Transmembrane protein 72 (TMEM72) is involved in normal kidney development and tumorigenesis in renal cell carcinoma. However, the function of TMEM72 has not been experimentally examined; therefore, the role of TMEM72 is incompletely understood. In this study, we initially demonstrated that TMEM72 has four transmembrane domains (TMDs) and a long C-terminal tail.
View Article and Find Full Text PDFBackground: Propolis is a natural product collected by worker bees from a variety of plant species. As a type of propolis, Brazilian green propolis contains a large amount of artepillin C. Artepillin C is a cinnamic acid derivative and has been shown to have a wide variety of biological functions, including anti-inflammatory, antiviral and antitumor activities, in both cell culture and animal models.
View Article and Find Full Text PDFThe recognition of nonself dsRNA by retinoic acid-inducible gene-I (RIG-I) leads to the engagement of RIG-I-like receptor signaling. In addition, nonself dsRNA triggers a robust latent RNase (RNase L) activation and leads to the degradation of ribosomal structures and cell death. In contrast, nonself ssRNA is known to be recognized by TLR 7/8 in immune cells such as plasmacytoid dendritic cells and B cells, but little is known regarding the involvement of nonself ssRNA in antiviral signaling in nonimmune cells, including epithelial cells.
View Article and Find Full Text PDFAccumulation and oligomerization of amyloid-beta (Aβ) peptides have been known to be a potent cause of neurodegenerative diseases such as Alzheimer's disease (AD). To expand the possibilities of preventing AD, we investigated the effects of resveratrol dimers, gnetin C and ε-viniferin, on Aβ 1-42 (Aβ42) production and the reduced cell viability observed after Aβ42 treatment (monomers, 10 μM) in cultured SH-SY5Y human neuroblastoma cells. Among them, addition of gnetin C (20 μM) into the media reduced Aβ42 production most efficiently.
View Article and Find Full Text PDFPrevious postmortem studies demonstrated dysregulation of autophagy in patients with Parkinson's disease (PD). To clarify whether this alteration reflects a fundamental aspect of PD or represents the final stage of autophagy dysregulation resulting from a long neurodegenerative process, we focused on basal autophagy in peripheral blood mononuclear cells (PBMCs) of PD patients (n = 35) and controls (n = 23). The whole-transcriptome assay revealed downregulation of mRNAs for 6 core regulators of autophagy (UNC-51-like kinase [ULK] 3, autophagy-related [Atg] 2A, Atg4B, Atg5, Atg16L1, and histone deacetylase 6).
View Article and Find Full Text PDFBackground/aims: Cylindromatosis (CYLD), a deubiquitinase, negatively regulates nuclear factor-κB in various cells. However, its potential roles in glomerular inflammation remain unclear. Because the activation of the Toll-like receptor 3 (TLR3)/type I interferon (IFN) pathways plays a pivotal role in chronic kidney diseases (CKD), we examined the role of CYLD in the TLR3 signaling in cultured human mesangial cells (MCs).
View Article and Find Full Text PDFBiliary atresia (BA) is a disease of the newborn that is characterized by progressive, inflammatory and sclerosing cholangiopathy. Innate immune responses to viral components are thought to be involved in the pathogenesis of BA. It is also reported that some chemokines, such as CCL5, are possibly involved in the pathogenesis of experimental animal model of BA.
View Article and Find Full Text PDFAmyloid-beta (Aβ) peptides, Aβ 1-42 (Aβ42) and Aβ43, in particular, have been implicated in the pathophysiology of neurodegenerative disease such as Alzheimer's disease (AD). Rebamipide (REB), a gastrointestinal protective drug, can cross the blood-brain barrier after oral administration; however, the effects of REB on neuronal cells have not yet been reported. In this study, we investigated the effects of REB on Aβ43-induced cytotoxicity (monomers, 10μM) in cultured SH-SY5Y human neuroblastoma cells.
