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Neuroinflammation is a critical aspect of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. This study investigates the anti-neuroinflammatory properties of oleocanthal and its oxidation product, oleocanthalic acid, using the BV-2 cell line activated with lipopolysaccharide. Our findings revealed that oleocanthal significantly inhibited the production of pro-inflammatory cytokines and reduced the expression of inflammatory genes, counteracted oxidative stress induced by lipopolysaccharide, and increased cell phagocytic activity. Conversely, oleocanthalic acid was not able to counteract lipopolysaccharide-induced activation. The docking analysis revealed a plausible interaction of oleocanthal, with both CD14 and MD-2 leading to a potential interference with TLR4 signaling. Since our data show that oleocanthal only partially reduces the lipopolysaccharide-induced activation of NF-kB, its action as a TLR4 antagonist alone cannot explain its remarkable effect against neuroinflammation. Proteomic analysis revealed that oleocanthal counteracts the LPS modulation of 31 proteins, including significant targets such as gelsolin, clathrin, ACOD1, and four different isoforms of 14-3-3 protein, indicating new potential molecular targets of the compound. In conclusion, oleocanthal, but not oleocanthalic acid, mitigates neuroinflammation through multiple mechanisms, highlighting a pleiotropic action that is particularly important in the context of neurodegeneration. [ABSTRACT FROM AUTHOR]

Neuroinflammation is a critical aspect of various neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. This study investigates the anti-neuroinflammatory properties of oleocanthal and its oxidation product, oleocanthalic acid, using the BV-2 cell line activated with lipopolysaccharide. Our findings revealed that oleocanthal significantly inhibited the production of pro-inflammatory cytokines and reduced the expression of inflammatory genes, counteracted oxidative stress induced by lipopolysaccharide, and increased cell phagocytic activity. Conversely, oleocanthalic acid was not able to counteract lipopolysaccharide-induced activation. The docking analysis revealed a plausible interaction of oleocanthal, with both CD14 and MD-2 leading to a potential interference with TLR4 signaling. Since our data show that oleocanthal only partially reduces the lipopolysaccharide-induced activation of NF-kB, its action as a TLR4 antagonist alone cannot explain its remarkable effect against neuroinflammation. Proteomic analysis revealed that oleocanthal counteracts the LPS modulation of 31 proteins, including significant targets such as gelsolin, clathrin, ACOD1, and four different isoforms of 14-3-3 protein, indicating new potential molecular targets of the compound. In conclusion, oleocanthal, but not oleocanthalic acid, mitigates neuroinflammation through multiple mechanisms, highlighting a pleiotropic action that is particularly important in the context of neurodegeneration.

Background: Oxidative stress is one of the pivotal pathogenesis of ischemic stroke. Orientin, a compound extracted from plants, has been previously reported to have antioxidant activity that was exploited in various diseases. The objective of this study was to focus on the potential therapeutic effects of orientin on cobalt chloride (CoCl2)-induced Hypoxia Reoxygenation (HR) injury in BV-2 microglial cells and to explore the possible mechanisms. Materials and Methods: The optimum protective condition of orientin on BV-2 microglial cells after HR injury was evaluated by the viability of cells measured by Cell Counting Kit-8 (CCK-8). Afterwards, functions of Superoxide Dismutase (SOD) and Catalase (CAT) as well as the content of Glutathione Peroxidase (GSH-PX) were measured by corresponding kits. Activation of Nrf2 pathway was assayed by western blotting. Results: Our study demonstrates that the viability of HR injured BV-2 microglial cells was improved significantly after incubation with orientin (40~100 µg/mL) for 8 hr. Furthermore, orientin was found to increase the nuclear translocation of Nrf2 protein in BV-2 microglial cells and was shown to promote antioxidant enzyme activities and enhance the expression of HO-1 and NQO1. Conclusion: Taken together, Results of our study indicate that orientin protect BV-2 microglial cells against HR injury induced by CoCl2, and this protection is associated with the inhibition of oxidative stress through the activation of the Nrf2 signaling pathway. [ABSTRACT FROM AUTHOR]

Chronic neuroinflammation is associated with many neurodegenerative diseases, such as Alzheimer's. Microglia are the brain's primary immune cells, and when activated, they release various proinflammatory cytokines. Several natural compounds with anti-inflammatory and antioxidant properties, such as epigallocatechin 3-gallate (EGCG), may provide a promising strategy for inflammation-related neurodegenerative diseases involving activated microglia cells. The objective of the current study was to examine the molecular targets underlying the anti-inflammatory effects of EGCG in activated microglia cells. BV-2 microglia cells were grown, stimulated, and treated with EGCG. Cytotoxicity and nitric oxide (NO) production were evaluated. Immunoassay, PCR array, and WES™ Technology were utilized to evaluate inflammatory, neuroprotective modulators as well as signaling pathways involved in the mechanistic action of neuroinflammation. Our findings showed that EGCG significantly inhibited proinflammatory mediator NO production in LPS-stimulated BV-2 microglia cells. In addition, ELISA analysis revealed that EGCG significantly decreases the release of proinflammatory cytokine IL-6 while it increases the release of TNF-α. PCR array analysis showed that EGCG downregulated MIF, CCL-2, and CSF2. It also upregulated IL-3, IL-11, and TNFS10. Furthermore, the analysis of inflammatory signaling pathways showed that EGCG significantly downregulated mRNA expression of mTOR, NF-κB2, STAT1, Akt3, CCL5, and SMAD3 while significantly upregulating the expression of mRNA of Ins2, Pld2, A20/TNFAIP3, and GAB1. Additionally, EGCG reduced the relative protein expression of NF-κB2, mTOR, and Akt3. These findings suggest that EGCG may be used for its anti-inflammatory effects to prevent neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eleven undescribed dihydrophenanthrene dimers were isolated from Pholidota yunnanensis. • The absolute configurations of 15 pairs of enantiomers were established by the rotational barriers and calculated ECD spectra. • Compound 7 showed promising anti-neuroinflammatory effect through suppress the expression of inflammatory factors. • In this study, the optical properties of dihydrophenanthrenes were analyzed and discussed. Axially chiral compounds are well known in medicinal chemistry of natural products, but their absolute configurations and bioactivities are rarely reported and studied. In this study, eleven undescribed axially chiral dihydrophenanthrene dimers, as well as twenty-five known dihydrophenanthrenes, were isolated from the entire plant of Pholidota yunnanensis. Their structures were elucidated by comprehensive spectroscopic analysis. A method for determining the absolute configurations of enantiomers was developed based on the rotational barriers and calculated ECD spectra. Additionally, the activities of all isolated compounds were assessed in LPS-induced BV-2 microglial cells. Most dihydrophenanthrenes exhibited significant NO inhibitory activities, and compound 7 showed the most potent inhibitory effect with an IC 50 value of 1.5 μM, compared to the positive control minocycline. The immunofluorescence and western blot results revealed that compound 7 suppressed the expression of Iba-1, iNOS and COX-2 in LPS-stimulated BV-2 microglial cells. [ABSTRACT FROM AUTHOR]

