Association of NF-κB and AP-1 with MMP-9 Overexpression in 2-Chloroethanol Exposed Rat Astrocytes

Modulation of autophagy and apoptosis can contribute to the anticancer effect of Abemaciclib/Celecoxib combination in colon cancer cells

Drug resistance and recurrence represent a great challenge in colorectal cancer management, highlighting the urgent need for novel therapeutics. Our objective is to evaluate the influence of Abemaciclib, Celecoxib, and their combination on both the autophagic and apoptotic machinery in an attempt to unravel the interplay between them in HCT-116 and Caco-2 cell lines. The MTT assay was used to assess the GI50 of the drugs. ELIZA was used to determine the protein levels of Beclin-1, LC3, Cox-2, and Bcl-2. Active Caspase-3 was determined by a colorimetric assay. Gene expression levels of ATG5, LC3, Beclin-1, and p62 were assessed by quantitative real-time PCR. In HCT-116 cells, the GI50s for Abemaciclib and Celecoxib were 15.86 and 92.67 μM, respectively, while for Caco-2 cells, the GI50s were 7.85 and 49.02 μM for Abemaciclib and Celecoxib, respectively. Upon treatment of HCT-116 and Caco-2 cells with Abemaciclib, Celecoxib, and their combinations, ATG5, p62, LC3, and Beclin-1 gene expression levels were up-regulated. The protein levels of Beclin-1, LC3, and Caspase-3 were significantly increased, while Bcl-2 was decreased in both cell lines due to single and combined treatments. Both drugs, either alone or in combination, decreased the migration ability of the cells in both cell lines. To conclude, the treatment protocol has the potential to induce cell cycle arrest, diminish the potentiality of cells for migration, and initiate apoptotic and autophagic cell death. Further research is recommended to unravel the potential antitumor effects of Abemaciclib/Celecoxib combination in different cancer types.

The Role and Therapeutic Implications of Inflammation in the Pathogenesis of Brain Arteriovenous Malformations

Brain arteriovenous malformations (bAVMs) are focal vascular lesions composed of abnormal vascular channels without an intervening capillary network. As a result, high-pressure arterial blood shunts directly into the venous outflow system. These high-flow, low-resistance shunts are composed of dilated, tortuous, and fragile vessels, which are prone to rupture. BAVMs are a leading cause of hemorrhagic stroke in children and young adults. Current treatments for bAVMs are limited to surgery, embolization, and radiosurgery, although even these options are not viable for ~20% of AVM patients due to excessive risk. Critically, inflammation has been suggested to contribute to lesion progression. Here we summarize the current literature discussing the role of the immune system in bAVM pathogenesis and lesion progression, as well as the potential for targeting inflammation to prevent bAVM rupture and intracranial hemorrhage. We conclude by proposing that a dysfunctional endothelium, which harbors the somatic mutations that have been shown to give rise to sporadic bAVMs, may drive disease development and progression by altering the immune status of the brain.

Cytotoxic Activity, Anti-Migration and In Silico Study of Black Ginger (Kaempferia parviflora) Extract against Breast Cancer Cell

Metastatic breast cancer remains the leading cause of death in women worldwide. This condition necessitates extensive research to find an effective treatment, one of which is the natural medicine approach. Kaempferia parviflora (KP) is a plant believed to possess anticancer properties. Therefore, this study aims to determine KP's bioactive compound, cytotoxic, and anti-migration activity in the highly metastatic breast cancer cell line model 4T1, also in the breast cancer cell model MCF-7 and noncancerous cell line NIH-3T3. Maceration with ethanol (EEKP) and infusion with distilled water (EWKP) was used for extraction. The MTT assay was used to test for cytotoxicity, and the scratch wound healing assay was used to test for the inhibition of migration. Phytochemical profiling of EEKP was performed using UHPLC-MS, and the results were studied for in silico molecular docking. Result showed that EEKP had a better cytotoxic activity than EWKP with an IC₅₀ value of 128.33 µg/mL (24 h) and 115.09 µg/mL (48 h) on 4T1 cell line, and 138.43 µg/mL (24 h) and 124.81 µg/mL (48 h) on MCF-7 cell line. Meanwhile, no cytotoxic activity was observed at concentrations ranging from 3-250 µg/mL in NIH-3T3. EEKP also showed anti-migration activity in a concentration of 65 µg/mL. Mass Spectrophotometer (MS) structures from EEKP are 5-Hydroxy-7,4'-dimethoxyflavanone (HDMF), 5-Hydro-7,8,2'-trimethoxyflavanone (HTMF), Retusine, and Denbinobin. The in silico docking was investigated for receptors Bcl-2, Bcl-XL, ERK2, and FAK, as well as their activities. In silico result indicates that HTMF and denbinobin are bioactive compounds responsible for EEKP's cytotoxic and anti-migration activity. These two compounds and standardized plant extract can be further studied as potential breast cancer treatment candidates.

Metal Complexes as Promising Matrix Metalloproteinases Regulators

Nowadays, cancers and dementia, such as Alzheimer's disease, are the most fatal causes of death. Many studies tried to understand the pathogenesis of those diseases clearly and develop a promising way to treat the diseases. Matrix metalloproteinases (MMPs) have been reported to be involved in the pathology of cancers and AD through tumor cell movement and amyloid degradation. Therefore, control of the levels and actions of MMPs, especially MMP-2 and MMP-9, is necessary to care for and/or cure cancer and AD. Various molecules have been examined for their potential application as regulators of MMPs expression and activity. Among the molecules, multiple metal complexes have shown advantages, including simple synthesis, less toxicity and specificity toward MMPs in cancer cells or in the brain. In this review, we summarize the recent studies and knowledge of metal complexes (e.g., Pt-, Ru-, Au-, Fe-, Cu-, Ni-, Zn-, and Sn-complexes) targeting MMPs and their potentials for treating and/or caring the most fatal human diseases, cancers and AD.

