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1.
Bioengineered ; 13(5): 11517-11529, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35510516

RESUMO

Astragaloside IV (AS-IV) is a bioactive saponin extracted from the Astragalus root and has been reported to exert a protective effect on diabetic nephropathy (DN). However, the underlying mechanism remains unclear. Herein, we found that AS-IV treatment alleviated DN symptoms in DN mice accompanied by reduced metabolic parameters (body weight, urine microalbumin and creatinine, creatinine clearance, and serum urea nitrogen and creatinine), pathological changes, and apoptosis. Epigenetic histone modifications are closely related to diabetes and its complications, including H3 lysine 4 monomethylation (H3K4me1, a promoter of gene transcription). A ChIP-seq assay was conducted to identify the genes regulated by H3K4me1 in DN mice after AS-IV treatment and followed by a Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis. The results showed that there were 16 common genes targeted by H3K4me1 in normal and AS-IV-treated DN mice, 1148 genes were targeted by H3K4me1 only in DN mice. From the 1148 genes, we screened mitogen-activating protein kinase kinase kinase kinase-3 (MAP4K3) for the verification of gene expression and functional study. The results showed that MAP4K3 was significantly increased in DN mice and high glucose (HG)-treated NRK-52E cells, which was reversed by AS-IV. MAP4K3 silencing reduced the apoptosis of NRK-52E cells under HG condition, as evidenced by decreased cleaved caspase 3 and Bax (pro-apoptotic factors), and increased Bcl-2 and Bcl-xl (anti-apoptotic factors). Collectively, AS-IV may downregulate MAP4K3 expression by regulating H3K4me1 binding and further reducing apoptosis, which may be one of the potential mechanisms that AS-IV plays a protective effect on DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Saponinas , Animais , Apoptose , Creatinina/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , Feminino , Lisina , Masculino , Camundongos , Mitógenos/farmacologia , Proteínas Quinases/farmacologia , Ratos Sprague-Dawley , Saponinas/farmacologia , Triterpenos
2.
Neoplasia ; 29: 100799, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35504112

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer worldwide and incidence rates are continuing to rise globally. Patients often present with locally advanced disease and a staggering 50% chance of relapse following treatment. Aberrant activation of adaptive response signaling pathways, such as the cAMP/PKA pathway, induce an array of genes associated with known cancer pathways that promote tumorigenesis and drug resistance. We identified the cAMP Regulated Transcription Coactivator 2 (CRTC2) to be overexpressed and constitutively activated in HNSCCs and this confers poor prognosis. CRTCs are regulated through their subcellular localization and we show that CRTC2 is exclusively nuclear in HPV(+) HNSCC, thus constitutively active, due to non-canonical Mitogen-Activated Kinase Kinase 1 (MEKK1)-mediated activation via a MEKK1-p38 signaling axis. Loss-of-function and pharmacologic inhibition experiments decreased CRTC2/CREB transcriptional activity by reducing nuclear CRTC2 via nuclear import inhibition and/or by eviction of CRTC2 from the nucleus. This shift in localization was associated with decreased proliferation, migration, and invasion. Our results suggest that small molecules that inhibit nuclear CRTC2 and p38 activity may provide therapeutic benefit to patients with HPV(+) HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Carcinogênese , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Humanos , Mitógenos , Recidiva Local de Neoplasia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fatores de Transcrição/genética
3.
PLoS Negl Trop Dis ; 16(5): e0010340, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35503786