Chronic neuroinflammation is associated with many neurodegenerative diseases, such as Alzheimer’s. Microglia are the brain’s primary immune cells, and when activated, they release various proinflammatory cytokines. Several natural compounds with anti-inflammatory and antioxidant properties, such as epigallocatechin 3-gallate (EGCG), may provide a promising strategy for inflammation-related neurodegenerative diseases involving activated microglia cells. The objective of the current study was to examine the molecular targets underlying the anti-inflammatory effects of EGCG in activated microglia cells. BV-2 microglia cells were grown, stimulated, and treated with EGCG. Cytotoxicity and nitric oxide (NO) production were evaluated. Immunoassay, PCR array, and WES™ Technology were utilized to evaluate inflammatory, neuroprotective modulators as well as signaling pathways involved in the mechanistic action of neuroinflammation. Our findings showed that EGCG significantly inhibited proinflammatory mediator NO production in LPS-stimulated BV-2 microglia cells. In addition, ELISA analysis revealed that EGCG significantly decreases the release of proinflammatory cytokine IL-6 while it increases the release of TNF-α. PCR array analysis showed that EGCG downregulated MIF, CCL-2, and CSF2. It also upregulated IL-3, IL-11, and TNFS10. Furthermore, the analysis of inflammatory signaling pathways showed that EGCG significantly downregulated mRNA expression of mTOR, NF-κB2, STAT1, Akt3, CCL5, and SMAD3 while significantly upregulating the expression of mRNA of Ins2, Pld2, A20/TNFAIP3, and GAB1. Additionally, EGCG reduced the relative protein expression of NF-κB2, mTOR, and Akt3. These findings suggest that EGCG may be used for its anti-inflammatory effects to prevent neurodegenerative diseases.

Banisteriopsis caapi is used to prepare the psychoactive beverage ayahuasca, and both have therapeutic potential for the treatment of many central nervous system (CNS) conditions. This study aimed to isolate new bioactive compounds from B. caapi extract and evaluate their biological activity, and that of the known β-carboline components of the plant (harmine, harmaline, and tetrahydroharmine), in BV-2 microglial cells, the in vivo activation of which is implicated in the physiopathology of CNS disorders. B. caapi extract was fractionated using semipreparative liquid chromatography (HPLC-DAD) and the exact masses ([M + H]+m/z) of the compounds in the 5 isolated fractions were determined by high-resolution LC-MS/MS: F1 (174.0918 and 233.1289), F2 (353.1722), F3 (304.3001), F4 (188.1081), and F5 (205.0785). Harmine (75.5–302 µM) significantly decreased cell viability after 2 h of treatment and increased the number of necrotic cells and production of reactive oxygen species at equal or lower concentrations after 24 h. F4 did not impact viability but was also cytotoxic after 24 h. Most treatments reduced proinflammatory cytokine production (IL-2, IL-6, IL-17, and/or TNF), especially harmaline and F5 at 2.5 µM and higher concentrations, tetrahydroharmine (9.3 µM and higher), and F5 (10.7 µM and higher). The results suggest that the compounds found in B. caapi extract have anti-inflammatory potential that could be explored for the development of treatments for neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

[Display omitted] • The biological and phytochemical study on Croton lauioides was investigated firstly. • 23 conjugated enone-type components, including nine undescribed ones were obtained. • Guaianes with aromatic moiety exhibited potent NO-suppression effects in BV-2 cells. • Compound 5 showed promising anti-neuroinflammatory effect through the NF- κ B pathway. In this study, the chemical composition and pharmacological activity of Croton lauioides were investigated for the first time. The bioactive and HPLC-UV guided isolation led to the discovery of twenty-three conjugated enone-type components (1 – 23), including nine previously unknown sesquiterpenoid derivatives (1 – 4 , 9 – 10 , 12 – 14). Notably, compounds 1 and 12 are epoxides containing an endoperoxide bridge (1) or a unique dioxaspiro core (12), respectively. Compounds 2 – 7 are non-benzenoid aromatics featuring a tropone function, while 9 – 11 possess a rare rearranged scaffold with tropone shift into benzene. Extensive characterization was performed using NMR spectra, HRESIMS data, and electronic circular dichroism (ECD) calculations. Furthermore, we evaluated the bioactivities of all isolated compounds against neuroinflammation in LPS-stimulated BV-2 microglial cells. Remarkably, most sesquiterpenoid derivatives exhibited significant NO inhibit activities, and compound 5 showed the most potent effect with an IC 50 value of 0.14 ± 0.04 μM. Structure-activity relationship (SAR) analysis revealed that sesquiterpenoids modified with endocyclic enone conjugation may serve as a key pharmacophore for NO inhibition, particularly involving aromatic tropone moiety. The qPCR and Western blot results demonstrated that 5 exerted an inhibitory effect on the mRNA levels of iNOS, TNF- α and COX-2 in a time-dependent manner, as well as suppressed the protein expression of iNOS, TNF- α , COX-2. In mechanism, 5 could prevented activation of NF- κ B pathway by suppressing phosphorylation of p65 and I κ B- α. These findings revealed C. lauioides might be a promising resource for drug candidate development targeting neuroinflammation. [ABSTRACT FROM AUTHOR]