Inhibitory effects of mixed flavonoid supplements on unraveled DSS-induced ulcerative colitis and arthritis

Introduction: The mixed flavonoid supplement (MFS) [Trimethoxy Flavones (TMF) + epigallocatechin-3-gallate (EGCG)] can be used to suppress inflammatory ulcers as an ethical medicine in Ayurveda. The inflammation of the rectum and anal regions is mostly attributed to nuclear factor kappa beta (NF-κB) signaling. NF-κB stimulates the expression of matrix metalloproteinase (MMP9), inflammatory cytokines tumor necrosis factor (TNF-α), and interleukin-1β (IL-1β). Although much research targeted the NF-κB and MMP9 signaling pathways, a subsequent investigation of target mediators in the inflammatory ulcer healing and NF-κB pathway has not been done. Methods: The docking studies of compounds TMF and EGCG were performed by applying PyRx and available software to understand ligand binding properties with the target proteins. The synergistic ulcer healing and anti-arthritic effects of MFS were elucidated using dextran sulfate sodium (DSS)-induced colon ulcer in Swiss albino rats. The colon mucosal injury was analyzed by colon ulcer index (CUI) and anorectic tissue microscopy. The IL-1β, tumor necrosis factor (TNF-α), and the pERK, MMP9, and NF-κB expressions in the colon tissue were determined by ELISA and Western blotting. RT-PCR determined the mRNA expression for inflammatory marker enzymes. Results: The docking studies revealed that EGCG and TMF had a good binding affinity with MMP9 (i.e., -6.8 and -6.0 Kcal/mol) and NF-kB (-9.4 and 8.3 kcal/mol). The high dose MFS better suppressed ulcerative colitis (UC) and associated arthritis with marked low-density pERK, MMP9, and NF-κB proteins. The CUI score and inflammatory mediator levels were suppressed with endogenous antioxidant levels in MFS treated rats. Conclusion: The MFS effectively unraveled anorectic tissue inflammation and associated arthritis by suppressing NF-κB-mediated MMP9 and cytokines.

In-vivo and in-silico studies of Eucalyptus kino polyphenolics: outstanding activity in quenching solid liver tumors through inhibition of MMP-9 and TGF-β gene expression

As a result of our continuous research efforts to investigate the molecular mechanisms of Eucalyptus kino polyphenolics for healing liver solid tumors, in-vivo histopathological studies of the solid tumor tissues and in-silico molecular docking were carried out. Histopathology of female mice treated with a dose of 200 mg/kg Eucalyptus kino methanolic extract in combination with low level ionising γ-radiation (0.25 Gy) recovered a near-to-normal histological structure revealing a substantial number of cells with hyper-chromachia in nuclei, fibroblast lobules and necrotic cells. Analysis for matrix metalloproteinase-9 (MMP-9) by Western blot and also molecular docking study were conducted to evaluate and rank the potential of the individual components dominated in the extract to inhibit MMP-9 and TGF-β. The current study presents new lead compounds for the design of novel MMP-9 and TGF-β strong inhibitors of natural origin.

Disturbance of glutamate metabolism and inhibition of CaM-CaMKII-CREB signaling pathway in the hippocampus of mice induced by 1,2-dichloroethane exposure

1,2-Dichloroethane (1,2-DCE) is a highly toxic neurotoxicity, and the brain tissue is the main target organ. At present, long-term exposure to 1,2-DCE has been shown to cause cognitive dysfunction in some studies, but the mechanism is not clear. The results of this study showed that long-term 1,2-DCE exposure decreased learning and memory abilities in mice and impaired the structure and morphology of neurons in the hippocampal region. Moreover, except for the mRNA level of PAG, the enzymatic activities and protein levels of GS and PAG, as well as the mRNA level of GS were inhibited. With increasing dose of exposure, the protein and mRNA expression of GLAST and GLT-1 also decreased. Contrarily, there were protein and mRNA expression upregulation of GluN1, GluN2A and GluN2B in the hippocampus, as well as increased levels of extracellular Glu and intracellular Ca²⁺. In addition, 1,2-DCE exposure also downregulated the protein expression levels of CaM, CaMKII and CREB. Taken together, our results suggest that long-term 1,2-DCE exposure impairs the learning and memory capacity in mice, which may be attributed to the disruption of Glu metabolism and the inhibition of CaM- CaMKII-CREB signaling pathway in the hippocampus.

Nuclear factor kappa B signaling within the rat nucleus accumbens core sex-dependently regulates cue-induced cocaine seeking and matrix metalloproteinase-9 expression

Chronic drug self-administration and withdrawal are associated with distinct neuroimmune adaptations that may increase drug craving and relapse vulnerability in humans. The nuclear factor kappa-B (NF-κB) pathway is a critical regulator of many immune- and addiction-related genes such as the extracellular matrix enzyme matrix metalloproteinase-9 (MMP-9), which is a known modulator of learning, memory, and synaptic plasticity. While some studies suggest striatal NF-κB signaling may regulate drug-conditioned behavior, no studies to date have examined whether NF-κB signaling within the nucleus accumbens core (NAc core) alters downstream neuroimmune function and cue-motivated cocaine seeking following a period of forced abstinence, whether any effects are specific to cocaine over other reinforcers, or whether sex differences exist. Here, we examined whether viral-mediated knockdown of the p65 subunit of NF-κB within the NAc core would alter MMP-9 expression and cue-induced cocaine- and sucrose-seeking behavior following a period of forced abstinence in male and female rats. We demonstrate that NAc core p65 knockdown results in a significant decrease in cue-induced cocaine seeking in males but not females. This effect was specific to cocaine, as p65 knockdown did not significantly affect cue-induced sucrose seeking in either males or females. Moreover, we demonstrate that males express higher levels of MMP-9 within the NAc core and nucleus accumbens shell (NAcSh) compared to females, and that p65 knockdown significantly decreases MMP-9 in the NAc core of males but not females among cocaine cue-exposed animals. Altogether, these results suggest that NAc core NF-κB signaling exerts modulatory control over cue-motivated drug-seeking behavior and downstream neuroimmune function in a sex-specific manner. These findings highlight the need to consider sex as an important biological variable when examining immunomodulatory mechanisms of cocaine seeking.