RESUMO

BACKGROUND: Annual mass drug administrations (MDA) of ivermectin will strongly reduce Onchocerca volvulus microfilariae (mf) in the skin and in the onchocerciasis patients' eyes. Ivermectin treatment will also affect the expression of immunity in patients, such that activated immune defenses may help control and contribute to clearance of mf of O. volvulus. Longitudinal surveys are a prerequisite to determining the impact of ivermectin on the status of anti-parasite immunity, notably in risk zones where parasite transmission and active O. volvulus infections persist. METHODOLOGY/PRINCIPAL FINDINGS: Onchocerciasis patients were treated annually with ivermectin and their Onchocerca volvulus antigen (OvAg) specific IgG and cellular responses were investigated before and at 30 years post initial ivermectin treatment (30yPT). Repeated annual ivermectin treatments eliminated persisting O. volvulus microfilariae (mf) from the skin of patients and abrogated patent infections. The OvAg-specific IgG1 and IgG4 responses were diminished at 30yPT to the levels observed in endemic controls. Prior to starting ivermectin treatment, OvAg-induced cellular productions of IL-10, IFN-γ, CCL13, CCL17 and CCL18 were low in patients, and at 30yPT, cellular cytokine and chemokine responses increased to the levels observed in endemic controls. In contrast, mitogen(PHA)- induced IL-10, IFN-γ, CCL17 and CCL18 cellular production was diminished. This divergent response profile thus revealed increased parasite antigen-specific but reduced polyclonal cellular responsiveness in patients. The transmission of O. volvulus continued at the patients' location in the Mô river basin in central Togo 2018 and 2019 when 0.58% and 0.45%, respectively, of Simulium damnosum s.l. vector blackflies carried O. volvulus infections. CONCLUSIONS/SIGNIFICANCE: Repeated annual ivermectin treatment of onchocerciasis patients durably inhibited their patent O. volvulus infections despite ongoing low-level parasite transmission in the study area. Repeated MDA with ivermectin affects the expression of immunity in patients. O. volvulus parasite-specific antibody levels diminished to levels seen in infection-free endemic controls. With low antibody levels, antibody-dependent cellular cytotoxic responses against tissue-dwelling O. volvulus larvae will weaken. O. volvulus antigen inducible cytokine and chemokine production increased in treated mf-negative patients, while their innate responsiveness to mitogen declined. Such lower innate responsiveness in elderly patients could contribute to reduced adaptive immune responses to parasite infections and vaccines. On the other hand, increased specific cellular chemokine responses in mf-negative onchocerciasis patients could reflect effector cell activation against tissue invasive larval stages of O. volvulus. The annual Simulium damnosum s.l. biting rate observed in the Mô river basin was similar to levels prior to initiation of MDA with ivermectin, and the positive rtPCR results reported here confirm ongoing O. volvulus transmission.


Assuntos
Volvo Intestinal , Onchocerca volvulus , Oncocercose , Parasitos , Simuliidae , Idoso , Animais , Citocinas , Humanos , Imunoglobulina G , Interleucina-10 , Ivermectina/uso terapêutico , Microfilárias , Mitógenos/uso terapêutico , Onchocerca , Simuliidae/parasitologia , Togo/epidemiologia
4.
J Exp Clin Cancer Res ; 41(1): 139, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35414102

RESUMO

BACKGROUND: Glioblastoma multiforme (GBM) is an incurable tumor, with a median survival rate of only 14-15 months. Along with heterogeneity and unregulated growth, a central matter in dealing with GBMs is cell invasiveness. Thus, improving prognosis requires finding new agents to inhibit key multiple pathways, even simultaneously. A subset of GBM stem-like cells (GSCs) may account for tumorigenicity, representing, through their pathways, the proper cellular target in the therapeutics of glioblastomas. GSCs cells are routinely enriched and expanded due to continuous exposure to specific growth factors, which might alter some of their intrinsic characteristic and hide therapeutically relevant traits. METHODS: By removing exogenous growth factors stimulation, here we isolated and characterized a subset of GSCs with a "mitogen-independent" phenotype (I-GSCs) from patient's tumor specimens. Differential side-by-side comparative functional and molecular analyses were performed either in vitro or in vivo on these cells versus their classical growth factor (GF)-dependent counterpart (D-GSCs) as well as their tissue of origin. This was performed to pinpoint the inherent GSCs' critical regulators, with particular emphasis on those involved in spreading and tumorigenic potential. Transcriptomic fingerprints were pointed out by ANOVA with Benjamini-Hochberg False Discovery Rate (FDR) and association of copy number alterations or somatic mutations was determined by comparing each subgroup with a two-tailed Fisher's exact test. The combined effects of interacting in vitro and in vivo with two emerging GSCs' key regulators, such as Wnt5a and EphA2, were then predicted under in vivo experimental settings that are conducive to clinical applications. In vivo comparisons were carried out in mouse-human xenografts GBM model by a hierarchical linear model for repeated measurements and Dunnett's multiple comparison test with the distribution of survival compared by Kaplan-Meier method. RESULTS: Here, we assessed that a subset of GSCs from high-grade gliomas is self-sufficient in the activation of regulatory growth signaling. Furthermore, while constitutively present within the same GBM tissue, these GF-independent GSCs cells were endowed with a distinctive functional and molecular repertoire, defined by highly aggressive Wnt5aHigh/EphA2Low profile, as opposed to Wnt5aLow/EphA2High expression in sibling D-GSCs. Regardless of their GBM subtype of origin, I-GSCs, are endowed with a raised in vivo tumorigenic potential than matched D-GSCs, which were fast-growing ex-vivo but less lethal and invasive in vivo. Also, the malignant I-GSCs' transcriptomic fingerprint faithfully mirrored the original tumor, bringing into evidence key regulators of invasiveness, angiogenesis and immuno-modulators, which became candidates for glioma diagnostic/prognostic markers and therapeutic targets. Particularly, simultaneously counteracting the activity of the tissue invasive mediator Wnt5a and EphA2 tyrosine kinase receptor addictively hindered GSCs' tumorigenic and invasive ability, thus increasing survival. CONCLUSION: We show how the preservation of a mitogen-independent phenotype in GSCs plays a central role in determining the exacerbated tumorigenic and high mobility features distinctive of GBM. The exploitation of the I-GSCs' peculiar features shown here offers new ways to identify novel, GSCs-specific effectors, whose modulation can be used in order to identify novel, potential molecular therapeutic targets. Furthermore, we show how the combined use of PepA, the anti-Wnt5a drug, and of ephrinA1-Fc to can hinder GSCs' lethality in a clinically relevant xenogeneic in vivo model thus being conducive to perspective, novel combinatorial clinical application.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Mitógenos/metabolismo , Mitógenos/farmacologia , Mitógenos/uso terapêutico , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Proteína Wnt-5a/genética , Proteína Wnt-5a/metabolismo
5.
Proc Natl Acad Sci U S A ; 119(18): e2115567119, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35476510

