Regulation of CNS pathology by Serpina3n/SERPINA3: The knowns and the puzzles.

Neuroinflammation, blood-brain barrier (BBB) dysfunction, neuron and glia injury/death and myelin damage are common central nervous system (CNS) pathologies observed in various neurological diseases and injuries. Serine protease inhibitor (Serpin) clade A member 3n (Serpina3n), and its human orthologue SERPINA3, is an acute-phase inflammatory glycoprotein secreted primarily by the liver into the bloodstream in response to systemic inflammation. Clinically, SERPINA3 is dysregulated in brain cells, cerebrospinal fluid and plasma in various neurological conditions. Although it has been widely accepted that Serpina3n/SERPINA3 is a reliable biomarker of reactive astrocytes in diseased CNS, recent data have challenged this well-cited concept, suggesting instead that oligodendrocytes and neurons are the primary sources of Serpina3n/SERPINA3. The debate continues regarding whether Serpina3n/SERPINA3 induction represents a pathogenic or a protective mechanism. Here, we propose possible interpretations for previously controversial data and present perspectives regarding the potential role of Serpina3n/SERPINA3 in CNS pathologies, including demyelinating disorders where oligodendrocytes are the primary targets. We hypothesise that the 'good' or 'bad' aspects of Serpina3n/SERPINA3 depend on its cellular sources, its subcellular distribution (or mis-localisation) and/or disease/injury types. Furthermore, circulating Serpina3n/SERPINA3 may cross the BBB to impact CNS pathologies. Cell-specific genetic tools are critically important to tease out the potential roles of cell type-dependent Serpina3n in CNS diseases/injuries.

Systematic characterization of short intronic splicing-regulatory elements in SMN2 pre-mRNA.

Intronic splicing enhancers and silencers (ISEs and ISSs) are two groups of splicing-regulatory elements (SREs) that play critical roles in determining splice-site selection, particularly for alternatively spliced introns or exons. SREs are often short motifs; their mutation or dysregulation of their cognate proteins frequently causes aberrant splicing and results in disease. To date, however, knowledge about SRE sequences and how they regulate splicing remains limited. Here, using an SMN2 minigene, we generated a complete pentamer-sequence library that comprises all possible combinations of 5 nucleotides in intron 7, at a fixed site downstream of the 5' splice site. We systematically analyzed the effects of all 1023 mutant pentamers on exon 7 splicing, in comparison to the wild-type minigene, in HEK293 cells. Our data show that the majority of pentamers significantly affect exon 7 splicing: 584 of them are stimulatory and 230 are inhibitory. To identify actual SREs, we utilized a motif set enrichment analysis (MSEA), from which we identified groups of stimulatory and inhibitory SRE motifs. We experimentally validated several strong SREs in SMN1/2 and other minigene settings. Our results provide a valuable resource for understanding how short RNA sequences regulate splicing. Many novel SREs can be explored further to elucidate their mechanism of action.

Pathological Bergmann glia alterations and disrupted calcium dynamics in ataxic Canavan disease mice.

Canavan disease (CD) is a recessively inherited pediatric leukodystrophy resulting from inactivating mutations to the oligodendroglial enzyme aspartoacylase (ASPA). ASPA is responsible for hydrolyzing the amino acid derivative N-acetyl-L-aspartate (NAA), and without it, brain NAA concentrations increase by 50% or more. Infants and children with CD present with progressive cognitive and motor delays, cytotoxic edema, astroglial vacuolation, and prominent spongiform brain degeneration. ASPA-deficient CD mice (Aspanur7/nur7 ) present similarly with elevated NAA, widespread astroglial dysfunction, ataxia, and Purkinje cell (PC) dendritic atrophy. Bergmann glia (BG), radial astrocytes essential for cerebellar development, are intimately intertwined with PCs, where they regulate synapse stability, functionality, and plasticity. BG damage is common to many neurodegenerative conditions and frequently associated with PC dysfunction and ataxia. Here, we report that, in CD mice, BG exhibit significant morphological alterations, decreased structural associations with PCs, loss of synaptic support proteins, and altered calcium dynamics. We also find that BG dysfunction predates cerebellar vacuolation and PC damage in CD mice. Previously, we developed an antisense oligonucleotide (ASO) therapy targeting Nat8l (N-acetyltransferase-8-like, "Nat8l ASO") that inhibits the production of NAA and reverses ataxia and PC atrophy in CD mice. Here, we show that Nat8l ASO administration in adult CD mice also leads to BG repair. Furthermore, blocking astroglial uptake of NAA is neuroprotective in astroglia-neuron cocultures exposed to elevated NAA. Our findings suggest that restoration of BG structural and functional integrity could be a mechanism for PC regeneration and improved motor function.

