RESUMO
Inflammation is provoked by host immune reactions to pathogenic or tissue injury and is arbitrated by cytokines. Among the pro-inflammatory cytokines, the tumor necrosis factor α (TNF-α) and interleukin 1ß (IL-1ß) are main mediators of inflammation. The production of these pro-inflammatory cytokines is mainly triggered in macrophages by harmful stimuli including microbial pathogens, irritants, and toxic cellular components, and plays key roles in the palpation of the inflammatory response. Among the therapeutic antibodies for the treatment of inflammation, those targeting TNF-α (including adalimumab and infliximab) are frequently used in clinical settings. Although IL-1ß is a key cytokine for the onset of inflammatory diseases, such as inflammatory bowel disease (IBD) and type 2 diabetes (T2DM), few therapeutic antibodies exist for this cytokine, with the exception of canakinumab. Canakinumab binds to human IL-1ß, but does not bind to murine IL-1ß, which hampers its experimental use. Therefore, inflammation-therapeutic antibodies that bind to IL-1ß of various mammals are needed. In this study, we report the development of an antibody that bound to IL-1ß of various mammalian species and exhibited therapeutic effects in inflammatory diseases.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Colite/tratamento farmacológico , Inflamação/tratamento farmacológico , Interleucina-1beta/antagonistas & inibidores , Animais , Anticorpos Monoclonais/imunologia , Linhagem Celular , Colite/imunologia , Colite/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Humanos , Inflamação/imunologia , Inflamação/patologia , Interleucina-1beta/imunologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , RatosRESUMO
Intestinal epithelial cells form a barrier between the intestinal lumen and host connective tissues and play an important role in maintaining intestinal nutrient homeostasis. This study investigated effects of Allomyrina dichotoma (rhinoceros beetle) larval extract (ADLE) on the intestinal barrier damage and explored mechanisms for reversing intestinal barrier dysfunction in lipopolysaccharide (LPS)-stimulated Caco-2, human intestinal epithelial cells. LPS reduced intestinal epithelial barrier function by increasing transepithelial electrical resistance, and this effect was significantly attenuated by ADLE treatment. ADLE also significantly countered the inhibition of tight junction-related protein expression in both LPS-induced Caco-2 cells and intestine from HFD-induced mice. Moreover, ADLE significantly decreased expression and production of inflammatory factors, such as iNOS, cox-2, nitric oxide, and cytokines induced by LPS stimulus. Reduction in phosphorylation of adenosine monophosphate-activated protein kinase was averted by ADLE treatment in LPS treated INS-1 cells. Finally, reactive oxygen stress level was decreased and ATP production was increased by ADLE treatment. ADLE appears to display gut health-promoting effects by reducing inflammation and inducing tight junction proteins in Caco-2 cells. Therefore, ADLE might be useful for preventing or treating intestine cell damage in inflammatory bowel disease.
Assuntos
Besouros/química , Insetos Comestíveis/química , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Proteínas de Junções Íntimas/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Células CACO-2 , Dieta Hiperlipídica/efeitos adversos , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/prevenção & controle , Mucosa Intestinal/patologia , Larva/química , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Permeabilidade/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
The immunoglobulin G (IgG) molecule has a long circulating serum half-life (~3 weeks) through pH- dependent FcRn binding-mediated recycling. To hijack the intracellular trafficking and recycling mechanism of IgG as a way to extend serum persistence of non-antibody therapeutic proteins, we have evolved the ectodomain of a low-affinity human FcγRIIa for enhanced binding to the lower hinge and upper CH2 region of IgG, which is very far from the FcRn binding site (CH2-CH3 interface). High-throughput library screening enabled isolation of an FcγRIIa variant (2A45.1) with 32-fold increased binding affinity to human IgG1 Fc (equilibrium dissociation constant: 9.04 × 10-7 M for wild type FcγRIIa and 2.82 × 10-8 M for 2A45.1) and significantly improved affinity to mouse serum IgG compared to wild type human FcγRIIa. The in vivo pharmacokinetic profile of PD-L1 fused with engineered FcγRIIa (PD-L1-2A45.1) was compared with that of PD-L1 fused with wild type FcγRIIa (PD-L1-wild type FcγRIIa) and human PD-L1 in mice. PD-L1-2A45.1 showed 11.7- and 9.7-fold prolonged circulating half-life (t1/2 ) compared to PD-L1 when administered intravenously and intraperitoneally, respectively. In addition, the AUCinf of PD-L1-2A45.1 was two-fold higher compared to that of PD-L1-wild type FcγRIIa. These results demonstrate that engineered FcγRIIa fusion offers a novel and successful strategy for prolonging serum half-life of therapeutic proteins.
