Periplogenin inhibits pathologic synovial proliferation and infiltration in rheumatoid arthritis by regulating the JAK2/3-STAT3 pathway.

Rheumatoid arthritis (RA) is an autoimmune disease that affects joints, causing inflammation, synovitis, and erosion of cartilage and bone. Periplogenin is an active ingredient in the anti-rheumatic and anti-inflammatory herb, cortex periplocae. We conducted a study using a CIA model and an in vitro model of fibroblast-like synoviocytes (FLS) induced by Tumor Necrosis Factor-alpha (TNF-α) stimulation. We evaluated cell activity, proliferation, and migration using the CCK8 test, EDU kit, and transwell assays, as well as network pharmacokinetic analysis of periplogenin targets and RA-related effects. Furthermore, we measured inflammatory factors and matrix metalloproteinases (MMPs) expression using ELISA and qRT-PCR assays. We also evaluated joint destruction using HE and Safranin O-Fast Green Staining and examined the changes in the JAK2/3-STAT3 pathway using western blot. The results indicated that periplogenin can effectively inhibit the secretion of inflammatory factors, suppress the JAK2/3-STAT3 pathway, and impede the proliferation and migration of RA FLS. Thus, periplogenin alleviated the Synovial inflammatory infiltration of RA.

ß-asarone improves cognitive impairment and alleviates autophagy in mice with vascular dementia via the cAMP/PKA/CREB pathway.

BACKGROUND: Vascular dementia (VD) is the second most common type of dementia after Alzheimer's disease. ß-asarone, a major component of Acorus tatarinowii Schott, is important in neurodegenerative and neurovascular diseases. Studies have confirmed that ß-asarone can mitigate autophagy and reduce damage in hypoxic cells. We also reported that ß-asarone improves learning and memory. This study further clarifies whether ß-asarone attenuates cerebral ischaemic injury by acting through the cAMP/PKA/CREB pathway in VD model mice. METHODS: Here, genes and potential pathways that may be targeted by ß-asarone for the treatment of transient cerebral ischaemia (TCI) and cognitive impairment (CI) were obtained using network pharmacology. The two-vessel occlusion method was used to establish the VD model. The Morris water maze test was used to evaluate the effects on memory. Then, the protein levels of mitofusin-2 (Mfn2), brain-derived neurotrophic factor (BDNF), optic atrophy 1 (OPA1), cyclic adenosine monophosphate (cAMP), myelin basic protein (MBP), matrix metalloproteinase-9 (MMP9) and neuron specific enolase (NSE) were determined by ELISA. The levels of superoxide dismutase (SOD) and malonaldehyde (MDA) were measured using commercial kits. Then, qRT-PCR was employed to investigate the expression of the candidate genes screened from the protein-protein interaction (PPI) network. Furthermore, the expression of the autophagy-related proteins Beclin-1, (microtubule-associated protein light chain 3) LC3, p62, postsynaptic density protein 95 (PSD95), protein kinase A (PKA), pPKA, cyclic-AMP response binding protein (CREB), and pCREB was determined by western blotting. The expression of autophagy-related proteins, PSD95 and translocase of outer mitochondrial membrane 20 (TOM20) was determined by immunofluorescence analyses. RESULTS: The network pharmacological analysis showed 234 targets related to ß-asarone, 1,118 genes related to TCI and 2,039 genes associated with CI. Our results confirm that ß-asarone treatment not only alleviated brain damage in the VD model by improving mitochondrial and synaptic function, reducing neuronal injury and upregulating the expression of antioxidants but also effectively improved the cognitive behaviour of VD model mice. Moreover, ß-asarone downregulated VD-induced RELA and CCND1 mRNA expression. In addition, we validated that ß-asarone increased the phosphorylation of PKA and CREB and upregulated cAMP protein expression. The results showed that the cAMP/PKA/CREB signalling pathway was upregulated. Moreover, ß-asarone administration decreased the protein expression levels of Beclin-1 and LC3 and increased the expression levels of p62 in VD model mice. CONCLUSIONS: ß-asarone inhibits Beclin-1-dependent autophagy and upregulates the cAMP/PKA/CREB signalling pathway to attenuate mitochondrial and synaptic damage from cerebral ischaemia and improve learning and cognitive abilities in VD model mice.

[Mechanism of Zhongfeng Xingnao Decoction in improving microcirculatory disorders in cerebral hemorrhage based on network pharmacology and molecular docking techniques].

