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1.
Circ Res ; 131(6): 476-491, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35968712

RESUMO

BACKGROUND: Experimental evidence suggests a key role of SIRT1 (silent information regulator 1) in age- and metabolic-related vascular dysfunction. Whether these effects hold true in the human microvasculature is unknown. We aimed to investigate the SIRT1 role in very early stages of age- and obesity-related microvascular dysfunction in humans. METHODS: Ninety-five subjects undergoing elective laparoscopic surgery were recruited and stratified based on their body mass index status (above or below 30 kg/m2) and age (above or below 40 years) in 4 groups: Young Nonobese, Young Obese, Old Nonobese, and Old Obese. We measured small resistance arteries' endothelial function by pressurized micromyography before and after incubation with a SIRT1 agonist (SRT1720) and a mitochondria reactive oxygen species (mtROS) scavenger (MitoTEMPO). We assessed vascular levels of mtROS and nitric oxide availability by confocal microscopy and vascular gene expression of SIRT1 and mitochondrial proteins by qPCR. Chromatin immunoprecipitation assay was employed to investigate SIRT1-dependent epigenetic regulation of mitochondrial proteins. RESULTS: Compared with Young Nonobese, obese and older patients showed lower vascular expression of SIRT1 and antioxidant proteins (FOXO3 [forkhead box protein O3] and SOD2) and higher expression of pro-oxidant and aging mitochondria proteins p66Shc and Arginase II. Old Obese, Young Obese and Old Nonobese groups endothelial dysfunction was rescued by SRT1720. The restoration was comparable to the one obtained with mitoTEMPO. These effects were explained by SIRT1-dependent chromatin changes leading to reduced p66Shc expression and upregulation of proteins involved in mitochondria respiratory chain. CONCLUSIONS: SIRT1 is a novel central modulator of the earliest microvascular damage induced by age and obesity. Through a complex epigenetic control mainly involving p66Shc and Arginase II, it influences mtROS levels, NO availability, and the expression of proteins of the mitochondria respiratory chain. Therapeutic modulation of SIRT1 restores obesity- and age-related endothelial dysfunction. Early targeting of SIRT1 might represent a crucial strategy to prevent age- and obesity-related microvascular dysfunction.


Assuntos
Arginase , Obesidade , Sirtuína 1 , Doenças Vasculares , Adulto , Arginase/metabolismo , Epigênese Genética , Humanos , Proteínas Mitocondriais/metabolismo , Óxido Nítrico/metabolismo , Obesidade/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo , Doenças Vasculares/etiologia
2.
Rev Med Virol ; 33(4): e2452, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37119022

RESUMO

Fibroblast growth factors (FGFs) are a family of proteins that play a crucial role in the development and maintenance of various tissues in the body. There are three function-al groups of FGFs: canonical FGFs (cFGFs), intracellularly retained FGFs, and metabolic (also called endocrine) FGFs. cFGFs are secreted and act in an autocrine/paracrine fashion to regulate differentiation during foetal development, as well as tissue repair in adults. Recent studies have also begun to unravel the role of cFGFs during viral infections, suggesting that FGF-2 and other canonical FGFs may have an important virus-specific role, also by the regulation of the immune response. Because dysregulation in the FGF pathways is pivotal in cancer development, FGFs are the target of many anticancer drugs. These drugs may be repurposed to treat viral infection, since dysregulation of FGF signalling has been implicated in the pathogenesis of viral infections, such as hepatitis C. Overall, the role of cFGFs during viral infection is an underrepresented area of current research. This review focuses on overviewing the effects of canonical FGFs during infection by different viruses. Many studies highlight that the effects of FGFs during viral infection may be complex and context-dependent. While there is evidence to suggest that FGFs may have a beneficial impact on the immune response and tissue repair during viral infection, further studies are needed to fully understand the mechanisms underlying these effects and to determine in what cases FGFs could be targeted as a therapeutic approach for viral infection.