Assuntos
Engenharia de Proteínas/métodos , Receptores de IgG , Proteínas Recombinantes de Fusão , Animais , Evolução Molecular Direcionada , Biblioteca Gênica , Meia-Vida , Humanos , Imunoglobulina G , Camundongos , Mutação/genética , Ligação Proteica , Receptores de IgG/química , Receptores de IgG/genética , Receptores de IgG/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismoRESUMO
Dysregulation of immune responses to environmental antigens by the intestine leads to the chronic inflammatory disease, inflammatory bowel disease (IBD). Recent studies have thus sought to identify a dietary component that can inhibit lipopolysaccharide (LPS)-induced nuclear factor-kappa beta (NF-κB) signaling to ameliorate IBD. This study assessed if the lactic acid bacteria (LAB) from kimchi, suppresses the expression of tumor necrosis factor-alpha (TNF-α) in peritoneal macrophages induced by LPS. Leuconostoc lactis EJ-1, an isolate from LAB, reduced the expression of interleukin-6 (IL-6) and IL-1ß in peritoneal macrophages induced by LPS. The study further tested whether EJ-1 alleviates colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS) in mice. TNBS significantly increased myeloperoxidase (MPO) expression, macroscopic colitis scores, and colon shortening. Oral administration of L. lactis EJ-1 resulted in an inhibited in TNBS-induced loss in body weight, colon shortening, MPO activity, and NF-κB and inducible nitric oxide synthase expression; it also led to a marked reduction in cyclooxygenase-2 expression. L. lactis EJ-1 also inhibited the TNBS-induced expression of TNF-α, IL-1ß, and IL-6; however, it induced the expression of IL-10. The M2 macrophage markers arginase I, IL-10, and CD206 were elevated by EJ-1. Collectively, these results suggest that EJ-1 inhibits the NF-κB signaling and polarizes M1- to M2-macrophage transition, which help in ameliorating colitis.
Assuntos
Colite/terapia , Leuconostoc , Lipopolissacarídeos/imunologia , Macrófagos Peritoneais/metabolismo , Plantas Comestíveis/microbiologia , Animais , Colite/induzido quimicamente , Colo/metabolismo , Modelos Animais de Doenças , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/terapia , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Leuconostoc/imunologia , Leuconostoc/metabolismo , Lipopolissacarídeos/metabolismo , Camundongos , NF-kappa B/metabolismo , Transdução de Sinais/imunologia , Ácido Trinitrobenzenossulfônico/efeitos adversosRESUMO
The accumulation of soluble amyloid-ß (Aß) peptides produces profound neuronal changes in the brain during the pathogenesis of Alzheimer's disease. Excessive levels of Aß disrupt excitatory synaptic transmission by promoting the removal of synaptic AMPA receptors (AMPARs), dendritic spine loss, and synaptic depression. Recently, activity-dependent ubiquitination of the GluA1 subunit has been shown to regulate the intracellular sorting of AMPARs toward late endosomes for degradation. However, whether this ubiquitin signaling pathway mediates Aß-induced loss of surface AMPARs is unknown. In this study, we demonstrate that acute exposure of cultured neurons to soluble Aß oligomers induces AMPAR ubiquitination concomitant with the removal of AMPARs from the plasma membrane. Importantly, expression of the GluA1 ubiquitin-deficient mutants inhibited the adverse effects of Aß on the surface expression of AMPARs in neurons. Furthermore, we revealed the cross-talk between GluA1 ubiquitination and phosphorylation, in particular phosphorylation at Ser-845, which is crucial for AMPAR recycling and is known to be dephosphorylated in the presence of Aß. Our data showed that the GluA1 ubiquitin-deficient mutant enhances GluA1 phosphorylation on Ser-845. Conversely, the GluA1 S845D phosphomimetic mutant reduced binding with Nedd4-1 and hence the ubiquitination of AMPARs. Importantly, the GluA1 S845D mutant also prevented Aß-induced removal of surface AMPARs. Taken together, these findings provide the first demonstration of the dynamic cross-modulation of GluA1 ubiquitination and phosphorylation, a process that is perturbed by Aß, in regulating the membrane sorting decision that ultimately determines the number of AMPARs on the cell surface.