From the 95% ethanol aqueous extract of the roots of Clausena lansium , six previously undescribed alkaloids (1 , 2a , 2b , 15 , 24a , 24b), a pair of prenylated phenylpropenols (26a , 26b), two coumarins (27 , 28), and two undescribed sesquiterpenes (37 , 38) were isolated and identified using spectroscopic and electron circular dichroism data, together with thirty-two known compounds. The absolute configurations of three alkaloids (3a , 3b , 4a) were determined for the first time. In vitro assay showed that alkaloids 7 , 10 , 12 , 19 , and furanocoumarins 34 , 35 displayed inhibitory effects on the production of nitric oxide in lipopolysaccharide (LPS)-induced BV-2 microglial cells, which were stronger than that of the minocycline (positive control). RT-PCR results indicated that indizoline (7) could inhibit the expression of pro-inflammatory factors (IL-1 β , TNF- α, and IL-6) in LPS-treated BV-2 cells. Study on natural inhibitors against overactivation of microglial cells from the roots of Clausena lansium. [Display omitted] • Twelve undescribed compounds were reported for the first time. • All compounds were evaluated for NO production inhibitory effects in vitro. • Indizoline could inhibit the expression of pro-inflammatory factors in BV-2 cells. [ABSTRACT FROM AUTHOR]

Alzheimer’s disease (AD) is a degenerative disease of the central nervous system with unclear etiology and pathogenesis. In recent years, as the infectious theory and endotoxin hypothesis of AD has gained substantial attention, several studies have proposed that Porphyromonas gingivalis (P. gingivalis), one of the main pathogenic bacteria of chronic periodontitis, and the lipopolysaccharide (LPS) of P. gingivalis may lead to AD-like pathological changes and cognition impairment. However, research on the relationship between P. gingivalis-LPS and neuroinflammation is still lacking. Our study aimed to investigate the effects of P. gingivalis-LPS preparation on immuno-inflammation in microglial cells and further compared the differential inflammatory response induced by P. gingivalis-LPS and Escherichia coli (E. coli) LPS preparations. The results showed that P. gingivalis-LPS could upregulate the gene expression and release of pro-inflammatory factors in BV-2 microglial cells, including IL-1β, IL-6, TNF-α, IL-17, and IL-23. We also observed an increase in the level of Toll-like receptor 2/4 (TLR2/4) and NF-κB/STAT3 signaling. Moreover, the changes mentioned above were more significant in the E. coli-LPS group and the effects of both kinds of LPS could be differentially reversed by the administration of the TLR2 inhibitor C29 and TLR4 inhibitor TAK-242. The molecular simulation showed that the binding affinity of P. gingivalis-lipid A to TLR4-MD-2 was weaker than E. coli-lipid A, which was probably due to the presence of fewer acyl chains and phosphate groups of P. gingivalis-lipid A than E. coli-lipid A. We conclude that P. gingivalis-LPS could activate TLR2/4-mediated NF-κB/STAT3 signaling pathways, which ultimately resulted in an immune-inflammatory response in BV-2 microglia. In contrast to E. coli-LPS, P. gingivalis-LPS is a weaker TLR2/4 agonist and NF-κB/STAT3 signaling activator. Furthermore, the different fatty acid chains and phosphate groups between P. gingivalis-lipid A and E. coli-lipid A may be the reason for the weaker activating properties of P. gingivalis-LPS.

Alzheimer's disease (AD) is a degenerative disease of the central nervous system with unclear etiology and pathogenesis. In recent years, as the infectious theory and endotoxin hypothesis of AD has gained substantial attention, several studies have proposed that Porphyromonas gingivalis (P. gingivalis), one of the main pathogenic bacteria of chronic periodontitis, and the lipopolysaccharide (LPS) of P. gingivalis may lead to AD-like pathological changes and cognition impairment. However, research on the relationship between P. gingivalis -LPS and neuroinflammation is still lacking. Our study aimed to investigate the effects of P. gingivalis -LPS preparation on immuno-inflammation in microglial cells and further compared the differential inflammatory response induced by P. gingivalis -LPS and Escherichia coli (E. coli) LPS preparations. The results showed that P. gingivalis -LPS could upregulate the gene expression and release of pro-inflammatory factors in BV-2 microglial cells, including IL-1β, IL-6, TNF-α, IL-17, and IL-23. We also observed an increase in the level of Toll-like receptor 2/4 (TLR2/4) and NF-κB/STAT3 signaling. Moreover, the changes mentioned above were more significant in the E. coli -LPS group and the effects of both kinds of LPS could be differentially reversed by the administration of the TLR2 inhibitor C29 and TLR4 inhibitor TAK-242. The molecular simulation showed that the binding affinity of P. gingivalis -lipid A to TLR4-MD-2 was weaker than E. coli -lipid A, which was probably due to the presence of fewer acyl chains and phosphate groups of P. gingivalis -lipid A than E. coli -lipid A. We conclude that P. gingivalis -LPS could activate TLR2/4-mediated NF-κB/STAT3 signaling pathways, which ultimately resulted in an immune-inflammatory response in BV-2 microglia. In contrast to E. coli -LPS, P. gingivalis -LPS is a weaker TLR2/4 agonist and NF-κB/STAT3 signaling activator. Furthermore, the different fatty acid chains and phosphate groups between P. gingivalis -lipid A and E. coli -lipid A may be the reason for the weaker activating properties of P. gingivalis -LPS. [ABSTRACT FROM AUTHOR]