This study aimed to explore the mechanism of Zhongfeng Xingnao Decoction(ZFXN) in intervening microcirculatory di-sorders in cerebral hemorrhage by network pharmacology and molecular docking techniques. The information on the components of ZFXN was obtained through the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) database, and the predicted targets of chemical components were obtained from PubChem and SwissTargetPrediction. The relevant targets of cerebral hemorrhage and microcirculatory disorders were collected from the GeneCards database, and the common targets of the components and diseases were analyzed by the Database for Annotation, Visualization, and Integrated Discovery(DAVID) for Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analyses. Visualization of the correlation network was carried out using Cytoscape software to further screen important chemical components for molecular docking prediction with disease targets. The animal experiment validation was performed using modified neurological severity score(mNSS), enzyme-linked immunosorbent assay(ELISA), quantitative real-time polymerase chain reaction(qRT-PCR), immunofluorescence, and Western blot to detect the effects of ZFXN intervention in mice with cerebral hemorrhage. The results showed that there were 31 chemical components and 856 targets in the four drugs contained in ZFXN, 173 targets for microcirculatory disorders in cerebral hemorrhage, and 57 common targets for diseases and components. The enrichment analysis showed that common targets were mainly involved in biological processes, such as cell proliferation and apoptosis, and signaling pathways, such as tumor pathway, viral infection, phosphoinositide-3-kinase/protein kinase B(PI3K/AKT) signaling pathway, and mitogen-activated protein kinase(MAPK) signaling pathway. Molecular docking results revealed that the common components ß-sitosterol of Rhei Radix et Rhizoma, Notoginseng Radix et Rhizoma, and Ginseng Radix et Rhizoma Rubra showed good docking with proto-oncogene tyrosine-protein kinase(SRC), signal transducer and activator of transcription 3(STAT3), phosphoinositide-3-kinase catalytic alpha polypeptide gene(PIK3CA), recombinant protein tyrosine phosphatase non receptor type 11(PTPN11), AKT1, epidermal growth factor receptor(EGFR), calcium adhesion-associated protein beta 1(CTNNB1), vascular endothelial growth factor A(VEGFA), and tumor protein p53(TP53). Moreover, sennoside E of Rhei Radix et Rhizoma showed good docking with MAPK1. The results revealed that the ZFXN relieved the neural injury in mice with cerebral hemorrhage, decreased the expression of S100 calcium-binding protein B(S100ß), neuron specific enolase(NSE), matrix metalloproteinase 9(MMP9), tumor necrosis factor α(TNF-α), interleukin 1ß(IL-1ß), SRC, EGFR, CTNNB1, VEGFA, TP53, glial fibrillary acidic protein(GFAP), and leukocyte differentiation antigen 86(CD86), and increased the expression of p-PI3K, p-AKT, and zona occludens 1(ZO-1). The results indicate that ZFXN may inhibit neuronal apoptosis and inflammatory response through PI3K/AKT/p53 pathway to protect the blood-brain barrier, thereby slowing down microcirculatory impairment in cerebral hemorrhage.

Anti-inflammatory compounds from the rhizome of Acorus calamus var. angustatus Besser and their mechanism.

Seven compounds, named ß-sitosterol (1), daucosterol (2), (+)-pinoresinol-ß-D-glucoside (3), (-)-syringaresinol 4-O-ß-D-apiofuranosyl-(1→2)- ß-D-glucopyranoside (4), 4-hydroxybenzoic acid (5), 2-(3', 4'-dihydroxyphenyl)-1, 3-pepper ring-5-aldehyde (6) and spinosin (7) were isolated from the rhizome of Acorus calamus var. angustatus Besser. 3, 4, 6 and 7 were isolated from this medicinal plant for the first time. Structures were elucidated by physicochemical properties and extensive spectroscopic analysis, as well as by comparison with literature data. The anti-inflammatory activity and related mechanisms of the seven compounds showed that compounds 1-7 all increased the levels of GSH-PX and SOD and decreased the levels of MDA, TNF-α, IL-1ß and IL-6. Compound 4 showed the best effect of anti-inflammatory and Beclin-1 inhibition. These results suggest that compound 4 has stronger anti-inflammatory effect and provide preliminary evidence that the mechanism of action of compound 4 in attenuating LPS-induced inflammatory damage may be related to the inhibition of Beclin-1-dependent autophagy.

Scutellarin acts on the AR-NOX axis to remediate oxidative stress injury in a mouse model of cerebral ischemia/reperfusion injury.