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Mutação de Sentido Incorreto , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Receptores de AMPA/metabolismo , Ubiquitinação , Substituição de Aminoácidos , Peptídeos beta-Amiloides/genética , Animais , Células Cultivadas , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Ubiquitina-Proteína Ligases Nedd4 , Fragmentos de Peptídeos/genética , Fosforilação , Ratos , Receptores de AMPA/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
To understand the anti-colitic effects of probiotics that up-regulate interleukin (IL)-10 expression in dendritic cells (DCs) and macrophages, we isolated Lactobacillus sakei K17, which potently induced IL-10 expression in DCs and peritoneal macrophages in vitro, among the lactic acid bacteria strains collected from kimchi and investigated its anti-inflammatory effect in mice with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis. Oral administration of K17 (2 × 109 CFU·mouse-1·day-1) in mice with TNBS-induced colitis suppressed colon shortening and myeloperoxidase activity, as well as infiltration of CD86+ cells into the colon. Treatment with K17 also increased TNBS-suppressed expression of tight junction proteins and IL-10, but inhibited activation of nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases and expression of tumor necrosis factor α and IL-17. Its effect was comparable with that of sulfasalazine (50 mg/kg), a positive commercial ant-colitic drug. Furthermore, treatment with K17 (1 × 105 CFU/mL) potently inhibited lipopolysaccharide (LPS)-stimulated NF-κB activation in DCs and peritoneal macrophages and restored tight junction protein expression in LPS-stimulated Caco-2 cells. These findings suggest that Lactobacillus sakei K17 may ameliorate colitis by up-regulating the expression of IL-10 and tight junction proteins and inhibiting NF-κB activation.
RESUMO
BACKGROUND AND AIM: The anti-inflammatory effects of liquiritigenin, a major flavonoid isolated from Glycyrrhizae uralensis, have been reported in many inflammation models. However, its protective effects have not been reported in a colitis model. This study investigated the anti-inflammatory effect and mechanism of liquiritigenin for trinitrobenzene sulfonic acid (TNBS)-induced colitis in mice. METHODS: Male mice imprinting control regions (ICR) were randomly divided into five groups: normal, TNBS-induced colitis, colitis treated with liquiritigenin at low dose (10 mg/kg) and high dose (20 mg/kg), or mesalazine (10 mg/kg). TNBS colitis induction was performed except for in the normal group, and they were treated with liquiritigenin or mesalazine except control group. The treatment effect was measured after three days treatment, by body weight, colon length, macroscopic score, histological score, levels of cytokines (tumor necrosis factor-α, interleukin [IL]-1ß, IL-6, and IL-10) in colon tissue as well as the nuclear factor kappa-light-chain-enhancer pathway of activated B cells (NF-κB) activation. RESULTS: Mice treated with high-dose liquiritigenin showed significant body weight gain, inhibition of colon shortening, protective effect on histological damages, and myeloperoxidase activity of colon tissue compared with the control group. Furthermore, mice treated with high-dose liquiritigenin experienced significantly suppressed tumor necrosis factor-α, IL-1ß, and IL-6 as well as enhanced IL-10 expression (all P < 0.05). High-dose liquiritigenin treatment group showed significant decreases in TNBS-induced phosphorylation of IKKß, p65, and IκB-α. CONCLUSION: Liquiritigenin may ameliorate TNBS-induced colitis in mice by suppressing expression of pro-inflammatory cytokines through NF-κB pathway.
