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1.
Analyst ; 149(13): 3537-3546, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38758167

RESUMO

Single nucleotide variants (SNVs) play a crucial role in understanding genetic diseases, cancer development, and personalized medicine. However, existing ligase-based amplification and detection techniques, such as Rolling Circle Amplification and Ligase Detection Reaction, suffer from low efficiency and difficulties in product detection. To address these limitations, we propose a novel approach that combines Ligase Chain Reaction (LCR) with acoustic detection using highly dissipative liposomes. In our study, we are using LCR combined with biotin- and cholesterol-tagged primers to produce amplicons also modified at each end with a biotin and cholesterol molecule. We then apply the LCR mix without any purification directly on a neutravidin modified QCM device Au-surface, where the produced amplicons can bind specifically through the biotin end. To improve sensitivity, we finally introduce liposomes as signal enhancers. For demonstration, we used the detection of the BRAF V600E point mutation versus the wild-type allele, achieving an impressive detection limit of 220 aM of the mutant target in the presence of the same amount of the wild type. Finally, we combined the assay with a microfluidic fluidized bed DNA extraction technology, offering the potential for semi-automated detection of SNVs in patients' crude samples. Overall, our LCR/acoustic method outperforms other LCR-based approaches and surface ligation biosensing techniques in terms of detection efficiency and time. It effectively overcomes challenges related to DNA detection, making it applicable in diverse fields, including genetic disease and pathogen detection.


Assuntos
Reação em Cadeia da Ligase , Limite de Detecção , Lipossomos , Lipossomos/química , Humanos , Reação em Cadeia da Ligase/métodos , Proteínas Proto-Oncogênicas B-raf/genética , Polimorfismo de Nucleotídeo Único , Biotina/química , Acústica , Avidina/química , Técnicas de Microbalança de Cristal de Quartzo/métodos , Ouro/química , DNA/genética , DNA/química , Colesterol , Mutação Puntual
2.
Crit Rev Microbiol ; : 1-25, 2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37348003

RESUMO

Lipids play essential roles in the cell as components of cellular membranes, signaling molecules, and energy storage sources. Lipid droplets are cellular organelles composed of neutral lipids, such as triglycerides and cholesterol esters, and are also considered as cellular energy reserves, yet new functions have been recently associated with these structures, such as regulators of oxidative stress and cellular lipotoxicity, as well as modulators of pathogen infection through immune regulation. Lipid metabolism and lipid droplets participate in the infection process of many RNA viruses and control their replication and assembly, among others. Here, we review and discuss the contribution of lipid metabolism and lipid droplets over the replication cycle of RNA viruses, altogether pointing out potentially new pharmacological antiviral targets associated with lipid metabolism.

3.
Mol Psychiatry ; 26(7): 2837-2853, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33767348

RESUMO

The high comorbidity between obesity and mental disorders, such as depression and anxiety, often exacerbates metabolic and neurological symptoms significantly. However, neural mechanisms that underlie reciprocal control of feeding and mental states are largely elusive. Here we report that melanocortin 4 receptor (MC4R) neurons located in the dorsal bed nucleus of the stria terminus (dBNST) engage in the regulation of mentally associated weight gain by receiving GABAergic projections from hypothalamic AgRP neurons onto α5-containing GABAA receptors and serotonergic afferents onto 5-HT3 receptors. Chronic treatment with a high-fat diet (HFD) significantly blunts the hyperexcitability of AgRP neurons in response to not only hunger but also anxiety and depression-like stimuli. Such HFD-mediated desensitization reduces GABAergic outputs from AgRP neurons to downstream MC4RdBNST neurons, resulting in severe mental dysregulation. Genetic enhancement of the GABAAR-α5 or suppression of the 5-HT3R within the MC4RdBNST neurons not only abolishes HFD-induced anxiety and depression but also robustly reduces body weight by suppression of food intake. To gain further translational insights, we revealed that combined treatment of zonisamide (enhancing the GABAAR-α5 signaling) and granisetron (a selective 5-HT3R antagonist) alleviates mental dysfunction and yields a robust reversal of diet-induced obesity by reducing total calorie intake and altering food preference towards a healthy low-fat diet. Our results unveil a neural mechanism for reciprocal control of appetite and mental states, which culminates in a novel zonisamide-granisetron cocktail therapy for potential tackling the psychosis-obesity comorbidity.


