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DCN1, a critical co-E3 ligase during the neddylation process, is overactivated in many diseases, such as cancers, heart failure as well as fibrotic diseases, and has been regarded as a new target for drug development. Herein, we designed and synthesized a new class of 1,2,4-triazole-3-thione-based DCN1 inhibitors based the hit HD1 identified from high-throughput screening and optimized through numerous structure-activity-relationship (SAR) explorations. HD2 (IC50= 2.96 nM) was finally identified and represented a highly potent and selective DCN1 inhibitor with favorable PK properties and low toxicity. Amazingly, HD2 effectively relieved Ang II/TGFß-induced cardiac fibroblast activation in vitro, and reduced ISO-induced cardiac fibrosis as well as remodeling in vivo, which was linked to the inhibition of cullin 3 neddylation and its substrate Nrf2 accumulation. Our findings unveil a novel 1,2,4-triazole-3-thione-based derivative HD2, which can be recognized as a promising lead compound targeting DCN1 for cardiac fibrosis and remodeling.
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The interleukin-17 (IL-17) family of cytokines has emerged as a critical player in autoimmune disease, including systemic lupus erythematosus (SLE). However, the role of IL-17B, a poorly understood cytokine, in the pathogenesis of SLE is still not clear. In this study, we investigated the role of IL-17B in the activation and differentiation of B cells, and the pathogenesis of SLE. Intriguingly, IL-17B deficiency aggravated disease in lupus-prone mice and promoted the activation of B cells and the differentiation of germinal center (GC) B cells and plasma cells, while recombinant mouse IL-17B (rmIL-17B) significantly alleviated disease in lupus-prone mice. Mechanistically, rmIL-17B inhibited the activation of the Toll-like receptor (TLR) and interferon (IFN) pathways in B cells by downregulating the FASN-mediated lipid metabolism. Loss of FASN significantly alleviated the disease in lupus-prone mice and inhibited the activation and differentiation of B cells. In addition, B cells had greater FASN expression and lower IL-17RB levels in patients with SLE than in healthy controls. Our study described the role of IL-17B in regulating B-cell activation and differentiation, and alleviating the onset of SLE. These findings will lay a theoretical foundation for further understanding of the pathogenesis of SLE.
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Key gene mutations are essential for colorectal cancer (CRC) development; however, how the mutated tumor cells impact the surrounding normal cells to promote tumor progression has not been well defined. Here, we report that PIK3CA mutant tumor cells transmit oncogenic signals and result in malignant transformation of intestinal epithelial cells (IECs) via paracrine exosomal arachidonic acid (AA)-induced H3K4 trimethylation. Mechanistically, PIK3CA mutations sustain SGK3-FBW7-mediated stability of the cPLA2 protein, leading to the synthetic increase in AA, which is transported through exosome and accumulated in IECs. Transferred AA directly binds Menin and strengthens the interactions of Menin and MLL1/2 methyltransferase. Finally, the combination of VTP50469, an inhibitor of the Menin-MLL interaction, and alpelisib synergistically represses PDX tumors harboring PIK3CA mutations. Together, these findings unveil the metabolic link between PIK3CA mutant tumor cells and the IECs, highlighting AA as the potential target for the treatment of patients with CRC harboring PIK3CA mutations.
