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Alveolar macrophages (AMs) are lower-airway resident myeloid cells and are among the first to respond to inhaled pathogens. Here, we interrogate AM innate sensing to Pathogen Associated Molecular Patterns (PAMPs) and determine AMs have decreased responses to low-dose LPS compared to other macrophages, as measured by TNF, IL-6, Ifnb, and Ifit3. We find the reduced response to low-dose LPS correlates with minimal TLR4 and CD14 surface expression, despite sufficient internal expression of TLR4. Additionally, we find that AMs do not produce IL-10 in response to a variety of PAMPs due to low expression of transcription factor c-Maf and that lack of IL-10 production contributes to an enhancement of pro-inflammatory responses by Type I IFN. Our findings demonstrate that AMs have cell-intrinsic dampened responses to LPS, which is enhanced by type I IFN exposure. These data implicate conditions where AMs may have reduced or enhanced sentinel responses to bacterial infections.
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OBJECTIVES: Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease, of which the pathogens is remains obscure. Viral infection, particularly Epstein Barr viru (EBV) infection, has been considered a common pathogenic factor. This study suggests that c-Maf may be an important target in T cell differentiation during SLE progression, providing a potentially new perspective on the role of viral infection in the pathogenesis of autoimmune diseases. METHODS: Cytokines of EBV-infected SLE patients were measured by ELISA and assessed in conjunction with their clinical data. IFN-α, c-Maf, and the differentiation of Th17/Treg cells in SLE patients and MRL/LPR mice were analyzed using FCM, WB, RT-PCR, etc. Following the infection of cells and mice with EBV or viral mimic poly (dA:dT), the changes of the aforementioned indicators were investigated. The relationship among IFN-α, STAT3, c-Maf and Th17 cells was determined by si-RNA technique. RESULTS: Many SLE patients are found to be complicated by viral infections; Further, studies have demonstrated that viral infection, especially EBV, is involved in SLE development. This study showed that viral infections might promote IFN-α secretion, inhibit c-Maf expression by activating STAT3, increase Th17 cell differentiation, and lead to the immune imbalance of Th17/Treg cells, thus playing a role in the onset and progression of SLE. CONCLUSION: This study demonstrates that EBV infections may contribute to SLE development by activating STAT3 through IFN-α, inhibiting c-Maf, and causing Th17/Treg immune imbalance. Our work provided a new insight into the pathogenesis and treatment of SLE.
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Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Interferón-alfa , Lupus Eritematoso Sistémico , Ratones Endogámicos MRL lpr , Proteínas Proto-Oncogénicas c-maf , Linfocitos T Reguladores , Células Th17 , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/virología , Células Th17/inmunología , Humanos , Animales , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/virología , Infecciones por Virus de Epstein-Barr/complicaciones , Linfocitos T Reguladores/inmunología , Ratones , Interferón-alfa/inmunología , Interferón-alfa/metabolismo , Femenino , Adulto , Herpesvirus Humano 4/inmunología , Proteínas Proto-Oncogénicas c-maf/inmunología , Proteínas Proto-Oncogénicas c-maf/genética , Masculino , Diferenciación Celular/inmunología , Progresión de la Enfermedad , Persona de Mediana Edad , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/inmunología , Adulto JovenRESUMEN
BACKGROUND: Hypertrophic scar (HS) is caused by the abnormal proliferation of fibroblasts and excessive deposition of extracellular matrix (ECM). Emerging evidence demonstrates that c-Maf positive M2 macrophages were mainly located in the hypertrophic scar tissues of proliferative phase. But whether c-Maf positive M2 macrophages can promote hypertrophic scar formation through modulating hypertrophic scar fibroblasts remains elusive. AIMS: The aim of this study is to investigate the effects of c-Maf positive M2 macrophages on the biological behaviors and functions of hypertrophic scar fibroblasts and the potential mechanism. METHODS: HE and Masson trichrome staining were used to examine the histological features of human hypertrophic scar. Immunofluorescence