 2018 to January 2022 were retrospectively analyzed. According to the digital subtraction angiography (DSA) and fractional flow reserve (FFR) results, all patients were assigned to myocardial ischemia (n = 58) and normal myocardial blood supply (n = 52) groups. All patients were further categorized into training (n = 64) and internal validation (n = 26) sets at a ratio of 7:3, and the patients from second site were used as external validation. Clinical indicators of patients were collected, the left ventricular myocardium were segmented from CCTA images using CQK software, and the radiomics features were extracted using pyradiomics software. Independent prediction models and combined prediction models were established. The predictive performance of the model was assessed by calibration curve analysis, receiver operating characteristic (ROC) curve and decision curve analysis. Results: The combined model consisted of one important clinical factor and eight selected radiomic features. The area under the ROC curve (AUC) of radiomic model was 0.826 in training set, and 0.744 in the internal validation set. For the combined model, the AUCs were 0.873, 0.810, 0.800 in the training, internal validation, and external validation sets, respectively. The calibration curves demonstrated that the probability of myocardial ischemia predicted by the combined model was in good agreement with the observed values in both training and validation sets. The decision curve was within the threshold range of 0.1-1, and the clinical value of nomogram was higher than that of clinical model. Conclusion: The radiomic characteristics of CCTA combined with clinical factors have a good clinical value in predicting myocardial ischemia in CHD patients.

Development of neutralizing antibodies against SARS-CoV-2, using a high-throughput single-B-cell cloning method.

Background: Rapid and efficient strategies are needed to discover neutralizing antibodies (nAbs) from B cells derived from virus-infected patients. Methods: Here, we report a high-throughput single-B-cell cloning method for high-throughput isolation of nAbs targeting diverse epitopes on the SARS-CoV-2-RBD (receptor binding domain) from convalescent COVID-19 patients. This method is simple, fast and highly efficient in generating SARS-CoV-2-neutralizing antibodies from COVID-19 patients' B cells. Results: Using this method, we have developed multiple nAbs against distinct SARS-CoV-2-RBD epitopes. CryoEM and crystallography revealed precisely how they bind RBD. In live virus assay, these nAbs are effective in blocking viral entry to the host cells. Conclusion: This simple and efficient method may be useful in developing human therapeutic antibodies for other diseases and next pandemic.

Etesevimab in combination with JS026 neutralizing SARS-CoV-2 and its variants.

The neutralizing antibody is a potential therapeutic for the ongoing COVID-19 pandemic. As an antiviral agent, numerous mAbs recognize the epitopes that overlap with ACE2-binding sites in the SARS-CoV-2-RBD. Some studies have shown that residual changes on the spike protein can significantly decrease the efficiency of neutralizing antibodies. To address this issue, a therapeutic cocktail could be an effective countermeasure. In the present study, we isolated a fully human neutralizing antibody, JS026, from a convalescent patient. The comparative analysis revealed that JS026 binding to SARS-CoV-2-RBD mainly located between epitopes for class 2 and class 3 mAbs as opposed to that of class 1 (etesevimab) antibodies. A cocktail of etesevimab and JS026 increased neutralizing efficacy against both wild-type SARS-CoV-2 and the recent emergence of Alpha, Beta, Gamma, and Delta variants. JS026 and the cocktail reduced virus titers in the infected lungs of hACE2 transgenic mice and relieved pathological changes. These findings would benefit antibody-based therapeutic countermeasures in the treatment of COVID-19.

Cofilin 2 Acts as an Inflammatory Linker Between Chronic Periodontitis and Alzheimer's Disease in Amyloid Precursor Protein/Presenilin 1 Mice.