View Article and Find Full Text PDFBackground: Chloroquine has been reported to protect against renal damage in lupus nephritis (LN); however, its detailed mechanism in glomerular inflammation remains unclear. Upregulation of the type-I interferon (IFN) system plays a pivotal role in LN pathogenesis, therefore, we examined whether chloroquine inhibits toll-like receptor 3 (TLR3)/IFN-β signaling in cultured normal human mesangial cells (MCs).
Methods: We examined chloroquine effect on the representative TLR3/IFN-β-signaling axis, TLR3/IFN-β/retinoic acid-inducible gene-I (RIG-I)/CCL5 in MCs treated with polyinosinic-polycytidylic acid (poly IC), a synthetic viral dsRNA analog and analyzed the expression of these molecules using reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay (ELISA).
Interferon (IFN)-stimulated genes (ISGs) exert multiple functions in immune system. IFN-induced protein 35 (IFI35) is a member of ISGs, and has been suggested to regulate innate immune reaction. However, the physiological functions and pathological roles of IFI35 in the central nervous system are not characterized well.
View Article and Find Full Text PDFNon-self RNA is recognized by retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), inducing type I interferons (IFNs). Type I IFN promotes the expression of IFN-stimulated genes (ISGs), which requires the activation of signal transducer and activator of transcription-1 (STAT1). We previously reported that dsRNA induced STAT1 phosphorylation via a type I IFN-independent pathway in addition to the well-known type I IFN-dependent pathway.
View Article and Find Full Text PDFBackground/aims: Activation of Toll-like receptor 3 (TLR3) signaling followed by type I interferon (IFN) expression is crucial in antiviral and "pseudoviral" immune reactions in renal mesangial cells (MCs). These reactions are probably involved in the pathogenesis of chronic kidney disease (CKD). However, the role of IFN-induced 35-kDa protein 35 (IFI35), a type I IFN-dependent transcript, in glomerular inflammation is unclear.
View Article and Find Full Text PDFThe cytoplasmic viral sensor retinoic acid-inducible gene-I (RIG-I), which is also known as an IFN-stimulated gene (ISG), senses viral RNA to activate antiviral signaling. It is therefore thought that RIG-I is regulated in a STAT1-dependent manner. Although RIG-I-mediated antiviral signaling is indispensable for the induction of an appropriate adaptive immune response, the mechanism underlying the regulation of RIG-I expression remains elusive.
View Article and Find Full Text PDFGenetic variation is associated with diseases. As a type of genetic variation occurring with certain regularity and frequency, the single nucleotide polymorphism (SNP) is attracting more and more attention because of its great value for research and real-life application. Mitochondrial antiviral signalling protein (MAVS) acts as a common adaptor molecule for retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), which can recognize foreign RNA, including viral RNA, leading to the induction of type I interferons (IFNs).
View Article and Find Full Text PDFUpon viral infection, the cytoplasmic viral sensor retinoic acid-inducible gene-I (RIG-I) recognizes viral RNA to activate antiviral signaling to induce type I interferon (IFN). RIG-I-like receptors (RLRs) activate antiviral signaling in a tissue-specific manner. The molecular mechanism underlying antiviral signaling in the respiratory system remains unclear.
View Article and Find Full Text PDFTreatment of cells with interferons (IFNs) induces the phosphorylation of signal transducer and activator of transcription 1 (STAT1), leading to the expression of hundreds of IFN-stimulated genes (ISGs). ISGs exert various antiviral and pro-inflammatory reactions. We have previously reported that ISG56 and ISG54 are induced by polyinosinic-polycytidylic acid (poly IC), an authentic agonist for Toll-like receptor 3 (TLR3), in U373MG human astrocytoma cells.
View Article and Find Full Text PDFAlthough iron is essential in physiological processes, accumulation of iron in central nervous system is associated with various neurological diseases including Alzheimer's disease and Parkinson's disease. Innate immune reactions are involved in the pathogenesis of those diseases, but roles of iron in innate immunity are not known well. In the present study, pretreatment of U373MG human astrocytoma cells with an iron chelator desferrioxamine (DFX) inhibited the expression of CXCL10 induced by a Toll-like receptor 3 (TLR3) agonist polyinosinic-polycytidylic acid (poly IC).