staining was employed to label and quantify the c-Maf+ /CD68+ M2 macrophages. CCK8, wound healing, and transwell assays were utilized to test the effects of c-Maf overexpressed M2 macrophages or the cell culture supernatants on the proliferation and migration of hypertrophic scar derived fibroblasts (HFBs) and normal skin derived fibroblasts (NFBs). Western blot and qPCR were harnessed to test the expressions of COL1, COL3, and α-SMA in the co-cultivated fibroblasts and TGF-ß1 in the c-Maf overexpressed M2 macrophages. RESULTS: Increased number of c-Maf+ /CD68+ M2 macrophages were found in HS in contrast to the normal skin (NS). Elevated proliferation and migration were observed in the HFBs or NFBs co-cultured with c-Maf overexpressed macrophages or the cell culture supernatants. A higher mRNA and protein expressions of COL1, COL3, and α-SMA were recorded in the HFBs co-cultured with c-Maf overexpressed macrophages or treated with its culture supernatants. In addition, augmented mRNA and protein expressions of TGF-ß1 were also investigated in the c-Maf overexpressed macrophages. CONCLUSION: c-Maf positive macrophages promote hypertrophic scar formation through regulating HFBs proliferation, migration, and ECM deposition via the secreted TGF-ß1.
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Cicatriz Hipertrófica , Humanos , Cicatriz Hipertrófica/patología , Matriz Extracelular/metabolismo , Fibroblastos , Macrófagos/metabolismo , Macrófagos/patología , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador beta1/metabolismoRESUMEN
Multiple myeloma (MM) is a prevalent plasma cell malignancy in the blood system that remains incurable. Given the abnormally high expression of c-Maf in most MM patients, targeting c-Maf presents an attractive therapeutic approach for treating MM malignancies. In this study, we employed a combined strategy involving molecular docking-based virtual screening, molecular dynamics (MD) simulation, and molecular mechanics/generalized Born surface area (MM/GBSA) free energy calculation on existing FDA-approved drugs. Six compounds were selected for further experimental assay: vemurafenib, sorafenib, sildenafil, fluvastatin, erlotinib, and glimepiride. Among these compounds, sorafenib and glimepiride exhibited significant inhibition of myeloma cell proliferation in the RPMI-8226 cell line. Moreover, both compounds simultaneously downregulated c-Maf protein expression to induce G1 phase arrest and apoptosis in myeloma cells. Collectively, sorafenib and glimepiride may be considered promising candidates for developing more potent c-Maf inhibitors in the future.
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Simulación de Dinámica Molecular , Mieloma Múltiple , Compuestos de Sulfonilurea , Humanos , Simulación del Acoplamiento Molecular , Sorafenib/farmacología , Mieloma Múltiple/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-mafRESUMEN
BACKGROUND: Tumor-associated macrophages (TAMs) are an immune component of the cutaneous malignant melanoma (CMM) microenvironment and affect tumor growth. TAMs can polarize into different phenotypes, that is, proinflammatory M1 and anti-inflammatory M2 macrophages. However, the role of the macrophage phenotype in CMM remains unclear. METHODS: We examined 88 patients with CMM. Tissue microarrays were constructed, and the density of M1 and M2 macrophages was analyzed by immunohistochemistry. Immune cells coexpressing CD68 and phosphorylated signal transducer and activator of transcription 1 (pSTAT1) were considered M1 macrophages, whereas those coexpressing CD68 and c-macrophage activating factor (c-Maf) were defined as M2 macrophages. These TAMs were counted, and the relationships between the density of M1 and M2 macrophages and clinicopathological factors including prognosis were investigated. RESULTS: The CD68/c-Maf score ranged from 0 to 34 (median: 5.5). The patients were divided based on the median score into the CD68/c-Maf high (≥5.5) and low (<5.5) expression groups. Univariate and multivariate analyses revealed that CD68/c-Maf expression was an independent predictive factor for progression-free survival and an independent prognostic factor for overall survival. CD68/pSTAT1 expression was found in only two patients. CONCLUSION: We suggest that CD68/pSTAT1 coexpression is rarely observed in patients with CMM, and high CD68/c-Maf expression is a predictor of worse prognosis in these patients.