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Ácido Araquidónico , Transformación Celular Neoplásica , Ensamble y Desensamble de Cromatina , Fosfatidilinositol 3-Quinasa Clase I , Mutación , Fosfatidilinositol 3-Quinasa Clase I/genética , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Humanos , Ácido Araquidónico/metabolismo , Animales , Mutación/genética , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Ensamble y Desensamble de Cromatina/genética , Ratones , Línea Celular Tumoral , Colon/patología , Colon/metabolismo , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Exosomas/metabolismo , Exosomas/genética , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Histonas/metabolismo , Histonas/genéticaRESUMEN
Toll-like receptors (TLRs), especially TLR7, play an important role in systemic lupus erythematosus (SLE) pathogenesis. However, the regulatory mechanism underlying the abnormal activation of TLR pathways in patients with SLE has not been elucidated. Notably, accumulating evidence indicates that myeloid-derived suppressor cells (MDSCs) are important regulators of inflammation and autoimmune diseases. Compared with healthy control subjects, patients with SLE have a greater proportion of MDSCs among peripheral blood mononuclear cells (PBMCs); however, the effect of MDSCs on TLR7 pathway activation has not been determined. In the present study, lupus MDSCs significantly promoted TLR7 pathway activation in macrophages and dendritic cells (DCs), exacerbating the imiquimod-induced lupus model. RNA-sequencing analysis revealed significant overexpression of S100 calcium-binding protein A8 (S100A8) and S100A9 in MDSCs from diseased MRL/lpr mice. In vitro and in vivo studies demonstrated that S100A8/9 effectively promoted TLR7 pathway activation and that S100A8/9 deficiency reversed the promoting effect of MDSCs on TLR7 pathway activation in lupus. Mechanistically, MDSC-derived S100A8/9 upregulated interferon gamma (IFN-γ) secretion by macrophages and IFN-γ subsequently promoted TLR7 pathway activation in an autocrine manner. Taken together, these findings suggest that lupus MDSCs promote TLR7 pathway activation and lupus pathogenesis through the S100A8/9-IFN-γ axis. Our study identified an important target for SLE therapy.
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Calgranulina A , Calgranulina B , Lupus Eritematoso Sistémico , Células Supresoras de Origen Mieloide , Animales , Ratones , Células Dendríticas/metabolismo , Leucocitos Mononucleares/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/patología , Macrófagos/metabolismo , Ratones Endogámicos MRL lpr , Receptor Toll-Like 7/genética , Receptor Toll-Like 7/metabolismo , Calgranulina A/metabolismo , Calgranulina B/metabolismoRESUMEN
BACKGROUND: Tumor cells continue to evolve the metastatic potential in response to signals provided by the external microenvironment during metastasis. Platelets closely interact with tumor cells during hematogenous metastasis and facilitate tumor development. However, the molecular mechanisms underlying this process are not fully understood. METHODS: RNA-sequencing was performed to screen differentially expressed genes mediated by platelets. The effects of platelet and CD39 on tumor metastasis were determined by experimental metastasis models with WT, NCG and CD39-/- mice. RESULTS: RNA-sequencing results showed that platelets significantly up-regulated CD39 expression in tumor cells. CD39 is a novel immune checkpoint molecule and a key driver of immunosuppression. Our data provided evidence that the expression of CD39 was enhanced by platelets in a platelet-tumor cell contact dependent manner. Although the role of CD39 expressed by immune cells is well established, the effect of CD39 expressed by tumor cells on tumor cell behavior, anti-tumor immunity and tumor metastasis is unclear. We found that CD39 promoted tumor cell invasion, but had no effect on proliferation and migration. Notably, we showed that the ability of platelets to prime tumor cells for metastasis depends on CD39 in the experimental tumor metastasis model. CD39 silencing resulted in fewer experimental metastasis formation, and this anti-metastasis effect was significantly reduced in platelet-depleted mice. Furthermore, overexpression of CD39 in tumor cells promoted metastasis. In order to eliminate the effect of CD39 expressed in cells other than tumor cells, we detected tumor metastasis in CD39-/- mice and obtained similar results. Moreover, overexpression of CD39 in tumor cells inhibited antitumor immunity. Finally, the data from human samples also supported our findings. CONCLUSIONS: Our study shows that direct contact with platelets induces CD39 expression in tumor cells, leading to immune suppression and promotion of metastasis.
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Antígenos CD , Apirasa , Plaquetas , Metástasis de la Neoplasia , Animales , Apirasa/genética , Apirasa/metabolismo , Plaquetas/metabolismo , Plaquetas/patología , Ratones , Antígenos CD/genética , Antígenos CD/metabolismo , Humanos , Línea Celular Tumoral , Femenino , Ratones Noqueados , Movimiento Celular , Microambiente Tumoral/inmunología , Regulación Neoplásica de la Expresión GénicaRESUMEN
Fatty acid metabolism, particularly fatty acid synthesis, is a very important cellular physiological process in which nutrients are used for energy storage and biofilm synthesis. As a key enzyme in the fatty acid metabolism, fatty acid synthase (FASN) is receiving increasing attention. Although previous studies on FASN have mainly focused on various malignancies, many studies have recently reported that FASN regulates the survival, differentiation, and function of various immune cells, and subsequently participates in the occurrence and development of immune-related diseases. However, few studies to date systematically summarized the function and molecular mechanisms of FASN in immune cell biology and related diseases. In this review, we discuss the regulatory effect of FASN on immune cells, and the progress in research on the implications of FASN in immune-related diseases. Understanding the function of FASN in immune cell biology and related diseases can offer insights into novel treatment strategies for clinical diseases.