RESUMO

SignificanceThe prevailing dogma is that renewed mitogenic signaling is essential to traverse G1 phase of the cell cycle after each division. B lymphocytes undergo multiple mitotic divisions, termed clonal expansion, to expand antigen-specific cells that mediate effective immunity. Here we demonstrate that B cells that have undergone one cell division continue to proliferate even in absence of further mitogenic signals. This mitogen-independent proliferation is accompanied by an altered G1 phase marked by transcriptomic and proteomic features of G2/M. Survivin, a G2/M-specific oncogene, is required in G1 to achieve mitogen-independent proliferation.


Assuntos
Mitógenos , Proteômica , Linfócitos B , Divisão Celular , Fase G1 , Peptídeos e Proteínas de Sinalização Intercelular , Survivina/genética
6.
Cytokine ; 153: 155840, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35276635

RESUMO

BACKGROUND: Human immunodeficiency virus-1 (HIV-1) infection causes loss and anergy of CD4+ and CD8+ T cells, leading to opportunistic infections, including tuberculosis (TB). QuantiFERON®-TB (QFT) is used as a diagnostic tool to detect TB, but it exhibits limited accuracy among subjects with low CD4+ T cell numbers, including HIV-1-infected individuals. The present study aimed to determine the effect of HIV-1 infection and patients' blood T cell numbers on cytokine production in response to mitogen (Mit) stimulation. METHODS: The number of CD4+ and CD8+ T cells in HIV-1-infected individuals was quantified. Levels of various cytokines in Mit-stimulated and un-stimulated (Nil) supernatants of QFT gold "in tube" were assessed using a MAGPIX System. The correlation between cytokine levels and CD4+/CD8+ T cell counts in response to Mit was analyzed. The cytokine levels were compared between HIV-1-infected and healthy subjects. RESULTS: HIV-1-infected individuals (110) and control subjects (27) were enrolled. Interferon (IFN)-γ, interleukin-1 receptor antagonist (IL-1RA), IL-6, IL-8, and regulated on activation, normal T cell expressed and secreted (RANTES) values in Mit-Nil tubes showed a significant correlation with CD4+ T cell counts, while IFN-γ, IL-6, and IFN-γ-induced protein 10 (IP-10) values in Mit-Nil tubes had significant correlation with CD8+ T cell counts. IL-1RA, IL-8, IP-10, platelet-derived growth factor (PDGF)-BB, and RANTES levels in Nil tubes were significantly higher in the HIV-1-infected group. IFN-γ, IL-2, IL-5, IL-6, IP-10, and macrophage inflammatory protein-1ß values in Mit-Nil tubes were significantly higher, and PDGF-BB and RANTES levels were significantly lower in the HIV-1-infected group. CONCLUSION: The functions of HIV-1-infected T cells and uninfected T cells, such as spontaneous and responsive cytokine production in response to Mit, were different. Our findings may be useful for developing new clinical tools for patients with low T cell counts. Additionally, the study provides new insights into the pathogenesis of HIV-1 infection.


Assuntos
Infecções por HIV , HIV-1 , Tuberculose , Células Sanguíneas/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Quimiocina CCL5 , Quimiocina CXCL10 , Citocinas , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Interleucina-6 , Interleucina-8 , Mitógenos
7.
Inflamm Res ; 71(3): 331-341, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35157090

