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1.
J Urol ; 209(5): 937-949, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36657058

RESUMO

PURPOSE: Interstitial cystitis/bladder pain syndrome is a chronic urological condition diagnosed in nearly 8 million females in the United States. Whether urinary microbiota play an etiological role remains controversial. Most studies assessed the microbiota of interstitial cystitis/bladder pain syndrome patients with voided or catheterized urine as a proxy for bladder urothelium; however, urine may not be a true reflection of the bladder microbiota. Bladder biopsy tissue may provide a more accurate, and thus more clinically relevant, picture of bladder microbiota. MATERIALS AND METHODS: Bladder biopsy tissues were obtained from: (1) 30 females with interstitial cystitis/bladder pain syndrome (18-80 years old) via cystoscopically guided cold-cup biopsy following therapeutic bladder hydrodistention, and (2) 10 non-interstitial cystitis/bladder pain syndrome females undergoing pelvic organ prolapse repair. To detect bacteria, technical duplicates of each RNAlater-preserved biopsy were subjected to 16S rRNA gene sequencing. To visualize bacteria, paraformaldehyde-fixed, paraffin-embedded biopsies were subjected to a combined multiplexed fluorescence in situ hybridization and fluorescence immunohistochemistry assay and confocal microscopy. RESULTS: Bacteria were detected by 16S rRNA gene sequencing in at least 1 technical duplicate of most biopsies. The most abundant genus was Staphylococcus, followed by Lactobacillus; Escherichia was common but not abundant. There was no significant difference between interstitial cystitis/bladder pain syndrome patients and controls (P > .05). Combined fluorescence in situ hybridization and immunohistochemistry reproducibly detected 16S rRNA in epithelial cells and shed cells in the urothelium and lesioned areas and capillary walls in the lamina propria of human bladder biopsy tissue. CONCLUSIONS: We conclude that urothelial and urinary microbiota are similar but not identical in adult females.


Assuntos
Cistite Intersticial , Bexiga Urinária , Adulto , Humanos , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Bexiga Urinária/patologia , Cistite Intersticial/diagnóstico , Hibridização in Situ Fluorescente , RNA Ribossômico 16S , Doença Crônica , Mucosa/patologia , Bactérias/genética
2.
J Virol ; 93(14)2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31043534

RESUMO

Several host and viral processes contribute to forming infectious virions. Polyamines are small host molecules that play diverse roles in viral replication. We previously demonstrated that polyamines are crucial for RNA viruses; however, the mechanisms by which polyamines function remain unknown. Here, we investigated the role of polyamines in the replication of the bunyaviruses Rift Valley fever virus (vaccine strain MP-12) and La Crosse virus (LACV). We found that polyamine depletion did not impact viral RNA or protein accumulation, despite significant decreases in titer. Viral particles demonstrated no change in morphology, size, or density. Thus, polyamine depletion promotes the formation of noninfectious particles. These particles interfere with virus replication and stimulate innate immune responses. We extended this phenotype to Zika virus; however, coxsackievirus did not similarly produce noninfectious particles. In sum, polyamine depletion results in the accumulation of noninfectious particles that interfere with replication and stimulate immune signaling, with important implications for targeting polyamines therapeutically, as well as for vaccine strategies.IMPORTANCE Bunyaviruses are emerging viral pathogens that cause encephalitis, hemorrhagic fevers, and meningitis. We have uncovered that diverse bunyaviruses require polyamines for productive infection. Polyamines are small, positively charged host-derived molecules that play diverse roles in human cells and in infection. In polyamine-depleted cells, bunyaviruses produce an overabundance of noninfectious particles that are indistinguishable from infectious particles. However, these particles interfere with productive infection and stimulate antiviral signaling pathways. We further find that additional enveloped viruses are similarly sensitive to polyamine depletion but that a nonenveloped enterovirus is not. We posit that polyamines are required to maintain bunyavirus infectivity and that polyamine depletion results in the accumulation of interfering noninfectious particles that limit infectivity. These results highlight a novel means by which bunyaviruses use polyamines for replication and suggest promising means to target host polyamines to reduce virus replication.