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Ácido Graso Sintasas , Lipogénesis , Ácido Graso Sintasas/genética , Ácido Graso Sintasas/metabolismo , Línea Celular Tumoral , Metabolismo de los Lípidos , Ácidos GrasosRESUMEN
Immune-mediated acute hepatic injury is characterized by the destruction of a large number of hepatocytes and severe liver function damage. Interleukin-28A (IL-28A), a member of the IL-10 family, is notable for its antiviral properties. However, despite advances in our understanding of IL-28A, its role in immune-mediated acute injury remains unclear. The present study investigated the role of IL-28A in concanavalin A (Con A)-induced acute immune liver injury. After Con A injection in mice, IL-28A level significantly increased. IL-28A deficiency was found to protect mice from acute liver injury, prolong survival time, and reduce serum aspartate aminotransferase and alanine aminotransferase levels. In contrast, recombinant IL-28A aggravated liver injury in mice. The proportion of activated M1 macrophages was significantly lower in the IL-28A-deficiency group than in the wild-type mouse group. In adoptive transfer experiments, M1 macrophages from WT could exacerbate mice acute liver injury symptoms in the IL-28A deficiency group. Furthermore, the expression of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), IL-12, IL-6, and IL-1ß, by M1 macrophages decreased significantly in the IL-28A-deficiency group. Western blotting demonstrated that IL-28A deficiency could limit M1 macrophage polarization by modulating the nuclear factor (NF)-κB, mitogen-activated protein kinase (MAPK), and interferon regulatory factor (IRF) signaling pathways. In summary, IL-28A deletion plays an important protective role in the Con A-induced acute liver injury model and IL-28A deficiency inhibits the activation of M1 macrophages by inhibiting the NF-κB, MAPK, and IRF signaling pathways. These results provide a potential new target for the treatment of immune-related hepatic injury.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Citocinas , Interferón lambda , Interleucinas , Animales , Ratones , Concanavalina A , Factores Reguladores del Interferón , Hígado , Macrófagos , Proteínas Quinasas Activadas por Mitógenos , Interferón lambda/genética , Interleucinas/genéticaRESUMEN
BACKGROUND: Cells and tissues, such as macrophages, express inducible nitric oxide synthase (INOS) after stimulation by certain factors. INOS helps mediate the macrophage inflammatory reaction, but few studies have explored how INOS affects macrophage function in nonalcoholic fatty liver disease (NAFLD). OBJECTIVE: This study investigated the role of INOS-mediated macrophage activity in NAFLD. METHODS: A high-fat diet was used to establish an NAFLD mouse model. After 12 weeks, blood was collected for immune cell and lipid analyses, and liver tissues were collected for pathological analyses with hematoxylin and eosin and Oil Red O staining. Peritoneal macrophages were extracted in situ, cultured in Dulbecco's modified Eagle's medium, and stimulated with palmitic acid to mimic in vivo conditions for further assays. Real-time polymerase chain reaction, western blot analysis, and immunofluorescence were used to verify the expression of target genes or proteins. RESULTS: In the NAFLD model, INOS expression in macrophages increased, and INOS knockdown significantly decreased the number of macrophages. Pathological examinations confirmed that INOS knockdown slowed NAFLD progression and macrophage infiltration during inflammation. INOS knockdown also enhanced phagocytosis and lipid transport by macrophages, and increased the expression of autophagy-related molecules in macrophages, which improved the autophagy level, promoted apoptotic cell degradation, and maintained intracellular environment homeostasis. CONCLUSIONS: These results indicate a correlation between INOS expression and macrophage function in NAFLD.