BACKGROUND: Oxidative stress plays an important role in the pathology of ischemic stroke. Studies have confirmedthat scutellarin has antioxidant effects against ischemic injury, and we also reported that the involvement of Aldose reductase (AR) in oxidative stress and cerebral ischemic injury, in this study we furtherly explicit whether the antioxidant effect of scutellarin on cerebral ischemia injury is related to AR gene regulation and its specific mechanism. METHODS: C57BL/6N mice (Wild-type, WT) and AR knockout (AR-/-) mice suffered from transient middle cerebral artery occlusion (tMCAO) injury (1 h occlusion followed by 3 days reperfusion), and scutellarin was administered from 2 h before surgery to 3 days after surgery. Subsequently, neurological function was assessed by the modified Longa score method, the histopathological morphology observed with 2,3,5-triphenyltetrazolium chloride (TTC) and hematoxylin-eosin (HE) staining. Enzyme-linked immunosorbent assay (Elisa) was used to detect the levels of ROS, 4-hydroxynonenal (4-HNE), 8-hydroxydeoxyguanosine (8-OHDG), Neurotrophin-3 (NT-3), poly ADP-ribose polymerase-1 (PARP1) and 3-nitrotyrosine (3-NT) in the ischemic penumbra regions. Quantitative proteomics profiling using quantitative nano-HPLC-MS/MS were performed to compare the protein expression difference between AR-/- and WT mice with or without tMCAO injury. The expression of AR, nicotinamide adenine dinucleotide phosphate oxidases (NOX1, NOX2 and NOX4) in the ipsilateral side of ischemic brain were detected by qRT-PCR, Western blot and immunofluorescence co-staining with NeuN. RESULTS: Scutellarin treatment alleviated brain damage in tMCAO stroke model such as improved neurological function deficit, brain infarct area and neuronal injury and reduced the expression of oxidation-related products, moreover, also down-regulated tMCAO induced AR mRNA and protein expression. In addition, the therapeutic effect of scutellarin on the reduction of cerebral infarction area and neurological function deficits abolished in AR-/- mice under ischemia cerebral injury, which indicated that the effect of scutellarin treatment on tMCAO injury is through regulating AR gene. Proteomic analysis of AR-/- and WT mice indicated AR knockout would affect oxidation reaction even as NADPH related process and activity in mice under cerebral ischemia conditions. Moreover, NOX isoforms (NOX1, NOX2 and NOX4) mRNA and protein expression were significant decreased in neurons of penumbra region in AR-/- mice compared with that in WT mice at 3d after tMCAO injury, which indicated that AR should be the upstream protein regulating NOX after cerebral ischemia. CONCLUSIONS: We first reported that AR directly regulates NOX subtypes (not only NOX2 but also NOX1 and NOX4) after cerebral ischaemic injury. Scutellarin specifically targets the AR-NOX axis and has antioxidant effects in mice with cerebral ischaemic injury, providing a theoretical basis and accurate molecular targets for the clinical application of scutellarin.

The Novel lncRNA ENST00000530525 Affects ANO1, Contributing to Blood-Brain Barrier Injury in Cultured hCMEC/D3 Cells Under OGD/R Conditions.

Ischemic stroke (IS) is a major neurological disease with high fatality and residual disability burdens. Long noncoding RNAs (lncRNAs) have been found to play an important role in IS. However, the roles and significance of most lncRNAs in IS are still unknown. This study was performed to identify differentially expressed (DE) lncRNAs using a lncRNA microarray in whole blood samples of patients suffering from acute cerebral ischemia. Bioinformatics analyses, including GO, KEGG pathway enrichment analysis, and proximity to putative stroke risk location analysis were performed. The novel lncRNA, ENST00000530525, significantly decreased after IS. Furthermore, we evaluated lncRNA ENST00000530525 expression in cultured hCMEC/D3 cells under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions using fluorescent in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (RT-qPCR) analysis. To investigate the function of lncRNA ENST00000530525, its over-expression (OE) and negative control (NC) plasmids were transfected into hCMEC/D3 cells, and cell viability was detected by a cell counting kit-8 (CCK-8) assay after OGD/R. LncRNA ENST00000530525 and ANO1 expression were investigated using RT-qPCR and immunofluorescence. For blood-brain barrier (BBB) permeability, FITC-dextran transendothelial permeability assay and tight junction (TJ) protein immunofluorescence assays were performed. There were 3352 DE lncRNAs in the blood samples of acute IS patients. The validation results were consistent with the gene chip data. The GO and KEGG results showed that these lncRNAs were mainly related to oxygen and glucose metabolism, leukocyte transendothelial migration, mitophagy and cellular senescence. Among these, lncRNA ENST00000530525 was the most highly downregulated lncRNA and it was mapped within the IS-associated gene anoctamin-1 (ANO1). We further found that lncRNA ENST00000530525 was downregulated in hCMEC/D3 cells under 4 h OGD and 20 h reoxygenation (OGD4/R20) conditions. Upregulating lncRNA ENST00000530525 by plasmid transfection decreased cell viability while increasing ANO1 expression and it contributed to BBB injury in hCMEC/D3 cells after OGD4/R20. The lncRNA ENST00000530525 might play deleterious roles in post-stroke pathogenesis. These results show that some DE lncRNAs in humans participate through characteristic roles in post-stroke pathogenesis; thus, the roles and significance of some novel lncRNAs in IS warrant further study.