Assuntos
Poliaminas Biogênicas/imunologia , Infecções por Bunyaviridae/imunologia , Vírus Defeituosos/fisiologia , Vírus da Encefalite da Califórnia/fisiologia , Vírus da Febre do Vale do Rift/fisiologia , Vírion/fisiologia , Replicação Viral/imunologia , Infecções por Bunyaviridae/genética , Infecções por Bunyaviridae/patologia , Linhagem Celular Tumoral , Humanos
3.
Biochem Biophys Res Commun ; 503(4): 2306-2311, 2018 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-29966650

RESUMO

ALIS are large, transient, cytosolic aggregates that serve as storage compartments for ubiquitin-tagged defective ribosomal products. We determined the importance of the protein p62 in the formation of ALIS and demonstrated that two domains of p62-PB1 and UBA-are essential for ALIS assembly. Those two major binding domains of p62, also known as sequestosome 1, were shown to play a critical role in the formation of autophagosomes or cytoplasmic aggregates. Specifically, the PB1 domain is essential for self-oligomerization, and the UBA domain allows p62 to bind to polyubiquitin chains or ubiquitinated proteins. After stimulation of RAW 264.7 macrophages with lipopolysaccharide, we observed a significant decrease in the number of cells with ALIS. Importantly, cells overexpressing either a PB1 mutant or UBA-deleted p62 construct also exhibited a substantially diminished number of cells containing ALIS. Since both p62 and ubiquitin are found in ALIS, we evaluated the dynamics of YFP-tagged p62 in ALIS. In contrast to the findings of a previous study that evaluated GFP-tagged ubiquitin motility in ALIS, we determined that YFP-tagged p62 has very limited mobility. Lastly, we determined that GST-tagged full-length p62 binds to Lys-63-linked polyubiquitin chains but not to Lys-48-linked chains. Overall, our findings provide insight on the essential role that p62, particularly its PB1 and UBA domains, has in the formation of ALIS.


Assuntos
Citosol/ultraestrutura , Poliubiquitina/metabolismo , Agregados Proteicos/fisiologia , Proteína Sequestossoma-1/química , Ubiquitina/metabolismo , Animais , Citosol/química , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Ligação Proteica , Domínios Proteicos , Células RAW 264.7
4.
Neurobiol Dis ; 77: 191-203, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25771169

RESUMO

Advanced age is the primary risk factor for Parkinson's disease (PD). In PD patients and rodent models of PD, advanced age is associated with inferior symptomatic benefit following intrastriatal grafting of embryonic dopamine (DA) neurons, a pattern believed to result from decreased survival and reinnervation provided by grafted neurons in the aged host. To help understand the capacity of the aged, parkinsonian striatum to be remodeled with new DA terminals, we used a grafting model and examined whether increasing the number of grafted DA neurons in aged rats would translate to enhanced behavioral recovery. Young (3months), middle-aged (15months), and aged (22months) parkinsonian rats were grafted with proportionately increasing numbers of embryonic ventral mesencephalic (VM) cells to evaluate whether the limitations of the graft environment in subjects of advancing age can be offset by increased numbers of transplanted neurons. Despite robust survival of grafted neurons in aged rats, reinnervation of striatal neurons remained inferior and amelioration of levodopa-induced dyskinesias (LID) was delayed or absent. This study demonstrates that: 1) counter to previous evidence, under certain conditions the aged striatum can support robust survival of grafted DA neurons; and 2) unknown factors associated with the aged striatum result in inferior integration of graft and host, and continue to present obstacles to full therapeutic efficacy of DA cell-based therapy in this model of aging.


Assuntos
Envelhecimento , Corpo Estriado/fisiologia , Neurônios Dopaminérgicos/fisiologia , Doença de Parkinson/cirurgia , Recuperação de Função Fisiológica/fisiologia , Transplante de Células-Tronco/métodos , Anfetamina/farmacologia , Animais , Corpo Estriado/cirurgia , Modelos Animais de Doenças , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Discinesia Induzida por Medicamentos/fisiopatologia , Embrião de Mamíferos , Lateralidade Funcional , Levodopa/efeitos adversos , Neuritos/fisiologia , Oxidopamina/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Endogâmicos F344 , Substância P/metabolismo
5.
Eur J Neurosci ; 41(2): 205-15, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25359418

RESUMO

Context-drug learning produces structural and functional synaptic changes in the circuitry of the basolateral nucleus of the amygdala (BLA). However, how the synaptic changes translated to the neuronal targets was not established. Thus, in the present study, immunohistochemistry with a cell-specific marker and the stereological quantification of synapses was used to determine if context-drug learning increases the number of excitatory and inhibitory/modulatory synapses contacting the gamma-aminobutyric acid (GABA) interneurons and/or the pyramidal neurons in the BLA circuitry. Amphetamine-conditioned place preference increased the number of asymmetric (excitatory) synapses contacting the spines and dendrites of pyramidal neurons and the number of multisynaptic boutons contacting pyramidal neurons and GABA interneurons. Context-drug learning increased asymmetric (excitatory) synapses onto dendrites of GABA interneurons and increased symmetric (inhibitory or modulatory) synapses onto dendrites but not perikarya of these same interneurons. The formation of context-drug associations alters the synaptic connectivity in the BLA circuitry, findings that have important implications for drug-seeking behavior.