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Óxido Nítrico Sintasa de Tipo II , Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Autofagia , Inflamación/metabolismo , Lípidos , Macrófagos/metabolismo , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismoRESUMEN
Neutrophils participate in the pathogenesis of ulcerative colitis (UC) through regulating the intestinal homeostasis. Several inflammatory diseases are reported to be regulated by proline-rich tyrosine kinase 2B (PTK2B). However, the role of PTK2B in regulating the function of neutrophils and the pathogenesis of UC remains unknown. In this study, the mRNA and protein levels of PTK2B in the colonic tissues from UC patients were measured by using quantitative real-time polymerase chain reaction (qRT-PCR), western blotting, and immunohistochemistry. TAE226, a PTK2B inhibitor, was used to inhibit the activity of PTK2B in neutrophils, and then, the pro-inflammatory factors were analyzed by using qRT-PCR and ELISA. To determine the role of PTK2B in intestinal inflammation, a dextran sulfate sodium (DSS)-induced colitis model was established in PTK2B gene knockout (PTK2B KO) and wild-type (WT) mice. We found that compared with healthy donor controls, the expression level of PTK2B was significantly elevated in inflamed mucosa from UC patients. In addition, expression of PTK2B was positively correlated with the severity of disease. Pharmacological inhibition of PTK2B could markedly reduce the generation of reactive oxygen species (ROS), myeloperoxidase (MPO), and antimicrobial peptides (S100a8 and S100a9) in neutrophils. The vitro study showed that tumor necrosis factor (TNF)-α is involved in promoting the expression of PTK2B in neutrophils. As expected, UC patients treated with infliximab, an anti-TNF-α agent, showed significantly reduced level of PTK2B in neutrophils, as well as in the intestinal mucosa. Of note, compared with DSS-treated WT mice, DSS-treated PTK2B KO mice showed more severe colitis symptoms. Mechanistically, PTK2B could enhance neutrophil migration by regulating CXCR2 and GRK2 expression via the p38 MAPK pathway. Additionally, mice treated with TAE226 exhibited the same effects. In conclusion, PTK2B is involved in the pathogenesis of UC by promoting the migration of neutrophils and inhibiting mucosal inflammation, highlighting PTK2B as a new potential therapeutic target to treat UC.
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Colitis Ulcerosa , Quinasa 2 de Adhesión Focal , Animales , Ratones , Colitis Ulcerosa/metabolismo , Colon/metabolismo , Sulfato de Dextran/toxicidad , Modelos Animales de Enfermedad , Quinasa 2 de Adhesión Focal/genética , Quinasa 2 de Adhesión Focal/metabolismo , Inmunidad , Inflamación/metabolismo , Mucosa Intestinal/metabolismo , Neutrófilos/metabolismo , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , HumanosRESUMEN
Although psoriasis is classified as a T cell-mediated inflammatory disease, the contribution of myeloid cells to the pathogenesis of psoriasis is not fully understood. In the present study, we demonstrated that the expression of the anti-inflammatory cytokine interleukin-35 (IL-35) was significantly increased in patients with psoriasis with a marked increase in the number of myeloid-derived suppressor cells (MDSCs). Similar results were obtained in an imiquimod-induced psoriasis mouse model. IL-35 reduced the total number of MDSCs and their subtypes in the spleens and psoriatic skin lesions, ameliorating psoriasis. IL-35 also reduced the expression of inducible nitric oxide synthase in MDSCs, although it had no significant effect on interleukin-10 expression. Adoptive transfer of MDSCs from imiquimod-challenged mice aggravated the disease and weakened the effect of IL-35 in the recipient mice. In addition, mice transferred with MDSCs isolated from inducible nitric oxide synthase knockout mice had milder disease than those with wild-type MDSCs. Furthermore, wild-type MDSCs reversed the effects of IL-35, while MDSCs isolated from inducible nitric oxide synthase knockout mice did not affect IL-35 treatment. In summary, IL-35 may play a critical role in the regulation of iNOS-expressing MDSCs in the pathogenesis of psoriasis, highlighting IL-35 as a novel therapeutic strategy for patients with chronic psoriasis or other cutaneous inflammatory diseases.