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Melanoma , Neoplasias Cutáneas , Humanos , Melanoma Cutáneo Maligno , Macrófagos Asociados a Tumores/metabolismo , Macrófagos Asociados a Tumores/patología , Antígenos CD/metabolismo , Melanoma/metabolismo , Neoplasias Cutáneas/patología , Pronóstico , Microambiente Tumoral , Antígenos de Diferenciación Mielomonocítica/metabolismoRESUMEN
Commensal microbes induce cytokine-producing effector tissue-resident CD4+ T cells, but the function of these T cells in mucosal homeostasis is not well understood. Here, we report that commensal-specific intestinal Th17 cells possess an anti-inflammatory phenotype marked by expression of interleukin (IL)-10 and co-inhibitory receptors. The anti-inflammatory phenotype of gut-resident commensal-specific Th17 cells was driven by the transcription factor c-MAF. IL-10-producing commensal-specific Th17 cells were heterogeneous and derived from a TCF1+ gut-resident progenitor Th17 cell population. Th17 cells acquired IL-10 expression and anti-inflammatory phenotype in the small-intestinal lamina propria. IL-10 production by CD4+ T cells and IL-10 signaling in intestinal macrophages drove IL-10 expression by commensal-specific Th17 cells. Intestinal commensal-specific Th17 cells possessed immunoregulatory functions and curbed effector T cell activity in vitro and in vivo in an IL-10-dependent and c-MAF-dependent manner. Our results suggest that tissue-resident commensal-specific Th17 cells perform regulatory functions in mucosal homeostasis.
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Microbioma Gastrointestinal , Células Th17 , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , AntiinflamatoriosRESUMEN
Large musculoaponeurotic fibrosarcoma (MAF) transcription factors contain acidic, basic, and leucine zipper regions. Four types of MAF have been elucidated in mice and humans, namely c-MAF, MAFA, MAFB, and NRL. This review aimed to elaborate on the functions of MAF transcription factors that have been studied in vivo so far, as well as describe the pathology of human patients and corresponding mouse models with c-MAF, MAFA, and MAFB point mutations. To identify the functions of MAF transcription factors in vivo, we generated genetically modified mice lacking c-MAF, MAFA, and MAFB and analyzed their phenotypes. Further, in recent years, c-MAF, MAFA, and MAFB have been identified as causative genes underpinning many rare diseases. Careful observation of human patients and animal models is important to examine the pathophysiological mechanisms underlying these conditions for targeted therapies. Murine models exhibit phenotypes similar to those of human patients with c-MAF, MAFA, and MAFB mutations. Therefore, generating these animal models emphasizes their usefulness for research uncovering the pathophysiology of point mutations in MAF transcription factors and the development of etiology-based therapies.
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Factores de Transcripción Maf de Gran Tamaño , Factores de Transcripción , Humanos , Ratones , Animales , Factores de Transcripción/genética , Factores de Transcripción Maf de Gran Tamaño/genética , Factor de Transcripción MafB/genética , Insulina/genética , Mutación PuntualRESUMEN
The γδT-cells recognize infected or transformed cells. However, unlike αßT-cells, γδT-cells are innate-like immune cells, with no major histocompatibility complex restriction requirements. γδT-cells are the main population of intestinal intraepithelial lymphocytes (IELs) and are associated with the antitumor immune response, particularly in colorectal cancer (CRC). Although CD8+ T-cells exhibit dysfunction and even exhaustion in the tumor microenvironment (TME), which contributes to tumor immune escape, whether the same applies to tumor-infiltrating (TI)-γδT-cells is not completely understood. Here, we sought to investigate the expression pattern of inhibitory receptors and functional state of TI-γδT-cells, and reveal the features of exhausted TI-γδT-cells in the CRC TME. We demonstrated that TI-γδT-cells exhibited exhaustion phenotypes and displayed more severe functional exhaustion than TI-CD8+ T-cells or NK-cells in the TME of CRC. In addition, scRNA-seq analysis of TI-γδT-cells revealed three exhausted subsets with remarkable heterogeneity. The presence of three heterogeneous exhausted γδT-cell (Tex) populations, including Texprog , Textran and Texterm were further confirmed by flow cytometry, on the basis of PD-1 and TIM-3 expression. Finally, we revealed that c-Maf not only contributed to γδT-cell exhaustion via upregulation of inhibitory receptors, but also involved in the exhaustion of CD8+ T and NK-cells. c-Maf may also be an important contributor to γδT-cell exhaustion in CRC patients. These findings indicated that TI-γδT-cells exhibit phenotypic and functional exhaustion in the CRC TME. The revealed features of exhausted TI-γδT-cells may provide help for understanding the mechanisms and the association of γδT-cell exhaustion with tumor development and pathogenesis.