Assuntos
Complexo Nuclear Basolateral da Amígdala/fisiologia , Condicionamento Psicológico/fisiologia , Espinhas Dendríticas/fisiologia , Células Piramidais/fisiologia , Sinapses/fisiologia , Animais , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Complexo Nuclear Basolateral da Amígdala/ultraestrutura , Estimulantes do Sistema Nervoso Central/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Espinhas Dendríticas/efeitos dos fármacos , Espinhas Dendríticas/ultraestrutura , Dextroanfetamina/farmacologia , Comportamento de Procura de Droga/fisiologia , Imuno-Histoquímica , Interneurônios/efeitos dos fármacos , Interneurônios/fisiologia , Interneurônios/ultraestrutura , Masculino , Microscopia Eletrônica , Inibição Neural/efeitos dos fármacos , Inibição Neural/fisiologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/ultraestrutura , Ratos Sprague-Dawley , Aprendizagem Espacial/efeitos dos fármacos , Aprendizagem Espacial/fisiologia , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura , Ácido gama-Aminobutírico/metabolismo
6.
J Neurosci ; 33(28): 11655-67, 2013 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-23843533

RESUMO

We examined the structural plasticity of excitatory synapses from corticostriatal and thalamostriatal pathways and their postsynaptic targets in adult Sprague-Dawley rats to understand how these striatal circuits change in l-DOPA-induced dyskinesias (LIDs). We present here detailed electron and light microscopic analyses that provide new insight into the nature of the structural and synaptic remodeling of medium spiny neurons in response to LIDs. Numerous studies have implicated enhanced glutamate signaling and persistent long-term potentiation as central to the behavioral sensitization phenomenon of LIDs. Moreover, experience-dependent alterations in behavior are thought to involve structural modifications, specifically alterations in patterns of synaptic connectivity. Thus, we hypothesized that in the striatum of rats with LIDs, one of two major glutamatergic pathways would form new or altered contacts, especially onto the spines of medium spiny neuron (MSNs). Our data provide compelling evidence for a dramatic rewiring of the striatum of dyskinetic rats and that this rewiring involves corticostriatal but not thalamostriatal contacts onto MSNs. There is a dramatic increase in corticostriatal contacts onto spines and dendrites that appear to be directly linked to dyskinetic behaviors, since they were not seen in the striatum of animals that did not develop dyskinesia. There is also an aberrant increase in spines receiving more than one excitatory contact(i.e., multisynaptic spines) in the dyskinetic animals compared with the 6-hydroxydopamine-treated and control rats. Such alterations could substantially impair the ability of striatal neurons to gate cortically driven signals and contribute to the loss of bidirectional synaptic plasticity.


Assuntos
Córtex Cerebral/patologia , Corpo Estriado/patologia , Espinhas Dendríticas/patologia , Discinesia Induzida por Medicamentos/patologia , Sinapses/patologia , Tálamo , Animais , Córtex Cerebral/ultraestrutura , Corpo Estriado/ultraestrutura , Espinhas Dendríticas/ultraestrutura , Levodopa/toxicidade , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Sinapses/ultraestrutura , Tálamo/patologia , Tálamo/ultraestrutura
7.
Res Sq ; 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38585995

RESUMO

Isolation of adult mouse cardiomyocytes is an essential technique for advancing our understanding of cardiac physiology and pathology, and for developing therapeutic strategies to improve cardiac health. Traditionally, cardiomyocytes are isolated from adult mouse hearts using the Langendorff perfusion method in which the heart is excised, cannulated, and retrogradely perfused through the aorta. While this method is highly effective for isolating cardiomyocytes, it requires specialized equipment and technical expertise. To address the challenges of the Langendorff perfusion method, researchers have developed a Langendorff-free technique for isolating cardiomyocytes. This Langendorff-free technique involves anterograde perfusion through the coronary vasculature by clamping the aorta and intraventricular injection. This method simplifies the experimental setup by eliminating the need for specialized equipment and cannulation of the heart. Here, we introduce an updated Langendorff-free method for isolating adult mice cardiomyocytes that builds on the Langendorff-free protocols developed previously. In this method, the aorta is clamped in situ, and the heart is perfused using a peristaltic pump, water bath, and an injection needle. This simplicity makes cardiomyocyte isolation more accessible for researchers who are new to cardiomyocyte isolation or are working with limited resources. In this report, we provide a step-by-step description of our optimized protocol. In addition, we present example studies of analyzing mitochondrial structural and functional characteristics in isolated cardiomyocytes treated with and without the acute inflammatory stimuli lipopolysaccharide (LPS).