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Células Supresoras de Origen Mieloide , Psoriasis , Animales , Ratones , Células Supresoras de Origen Mieloide/metabolismo , Imiquimod , Óxido Nítrico Sintasa de Tipo II/metabolismo , Psoriasis/metabolismo , Ratones Noqueados , Interleucinas/genética , Interleucinas/metabolismoRESUMEN
Interrupting the embryonic ectoderm development (EED)-H3K27me3 interaction represents a promising strategy to allosterically inhibit polycomb repressive complex 2 (PRC2) for cancer therapy. In this work, we report the structure-based design of new triazolopyrimidine-based EED inhibitors, which structurally feature the electron-rich indole ring at the C8 position. Particularly, ZJH-16 directly binds to EED (HTRF IC50 = 2.72 nM, BLI KD = 4.4 nM) and potently inhibits the growth of KARPAS422 and Pfeiffer cells. In both cells, ZJH-16 is selectively engaged with EED and reduces H3K27 trimethylation levels. ZJH-16 inhibits the gene silencing function of PRC2 in KARPAS422 cells. ZJH-16 possesses favorable pharmacokinetic (PK) profiles with an excellent oral bioavailability (F = 94.7%). More importantly, ZJH-16 shows robust tumor regression in the KARPAS422 xenograft model after oral administration with the tumor growth inhibition reaching nearly 100%. The robust antitumor efficacy and favorable PK profiles of ZJH-16 warrant further advanced preclinical development for lymphoma treatment.
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Histonas , Linfoma , Humanos , Histonas/metabolismo , Complejo Represivo Polycomb 2/metabolismoRESUMEN
Endotoxin shock remains one of the major causes of mortality worldwide. Pyruvate dehydrogenase kinase (PDK) 2 is an important regulatory enzyme involved in glucose metabolism. The purpose of this study was to determine the regulatory effect of PDK2 on LPS-induced endotoxin shock and explore the mechanisms in vivo and in vitro. Here, we showed that PDK2 contributed to Toll-like receptor (TLR)-mediated inflammation. Lipopolysaccharide (LPS) activation of TLR4 pathways resulted in PDK2 upregulation in macrophages and dendritic cells (DCs). PDK2 overexpression enhanced TLR4 signaling pathway activation, whereas downregulating PDK2 expression inhibited TLR4 signaling pathway activation. Pharmacological inhibition of PDK2 significantly decreased the mortality rate and alleviated pathological injury in the lungs and livers of LPS-challenged mice, while significantly suppressing proinflammatory cytokine production. Thus, we confirmed that PDK2 is involved in LPS-induced endotoxin shock by modulating TLR4-mitogen-activated protein kinase signaling and inducing the production of proinflammatory cytokines in macrophages and DCs. Our findings highlight the importance of PDK2 as a novel target to treat septic shock.