The myosin II inhibitor, blebbistatin, ameliorates pulmonary endothelial barrier dysfunction in acute lung injury induced by LPS via NMMHC IIA/Wnt5a/ß-catenin pathway.

Acute lung injury (ALI) or its most advanced form, acute respiratory distress syndrome (ARDS), is a severe inflammatory pulmonary process triggered by varieties of pathophysiological factors, among which endothelial barrier disruption plays a critical role in the progression of ALI/ARDS. As an inhibitor of myosin II, blebbistatin inhibits endothelial barrier damage. This study aimed to investigate the effect of blebbistatin on lung endothelial barrier dysfunction in LPS induced acute lung injury and its potential mechanism. Mice were challenged with LPS (5 mg/kg) by intratracheal instillation for 6 h to disrupt the pulmonary endothelial barrier in the model group. Blebbistatin (5 mg/kg, ip) was administrated 1 h before LPS challenge. The results showed that blebbistatin could significantly attenuate LPS-induced lung injury and pulmonary endothelial barrier dysfunction. And we observed that blebbistatin inhibited the activation of NMMHC IIA/Wnt5a/ß-catenin pathway in pulmonary endothelium after LPS treatment. In murine lung vascular endothelial cells (MLECs) and human umbilical vein endothelial cells (HUVECs), we further confirmed that Blebbistatin (1 µmol/L) markedly ameliorated endothelial barrier dysfunction in MLECs and HUVECs by modulating NMMHC IIA/Wnt5a/ß-catenin pathway. Our data demonstrated that blebbistatin could inhibit the development of pulmonary endothelial barrier dysfunction and ALI via NMMHC IIA/Wnt5a/ß-catenin signaling pathway.

Endothelial Conditional Knockdown of NMMHC IIA (Nonmuscle Myosin Heavy Chain IIA) Attenuates Blood-Brain Barrier Damage During Ischemia-Reperfusion Injury.

BACKGROUND AND PURPOSE: In ischemic stroke, breakdown of the blood-brain barrier (BBB) aggravates brain damage. Endothelial detachment contributes to BBB disruption and neurovascular dysfunction, but its regulation in stroke has yet to be clarified. We investigated the function of NMMHC IIA (nonmuscle myosin heavy chain IIA) in the endothelium on BBB breakdown and its potential mechanisms. METHODS: Endothelial conditional knockdown NMMHC IIA (Myh9ECKD) was constructed in vivo and in vitro, and its role was explored in middle cerebral artery occlusion/reperfusion-injured mice and oxygen-glucose deprivation/reoxygenation-injured brain microvascular endothelial cells. The degree of brain injury was analyzed using staining (2,3,5-triphenyltetrazolium chloride, hematoxylin, and eosin) and electron microscopy. BBB breakdown was investigated with leakage of Evans Blue dye and expression of TJs (tight junctions) and MMP (matrix metallopeptidase)-2/9. Transcriptomics for enrichment analysis was adopted to explore the potential downstream signaling pathways of NMMHC IIA involved in middle cerebral artery occlusion/reperfusion-induced BBB dysfunction. RESULTS: NMMHC IIA expression was upregulated in endothelial cells after cerebral ischemia/reperfusion injury. Myh9ECKD mice exhibited improvement in endothelial barrier hyperpermeability and TJs integrity stimulated by cerebral ischemia/reperfusion. Blebbistatin (NMMHC II inhibitor) treatment exerted the same effect. Transcriptomics showed that NMMHC IIA was involved in regulating various BBB-related genomic changes in the middle cerebral artery occlusion/reperfusion model, and NMMHC IIA was confirmed to significantly modulate Hippo and peroxisome proliferator-activated receptor gamma/nuclear factor-kappa B signaling pathways, which are closely related to BBB damage. CONCLUSIONS: Our findings provide some new insights into how NMMHC IIA contributes to maintaining the integrity of the cerebral endothelial barrier. NMMHC IIA could be a potential therapeutic target for ischemic stroke.