1,2-Dichloroethane induces cortex demyelination by depressing myelin basic protein via inhibiting aquaporin 4 in mice

1,2-Dichloroethane (1,2-DCE) is a pervasive environmental pollutant, and overexposure to this hazardous material causes brain edema and demyelination in humans. We found that 1,2-DCE inhibits aquaporin 4 (AQP4) and is a primary pathogenic effector of 1,2-DCE-induced brain edema in animals. However, AQP4 down-regulation's link with cortex demyelination after 1,2-DCE exposure remains unclear. Thus, we exposed wild-type (WT) CD-1 mice and AQP4 knockout (AQP4-KO) mice to 0, 100, 350 and 700 mg/m³ 1,2-DCE by inhalation for 28 days. We applied label-free proteomics and a cell co-culture system to elucidate the role of AQP4 inhibition in 1,2-DCE-induced demyelination. The results showed that 1,2-DCE down-regulated AQP4 in the WT mouse cortexes. Both 1,2-DCE exposure and AQP4 deletion induced neurotoxicity in mice, including increased brain water content, abnormal pathological vacuolations, and neurobehavioral damage. Tests for interaction of multiple regression analysis highlighted different effects of 1,2-DCE exposure level depending on the genotype, indicating the core role of AQP4 in regulation on 1,2-DCE-caused neurotoxicity. We used label-free quantitative proteomics to detect differentially expressed proteins associated with 1,2-DCE exposure and AQP4 inhibition, and identified down-regulation in myelin basic protein (MBP) and tyrosine-protein kinase Fyn (FYN) in a dose-dependent manner in WT mice but not in AQP4-KO mice. 1,2-DCE and AQP4 deletion separately resulted in demyelination, as detected by Luxol fast blue staining, and manifested as disordered nerve fibers and cavitation in the cortexes. Western blot and immunofluorescence confirmed the decreased AQP4 in the astrocytes and the down-regulated MBP in the oligodendrocytes by 1,2-DCE exposure and AQP4 inhibition, respectively. Finally, the co-culture results of SVG p12 and MO3.13 cells showed that 1,2-DCE-induced AQP4 down-regulation in the astrocytes was responsible for demyelination, by decreasing MBP in the oligodendrocytes. In conclusion, 1,2-DCE induced cortex demyelination by depressing MBP via AQP4 inhibition in the mice.

Anti-Inflammatory Effects of Rhamnetin on Bradykinin-Induced Matrix Metalloproteinase-9 Expression and Cell Migration in Rat Brain Astrocytes

Bradykinin (BK) has been shown to induce matrix metalloproteinase (MMP)-9 expression and participate in neuroinflammation. The BK/MMP-9 axis can be a target for managing neuroinflammation. Our previous reports have indicated that reactive oxygen species (ROS)-mediated nuclear factor-kappaB (NF-κB) activity is involved in BK-induced MMP-9 expression in rat brain astrocytes (RBA-1). Rhamnetin (RNT), a flavonoid compound, possesses antioxidant and anti-inflammatory effects. Thus, we proposed RNT could attenuate BK-induced response in RBA-1. This study aims to approach mechanisms underlying RNT regulating BK-stimulated MMP-9 expression, especially ROS and NF-κB. We used pharmacological inhibitors and siRNAs to dissect molecular mechanisms. Western blotting and gelatin zymography were used to evaluate protein and MMP-9 expression. Real-time PCR was used for gene expression. Wound healing assay was applied for cell migration. 2',7'-dichlorodihydrofluorescein diacetate (H2DCF-DA) and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) were used for ROS generation and NOX activity, respectively. Promoter luciferase assay and chromatin immunoprecipitation (ChIP) assay were applied to detect gene transcription. Our results showed that RNT inhibits BK-induced MMP-9 protein and mRNA expression, promoter activity, and cell migration in RBA-1 cells. Besides, the levels of phospho-PKCδ, NOX activity, ROS, phospho-ERK1/2, phospho-p65, and NF-κB p65 binding to MMP-9 promoter were attenuated by RNT. In summary, RNT attenuates BK-enhanced MMP-9 upregulation through inhibiting PKCδ/NOX/ROS/ERK1/2-dependent NF-κB activity in RBA-1.

Gaillardin, a potent sesquiterpene lactone induces apoptosis via down-regulation of NF-κβ in gastric cancer cells, AGS and MKN45

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Inula has been traditionally used as folk medicine in treating different illnesses such as kidney stones, urethra infection, jaundice, bronchitis, respiratory diseases and cancer.

AIM OF THE STUDY

Gaillardin, a sesquiterpene lactone isolated from Inula oculus-christi, seems to have great potential as an anti-cancer agent. This study was carried out to evaluate the anti-cancer properties of Gaillardin in gastric cancer cells and also its possible underlying mechanism.