Assuntos
Antineoplásicos , Neoplasias , Viroses , Humanos , Fatores de Crescimento de Fibroblastos/metabolismo , Neoplasias/metabolismo
3.
J Hepatol ; 79(5): 1085-1095, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37348789

RESUMO

BACKGROUND & AIMS: Chronic liver disease (CLD) is associated with increased cardiovascular disease (CVD) risk. We investigated whether early signs of liver disease (measured by iron-corrected T1-mapping [cT1]) were associated with an increased risk of major CVD events. METHODS: Liver disease activity (cT1) and fat (proton density fat fraction [PDFF]) were measured using LiverMultiScan® between January 2016 and February 2020 in the UK Biobank imaging sub-study. Using multivariable Cox regression, we explored associations between liver cT1 (MRI) and primary CVD (coronary artery disease, atrial fibrillation [AF], embolism/vascular events, heart failure [HF] and stroke), and CVD hospitalisation and all-cause mortality. Liver blood biomarkers, general metabolism biomarkers, and demographics were also included. Subgroup analysis was conducted in those without metabolic syndrome (defined as at least three of: a large waist, high triglycerides, low high-density lipoprotein cholesterol, increased systolic blood pressure, or elevated haemoglobin A1c). RESULTS: A total of 33,616 participants (mean age 65 years, mean BMI 26 kg/m2, mean haemoglobin A1c 35 mmol/mol) had complete MRI liver data with linked clinical outcomes (median time to major CVD event onset: 1.4 years [range: 0.002-5.1]; follow-up: 2.5 years [range: 1.1-5.2]). Liver disease activity (cT1), but not liver fat (PDFF), was associated with higher risk of any major CVD event (hazard ratio 1.14; 95% CI 1.03-1.26; p = 0.008), AF (1.30; 1.12-1.51; p <0.001); HF (1.30; 1.09-1.56; p= 0.004); CVD hospitalisation (1.27; 1.18-1.37; p <0.001) and all-cause mortality (1.19; 1.02-1.38; p = 0.026). FIB-4 index was associated with HF (1.06; 1.01-1.10; p = 0.007). Risk of CVD hospitalisation was independently associated with cT1 in individuals without metabolic syndrome (1.26; 1.13-1.4; p <0.001). CONCLUSION: Liver disease activity, by cT1, was independently associated with a higher risk of incident CVD and all-cause mortality, independent of pre-existing metabolic syndrome, liver fibrosis or fat. IMPACT AND IMPLICATIONS: Chronic liver disease (CLD) is associated with a twofold greater incidence of cardiovascular disease. Our work shows that early liver disease on iron-corrected T1 mapping was associated with a higher risk of major cardiovascular disease (14%), cardiovascular disease hospitalisation (27%) and all-cause mortality (19%). These findings highlight the prognostic relevance of a comprehensive evaluation of liver health in populations at risk of CVD and/or CLD, even in the absence of clinical manifestations or metabolic syndrome, when there is an opportunity to modify/address risk factors and prevent disease progression. As such, they are relevant to patients, carers, clinicians, and policymakers.


Assuntos
Doenças Cardiovasculares , Doenças do Sistema Digestório , Hepatopatias , Síndrome Metabólica , Humanos , Idoso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Bancos de Espécimes Biológicos , Hemoglobinas Glicadas , Biobanco do Reino Unido , Fatores de Risco , Hepatopatias/complicações , Biomarcadores , Ferro
4.
Int J Mol Sci ; 24(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37834255

RESUMO

The human T-cell leukemia virus type 1 (HTLV-1) is the only known human oncogenic retrovirus. HTLV-1 can cause a type of cancer called adult T-cell leukemia/lymphoma (ATL). The virus is transmitted through the body fluids of infected individuals, primarily breast milk, blood, and semen. At least 5-10 million people in the world are infected with HTLV-1. In addition to ATL, HTLV-1 infection can also cause HTLV-I-associated myelopathy (HAM/TSP). ATL is characterized by a low viral expression and poor prognosis. The oncogenic mechanism triggered by HTLV-1 is extremely complex and the molecular pathways are not fully understood. However, viral regulatory proteins Tax and HTLV-1 bZIP factor (HBZ) have been shown to play key roles in the transformation of HTLV-1-infected T cells. Moreover, several studies have shown that the final fate of HTLV-1-infected transformed Tcell clones is the result of a complex interplay of HTLV-1 oncogenic protein expression with cellular transcription factors that subvert the cell cycle and disrupt regulated cell death, thereby exerting their transforming effects. This review provides updated information on the mechanisms underlying the transforming action of HTLV-1 and highlights potential therapeutic targets to combat ATL.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto , Adulto , Feminino , Humanos , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Proteínas dos Retroviridae/genética , Proteínas dos Retroviridae/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Carcinogênese , Transformação Celular Neoplásica/genética
5.
Int J Mol Sci ; 24(24)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38139245