View Article and Find Full Text PDFAmyloid-beta (Aβ) peptides, Aβ 1-42 (Aβ42) and Aβ43 in particular, cause neurotoxicity and cell death in the brain of Alzheimer's disease (AD) at higher concentrations. Carnosic acid (CA), a phenolic diterpene compound in the labiate herbs rosemary and sage, serves as an activator for neuroprotective and neurotrophic functions in brain cells. We investigated the effect of CA on apoptosis induced by Aβ42 or Aβ43 in cultured SH-SY5Y human neuroblastoma cells.
View Article and Find Full Text PDFToll-like receptor (TLR) 3 is a pattern recognition receptor that recognizes double-stranded RNA (dsRNA). TLR3 signaling in astrocytes leads to the expression of interferon-β (IFN-β), and IFN-β regulates immune and inflammatory reactions by inducing IFN-stimulated genes (ISGs). We demonstrated in the present study that polyinosinic-polycytidylic acid (poly IC), an authentic dsRNA, up-regulated the expression of ISG54 and ISG56 in U373MG human astrocytoma cells.
View Article and Find Full Text PDFAim: It has been reported that tumor necrosis factor (TNF)-α plays dual controversial roles, beneficial or detrimental, in the pathogenesis of murine lupus nephritis (LN). However, its precise role in the development of human LN remains to be determined.
Methods: We examine the effect of pretreatment with TNF-α on the toll-like receptor 3 (TLR3) signaling induced by polyinosinic-polycytidylic acid (poly IC), a synthetic analog of viral dsRNA that makes "pseudoviral" infection in cultured normal human mesangial cells, and analyzed the expression of CC chemokine ligand 5 (CCL5) via TLR3/interferon (IFN)-β/retinoic acid-inducible gene-I (RIG-I) pathway by reverse transcriptase-polymerase chain reaction, Western blotting and enzyme-linked immunosorbent assay.
Melanoma differentiation-associated gene 5 (MDA-5) and retinoic acid-inducible gene-I (RIG-I)are members of DExH family of proteins, and known to play important roles in antiviral responses to induce type I interferons (IFNs). MDA-5 has been thought to sense RNA virus with long(>1 kb) double-stranded RNA. However, MDA-5 is also induced by type II IFN that is involved in acquired immunity, suggesting that role of MDA-5 remains to be elucidated.
View Article and Find Full Text PDFAmyloid beta (Aβ) peptides are key molecules in the pathogenesis of Alzheimer's disease (AD). The sequential cleavage of amyloid precursor protein (APP) by the β- and γ-secretases generates Aβ peptides; however, the alternate cleavage of APP by the α- and γ-secretases decreases Aβ production. We previously reported that carnosic acid (CA), a phenolic diterpene compound found in the labiate herbs rosemary and sage, suppresses Aβ (1-40 and 1-42) production by activating α-secretase in cultured SH-SY5Y human neuroblastoma cells (Neurosci.
View Article and Find Full Text PDFIFN-ε is a unique type I IFN whose constitutive expression in lung, brain, small intestine, and reproductive tissues is only partially understood. Our previous observation that posttranscriptional events participate in the regulation of IFN-ε mRNA expression led us to investigate whether the 5' and/or 3' untranslated regions (UTR) have regulatory functions. Surprisingly, we found that full-length IFN-ε 5'UTR markedly suppressed mRNA expression under basal conditions.
View Article and Find Full Text PDFToll-like receptor (TLR) 4 is a pattern recognition receptor, and recognizes not only bacterial lipopolysaccharide (LPS) but also endogenous danger-associated molecular patterns released from dying or injured cells. It has been reported that TLR4 signaling in astrocytes plays an important role in various neurological diseases. However, details of TLR4 signaling in astrocytes are not fully elucidated.
View Article and Find Full Text PDFBackground: It is known that recognition of bacterial lipopolysaccharide (LPS) and various endogenous ligands by Toll-like receptor 4 (TLR4) induces inflammatory reactions. However, the role of TLR4 activation in mesangial inflammation remains to be elucidated. Retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5) are putative RNA helicases and are involved in immune and inflammatory reactions.
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