METHODS

The colorimetric MTT assay was used to assess metabolic activity of cells as an indicator of viability and cytotoxicity. Flow cytometry using Annexin V-FITC/PI was applied to detect and quantify the level of apoptosis. Detection of activated caspase-3, as a biochemical marker of apoptosis, was done using caspase-3 assay kit. Activation of NF-κB pathway was determined by western blotting. The mRNA expression levels of NF-κB target genes were measured using quantitative RT-PCR. Moreover, intracellular reactive oxygen species (ROS) production was evaluated.

RESULTS

Gaillardin significantly reduced cell viability in a time and dose-dependent manner. The inhibitory effect of Gaillardin was attributed to induction of apoptosis. Investigation about the underlying mechanism revealed that Gaillardin exerts its action through inhibition of NF-κB activation and subsequently down-regulation of genes (COX-2, MMP-9, TWIST-1, and BCl-2) regulated by NF-κB. Moreover, Gaillardin caused remarkable elevation in ROS production in AGS and MKN45 cells.

CONCLUSION

We provided evidences about the role of NF-κB pathway in the induction of apoptosis by the sesquiterpene lactone Gaillardin in AGS and MKN45 cells for the first time, which suggest Gaillardin could be considered as a promising natural agent for further investigations to identify new potent anticancer drugs in the future.

1,2-Dichloroethane induces apoptosis in the cerebral cortexes of NIH Swiss mice through microRNA-182-5p targeting phospholipase D1 via a mitochondria-dependent pathway

1,2-Dichloroethane (1,2-DCE) is a pervasive environmental pollutant found in ambient and residential air, as well as ground and drinking water. Overexposure to it results in cortex edema, in both animals and humans. 1,2-DCE induces apoptosis in the cerebellum, liver and testes. This promotes the hypothesis that 1,2-DCE may induce apoptosis in the cortex as brain edema progresses. To validate our hypothesis, 40 NIH male mice were exposed to 0, 100, 350, 700 mg/m³ 1,2-DCE by whole-body dynamic inhalation for 28 consecutive days. MicroRNA (miRNA) and mRNA microarray combined with TdT-mediated dUTP nick-end labeling, flow cytometry, and mitochondrial membrane potential (mtΔΨ) measurement were applied to identify the cortex apoptosis pathways' specific responses to 1,2-DCE, in vitro and in vivo. The results showed that 1,2-DCE caused brain edema and increased apoptosis in the mouse cortexes. We confirmed that 1,2-DCE induced increased apoptosis via mitochondrial pathway, both in vitro and in vivo, as evidenced by increased Caspase-3, cleaved Caspase-3, Cytochrome c and Bax expression, and decreased Bcl-2 expression. Additionally, mtΔΨ decreased after 1,2-DCE treatment in vitro. 1,2-DCE exposure increased miR-182-5p and decreased phospholipase D1 (PLD1) in the cerebral cortex of mice. MiR-182-5p overexpression and PLD1 inhibition reduced mtΔΨ and increased astrocyte apoptosis, yet miR-182-5p inhibition alleviated the 1,2-DCE-induced PLD1 down-regulation and the increased apoptosis. Finally, PLD1 was confirmed to be a target of miR-182-5p by luciferase assay. Taken together, our findings indicate that 1,2-DCE exposure induces apoptosis in the cortex via a mitochondria-dependent pathway. This pathway is regulated by a miR-182-5p⊣PLD1 axie.

Screening assessment of trimethoxy flavonoid and - (-)-epigallocatechin-3-gallate against formalin-induced arthritis in Swiss albino rats and binding properties on NF-κB-MMP9 proteins

Background

The isolated trimethoxy flavonoid 4a,5,8,8a-tetrahydro-5-hydroxy-3,7,8-trimethoxy-2-(3,4-dimethoxyphenyl) chromen-4-one (TMF) from methanolic stem extract of T chrysantha (METC) and - (-)-epigallocatechin-3-gallate (EGCG) can be used to suppress acute inflammation and arthritis as an ethical medicine in Ayurveda. The nuclear factor kappa beta (NF-κB) signaling is involved in the expression of inflammatory mediators such as TNF-α and IL-1β. A successive investigation of NF-κB–MMP9 signaling during the production of inflammatory mediators needs to be developed. The docking studies of compounds TMF and EGCG were carried out using Autodock 4.0 and Discovery studio Biovia 2017 software to find out the interaction between ligand and the target proteins. The anti-arthritic potential of TMF, EGCG, and indomethacin was evaluated against formalin-induced arthritis in Swiss albino rats. Arthritis was assessed by checking the mean increase in paw diameter for 6 days via digital vernier caliper. The blood cell counter and diagnostic kits measured the different blood parameters and Rheumatoid factor (RF, IU/mL). The interleukin-1β (IL-1β) and tumor necrosis factor (TNFα) in serum were determined by ELISA, and the pERK, MMP9, and NF-κB expressions in the inflamed tissue were determined by Western blotting, respectively. The mRNA expression for inflammatory marker enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) was determined by qRT-PCR.

Results

Based on grid score, interactions, and IC50 values in molecular docking studies, the TMF and EGCG can be effectively combined with proteins NF-kB and MMP9. The TMF-HD and EGCG-HD better suppressed the acute inflammation and arthritis with marked low-density pERK, MMP9, NF-κB, iNOS, COX-2 levels. The endogenous antioxidant levels were increased in TMF and EGCG treated rats.

Conclusion

The TMF and EGCG effectively unraveled acute inflammation and arthritis by suppressing NF-κB mediated MMP9 and cytokines.