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Proteínas Quinasas Activadas por Mitógenos , Choque Séptico , Animales , Ratones , Lipopolisacáridos/farmacología , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Choque Séptico/metabolismo , Receptor Toll-Like 4/metabolismoRESUMEN
BACKGROUND: To determine whether SIRPα can be a diagnostic marker of pulmonary tuberculosis (PTB) and the molecular mechanism of SIRPα regulating macrophages to kill Mycobacterium tuberculosis (MTB). METHODS: Meta-analysis combined with subsequent qRT-PCR, western-blotting and flow cytometry assay were used to detect SIRPα expression in PTB patients. Cell-based assays were used to explore the regulation of macrophage function by SIRPα. SIRPα-/- and wide type macrophages transplanted C57BL/6J mice were used to determine the function of SIRPα on MTB infection in vivo. FINDINGS: SIRPα levels are closely correlated with the treatment outcomes among PTB patients. Cell-based assay demonstrated that MTB significantly induces the expression of SIRPα on macrophages. SIRPα deficiency enhances the killing ability of macrophages against MTB through processes that involve enhanced autophagy and reduced necroptosis of macrophages. Mechanistically, SIRPα forms a direct interaction with PTK2B through its intracellular C-terminal domain, thus inhibiting PTK2B activation in macrophages. Necroptosis inhibition due to SIRPα deficiency requires PTK2B activity. The transfer of SIRPα-deficient bone marrow-derived macrophages (BMDMs) into wild type mice resulted in a drop of bacterial load in the lungs but an enhancement of inflammatory lung damage, and the combination of ulinastatin and SIRPα-/-âWT treatment could decrease the inflammation and maintain the bactericidal capacity. INTERPRETATION: Our data define SIRPα a novel biomarker for tuberculosis infection and underlying mechanisms for maintaining macrophage homeostasis. FUNDING: This work was financially supported by the Chinese National Natural Science Foundation project (No.81401635). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
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Mycobacterium tuberculosis , Tuberculosis Pulmonar , Tuberculosis , Animales , Ratones , Autofagia/genética , Quinasa 2 de Adhesión Focal/metabolismo , Homeostasis , Macrófagos/metabolismo , Ratones Endogámicos C57BL , Necroptosis , Tuberculosis/microbiología , Tuberculosis Pulmonar/genética , Tuberculosis Pulmonar/metabolismo , HumanosRESUMEN
Polycomp group (PcG) proteins are members of highly conserved multiprotein complexes, recognized as gene transcriptional repressors during development and shown to play a role in various physiological and pathological processes. PcG proteins consist of two Polycomb repressive complexes (PRCs) with different enzymatic activities: Polycomb repressive complexes 1 (PRC1), a ubiquitin ligase, and Polycomb repressive complexes 2 (PRC2), a histone methyltransferase. Traditionally, PRCs have been described to be associated with transcriptional repression of homeotic genes, as well as gene transcription activating effects. Particularly in cancer, PRCs have been found to misregulate gene expression, not only depending on the function of the whole PRCs, but also through their separate subunits. In this review, we focused especially on the recent findings in the transcriptional regulation of PRCs, the oncogenic and tumor-suppressive roles of PcG proteins, and the research progress of inhibitors targeting PRCs.
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Proteínas de Drosophila , Neoplasias , Humanos , Neoplasias/genética , Complejo Represivo Polycomb 1/genética , Complejo Represivo Polycomb 2/genética , Proteínas del Grupo Polycomb/genética , Proteínas del Grupo Polycomb/metabolismoRESUMEN
Toll-like receptors (TLRs) are the first line of defense in the immune system, whose activation plays a key role in the pathogenesis of inflammation and autoimmunity. TLRs can activate a variety of immune cells such as macrophages and dendritic cells, which produce proinflammatory cytokines, chemokines, and co-stimulatory molecules that lead to the development of inflammation and autoimmune diseases. As a nonreceptor tyrosine kinase, ACK1 is involved in multiple signaling pathways and physiological processes. However, the roles of ACK1 in the activation of TLR pathways and in the pathogenesis of inflammation and autoimmune diseases have not yet been reported. We found that the expression of ACK1 could be upregulated by TLR pathways in vivo and in vitro. Intriguingly, overexpression of ACK1 significantly promoted the activation of TLR4, TLR7, and TLR9 pathways, while knockdown of ACK1 or the use of the ACK1 inhibitor AIM-100 significantly inhibited the activation of TLR4, TLR7, and TLR9 pathways. In vivo studies showed that the inhibition of ACK1 activity by AIM-100 could significantly protect mice from the TLR4 agonist lipopolysaccharide (LPS)-mediated endotoxin shock and alleviate the condition of imiquimod-mediated lupus-prone mice and MRL/lpr mice. In summary, ACK1 participates in TLR-mediated inflammation and autoimmunity and has great potential in controlling inflammation and alleviating autoimmune diseases.