Assuntos
Anti-Inflamatórios , Colite/induzido quimicamente , Colite/tratamento farmacológico , Flavanonas/administração & dosagem , Flavanonas/farmacologia , Ácido Trinitrobenzenossulfônico , Animais , Colite/prevenção & controle , Colo/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Mediadores da Inflamação/metabolismo , Masculino , Mesalamina/administração & dosagem , Camundongos Endogâmicos ICR , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Aging is associated with Alzheimer's disease (AD), cardiovascular disease and cancer. Oxidative stress is considered as a major factor that accelerates the aging process. To understand the ability of lactic acid bacteria to ameliorate memory impairment caused by aging, we investigated the effect of Lactobacillus pentosus var. plantarum (C29), which is known to protect against scopolamine-induced memory impairment, on oxidative stress (D-galactose)-induced memory impairment in mice. D-Galactose was subcutaneously injected to 20-week old male C57BL/6J mice for 10 weeks, with oral administration of C29 for the final 5 weeks. Excessive intake of D-galactose not only impaired memory, which was indicated by passive avoidance, Y-maze, and Morris water-maze tasks, but also reduced the expression of brain-derived neurotrophic factor (BDNF) and hippocampal doublecortin (DCX) and the activation of cAMP response element-binding protein (CREB). C29 treatment ameliorated D-galactose-induced memory impairment and reversed the suppression of BDNF and DCX expression and CREB activation. Moreover, C29 decreased the expression of a senescence marker p16 and inflammation markers p-p65, p-FOXO3a, cyclooxygenase (COX)-2, and inducible NO synthase (iNOS). C29 treatment inhibited D-galactose-induced expression of M1 polarization markers tumor necrosis factor-α and arginase II, and attenuated the d-galactose-suppressed expression of M2 markers IL-10, arginase I and CD206. Taken together, these findings suggest that C29 may ameliorate memory impairment and M1 macrophage-polarized inflammation caused by aging.
Assuntos
Envelhecimento/fisiologia , Galactose/toxicidade , Inflamação/terapia , Lactobacillus/crescimento & desenvolvimento , Transtornos da Memória/terapia , Estresse Oxidativo , Probióticos/administração & dosagem , Animais , Biomarcadores/análise , Proteína Duplacortina , Masculino , Camundongos Endogâmicos C57BL , Modelos AnimaisRESUMO
Pyrolysis has been proposed to stabilize heavy metals present in livestock manure. However, many studies have not considered the applicability of manure-derived biochar containing endogenous heavy metals as an agricultural fertilizer. This study investigated the mechanisms through which pyrolysis stabilizes endogenous heavy metals in swine manure and the long-term stability of endogenous heavy metals in the biochar. As pyrolysis temperature increased from 300 °C to 700 °C, the potential ecological risk index decreased from 46.3 to 4.8 because the unstable fraction converted to organic-sulfide bonds and residues. Biochar prepared at 600 °C was the most stable and met the World Health Organization's phyto-availability standards (Cu 10 mg/kg, Zn 0.6 mg/kg). Fourier transform infrared spectroscopy and X-ray diffraction analyses indicated that endogenous heavy metals were stabilized by complexation with organic matter and precipitated as metal-phosphate forms. After 40 cycles of wet-dry aging, the leachability of heavy metals (Cu 6.0 mg/kg, Zn 460.6 mg/kg) from biochar was still lower than that of swine manure (Cu 102.5 mg/kg and Zn 704.9 mg/kg), indicating the long-term stability of the heavy metals in the biochar. Pyrolysis dramatically lowered the environmental threat posed by endogenous heavy metals, demonstrating the applicability of swine manure-derived biochar compared to manure.