Assuntos
Transtorno Depressivo , Serotonina , Proteína Relacionada com Agouti , Ansiedade , Depressão , Humanos , Obesidade , Ácido gama-Aminobutírico
4.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360716

RESUMO

Oxygen is essential for aerobic cells, and thus its sensing is critical for the optimal maintenance of vital cellular and tissue processes such as metabolism, pH homeostasis, and angiogenesis, among others. Hypoxia-inducible factors (HIFs) play central roles in oxygen sensing. Under hypoxic conditions, the α subunit of HIFs is stabilized and forms active heterodimers that translocate to the nucleus and regulate the expression of important sets of genes. This process, in turn, will induce several physiological changes intended to adapt to these new and adverse conditions. Over the last decades, numerous studies have reported a close relationship between viral infections and hypoxia. Interestingly, this relation is somewhat bidirectional, with some viruses inducing a hypoxic response to promote their replication, while others inhibit hypoxic cellular responses. Here, we review and discuss the cellular responses to hypoxia and discuss how HIFs can promote a wide range of physiological and transcriptional changes in the cell that modulate numerous human viral infections.


Assuntos
Fator 1 Induzível por Hipóxia/metabolismo , Consumo de Oxigênio , Viroses/metabolismo , Replicação Viral , Vírus/metabolismo , Hipóxia Celular , Humanos , Viroses/patologia
5.
Proc Natl Acad Sci U S A ; 113(13): 3645-50, 2016 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-26976589

RESUMO

Currently available inducible Cre/loxP systems, despite their considerable utility in gene manipulation, have pitfalls in certain scenarios, such as unsatisfactory recombination rates and deleterious effects on physiology and behavior. To overcome these limitations, we designed a new, inducible gene-targeting system by introducing an in-frame nonsense mutation into the coding sequence of Cre recombinase (nsCre). Mutant mRNAs transcribed from nsCre transgene can be efficiently translated into full-length, functional Cre recombinase in the presence of nonsense suppressors such as aminoglycosides. In a proof-of-concept model, GABA signaling from hypothalamic neurons expressing agouti-related peptide (AgRP) was genetically inactivated within 4 d after treatment with a synthetic aminoglycoside. Disruption of GABA synthesis in AgRP neurons in young adult mice led to a dramatic loss of body weight due to reduced food intake and elevated energy expenditure; they also manifested glucose intolerance. In contrast, older mice with genetic inactivation of GABA signaling by AgRP neurons had only transient reduction of feeding and body weight; their energy expenditure and glucose tolerance were unaffected. These results indicate that GABAergic signaling from AgRP neurons plays a key role in the control of feeding and metabolism through an age-dependent mechanism. This new genetic technique will augment current tools used to elucidate mechanisms underlying many physiological and neurological processes.


Assuntos
Metabolismo Energético/genética , Metabolismo Energético/fisiologia , Comportamento Alimentar/fisiologia , Ácido gama-Aminobutírico/fisiologia , Proteína Relacionada com Agouti/deficiência , Proteína Relacionada com Agouti/genética , Proteína Relacionada com Agouti/fisiologia , Animais , Engenharia Genética , Glutamato Descarboxilase/deficiência , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/fisiologia , Hipotálamo/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais
6.
Analyst ; 142(3): 485-494, 2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28098263

RESUMO

A microdevice combining online preconcentration and separation of phosphopeptides was developed in a glass microchip. An ethylene glycol methacrylate phosphate (EGMP), acrylamide (AM) and bisacrylamide (BAA) based monolith was synthesized within microchannels through a photo-driven process. Morphological investigations revealed a homogeneous monolithic structure composed of uniform nodules (∼0.8 µm), with a large pore volume (0.62 cm3 g-1) and sufficiently high specific surface area (34.1 m2 g-1). These features make the monolith particularly interesting for preconcentration purposes. Immobilization of Zr4+ ions on the phosphate groups present at the poly(EGMP-co-AM-co-BAA) monolith surface leads to immobilized metal affinity chromatography support. This monolith-Zr4+ showed a great capacity to capture phosphopeptides. Successful preconcentration and separation of a mixture of ERK2 derived peptides differing only by their phosphorylation degree and sites could be achieved with signal enhancement factors between 340 and 910 after only 7 min of preconcentration. This integrated microdevice represents a novel approach for phosphoproteomic applications.