RESUMO

OBJECTIVE AND DESIGN: Perturbations of peripheral T cell homeostasis and dysregulation of the immune response to SARS-CoV-2, especially in severely ill patients, were observed. The aim of this study was to analyze the cytokine producing ability of peripheral blood cells from severely ill COVID-19 patients upon non-specific in vitro stimulation with phytohemagglutinin (PHA). Possible associations of cytokine levels with patients' age and gender, glucocorticosteroid therapy, as well as the trend of the inflammatory process at the time of sampling (increased or decreased) were also analyzed. SUBJECTS AND METHODS: The study included 23 COVID-19 patients and 17 healthy control subjects. The concentrations of selected Th1/Th2/Th9/Th17/Th22 cytokines were determined using a multi-analyte flow assay kit. RESULTS: Our results showed that peripheral blood cells from severely ill COVID-19 patients had a much reduced ability to produce cytokines in comparison to healthy controls. When inflammation was raised, blood cells produced more IL-6 and IL-17, which led to increases of some Th17/Th1 and Th17/Th2 ratios, skewing towards the Th17 type of response. The methylprednisolone used in the treatment of patients with COVID-19 influences the production of several cytokines in dose dependent manner. CONCLUSION: Our results indicate that the stage of the inflammatory process at the time of sampling and the dose of the applied glucocorticosteroid therapy might influence cytokine producing ability upon non-specific stimulation of T cells in vitro.


Assuntos
COVID-19/sangue , Citocinas/sangue , SARS-CoV-2 , Adulto , Idoso , Anti-Inflamatórios/uso terapêutico , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , COVID-19/tratamento farmacológico , Células Cultivadas , Feminino , Glucocorticoides/uso terapêutico , Humanos , Masculino , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Mitógenos/farmacologia , Fito-Hemaglutininas/farmacologia
8.
Prostate ; 82(7): 816-825, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35226379

RESUMO

BACKGROUND: Prostate cancer (PC) is the most commonly diagnosed malignancy and the second leading cause of cancer-related deaths in males. The disease is initially treated with methods that inhibit androgen receptor (AR) signal transduction. Laboratory-based and clinical studies have identified alternative pathways that cause the failure of AR signal inhibition and consequent development of castration-resistant prostate cancer (CRPC). Glucocorticoid receptor (GR) signaling is activated in certain PC patients and promotes the emergence of CRPC, although by as yet incompletely understood mechanisms. We have previously demonstrated that ubiquitous ßarrestin1 (ßArr1) expression levels are linked to PC progression. Here, we consider the possibility that ßArr1 interacts with and activates GR in model CRPC cells. METHODS: Bioinformatic analysis of tumor xenograft and human PC datasets was used to correlate the expression of ßArr1 and GR. Western blot, immunohistochemistry and immunofluorescence microscopy, and subcellular fractionation were used to determine protein expression level and localization. Immunoprecipitation was applied to detect protein-protein interactions. RNA expression levels were determined using quantitative reverse transcription-polymerase chain reaction. Prostate sphere analysis was used to assess the rate of growth and invasion. The xenograft tumor implantation method was used to determine the tumor growth rate, local invasion, and metastasis. RESULTS: Elevated expression of ßArr1 positively correlated with increased GR expression and function in CRPC xenograft and in human PC patients. ßArr1 is expressed in the cell cytosol and nucleus, and it formed a complex with GR in the nucleus and not cytosol. Depletion of ßArr1 in AR-null CRPC cells inhibited GR function and CRPC growth and invasion in both in vitro and in vivo settings. CONCLUSIONS: ßArr1 binds GR that initiates mitogenic signaling cascades involved in the progression of PC to CRPC. The targeting of the ßArr1-GR axis may provide a new opportunity to better manage the CRPC disease.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Androgênios , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Mitógenos/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/patologia , Receptores Androgênicos/metabolismo , Receptores de Glucocorticoides/metabolismo , Transdução de Sinais , beta-Arrestina 1/genética , beta-Arrestina 1/metabolismo , beta-Arrestina 1/uso terapêutico
9.
Andrologia ; 54(3): e14342, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34872158

RESUMO

There are limited data on the influence of fructose rich diet on the male reproductive system. Kefir may have health beneficial effects, but its mechanism of action remains mostly unclear. Herein, we investigated the impact of dietary high fructose on tight junction proteins and mitogenic pathways in rat testis as well as their modulation by kefir supplementation. Twenty-two male Wistar rats (4 weeks old) were divided into the following three groups: Control; Fructose; Fructose + Kefir. Fructose was added to drinking water at concentration of 20% and administered to the rats for 15 weeks and kefir was supplemented by gavage once a day during final 6 weeks. Dietary fructose-induced testicular degeneration was associated with the downregulation of the blood-testis barrier proteins, claudin-11 and N-cadherin as well as SIRT1 expression in testicular tissue of rats. However, p38MAPK, p-p38MAPK and p-ERK1/2 levels were increased in testis of fructose-fed rats. Interestingly, JNK1 and p-JNK1 protein levels were decreased following this dietary intervention. Raf1, ERK1/2, and caspase 3 and TUNEL staining of the testis reveal the activation of apoptosis due to fructose intake. Kefir supplementation markedly promoted the expression of claudin-11, SIRT1, JNK1 and p-JNK1 but suppressed testicular mitogenic and apoptotic factors in fructose-fed rats.