[Galangin alleviates learning and memory impairments in APP/PS1 double- transgenic mice by regulating Akt/MEF2D/Beclin-1 signaling pathway].

The study aimed to investigate the effects of galangin on learning and memory impairments and Akt/MEF2 D/Beclin-1 signaling pathway in APP/PS1 double-transgenic mice. The mice in this experiment were divided into the normal group, model group, low-(25 mg·kg~(-1)), medium-(50 mg·kg~(-1)), and high-dose(100 mg·kg~(-1)) galangin groups, donepezil(3 mg·kg~(-1)) group, Akt inhibitor(25 mg·kg~(-1)) group, and autophagy inhibitor(30 mg·kg~(-1)) group, with ten in each group, and administered with the corresponding drugs for 30 successive days. On the 24 th day of medication, the water maze and dark avoidance tests were performed. The levels of p-tau, ß-amyloid peptide 1-42(Aß_(42)), acetylcholinesterase(AChE), ß-site amyloid precursor protein cleaving enzyme 1(BACE1), and amyloid precursor protein(APP) in hippocampus were detected by ELISA, the Beclin-1 mRNA expression by RT-PCR, the expression of Aß_(42) and glial fibrillary acidic protein(GFAP) by immunohistochemistry, and the expression of myocyte enhancer factor 2 D(MEF2 D) by immunofluorescence assay. The pathological changes in hippocampus were observed after HE staining, and the expression of Akt, MEF2 D, and Beclin-1 in hippocampus were assayed by Western blot. These results showed that compared with the normal group, the model group exhibited prolonged swimming time, increased number of errors and electric shocks, up-regulated p-tau, Aß_(42), APP, AChE, BACE1, GFAP, and Beclin-1, shortened incubation period, decreased p-Akt and MEF2 D, and obvious hippocampal injury. Compared with the model group, donepezil and galangin shortened the swimming time, reduced the number of errors and electric shocks, down-regulated the expression of p-tau, Aß_(42), APP, AChE, BACE1, GFAP, and Beclin-1, prolonged the incubation period, up-regulated p-Akt and MEF2 D, and improved the pathological changes in hippocampus. Compared with the autophagy inhibitor group, galangin prolonged the swimming time, elevated the number of errors and electric shocks, enhanced the expression of p-tau, Aß_(42), APP, AChE, BACE1, GFAP, and Beclin-1, shortened the incubation period, and diminished the expression of p-Akt and MEF2 D. In conclusion, galangin improves the learning and memory impairments and hippocampal neuron injury of APP/PS1 mice, which may be related to its regulation of Akt/MEF2 D/Beclin-1 signaling pathway.

Naringenin Inhibits Platelet Activation and Arterial Thrombosis Through Inhibition of Phosphoinositide 3-Kinase and Cyclic Nucleotide Signaling.

Citrus flavanoids intake can reduce the risk of cardiovascular diseases. Naringenin, a natural predominant flavonoid abundant in citrus fruits, possesses protective effects against atherothrombotic diseases. As platelet activation plays central roles in atherothrombogenesis, we studied the effects of naringenin on platelet activation, signaling, thrombosis and hemostasis. Naringenin dose-dependently inhibited agonist-induced platelet aggregation in vitro, and exhibited more-potent efficacy on ADP-induced platelet aggregation. It also suppressed platelet aggregation stimulated by ADP ex vivo. Naringenin inhibited ADP-induced platelet α-granule secretion, fibrinogen binding, intracellular calcium mobilization and platelet adhesion on collagen-coated surface. Naringenin also inhibited platelet spreading on fibrinogen and clot retraction, processes mediated by outside-in integrin signaling. Mechanism studies indicated that naringenin suppressed PI3K-mediated signaling and phosphodiesterase activity in platelets, in addition to increasing cGMP levels and VASP phosphorylation at Ser239. Furthermore, naringenin-induced VASP phosphorylation and inhibition of platelet aggregation were reversed by a PKA inhibitor treatment. Interestingly, naringenin inhibited thrombus formation in the (FeCl3)-induced rat carotid arterial thrombus model, but not cause a prolonged bleeding time in mice. This study suggests that naringenin may represent a potential antiplatelet agent targeting PI3K and cyclic nucleotide signaling, with a low bleeding risk.

Dynamic changes in Beclin-1, LC3B and p62 at various time points in mice with temporary middle cerebral artery occlusion and reperfusion (tMCAO).