Graphic abstract

Roles of Crosstalk between Astrocytes and Microglia in Triggering Neuroinflammation and Brain Edema Formation in 1,2-Dichloroethane-Intoxicated Mice

We have previously reported that the activation of astrocytes and microglia may lead to the overproduction of proinflammatory mediators, which could induce neuroinflammation and cause brain edema in 1,2-dichloroethane (1,2-DCE)-intoxicated mice. In this research, we further hypothesized that astrocyte–microglia crosstalk might trigger neuroinflammation and contribute to brain edema in 1,2-DCE-intoxicated mice. The present research revealed, for the first time, that subacute intoxication with 1,2-DCE might provoke the proinflammatory polarization of microglia, and pretreatment with minocycline, a specific inhibitor of microglial activation, may attenuate the enhanced protein levels of ionized calcium-binding adapter molecule1 (Iba-1), cluster of differentiation 11b (CD11b), glial fibrillary acidic protein (GFAP), soluble calcium-binding protein 100B (S100B), tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), inducible nitric oxide synthase (iNOS), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), matrix metalloproteinase-9 (MMP-9), Toll-like receptor 4 (TLR4), MyD88, and p-p65, and ameliorate the suppressed protein expression levels of occludin and claudin 5; we also observed changes in water content and made pathological observations on edema in the brains of 1,2-DCE-intoxicated mice. Moreover, pretreatment with fluorocitrate, an inhibitor of reactive astrocytes, could also reverse the alteration in protein expression levels of GFAP, S100B, Iba-1, CD11b, TNF-α, IL-6, iNOS, VCAM-1, ICAM-1, MMP-9, occludin, and claudin 5 in the brain of 1,2-DCE intoxicated mice. Furthermore, pretreatment with melatonin, a well-known anti-inflammatory drug, could also attenuate the above-mentioned changes in the brains of 1,2-DCE-intoxicated mice. Altogether, the findings from this research indicated that microglial activation might play an important role in triggering neuroinflammation, and hence may contribute to brain edema formation; additionally, the findings suggested that molecular crosstalk between reactive astrocytes and activated microglia may amplify the neuroinflammatory reaction, which could induce secondary brain injury in 1,2-DCE-intoxicated mice.

Reactive astrocytes induced by 2-chloroethanol modulate microglia polarization through IL-1β, TNF-α, and iNOS upregulation

The synthetic organic chemical, 1,2-dichloroethane (1,2-DCE), can cause brain edemas under subacute poisoning. Our previous studies indicated that neuroinflammation could be induced due to astrocytes and microglia activation during brain edemas in 1,2-DCE-intoxicated mice. However, the crosstalk between these two glial cells in 1,2-DCE-induced neuroinflammation remained unclear. In this study, primary cultured rat astrocytes and microglia, as well as an immortalized microglia cell line were employed to study the effects of 2-chloroethanol (2-CE, a 1,2-DCE intermediate metabolite in vivo) treated astrocytes on microglia polarization. Our current results revealed that 2-CE treated rat astrocytes were activated through p38 mitogen-activated protein kinase (p38 MAPK)/nuclear factor-κB (NF-κB), and activator protein-1 (AP-1) signaling pathways. Theses pathways were triggered by reactive oxygen species (ROS) produced during 2-CE metabolism. Also, astrocytes were more sensitive to 2-CE effects than microglia. Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and inducible nitric oxide synthase (iNOS) expressions were upregulated in 2-CE-induced reactive astrocytes, enhancing IL-1β, TNF-α, and nitric oxide (NO) excretions, which stimulated microglia polarization. Therefore, the neuroinflammation induced by 1,2-DCE in mice's brains is probably triggered by reactive astrocytes.

Neuroprotective effects of theobromine in transient global cerebral ischemia-reperfusion rat model

Transient global cerebral ischemia (tGCI) is a cerebrovascular disorder characterized by a brief decline in blood flow, neurological deficits, and is often predictive of stroke. Theobromine (TBR) is consumed worldwide in chocolates, tea, and cocoa products. TBR is a natural stimulant and vasoactive alkaloid that may protect against ischemic injury. In this study, neuroprotective potential of theobromine (TBR) was evaluated in 2-vessel occlusion transient global cerebral ischemia-reperfusion (tGCI/R) rat model. Rats were treated with TBR (50, 100 mg/kg, p.o.) for 7 successive days, and subjected to bilateral common carotid artery occlusion (20 min) or sham surgery after last dose of TBR. Severe neurological deficits accompanied by brain infarction, blood-brain barrier abnormalities, and oedema were noted in rats subjected to tGCI/R, and these effects were prevented by TBR. TBR protected against lipid peroxidation and enhanced glutathione level in brain against tGCI/R. TBR pre-treatment for 7 days prevented tGCI/R induced cell death (lactate dehydrogenase, caspase-3), vascular injury (MMP-9), and inflammation (TNF-α, NFκB) in rat whole brain. TBR protected against glutamate excitotoxicity and GABAergic decline in the brain of rats against tGCI/R injury. Findings of this study showed that TBR can alleviate chances of stroke by preventing acute episodes of cerebral ischemia.

High-fat diet exacerbates lead-induced blood-brain barrier disruption by disrupting tight junction integrity

Environmental exposure to lead (Pb) can damage to the central nervous system (CNS) in humans. High-fat diet (HFD) also has been suggested to impair neurocognitive function. Blood-brain barrier (BBB) is a rigorous permeability barrier for maintaining homeostasis of CNS. The damage of BBB caused by tight junctions (TJs) disruption is central to the etiology of various CNS disorders. This study aimed to investigate whether HFD could exacerbate Pb exposure induced the destruction of BBB integrity by TJs disruption. To this end, we measured cell viability assay, trans-endothelial electrical resistance assay, horseradish peroxidase flux measurement, Western blot analysis, and immunofluorescence experiments. The results showed that palmitic acid (PA), the most common saturated fatty acid found in the human body, can increase the permeability of the BBB in vitro which formed in bEnd.3 cells induced by Pb exposure, and decrease the expression of TJs, such as zonula occludins-1 (ZO-1) and occludin. Besides, we found that PA could promote the up-regulation of matrix metalloproteinase (MMP)-9 expression and activate the c-Jun N-terminal kinase (JNK) pathway induced by Pb. MMP-9 inhibitor or JNK inhibitor could increase BBB integrity and up-regulate the expressions of ZO-1 and occludin after treatment, respectively. Moreover, the JNK inhibitor could down-regulate the expression of MMP-9. In conclusion, these results suggested that HFD exacerbates Pb-induced BBB disruption by disrupting TJs integrity. This may be because PA promotes the activation of JNK pathway and then up-regulated the expression of MMP-9 after Pb-exposure. It is suggested that people with HFD exposed to environmental Pb may cause more serious damage to the CNS.