Assuntos
Frutose , Kefir , Animais , Dieta , Suplementos Nutricionais , Frutose/efeitos adversos , Masculino , Mitógenos/farmacologia , Ratos , Ratos Wistar , Testículo
10.
Mol Biol Rep ; 49(2): 943-950, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34727288

RESUMO

BACKGROUND: The mitogenomic heteroplasmy is the presence of multiple haplotypes in the mitochondria, which could cause genetic diseases and is also associated with many critical biological functions. The topmouth culter (Culter alburnus Basilewsky, 1855) is one of the most important freshwater fish in the family of Cyprinidae in China. At present, there are no reports on the topmouth culter's mtDNA heteroplasmy and the existence of which is not known. METHODS AND RESULTS: This study aimed to analyze the mitogenomic heteroplasmy in the topmouth culter by the next-generation sequencing of the fins' total DNA. The results confirmed the existence of the heteroplasmy and indicated the presence of the extensive heteroplasmy in the topmouth culter's mitogenome. There were 38 heteroplasmic variations in the protein-coding genes from the three specimens, with 33 non-synonymous substitutions accounting for 86.84% and five synonymous substitutions accounting for 13.16%. Among them, the ND6 had the most heteroplasmic variations but only one synonymous substitution. After removing the putative nuclear mitochondrial DNA fragments, the ratio of primary haplotype in the three specimens was 43.89%, 74.72%, and 32.76%, respectively. The three specimens contained 21, 7, and 21 haplotypes of the mitogenomes, respectively. Due to the extensive heteroplasmy, we reconstructed the phylogenetic tree of the topmouth culter using the RY-coding method, which improved the performance of the phylogenetic tree to some extent. CONCLUSIONS: This study reported the mitogenomic heteroplasmy in the topmouth culter and enhanced the knowledge regarding the mitogenomic heteroplasmy in phylogenetic studies. As the topmouth culter is a commercial species, the mitogenomic heteroplasmy is crucial for the fisheries management of the topmouth culter.


Assuntos
Cyprinidae/genética , DNA Mitocondrial/genética , Heteroplasmia/genética , Animais , China , Cipriniformes/genética , Proteínas de Peixes/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mitógenos/genética , Filogenia
11.
EMBO Mol Med ; 14(1): e14511, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-34779136

RESUMO

In the course of our studies aiming to discover vascular bed-specific endothelial cell (EC) mitogens, we identified leukemia inhibitory factor (LIF) as a mitogen for bovine choroidal EC (BCE), although LIF has been mainly characterized as an EC growth inhibitor and an anti-angiogenic molecule. LIF stimulated growth of BCE while it inhibited, as previously reported, bovine aortic EC (BAE) growth. The JAK-STAT3 pathway mediated LIF actions in both BCE and BAE cells, but a caspase-independent proapoptotic signal mediated by cathepsins was triggered in BAE but not in BCE. LIF administration directly promoted activation of STAT3 and increased blood vessel density in mouse eyes. LIF also had protective effects on the choriocapillaris in a model of oxidative retinal injury. Analysis of available single-cell transcriptomic datasets shows strong expression of the specific LIF receptor in mouse and human choroidal EC. Our data suggest that LIF administration may be an innovative approach to prevent atrophy associated with AMD, through protection of the choriocapillaris.


Assuntos
Atrofia Geográfica , Fator Inibidor de Leucemia , Mitógenos , Animais , Corioide/irrigação sanguínea , Corioide/metabolismo , Células Endoteliais/metabolismo , Atrofia Geográfica/metabolismo , Janus Quinases/metabolismo , Fator Inibidor de Leucemia/metabolismo , Fator Inibidor de Leucemia/farmacologia , Camundongos , Mitógenos/metabolismo , Mitógenos/farmacologia , Fator de Transcrição STAT3/metabolismo
12.
J Cell Biol ; 220(12)2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34779857

RESUMO

Visceral adipose tissue shows remarkable plasticity, constantly replacing mature adipocytes from an inherent pool of adipocyte precursors. The number of precursors is set in the juvenile organism and remains constant in adult life. Which signals drive precursor pool expansion in juveniles and why they operate in visceral but not in subcutaneous white adipose tissue (WAT) are unclear. Using mouse models, we identified the insulin-sensitizing receptor SORLA as a molecular factor explaining the distinct proliferative capacity of visceral WAT. High levels of SORLA activity in precursors of juvenile visceral WAT prime these cells for nutritional stimuli provided through insulin, promoting mitotic expansion of the visceral precursor cell pool in overfed juvenile mice. SORLA activity is low in subcutaneous precursors, blunting their response to insulin and preventing diet-induced proliferation of this cell type. Our findings provide a molecular explanation for the unique proliferative properties of juvenile visceral WAT, and for the genetic association of SORLA with visceral obesity in humans.