Increasing evidence has shown a correlation between chronic periodontitis (CP) and Alzheimer's disease (AD). Nevertheless, there is still a lack of direct evidence, and especially key molecules to connect the two diseases. This study aims to investigate potential protein links between CP and AD within the inflammatory aspect. The hippocampus of CP model mice and controls were collected, and changes in protein expression were evaluated using two-dimensional differential in-gel electrophoresis (2D-DIGE) analysis combined with liquid chromatography tandem mass spectrometry. A total of 15 differentially expressed proteins were identified in CP model mice, as compared with the controls. Among them, S100-A9, transthyretin, Cofilin 2, peroxiredoxin 2, and lipocalin-2 were validated by Western blot according to their dual function both in inflammation and AD. Based on 2D-DIGE analysis, CP animal model had higher levels of S100-A9, Cofilin 2, peroxiredoxin 2, and lipocalin-2 compared to controls. The level of Cofilin 2, one of the well-established proteins in the pathology of AD, was strongly correlated with the time course of CP pathology, indicating a specific molecular correlation between CP and AD. Moreover, the in vivo results showed the level of Cofilin 2 increased significantly along with a prominent increase of the phosphorylation of protein phosphatase 2 (PP2A) and tau protein in the cell lysates of Porphyromonas gingivalis (P.g-LPS)-treated SK-N-SH APPwt cells. Cofilin 2 inhibition resulted in a sharp decrease in PP2A dependent of tau phosphorylation. Furthermore, tumor growth factor (TGF)-ß1 was one of the most important inflammatory cytokines for the Pg-LPS-induced Cofilin 2 upregulation in SK-N-SH APPwt cells. These results showed inflammation served as the bond between CP and AD, whereas inflammatory related proteins could be the key linkers between the two diseases. Determining the association between CP and AD at the molecular mechanism will not only hold the direct evidence of the association between the two diseases but also provide a new way of preventing and treating AD: the effective prevention and treatment of CP could serve as a useful method to alleviate the development of AD.

DELLA-NAC Interactions Mediate GA Signaling to Promote Secondary Cell Wall Formation in Cotton Stem.

Gibberellins (GAs) promote secondary cell wall (SCW) development in plants, but the underlying molecular mechanism is still to be elucidated. Here, we employed a new system, the first internode of cotton, and the virus-induced gene silencing method to address this problem. We found that knocking down major DELLA genes via VIGS phenocopied GA treatment and significantly enhanced SCW formation in the xylem and phloem of cotton stems. Cotton DELLA proteins were found to interact with a wide range of SCW-related NAC proteins, and virus-induced gene silencing of these NAC genes inhibited SCW development with downregulated biosynthesis and deposition of lignin. The findings indicated a framework for the GA regulation of SCW formation; that is, the interactions between DELLA and NAC proteins mediated GA signaling to regulate SCW formation in cotton stems.

Humoral immune response to circulating SARS-CoV-2 variants elicited by inactivated and RBD-subunit vaccines.

SARS-CoV-2 variants could induce immune escape by mutations on the receptor-binding domain (RBD) and N-terminal domain (NTD). Here we report the humoral immune response to circulating SARS-CoV-2 variants, such as 501Y.V2 (B.1.351), of the plasma and neutralizing antibodies (NAbs) elicited by CoronaVac (inactivated vaccine), ZF2001 (RBD-subunit vaccine) and natural infection. Among 86 potent NAbs identified by high-throughput single-cell VDJ sequencing of peripheral blood mononuclear cells from vaccinees and convalescents, near half anti-RBD NAbs showed major neutralization reductions against the K417N/E484K/N501Y mutation combination, with E484K being the dominant cause. VH3-53/VH3-66 recurrent antibodies respond differently to RBD variants, and K417N compromises the majority of neutralizing activity through reduced polar contacts with complementarity determining regions. In contrast, the 242-244 deletion (242-244Δ) would abolish most neutralization activity of anti-NTD NAbs by interrupting the conformation of NTD antigenic supersite, indicating a much less diversity of anti-NTD NAbs than anti-RBD NAbs. Plasma of convalescents and CoronaVac vaccinees displayed comparable neutralization reductions against pseudo- and authentic 501Y.V2 variants, mainly caused by E484K/N501Y and 242-244Δ, with the effects being additive. Importantly, RBD-subunit vaccinees exhibit markedly higher tolerance to 501Y.V2 than convalescents, since the elicited anti-RBD NAbs display a high diversity and are unaffected by NTD mutations. Moreover, an extended gap between the third and second doses of ZF2001 leads to better neutralizing activity and tolerance to 501Y.V2 than the standard three-dose administration. Together, these results suggest that the deployment of RBD-vaccines, through a third-dose boost, may be ideal for combating SARS-CoV-2 variants when necessary, especially for those carrying mutations that disrupt the NTD supersite.