Banisteriopsis caapi is used to prepare the psychoactive beverage ayahuasca, and both have therapeutic potential for the treatment of many central nervous system (CNS) conditions. This study aimed to isolate new bioactive compounds from B. caapi extract and evaluate their biological activity, and that of the known β-carboline components of the plant (harmine, harmaline, and tetrahydroharmine), in BV-2 microglial cells, the in vivo activation of which is implicated in the physiopathology of CNS disorders. B. caapi extract was fractionated using semipreparative liquid chromatography (HPLC-DAD) and the exact masses ([M + H]+m/z) of the compounds in the 5 isolated fractions were determined by high-resolution LC-MS/MS: F1 (174.0918 and 233.1289), F2 (353.1722), F3 (304.3001), F4 (188.1081), and F5 (205.0785). Harmine (75.5–302 µM) significantly decreased cell viability after 2 h of treatment and increased the number of necrotic cells and production of reactive oxygen species at equal or lower concentrations after 24 h. F4 did not impact viability but was also cytotoxic after 24 h. Most treatments reduced proinflammatory cytokine production (IL-2, IL-6, IL-17, and/or TNF), especially harmaline and F5 at 2.5 µM and higher concentrations, tetrahydroharmine (9.3 µM and higher), and F5 (10.7 µM and higher). The results suggest that the compounds found in B. caapi extract have anti-inflammatory potential that could be explored for the development of treatments for neurodegenerative diseases.

Alzheimer's disease (AD) is a chronic neurodegenerative disease leading to progressive dementia in elderly people. The disease is characterized, among others, by formation of amyloid- β (A β) polypeptide plaques in the brain. Although etiology of the disease is not fully understood, recent research suggest that nanomaterials may affect AD development. Here, we described the consequences of exposure of mouse BV-2 microglia to silver nanoparticles (AgNPs, 50 µg/mL), cerium oxide nanoparticles (CeO2NPs, 100 µg/mL), and cadmium telluride quantum dots (CdTeQDs, 3 or 10 µg/mL) in the context of its ability to clear A β plaques. The brain microglial cells play an important role in removing A β plaques from the brain. Cell viability and cycle progression were assessed by trypan blue test and propidium iodide binding, respectively. The uptake of A β and NPs was measured by flow cytometry. Secretion of proinflammatory cytokines was measured with the use of cytometric bead array. A β (0.1 μM) did not affect viability, whereas NPs decreased microglia growth by arresting the cells in G1 phase (CdTeQDs) or in S phase (AgNPs and CeO2NPs) of cell cycle. The uptake of A β was significantly reduced in the presence of AgNPs and CeO2NPs. In addition, the least toxic CeO2NPs induced the release of proinflammatory cytokine, tumor necrosis factor α. In summary, each of the NPs tested affected either the microglia phagocytic activity (AgNPs and CeO2NPs) and/or its viability (AgNPs and CdTeQDs) that may favor the occurrence of AD and accelerate its development. [ABSTRACT FROM AUTHOR]

Neuroinflammation resulting from microglial activation is involved in the pathogenesis of neurodegenerative diseases, including Parkinson's diseases. Microglial activation plays an important role in neuroinflammation and contributes to several neurological disorders. Hence, inhibition of both microglial activation and the generation of pro-inflammatory cytokines may lead to an effective treatment for neurodegenerative diseases. In the present study, the anti-neuroinflammatory effects of galangin were investigated in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Galangin significantly decreased the generation of nitric oxide, interleukin-1β, and inducible nitric oxide synthase in LPS-stimulated BV-2 microglial cells. In addition, galangin inhibited the phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase 1/2. Furthermore, it was observed that activation of both IκB-α and nuclear factor kappa B (NF-κB) was significantly increased following LPS stimulation, and this effect was suppressed by galangin treatment. In conclusion, galangin displayed an anti-neuroinflammatory activity in LPS-stimulated BV-2 microglial cells. Galangin inhibited LPS-induced neuroinflammation via the MAPK and NF-κB signaling pathways and might act as a natural therapeutic agent for the treatment of various neuroinflammatory conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • 10 undescribed clerodane diterpenoids were isolated from Tinospora crispa. • Compounds 3, 4 and 6 contain ternary epoxy motify in the structure. • Compounds 3 and 8 exhibited potent NO inhibitory activity. • Compound 3 exert anti-inflammatory activity via inhibit TLR4 dependent Stat3 and MAPK, and active the HO-1. A total of 17 structurally diverse clerodane diterpenoids , including ten undescribed clerodane diterpenoids (tinopanoids K-T, 1 – 10) and seven known compounds (11 – 17), were isolated from the vines and leaves of Tinospora crispa. Compound 3 has not only bear the dominant substituents of γ -hydroxy- α , β -unsaturated- γ -lactone with anti-inflammatory activity, but also a ternary epoxy structure at C-3/C-4. The planar structures and relative configurations of the clerodane diterpenoids were elucidated by spectroscopic data interpretation. The absolute configurations of compounds 1 , 4 , 8 and 13 were determined by single-crystal X-ray crystallographic, while that of compound 3 was determined using computed ECD data and single crystal X-ray diffraction of related p -bromobenzoate ester (3a). Subsequently, all compounds were evaluated for their inhibitory effect on nitric oxide (NO) production of LPS-activated BV-2 cells, and compounds 3 and 8 exhibited better NO inhibitory potency, with IC 50 values of 5.6 and 13.8 μ M than the positive control minocycline (Mino, IC 50 = 22.9 μ M). The corresponding results of western blot analysis and qRT-PCR revealed that compound 3 can significantly inhibit the inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) protein expressions, mRNA levels of pro-inflammatory cytokins of tumor necrosis factor- α (TNF- α), interleukin 6 (IL-6) and interleukin 1 β (IL-1 β). The underlying mechanism by which compound 3 exerted anti-neuroinflammatory effects was investigated by western blot and immunofluorescence assay, which suggested compound 3 inhibited LPS induced neuroinflammation via the suppression of toll-like receptor 4 (TLR4) dependent Signal Transducer and Activator of Transcription 3 (Stat3) and mitogen-activated protein kinase (MAPK) signaling pathways, and the activation of Heme Oxygenase-1 (HO-1) mediated signals. [ABSTRACT FROM AUTHOR]