Assuntos
Carvão Vegetal , Esterco , Metais Pesados , Esterco/análise , Carvão Vegetal/química , Metais Pesados/análise , Animais , Pirólise , Suínos , Fertilizantes/análiseRESUMO
Lactic acid bacteria (LAB) have recently attracted considerable attention as treatment options for immune diseases, the incidence of which has been increasing worldwide. The ability of tumor necrosis factor-α producing LAB isolated from cheese to inhibit NF-κB activation in lipopolysaccharide (LPS)-stimulated peritoneal macrophages was investigated. Among the tested LAB, Lactobacillus casei HY7213 inhibited NF-κB activation most potently. Therefore, we measured its immunopotentiating effect in cyclophosphamide (CP)-immunosuppressed mice. When HY7213 was orally administered for 5 or 15 d, it reversed the CP immunosuppressant effect by increasing body and spleen weights, blood red and white blood cells levels, and splenocyte and bone marrow cells counts. Treatment with CP in mice markedly reduced concanavalin A (ConA)-induced T cell proliferation to 54% compared to the normal group. Oral administration of HY7213 in CP-immunosuppressed mice reversed that value to 95% of the normal group on day 15. Furthermore, oral administration of HY7213 to CP-treated mice significantly enhanced the expression of IL-2 and IFN-γ in ConA-induced splenic cytotoxic T cells, restored the CP-impaired phagocytosis of macrophage, and increased the cytotoxicity of natural killer (NK) and cytotoxic T cells derived from spleen and bone marrow against YAC-1. Based on these findings, we suggest that HY7213 may promote the recovery of immunosuppression caused by chemotherapeutic agents, such as CP, by activating NK cells, cytotoxic T cells and macrophages.
Assuntos
Antineoplásicos Alquilantes/efeitos adversos , Ciclofosfamida/efeitos adversos , Tolerância Imunológica/efeitos dos fármacos , Células Matadoras Naturais/efeitos dos fármacos , Lacticaseibacillus casei/imunologia , Macrófagos Peritoneais/efeitos dos fármacos , Linfócitos T Citotóxicos/efeitos dos fármacos , Animais , Técnicas de Cultura de Células , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática , Tolerância Imunológica/imunologia , Células Matadoras Naturais/imunologia , Macrófagos Peritoneais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Linfócitos T Citotóxicos/imunologiaRESUMO
In the mammalian brain, neurogenesis is maintained throughout adulthood primarily in two typical niches, the subgranular zone (SGZ) of the dentate gyrus and the subventricular zone (SVZ) of the lateral ventricles and in other nonclassic neurogenic areas (e.g., the amygdala and striatum). During prenatal and early postnatal development, neural stem cells (NSCs) differentiate into neurons and migrate to appropriate areas such as the olfactory bulb where they integrate into existing neural networks; these phenomena constitute the multistep process of neurogenesis. Alterations in any of these processes impair neurogenesis and may even lead to brain dysfunction, including cognitive impairment and neurodegeneration. Here, we first summarize the main properties of mammalian neurogenic niches to describe the cellular and molecular mechanisms of neurogenesis. Accumulating evidence indicates that neurogenesis plays an integral role in neuronal plasticity in the brain and cognition in the postnatal period. Given that neurogenesis can be highly modulated by a number of extrinsic and intrinsic factors, we discuss the impact of extrinsic (e.g., alcohol) and intrinsic (e.g., hormones) modulators on neurogenesis. Additionally, we provide an overview of the contribution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to persistent neurological sequelae such as neurodegeneration, neurogenic defects and accelerated neuronal cell death. Together, our review provides a link between extrinsic/intrinsic factors and neurogenesis and explains the possible mechanisms of abnormal neurogenesis underlying neurological disorders.
Assuntos
COVID-19 , Células-Tronco Neurais , Animais , Humanos , Adulto , SARS-CoV-2 , Neurogênese/fisiologia , Neurônios , MamíferosRESUMO
Artemisia princeps (family Asteraceae) is a natural product broadly used as an antioxidative, hepatoprotective, antibacterial, and anti-inflammatory agent in East Asia. In the present study, eupatilin, the main constituent of Artemisia princeps, was investigated as an antihyperlipidemic agent. Eupatilin inhibited 3-hydroxy-3-methylglutaryl (HMG)-CoA reductase (HCR), an enzyme that is a therapeutic target for hyperlipidemia, in an ex vivo assay using rat liver. In addition, oral administration of eupatilin significantly lowered the serum levels of total cholesterol (TC) and triglycerides (TG) in corn oil-induced and Triton WR-1339-induced hyperlipidemic mice. These results suggest that eupatilin can alleviate hyperlipidemia by inhibiting HCR.