Neuroprotective Effect of Matrine in Mouse Model of Vincristine-Induced Neuropathic Pain.

Chemotherapy drugs such as vincristine (VCR) can cause neuropathic pain, and there is still lack of ideal strategy to treat it. The current study was designed to investigate effect of matrine (MT) on VCR-induced neuropathic pain in animal model. VCR (75 µg/kg, i.p. for 10 consecutive days) was administered to induce painful neuropathy model in mice. MT (15, 30 and 60 mg/kg, i.p.) and pregabalin (10 mg/kg, i.p.) were administered for 11 consecutive days. Various tests were performed to assess the degree of pain at different days (1, 6, 11, 16, and 21). Von Frey hair, hot plate, cold-plate and paw pressure tests were conducted to assess the degree of mechanical allodynia, thermal hyperalgesia, cold allodynia and mechanical hyperalgesia in the hind paw respectively. The electrophysiological and histopathological changes were also analyzed. Furthermore, tissue malondialdehyde (MDA), total antioxidant capacity (T-AOC),superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total calcium (TCA), myeloperoxidase (MPO), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10) were measured to investigate possible involvement of MT in inflammation and oxidative stress. Administration of MT attenuated the VCR-induced behavioral alterations as well as electrophysiological and histopathological changes in a dose dependent manner. Further, MT also attenuated the VCR-induced oxidative stress (MDA, T-AOC, GSH-Px, SOD and TCA) and inflammation (MPO, TNF-α, IL-6 and IL-10). Taken together, MT ameliorated VCR-induced painful neuropathy, which might be attributed to neuroprotective effects by subsequent reduction in oxidative stress and anti-inflammatory actions.

Antinociceptive effects of gentiopicroside on neuropathic pain induced by chronic constriction injury in mice: a behavioral and electrophysiological study.

Gentiopicroside (Gent) is promising as an important protective secoiridoid compound against pain. The present study was designed to investigate whether administration of Gent would alleviate the expression of nociceptive behaviors and whether it would cause the relevant electrophysiological changes in a chronic constriction injury (CCI) model of neuropathic pain in mice. Gent was administered from the seventh day after surgery for 8 consecutive days. Behavioral parameters and sciatic functional index were assessed immediately before surgery and on days 7, 8, 10, 12, and 14 post-CCI, and electrophysiological activities of sciatic nerve were recorded immediately after the behavioral test on the last day. The present study has shown that administration of Gent (at a dose of 50 and 100 mg/kg) increased behavioral parameters from day 8 compared with the CCI-NS group. Electrophysiological data indicated that CCI caused a significant reduction in nerve conduction velocities in the sciatic nerves and the amplitudes of compound action potential, while Gent at a dose of 50 or 100 mg/kg caused a significant recovery of electrophysiological changes induced by CCI. Our data indicated that Gent has antinociceptive effects on neuropathic pain induced by CCI.

Dispensable regulation of brain development and myelination by Serpina3n.

Serine protease inhibitor clade A member 3n (Serpina3n) or its human orthologue SERPINA3 is a secretory glycoprotein expressed primarily in the liver and brain under homeostatic conditions and dysregulated in various CNS pathologies. Yet its cellular expression profile and physiological significance in postnatal development remain elusive. Here, we showed that Serpina3n protein is expressed predominantly in oligodendroglial lineage cells in the postnatal CNS and that oligodendrocytes (OLs) responded to oxidative injury by upregulating Serpina3n production and secretion. Using loss-of-function genetic tools, we found that Serpina3n conditional knockout (cKO) from Olig2-expressing cells did not affect motor and cognitive functions in mice. Serpina3n depletion in Olig2-expressing cells did not appear to interfere with oligodendrocyte differentiation and developmental myelination nor affect the population of other glial cells and neurons in vivo. In vitro primary cell culture showed that Serpina3n-sufficient and -deficient oligodendroglial progenitor cells (OPCs) differentiated into myelin gene-expressing OLs comparatively. Together, these data suggest that Serpina3n plays a minor role, if any, in regulating brain neural cell development and myelination under homeostatic conditions and raise interests in pursuing its functional significance in CNS diseases and injuries.