Ischaemic stroke is attributable to cerebrovascular disease and is associated with high morbidity, disability, mortality and recurrence. Autophagy is a critical mediator and plays dual roles in ischaemic stroke. Autophagy can protect against ischaemic brain injury during the early stage of ischaemic stroke, while excessive autophagy can induce apoptosis and exacerbate brain injury. However, the time-dependent variations in autophagy in ischaemic stroke are unknown. C57BL/6 mice were used to establish a model of temporary middle cerebral artery occlusion and reperfusion (tMCAO). The neurological functional scores and infarct volumes were determined at 1 d, 3 d, 5 d, and 7 d after modelling. The levels of Beclin-1, LC3B, p62, GFAP, TNF-α, IL-6, IL-10, ROS, 4-HNE and 8-OHDG were measured by ELISA, RT-PCR, immunofluorescence analysis and western blotting. The morphology of autophagosomes of ischaemic penumbra was observed by transmission electron microscopy (TEM). Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels increased (P < 0.01), while p62 and IL-10 levels decreased (P < 0.01) after tMCAO compared to those in the sham group. Beclin-1, LC3B, ROS, 4-HNE, 8-OHDG, GFAP, TNF-α and IL-6 levels were reduced in tMCAO mice at 3 d, 5 d and 7 d (P<0.05), and p62 and IL-10 levels were enhanced (P < 0.05) compared to those at 1 d. In addition, Beclin-1 positively correlated with LC3B, GFAP, TNF-α, IL-6, ROS, 4-HNE and 8-OHDG (P < 0.05), and Beclin-1 negatively correlated with p62 and IL-10 (P < 0.05). The number of autophagosomes was consistent with the expression of autophagy marker proteins, both showing a steady decrease. In summary, autophagy was activated within 7 d of tMCAO induction, and it strengthened at 1 d and then weakened steadily from 3 to 7 d. In addition, this study verified that autophagy positively correlated with the inflammatory response and oxidative stress at 7 d after tMCAO.

Dynamic Changes of Beclin-1 in the Hippocampus of Male Mice with Vascular Dementia at Different Time Points.

This study tried to investigate the dynamic changes of Beclin-1 in the hippocampus of male mice with vascular dementia (VD) at different time points. The mouse model of VD was established by the four-vessel blocking method. Then, the VD mice were randomly divided into five groups (n = 12) according to the disease duration: the 0.1-day model group, 0.5-day model group, 1-day model group, 3-day model group, 5-day model group and 14-day model group. In addition, all surgical procedures were the same in the sham group as those in the model groups, except the mice in the sham group were not subjected to clipping. The expression of Beclin-1, LC3B, p62, Bcl-2, Bax, BACE1, GFAP, MBP and ET-1 mRNA were determined by RT-PCR; the expression of Beclin-1 was detected by Western blot and immunofluorescence; the pathological characteristics of the hippocampus were observed by haematoxylin-eosin (HE) staining; and the correlation of Beclin-1 with other VD-related proteins was analysed by Pearson's correlation. Compared with that in the sham group, the expression of Beclin-1, LC3B, Bax, BACE1, GFAP, MBP and ET-1 mRNA was increased in the VD mice at different time points (0.1 day, 0.5 day, 1 day, 3 days, 5 days and 14 days) (P < 0.05) and then remained relatively stable in the 0.5-day VD mice, whereas the p62 and Bcl-2 mRNA levels decreased (P < 0.05). Beclin-1 protein expression was significantly increased in the VD mice at different time points (P < 0.05). The hippocampus showed a certain degree of neuronal damage in the VD mice at different time points (P < 0.05). Additionally, certain correlations among LC3B, p62, Bcl-2, Bax, BACE1, GFAP, MBP, ET-1 and Beclin-1 were observed in this study. In conclusion, the results described above demonstrated that neuronal damage and dynamic stability of Beclin-1 expression were established in the VD male mice after 0.5 day by the four-vessel blocking method.

Neferine alleviates memory and cognitive dysfunction in diabetic mice through modulation of the NLRP3 inflammasome pathway and alleviation of endoplasmic-reticulum stress.