Galectin-1 ameliorates perioperative neurocognitive disorders in aged mice

Introduction

The incidence of perioperative neurocognitive disorders (PND) is higher in the elderly patients undergoing surgery. Microglia activation‐mediated neuroinflammation is one of the hallmarks of PND. Galectin‐1 has been identified as a pivotal modulator in the central nervous system (CNS), while the role of galectin‐1 in PND induced by microglia‐mediated neuroinflammation is still undetermined.

Methods

An exploratory laparotomy model anesthetized with isoflurane was employed to investigate the role of galectin‐1 on PND in aged mice. Open field test and Morris water maze were used to test the cognitive function 3‐ or 7‐days post‐surgery. The activation of microglia in the hippocampus of aged mice was tested by immunohistochemistry. Western blot, enzyme‐linked immunosorbent assay (ELISA), and quantitative real‐time polymerase chain reaction (qRT‐PCR) were employed to elucidate the underlying mechanisms.

Results

Galectin‐1 attenuated the cognitive dysfunction induced by surgery in aged mice and inhibited microglial activity. Moreover, galectin‐1 decreased the expression level of inflammatory proteins (interleukin‐1β, interleukin‐6, and tumor necrosis factor‐α), and prevented neuronal loss in the hippocampus. Galectin‐1 inhibited the inflammation of BV2 microglial cells induced by lipopolysaccharide via decreasing the translocation of NF‐κB p65 and c‐Jun, while this kind of inhibition was rescued when overexpressing IRAK1.

Conclusion

Our findings provide evidence that galectin‐1 may inhibit IRAK1 expression, thus suppressing inflammatory response, inhibiting neuroinflammation, and improving ensuing cognitive dysfunction. Collectively, these findings unveil that galectin‐1 may elicit protective effects on surgery‐induced neuroinflammation and neurocognitive disorders.

Dose-Dependent Inhibitory Effect of Rosuvastatin in Japanese Patients with Acute Myocardial Infarction on Serum Concentration of Matrix Metalloproteinases-INVITATION Trial

Aim: Matrix metalloproteinases (MMPs) play critical roles in acute myocardial infarction (AMI). This trial was conducted to determine the potential effects of higher-dose rosuvastatin on circulating MMP levels in patients with AMI.

Methods: This was a multicenter, open-label, 1:1 randomized, parallel-group study. Patients with AMI were randomly assigned to the appropriate-dose group (10 mg rosuvastatin once daily) or the low-dose group (2.5 mg rosuvastatin once daily) within 24 hours after percutaneous coronary intervention. MMP-2 and MMP-9 levels were measured on day 1 and at week 4, 12, and 24 after enrollment. The primary endpoint was the change in MMP levels at 24 weeks after enrollment. The secondary endpoints were change in MMP levels at day 1 and weeks 4 and 12 after enrollment.

Results: Between August 2017 and October 2018, 120 patients with AMI from 19 institutions were randomly assigned to either the appropriate-dose or the low-dose group. There were 109 patients who completed the 24-week follow-up. The primary endpoint for both MMP-2 and MMP-9 was not significantly different between the two groups. The change in the active/total ratio of MMP-9 at week 12 after baseline was significantly lower in the appropriate-dose group compared with the low-dose group (0.81 [−52.8–60.1]% vs. 70.1 [−14.5–214.2]%, P =0.004), while the changes in MMP-2 were not significantly different between the two groups during the study period.

Conclusions: This study could not demonstrate the superiority of appropriate-dose of rosuvastatin in inhibiting serum MMPs levels in patients with AMI.

Neurovascular inflammation in the pathogenesis of brain arteriovenous malformations

Brain arteriovenous malformations (bAVM) arise as congenital or sporadic focal lesions with a significant risk for intracerebral hemorrhage (ICH). A wide range of interindividual differences is present in the onset, progression, and severity of bAVM. A growing body of gene expression and polymorphism-based research studies support the involvement of localized inflammation in bAVM disease progression and rupture. In this review article, we analyze the altered responses of neural, vascular, and immune cell types that contribute to the inflammatory process, which exacerbates the pathophysiological progression of vascular dysmorphogenesis in bAVM lesions. The cumulative effect of inflammation in bAVM development is orchestrated by various genetic moderators and inflammatory mediators. We also discuss the potential therapies for the treatment of brain AVM by targeting the inflammatory processes and mediators. Elucidating the precise role of inflammation in the bAVM growth and hemorrhage would open novel avenues for noninvasive and effectual causal therapy that may complement the current therapeutic strategies.