RESUMO

Cisplatin is a chemotherapeutic drug for the treatment of several solid tumors, whose use is limited by its nephrotoxicity, neurotoxicity, ototoxicity, and development of resistance. The toxicity is caused by DNA cross-linking, increase in reactive oxygen species and/or depletion of cell antioxidant defenses. The aim of the work was to study the effect of antioxidant compounds (Lisosan G, Taurisolo®) or hydrogen sulfide (H2S)-releasing compounds (erucin) in the auditory HEI-OC1 cell line treated with cisplatin. Cell viability was determined using the MTT assay. Caspase and sphingomyelinase activities were measured by fluorometric and colorimetric methods, respectively. Expression of transcription factors, apoptosis hallmarks and genes codifying for antioxidant response proteins were measured by Western blot and/or RT-qPCR. Lisosan G, Taurisolo® and erucin did not show protective effects. Sodium hydrosulfide (NaHS), a donor of H2S, increased the viability of cisplatin-treated cells and the transcription of heme oxygenase 1, superoxide dismutase 2, NAD(P)H quinone dehydrogenase type 1 and the catalytic subunit of glutamate-cysteine ligase and decreased reactive oxygen species (ROS), the Bax/Bcl2 ratio, caspase-3, caspase-8 and acid sphingomyelinase activity. Therefore, NaHS might counteract the cytotoxic effect of cisplatin by increasing the antioxidant response and by reducing ROS levels and caspase and acid sphingomyelinase activity.


Assuntos
Antineoplásicos , Cisplatino , Cisplatino/farmacologia , Cisplatino/metabolismo , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Células Ciliadas Auditivas/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo , Apoptose , Caspases/metabolismo , Suplementos Nutricionais , Sobrevivência Celular
6.
J Virol ; 95(23): e0135821, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34549986

RESUMO

Gene editing may be used to excise the human immunodeficiency virus type 1 (HIV-1) provirus from the host cell genome, possibly eradicating the infection. Here, using cells acutely or latently infected by HIV-1 and treated with long terminal repeat (LTR)-targeting CRISPR/Cas9, we show that the excised HIV-1 provirus persists for a few weeks and may rearrange in circular molecules. Although circular proviral DNA is naturally formed during HIV-1 replication, we observed that gene editing might increase proviral DNA circles with restored LTRs. These extrachromosomal elements were recovered and probed for residual activity through their transfection in uninfected cells. We discovered that they can be transcriptionally active in the presence of Tat and Rev. Although confirming that gene editing is a powerful tool to eradicate HIV-1 infection, this work highlights that, to achieve this goal, the LTRs must be cleaved in several pieces to avoid residual activity and minimize the risk of reintegration in the context of genomic instability, possibly caused by the off-target activity of Cas9. IMPORTANCE The excision of HIV-1 provirus from the host cell genome has proven feasible in vitro and, to some extent, in vivo. Among the different approaches, CRISPR/Cas9 is the most promising tool for gene editing. The present study underlines the remarkable effectiveness of CRISPR/Cas9 in removing the HIV-1 provirus from infected cells and investigates the fate of the excised HIV-1 genome. This study demonstrates that the free provirus may persist in the cell after editing and in appropriate circumstances may reactivate. As an episome, it might be transcriptionally active, especially in the presence of Tat and Rev. The persistence of the HIV-1 episome was strongly decreased by gene editing with multiple targets. Although gene editing has the potential to eradicate HIV-1 infection, this work highlights a potential issue that warrants further investigation.