Accumulating clinical and epidemiological evidence indicates a close relationship between diabetes mellitus and dysfunction in memory and cognition. Neferine (NE) is a unique bis-benzylisoquinoline alkaloid derived from the seed embryo of Nelumbo nucifera (Lotus), an herbal medicine with a long history of use in used in China. NE has been reported to ameliorate diabetes mellitus and exert considerable protective effects on the central nervous system. Thus, this study aimed to investigate the effects of NE on memory and cognitive dysfunction in db/db mouse model of diabetes. First, we found that NE treatments significantly ameliorated behavioral impairment and cognitive dysfunction in the Morris water maze, Y-maze, and fear conditioning test in db/db mice. Additionally, in these diabetic mice, NE decreased fasting glucose and insulin resistance while promoting lipid metabolism. Furthermore, NE treatments alleviated oxidative stress and inhibited inflammatory responses in the hippocampus. Further investigations showed that NE suppressed the NOD-like receptor protein 3 (NLRP3) inflammasome pathway via down-regulating the levels of thioredoxin-interacting protein (TXNIP), NLRP3 inflammasomes, apoptosis-associated speck-like protein containing a CARD (ASC), and mature interleukin-1ß (IL-1ß) in the hippocampus. Moreover, NE alleviated endoplasmic-reticulum (ER) stress via down-regulating the levels of immunoglobulin heavy-chain-binding protein (GRP78), C/EBP homologous protein (CHOP), proteins kinase R-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1), and activating transcription factor 6 (ATF6) in the hippocampus. In conclusion, these results suggest that NE ameliorated memory and cognitive dysfunction, possibly through modulating the NLRP3 inflammasome pathways and alleviating ER stress.

Effects of compound K, a metabolite of ginsenosides, on memory and cognitive dysfunction in db/db mice involve the inhibition of ER stress and the NLRP3 inflammasome pathway.

Accumulating clinical and epidemiological evidence indicates a close relationship between diabetes mellitus and dementia. The ginsenoside compound K (CK) has been reported to ameliorate diabetes mellitus and confer protection to the central nervous system. In this study, we investigated whether CK could improve memory impairment and cognitive dysfunction in diabetic db/db mice. Firstly, we found that CK treatments significantly improved behavioral impairment and cognitive dysfunction based on Morris water maze, Y-maze, and fear conditioning tests. Besides, CK decreased the fasting glucose level, increased lipid metabolism, and ameliorated glucose tolerance, insulin sensitivity, and dyslipidemia in diabetic db/db mice. In addition, CK treatments alleviated oxidative stress and inhibited the inflammatory response in hippocampal tissue. Further investigations showed that CK treatments inhibited the NLRP3 inflammasome pathway, as evidenced by the declined expression of TXNIP, NLRP3 inflammasomes, ASC, cleaved caspase-1, and mature IL-1ß in hippocampal tissues. Moreover, CK treatments alleviated ER stress via down-regulating the level of BiP, CHOP, p-PERK, p-IRE1α and ATF6 in the hippocampus of db/db mice. These results suggest that CK improves memory and cognitive dysfunction, possibly by ameliorating glucose tolerance, insulin sensitivity, and dyslipidemia, suppressing oxidative stress and inflammatory response and modulating the NLRP3 inflammasome pathway and ER stress.

ß­asarone modulates Beclin­1, LC3 and p62 expression to attenuate Aß40 and Aß42 levels in APP/PS1 transgenic mice with Alzheimer's disease.

Alzheimer's disease (AD) is a common neurodegenerative disease in the elderly population. Autophagy is a well­known regulator of neurodegenerative diseases and ß­asarone has been discovered to have certain neuropharmacological effects. Thus, the present study aimed to analyze the potential effects of ß­asarone in AD and its possible mechanism of action in relation to autophagy. The present study investigated the effects of ß­asarone on the number of senile plaques and amyloid ß(Aß)40, Aß42, amyloid precursor protein (APP) and Beclin­1 mRNA levels in the hippocampus of APP/presenilin­1 (PS1) transgenic mice. The possible mechanism of ß­asarone on autophagy­related proteins, including Beclin­1, light chain (LC)3A, LC3B and p62 levels, and the number of autophagosomes was also investigated. Mice were divided into a normal control group, a model group, a ß­asarone­treated group, a 3­MA­treated group and a rapamycin­treated group. Treatments were continuously administered to all mice for 30 days by intragastric administration. The mice, including those in the normal and model control groups, were given equal volumes of saline. It was demonstrated that ß­asarone treatment reduced the number of senile plaques and autophagosomes, and decreased Aß40, Aß42, APP and Beclin­1 expression in the hippocampus of model mice compared with untreated model mice. ß­asarone also inhibited LC3A/B expression levels, but increased p62 expression. It was deduced that the neuroprotective effects of ß­asarone in APP/PS1 transgenic mice resulted from its inhibition of autophagy. In conclusion, the data suggested that ß­asarone should be explored further as a potential therapeutic agent in AD.

Protocatechuic acid attenuates ß­secretase activity and okadaic acid­induced autophagy via the Akt/GSK­3ß/MEF2D pathway in PC12 cells.