The ethyl acetate fraction from the seeds of Swietenia macrophylla (SMEAF) was studied for anti-inflammatory properties using lipopolysaccharide (LPS)-induced BV-2 microglia. SMEAF significantly attenuated the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6). SMEAF inhibited nuclear translocation of nuclear factor-kappa B (NF-κB) via the attenuation of IκBα phosphorylation. Moreover, SMEAF markedly suppressed phosphorylation of Akt, p38 Mitogen-activated protein kinase (MAPK) and Extracellular signal-regulated kinase 1/2 (ERK1/2) in LPS-induced BV-2 cells. Treatment with specific inhibitors for Akt, NF-κB, p38 and ERK1/2 resulted in the attenuation of iNOS and COX-2 protein expression. These findings indicated that SMEAF possesses anti-inflammatory activities in BV-2 cells by modulating LPS-induced pro-inflammatory mediator production via the inhibition of Akt-dependent NF-κB, p38 MAPK and ERK1/2 activation. These results further advocate the potential use of S. macrophylla as nutraceutical for the intervention of neurodegenerative and neuroinflammatory disorders.

Abstract Two new cadinane sesquiterpene glucosides (1 , 2), two new phenylpropanoid glycosides (3 , 4), and two new diterpenoid glucosides (5 , 6), as well as 6 known compounds were isolated from the stems of Tinospora sinensis. The structures of these compounds were elucidated by extensive spectroscopic analysis and chemical methods. The absolute configuration of compound 1 was determined by timedependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations and in situ dimolybdenum CD method. All the isolated compounds except for compounds 7 , 11 and 12 were evaluated for their anti-neuroinflammatory effect by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells, and compound 4 showed anti-neuroinflammatory activity with IC 50 values 42.90 μM in vitro assay. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Highlights • S100A8/A9 induces the activation, proliferation and migration of BV-2 microglial cells. • S100A8/A9 induces release of pro-inflammatory factors and chemokines by activating the NF-κB signaling pathway. • S100A8/A9 activated BV-2 microglial cells exacerbates OPC damage. Abstract S100A8/A9, a heterodimer complex composed of calcium-binding proteins S100A8 and S100A9, is significantly increased in the serum of multiple sclerosis (MS) patients. Relevant reports have revealed that MS pathology is commonly associated with the activation of microglial cells and the damage of oligodendrocyte precursor cells (OPCs). Moreover, microglia activation following stimulation increases the expression of pro-inflammatory cytokines, such as interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α), which further exacerbate the damage to OPCs. In this study, we were the first to confirm that S100A8/A9 treatment induced the activation, proliferation and migration of the murine microglia cell line BV-2; moreover, this treatment caused the cells to switch from an anti-inflammatory activated (M2) phenotype to a pro-inflammatory activated (M1) phenotype. Meanwhile, the level of the phosphorylated nuclear factor-κB (p-NF-κB) P65 protein was remarkably elevated, and the production of pro-inflammatory factors (IL-1β, TNF-α, MMP-9) and chemokines (CCL2, CCL3, CXCL10) was also increased in the S100A8/A9-treated BV-2 microglial cells. Inhibition of NF-κB P65 phosphorylation reversed the effects of S100A8/A9 on the production of pro-inflammatory factors and chemokines. We also explored the effects of S100A8/A9 and S100A8/A9-activated BV-2 microglial cells on the viability of OPCs. The results showed that both the S100A8/A9 complex and the conditioned medium (CM) of the S100A8/A9-activated BV-2 microglial cells resulted in OPC apoptosis, which was more pronounced in the case of the CM treatment. However, OPC apoptosis in the CM group was obviously decreased through the inhibition of NF-κB p65 phosphorylation. This study indicates that S100A8/A9 induces the activation of BV-2 microglial cells and promotes the production of pro-inflammatory factors by activating the NF-κB signaling pathway, which further exacerbates OPC damage. [ABSTRACT FROM AUTHOR]

One undescribed C 40 terpenoid, calomacroquinoic acid; four undescribed diterpenes, 5α,6α-epoxy-7α-hydroxyferruginol, 15-ethoxysugiol, 7-methoxy-6,7-secoabieta-8,11,13-triene-6,12-diol, and ethyl 7,8-secoabieta-11,14-dioxo-7-ate; two compounds isolated from Nature for the first time, 6β,7α-dihydroxyferruginol and 12-O-methyltaxochinon; and six known compounds were successfully identified from the bark of Taiwan incense cedar Calocedrus formosana. Structures of all isolates were elucidated by physical data (appearance, ultraviolet, infrared, specific rotation, and X-ray) and spectroscopic data (1D and 2D nuclear magnetic resonance, and high-resolution electron ionization mass spectrometry). The biosynthetic pathway of calomacroquinoic acid is also described in the current study. Nitric oxide production in lipopolysaccharide (LPS)-stimulated BV-2 microglia cells was inhibited by 6,7-dehydroferruginol, 7α,11-dihydroxy-12-methoxy-8,11,13-abietriene, and trans-communic acid. Altogether, the bark of C. formosana possessed several potential natural therapeutics against inflammation-related neuronal diseases. [Display omitted] • Seven undescribed and six known compounds were isolated from C. formosana. • The absolute configuration of calomacroquinoic acid was elucidated by X-ray crystallographic data. • Calomacroquinoic acid is a rare tetraterpene combined a sesquiterpene with a sesterterpene. • The proposed biosynthetic pathway of calomacroquinoic acid was also described. • Three compounds showed anti-neuroinflammatory properties in BV-2 cells. [ABSTRACT FROM AUTHOR]