Control of OPC proliferation and repopulation by the intellectual disability gene PAK1 under homeostatic and demyelinating conditions.

Appropriate proliferation and repopulation of oligodendrocyte progenitor cells (OPCs) determine successful (re)myelination in homeostatic and demyelinating brains. Activating mutations in p21-activated kinase 1 (PAK1) cause intellectual disability, neurodevelopmental abnormality, and white matter anomaly in children. It remains unclear if and how PAK1 regulates oligodendroglial development. Here, we report that PAK1 controls proliferation and regeneration of OPCs. Unlike differentiating oligodendrocytes, OPCs display high PAK1 activity which maintains them in a proliferative state by modulating PDGFRa-mediated mitogenic signaling. PAK1-deficient or kinase-inhibited OPCs reduce their proliferation capacity and population expansion. Mice carrying OPC-specific PAK1 deletion or kinase inhibition are populated with fewer OPCs in the homeostatic and demyelinated CNS than control mice. Together, our findings suggest that kinase-activating PAK1 mutations stall OPCs in a progenitor state, impacting timely oligodendroglial differentiation in the CNS of affected children and that PAK1 is a potential molecular target for replenishing OPCs in demyelinating lesions.

Identification of Matrine as a Kirsten rats Arcomaviral oncogene homolog inhibitor alleviating chemotherapy-induced neuropathic pain.

BACKGROUND: Chemotherapy-induced peripheral neuropathy (CIPN) represents a prevailing and severe clinical concern, characterized by limited availability of clinically effective treatment strategies. Current evidence endorses matrine's potential as a neuroprotective and analgesic agent for CIPN. Nevertheless, the precise targets and mechanisms of action of matrine remain insufficiently explored, impeding comprehensive pharmacological investigation and clinical application. OBJECTIVE: This study endeavors to elucidate the analgesic and neuroprotective effects of matrine in mice with vincristine-induced neuropathic pain. A focal point is the identification of matrine's specific target and the underlying molecular mechanisms governing its analgesic and neuroprotective actions. METHODS: To discern matrine's analgesic effects in CIPN mice, we conducted behavioral experiments encompassing the Von Frey filament test and Hargreaves Test. Furthermore, we conducted electrophysiological and histopathological assessments involving HE staining, Nissl staining, and Fluoro-Jade B staining to evaluate matrine's effects on neuroprotection within dorsal root ganglia and the spinal cord of CIPN mice. Sequentially, thermal shift assay, GTP hydrolysis assay, and nucleotide exchange assay were executed to validate matrine's inhibitory effects on KRAS. Molecular docking and site-directed mutagenesis experiments were implemented to identify the precise binding pocket of matrine on KRAS. Lastly, matrine's inhibitory effects on downstream signaling pathways of KRAS were confirmed through experiments conducted at animal model. RESULTS: Matrine exhibited a notable increase in mechanical withdrawal threshold and thermal withdrawal latency in vincristine-treated mice. This compound substantially ameliorated the neurofunctional blockade associated with sensory and motor functions induced by vincristine. Moreover, matrine mitigated pathological damage within DRG and the L4-L5 spinal cord regions. The study's MST experiments indicated matrine's substantial elevation of KRAS's melting temperature. The GTP hydrolysis and nucleotide exchange assays revealed concentration-dependent inhibition of KRAS activity by matrine. Molecular docking provided insight into the binding mode of matrine with KRAS, while site-directed mutagenesis verified the specific binding site of matrine on KRAS. Lastly, matrine's inhibition of downstream Raf/Erk1/2 and PI3K/Akt/mTOR signaling pathways of KRAS was confirmed in VCR mice. CONCLUSION: Compared to previous studies, our research has identified matrine as a natural inhibitor of the elusive protein KRAS, often considered "undruggable." Furthermore, this study has revealed that matrine exerts its therapeutic effects on chemotherapy-induced peripheral neuropathy (CIPN) by inhibiting KRAS activation, subsequently suppressing downstream signaling pathways such as Raf/Erk1/2 and PI3K/Akt/mTOR. This investigation signifies the discovery of a novel target for matrine, thus expanding the potential scope of its involvement in KRAS-related biological functions and diseases. These findings hold the promise of providing a crucial experimental foundation for forthcoming drug development initiatives centered around matrine, thereby advancing the field of pharmaceutical research.