Inhibitory effect of cathepsin K inhibitor (ODN-MK-0822) on invasion, migration and adhesion of human breast cancer cells in vitro

Approximately 90% of patients with advanced breast cancer develop bone metastases; an event that results in severe decrease of quality of life and a drastic deterioration in prognosis. Therefore, to increase the survival of breast cancer patients, the development of new therapeutic strategies to impair metastatic process and skeletal complications is critical. Previous studies on the role of cathepsin K (CTSK) in metastatic spreading led to several strategies for inhibition of this molecule such as MIV-711 (Medivir), balicatib and odanacatib (ODN) which were on trial in the past. The present study intended to assess the anti-metastatic efficacy of ODN in breast cancer cells. Human breast cancer cell lines MDA-MB-231 were treated with different concentrations of ODN and performed invasion, adhesion and migration assays and, RT-PCR and western blot to evaluate the effect of ODN on the metastatic potential of breast cancer cells. ODN markedly decreased wound healing cell migration, invasion and adhesion at a dose dependent manner. ODN inhibits cell invasion by decreasing the matrix metalloproteinase (MMP-9) with the upregulation of TIMP-1 expression. ODN effectively inhibited the phosphorylation of extracellular signal-regulated kinase (ERK), p38, and c-Jun N-terminal Kinase (JNK), and blocked the expression of β-integrins and FAK proteins. ODN also significantly inhibited PI3K downstream targets Rac1, Cdc42, paxillin and Src which are critical for cell adhesion, migration and cytoskeletal reorganization. ODN exerts anti-metastatic action through inhibition of signaling pathway for MMP-9, PI3K and MAPK. This indicates potential therapeutic effects of ODN in the treatment of metastatic breast cancer.

Micronized sacchachitin promotes satellite cell proliferation through TAK1-JNK-AP-1 signaling pathway predominantly by TLR2 activation

BACKGROUND

Ganoderma sp., such as Ganoderma tsugae (GT), play an important role in traditional Chinese medicine. Ganoderma sp. contains several constituents, including Sacacchin, which has recently drawn attention because it can not only enhance the repair of muscle damage but also strengthen the muscle enforcement. Although Ganoderma sp. have a therapeutic effect for neuromuscular disorders, the underlying mechanism remains unclear. This study investigated the effect and underlying molecular mechanism of micronized sacchachitin (mSC) on satellite cells (SCs), which are known as the muscle stem cells.

METHODS

The myogenic cells, included SCs (Pax7⁺) were isolated from tibialis anterior muscles of a healthy rat and were cultured in growth media with different mSC concentrations. For the evaluation of SC proliferation, these cultivated cells were immunostained with Pax7 and bromodeoxyuridine assessed simultaneously. The molecular signal pathway was further investigated by using Western blotting and signal pathway inhibitors.

RESULTS

Our data revealed that 200 µg/mL mSC had an optimal capability to significantly enhance the SC proliferation. Furthermore, this enhancement of SC proliferation was verified to be involved with activation of TAK1-JNK-AP-1 signaling pathway through TLR2, whose expression on SC surface was confirmed for the first time here.

CONCLUSION

Micronized sacchachitin extracted from GT was capable of promoting the proliferation of SC under a correct concentration.

Long noncoding RNA MAPKAPK5-AS1 promotes colorectal cancer progression by cis-regulating the nearby gene MK5 and acting as a let-7f-1-3p sponge

BACKGROUND

Long noncoding RNAs (lncRNAs) are considered critical regulators in cancers; however, the clinical significance and mechanisms of MAPKAPK5-AS1 (hereinafter referred to as MK5-AS1) in colorectal cancer (CRC) remain mostly unknown.

METHODS

In this study, quantitative real-time PCR (qPCR) and western blotting were utilized to detect the levels of MK5-AS1, let-7f-1-3p and MK5 (MAPK activated protein kinase 5) in CRC tissues and cell lines. The biological functions of MK5-AS1, let-7f-1-3p and MK5 in CRC cells were explored using Cell Counting Kit-8 (CCK8), colony formation and transwell assays. The potential mechanisms of MK5-AS1 were evaluated by RNA pull-down, RNA immunoprecipitation (RIP), dual luciferase reporter assay, chromatin immunoprecipitation (ChIP) and bioinformatics analysis. The effects of MK5-AS1 and MK5 on CRC were investigated by a xenotransplantation model.

RESULTS

We confirmed that MK5-AS1 was significantly increased in CRC tissues. Knockdown of MK5-AS1 suppressed cell migration and invasion in vitro and inhibited lung metastasis in mice. Mechanistically, MK5-AS1 regulated SNAI1 expression by sponging let-7f-1-3p and cis-regulated the adjacent gene MK5. Moreover, MK5-AS1 recruited RBM4 and eIF4A1 to promote the translation of MK5. Our study verified that MK5 promoted the phosphorylation of c-Jun, which activated the transcription of SNAI1 by directly binding to its promoter.

CONCLUSIONS

MK5-AS1 cis-regulated the nearby gene MK5 and acted as a let-7f-1-3p sponge, playing a vital role in CRC tumorigenesis. This study could provide novel insights into molecular therapeutic targets of CRC.

3,5-Dicaffeoyl-epi-quinic acid inhibits the PMA-stimulated activation and expression of MMP-9 but not MMP-2 via downregulation of MAPK pathway

Matrix metalloproteinases (MMPs), especially MMP-2 and MMP-9, are very important gelatinases that are overexpressed during tumor metastasis. Up to date, several MMP inhibitors have been developed from natural sources as well as organic synthesis. In the present study, the MMP-2 and MMP-9 inhibitory effects of 3,5-dicaffeoyl-epi-quinic acid (DCEQA), a caffeoylquinic acid derivative isolated from Atriplex gmelinii, were investigated in phorbol 12-myristate 13-acetate (PMA)-treated human HT1080 fibrosarcoma cells. Gelatin zymography and immunoblotting showed that DCEQA significantly inhibited the PMA-induced activation and expression of MMP-9 but was not able to show any effect against MMP-2. DCEQA treatment was also shown to upregulate the protein expression of tissue inhibitor of MMP-1 along with decreased MMP-9 protein levels. Moreover, the effect of DCEQA on phosphorylation of mitogen activated protein kinases (MAPKs), analyzed by immunoblotting, indicated the DCEQA inhibited the MMP-9 by downregulation of MAPK pathway. Collectively, current results suggested that DCEQA is a potent MMP-9 inhibitor and can be utilized as lead compound for treatment of pathological complications involving enhanced MMP activity such as cancer metastasis.