Assuntos
Sistemas CRISPR-Cas , DNA Circular , HIV-1/genética , Provírus/genética , Sequências Repetidas Terminais , Proteína 9 Associada à CRISPR , Edição de Genes , Regulação Viral da Expressão Gênica , Terapia Genética , Células HEK293 , Infecções por HIV/virologia , Humanos , RNA Guia de Cinetoplastídeos/genética
7.
J Enzyme Inhib Med Chem ; 37(1): 2223-2240, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35979600

RESUMO

Introduction: Colchicine-binding site inhibitors are some of the most interesting ligands belonging to the wider family of microtubule-destabilising agents.Results: A novel series of 4'-fluoro-substituted ligands (5-13) was synthesised. The antiproliferative activity assays resulted in nM values for the new benzotriazole-acrylonitrile derivatives. Compound 5, the hit compound, showed an evident blockade of HeLa cell cycle in the G2-M phase, but also a pro-apoptotic potential, and an increase of early and late apoptotic cells in HeLa and MCF-7 cell cycle analysis. Confocal microscopy analysis showed a segmented shape and a collapse of the cytoskeleton, as well as a consistent cell shrinkage after administration of 5 at 100 nM. Derivative 5 was also proved to compete with colchicine at colchicine-binding site, lowering its activity against tubulin polymerisation. In addition, co-administration of 5 and doxorubicin in drug-resistant A375 melanoma cell line highlighted a synergic potential in terms of inhibition of cell viability.Discussion: The 4'-fluoro substitution of benzotriazole-acrylonitrile scaffold brought us a step forward in the optimisation process to obtain compound 5 as promising MDA antiproliferative agent at nanomolar concentration.


Assuntos
Acrilonitrila , Antineoplásicos , Acrilonitrila/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células , Colchicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Ligantes , Microtúbulos/metabolismo , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Triazóis , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina
8.
New Microbiol ; 44(4): 191-204, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34942015

RESUMO

Life implies adaptation. This is one of the fundamental principles that has permitted most living species to survive through ages in an ever-changing environment. Spontaneously occurring events have shaped also virus populations and their fitness. Thanks to their plasticity, viruses have thrived in extremely dissimilar conditions. Unsurprisingly, SARS-CoV-2, the etiological agent of COVID-19, is no exception. Thanks to an unprecedented rate of molecular tracing and sequence scrutiny, the virus was followed in all its changes and shown to evolve in such a way as to possibly determine subsequent waves of infection after the first global and massive outbreak. This review illustrates the major modifications occurred to the virus since its discovery. We describe the potential advantages that these changes conveyed as regards SARS-CoV-2 transmissibility, resistance to host innate and adaptive barriers and molecular diagnosis.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Glicoproteína da Espícula de Coronavírus
9.
Int J Mol Sci ; 22(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34884442

RESUMO

Proprotein convertase subtilisin kexin 9 (PCSK9) increases LDL cholesterol (C) concentration by accelerating the hepatic degradation of the LDL receptor (R) thus promoting atherogenesis. The molecule, however, also exerts proinflammatory effects independent of circulating LDL-C by enhancing local cytokine production and activation of NFkB, a process that might involve Toll-like receptor 4 (TLR4), a crucial component of the innate immunity system. Tissue factor (TF), a glycoprotein which plays an essential role in coagulation and inflammation, is rapidly induced by circulating monocytes stimulated by proinflammatory agents through NFkB-dependent mechanisms. The aims of our study were (1) to assess whether PCSK9 may induce monocytic TF expression and (2) to evaluate whether the TLR4/NFkB signaling pathway may contribute to that effect. Experiments were carried out in peripheral blood mononuclear cells (PBMCs), THP-1 cells, and HEK293 cells transfected with plasmids encoding the human TLR4 complex. PCSK9 increased procoagulant activity (PCA), mRNA and TF protein expression in both PBMCs and THP-1 cultures. Pre-treatment with inhibitors of TLR4/NFkB signaling such as LPS-RS, CLI-095, and BAY 11-7082, downregulated PCSK9-induced TF expression. A similar effect was obtained by incubating cell cultures with anti-PCSK9 human monoclonal antibody. In TLR4-HEK293 cells, PCSK9 activated the TLR4/NFkB signaling pathway to an extent comparable to LPS, the specific agonist of TLR4s and quantitative confocal microscopy documented the colocalization of PCSK9 and TLR4s. In conclusion, PCSK9 induces TF expression through activation of TLR4/NFkB signaling.