Investigation of the regulatory effects of synthesized antisense oligonucleotides on androgen receptor (AR) exon 3 splicing in prostate cancer cells.

The Androgen Receptor (AR) gene plays a key role in castration-resistant prostate cancer (CRPC). Controlling the progression of CRPC by inhibiting AR gene expression is one of the core directions for prostate cancer (Pca) drug development. A 23-amino acids retention, named exon 3a, into the DNA binding domain of the splice variant AR23 has been shown to prevent AR from entering the nucleus and restore the sensitivity of cancer cells to related therapies. In this study, we conducted a preliminary investigation of the splicing modulation of the AR gene in order to develop a splice-switching therapy for Pca by promoting exon 3a inclusion. Using mutagenesis-coupled RT-PCR with AR minigene and over-expression of certain splicing factors, we found that serine/arginine-rich (SR) proteins are key factors facilitating the recognition of the 3' splice site of exon 3a (L-3' SS), while the deletion or blocking of the polypyrimidine tract (PPT) region of the original 3' splice site of exon 3 (S-3' SS) could strongly enhance exon 3a splicing without affecting the function of any SR protein. Furthermore, we designed a series of antisense oligonucleotides (ASOs) to screen drug candidates, and ASOs targeting S-3' SS and its PPT region or the exonic region of exon 3 turned out to be most effective in rescuing exon 3a splicing. A dose-response test indicated ASO12 as the lead candidate drug significantly promoting the inclusion of exon 3a to more than 85%. MTT assay confirmed that the cell proliferation was significantly inhibited after ASO treatment. Our results provide the first glance to AR splicing regulation. With several promising therapeutic ASO candidates obtained here, further development of ASO drugs to treat CRPC is strongly encouraged.

Ruscogenin ameliorates dasatinib-induced intestinal barrier dysfunction via ErbB4/YAP and ROCK/MLC pathways.

Dasatinib is effective in the treatment of chronic and acute myeloid leukemia, which could cause the side effect of gastrointestinal bleeding by overdose or longtime use. Ruscogenin (RUS) from the traditional Chinese medicine Ophiopogon japonicas could protect endothelial microvascular barrier function. In this study, the therapeutic effect and underlying mechanisms of RUS were investigated on intestinal barrier dysfunction induced by dasatinib. Male C57BL/6 J mice were given three doses of dasatinib (70, 140, 210 mg/kg, ig) and RUS (3, 10, 30 µg/kg, ip) to explore the effect of dasatinib on intestinal barrier and the intervention of RUS. It was proved that dasatinib could reduce intestinal blood flow, inhibit phosphorylation of EGFR family member v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 4 (ErbB4)/YES-associated protein (YAP) and activation of Rho-associated coiled coil-containing protein kinase (ROCK)/phosphorylation of (myosin light chain) MLC. RUS could significantly increase intestinal blood flow, improve intestinal injury, reduce Evans blue leakage and serum content of FITC-dextran 4 kDa, and increase the expression of connexin (ZO-1, Occludin and VE-cadherin). Meanwhile, the in vitro effect of RUS (0.01, 0.1, 1 µM) on the dysfunction of the endothelial barrier was observed in dasatinib (150 nM)-pretreated HUVECs. The results showed that RUS suppressed dasatinib-induced the leakage of Evans blue, and degradation of F-actin and connexin. Furthermore, RUS could significantly increase the phosphorylation of ErbB4 at Tyr1284 site and YAP at Ser397 site, and inhibit ROCK expression and phosphorylation of MLC at Ser19 site in vivo and in vitro. In conclusion, the present research proved that RUS could suppress the side effects of dasatinib-induced intestinal barrier dysfunction by regulating ErbB4/YAP and ROCK/MLC pathways.