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Enfermedades Autoinmunes , Autoinmunidad , Animales , Enfermedades Autoinmunes/etiología , Inflamación , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos MRL lpr , Transducción de Señal , Receptor Toll-Like 4 , Receptor Toll-Like 7/genética , Receptor Toll-Like 7/metabolismo , Receptor Toll-Like 9/metabolismo , Receptores Toll-LikeRESUMEN
INTRODUCTION: Acute liver inflammatory reactions contribute to many health problems; thus, it is critical to understand the underlying pathogenic mechanisms of acute hepatitis. In this study, an experimental in vivo model of concanavalin A (ConA)-induced hepatitis was used. MATERIALS AND METHODS: C57BL/6 (wild-type, WT) or inducible nitric oxide synthase-deficient (iNOS-/- ) mice were injected with PBS or 15 mg/kg ConA via tail vein. Detection of liver injury by histological examination and apoptosis, and flow cytometry to detect the effect of immune cells on liver injury. RESULTS: iNOS-/- mice had lower levels of the liver enzymes aspartate aminotransferase and alanine aminotransferase, suggesting that they were protected against ConA-induced pathological liver injury and that iNOS participated in the regulation of hepatitis. Furthermore, iNOS deficiency was found to lower CD86 expression and suppressed the messenger RNA levels of inflammatory factors in the liver. In vitro experiments also demonstrated that iNOS deficiency suppressed the sequential phosphorylation of the mitogen-activated protein kinase pathway cascade, thereby inhibiting the M1 polarization of macrophages and consequently suppressing the transcription of inflammation factors. CONCLUSION: iNOS may contribute to ConA-induced inflammation by promoting the activation of proinflammatory macrophages.
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Hepatitis , Animales , Concanavalina A/metabolismo , Concanavalina A/toxicidad , Hepatitis/etiología , Hepatitis/metabolismo , Hepatitis/patología , Inflamación , Macrófagos , Ratones , Ratones Endogámicos C57BL , Óxido Nítrico Sintasa de Tipo II/genética , Óxido Nítrico Sintasa de Tipo II/metabolismoRESUMEN
BACKGROUND: Liver injury is a serious threat to human health that has become a worldwide problem. To date, there is still no effective treatment strategy. In the present study, we examined the protective effects of Human liver stem cells (HLSCs) against concanavalin A (Con A)-induced acute liver injury. METHODS: Isolated HLSCs were characterized by microscopy, functional assays, and gene expression. HLSCs or HLSCs culture medium were transplanted in mice for 12 h and subsequently challenged with Con A via tail-vein injection. The effects were evaluated through survival rate, histology, blood tests, TUNEL assay, quantitative RT-PCR and flow cytometry. CellTracker™ CM-Dil labled HLSCs were tracked by fluorescence microscope. RESULTS: Transplantation of HLSCs reduced the mortality rate, reduced the levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and total bilirubin (TBIL), narrowed the area of liver necrosis, and inhibited hepatocyte apoptosis induced by Con A. Injection of HLSCs culture medium could also alleviate Con A-induced liver injury. Of note, HLSCs-transplanted mice exhibited lower frequencies of Th17 cells and higher frequencies of Tregs in their liver and spleen following Con A injection. Moreover, transplantation of HLSCs significantly reduced the expression of IL-17A, IL-17F and ROR-γt induced by Con A, while reversed Con A-induced downregulation of Foxp3 expression and IL-10. CONCLUSIONS: HLSCs protect mice from immune-mediated liver injury by regulating the balance of Treg/Th17 cells, suggesting that transplantation of HLSCs is a potential and effective therapeutic method for amelioration of liver injury.
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Enfermedad Hepática Crónica Inducida por Sustancias y Drogas , Células Madre , Linfocitos T Reguladores , Células Th17 , Animales , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Crónica Inducida por Sustancias y Drogas/patología , Concanavalina A , Humanos , Hígado/citología , Hígado/patología , Ratones , Células Madre/citologíaRESUMEN
Liver fibrosis is a very common health problem and currently lacks effective treatments. Cullin RING E3 ligases (CRLs) regulate the turnover of â¼20% of mammalian cell proteins. Neddylation, the process by which NEDD8 is covalently attached to cullin proteins through sequential enzymatic reactions, is critical for the activation of CRLs and was recently found to be elevated in liver fibrosis. NEDD8-activating enzyme E1-specific inhibition led to the reduced liver damage characterized by decreased apoptosis, inflammation, and fibrosis. However, the relevance of a co-E3 ligase, DCN1, in liver fibrosis remains unclear. Here, a novel and potent DCN1-UBC12 interaction inhibitor HZX-960 was discovered with an IC50 value of 9.37 nmol/L, which could inhibit the neddylation of cullin3. Importantly, we identified that HZX-960 treatment could attenuate transforming growth factor ß-induced liver fibrotic responses by reducing the deposition of collagen I and α-smooth muscle actin, and upregulating cellular NF-E2-related factor 2, hemeoxygenase 1, and NADPH quinone oxidoreductase-1 levels in two hepatic stellate cell lines. Additionally, DCN1 was shown to be unregulated in CCl4-induced mice liver tissue, and liver fibrotic signaling in mice was reduced by HZX-960. Therefore, our data demonstrated that HZX-960 possessed anti-liver fibrosis ability and that DCN1 may be a potential therapeutic target for liver fibrosis treatment.