8.
Biomedicines ; 11(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37189807

RESUMO

Pathogenic forms of α-synuclein (α-syn) are transferred to and from neurons, astrocytes, and microglia, which spread α-syn pathology in the olfactory bulb and the gut and then throughout the Parkinson's disease (PD) brain and exacerbate neurodegenerative processes. Here, we review attempts to minimize or ameliorate the pathogenic effects of α-syn or deliver therapeutic cargo into the brain. Exosomes (EXs) have several important advantages as carriers of therapeutic agents including an ability to readily cross the blood-brain barrier, the potential for targeted delivery of therapeutic agents, and immune resistance. Diverse cargo can be loaded via various methods, which are reviewed herein, into EXs and delivered into the brain. Genetic modification of EX-producing cells or EXs and chemical modification of EX have emerged as powerful approaches for the targeted delivery of therapeutic agents to treat PD. Thus, EXs hold great promise for the development of next-generation therapeutics for the treatment of PD.

9.
Cell Death Dis ; 14(9): 632, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749127

RESUMO

A severe complication of hematopoietic stem cell transplantation is graft-versus-host disease (GvHD), a reaction that occurs following the transfer of donor immune cells (the graft) into an allogeneic host. Transplanted cells recognize host alloantigens as foreign, resulting in the activation of donor T cells and migration of these pathological cells into host tissues. In this study, we found that caspase-1 is activated in alloreactive murine and human CD4+ and CD8+ T cells early during acute GvHD (aGvHD). The presence of inflammasome-bound active caspase-1 (p33) and ASC-speck formation confirmed inflammasome activation in these cells. We further measured gasdermin D (GSDMD) cleavage and IL-18 secretion from alloreactive T cells ex vivo. Isolated T cells with high levels of active caspase-1 had a strong inflammatory transcriptional signature and a metabolic phenotype similar to inflammatory myeloid cells, including the upregulation of proinflammatory cytokines and metabolic switch from oxidative phosphorylation to aerobic glycolysis. We also observed oxidative stress, mitochondrial dysfunction, and cell death phenotypes consistent with inflammatory cell death in alloreactive T cells. For the first time, this study characterizes caspase-1 activation in transplanted T cells during aGvHD, using mouse and human models, adding to a body of literature supporting inflammasome function in cells of the adaptive immune system.


Assuntos
Linfócitos T CD8-Positivos , Doença Enxerto-Hospedeiro , Humanos , Animais , Camundongos , Inflamassomos , Caspase 1 , Linfócitos T CD4-Positivos
10.
Commun Biol ; 6(1): 16, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609683

RESUMO

Microorganisms living at many sites in the human body compose a complex and dynamic community. Accumulating evidence suggests a significant role for microorganisms in cancer, and therapies that incorporate bacteria have been tried in various types of cancer. We previously demonstrated that cupredoxin azurin secreted by the opportunistic pathogen Pseudomonas aeruginosa, enters human cancer cells and induces apoptotic death1-4. However, the physiological interactions between P. aeruginosa and humans and their role in tumor homeostasis are largely unknown. Here, we show that P. aeruginosa upregulated azurin secretion in response to increasing numbers of and proximity to cancer cells. Conversely, cancer cells upregulated aldolase A secretion in response to increasing proximity to P. aeruginosa, which also correlated with enhanced P. aeruginosa adherence to cancer cells. Additionally, we show that cancer patients had detectable P. aeruginosa and azurin in their tumors and exhibited increased overall survival when they did, and that azurin administration reduced tumor growth in transgenic mice. Our results suggest host-bacterial symbiotic mutualism acting as a diverse adjunct to the host defense system via inter-kingdom communication mediated by the evolutionarily conserved proteins azurin and human aldolase A. This improved understanding of the symbiotic relationship of bacteria with humans indicates the potential contribution to tumor homeostasis.


Assuntos
Azurina , Neoplasias , Camundongos , Animais , Humanos , Azurina/genética , Azurina/metabolismo , Azurina/farmacologia , Pseudomonas aeruginosa/metabolismo , Frutose-Bifosfato Aldolase , Neoplasias/genética , Fenômenos Fisiológicos Celulares
11.
Autophagy ; 18(5): 1020-1048, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34612142

RESUMO

Numerous lines of evidence support the premise that the misfolding and subsequent accumulation of SNCA/α-synuclein (synuclein alpha) is responsible for the underlying neuronal pathology observed in Parkinson disease (PD) and other synucleinopathies. Moreover, the cell-to-cell transfer of these misfolded SNCA species is thought to be responsible for disease progression and the spread of cellular pathology throughout the brain. Previous work has shown that when exogenous, misfolded SNCA fibrils enter cells through endocytosis, they can damage and rupture the membranes of their endocytotic vesicles in which they are trafficked. Rupture of these vesicular membranes exposes intralumenal glycans leading to galectin protein binding, subsequent autophagic protein recruitment, and, ultimately, their introduction into the autophagic-lysosomal pathway. Increasing evidence indicates that both pathological and non-pathological SNCA species undergo autophagy-dependent unconventional secretion. While other proteins have also been shown to be secreted from cells by autophagy, what triggers this release process and how these specific proteins are recruited to a secretory autophagic pathway is largely unknown. Here, we use a human midbrain dopamine (mDA) neuronal culture model to provide evidence in support of a cellular mechanism that explains the cell-to-cell transfer of pathological forms of SNCA that are observed in PD. We demonstrate that LGALS3 (galectin 3) mediates the release of SNCA following vesicular damage. SNCA release is also dependent on TRIM16 (tripartite motif containing 16) and ATG16L1 (autophagy related 16 like 1), providing evidence that secretion of SNCA is mediated by an autophagic secretory pathway.