The ethyl acetate fraction from the seeds of Swietenia macrophylla (SMEAF) was studied for anti-inflammatory properties using lipopolysaccharide (LPS)-induced BV-2 microglia. SMEAF significantly attenuated the LPS-induced production of nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6). SMEAF inhibited nuclear translocation of nuclear factor-kappa B (NF-κB) via the attenuation of IκBα phosphorylation. Moreover, SMEAF markedly suppressed phosphorylation of Akt, p38 Mitogen-activated protein kinase (MAPK) and Extracellular signal-regulated kinase 1/2 (ERK1/2) in LPS-induced BV-2 cells. Treatment with specific inhibitors for Akt, NF-κB, p38 and ERK1/2 resulted in the attenuation of iNOS and COX-2 protein expression. These findings indicated that SMEAF possesses anti-inflammatory activities in BV-2 cells by modulating LPS-induced pro-inflammatory mediator production via the inhibition of Akt-dependent NF-κB, p38 MAPK and ERK1/2 activation. These results further advocate the potential use of S. macrophylla as nutraceutical for the intervention of neurodegenerative and neuroinflammatory disorders. [ABSTRACT FROM AUTHOR]

In the current study, we evaluated the anti-inflammatory effects of Lonicera japonica THUNB. (LJ) and its underlying molecular mechanism in lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. Our results indicated that LJ significantly inhibits LPS-stimulated production of nitric oxide (NO) and prostaglandin E2 (PGE2). In addition, LJ inhibited inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at both the protein and mRNA levels. In LPS-stimulated BV-2 microglial cells, LJ inhibited proinflammatory cytokines and chemokines, tumor necrosis factor- α (TNF- α), interleukin-1 β (IL-1 β), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9) enzymatic activities, and/or mRNA expression, as well as reactive oxygen species (ROS) production. LJ significantly suppressed activation of nuclear factor- κB (NF- κB) and its translocation from the cytosol to the nucleus and suppressed the DNA-binding activity of NF- κB. Furthermore, LJ significantly inhibited phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase 1/2 (ERK 1/2), p38 mitogen-activated protein kinases (MAPKs), phosphatidylinositol 3-kinases (PI3K)/Akt, and Janus kinase 1 (JAK1)/signal transducer and activator of transcription (STAT)1/3. Collectively, our findings indicated that the antineuroinflammatory properties of LJ in LPS-induced BV-2 microglial cells is due to downregulation of proinflammatory cytokines and chemokines downstream of inhibition of NF- κB activation. [ABSTRACT FROM AUTHOR]

Abstract: Increasing evidence suggests that tangeretin, a flavonoid from citrus fruit peels, exhibits anti-inflammatory properties and neuroprotective effects in animal disease models. However, the underlying molecular mechanisms are not clearly understood. In this study, we investigated whether tangeretin suppresses excessive microglial activation implicated in the resulting neurotoxicity following stimulation with lipopolysaccharide (LPS) in primary rat microglia and BV-2 microglial cell culture models. The results showed that tangeretin decreased the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), in a dose-dependent manner. Additionally, it inhibited the LPS-induced expression of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) (examined at the protein level) as well as TNF-α, IL-1β, and IL-6 (examined at the mRNA level) in microglial cells. To explore the possible mechanisms underlying these inhibitions by tangeretin, we examined the mitogen-activated protein kinase (MAPK) protein levels and the NF-κB protein signaling pathway. Tangeretin clearly inhibited LPS-induced phosphorylation of ERK, N-terminal Kinase (JNK), and p38. In addition, tangeretin markedly reduced LPS-stimulated phosphorylation of IκB-α and IKK-β, as well as the nuclear translocation of the p65 subunit of pro-inflammatory transcription factor NF-κB. Taken together, these results support further exploration of the therapeutic potential and molecular mechanism of tangeretin in relation to neuroinflammation and neurodegenerative diseases accompanied by microglial activation. [Copyright &y& Elsevier]

Abstract: As the first and main form of active immune defense in the central nervous system, microglial cells usually exhibit complicated intracellular calcium (Ca2+) activity that can regulate the downstream components of signaling cascades. In the present work, spontaneous oscillations of the cytosolic calcium concentration ([Ca2+]c) in multi-BV-2 microglial cells were observed by video microscopy. These cells exhibited random spikes of Ca2+ oscillations. Cross-correlation analysis of the temporal dependence of the oscillations indicated the existence of cell–cell communication mediated by extracellular messengers. Numerical simulations based on a simple mathematical model suggested that these communications could induce random spikes of spontaneous Ca2+ oscillations in the multi-cell system. Short-time imaging analysis of random spikes in different regions of a single cell showed that spontaneous Ca2+ oscillations resulted from Ca2+ wave generated by other cells as well as from calcium elevation inside the cell. Taken together, our data demonstrate that cell–cell communication existed between the BV-2 microglial cells in vitro and further resulted in the random spikes of spontaneous Ca2+ oscillations. [Copyright &y& Elsevier]

Recent studies have shown that oligomeric amyloid-β (oAβ) peptide can potentially activate microglia in addition to inducing more potent neurotoxicity compared with fibrillar Aβ (fAβ); however, its mechanisms of action remain unclear. This study was designed to investigate the possible mechanisms involved in the microglial activation induced by oAβ in BV-2 microglial cells. The results showed that oAβ induced activated properties of microglia, including higher proliferative capacity as well as increased production of reactive oxygen species, nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β). NADPH oxidase inhibitors [diphenylene iodonium (DPI) and apocynin (4-hydroxy-3-methoxy-acetophenone)] prevented the microglial activation induced by oAβ, suggesting that NADPH oxidase activation was involved in microglial activation. In addition, TNF-α and IL-1β, which are massively released by activated microglia, significantly induced the activation of microglia, thereby resulting in the production of NO and proliferation of microglia, respectively. These effects could be inhibited by diphenylene iodonium and apocynin, indicating a self-cycle regulated by NADPH oxidase in microglial activation in response to oAβ. In conclusion, microglial activation induced by oAβ is possibly mediated by NADPH oxidase, suggesting that oAβ, which is normally considered a neurotoxin, may also lead to indirect neuronal damage through the pro-inflammation activation of microglia in Alzheimer's disease and that NADPH oxidase could be a potential target to prevent oAβ-induced inflammatory neurodegeneration. [ABSTRACT FROM AUTHOR]