Ruscogenin alleviates LPS-triggered pulmonary endothelial barrier dysfunction through targeting NMMHC IIA to modulate TLR4 signaling.

Pulmonary endothelial barrier dysfunction is a hallmark of clinical pulmonary edema and contributes to the development of acute lung injury (ALI). Here we reported that ruscogenin (RUS), an effective steroidal sapogenin of Radix Ophiopogon japonicus, attenuated lipopolysaccharides (LPS)-induced pulmonary endothelial barrier disruption through mediating non-muscle myosin heavy chain IIA (NMMHC IIA)‒Toll-like receptor 4 (TLR4) interactions. By in vivo and in vitro experiments, we observed that RUS administration significantly ameliorated LPS-triggered pulmonary endothelial barrier dysfunction and ALI. Moreover, we identified that RUS directly targeted NMMHC IIA on its N-terminal and head domain by serial affinity chromatography, molecular docking, biolayer interferometry, and microscale thermophoresis analyses. Downregulation of endothelial NMMHC IIA expression in vivo and in vitro abolished the protective effect of RUS. It was also observed that NMMHC IIA was dissociated from TLR4 and then activating TLR4 downstream Src/vascular endothelial cadherin (VE-cadherin) signaling in pulmonary vascular endothelial cells after LPS treatment, which could be restored by RUS. Collectively, these findings provide pharmacological evidence showing that RUS attenuates LPS-induced pulmonary endothelial barrier dysfunction by inhibiting TLR4/Src/VE-cadherin pathway through targeting NMMHC IIA and mediating NMMHC IIA‒TLR4 interactions.

Erratum: Author correction to 'Ruscogenin alleviates LPS-triggered pulmonary endothelial barrier dysfunction through targeting NMMHC IIA to modulate TLR4 signaling' [Acta Pharmaceutica Sinica B 12 (2022) 1198-1212].

[This corrects the article DOI: 10.1016/j.apsb.2021.09.017.].

Metabolomic Profiling of Brain Protective Effect of Edaravone on Cerebral Ischemia-Reperfusion Injury in Mice.

Edaravone (EDA) injection has been extensively applied in clinics for treating stroke. Nevertheless, the metabolite signatures and underlying mechanisms associated with EDA remain unclear, which deserve further elucidation for improving the accurate usage of EDA. Ischemia stroke was simulated by intraluminal occlusion of the right middle cerebral artery for 1 h, followed by reperfusion for 24 h in mice. Brain infarct size, neurological deficits, and lactate dehydrogenase (LDH) levels were improved by EDA. Significantly differential metabolites were screened with untargeted metabolomics by cross-comparisons with pre- and posttreatment of EDA under cerebral ischemia/reperfusion (I/R) injury. The possibly involved pathways, such as valine, leucine, and isoleucine biosynthesis, and phenylalanine, taurine, and hypotaurine metabolisms, were enriched with differential metabolites and relevant regulatory enzymes, respectively. The network of differential metabolites was constructed for the integral exhibition of metabolic characteristics. Targeted analysis of taurine, an important metabolic marker, was performed for further validation. The level of taurine decreased in the MCAO/R group and increased in the EDA group. The inhibition of EDA on cerebral endothelial cell apoptosis was confirmed by TdT-mediated dUTP nick-end labeling (TUNEL) stain. Cysteine sulfinic acid decarboxylase (CSAD), the rate-limiting enzyme of taurine generation, significantly increased along with inhibiting endothelial cell apoptosis after treatment of EDA. Thus, CSAD, as the possible new therapeutic target of EDA, was selected and validated by Western blot and immunofluorescence. Together, this study provided the metabolite signatures and identified CSAD as an unrecognized therapeutic intervention for EDA in the treatment of ischemic stroke via inhibiting brain endothelial cell apoptosis.