Assuntos
Neurônios Dopaminérgicos , Galectina 3 , Doença de Parkinson , alfa-Sinucleína , Autofagia/fisiologia , Proteínas Sanguíneas , Neurônios Dopaminérgicos/metabolismo , Galectina 3/metabolismo , Galectinas , Humanos , Lisossomos/metabolismo , Mesencéfalo/metabolismo , Doença de Parkinson/metabolismo , Proteínas com Motivo Tripartido/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , alfa-Sinucleína/metabolismo
12.
Pharmaceutics ; 14(7)2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35890267

RESUMO

Malaria elimination urgently needs novel antimalarial therapies that transcend resistance, toxicity, and high costs. Our multicentric international collaborative team focuses on developing multistage antimalarials that exhibit novel mechanisms of action. Here, we describe the design, synthesis, and evaluation of a novel multistage antimalarial compound, 'Calxinin'. A compound that consists of hydroxyethylamine (HEA) and trifluoromethyl-benzyl-piperazine. Calxinin exhibits potent inhibitory activity in the nanomolar range against the asexual blood stages of drug-sensitive (3D7), multidrug-resistant (Dd2), artemisinin-resistant (IPC4912), and fresh Kenyan field isolated Plasmodium falciparum strains. Calxinin treatment resulted in diminished maturation of parasite sexual precursor cells (gametocytes) accompanied by distorted parasite morphology. Further, in vitro liver-stage testing with a mouse model showed reduced parasite load at an IC50 of 79 nM. A single dose (10 mg/kg) of Calxinin resulted in a 30% reduction in parasitemia in mice infected with a chloroquine-resistant strain of the rodent parasite P. berghei. The ex vivo ookinete inhibitory concentration within mosquito gut IC50 was 150 nM. Cellular in vitro toxicity assays in the primary and immortalized human cell lines did not show cytotoxicity. A computational protein target identification pipeline identified a putative P. falciparum membrane protein (Pf3D7_1313500) involved in parasite calcium (Ca2+) homeostasis as a potential Calxinin target. This highly conserved protein is related to the family of transient receptor potential cation channels (TRP-ML). Target validation experiments showed that exposure of parasitized RBCs (pRBCs) to Calxinin induces a rapid release of intracellular Ca2+ from pRBCs; leaving de-calcinated parasites trapped in RBCs. Overall, we demonstrated that Calxinin is a promising antimalarial lead compound with a novel mechanism of action and with potential therapeutic, prophylactic, and transmission-blocking properties against parasites resistant to current antimalarials.

13.
J Neurosci ; 30(13): 4676-86, 2010 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-20357118

RESUMO

Drug seeking and the vulnerability to relapse occur when individuals are exposed to an environment with sensory cues in which drug taking has occurred. Memory formation is thought to require plasticity in synaptic circuits, and so we examined whether the memory for a drug-paired environment correlates with changes in the synaptic circuits of the basolateral amygdala (BLA), in which emotional learning is a recognized phenomenon. We used amphetamine (AMPH) as the unconditioned stimulus in the conditioned place preference (CPP) paradigm. Rats were conditioned with 1.0 mg/kg AMPH and tested, drug free, 72 h after the last conditioning session. Controls included a saline-conditioned group and a home cage AMPH injection group, whose exposure to the CPP apparatus was delayed by 4 h, long enough to clear the AMPH from the brain. We counted excitatory synapses in the BLA using the electron microscope and the physical disector design (stereology). Rats that expressed AMPH CPP had an increase in excitatory synapses compared with controls. Excitatory synaptic activity was measured using in vivo intracellular recordings from the BLA in anesthetized rats. We found that AMPH CPP, but not drug alone, increased measures of synaptic drive, including the frequency of synaptic events, and the paired-pulse ratio of synaptic inputs to BLA pyramidal neurons. The in vivo findings suggest that the increase in BLA neuronal excitatory drive reflects the change in excitatory synapse number. Thus, context-drug associations are accompanied by structural and functional plasticity in the BLA, findings that have important implications for drug-seeking behavior.