Roles of TRAF6 in Central Nervous System.

Tumor necrosis factor receptor-associated factor (TRAF) is an important binding protein of tumor necrosis factor (TNF) superfamily and the toll/IL-1 receptor (TIR) superfamily, which play an important role in innate immunity and acquired immunity. TRAFs family have 7 members (TRAF1-7), and TRAF6 has its special facture and biological function. TRAF6 has two special domains: C-terminal domain and N-terminal domain, which could integrate with multiple kinases and regulate signaling pathway function as an E3 ubiquitin ligase. Studies have increasingly found that TRAF6 is closely related to central nervous system diseases, such as stroke, Traumatic brain injury, neurodegenerative diseases and neuropathic pain. Further research on the pathophysiological mechanism may be expected to become the new targets for the treatment of central nervous system diseases.

Melatonin Alleviates Intracerebral Hemorrhage-Induced Secondary Brain Injury in Rats via Suppressing Apoptosis, Inflammation, Oxidative Stress, DNA Damage, and Mitochondria Injury.

Intracerebral hemorrhage (ICH) is a cerebrovascular disease with high mortality and morbidity, and the effective treatment is still lacking. We designed this study to investigate the therapeutic effects and mechanisms of melatonin on the secondary brain injury (SBI) after ICH. An in vivo ICH model was induced via autologous whole blood injection into the right basal ganglia in Sprague-Dawley (SD) rats. Primary rat cortical neurons were treated with oxygen hemoglobin (OxyHb) as an in vitro ICH model. The results of the in vivo study showed that melatonin alleviated severe brain edema and behavior disorders induced by ICH. Indicators of blood-brain barrier (BBB) integrity, DNA damage, inflammation, oxidative stress, apoptosis, and mitochondria damage showed a significant increase after ICH, while melatonin reduced their levels. Meanwhile, melatonin promoted further increasing of expression levels of antioxidant indicators induced by ICH. Microscopically, TUNEL and Nissl staining showed that melatonin reduced the numbers of ICH-induced apoptotic cells. Inflammation and DNA damage indicators exhibited an identical pattern compared to those above. Additionally, the in vitro study demonstrated that melatonin reduced the apoptotic neurons induced by OxyHb and protected the mitochondrial membrane potential. Collectively, our investigation showed that melatonin ameliorated ICH-induced SBI by impacting apoptosis, inflammation, oxidative stress, DNA damage, brain edema, and BBB damage and reducing mitochondrial membrane permeability transition pore opening, and melatonin may be a potential therapeutic agent of ICH.

HMGB1 promotes neurovascular remodeling via Rage in the late phase of subarachnoid hemorrhage.

High-mobility group box1 (HMGB1) is a nuclear protein widely expressed in the central nervous system. Extracellular HMGB1 serves as a proinflammatory cytokine and contributes to brain injury during the acute stage post-stroke. Recently, increasing evidence has demonstrated beneficial effects of HMGB1 in some types of brain injury, but little is known about its effects during the late phase of subarachnoid hemorrhage (SAH). This study was designed to explore the potential roles and mechanisms of HMGB1 and its receptor, receptor for advanced glycation end-products (Rage), on brain recovery in the late stage of experimental SAH. Two inhibitors of HMGB1, ethyl pyruvate and glycyrrhizin (EP and GA), and Rage antagonist FPS-ZM1 were used to determine whether HMGB1 promotes brain recovery after SAH. The administration of EP, GA, and FPS-ZM1 effectively reduced HMGB1 and Rage expression. Correspondingly, protein levels of beneficial growth factors (NGF, BDNF, and VEGF) and numbers of BrdU and DCX positive neurons in the cortex were also decreased. The biphasic roles of HMGB1 may be based on the different redox modifications of cysteine residues. In this research, rats injected with two different redox status HMGB1 showed different prognosises at 7-14day after SAH. Recombinant HMGB1 can promote cytokine stimulating activity and aggravate brain injury. However, oxidized HMGB1 was unable to stimulate TNF production but can promote brain recovery by promoting neurotrophin expression. In conclusion, our investigation identified that HMGB1 promotes neurovascular recovery via Rage and may act in the oxidized state in the late stage of SAH.