YiQiFuMai lyophilized injection attenuates cerebral ischemic injury with inhibition of neuronal autophagy through intervention in the NMMHC IIA-actin-ATG9A interaction.

BACKGROUND: YiQiFuMai lyophilized injection (YQFM) is derived from a traditional Chinese medicine prescription termed Shengmai San.YQFM is clinically applied to the treatment of cardiovascular and cerebrovascular diseases. It has been found that critical components of YQFM affect non-muscle myosin heavy chain IIA (NMMHC IIA), but its regulation in the excessive autophagy and the underlying mechanism has yet to be clarified. PURPOSE: To evaluate whether YQFM has neuroprotective effects on cerebral ischemia/reperfusion-induced injury by inhibiting NMMHC IIA-actin-ATG9A interaction for autophagosome formation. METHODS: The neuroprotective effects of YQFM were investigated in vivo in mice with middle cerebral artery occlusion/reperfusion (MCAO/R) (n = 6) by detecting neurological deficits, infarct volume, and histopathological changes. The NMMHC IIA-actin-ATG9A interaction was determined using immunofluorescence co-localization, co-immunoprecipitation, and proximity ligation assay. Rat pheochromocytoma (PC12) cells subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) were used to mimic neurons in in vitro experiments. RESULTS: In MCAO/R model mice, YQFM (1.342 g/kg) attenuated brain ischemia/reperfusion-induced injury by regulating NMMHC IIA-actin-mediated ATG9A trafficking. YQFM (400 µg/ml) also exerted similar effects on OGD/R-induced PC12 cells. Furthermore, RNAi of NMMHC IIA weakened the NMMHC IIA-F-actin-dependent ATG9A trafficking and, therefore, attenuated the neuroprotective activities of YQFM in vitro. CONCLUSION: These findings demonstrated that YQFM exerted neuroprotective effects by regulating the NMMHC IIA-actin-ATG9A interaction for autophagosome formation. This evidence sheds new light on the potential mechanism of YQFM in the treatment of cerebral ischemia/reperfusion.

Ginsenoside Rb1 improves brain, lung, and intestinal barrier damage in middle cerebral artery occlusion/reperfusion (MCAO/R) micevia the PPARγ signaling pathway.

Ischemic stroke causes brain inflammation and multi-organ injury, which is closely associated with the peroxisome proliferator-activated receptor-gamma (PPARγ) signaling pathway. Recent studies have indicated that ginsenoside Rb1 (GRb1) can protect the integrity of the blood-brain barrier after stroke. In the current study, a mouse model of middle cerebral artery occlusion/reperfusion (MCAO/R) was established to determine whether GRb1 can ameliorate brain/lung/intestinal barrier damage via the PPARγ signaling pathway. Staining (2,3,5-triphenyltetrazolium chloride, hematoxylin, and eosin) and Doppler ultrasonography were employed to detect pathological changes. Endothelial breakdown was investigated with the leakage of Evans Blue dye and the expression of TJs (tight junctions) and AJs (adherent junctions). Western blot and immunofluorescence were used to determine the levels of cell junction proteins, PPARγ and NF-κB. Results showed that GRb1 significantly mitigated multi-organ injury and increased the expression of cerebral microvascular, pulmonary vascular, and intestinal epithelial connexins. In brain, lung, and intestinal tissues, GRb1 activated PPARγ, decreased the levels of phospho-NF-κB p65, and inhibited the production of proinflammatory cytokines, thereby maintaining barrier permeability. However, co-treatment with GRb1 and the PPARγ antagonist GW9662 reversed the barrier-protective effect of GRb1. These findings indicated that GRb1 can improve stroke-induced brain/lung/intestinal barrier damagevia the PPARγ pathway.

Schisandrol A Attenuates Myocardial Ischemia/Reperfusion-Induced Myocardial Apoptosis through Upregulation of 14-3-3θ.