Assuntos
Anfetamina/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Aprendizagem por Associação , Neurônios/efeitos dos fármacos , Tonsila do Cerebelo/fisiologia , Tonsila do Cerebelo/ultraestrutura , Animais , Condicionamento Clássico/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores , Masculino , Plasticidade Neuronal , Neurônios/fisiologia , Neurônios/ultraestrutura , Ratos , Ratos Sprague-Dawley , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
14.
Metabolism ; 102: 153990, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666192

RESUMO

OBJECTIVE: Rates of overweight and obesity epidemic have risen significantly in the past few decades, and 34% of adults and 15-20% of children and adolescents in the United States are now obese. Melanocortin receptor 4 (MC4R), contributes to appetite control in hypothalamic neurons and is a target for future anti-obesity treatments (such as setmelanotide) or novel drug development effort. Proper MC4R trafficking regulation in hypothalamic neurons is crucial for normal neural control of homeostasis and is altered in obesity and in presence of lipids. The mechanisms underlying altered MC4R trafficking in the context of obesity is still unclear. Here, we discovered that C2CD5 expressed in the hypothalamus is involved in the regulation of MC4R endocytosis. This study unmasked a novel trafficking protein nutritionally regulated in the hypothalamus providing a novel target for MC4R dependent pathways involved in bodyweight homeostasis and Obesity. METHODS: To evaluate the expression of C2cd5, we first used in situ hybridization and RNAscope technology in combination with electronic microscopy. For in vivo, we characterized the energy balance of wild type (WT) and C2CD5 whole-body knockout (C2CD5KO) mice fed normal chow (NC) and/or western-diet (high-fat/high-sucrose/cholesterol) (WD). To this end, we performed comprehensive longitudinal assessment of bodyweight, energy balance (food intake, energy expenditure, locomotor activity using TSE metabolic cages), and glucose homeostasis. In addition, we evaluated the consequence of loss of C2CD5 on feeding behavior changes normally induced by MC4R agonist (Melanotan, MTII) injection in the paraventricular hypothalamus (PVH). For in vitro approach, we tease out the role of C2CD5 and its calcium sensing domain C2 in MC4R trafficking. We focused on endocytosis of MC4R using an antibody feeding experiment (in a neuronal cell line - Neuro2A (N2A) stably expressing HA-MC4R-GFP; against HA-tag and analyzed by flux cytometry). RESULTS: We found that 1) the expression of hypothalamic C2CD5 is decreased in diet-induced obesity models compared to controls, 2) mice lacking C2CD5 exhibit an increase in food intake compared to WT mice, 3) C2CD5 interacts with endocytosis machinery in hypothalamus, 4) loss of functional C2CD5 (lacking C2 domain) blunts MC4R endocytosis in vitro and increases MC4R at the surface that fails to respond to MC4R ligand, and, 5) C2CD5KO mice exhibit decreased acute responses to MTII injection into the PVH. CONCLUSIONS: Based on these, we conclude that hypothalamic C2CD5 is involved in MC4R endocytosis and regulate bodyweight homeostasis. These studies suggest that C2CD5 represents a new protein regulated by metabolic cues and involved in metabolic receptor endocytosis. C2CD5 represent a new target and pathway that could be targeted in Obesity.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Metabolismo Energético/genética , Hipotálamo/metabolismo , Proteínas de Membrana/metabolismo , Receptor Tipo 4 de Melanocortina/metabolismo , Animais , Peso Corporal/genética , Proteínas de Ligação ao Cálcio/genética , Células Cultivadas , Comportamento Alimentar/fisiologia , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Associadas aos Microtúbulos/fisiologia , Obesidade/genética , Obesidade/metabolismo , Obesidade/fisiopatologia , Transporte Proteico/genética
15.
J Extracell Vesicles ; 9(1): 1789326, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32944176

RESUMO

Extracellular vesicles (EVs) have been implicated in a wide variety of biological activities, have been implicated in the pathogenesis of numerous diseases, and have been proposed to serve as potential biomarkers of disease in human patients and animal models. However, characterization of EV populations is often performed using methods that do not account for the heterogeneity of EV populations and require comparatively large sample sizes to facilitate analysis. Here, we describe an imaging-based method that allows for the multiplexed characterization of EV populations at the single EV level following centrifugation of EV populations directly onto cover slips, allowing comprehensive analysis of EV populations with relatively small samples. We observe that canonical EV markers are present on subsets of EVs which differ substantially in a producer cell and cargo specific fashion, including differences in EVs containing different HIV-1 proteins previously reported to be incorporated into pathogenic EVs. We also describe a lectin binding assay to interrogate EVs based on their glycan content, which we observe to change in response to pharmacological modulation of secretory autophagy pathways. These studies collectively reveal that a multiplexed analysis of EV populations using fluorescent microscopy can reveal differences in specific EV populations that may be used to understand the biogenesis of specific EV populations and/or to interrogate small subsets of EVs of interest within larger EV populations in biological samples.