Assuntos
Adipócitos/citologia , Insulina/farmacologia , Gordura Intra-Abdominal/metabolismo , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Receptores de LDL/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Índice de Massa Corporal , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Mitógenos/farmacologia , Células-Tronco/efeitos dos fármacos , Gordura Subcutânea/efeitos dos fármacos , Gordura Subcutânea/metabolismo , Adulto Jovem
13.
Food Chem Toxicol ; 158: 112662, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34743013

RESUMO

Bisphenol A (BPA) is a well-known endocrine-disrupting chemical related to the carcinogenesis of estrogen-responsive organs. Although human exposure to BPA mainly occurs via the oral route, its association with colon cancer has not been fully elucidated. We investigated the effects of BPA on the proliferation, migration, and tumor growth of colon cancer cells. BPA significantly promoted the proliferation of HT-29 human colon adenocarcinoma cells in a time- and dose-dependent manner. BPA also increased HT-29 cells migration. BPA increased the phosphorylation of extracellular signal-regulated kinase (ERK), and inhibition of the ERK pathway attenuated BPA-induced proliferation and migration. In addition, BPA reduced E-cadherin expression, a key factor impeding epithelial-to-mesenchymal transition, and increased 5-HT3 receptors expression, a major mitogenic factor. In xenograft models, tumor volume of the BPA-treated nude mice was 4.6 times that of the saline-treated group. Our findings provide primary evidence regarding the link between BPA and human colon cancer by demonstrating that BPA promotes the proliferation, migration, and tumor growth of colon cancer cells in both in vitro and in vivo models. In addition, we provided the mechanism of action of BPA, involved in the activation of the ERK pathway, the decrease in E-cadherin, and the increase in 5-HT3 receptors.


Assuntos
Compostos Benzidrílicos/efeitos adversos , Neoplasias do Colo , Disruptores Endócrinos/toxicidade , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fenóis/efeitos adversos , Receptores 5-HT3 de Serotonina/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Caderinas , Movimento Celular , Proliferação de Células , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Poluentes Ambientais/efeitos adversos , Transição Epitelial-Mesenquimal , Células HT29 , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitógenos , Fosforilação , Serotonina , Transdução de Sinais , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Mol Sci ; 22(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576152

RESUMO

Aryl hydrocarbon receptor (AHR) genomic pathway has been well-characterized in a number of respiratory diseases. In addition, the cytoplasmic AHR protein may act as an adaptor of E3 ubiquitin ligase. In this study, the physiological functions of AHR that regulate cell proliferation were explored using the CRISPR/Cas9 system. The doubling-time of the AHR-KO clones of A549 and BEAS-2B was observed to be prolonged. The attenuation of proliferation potential was strongly associated with either the induction of p27Kip1 or the impairment in mitogenic signal transduction driven by the epidermal growth factor (EGF) and EGF receptor (EGFR). We found that the leucine-rich repeats and immunoglobulin-like domains 1 (LRIG1), a repressor of EGFR, was induced in the absence of AHR in vitro and in vivo. The LRIG1 tends to degrade via a proteasome dependent manner by interacting with AHR in wild-type cells. Either LRIG1 or a disintegrin and metalloprotease 17 (ADAM17) were accumulated in AHR-defective cells, consequently accelerating the degradation of EGFR, and attenuating the response to mitogenic stimulation. We also affirmed low AHR but high LRIG1 levels in lung tissues of chronic obstructive pulmonary disease (COPD) patients. This might partially elucidate the sluggish tissue repairment and developing inflammation in COPD patients.


Assuntos
Receptores ErbB/metabolismo , Glicoproteínas de Membrana/metabolismo , Mitógenos/metabolismo , Proteólise , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais , Células A549 , Proteína ADAM17/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Clonais , Fator de Crescimento Epidérmico/farmacologia , Humanos , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteólise/efeitos dos fármacos , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Regulação para Cima/efeitos dos fármacos
15.
Virology ; 564: 1-12, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34560573

RESUMO

Many poxviruses produce proteins that are related to epidermal growth factor (EGF). Prior genome sequencing of ectromelia virus revealed a gene predicted to produce a protein with homology to EGF, which we refer to as ectromelia growth factor (ECGF). ECGF is truncated relative to vaccinia growth factor (VGF) because the former lacks a transmembrane domain. We show these proteins can experience differential N-linked glycosylation. Despite these differences, both proteins maintain the six conserved cysteine residues important for the function of EGF. Since ECGF has not been characterized, our objective was to determine if it can act as a growth factor. We added ECGF to cultured cells and found that the EGF receptor becomes activated, S-phase was induced, doubling time decreased, and in vitro wound healing occurred faster compared to untreated cells. In summary, we demonstrate that ECGF can act as a mitogen in a similar manner as VGF.