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Neoplasias Colorrectales , Linfocitos Intraepiteliales , Humanos , Linfocitos T CD8-positivos , Células Asesinas Naturales/patología , Neoplasias Colorrectales/patología , Microambiente Tumoral , Linfocitos Infiltrantes de TumorRESUMEN
Congenital cataract (CC) is regarded as the most common hereditary ophthalmic disease in children. Mutations in CC-associated genes play important roles in CC formation, which provides the basis for molecular diagnosis and therapy. Among these CC-associated genes, v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog (c-MAF) is considered an important transcription factor for eye and lens development. In this study, we recruited a three-generation Chinese Han family with CC. Gene sequencing revealed a novel duplication mutation in c-MAF (NM_005360.5: c.177dup) that caused frameshifting at residue 60 (p. M60fs) of c-MAF. Additionally, in the patient blood samples, the expression levels of related crystallin and noncrystallin genes confirmed that this novel duplication variant impaired the transactivation of c-MAF. Further functional analyses suggested that the c-MAF mutant induces the transcriptional inhibition of CRYAA and CRYGA and subsequently influences ME and G6PD expression levels, ultimately resulting in ROS generation and further leading to cell apoptosis via mitochondria-dependent pathways. In conclusion, we report a novel c-MAF heterozygous mutation that plays a vital role in CC formation in a Chinese family, broadening the genetic spectrum of CC.
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Catarata , Cristalinas , Niño , Humanos , Apoptosis/genética , Catarata/genética , Catarata/congénito , Catarata/diagnóstico , Cristalinas/genética , Mutación , LinajeRESUMEN
In innate immune cells, the transcription factor cellular musculoaponeurotic fibrosarcoma (c-Maf) influences cell fate and function through molecular and metabolic programming, thereby influencing immune homeostasis and antitumor immunity. We discuss recent c-Maf landmark discoveries with a focus on the immunosuppressive tumor microenvironment (TME) and provide a new perspective on c-Maf-targeted cancer immunotherapy.
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Fibrosarcoma , Factores de Transcripción , Humanos , Regulación de la Expresión Génica , Inmunoterapia , Macrófagos , Microambiente TumoralRESUMEN
Multiple myeloma (MM) is a hematologic malignancy derived from clonal expansion of plasma cells within the bone marrow and it may progress to the extramedullary region in late stage of the disease course. c-Maf, an oncogenic zipper leucine transcription factor, is overexpressed in more than 50% MM cell lines and primary species in association with chromosomal translocation, aberrant signaling transduction and modulation of stability. By triggering the transcription of critical genes including CCND2, ITGB7, CCR1, ARK5, c-Maf promotes MM progress, proliferation, survival and chemoresistance. Notably, c-Maf is usually expressed at the embryonic stage to promote cell differentiation but less expressed in healthy adult cells. c-Maf has long been proposed as a promising therapeutic target of MM and a panel of small molecule compounds have been identified to downregulate c-Maf and display potent anti-myeloma activities. In the current article, we take a concise summary on the advances in c-Maf biology, pathophysiology, and targeted drug discovery in the potential treatment of MM.