16.
Synapse ; 63(2): 126-35, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19016489

RESUMO

Psychostimulant drug experience leads not only to long-lasting changes in behavior but also modifications in the activity and morphology of pyramidal neurons in the medial prefrontal cortex (mPFC). The objective of this study was to establish whether repeated treatment of rats with amphetamine (AMPH) is accompanied by changes in the pattern or types of synapses in the mPFC and, specifically, onto neurons that project to the lateral hypothalamus, where our earlier work has shown increased markers of neuronal activity after repeated AMPH treatment (Morshedi and Meredith [2008] Psychopharmacology (Berl) 197:179-189). Rats were treated with a behaviorally sensitizing regimen of AMPH, following which synapses in the infralimbic and prelimbic cortices of the mPFC, were analyzed with unbiased stereology (physical disector and electron microscopy). All synapses were counted and their targets were identified by standard methodological criteria. Repeated AMPH administration was associated with a significant increase in the number of asymmetric axospinous synapses, no change in axodendritic or axosomatic contacts, and no change in the total number of synapses on corticolateral hypothalamic pyramidal neurons compared to vehicle-treated rats. Therefore, behavioral sensitization as a result of repeated exposure to AMPH is accompanied by the increased formation of spine, but not dendritic, synapses onto pyramidal neurons in the mPFC.


Assuntos
Anfetamina/toxicidade , Estimulantes do Sistema Nervoso Central/toxicidade , Córtex Pré-Frontal/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Sinapses/ultraestrutura , Animais , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Córtex Pré-Frontal/ultraestrutura , Ratos , Ratos Sprague-Dawley
17.
J Vis Exp ; (145)2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30985747

RESUMO

Fluorescence recovery after photobleaching (FRAP) is a microscopy technique that can be used to quantify protein mobility in live cells. In a typical FRAP experiment, steady-state fluorescence is observed by repeated imaging with low-intensity laser light. Subsequently, the fluorescent molecules are rapidly and irreversibly impaired via brief exposure to high-intensity laser light. Information about protein mobility is obtained by monitoring the recovery of fluorescence. We used FRAP to determine the mobility of p62 in aggresome-like induced structures (ALIS) in murine macrophages after stimulation with lipopolysaccharide (LPS). Because many existing FRAP protocols are either incomplete or complex, our goal was to provide a comprehensive, practical, and straightforward step-by-step protocol for FRAP experiments with live cells. Here, we describe RAW264.7 macrophage transfection with yellow fluorescent protein-p62 (YFP-p62), induction of ALIS by exposing the cells to LPS, and a step-by-step method for collecting prebleach and postbleach FRAP images and data analysis. Finally, we discuss important factors to consider when conducting a FRAP experiment.


Assuntos
Recuperação de Fluorescência Após Fotodegradação/métodos , Agregados Proteicos , Proteína Sequestossoma-1/química , Proteína Sequestossoma-1/metabolismo , Animais , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Células RAW 264.7
18.
Neuropharmacology ; 54(1): 108-16, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17675104

RESUMO

Endocannabinoid signaling has been implicated in habituation to repeated stress. The hypothesis that repeated exposures to stress alters endocannabinoid signaling in the limbic circuit was tested by restraining male mice for 30 min/day for 1, 7, or 10 days and measuring brain endocannabinoid content. Amygdalar N-arachidonylethanolamine was decreased after 1, 7, and 10 restraint episodes; 2-arachidonylglycerol was increased after the 10th restraint. A similar pattern occurred in the medial prefrontal cortex (mPFC): N-arachidonylethanolamine was decreased after the 7th and 10th restraints and 2-arachidonylglycerol was increased after the 10th restraint. In the ventral striatum, the pattern reversed: N-arachidonylethanolamine was increased after the 10th restraint and 2-arachidonylglycerol was decreased after the 7th restraint. Palmitoylethanolamide contents changed in parallel with N-arachidonylethanolamine in the amygdala and ventral striatum. A single restraint episode did not affect the activity of fatty acid amide hydrolase (FAAH) in any of the brain regions examined. After the 10th restraint, both V(max) and K(m) for N-arachidonylethanolamine were increased in the mPFC; while only the V(max) was increased in the amygdala. On the other hand, the V(max) of FAAH was decreased in ventral striatum after the 10th restraint. After the 10th restraint, the maximum velocity for 2-oleoylglycerol hydrolysis was increased in mPFC; no other changes in 2-oleoylglycerol hydrolysis occurred. Repeated exposure to restraint produced no changes in CB(1) receptor density in any of the areas examined. These studies are consistent with the hypothesis that stress exposure alters endocannabinoid signaling in the brain and that alterations in endocannabinoid signaling occur during habituation to stress.