BAP31 regulates IRAK1-dependent neuroinflammation in microglia

BACKGROUND

Microglia, the mononuclear immune cells of the central nervous system (CNS), are essential for the maintenance of CNS homeostasis. BAP31, a resident and ubiquitously expressed protein of the endoplasmic reticulum, serves as a sorting factor for its client proteins, mediating the subsequent export, retention, and degradation or survival. Recently, BAP31 has been defined as a regulatory molecule in the CNS, but the function of BAP31 in microglia has yet to be determined. In the present study, we investigated whether BAP31 is involved in the inflammatory response of microglia.

METHODS

This study used the BV2 cell line and BAP31 conditional knockdown mice generated via the Cre/LoxP system. A BAP31 knockdown experiment was performed to elucidate the role of BAP31 in the endogenous inflammatory cytokine production by microglial BV2 cells. A mouse model of lipopolysaccharide (LPS)-induced cognitive impairment was established to evaluate the neuroprotective effect of BAP31 against neuroinflammation-induced memory deficits. Behavioral alterations were assessed with the open field test (OFT), Y maze, and Morris water maze. The activation of microglia in the hippocampus of mice was observed by immunohistochemistry. Western blot, enzyme-linked immunosorbent assay (ELISA), immunofluorescence staining, and reverse transcription quantitative real-time polymerase chain reaction (RT-PCR) were used to clarify the mechanisms.

RESULTS

BAP31 deficiency upregulates LPS-induced proinflammatory cytokines in BV2 cells and mice by upregulating the protein level of IRAK1, which in turn increases the translocation and transcriptional activity of NF-κB p65 and c-Jun, and moreover, knockdown of IRAK1 or use of an IRAK1 inhibitor reverses these functions. In the cognitive impairment animal model, the BAP31 knockdown mice displayed increased severity in memory deficiency accompanied by an increased expression of proinflammatory factors in the hippocampus.

CONCLUSIONS

These findings indicate that BAP31 may modulate inflammatory cytokines and cognitive impairment induced by neuroinflammation through IRAK1, which demonstrates that BAP31 plays an essential role in microglial inflammation and prevention of memory deficits caused by neuroinflammation.

The expression of MAPK signaling pathways in conjunctivochalasis

This study investigated the potential role of MAPK signaling pathways in conjunctivochalasis (CCH). Twenty loose conjunctival biopsy samples from 20 CCH and 15 conjunctival biopsy samples from 15 normal controls (CON) were collected. The conjunctival fibroblasts were cultured in vitro. Immunofluorescence, ELISA, Western blot and reverse transcription-polymerase chain reaction (RT-PCR) were used. Our results showed that the expression of p-ERK, p-JNK, and p-p38 in CCH conjunctiva was significantly higher than that in CON group. The expression of p38 MAPK, JNK, and ERK proteins in CCH fibroblasts was significantly higher than that in CON group. The total expression of MAPK mRNA in CCH fibroblasts was significantly higher than that in CON group. The activated forms of p38 MAPK, JNK, and ERK proteins and mRNAs might up-regulate the expression of MMPs in CCH loose conjunctival tissue and fibroblasts, causing the degradation of collagen fibers and elastic fibers and promoting the occurrence of CCH. Our results deepen the understanding of CCH pathological mechanism.

Upregulation of CYP2E1 expression causes oxidative damage induced by 2-chloroethanol in primary cultured rat astrocytes

Brain edema caused by subacute poisoning with 1,2-dichloroethane (1,2-DCE) has gained much attention during recent years, but its underlying mechanism is poorly understood. As an intermediate metabolite of 1,2-DCE in vivo, 2-chloroethanol (2-CE) can be transformed into chloroacetaldehyde and reactive oxygen species (ROS) through cytochrome P450 2E1 (CYP2E1) mediated metabolism. In previous studies, it was found that CYP2E1 expression is enhanced in the brain of mice treated with 1,2-DCE. This study was designed to verify the roles of CYP2E1 overexpression in 2-CE induced cytotoxicity in rat astrocytes, and the contribution of specific signaling molecules to the upregulation of CYP2E1 expression caused by 2-CE. The results of this study demonstrate that treatment with 2-CE can enhance CYP2E1 protein and mRNA levels, cause an increase in ROS and MDA levels, and higher percentages of apoptotic cells in rat astrocytes. Pretreatment with either diallyl sulfide or vitamin C, the inhibitor of CYP2E1 or scavenger of ROS, respectively, can suppress the levels of CYP2E1 expression, ROS and MDA, ameliorate cell apoptosis, and attenuate phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) in these cells. Additionally, pretreatment with the inhibitor of either ERK1/2 or transcriptional factor specificity protein 1 (SP1) can suppress the CYP2E1 expression, and alleviate the oxidative damage caused to these cells. In conclusion, our findings demonstrate that CYP2E1 overexpression plays a crucial role in 2-CE induced oxidative damage of rat astrocytes, and that CYP2E1 expression is upregulated partially through the activation of the ERK1/2 and SP1 signaling pathways by ROS generated during CYP2E1-mediated 2-CE metabolism. This study provides novel information that can be used in elucidating the mechanism by which 1,2-DCE induces brain edema.