Assuntos
Eletroforese , Dispositivos Lab-On-A-Chip , Fosfopeptídeos/isolamento & purificação , Cromatografia de Afinidade , Vidro
7.
Anal Bioanal Chem ; 409(8): 2155-2162, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28028588

RESUMO

Herein, highly defined monolithic beds were prepared in glass microchips by photopolymerization of ethylene glycol methacrylate phosphate (EGMP), acrylamide, and N,N'-methylenebisacrylamide (BAA) using an epifluorescence microscope as UV-irradiation source. Such a fast and easy method allowed precise control of (i) the edge shape, (ii) the location along the microchannel, and (iii) the length of the monolithic plugs within glass microchips. The addition of hydroquinone, a polymerization inhibitor, to the prepolymerization mixture was beneficial for achieving local and robust incorporation of monoliths with sharp edges within microchannels. The monolith length was easily tuned from 160 to 400 µm through simple change in the magnification of the objective and was found to be repeatable (relative standard deviation <7.5%). Further application for on-chip monolith-assisted solid - phase extraction is demonstrated for fluorescently labeled peptide. Both binding and subsequent elution behaviors were found to fully agree with a cation-exchange mechanism in concordance with the presence of phosphate groups at the monolith surface. Graphical abstract In-chip microscope-UV-synthesis of monolithic plugs with sharp edges.


Assuntos
Vidro , Microscopia/métodos , Peptídeos/química , Polímeros , Raios Ultravioleta/efeitos adversos , Porosidade
8.
Foods ; 13(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38790824

RESUMO

The impact of cryogenic pretreatments on drying performance was studied in blueberries, seabuckthorn fruits and green grapes. The fruits were immersed in liquid nitrogen in 2 min freezing/thawing cycles (one to five). Untreated samples were used as the control. Drying experiments were carried out on treated and non-treated berries at 50 °C and 1 m/s (hot-air-drying), 50 °C and 25″ Hg vacuum (vacuum-drying), 30 mTorr total pressure and 25 °C shelf temperature (freeze-drying). The weight loss evolution of the foodstuffs was measured as a function of time. Microscopic (SEM and optical) determinations of the epicarp were performed. A visual inspection was performed and color changes and volume reductions were assessed before and after dehydration. The thickness of the berries' epicarp decreased between 20 and 50% (depending on the fruit) after 3-5 immersions in liquid N2. The drying kinetics was accelerated significantly for the three tested drying processes (i.e., drying time decreased from 48 to 16 h for blueberry freeze-drying). The best quality of dried berries was observed for pretreated blueberries after freeze-drying, keeping their volume, shape and color after the process. This work shows that "tailor-made" dried berry products with desired properties can be achieved and drying performance can be improved by the application of ultra-low temperature pretreatments.

9.
Commun Biol ; 7(1): 811, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965360

RESUMO

Experimental autoimmune encephalomyelitis (EAE) is a demyelinating disease affecting the central nervous system (CNS) in animals that parallels several clinical and molecular traits of multiple sclerosis in humans. Herpes simplex virus type 1 (HSV-1) infection mainly causes cold sores and eye diseases, yet eventually, it can also reach the CNS, leading to acute encephalitis. Notably, a significant proportion of healthy individuals are likely to have asymptomatic HSV-1 brain infection with chronic brain inflammation due to persistent latent infection in neurons. Because cellular senescence is suggested as a potential factor contributing to the development of various neurodegenerative disorders, including multiple sclerosis, and viral infections may induce a premature senescence state in the CNS, potentially increasing susceptibility to such disorders, here we examine the presence of senescence-related markers in the brains and spinal cords of mice with asymptomatic HSV-1 brain infection, EAE, and both conditions. Across all scenarios, we find a significant increases of senescence biomarkers in the CNS with some differences depending on the analyzed group. Notably, some senescence biomarkers are exclusively observed in mice with the combined conditions. These results indicate that asymptomatic HSV-1 brain infection and EAE associate with a significant expression of senescence biomarkers in the CNS.