Assuntos
Tonsila do Cerebelo/metabolismo , Moduladores de Receptores de Canabinoides/metabolismo , Corpo Estriado/metabolismo , Endocanabinoides , Córtex Pré-Frontal/metabolismo , Estresse Psicológico/patologia , Amidoidrolases/metabolismo , Análise de Variância , Animais , Corticosterona/sangue , Cicloexanóis/farmacocinética , Ensaio de Imunoadsorção Enzimática/métodos , Glicerídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Restrição Física/métodos , Estresse Psicológico/etiologia , Estresse Psicológico/metabolismo , Fatores de Tempo , Trítio/farmacocinética
19.
Prog Neuropsychopharmacol Biol Psychiatry ; 31(3): 633-41, 2007 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-17258369

RESUMO

Since endocannabinoids modulate reward processing and the stress response, we tested the hypothesis that endocannabinoids regulate stress-induced decreased sensitivity to natural reward. Restraint was used to produce stress-induced reductions in sucrose consumption and preference in male mice. Central cannabinoid receptor (CB(1)) signaling was modulated pharmacologically prior to the application of stress. The preference for sucrose over water was significantly decreased in mice exposed to restraint. Treatment of mice with a cannabinoid receptor agonist (CP55940) or fatty acid amide hydrolase inhibitor (URB597) attenuated, while the CB(1) receptor antagonist/inverse agonist, rimonabant (SR141716), enhanced, stress-induced decreases in sucrose preference. These data are consistent with a tonically active, stress-inhibitory role for the CB(1) receptor. Mice treated with 10 daily episodes of restraint showed reduced sucrose preference that was unaffected by CP55940 and URB597. However, rimonabant produced a greater reduction in sucrose preference on day 10 compared to day 1. These data suggest that on day 10, endocannabinoid signaling is maximally activated and essential for reward sensitivity. The findings of the present study indicate that the CB(1)/endocannabinoid signaling system is an important allostatic mediator that both modulates the responses of mice to stress and is itself modulated by stress.


Assuntos
Moduladores de Receptores de Canabinoides/fisiologia , Endocanabinoides , Preferências Alimentares/fisiologia , Recompensa , Estresse Psicológico/fisiopatologia , Análise de Variância , Animais , Comportamento Animal , Benzamidas/farmacologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Carbamatos/farmacologia , Cicloexanos/farmacologia , Cicloexanóis , Relação Dose-Resposta a Droga , Comportamento de Ingestão de Líquido/efeitos dos fármacos , Interações Medicamentosas , Privação de Alimentos , Preferências Alimentares/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Fenóis/farmacologia , Piperidinas/farmacologia , Pirazóis/farmacologia , Restrição Física/efeitos adversos , Rimonabanto , Sacarose/administração & dosagem , Fatores de Tempo , Privação de Água/fisiologia
20.
J Behav Addict ; 6(1): 84-91, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28316252

RESUMO

Background and aims Smartphones are ubiquitous. As smartphones increased in popularity, researchers realized that people were becoming dependent on their smartphones. The purpose here was to provide a better understanding of the factors related to problematic smartphone use (PSPU). Methods The participants were 100 undergraduates (25 males, 75 females) whose ages ranged from 18 to 23 (mean age = 20 years). The participants completed questionnaires to assess gender, ethnicity, year in college, father's education level, mother's education level, family income, age, family history of alcoholism, and PSPU. The Family Tree Questionnaire assessed family history of alcoholism. The Mobile Phone Problem Use Scale (MPPUS) and the Adapted Cell Phone Addiction Test (ACPAT) were used to determine the degree of PSPU. Whereas the MPPUS measures tolerance, escape from other problems, withdrawal, craving, and negative life consequences, the ACPAT measures preoccupation (salience), excessive use, neglecting work, anticipation, lack of control, and neglecting social life. Results Family history of alcoholism and father's education level together explained 26% of the variance in the MPPUS scores and 25% of the variance in the ACPAT scores. The inclusion of mother's education level, ethnicity, family income, age, year in college, and gender did not significantly increase the proportion of variance explained for either MPPUS or ACPAT scores. Discussion and conclusions Family history of alcoholism and father's education level are good predictors of PSPU. As 74%-75% of the variance in PSPU scale scores was not explained, future studies should aim to explain this variance.


Assuntos
Alcoolismo , Comportamento Aditivo/epidemiologia , Smartphone , Adolescente , Alcoolismo/epidemiologia , Escolaridade , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pais , Escalas de Graduação Psiquiátrica , Análise de Regressão , Estudantes , Inquéritos e Questionários , Universidades , Adulto Jovem
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