Abstract: Brain protection is essential during neonatal and pediatric cardiac surgery. Deep hypothermia is still the most important method for achieving neuroprotection during cardiopulmonary bypass. Previously, we could demonstrate that deep hypothermia induces substantial cytotoxicity in brain cells as well as increased release of the pro-inflammatory cytokine interleukin-6 (IL-6), which plays an important role in neuroprotection and neuroregeneration. Deep hypothermia is also associated with increased levels of the astrocytic protein S100B in the serum and cerebrospinal fluid of patients. Since S100B may modulate pro-inflammatory cytokines and may stimulate neurite outgrowth, we have tested the hypothesis that nanomolar concentrations of S100B may increase IL-6 release from brain cells and support axonal outgrowth from organotypic brain slices under hypothermic conditions. S100B administration substantially reduced neuronal and glial cytotoxicity under hypothermic conditions. In the presence of S100B hypothermia-induced IL-6 release in primary astrocytes was significantly increased but reduced in BV-2 microglial cells and primary neurons. Surprisingly, deep hypothermia increased axonal outgrowth from brain slices and – in contrast to our hypothesis – this hypothermia-induced neurite outgrowth was inhibited by S100B. These data suggest that S100B differentially influences cytokine release and cytotoxicity from distinct brain cells and may inhibit neuroregeneration by suppressing hypothermia-induced axonal outgrowth. [Copyright &y& Elsevier]

Abstract Under normal and pathological conditions, brain cells release nucleotides that regulate a wide range of cellular responses due to activation of P2 nucleotide receptors. In this study, the effect of extracellular nucleotides on IFNγ-induced NO release in murine BV-2 microglial cells was investigated. BV-2 cells expressed mRNA for metabotropic P2Y and ionotropic P2X receptors. Among the P2 receptor agonists tested, ATP, ADP, 2′,3′-O-(4-benzoylbenzoyl)-ATP (BzATP), and 2-methylthio-ATP (2-MeSATP), but not UTP, enhanced IFNγ-induced iNOS expression and NO production, suggesting that the uridine nucleotide receptors P2Y[sub 2] and P2Y[sub 6] are not involved in this response. U0126, an antagonist for MEK1/2, a kinase that phosphorylates the extracellular signal-regulated kinases ERK1/2, decreased IFNγ-induced NO production. BzATP, a potent P2X[sub 7] receptor agonist, was more effective than ATP, ADP, or 2-MeSATP at enhancing IFNγ-induced ERK1/2 phosphorylation. Consistent with activation of the P2X[sub 7] receptor, periodate-oxidized ATP, a P2X[sub 7] receptor antagonist, and suramin, a non-specific P2 receptor antagonist, inhibited the effect of ATP or BzATP on IFNγ-induced NO production, whereas pyridoxal-phosphate-6-azophenyl-2′,4′-disulfonic acid (PPADS), an antagonist of several P2X receptor subtypes, was ineffective. These results suggest that activation of P2X[sub 7] receptors may contribute to inflammatory responses in microglial cells seen in neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Microglial cells clear the brain of pathogens and harmful debris, including amyloid-β (Aβ) deposits that are formed during Alzheimer's disease (AD). We studied the expression of Msr1, Ager and Cd36 receptors involved in Aβ uptake and expression of Cd33 protein, which is considered a risk factor in AD. The effect of silver nanoparticles (AgNP) and cadmium telluride quantum dots (CdTeQD) on the expression of the above receptors and Aβ uptake by microglial cells was investigated. Absorption of Aβ and NP was confirmed by confocal microscopy. AgNP, but not CdTeQD, caused a decrease in Aβ accumulation. By using a specific inhibitor—polyinosinic acid—we demonstrated that Aβ and AgNP compete for scavenger receptors. Real-time PCR showed up-regulation of Cd33 and Cd36 gene expression after treatment with CdTeQD for 24 h. Analysis of the abundance of the receptors on the cell surface revealed that AgNP treatment significantly reduced the presence of Msr1, Cd33, Ager and Cd36 receptors (6 and 24 h), whereas CdTeQD increased the levels of Msr1 and Cd36 (24 h). To summarize, we showed that AgNP uptake competes with Aβ uptake by microglial cells and consequently can impair the removal of the aggregates. In turn, CdTeQD treatment led to the accumulation of proinflammatory Cd36 protein on the cell surface. [ABSTRACT FROM AUTHOR]

• Geniposide inhibited cell death in BV-2 microglial cells. • Geniposide regulated inflammatory cytokines in BV-2 microglial cells. • Geniposide induced autophagy and attenuated NLRP3 inflammasome activation. The nod-like receptor protein 3 (NLRP3) inflammasome has a critical role in cerebral ischemia. Autophagy may cause microglial inflammatory response or stimulate microglial function. The evidences clarify a direct crosstalk between autophagy and NLRP3. Geniposide could protect neurons or PC-12 cells against cerebral ischemic injury. However, a detailed understanding of molecular mechanisms on geniposide is still unclear. This study aimed to evaluate whether geniposide could inhibit the expression and activation of NLRP3 inflammasome in BV-2 microglial cells following oxygen–glucose deprivation/reoxygenation (OGD/R) and assessed whether autophagy is involved in this process. We used OGD/R model in BV2 microglial cells in order to mimic the ischemic reperfusion injury. The NLRP3 shRNA and autophagy inhibitor (3-MA) were used to suppress NLRP3 inflammation activation and autophagy. The results demonstrated geniposide decreased cell death and the levels of NLRP3, ASC, cleaved- caspase-1 and IL-1β, whereas significantly increased the conversion of LC3 and Beclin-1 expression, decreased the expression of P62. Taken together, our results suggested that the effect of geniposide could be ascribed to the reduction of the level of inflammatory cytokines via inhibiting the activation and expression of NLRP3 inflammasome and increasing autophagic activity following OGD/R in BV-2 microglial cells. We provided a new understanding of geniposide in neuroprotection by activating autophagy and promoting anti-inflammation inhibiting NLRP3 inflammasome in microglial cells. It might be helpful for geniposide on effective therapeutic strategies in ischemic stroke. [ABSTRACT FROM AUTHOR]