RESUMO
Inflammatory bowel disease (IBD), a chronic inflammatory disease, results from dysregulation of the immune responses. Some lactic acid bacteria (LAB), including Lactobacillus, alleviate IBD through immunomodulation. In this study, the anti-colitis effect of LAB isolated from human breast milk was investigated in a mouse model induced acute colitis with 2,4,6-trinitrobenzene sulfonic acid (TNBS). TNBS remarkably increased weight loss, colon shortening, and colonic mucosal proliferation, as well as the expression levels of inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-1ß. Oral administration of LAB isolated from human breast milk resulted in a reduction in TNBS-induced colon shortening, as well as induced cyclooxygenase (COX)-2, nitric oxide synthase (iNOS), nuclear factor-kappa B (NF-κB). In addition, LAB suppressed inflammatory cytokines such as TNF-α, IL-6, and IL-1ß, and thus showed an effect of suppressing the level of inflammation induced by TNBS. Furthermore, LAB alleviated gut microbiota dysbiosis, and inhibited intestinal permeability by increasing the expression of intestinal tight junction protein including ZO-1. Collectively, these results suggest that LAB isolated from human breast milk can be used as a functional food for colitis treatment by regulating NF-κB signaling, gut microbiota and increasing expression of intestinal tight junction protein.
Assuntos
Colite , Doenças Inflamatórias Intestinais , Lactobacillales , Feminino , Humanos , Camundongos , Animais , NF-kappa B/metabolismo , Ácido Trinitrobenzenossulfônico , Fator de Necrose Tumoral alfa/metabolismo , Lactobacillales/metabolismo , Leite Humano , Colite/induzido quimicamente , Colite/patologia , Colo/patologia , Citocinas/metabolismo , Ciclo-Oxigenase 2/metabolismo , Proteínas de Junções Íntimas/metabolismoRESUMO
The recruitment of synaptic α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors underlies the strengthening of neuronal connectivity during learning and memory. This process is triggered by N-methyl-D-aspartate (NMDA) receptor-dependent postsynaptic Ca2+ influx. Synaptotagmin (Syt)-1 and -7 have been proposed as Ca2+ sensors for AMPA receptor exocytosis but are functionally redundant. Here, we identify a cytosolic C2 domain-containing Ca2+-binding protein, Copine-6, that forms a complex with AMPA receptors. Loss of Copine-6 expression impairs activity-induced exocytosis of AMPA receptors in primary neurons, which is rescued by wild-type Copine-6 but not Ca2+-binding mutants. In contrast, Copine-6 loss of function does not affect steady-state expression or tetrodotoxin-induced synaptic upscaling of surface AMPA receptors. Loss of Syt-1/Syt-7 significantly reduces Copine-6 protein expression. Interestingly, overexpression of wild-type Copine-6, but not the Ca2+-binding mutants, restores activity-dependent exocytosis of AMPA receptors in Syt-1/Syt-7 double-knockdown neurons. We conclude that Copine-6 is a postsynaptic Ca2+ sensor that mediates AMPA receptor exocytosis during synaptic potentiation.
Assuntos
Exocitose , Receptores de AMPA , Receptores de AMPA/metabolismo , Exocitose/fisiologia , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Cálcio/metabolismoRESUMO
Gain-of-function mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are common in familial forms of Parkinson's disease (PD), which is characterized by progressive neurodegeneration that impairs motor and cognitive function. We previously demonstrated that LRRK2-mediated phosphorylation of ß-amyloid precursor protein (APP) triggers the production and nuclear translocation of the APP intracellular domain (AICD). Here, we connected LRRK2 to AICD in a feed-forward cycle that enhanced LRRK2-mediated neurotoxicity. In cooperation with the transcription factor FOXO3a, AICD promoted LRRK2 expression, thus increasing the abundance of LRRK2 that promotes AICD activation. APP deficiency in LRRK2G2019S mice suppressed LRRK2 expression, LRRK2-mediated mitochondrial dysfunction, α-synuclein accumulation, and tyrosine hydroxylase (TH) loss in the brain, phenotypes associated with toxicity and loss of dopaminergic neurons in PD. Conversely, AICD overexpression increased LRRK2 expression and LRRK2-mediated neurotoxicity in LRRK2G2019S mice. In LRRK2G2019S mice or cultured dopaminergic neurons from LRRK2G2019S patients, treatment with itanapraced reduced LRRK2 expression and was neuroprotective. Itanapraced showed similar effects in a neurotoxin-induced PD mouse model, suggesting that inhibiting the AICD may also have therapeutic benefits in idiopathic PD. Our findings reveal a therapeutically targetable, feed-forward mechanism through which AICD promotes LRRK2-mediated neurotoxicity in PD.
Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Doença de Parkinson , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Neurônios Dopaminérgicos/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Camundongos , Mutação , Doença de Parkinson/genética , Doença de Parkinson/metabolismoRESUMO
To isolate antipruritic lactic acid bacteria (LAB) from kimchi, a traditional Korean food, we investigated the interleukin (IL)-4 production-inhibitory effect in the colon of mice for previously isolated LAB. Orally administered Lactobacillus plantarum PM008 potently inhibited the expression of IgE-switching cytokine, IL-4, and of proinflammatory cytokines, IL-1ß and TNF-α, in the colon of mice. Its inhibitory effect was dependent on the dosage and administration period. When PM008 was orally administered to mice, the number of PM008 detected in the intestine and feces by polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH) methods was dependent on the administration dosage and period. The number of PM008 attached in the intestine was gradually decreased with increasing time after completion of its oral administration. PM008 dose-dependently inhibited the scratching behavior induced by histamine or compound 48/80. PM008 treated at a dose of 1 × 10(10) CFU for 14 days inhibited the histamine- and compound 48/80-induced scratching behaviors by 32.8% and 48.6%, respectively. This inhibitory effect continued, although reduced, at 7 days after stopping the oral administration of PM008 attached in the intestine. Based on these findings, L. plantarum PM008 may improve pruritus by inhibiting IL-4 expression.
Assuntos
Antipruriginosos/farmacologia , Lactobacillus plantarum , Probióticos/farmacologia , Prurido/tratamento farmacológico , Animais , Colo/imunologia , Colo/metabolismo , Colo/microbiologia , Fezes/microbiologia , Histamina/farmacologia , Interleucina-1beta/antagonistas & inibidores , Interleucina-4/antagonistas & inibidores , Interleucina-4/biossíntese , Lactobacillus plantarum/isolamento & purificação , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Probióticos/isolamento & purificação , Prurido/induzido quimicamente , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese , p-Metoxi-N-metilfenetilamina/farmacologiaRESUMO
Increased tight junction permeability and overproduction of proinflammatory cytokines are crucial pathophysiological mechanisms in inflammatory bowel disease (IBD). This study evaluated anti-inflammatory effects of aqueous ethanolic Gryllus bimaculatus extract (AE-GBE) against intestinal permeability on lipopolysaccharide (LPS)-treated Caco-2 cells. Treatment with AE-GBE increased cell viability and significantly reduced inflammatory mediators such as nitric oxide and LPS-induced reactive oxidative stress. LPS increased the expression levels of iNOS, Cox-2, and 4-hydroxylnonenal; however, these levels were attenuated by AE-GBE treatment. Moreover, the mRNA and protein expression levels of the inflammatory cytokines TNFα, IL-6, IL-1ß, and IFNγ were increased by LPS, but were significantly reduced by AE-GBE treatment. Intestinal epithelial permeability and the related expression of the proteins Zoula ocludence-1, occludin, and claudin-1 was increased by LPS treatment, and this effect was significantly reduced by AE-GBE treatment. The reduction in AMPK phosphorylation in LPS-treated Caco-2 cells was reversed in activation by co-treatment with AE-GBE. In conclusion, AE-GBE can protect epithelial cells from LPS-induced impaired barrier integrity by increasing tight junction proteins and preventing various inflammatory mediators. Thus, AE-GBE has the potential to improve inflammation-related diseases, including IBD, by inhibiting excessive production of inflammation-inducing mediators.