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Mieloma Múltiple , Médula Ósea/patología , Carcinogénesis/metabolismo , Humanos , Factor de Transcripción MafF/metabolismo , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/genética , Mieloma Múltiple/metabolismo , Células PlasmáticasRESUMEN
Group-2 innate lymphoid cells (ILC2s), which are involved in type 2 inflammatory diseases such as allergy, can exhibit immunological memory, but the basis of this ILC2 "trained immunity" has remained unclear. Here, we found that stimulation with IL-33/IL-25 or exposure to the allergen papain induces the expression of the transcription factor c-Maf in mouse ILC2s. Chronic papain exposure results in high production of IL-5 and IL-13 cytokines and lung eosinophil recruitment, effects that are blocked by c-Maf deletion in ILCs. Transcriptomic analysis revealed that knockdown of c-Maf in ILC2s suppresses expression of type 2 cytokine genes, as well as of genes linked to a memory-like phenotype. Consistently, c-Maf was found highly expressed in human adult ILC2s but absent in cord blood and required for cytokine production in isolated human ILC2s. Furthermore, c-Maf-deficient mouse or human ILC2s failed to exhibit strengthened ("trained") responses upon repeated challenge. Thus, the expression of c-Maf is indispensable for optimal type 2 cytokine production and proper memory-like responses in group-2 innate lymphoid cells.
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Inmunidad Innata , Linfocitos , Animales , Citocinas/metabolismo , Humanos , Interleucina-33/genética , Interleucina-33/metabolismo , Pulmón/metabolismo , Linfocitos/metabolismo , Ratones , Papaína/metabolismo , Proteínas Proto-Oncogénicas c-maf/metabolismoRESUMEN
Asthmatic airway inflammation is divided into two typical endotypes: Th2-mediated eosinophilic and Th1- or Th17-mediated neutrophilic airway inflammation. The miRNA miR-155 has well-documented roles in the regulation of adaptive T-cell responses and innate immunity. However, no specific cell-intrinsic role has yet been elucidated for miR-155 in T cells in the course of Th2-eosinophilic and Th17-neutrophilic airway inflammation using actual in vivo asthma models. Here, using conditional KO (miR155ΔCD4 cKO) mice that have the specific deficiency of miR-155 in T cells, we found that the specific deficiency of miR-155 in T cells resulted in fully suppressed Th2-type eosinophilic airway inflammation following acute allergen exposure, as well as greatly attenuated the Th17-type neutrophilic airway inflammation induced by repeated allergen exposure. Furthermore, miR-155 in T cells appeared to regulate the expression of several different target genes in the functional activation of CD4+ Th2 and Th17 cells. To be more precise, the deficiency of miR-155 in T cells enhanced the expression of c-Maf, SOCS1, Fosl2 and Jarid2 in the course of CD4+ Th2 cell activation, while C/EBPß was highly enhanced in CD4+ Th17 cell activation in the absence of miR-155 expression. Conclusively, our data revealed that miR-155 could promote Th2 and Th17-mediated airway inflammation via the regulation of several different target genes, depending on the context of asthmatic diseases. Therefore, these results provide valuable insights into actual understanding of specific cell-intrinsic role of miR-155 in eosinophilic and neutrophilic airway inflammation for the development of fine-tune therapeutic strategies.
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Asma , MicroARNs , Factores de Transcripción , Alérgenos , Animales , Asma/inmunología , Modelos Animales de Enfermedad , Inflamación/inmunología , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Complejo Represivo Polycomb 2/metabolismo , Células Th17 , Células Th2 , Factores de Transcripción/metabolismoRESUMEN
The liver vascular network is patterned by sinusoidal and hepatocyte co-zonation. How intra-liver vessels acquire their hierarchical specialized functions is unknown. We study heterogeneity of hepatic vascular cells during mouse development through functional and single-cell RNA-sequencing. The acquisition of sinusoidal endothelial cell identity is initiated during early development and completed postnatally, originating from a pool of undifferentiated vascular progenitors at E12. The peri-natal induction of the transcription factor c-Maf is a critical switch for the sinusoidal identity determination. Endothelium-restricted deletion of c-Maf disrupts liver sinusoidal development, aberrantly expands postnatal liver hematopoiesis, promotes excessive postnatal sinusoidal proliferation, and aggravates liver pro-fibrotic sensitivity to chemical insult. Enforced c-Maf overexpression in generic human endothelial cells switches on a liver sinusoidal transcriptional program that maintains hepatocyte function. c-Maf represents an inducible intra-organotypic and niche-responsive molecular determinant of hepatic sinusoidal cell identity and lays the foundation for the strategies for vasculature-driven liver repair.