Okadaic acid (OA) can be used to induce an Alzheimer's disease (AD) model characterized by tau hyperphosphorylation, the formation of neurofibrillary tangles formation and ß­amyloid (Aß) deposition. Previous studies have shown that the upregulation of Beclin­1­dependent autophagy may contribute to the elimination of aggregated Aß. However, the effects of protocatechuic acid (PA) on the levels of Aß42, phosphorylated (p)­tau and ß­secretase in OA­induced cell injury are unclear, and little is known concerning the role of the PA signaling pathway in the regulation of autophagy. The present study aimed to determine whether PA protects cells from OA­induced cytotoxicity via the regulation of Beclin­1­dependent autophagy and its regulatory signaling pathway. PC12 cells were treated with OA with or without PA for 24 h. Enzymatic assays were performed to measure p­tau, Aß42 and ß­secretase activity. Western blotting was performed to detect p­Akt, p­glycogen synthase kinase­3ß (p­GSK­3ß), Akt, GSK­3ß, myocyte enhancer factor 2D (MEF2D) and Beclin­1 protein expression levels. Immunofluorescence and immunocytochemistry were used to measure Beclin­1 expression levels. The results from this study showed that PA could increase cell viability and significantly decrease the levels of Aß42, p­tau, ß­secretase and Beclin­1. PA can also promote the expression of p­Akt and MEF2D while suppressing the expression of p­GSK­3ß. These results indicated that PA protects PC12 cells from OA­induced cytotoxicity, and attenuates autophagy via regulation of the Akt/GSK­3ß/MEF2D pathway, therefore potentially contributing to the neuroprotective effects of PA against OA toxicity. These findings suggested that PA may have potential as a drug candidate in preventative AD therapy.

Scutellarin-treated exosomes increase claudin 5, occludin and ZO1 expression in rat brain microvascular endothelial cells.

Homocysteine has been reported to be an independent risk factor for stroke. Scutellarin (Scu) dilates cerebral blood vessels and promotes anti-platelet aggregation; however, the mechanism by which Scu and Scu-treated exosomes protect against cerebrovascular disease is unclear. The aim of the present study was to investigate the mechanisms underlying the effects of Scu and Scu-treated exosomes on tight junction proteins in the blood-brain barrier. Rat brain microvascular endothelial cells (RBMVECs) were cultured and divided into five groups: Control, model, Scu, exosomes derived from RBMVECs and exosomes derived from RBMVECs after Scu administration. MTT, lactate dehydrogenase (LDH) and nitric oxide (NO) assays were performed to assess cell viability and injury. Reactive oxygen species (ROS) levels were detected using spectrophotometry and immunofluorescence. Western blotting and immunofluorescence were performed to measure cluster of differentiation (CD) 63, claudin 5, occludin and tight junction protein 1 (ZO1) expression. The results revealed that treatment with Scu and Scu-treated exosomes enhanced cell viability, reduced cell injury, increased NO levels, upregulated CD63, claudin 5, occludin and ZO1, and decreased LDH and ROS levels. These data suggest that Scu and Scu-treated exosomes protect homocysteine-induced RBMVECs via increased claudin 5, occludin and ZO1 expression.

ß-Asarone Regulates ER Stress and Autophagy Via Inhibition of the PERK/CHOP/Bcl-2/Beclin-1 Pathway in 6-OHDA-Induced Parkinsonian Rats.

ß-Asarone (1,2,4-trimethoxy-5-[(Z)-prop-1-enyl]benzene) is an essential component of Acorus tatarinowii Schott volatile oil. Previous research has observed that ß-asarone effectively attenuated symptoms in parkinsonian rats and improved their performance, but the mechanism of this effect remains unclear. Other research has shown that endoplasmic reticulum (ER) stress plays an important role in the pathogenesis of Parkinson's disease (PD). The protein kinase RNA-like endoplasmic reticulum kinase (PERK) was observed in the nigrostriatal dopaminergic neurons of patients with PD. However, our group observed that ER stress and autophagy occurred in 6-hydroxy dopamine (6-OHDA)-induced parkinsonian rats, and ER stress might induce autophagy. We assume that the protective role of ß-asarone in parkinsonian rats is mediated via the ER stress-autophagy pathway. To support this hypothesis, we investigated the expressions of glucose regulated protein 78 (GRP78), PERK phosphorylation (p-PERK), C/EBP homologous binding protein (CHOP), Bcl-2 and Beclin-1 in 6-OHDA-induced parkinsonian rats after ß-asarone treatment. The results showed that the ß-asarone group and PERK inhibitor group had lower levels of GRP78, p-PERK, CHOP and Beclin-1 while having higher levels of Bcl-2. We deduced that ß-asarone might regulate the ER stress-autophagy via inhibition of the PERK/CHOP/Bcl-2/Beclin-1 pathway in 6-OHDA-induced parkinsonian rats.

Endoplasmic reticulum stress induced autophagy in 6-OHDA-induced Parkinsonian rats.