Assuntos
Encéfalo , Senescência Celular , Herpes Simples , Herpesvirus Humano 1 , Esclerose Múltipla , Animais , Camundongos , Encéfalo/virologia , Encéfalo/patologia , Encéfalo/metabolismo , Esclerose Múltipla/virologia , Esclerose Múltipla/patologia , Esclerose Múltipla/metabolismo , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 1/patogenicidade , Herpes Simples/virologia , Herpes Simples/patologia , Feminino , Camundongos Endogâmicos C57BL , Encefalomielite Autoimune Experimental/virologia , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/metabolismo , Fenótipo , Sistema Nervoso Central/virologia , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Medula Espinal/virologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Biomarcadores/metabolismo , Encefalite por Herpes Simples/virologia , Encefalite por Herpes Simples/patologia , Encefalite por Herpes Simples/metabolismo
10.
Methods Mol Biol ; 2804: 65-75, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753140

RESUMO

In recent years, the analysis of circulating cell-free DNA (cfDNA) containing tumor-derived DNA has emerged as a noninvasive means for cancer monitoring and personalized medicine. However, the isolation of cfDNA from peripheral blood has remained a challenge due to the low abundance and high fragmentation of these molecules. Here, we present a dynamic Magnetic ExTRactiOn (METRO) protocol using microfluidic fluidized bed technology to isolate circulating cfDNA from raw biological materials such as undiluted serum. This protocol maximizes the surface area for DNA binding within the chip in order to capture short DNA fragments. It uses only a few µL of sample and reagents. The protocol can be automated, and it is fully compatible with sensitive DNA amplification methods such as droplet-based digital PCR (ddPCR).


Assuntos
Ácidos Nucleicos Livres , Dispositivos Lab-On-A-Chip , Humanos , Ácidos Nucleicos Livres/isolamento & purificação , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/genética , Reação em Cadeia da Polimerase/métodos , Técnicas Analíticas Microfluídicas/métodos , Técnicas Analíticas Microfluídicas/instrumentação , Magnetismo/métodos , Neoplasias/sangue , Neoplasias/genética , Neoplasias/diagnóstico
11.
Gynecol Oncol ; 131(2): 357-61, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23988418

RESUMO

OBJECTIVES: A two-stage, single-arm, phase II study was conducted to assess the effectiveness and safety of an epigallocatechin gallate (EGCG)-enriched tea drink, the double-brewed green tea (DBGT), as a maintenance treatment in women with advanced stage serous or endometrioid ovarian cancer (clinicaltrials.gov, NCT00721890). METHODS: Eligible women had FIGO stage III-IV serous or endometrioid ovarian cancer. They had to undergo complete response after debulking surgery followed by 6 to 8 cycles of platinum/taxane chemotherapy at the Centre Hospitalier Universitaire de Québec. They all had to drink the DBGT, 500 mL daily until recurrence or during a follow-up of 18 months. The primary endpoint was the absence of recurrence at 18 months. Statistical analyses were done according to the principle of intention to treat. Using a two-stage design, the first stage consisted of 16 enrolled patients. At the end of the follow-up, if 7 or fewer patients were free of recurrence, the trial stopped. Otherwise, accrual would continue to a total of 46 patients. RESULTS: During the first stage of the study, only 5 of the 16 women remained free of recurrence 18 months after complete response. Accordingly, the clinical trial was terminated. Women's adherence to DBGT was high (median daily intake during intervention, 98.1%, interquartile range: 89.7-100%), but 6 women discontinued the intervention before the end of their follow-up. No severe toxicity was reported. CONCLUSIONS: DBGT supplementation does not appear to be a promising maintenance intervention in women with advanced stage ovarian cancer after standard treatment.


Assuntos
Catequina/análogos & derivados , Neoplasias Ovarianas/tratamento farmacológico , Chá , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Endometrioide/tratamento farmacológico , Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/cirurgia , Catequina/administração & dosagem , Catequina/efeitos adversos , Terapia Combinada , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/patologia , Cistadenocarcinoma Seroso/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Quimioterapia de Manutenção , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Compostos Organoplatínicos/administração & dosagem , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , Taxoides/administração & dosagem
12.
Antioxidants (Basel) ; 12(6)2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37371900

RESUMO

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections are highly prevalent in the human population and produce mild to life-threatening diseases. These viruses interfere with the function and viability of dendritic cells (DCs), which are professional antigen-presenting cells that initiate and regulate the host's antiviral immune responses. Heme oxygenase-1 (HO-1) is an inducible host enzyme with reported antiviral activity against HSVs in epithelial cells and neurons. Here, we sought to assess whether HO-1 modulates the function and viability of DCs upon infection with HSV-1 or HSV-2. We found that the stimulation of HO-1 expression in HSV-inoculated DCs significantly recovered the viability of these cells and hampered viral egress. Furthermore, HSV-infected DCs stimulated to express HO-1 promoted the expression of anti-inflammatory molecules, such as PDL-1 and IL-10, and the activation of virus-specific CD4+ T cells with regulatory (Treg), Th17 and Treg/Th17 phenotypes. Moreover, HSV-infected DCs stimulated to express HO-1 and then transferred into mice, promoted the activation of virus-specific T cells and improved the outcome of HSV-1 skin infection. These findings suggest that stimulation of HO-1 expression in DCs limits the deleterious effects of HSVs over these cells and induces a favorable virus-specific immune response in the skin against HSV-1.