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Capilares , Células Endoteliales , Animales , Endotelio , Hígado/patología , Cirrosis Hepática/patología , Regeneración Hepática , Ratones , Proteínas Proto-Oncogénicas c-mafRESUMEN
Regulatory B cells (Bregs) have been highlighted in very different pathology settings including autoimmune diseases, allergy, graft rejection, and cancer. Improving tools for the characterization of Bregs has become the main objective especially in humans. Transitional, mature B cells and plasma cells can differentiate into IL-10 producing Bregs in both mice and humans, suggesting that Bregs are not derived from unique precursors but may arise from different competent progenitors at unrestricted development stages. Moreover, in addition to IL-10 production, regulatory B cells used a broad range of suppressing mechanisms to modulate the immune response. Although Bregs have been consistently described in the literature, only a few reports described the molecular aspects that control the acquisition of the regulatory function. In this manuscript, we detailed the latest reports describing the control of IL-10, TGFß, and GZMB production in different Breg subsets at the molecular level. We focused on the understanding of the role of the transcription factors STAT3 and c-MAF in controlling IL-10 production in murine and human B cells and how these factors may represent an important crossroad of several key drivers of the Breg response. Finally, we provided original data supporting the evidence that MAF is expressed in human IL-10- producing plasmablast and could be induced in vitro following different stimulation cocktails. At steady state, we reported that MAF is expressed in specific human B-cell tonsillar subsets including the IgD+ CD27+ unswitched population, germinal center cells and plasmablast.
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Enfermedades Autoinmunes , Linfocitos B Reguladores , Animales , Enfermedades Autoinmunes/patología , Interleucina-10 , Recuento de Linfocitos , Ratones , Células Plasmáticas , Proteínas Proto-Oncogénicas c-maf/genéticaRESUMEN
BACKGROUND: Schizophrenia is a severely multifactorial neuropsychiatric disorder, and the majority of cases are due to genetic variations. In this study, we evaluated the genetic association between the C-Maf-inducing protein (CMIP) gene and schizophrenia in the Han Chinese population. METHODS: In this case-control study, 761 schizophrenia patients and 775 healthy controls were recruited. Tag single-nucleotide polymorphisms (SNPs; rs12925980, rs2287112, rs3751859 and rs77700579) from the CMIP gene were genotyped via matrix-assisted laser desorption/ionization time of flight mass spectrometry. We used logistic regression to estimate the associations between the genotypes/alleles of each SNP and schizophrenia in males and females, respectively. The in-depth link between CMIP and schizophrenia was explored through linkage disequilibrium (LD) and further haplotype analyses. False discovery rate correction was utilized to control for Type I errors caused by multiple comparisons. RESULTS: There was a significant difference in rs287112 allele frequencies between female schizophrenia patients and healthy controls after adjusting for multiple comparisons (χ2 = 12.296, P adj = 0.008). Females carrying minor allele G had 4.445 times higher risk of schizophrenia compared with people who carried the T allele (OR = 4.445, 95% CI [1.788-11.046]). Linkage-disequilibrium was not observed in the subjects, and people with haplotype TTGT of rs12925980-rs2287112-rs3751859-rs77700579 had a lower risk of schizophrenia (OR = 0.42, 95% CI [0.19-0.94]) when compared with CTGA haplotypes. However, the association did not survive false discovery rate correction. CONCLUSION: This study identified a potential CMIP variant that may confer schizophrenia risk in the female Han Chinese population.