Assuntos
Monócitos/citologia , Pró-Proteína Convertase 9/metabolismo , Tromboplastina/genética , Tromboplastina/metabolismo , Receptor 4 Toll-Like/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipopolissacarídeos/farmacologia , Microscopia Confocal , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Nitrilas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Sulfonas/farmacologia , Células THP-1 , Receptor 4 Toll-Like/metabolismo , Transfecção , Regulação para Cima/efeitos dos fármacos
10.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806766

RESUMO

Cutaneous melanoma is often resistant to therapy due to its high plasticity, as well as its ability to metabolise chemotherapeutic drugs. Sphingolipid signalling plays a pivotal role in its progression and metastasis. One of the ways melanoma alters sphingolipid rheostat is via over-expression of lysosomal acid ceramidase (AC), which catalyses the hydrolysis of pro-apoptotic long-chain ceramides into sphingosine and fatty acid. In this report, we examine the role of acid ceramidase in maintaining cellular homeostasis through the regulation of autophagy and mitochondrial activity in melanoma cell lines. We show that under baseline conditions, wild-type melanoma cells had 3-fold higher levels of the autophagy marker, microtubule-associated proteins 1A/1B light chain 3B (LC3 II), compared to AC-null cells. This difference was further magnified after cell starvation. Moreover, we noticed autophagy impairment in A375 AC-null cells, possibly due to local accumulation of non-metabolized ceramides. Nonetheless, we observed that AC-null cells exhibited a significant increase in mitochondrial membrane potential compared to control cells. Consistent with this observation, we found that, after total starvation, ~30% of AC-null cells undergo apoptosis compared to ~6% of wild-type cells. As expected, AC transfection restored viability in A375 AC-null cells. Together, these findings suggest that AC-null melanoma cells change and adapt their metabolism to survive in the absence of AC, although in a way that does not allow them to cope with the stress of nutrient deprivation.


Assuntos
Ceramidase Ácida/genética , Autofagia/genética , Melanoma/genética , Melanoma/metabolismo , Mitocôndrias/genética , Ceramidase Ácida/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Imunofluorescência , Expressão Gênica , Humanos , Melanoma/patologia , Potencial da Membrana Mitocondrial , Fator de Transcrição Associado à Microftalmia/genética , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
11.
Int J Mol Sci ; 20(14)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336922

RESUMO

Melanoma is a malignant tumor deriving from neoplastic transformation of melanocytes. The incidence of melanoma has increased dramatically over the last 50 years. It accounts for most cases of skin cancer deaths. Early diagnosis leads to remission in 90% of cases of melanoma; conversely, for melanoma at more advanced stages, prognosis becomes more unfavorable also because dvanced melanoma is often resistant to pharmacological and radiological therapies due to genetic plasticity, presence of cancer stem cells that regenerate the tumor, and efficient elimination of drugs. This review illustrates the role of autophagy in tumor progression and resistance to therapy, focusing on molecular targets for future drugs.


Assuntos
Autofagia , Transformação Celular Neoplásica/metabolismo , Ceramidas/metabolismo , Suscetibilidade a Doenças , Melanoma/metabolismo , Transdução de Sinais , Esfingolipídeos/metabolismo , Ceramidase Ácida/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Biomarcadores Tumorais , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metabolismo dos Lipídeos , Melanoma/etiologia , Melanoma/patologia , Melanoma/terapia , Transdução de Sinais/efeitos dos fármacos
13.
J Med Genet ; 53(4): 242-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26729821

RESUMO

BACKGROUND: Primary ciliary dyskinesia (PCD) is a rare autosomal recessive genetic disorder characterised by dysfunction of motile cilia. Ciliary dysmotility causes poor mucociliary clearance and leads to impairment of pulmonary function and severe respiratory infections. PCD has no specific therapy. With the aim to permanently restore gene function and normalise ciliary motility, we used gene editing to replace mutated with wild-type sequence in defective cells. METHODS: The target gene was dynein heavy chain 11 (DNAH11), an essential component of ciliary structure. Airway ciliated cells were collected from two patients with PCD with DNAH11 nonsense mutations and altered ciliary beating and pattern. Repair of the genetic defect was performed ex vivo by site-specific recombination using transcription activator-like effector nucleases (TALENs). RESULTS: In an epithelial cell line engineered to contain the DNAH11 target site, TALENs cleaved over 80% of the mutated DNAH11 sequence and replaced the mutated sequence with wild-type sequence in about 50% of cells. In airway ciliated cells of patients with PCD, site-specific recombination and normalisation of ciliary beating and pattern occurred in 33% and 29% of cells, respectively. CONCLUSION: This study demonstrates that gene editing can rescue ciliary beating ex vivo, opening up new avenues for treating PCD.