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Inhibidores Enzimáticos , Cirrosis Hepática , Enzimas Ubiquitina-Conjugadoras , Ubiquitina-Proteína Ligasas , Animales , Proteínas Cullin/metabolismo , Inhibidores Enzimáticos/farmacología , Cirrosis Hepática/tratamiento farmacológico , Ratones , Enzimas Ubiquitina-Conjugadoras/antagonistas & inhibidores , Ubiquitina-Proteína Ligasas/antagonistas & inhibidores , UbiquitinaciónRESUMEN
The type III interferon family (IFN-III), including IFN-λ3 [interleukin (IL)-28B], has antiviral, anti-tumor, and immunomodulatory activities. Although the IL-28B anti-tumor effect has been extensively explored, its underlying mechanism remains unclear. Here, we explored IL-28B effects on colon cancer. Our results show that IL-28B significantly inhibits colon cancer progression in a mouse MC38 tumor cell colonization model and colitis-associated colorectal tumor model. Interestingly, IL-28B does not directly promote apoptosis or inhibit MC38 tumor cell proliferation in vitro. Rather, IL-28B treatment has indirect anti-tumor activity by downregulating tumor-associated macrophages. Furthermore, IL-28B inhibits M2 macrophage polarization in vitro, while also halting M2 macrophage differentiation predominantly via inhibition of the signal transducer and activator of transcription (STAT)3 and c-Jun N-terminal kinase (JNK) signaling pathways. Our findings revealed that IL-28B inhibits M2 macrophages in the tumor microenvironment to delay colon cancer progression. These findings provide novel evidence of IL-28B anti-tumor and immunomodulatory activities.
Asunto(s)
Neoplasias del Colon , Macrófagos Asociados a Tumores , Animales , Antivirales/farmacología , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Macrófagos , Ratones , Transducción de Señal , Microambiente TumoralRESUMEN
Interferon-I (IFN-I) signaling pathway plays a vital role in the differentiation of germinal center B cells and the pathogenesis of systemic lupus erythematosus (SLE). Therefore, targeting the IFN-I signaling pathway could serve as an effective treatment strategy in SLE. Arctigenin is an active ingredient present in the seeds of Arctium lappa L. It has been reported to act as a negative regulator of inflammatory responses. However, the role of arctigenin remains unknown in the regulation process of the IFN-I-mediated differentiation of germinal center B cells and the pathogenesis of SLE. In the present study, we demonstrated that arctigenin alleviated the progression of spontaneous lupus in MRL/lpr mice and imiquimod-mediated lupus mice. Especially, arctigenin significantly reduced the proportions of germinal center B cells (7.1%, vs. 5.12%, p < 0.01), follicular helper T cells (11.49%, vs. 5.53%, p < 0.05), and plasma cells (2.44%, vs. 1.39%, p < 0.01) in the lupus-prone mice. In vitro studies have shown that arctigenin significantly inhibited the IFN-α-induced CD69 and interferon-stimulated gene (ISG) expressions along with the phosphorylation of JAK1 and STAT1 by nearly half in murine B cells via activating PP2A. Overall, these data highlighted the role of arctigenin in regulating the IFN-I-mediated differentiation of germinal center B cells and the pathogenesis of SLE. Thus, arctigenin may be used as a potentially effective therapeutic target for the treatment of SLE.