13.
Microsyst Nanoeng ; 9: 109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37680311

RESUMO

Liquid biopsy, in particular circulating tumor DNA (ctDNA) analysis, has paved the way for a new noninvasive approach to cancer diagnosis, treatment selection and follow-up. As a crucial step in the analysis, the extraction of the genetic material from a complex matrix needs to meet specific requirements such as high specificity and low loss of target. Here, we developed a new generation of microfluidic fluidized beds (FBs) that enable the efficient extraction and preconcentration of specific ctDNA sequences from human serum with flow rates up to 15 µL/min. We first demonstrated that implementation of a vibration system inducing flow rate fluctuations combined with a mixture of different bead sizes significantly enhanced bead homogeneity, thereby increasing capture efficiency. Taking advantage of this new generation of high-throughput magnetic FBs, we then developed a new method to selectively capture a double-stranded (dsDNA) BRAF mutated DNA sequence in complex matrices such as patient serum. Finally, as proof of concept, ligation chain reaction (LCR) assays were performed to specifically amplify a mutated BRAF sequence, allowing the detection of concentrations as low as 6 × 104 copies/µL of the mutated DNA sequence in serum.

14.
Cells ; 11(14)2022 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-35883666

RESUMO

Lipid droplets (LDs) are cellular organelles rich in neutral lipids such as triglycerides and cholesterol esters that are coated by a phospholipid monolayer and associated proteins. LDs are known to play important roles in the storage and availability of lipids in the cell and to serve as a source of energy reserve for the cell. However, these structures have also been related to oxidative stress, reticular stress responses, and reduced antigen presentation to T cells. Importantly, LDs are also known to modulate viral infection by participating in virus replication and assembly. Here, we review and discuss the interplay between neutral lipid metabolism and LDs in the replication cycle of different DNA viruses, identifying potentially new molecular targets for the treatment of viral infections.


Assuntos
Infecções por Vírus de DNA , Gotículas Lipídicas , Ésteres do Colesterol/metabolismo , Humanos , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos/fisiologia , Triglicerídeos/metabolismo
15.
Antioxidants (Basel) ; 11(6)2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35739937

RESUMO

An important virulence trait of Salmonella enterica serovar Typhimurium (S. Typhimurium) is the ability to avoid the host immune response, generating systemic and persistent infections. Host cells play a crucial role in bacterial clearance by expressing the enzyme heme oxygenase 1 (Hmox1), which catalyzes the degradation of heme groups into Fe2+, biliverdin, and carbon monoxide (CO). The role of Hmox1 activity during S. Typhimurium infection is not clear and previous studies have shown contradictory results. We evaluated the effect of pharmacologic modulation of Hmox1 in a mouse model of acute and persistent S. Typhimurium infection by administering the Hmox1 activity inductor cobalt protoporphyrin-IX (CoPP) or inhibitor tin protoporphyrin-IX (SnPP) before infection. To evaluate the molecular mechanism involved, we measured the colocalization of S. Typhimurium and autophagosome and lysosomal markers in macrophages. Administering CoPP reduced the bacterial burden in organs of mice 5 days post-infection, while SnPP-treated mice showed bacterial loads similar to vehicle-treated mice. Furthermore, CoPP reduced bacterial loads when administered after infection in macrophages in vitro and in a persistent infection model of S. Typhimurium in vivo, while tin protoporphyrin-IX (SnPP) treatment resulted in a bacterial burden similar to vehicle-treated controls. However, we did not observe significant differences in co-localization of green fluorescent protein (GFP)-labeled S. Typhimurium with the autophagic vesicles marker microtubule-associated protein 1A/1B-light chain 3 (LC3) and the lysosomal marker lysosomal-associated membrane protein 1 (LAMP-1) in macrophages treated with CoPP. Our results suggest that CoPP can enhance antimicrobial activity in response to Salmonella infection, reducing bacterial dissemination and persistence in mice, in a CO and autophagy- independent manner.