Assuntos
Dineínas do Axonema/genética , Edição de Genes , Terapia Genética , Síndrome de Kartagener/terapia , Adolescente , Linhagem Celular , Movimento Celular/genética , Cílios/metabolismo , Cílios/patologia , Células Epiteliais/patologia , Genótipo , Humanos , Síndrome de Kartagener/genética , Síndrome de Kartagener/patologia , Lentivirus/genética , Masculino , Fenótipo , Gêmeos
14.
Biochem Pharmacol ; 219: 115952, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38036189

RESUMO

The aim of our study is to investigate in vitro and in vivo MC4R as a novel target in melanoma using the selective antagonist ML00253764 (ML) alone and in combination with vemurafenib, a B-rafV600E inhibitor. The human melanoma B-raf mutated A-2058 and WM 266-4 cell lines were used. An MC4R null A-2058 cell line was generated using a CRISPR/Cas9 system. MC4R protein expression was analysed by western blotting, immunohistochemistry, and immunofluorescence. Proliferation and apoptotic assays were performed with ML00253764, whereas the synergism with vemurafenib was evaluated by the combination index (CI) and Loewe methods. ERK1/2 phosphorylation and BCL-XL expression were quantified by western blot. In vivo experiments were performed in Athymic Nude-Foxn1nu male mice, injecting subcutaneously melanoma cells, and treating animals with ML, vemurafenib and their concomitant combination. Comet and cytome assays were performed. Our results show that human melanoma cell lines A-2058 and WM 266-4, and melanoma human tissue, express functional MC4R receptors on their surface. MC4R receptors on melanoma cells can be inhibited by the selective antagonist ML, causing antiproliferative and proapoptotic activity through the inhibition of phosphorylation of ERK1/2 and a reduction of BCL-XL. The concomitant combination of vemurafenib and ML caused a synergistic effect on melanoma cells in vitro and inhibited in vivo tumor growth in a preclinical model, without causing mouse weight loss or genotoxicity. Our original research contributes to the landscape of pharmacological treatments for melanoma, providing MC4R antagonists as drugs that can be added to established therapies.


Assuntos
Melanoma , Masculino , Humanos , Animais , Camundongos , Vemurafenib/farmacologia , Melanoma/metabolismo , Receptor Tipo 4 de Melanocortina , Proliferação de Células , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Mutação
15.
J Virol ; 86(12): 6563-74, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22491465

RESUMO

Genital herpes is caused by herpes simplex virus 1 (HSV-1) and HSV-2, and its incidence is constantly increasing in the human population. Regardless of the clinical manifestation, HSV-1 and HSV-2 infections are highly transmissible to sexual partners and enhance susceptibility to other sexually transmitted infections. An effective vaccine is not yet available. Here, HSV-1 glycoprotein B (gB1) was delivered by a feline immunodeficiency virus (FIV) vector and tested against HSV-1 and HSV-2 vaginal challenges in C57BL/6 mice. The gB1 vaccine elicited cross-neutralizing antibodies and cell-mediated responses that protected 100 and 75% animals from HSV-1- and HSV-2-associated severe disease, respectively. Two of the eight fully protected vaccinees underwent subclinical HSV-2 infection, as demonstrated by deep immunosuppression and other analyses. Finally, vaccination prevented death in 83% of the animals challenged with a HSV-2 dose that killed 78 and 100% naive and mock-vaccinated controls, respectively. Since this FIV vector can accommodate two or more HSV immunogens, this vaccine has ample potential for improvement and may become a candidate for the development of a truly effective vaccine against genital herpes.