Assuntos
Vírus da Ectromelia/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/metabolismo , Mitógenos/metabolismo , Proteínas Virais/metabolismo , Animais , Divisão Celular , Linhagem Celular , Movimento Celular , Fator de Crescimento Epidérmico/química , Glicosilação , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Ligação Proteica , Fase S , Transdução de Sinais , Vírus Vaccinia/metabolismo , Proteínas Virais/química , Cicatrização
16.
Ecotoxicol Environ Saf ; 225: 112746, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34482064

RESUMO

Betulinic acid (BA), a pentacyclic triterpenoid, has been associated with several biological effects, such as antioxidant, anti-inflammatory and antiviral activities. Previous studies have demonstrated that BA has the ability to alleviate intestinal mucosal damage, however, the potential mechanism associated with the effect has not been reported. This study aimed to investigate the possible protective mechanism of BA against cyclophosphamide (CYP)-induced intestinal mucosal damage. Here, we found that BA pretreatment prevented intestinal mucosal barrier dysfuction from CYP-challenged mice by repairing the intestinal physical, chemical, and immune barriers. Moreover, BA treatment suppressed the CYP-induced oxidative stress by activating the nuclear factor erythroid 2 [NF-E2]-related factor (Nrf2) pathway blocked reactive oxygen species (ROS) accumulation. In addition, BA inhibited CYP-triggered intestinal inflammation through down-regulating the nuclear transcription factor kappa B (NF-κB)/mitogen-activating protein kinase (MAPK) pathways. Furthermore, BA pretreatment reduced intestinal apoptosis by blocking ROS-activated mitochondrial apoptotic pathway. Overall, the current study demonstrated the protective effect of BA against CYP-caused intestinal mucosal damage by regulating the Nrf2 and NF-κB/MAPK signalling pathways, which may provide new therapeutic targets to attenuate intestinal impairment and maintain intestinal health.


Assuntos
Fator 2 Relacionado a NF-E2 , Triterpenos , Animais , Ciclofosfamida/toxicidade , Mucosa Intestinal/metabolismo , Camundongos , Mitógenos/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Triterpenos Pentacíclicos , Triterpenos/metabolismo , Triterpenos/farmacologia
17.
Physiol Rep ; 9(17): e15010, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34496147

RESUMO

This study characterized the effect of moderate- or vigorous-intensity exercise on leukocyte counts, using fingertip sampling, and mitogen-stimulated oxidative burst, measured in whole blood with a point-of-care test. In a randomized crossover design, 13 healthy adults (mean ± SD age: 22 ± 2 years; seven male, six female) cycled for 30-min, once at 52 ± 5% V ˙ O2peak and on another occasion at 74 ± 9% V ˙ O2peak . Blood was sampled at baseline, immediately post-exercise, and 15- and 60-min post-exercise. The leukocyte differential and mitogen-stimulated Reactive Oxygen Species (ROS) production were assessed. Lymphocytes increased immediately post-exercise and decreased below pre-exercise levels 15- and 60-min later. Lymphocyte mobilization immediately post-exercise was 59 ± 36% greater with vigorous- compared to moderate-intensity exercise (p < 0.01). Neutrophils increased immediately after exercise (38 ± 19%, p < 0.01) remaining elevated 60-min later (50 ± 34%, p < 0.01; averaged across intensities) and did not differ between intensities (p = 0.259). Mitogen-stimulated ROS production was amplified immediately (+32 ± 37%, p < 0.01) and 60-min post-exercise (+56 ± 57%, p < 0.01; averaged across intensities) compared to rest and did not differ with intensity (p = 0.739). Exercise-induced amplification of ROS production was abolished when correcting for neutrophil, monocyte and platelet counts and correlated most strongly with neutrophil mobilization immediately (r = 0.709, p < 0.01) and 60-min after vigorous exercise (r = 0.687, p < 0.01). Leukocyte kinetics can be assessed using fingertip blood sampling in exercise settings. Exercise-induced amplification of oxidative burst is detectable with a point-of-care test, but results are strongly influenced by neutrophil counts, which may not be routinely quantified.