The role of hydrogen sulfide in stroke.

Stroke is a kind of acute cerebrovascular disease characterized by the focal lack of neurological function, including ischemic stroke and hemorrhagic stroke. As society ages rapidly, stroke has become the second leading cause of disability and death, and also become the main threat to human health and life. In recent years, findings from increasing animal and clinical trials have supplied scientific evidences for the treatment of stroke. Hydrogen sulfide (H2S), which has always been seen as a toxic gas, now has been thought to be the third gaseous signaling molecule following nitric oxide and carbon monoxide. Accumulating evidences indicate that H2S plays an important role in stroke. Given that its neuroprotective effect is dose-dependent, only when its concentration is relatively low, H2S can yield the neuroprotection, while high dose may lead to neurotoxicity. All these study results suggest that H2S may offer a new promising application for the therapy of stroke. Here, our review will present the role of H2S in stroke from its mechanism to animal and clinical studies.

The Role of Omega-3 Polyunsaturated Fatty Acids in Stroke.

Stroke is the third commonest cause of death following cardiovascular diseases and cancer. In particular, in recent years, the morbidity and mortality of stroke keep remarkable growing. However, stroke still captures people attention far less than cardiovascular diseases and cancer. Past studies have shown that oxidative stress and inflammation play crucial roles in the progress of cerebral injury induced by stroke. Evidence is accumulating that the dietary supplementation of fish oil exhibits beneficial effects on several diseases, such as cardiovascular diseases, metabolic diseases, and cancer. Omega-3 polyunsaturated fatty acids (n-3 PUFAs), the major component of fish oil, have been found against oxidative stress and inflammation in cardiovascular diseases. And the potential of n-3 PUFAs in stroke treatment is attracting more and more attention. In this review, we will review the effects of n-3 PUFAs on stroke and mainly focus on the antioxidant and anti-inflammatory effects of n-3 PUFAs.

Transient receptor potential channel 1/4 reduces subarachnoid hemorrhage-induced early brain injury in rats via calcineurin-mediated NMDAR and NFAT dephosphorylation.

Transient receptor potential channel 1/4 (TRPC1/4) are considered to be related to subarachnoid hemorrhage (SAH)-induced cerebral vasospasm. In this study, a SAH rat model was employed to study the roles of TRPC1/4 in the early brain injury (EBI) after SAH. Primary cultured hippocampal neurons were exposed to oxyhemoglobin to mimic SAH in vitro. The protein levels of TRPC1/4 increased and peaked at 5 days after SAH in rats. Inhibition of TRPC1/4 by SKF96365 aggravated SAH-induced EBI, such as cortical cell death (by TUNEL staining) and degenerating (by FJB staining). In addition, TRPC1/4 overexpression could increase calcineurin activity, while increased calcineurin activity could promote the dephosphorylation of N-methyl-D-aspartate receptor (NMDAR). Calcineurin antagonist FK506 could weaken the neuroprotection and the dephosphorylation of NMDAR induced by TRPC1/4 overexpression. Contrarily, calcineurin agonist chlorogenic acid inhibited SAH-induced EBI, even when siRNA intervention of TRPC1/4 was performed. Moreover, calcineurin also could lead to the nuclear transfer of nuclear factor of activated T cells (NFAT), which is a transcription factor promoting the expressions of TRPC1/4. TRPC1/4 could inhibit SAH-induced EBI by supressing the phosphorylation of NMDAR via calcineurin. TRPC1/4-induced calcineurin activation also could promote the nuclear transfer of NFAT, suggesting a positive feedback regulation of TRPC1/4 expressions.