Assuntos
Proteção Cruzada , Herpes Genital/imunologia , Vacinas contra o Vírus do Herpes Simples/imunologia , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 2/fisiologia , Proteínas do Envelope Viral/imunologia , Animais , Feminino , Vetores Genéticos/genética , Vetores Genéticos/metabolismo , Herpes Genital/prevenção & controle , Herpes Genital/virologia , Vacinas contra o Vírus do Herpes Simples/administração & dosagem , Vacinas contra o Vírus do Herpes Simples/genética , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/imunologia , Humanos , Imunidade Celular , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Vacinação , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/genética
16.
New Microbiol ; 36(1): 1-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23435812

RESUMO

No matter what their origin, strain and family, viruses have evolved exquisite strategies to reach and penetrate specific target cells where they hijack the cellular machinery to express viral genes and produce progeny particles. The ability to deliver and express genetic information to cells is the basis for exploiting viruses as "Trojan horses" to genetically modify the natural cell target or, upon manipulation of the viral receptor to retarget the virus, to genetically engineer different cell types. This process, known as transduction, is accomplished using viral vectors derived from parental wild type viruses whose viral genes, essential for replication and virulence, have been replaced with the heterologous gene(s) required for cell manipulation. Rearrangement of the viral genome to impede replication or generation of infectious virions but maintaining the ability to deliver nucleic acids has been the object of intense research since the early 1980s. Technological advances and the ever-growing knowledge of molecular virology and virus-host cell relationships have constantly improved the safety profile of viral vectors that are now used in vitro and in vivo to study cellular gene function, correct genetic defects (gene therapy), express therapeutic proteins, vaccinate against infectious agents and tumors, produce experimental animal models, and for other purposes. This review illustrates the strategies used to generate some of the most used viral vectors, and their advantages, limitations and principal applications.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética/métodos , Vetores Genéticos , Vírus/genética , Animais , Humanos , Replicação Viral/fisiologia
17.
FEBS J ; 290(17): 4300-4315, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37098810

RESUMO

Mechanisms underlying vascular endothelial susceptibility to infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are not fully understood. Emerging evidence indicates that patients lacking von Willebrand factor (vWF), an endothelial hallmark, are less severely affected by SARS-CoV-2 infection, yet the precise role of endothelial vWF in modulating coronavirus entry into endothelial cells is unknown. In the present study, we demonstrated that effective gene silencing by short interfering RNA (siRNA) for vWF expression in resting human umbilical vein endothelial cells (HUVECs) significantly reduced by 56% the cellular levels of SARS-CoV-2 genomic RNA. Similar reduction in intracellular SARS-CoV-2 genomic RNA levels was observed in non-activated HUVECs treated with siRNA targeting angiotensin-converting enzyme 2 (ACE2), the cellular gateway to coronavirus. By integrating quantitative information from real-time PCR and high-resolution confocal imaging, we demonstrated that ACE2 gene expression and its plasma membrane localization in HUVECs were both markedly reduced after treatment with siRNA anti-vWF or anti-ACE2. Conversely, siRNA anti-ACE2 did not reduce endothelial vWF gene expression and protein levels. Finally, SARS-CoV-2 infection of viable HUVECs was enhanced by overexpression of vWF, which increased ACE2 levels. Of note, we found a similar increase in interferon-ß mRNA levels following transfection with untargeted, anti-vWF or anti-ACE2 siRNA and pcDNA3.1-WT-VWF. We envision that siRNA targeting endothelial vWF will protect against productive endothelial infection by SARS-CoV-2 through downregulation of ACE2 expression and might serve as a novel tool to induce disease resistance by modulating the regulatory role of vWF on ACE2 expression.