One new pseudoguaianolide (1), one new megastigmane (6), and one new ent -abietane diterpene (9), together with seven known compounds (2 – 5 , 7 , 8 , and 10) were isolated from the aerial parts of Euphorbia thymifolia. The structures of the new compounds and their relative configurations were determined by spectroscopic data analysis. The absolute configurations of compounds 1 , 6 , and 9 were determined by single-crystal X-ray crystallographic analysis, modified Mosher's method and calculated ECD experiment, respectively. All compounds were tested for their inhibitory effects against LPS-induced NO production in BV-2 microglial cells, and pseudoguaianolides (1 – 5) showed significant activity with IC 50 values of 0.41–15.32 μM. Unlabelled Image [ABSTRACT FROM AUTHOR]

Two previously undescribed guaiane-type sesquiterpenes (1 and 2), a pair of new salvialane-type sesquiterpenes (3a and 3b), together with 11 known compounds were isolated and purified from the rhizomes of Curcuma kwangsiensis. Their structures were elucidated by the extensive spectroscopic data (1D- and 2D-NMR) analysis. All the isolated compounds were assessed for their anti-neuroinflammatory activity by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells in vitro assay, and the isolates 3 and 11 showed anti-neuroinflammatory activity with IC 50 values of 1.85 and 20.05 μm, respectively., (© 2019 Wiley-VHCA AG, Zurich, Switzerland.)

Microglial cells play important roles in neurodegenerative diseases including peroxisomal leukodystrophies. The BV-2 murine immortalized cells are widely used in the context of neurodegenerative researches. It is therefore important to establish the expression pattern of peroxisomal proteins by flow cytometry in these cells. So, the expression pattern of various peroxisomal transporters (Abcd1, Abcd2, Abcd3) contributing to peroxisomal β-oxidation was evaluated on BV-2 cells by flow cytometry and complementary methods (fluorescence microscopy, and RT-qPCR). By flow cytometry a strong expression of peroxisomal proteins (Abcd1, Abcd2, Abcd3) was observed. These data were in agreement with those obtained by fluorescence microscopy (presence of numerous fluorescent dots in the cytoplasm characteristic of a peroxisomal staining pattern) and RT-qPCR (high levels of Abcd1, Abcd2, and Abcd3 mRNAs). Thus, the peroxisomal proteins (Abcd1, Abcd2, Abcd3) are expressed in BV-2 cells, and can be analyzed by flow cytometry.

This study was designed to evaluate the pharmacological effects of Vaccinium bracteatum Thunb. methanol extract (VBME) on microglial activation and to identify the underlying mechanisms of action of these effects. The anti-inflammatory properties of VBME were studied using lipopolysaccharide (LPS)-stimulated BV-2 microglial cells. We measured the production of nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase (COX)-2, prostaglandin E₂ (PGE₂), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6) as inflammatory parameters. We also examined the effect of VBME on intracellular reactive oxygen species (ROS) production and the activity of nuclear factor-kappa B p65 (NF-κB p65). VBME significantly inhibited LPS-induced production of NO and PGE2 and LPS-mediated upregulation of iNOS and COX-2 expression in a dose-dependent manner; importantly, VBME was not cytotoxic. VBME also significantly reduced the generation of the pro-inflammatory cytokines TNF-α, IL-1β, and IL-6. In addition, VBME significantly dampened intracellular ROS production and suppressed NF-κB p65 translocation by blocking IκB-α phosphorylation and degradation in LPS-stimulated BV2 cells. Our findings indicate that VBME inhibits the production of inflammatory mediators in BV-2 microglial cells by suppressing NF-κB signaling. Thus, VBME may be useful in the treatment of neurodegenerative diseases due to its ability to inhibit inflammatory mediator production in activated BV-2 microglial cells.

In the present study, we investigated the anti-inflammatory properties of Eucommia ulmoides Oliv. Bark. (EUE) in lipopolysaccharide (LPS)-stimulated microglial BV-2 cells and found that EUE inhibited LPS-mediated up-regulation of pro-inflammatory response factors. In addition, EUE inhibited the elevated production of pro-inflammatory cytokines, mediators, and reactive oxygen species (ROS) in LPS-stimulated BV-2 microglial cells. Subsequent mechanistic studies revealed that EUE suppressed LPS-induced phosphorylation of mitogen-activated protein kinases (MAPKs), phosphoinositide-3-kinase (PI3K)/Akt, glycogen synthase kinase-3β (GSK-3β), and their downstream transcription factor, nuclear factor-kappa B (NF-κB). EUE also blocked the nuclear translocation of NF-κB and inhibited its binding to DNA. We next demonstrated that EUE induced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and upregulated heme oxygenase-1 (HO-1) expression. We determined that the significant up-regulation of HO-1 expression by EUE was a consequence of Nrf2 nuclear translocation; furthermore, EUE increased the DNA binding of Nrf2. In contrast, zinc protoporphyrin (ZnPP), a specific HO-1 inhibitor, blocked the ability of EUE to inhibit NO and PGE₂ production, indicating the vital role of HO-1. Overall, our results indicate that EUE inhibits pro-inflammatory responses by modulating MAPKs, PI3K/Akt, and GSK-3β, consequently suppressing NF-κB activation and inducing Nrf2-dependent HO-1 activation.