RESUMO
Transplantation of differentiated neurons derived from either human embryonic stem cells (hESCs) or induced pluripotent stem cells (iPSCs) is an emerging therapeutic strategy for various neurodegenerative diseases. One important aspect of transplantation is the accessibility to track and control the activity of the stem cells-derived neurons post-transplantation. Recently, the characteristics of organic nanoparticles (NPs) with aggregation-induced emission (AIE) have emerged as efficient cell labeling reagents, where positive outcomes were observed in long-term cancer cell tracing in vivo. In the current study, we designed, synthesized, and analyzed the biocompatibility of AIE-NPs in cultured neurons such as in mouse neuronal progenitor cells (NPCs) and hESC-derived neurons. Our data demonstrated that AIE-NPs show high degree of penetration into cells and presented intracellular long-term retention in vitro without altering the neuronal proliferation, differentiation, and viability. Furthermore, we have tracked AIE-NPs labeled neuronal grafts in mouse brain striatum in various time points post-transplantation. We demonstrated prolonged cellular retention of AIE-NPs labeled neuronal grafts 1 month post-transplantation in mouse brain striatum. Lastly, we have shown activation of brain microglia in response to AIE-NPs labeled grafts. Together, these findings highlight the potential application of AIE-NPs in neuronal transplantation.
Assuntos
Células-Tronco Embrionárias Humanas , Células-Tronco Pluripotentes Induzidas , Nanopartículas , Diferenciação Celular , Neurônios , Transplante de Células-TroncoRESUMO
BACKGROUD/OBJECTIVES: Allomyrina dichotoma larva (ADL), one of the many edible insects recognized as future food resources, has a range of pharmacological activities. In a previous study, an ADL extract (ADLE) reduced the hepatic insulin resistance of high-fat diet (HFD)-induced diabetic mice. On the other hand, the associated molecular mechanisms underlying pancreatic beta-cell dysfunction remain unclear. This study examined the effects of ADLE on palmitate-induced lipotoxicity in a beta cell line of a rat origin, INS-1 cells. MATERIALS/METHODS: ADLE was administered to high-fat diet treated mice. The expression of apoptosis-related molecules was measured by Western blotting, and reactive oxidative stress generation and nitric oxide production were measured by DCH-DA fluorescence and a Griess assay, respectively. RESULTS: The administration of ADLE to HFD-induced diabetic mice reduced the hyperplasia, 4-hydroxynonenal levels, and the number of apoptotic cells while improving the insulin levels compared to the HFD group. Treatment of INS-1 cells with palmitate reduced insulin secretion, which was attenuated by the ADLE treatment. Furthermore, the ADLE treatment prevented palmitate-induced cell death in INS-1 cells and isolated islets by reducing the apoptotic signaling molecules, including cleaved caspase-3 and PARP, and the Bax/Bcl2 ratio. ADLE also reduced the levels of reactive oxygen species generation, lipid accumulation, and nitrite production in palmitate-treated INS-1 cells while increasing the ATP levels. This effect corresponded to the decreased expression of inducible nitric oxide synthase (iNOS) mRNA and protein. CONCLUSIONS: ADLE helps prevent lipotoxic beta-cell death in INS-1 cells and HFD-diabetic mice, suggesting that ADLE can be used to prevent or treat beta-cell damage in glucose intolerance during the development of diabetes.
RESUMO
Lactobacillus sakei S1 strongly inhibits the expression of interleukin (IL)-6 and IL-1ß in lipopolysaccharide-induced peritoneal macrophages by a mechanism for which lactic acid bacteria from kimchi that inhibit tumor necrosis factor-alpha (TNF-κ) were isolated. Therefore, we further evaluated the protective effect of this strain on the colitis mouse model induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). TNBS significantly elevated myeloperoxidase (MPO) expression, macroscopic scores, and colon shortening. Oral L. sakei S1 administration resulted in reduction of TNBS-induced loss in body weight, colon shortening, MPO activity, expression of cyclooxygenase (COX)-2, inducible nitric oxide synthase (iNOS) and nuclear factor-kappa B (NF-κB). L. sakei S1 inhibited the expression of inflammatory cytokines IL-1ß, IL-6 and TNF-κ, induced by TNBS, but enhanced IL-10 expression. L. sakei S1 showed resistance to artificial digestive juices and adherence to intestinal epithelial Caco-2 cells. Thus, L. sakei S1 may inhibit the NF-κB pathway and be used in functional food to treat colitis.