Assuntos
Teste de Esforço/métodos , Exercício Físico/fisiologia , Leucócitos/metabolismo , Neutrófilos/metabolismo , Explosão Respiratória/fisiologia , Estudos Cross-Over , Feminino , Humanos , Masculino , Mitógenos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Adulto Jovem
18.
Int J Hematol ; 114(6): 682-690, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34420193

RESUMO

Infection is one of the major causes of death in hematopoietic stem cell transplantation (HSCT) survivors. Precise assessments of immune function after HSCT will be critical in establishing appropriate treatment and prophylaxis, such as re-vaccination. Although several surrogate markers for prediction of clinical outcomes after HSCT have been proposed, definitive markers of immune reconstitution and data on those markers in long-term survivors are lacking. In this study, cellular response to mitogens was assessed and clinical features associated with a poor response to mitogens were investigated in long-term allogeneic HSCT survivors. Age at transplantation and age at the time of mitogen stimulation test were each identified as significant risk factors for poor response to phytohemagglutinin and concanavalin A, respectively (P < 0.001 each). However, time elapsed since transplantation was not found to be correlated with responsiveness to mitogens in this study. Prospective, in-depth studies on immune reconstitution are needed to establish appropriate prophylaxis against infections after HSCT and a schedule for re-vaccination.


Assuntos
Imunidade Celular , Mitógenos/imunologia , Doença Enxerto-Hospedeiro/diagnóstico , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas , Humanos , Contagem de Leucócitos , Ativação Linfocitária/imunologia , Estudos Prospectivos , Índice de Gravidade de Doença , Sobreviventes , Imunologia de Transplantes , Transplante Homólogo
19.
J Pharmacol Exp Ther ; 379(2): 125-133, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34373354

RESUMO

The pharmaceutical industry and clinical trials have been revolutionized mesenchymal stem cell-based therapeutics. However, the pharmacokinetics of transplanted cells has been little characterized in their target tissues under healthy or disease condition. A quantitative polymerase chain reaction analytical method with matrix effect was developed to track the biodistribution of human mesenchymal stem cells in normal mice and those with Concanavalin A (Con A)-induced liver injury. Mesenchymal stem/stromal cell (MSC) disposition in blood and different organs were compared, and relevant pharmacokinetic parameters were calculated. Human MSCs (hMSCs) and mouse MSCs (mMSCs) displayed a very similar pharmacokinetic profile in all tested doses: about 95% of the detected hMSCs accumulated in the lung and 3% in the liver, and almost negligible cells were detected in other tissues. A significant double peak of hMSC concentration emerged in the lung within 1-2 hours after intravenous injection, as with mMSCs. Prazosin, a vasodilator, could eliminate the second peak in the lung and increase its Cmax and area under the concentration-time curve (AUC) by 10% in the first 2 hours. The injury caused by Con A was significantly reduced by hMSCs, and the Cmax and AUC0-8 (AUC from time 0 to 8 hours) of cells in the injured liver decreased by 54 and 50%, respectively. The Cmax and AUC would be improved with the alleviation of congestion through the administration of heparin. The study provides a novel insight into the pharmacokinetics of exogenous MSCs in normal and Con A-induced liver injury mice, which provides a framework for optimizing cell transplantation. SIGNIFICANCE STATEMENT: Mesenchymal stem/stromal cells (MSCs) are known for their potential as regenerative therapies in treating several diseases, but an insufficient understanding of the pharmacokinetics of MSCs restricts their future application. The current study was the first to elucidate the pharmacokinetics and possible factors, including dosage, species, and derived sources, in a systematic way. The study further revealed that Concanavalin A-induced liver injury significantly prevented cells from entering the injury site, which could be reversed by the diminished congestion achieved by heparin.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/terapia , Concanavalina A/toxicidade , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Mitógenos/toxicidade , Animais , Células Cultivadas , Doença Hepática Induzida por Substâncias e Drogas/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL
20.
Cell Rep ; 36(4): 109436, 2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34320337

RESUMO

Contact inhibition of cell proliferation regulates tissue size and prevents uncontrolled cell expansion. When cell density increases, contact inhibition can force proliferating cells into quiescence. Here we show that the variable memory of local cell density experienced by a mother cell controls the levels of the cyclin-dependent kinase (CDK) activator cyclin D1 and inhibitor p27 in newborn daughters, which direct cells to proliferation or quiescence. Much of this regulation can be explained by rapid suppression of ERK activity by high cell density in mothers, which leads to lower cyclin D1 and higher p27 levels in daughters. Strikingly, cell density and mitogen signals compete by shifting the ratio of cyclin D1/p27 levels below or above a single sharp threshold that controls the proliferation decision. Thus, the history of competing cell density and mitogen signals experienced by mothers is funneled into a precise activator-inhibitor balance that decides the fate of daughter cells.


Assuntos
Ciclo Celular/genética , Contagem de Células , Ciclina D1/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Feminino , Humanos , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mitógenos/metabolismo , Modelos Biológicos , Fosforilação , Proteína do Retinoblastoma/metabolismo
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