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Immune response control is critical as excessive cytokine production can be detrimental and damage the host. Interleukin-10 (Il-10), an anti-inflammatory cytokine produced primarily by macrophages, is a key regulator that counteracts and controls excessive inflammatory response. Il-10 expression is regulated through the transcription factor c-Maf. Another regulator of Il-10 production is p35, an activator of the cyclin-dependent kinase 5 (Cdk5), which decreases Il-10 production in macrophages, thus increasing inflammation. However, Cdk5 regulation of c-Maf and the involvement of Il-10 production in macrophages has not yet been investigated. We used in vitro primary bone marrow-derived macrophages (BMDMs) lacking Cdk5, stimulated them with lipopolysaccharid (LPS) and observed increased levels of c-Maf and Il-10. In an in vivo mouse model of LPS-induced endotoxemia, mice lacking Cdk5 in macrophages showed increased levels of c-Maf and elevated levels of Il-10 in lungs as well as in plasma, resulting in ameliorated survival. Taken together, we identified Cdk5 as a potential novel regulator of Il-10 production through c-Maf in macrophages under inflammatory conditions. Our results suggest that inhibition of Cdk5 enhances the c-Maf-Il-10 axis and thus potentiates improvement of anti-inflammatory therapy.
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Quinasa 5 Dependiente de la Ciclina/genética , Endotoxemia/genética , Inflamación/genética , Interleucina-10/genética , Macrófagos/metabolismo , Proteínas Proto-Oncogénicas c-maf/genética , Animales , Células Cultivadas , Quimiocinas/genética , Quimiocinas/metabolismo , Quinasa 5 Dependiente de la Ciclina/metabolismo , Citocinas/genética , Citocinas/metabolismo , Endotoxemia/inducido químicamente , Endotoxemia/metabolismo , Regulación de la Expresión Génica , Inflamación/metabolismo , Interleucina-10/metabolismo , Lipopolisacáridos , Pulmón/metabolismo , Pulmón/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-maf/metabolismoRESUMEN
BACKGROUND: The oncogenic transcript factor c-Maf is stabilized by the deubiquitinase Otub1 and promotes myeloma cell proliferation and confers to chemoresistance. Inhibition of the Otub1/c-Maf axis is a promising therapeutic target, but there are no inhibitors reported on this specific axis. METHODS: A luciferase assay was applied to screen potential inhibitors of Otub1/c-Maf. Annexin V staining/flow cytometry was applied to evaluate cell apoptosis. Immunoprecipitation was applied to examine protein ubiquitination and interaction. Xenograft models in nude mice were used to evaluate anti-myeloma activity of AVT. RESULTS: Acevaltrate (AVT), isolated from Valeriana glechomifolia, was identified based on a bioactive screen against the Otub1/c-Maf/luciferase system. AVT disrupts the interaction of Otub1/c-Maf thus inhibiting Otub1 activity and leading to c-Maf polyubiquitination and subsequent degradation in proteasomes. Consistently, AVT inhibits c-Maf transcriptional activity and downregulates the expression of its target genes key for myeloma growth and survival. Moreover, AVT displays potent anti-myeloma activity by triggering myeloma cell apoptosis in vitro and impairing myeloma xenograft growth in vivo but presents no marked toxicity. CONCLUSIONS: The natural product AVT inhibits the Otub1/c-Maf axis and displays potent anti-myeloma activity. Given its great safety and efficacy, AVT could be further developed for MM treatment. Video Abstract.