16.
Sci Adv ; 7(22)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34039606

RESUMO

The neural circuitry mechanism that underlies dopaminergic (DA) control of innate feeding behavior is largely uncharacterized. Here, we identified a subpopulation of DA neurons situated in the caudal ventral tegmental area (cVTA) directly innervating DRD1-expressing neurons within the lateral parabrachial nucleus (LPBN). This neural circuit potently suppresses food intake via enhanced satiation response. Notably, this cohort of DAcVTA neurons is activated immediately before the cessation of each feeding bout. Acute inhibition of these DA neurons before bout termination substantially suppresses satiety and prolongs the consummatory feeding. Activation of postsynaptic DRD1LPBN neurons inhibits feeding, whereas genetic deletion of Drd1 within the LPBN causes robust increase in food intake and subsequent weight gain. Furthermore, the DRD1LPBN signaling manifests the central mechanism in methylphenidate-induced hypophagia. In conclusion, our study illuminates a hindbrain DAergic circuit that controls feeding through dynamic regulation in satiety response and meal structure.


Assuntos
Ingestão de Alimentos , Saciação , Animais , Ingestão de Alimentos/fisiologia , Humanos , Ratos , Ratos Sprague-Dawley , Rombencéfalo , Saciação/fisiologia , Aumento de Peso
17.
Front Immunol ; 12: 662234, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34012447

RESUMO

Herpes simplex virus type 1 (HSV-1) infection is highly prevalent in humans, with approximately two-thirds of the world population living with this virus. However, only a fraction of those carrying HSV-1, which elicits lifelong infections, are symptomatic. HSV-1 mainly causes lesions in the skin and mucosae but reaches the termini of sensory neurons innervating these tissues and travels in a retrograde manner to the neuron cell body where it establishes persistent infection and remains in a latent state until reactivated by different stimuli. When productive reactivations occur, the virus travels back along axons to the primary infection site, where new rounds of replication are initiated in the skin, in recurrent or secondary infections. During this process, new neuron infections occur. Noteworthy, the mechanisms underlying viral reactivations and the exit of latency are somewhat poorly understood and may be regulated by a crosstalk between the infected neurons and components of the immune system. Here, we review and discuss the immune responses that occur at the skin during primary and recurrent infections by HSV-1, as well as at the interphase of latently-infected neurons. Moreover, we discuss the implications of neuronal signals over the priming and migration of immune cells in the context of HSV-1 infection.


Assuntos
Células Epiteliais/metabolismo , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Células Receptoras Sensoriais/metabolismo , Dermatopatias Virais/imunologia , Animais , Técnicas de Cultura de Células , Células Epiteliais/imunologia , Regulação Viral da Expressão Gênica , Herpesvirus Humano 1/genética , Humanos , Camundongos , Células Receptoras Sensoriais/imunologia , Ativação Viral , Latência Viral , Replicação Viral
18.
Nat Commun ; 12(1): 3525, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112797

RESUMO

Contrasting to the established role of the hypothalamic agouti-related protein (AgRP) neurons in feeding regulation, the neural circuit and signaling mechanisms by which they control energy expenditure remains unclear. Here, we report that energy expenditure is regulated by a subgroup of AgRP neurons that send non-collateral projections to neurons within the dorsal lateral part of dorsal raphe nucleus (dlDRN) expressing the melanocortin 4 receptor (MC4R), which in turn innervate nearby serotonergic (5-HT) neurons. Genetic manipulations reveal a bi-directional control of energy expenditure by this circuit without affecting food intake. Fiber photometry and electrophysiological results indicate that the thermo-sensing MC4RdlDRN neurons integrate pre-synaptic AgRP signaling, thereby modulating the post-synaptic serotonergic pathway. Specifically, the MC4RdlDRN signaling elicits profound, bi-directional, regulation of body weight mainly through sympathetic outflow that reprograms mitochondrial bioenergetics within brown and beige fat while feeding remains intact. Together, we suggest that this AgRP neural circuit plays a unique role in persistent control of energy expenditure and body weight, hinting next-generation therapeutic approaches for obesity and metabolic disorders.