Assuntos
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo , Células Endoteliais/metabolismo , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , RNA Interferente Pequeno/genética , Inativação Gênica
18.
Sci Rep ; 13(1): 20138, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978212

RESUMO

Microglia chronic activation is a hallmark of several neurodegenerative diseases, including the retinal ones, possibly contributing to their etiopathogenesis. However, some microglia sub-populations have anti-inflammatory and neuroprotective functions, thus making arduous deciphering the role of these cells in neurodegeneration. Since it has been proposed that functionally different microglia subsets also rely on different metabolic routes, we hypothesized that modulating microglia metabolism might be a tool to enhance their anti-inflammatory features. This would have a preventive and therapeutic potential in counteracting neurodegenerative diseases. For this purpose, we tested various molecules known to act on cell metabolism, and we revealed the anti-inflammatory effect of the FDA-approved piperazine derivative Ranolazine on microglia cells, while confirming the one of the flavonoids Quercetin and Naringenin, both in vitro and in vivo. We also demonstrated the synergistic anti-inflammatory effect of Quercetin and Idebenone, and the ability of Ranolazine, Quercetin and Naringenin to counteract the neurotoxic effect of LPS-activated microglia on 661W neuronal cells. Overall, these data suggest that using the selected molecules -also in combination therapies- might represent a valuable approach to reduce inflammation and neurodegeneration while avoiding long term side effects of corticosteroids.


Assuntos
Doenças Neurodegenerativas , Fármacos Neuroprotetores , Humanos , Microglia/metabolismo , Ranolazina/farmacologia , Ranolazina/uso terapêutico , Quercetina/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Inflamação/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Lipopolissacarídeos/farmacologia , Fármacos Neuroprotetores/uso terapêutico
19.
Antiviral Res ; 216: 105664, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37414288

RESUMO

Recent evidence suggests that lipids play a crucial role in viral infections beyond their traditional functions of supplying envelope and energy, and creating protected niches for viral replication. In the case of Zika virus (ZIKV), it alters host lipids by enhancing lipogenesis and suppressing ß-oxidation to generate viral factories at the endoplasmic reticulum (ER) interface. This discovery prompted us to hypothesize that interference with lipogenesis could serve as a dual antiviral and anti-inflammatory strategy to combat the replication of positive sense single-stranded RNA (ssRNA+) viruses. To test this hypothesis, we examined the impact of inhibiting N-Acylethanolamine acid amidase (NAAA) on ZIKV-infected human Neural Stem Cells. NAAA is responsible for the hydrolysis of palmitoylethanolamide (PEA) in lysosomes and endolysosomes. Inhibition of NAAA results in PEA accumulation, which activates peroxisome proliferator-activated receptor-α (PPAR-α), directing ß-oxidation and preventing inflammation. Our findings indicate that inhibiting NAAA through gene-editing or drugs moderately reduces ZIKV replication by approximately one log10 in Human Neural Stem Cells, while also releasing immature virions that have lost their infectivity. This inhibition impairs furin-mediated prM cleavage, ultimately blocking ZIKV maturation. In summary, our study highlights NAAA as a host target for ZIKV infection.


Assuntos
Infecção por Zika virus , Zika virus , Humanos , Amidoidrolases/antagonistas & inibidores , Amidoidrolases/metabolismo , Anti-Inflamatórios/farmacologia , Inflamação/tratamento farmacológico , Infecção por Zika virus/tratamento farmacológico
20.
Stem Cell Reports ; 17(7): 1683-1698, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35714598

RESUMO

Congenital alterations in the levels of the transcription factor Forkhead box g1 (FOXG1) coding gene trigger "FOXG1 syndrome," a spectrum that recapitulates birth defects found in the "congenital Zika syndrome," such as microcephaly and other neurodevelopmental conditions. Here, we report that Zika virus (ZIKV) infection alters FOXG1 nuclear localization and causes its downregulation, thus impairing expression of genes involved in cell replication and apoptosis in several cell models, including human neural progenitor cells. Growth factors, such as EGF and FGF2, and Thr271 residue located in FOXG1 AKT domain, take part in the nuclear displacement and apoptosis protection, respectively. Finally, by progressive deletion of FOXG1 sequence, we identify the C-terminus and the residues 428-481 as critical domains. Collectively, our data suggest a causal mechanism by which ZIKV affects FOXG1, its target genes, cell cycle progression, and survival of human neural progenitors, thus contributing to microcephaly.


Assuntos
Microcefalia , Células-Tronco Neurais , Infecção por Zika virus , Zika virus , Regulação para Baixo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Humanos , Microcefalia/genética , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Células-Tronco Neurais/metabolismo , Zika virus/fisiologia , Infecção por Zika virus/genética
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