Schisandrol A (SA), one of the most abundant bioactive lignans extracted from the Schisandra chinensis (Turcz.) Baill., has multiple pharmacological properties. However, the underlying mechanisms of SA in protection against myocardial ischemia/reperfusion (MI/R) injury remain obscure. The present experiment was performed to explore the cardioprotective effects of SA in MI/R injury and hypoxia/reoxygenation- (H/R-) induced cardiomyocyte injury and clarify the potential underlying mechanisms. SA treatment significantly improved MI/R injury as reflected by reduced myocardium infarct size, attenuated histological features, and ameliorated biochemical indicators. In the meantime, SA could profoundly ameliorate oxidative stress damage as evidenced by the higher glutathione peroxidase (GSH-Px) as well as lower malondialdehyde (MDA) and reactive oxygen species (ROS). Additionally, SA alleviated myocardial apoptosis as evidenced by a striking reduction of cleaved caspase-3 expression and increase of Bcl-2/Bax ratio. Further experiments demonstrated that SA had certain binding capability to the key functional protein 14-3-3θ. Mechanistically, SA prevented myocardial apoptosis through upregulating 14-3-3θ expression. Interestingly, siRNA against 14-3-3θ could promote apoptosis of cardiomyocytes, and H/R injury after knockdown of 14-3-3θ could further aggravate apoptosis, while overexpression of 14-3-3θ could significantly reduce apoptosis induced by H/R injury. Further, 14-3-3θ siRNA markedly weakened the antiapoptotic role of SA. Our results demonstrated that SA could exert apparent cardioprotection against MI/R injury and H/R injury, and potential mechanisms might be associated with inhibition of cardiomyocyte apoptosis at least partially through upregulation of 14-3-3θ.

Inhibiting YAP in Endothelial Cells From Entering the Nucleus Attenuates Blood-Brain Barrier Damage During Ischemia-Reperfusion Injury.

Blood-brain barrier (BBB) damage is a critical event in ischemic stroke, contributing to aggravated brain damage. Endothelial cell form a major component of the BBB, but its regulation in stroke has yet to be clarified. We investigated the function of Yes-associated protein 1 (YAP) in the endothelium on BBB breakdown during cerebral ischemia/reperfusion (I/R) injury. The effects of YAP on BBB dysfunction were explored in middle cerebral artery occlusion/reperfusion (MCAO/R)-injury model mice and using brain microvascular endothelial cells (BMEC) exposed to oxygen-glucose deprivation/reoxygenation (OGD/R) injury. The degree of brain injury was estimated using staining (2,3,5-Triphenyltetrazolium chloride, hematoxylin and eosin) and the detection of cerebral blood flow. BBB breakdown was investigated by examining the leakage of Evans Blue dye and evaluating the expression of tight junction (TJ)-associated proteins and matrix metallopeptidase (MMP) 2 and 9. YAP expression was up-regulated in the nucleus of BMEC after cerebral I/R injury. Verteporfin (YAP inhibitor) down-regulated YAP expression in the nucleus and improved BBB hyperpermeability and TJ integrity disruption stimulated by cerebral I/R. YAP-targeted small interfering RNA (siRNA) exerted the same effects in BMEC cells exposed to OGD/R injury. Our findings provide new insights into the contributions made by YAP to the maintenance of BBB integrity and highlight the potential for YAP to serve as a therapeutic target to modulate BBB integrity following ischemic stroke and related cerebrovascular diseases.

Recent advances of traditional Chinese medicine on the prevention and treatment of COVID-19.

Coronavirus disease-2019 (COVID-19) is a new highly infectious disease caused by a novel coronavirus. Recently, the number of new cases infected pneumonia in the world continues to increase, which has aroused great concern from the international community. At present, there are no small-molecule specific anti-viral drugs for the treatment. The high mortality rate seriously threatens human health. Traditional Chinese medicine (TCM) is a unique health resource in China. The combination of TCM and Western medicine has played a positive and important role in combating COVID-19 in China. In this review, through literature mining and analysis, it was found that TCM has the potential to prevent and treat the COVID-19. Then, the network pharmacological studies demonstrated that TCM played roles of anti-virus, anti-inflammation and immunoregulation in the management of COVID-19 via multiple components acting on multiple targets and multiple pathways. Finally, clinical researches also confirmed the beneficial effects of TCM on the treatment of patients. This review may provide meaningful and useful information on further drug development of COVID-19 and other viral infectious diseases.