Both endoplasmic reticulum (ER) stress and autophagy involve in the pathological process of Parkinson's disease (PD). But the relationship between them is not clear in PD. A 6-OHDA-induced parkinsonian rat is recognized as a standard model for many years, and it can be used in experimental study. The glucose regulated protein 78 (GRP78) is a master regulator of ER stress, and the C/EBP homologous binding protein (CHOP) is an indicator of the UPR signaling. Besides, the Beclin-1 is also well known as a regulator of autophagy, and P62 is a specific marker to monitor autophagy. Therefore, we investigated the expressions of GRP78, CHOP, Beclin-1 and P62 in 6-OHDA-induced parkinsonian rat. Unilateral 6-OHDA injection into medial forebrain bundle was used except sham-operated rats. The rats were randomly divided into 6 groups: a sham-operated group; a model group; a 3-methyladenine (3-MA) group, administered 3-MA---autophagy inhibitor; a rapamycin group, administered rapamycin---autophagy inducer; a 4-phenylbutyric acids (4-PBA) group, administered 4-PBA---ER stress inhibitor; a tunicamycin (TM) group, administered TM---ER stress inducer. The results showed that the expressions of GRP78, CHOP and Beclin-1 increased, P62 decreased in model group; the expressions of GRP78 and CHOP were unchanged in 3-MA group and rapamycin group; but the expression of Beclin-1 decreased and P62 increased in 4-PBA group, while the expression of Beclin-1 increased and P62 decreased in TM group. These data suggest that ER stress and autophagy occurred in 6-OHDA-induced parkinsonian rat, and ER stress might induce autophagy. The result is important for the pathological mechanism of PD.

Galangin decreases p­tau, Aß42 and ß­secretase levels, and suppresses autophagy in okadaic acid­induced PC12 cells via an Akt/GSK3ß/mTOR signaling­dependent mechanism.

Okadaic acid (OA)­induced neurotoxicity may be considered a novel tool used to study Alzheimer's disease (AD) pathology, and may be helpful in the development of a novel therapeutic approach. It has been reported that galangin inhibits ß­site amyloid precursor protein­cleaving enzyme 1 expression, which is a key enzyme for amyloid ß (Aß) generation and is a potential drug candidate for AD therapy. However, further studies are required to confirm its neuroprotective effects in other AD models. The present study aimed to explore the neuroprotective effects of galangin on OA­induced neurotoxicity in PC12 cells. The cells were divided into the following groups: Control group, model group (175 nM OA for 48 h) and galangin groups (0.25, 0.5 and 1 µg/ml). Beclin­1, phosphorylated (p)­protein kinase B (Akt), p­glycogen synthase kinase (GSK)3ß and p­mechanistic target of rapamycin (mTOR) expression was also measured in the following PC12 cell groups: Control group, model group, 3­methyladenine group (5 nM), rapamycin group (100 nM) and galangin group (1 µg/ml). The levels of ß­secretase, Aß42 and p­tau were detected by ELISA, Beclin­1 expression was examined by immunohistochemistry and the protein expression levels of p­Akt, p­mTOR p­GSK3ß, and Beclin­1 were detected by western blotting. Galangin treatment enhanced cell viability in cells treated with OA, and decreased ß­secretase, Aß42 and p­tau levels. In addition, it suppressed Beclin­1 and p­GSK3ß expression, but promoted p­Akt and p­mTOR expression by regulating the Akt/GSK3ß/mTOR pathway. These results indicated that galangin protected PC12 cells from OA­induced cytotoxicity and inhibited autophagy via the Akt/GSK3ß/mTOR pathway, thus suggesting that it may be considered a potential therapeutic agent for AD.

Scutellarin protects oxygen/glucose-deprived astrocytes and reduces focal cerebral ischemic injury.

Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxidative effects and has been used to treat cardiovascular and cerebrovascular diseases in China. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 µM scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco's modified Eagle's medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 µM scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen species in astrocytes subjected to ischemia-reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine (8-OHdG), 4-hydroxy-2-nonenal (4-HNE) and 3-nitrotyrosin (3-NT) in brain tissue. Immunofluorescence double staining was used to determine the co-expression of caspase-3 and NeuN. Pretreatment with scutellarin improved the neurological function of rats with focal cerebral ischemia, reduced infarct size, diminished the expression of NOX2, reduced levels of 8-OHdG, 4-HNE and 3-NT, and reduced the number of cells co-expressing caspase-3 and NeuN in the injured brain tissue. Furthermore, we examined the effect of the NOX2 inhibitor apocynin. Apocynin substantially increased connexin 43 expression in vivo and in vitro. Collectively, our findings suggest that scutellarin protects against ischemic injury in vitro and in vivo by downregulating NOX2, upregulating connexin 43, decreasing oxidative damage, and reducing apoptotic cell death.