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Antineoplásicos Fitogénicos/uso terapéutico , Cisteína Endopeptidasas/metabolismo , Inhibidores de Cisteína Proteinasa/uso terapéutico , Iridoides/uso terapéutico , Mieloma Múltiple/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-maf/antagonistas & inhibidores , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cisteína Endopeptidasas/genética , Inhibidores de Cisteína Proteinasa/farmacología , Femenino , Humanos , Iridoides/farmacología , Ratones Endogámicos BALB C , Ratones Desnudos , Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Proteínas Proto-Oncogénicas c-maf/genética , Proteínas Proto-Oncogénicas c-maf/metabolismoRESUMEN
BACKGROUND AND PURPOSE: Adiponectin (APN) is an adipokine secreted from adipocytes that binds to APN receptors AdipoR1 and AdipoR2 and exerts an anti-inflammatory response through mechanisms not fully understood. There is a need to develop small molecules that activate AdipoR1 and AdipoR2 and to be used to inhibit the inflammatory response in lipopolysaccharide (LPS)-induced endotoxemia and other inflammatory disorders. EXPERIMENTAL APPROACH: We designed 10 new structural analogues of an AdipoR agonist, AdipoRon (APR), and assessed their anti-inflammatory properties. Bone marrow-derived macrophages (BMMs) and peritoneal macrophages (PEMs) were isolated from mice. Levels of pro-inflammatory cytokines were measured by reverse transcription and real-time quantitative polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA) and microarray in LPS-induced endotoxemia mice and diet-induced obesity (DIO) mice in which systemic inflammation prevails. Western blotting, immunohistochemistry (IHC), siRNA interference and immunoprecipitation were used to detect signalling pathways. KEY RESULTS: A novel APN receptor agonist named adipo anti-inflammation agonist (AdipoAI) strongly suppresses inflammation in DIO and endotoxemia mice, as well as in cultured macrophages. We also found that AdipoAI attenuated the association of AdipoR1 and APPL1 via myeloid differentiation marker 88 (MyD88) signalling, thus inhibiting activation of nuclear factor kappa B (NF-κB), mitogen-activated protein kinase (MAPK) and c-Maf pathways and limiting the production of pro-inflammatory cytokines in LPS-induced macrophages. CONCLUSION AND IMPLICATIONS: AdipoAI is a promising alternative therapeutic approach to APN and APR to suppress inflammation in LPS-induced endotoxemia and other inflammatory disorders via distinct signalling pathways.
Asunto(s)
Adiponectina , Receptores de Adiponectina , Proteínas Adaptadoras Transductoras de Señales , Adiponectina/metabolismo , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Citocinas/metabolismo , Inflamación/tratamiento farmacológico , Lipopolisacáridos , Ratones , FN-kappa B/metabolismo , Receptores de Adiponectina/metabolismo , Receptores de Adiponectina/uso terapéuticoRESUMEN
The relationship between serum lipid profiles and related clinicopathologic features of IgA nephropathy (IgAN) and c-Maf-inducing protein (CMIP) gene polymorphisms is unclear. The present study was designed to examine the effect of CMIP single-nucleotide polymorphisms (SNPs) on dyslipidaemia and clinicopathologic features of IgAN. Clinical and pathological data from patients with IgAN diagnosed at the First Affiliated Hospital of Guangxi Medical University were collected. DNA was extracted from blood samples. CMIP rs2925979 and CMIP rs16955379 genotypes were determined by PCR and direct sequencing. Among 543 patients, 281 had dyslipidaemia (51.7%). Compared with the non-dyslipidaemia group, the dyslipidaemia group exhibited higher blood pressure, blood urea nitrogen, uric acid, and body mass index; higher prevalence of oedema, haematuria, tubular atrophy, and interstitial fibrosis; and lower albumin and estimated glomerular filtration rate. In the dyslipidaemia group, the frequency of C allele carriers was higher than that of non-C allele carriers for rs16955379. Multivariate linear regression analysis showed that total cholesterol, low-density lipoprotein and high-density lipoprotein were associated with rs16955379C allele carriers. Apolipoprotein B was associated with A allele carriers of rs2925979. Linkage disequilibrium was observed between rs16955379 and rs2925979, and rs2925979G-rs16955379T was the most common haplotype. The frequencies of the four CMIP SNP haplotypes differed between dyslipidaemia and non-dyslipidaemia groups in IgAN (P<0.05, for all above). Dyslipidaemia is a common complication in IgAN patients, and those with dyslipidaemia present poor clinicopathologic features. CMIP SNPs and their haplotypes are closely correlated with the occurrence of dyslipidaemia and clinicopathologic damage in IgAN patients.