Assuntos
Proteína Relacionada com Agouti/metabolismo , Metabolismo Energético/fisiologia , Hipotálamo/metabolismo , Condução Nervosa/fisiologia , Neurônios Serotoninérgicos/fisiologia , Tecido Adiposo Bege/metabolismo , Tecido Adiposo Marrom/metabolismo , Animais , Peso Corporal , Cromatografia Líquida , Ingestão de Alimentos/fisiologia , Metabolismo Energético/genética , Masculino , Camundongos , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/efeitos da radiação , Obesidade/metabolismo , Optogenética , Receptor Tipo 4 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/metabolismo , Neurônios Serotoninérgicos/efeitos dos fármacos , Neurônios Serotoninérgicos/efeitos da radiação , Serotonina/metabolismo , Serotonina/fisiologia , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Espectrometria de Massas em Tandem , Temperatura
19.
Front Immunol ; 12: 764861, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069537

RESUMO

Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections are life-long and highly prevalent in the human population. These viruses persist in the host, eliciting either symptomatic or asymptomatic infections that may occur sporadically or in a recurrent manner through viral reactivations. Clinical manifestations due to symptomatic infection may be mild such as orofacial lesions, but may also translate into more severe diseases, such as ocular infections that may lead to blindness and life-threatening encephalitis. A key feature of herpes simplex viruses (HSVs) is that they have evolved molecular determinants that hamper numerous components of the host's antiviral innate and adaptive immune system. Importantly, HSVs infect and negatively modulate the function of dendritic cells (DCs), by inhibiting their T cell-activating capacity and eliciting their apoptosis after infection. Previously, we reported that HSV-2 activates the splicing of the mRNA of XBP1, which is related to the activity of the unfolded protein response (UPR) factor Inositol-Requiring Enzyme 1 alpha (IRE-1α). Here, we sought to evaluate if the activation of the IRE-1α pathway in DCs upon HSV infection may be related to impaired DC function after infection with HSV-1 or HSV-2. Interestingly, the pharmacological inhibition of the endonuclease activity of IRE-1α in HSV-1- and HSV-2-infected DCs significantly reduced apoptosis in these cells and enhanced their capacity to migrate to lymph nodes and activate virus-specific CD4+ and CD8+ T cells. These findings suggest that the activation of the IRE-1α-dependent UPR pathway in HSV-infected DCs may play a significant role in the negative effects that these viruses exert over these cells and that the modulation of this signaling pathway may be relevant for enhancing the function of DCs upon infection with HSVs.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Endorribonucleases/antagonistas & inibidores , Herpes Genital/imunologia , Herpesvirus Humano 1/imunologia , Herpesvirus Humano 2/imunologia , Ativação Linfocitária , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Animais , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Chlorocebus aethiops , Células Dendríticas/virologia , Endorribonucleases/imunologia , Feminino , Camundongos , Proteínas Serina-Treonina Quinases/imunologia , Células Vero
20.
Front Microbiol ; 11: 2006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013743

RESUMO

Herpes simplex viruses (HSVs) type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent in the human population, and the infections they produce are lifelong with frequent reactivations throughout life. Both viruses produce uncomfortable and sometimes painful lesions in the orofacial and genital areas, as well as herpetic gingivostomatitis, among other clinical manifestations. At present, the most common treatments against HSVs consist of nucleoside analogs that target the viral polymerases. However, such drugs are poorly effective for treating skin lesions, as they only reduce in 1-2 days the duration of the herpetic lesions. Additionally, viral isolates resistant to these drugs can emerge in immunosuppressed individuals, and second-line drugs for such variants are frequently accompanied by adverse effects requiring medical supervision. Thus, novel or improved therapeutic drugs for treating HSV lesions are needed. Here, we assessed the potential antiviral activity of aqueous extracts obtained from two brown macroalgae, namely Macrocystis pyrifera and Durvillaea antarctica against HSVs. Both extracts showed antiviral activity against acyclovir-sensitive and acyclovir-resistant HSV-1 and HSV-2. Our analyses show that there is a significant antiviral activity associated with proteins in the extract, although other compounds also seem to contribute to inhibiting the replication cycle of these viruses. Evaluation of the algae extracts as topical formulations in an animal model of HSV-1 skin infection significantly reduced the severity of the disease more than acyclovir, as well as the duration of the herpetic lesions, when compared to mock-treated animals, with the D. antarctica extract performing best. Taken together, these findings suggest that these algae extracts may be potential phytotherapeutics against HSVs and may be useful for the treatment and reduction of common herpetic manifestations in humans.

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