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1.
J Neurosci ; 44(23)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38719446

RESUMO

Drugs of abuse cause changes in the prefrontal cortex (PFC) and associated regions that impair inhibitory control over drug-seeking. Breaking the contingencies between drug-associated cues and the delivery of the reward during extinction learning reduces relapse. Vagus nerve stimulation (VNS) has previously been shown to enhance extinction learning and reduce drug-seeking. Here we determined the effects of VNS-mediated release of brain-derived neurotrophic factor (BDNF) on extinction and cue-induced reinstatement in male rats trained to self-administer cocaine. Pairing 10 d of extinction training with VNS facilitated extinction and reduced drug-seeking behavior during reinstatement. Rats that received a single extinction session with VNS showed elevated BDNF levels in the medial PFC as determined via an enzyme-linked immunosorbent assay. Systemic blockade of tropomyosin receptor kinase B (TrkB) receptors during extinction, via the TrkB antagonist ANA-12, decreased the effects of VNS on extinction and reinstatement. Whole-cell recordings in brain slices showed that cocaine self-administration induced alterations in the ratio of AMPA and NMDA receptor-mediated currents in Layer 5 pyramidal neurons of the infralimbic cortex (IL). Pairing extinction with VNS reversed cocaine-induced changes in glutamatergic transmission by enhancing AMPAR currents, and this effect was blocked by ANA-12. Our study suggests that VNS consolidates the extinction of drug-seeking behavior by reversing drug-induced changes in synaptic AMPA receptors in the IL, and this effect is abolished by blocking TrkB receptors during extinction, highlighting a potential mechanism for the therapeutic effects of VNS in addiction.


Assuntos
Comportamento de Procura de Droga , Extinção Psicológica , Plasticidade Neuronal , Córtex Pré-Frontal , Ratos Sprague-Dawley , Receptor trkB , Estimulação do Nervo Vago , Animais , Masculino , Ratos , Estimulação do Nervo Vago/métodos , Comportamento de Procura de Droga/fisiologia , Comportamento de Procura de Droga/efeitos dos fármacos , Receptor trkB/metabolismo , Receptor trkB/antagonistas & inibidores , Plasticidade Neuronal/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Extinção Psicológica/fisiologia , Extinção Psicológica/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Autoadministração , Cocaína/farmacologia , Cocaína/administração & dosagem
2.
Am J Physiol Renal Physiol ; 326(4): F644-F660, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38420674

RESUMO

Patients with hypertension or obesity can develop glomerular dysfunction characterized by injury and depletion of podocytes. To better understand the molecular processes involved, young mice were treated with either deoxycorticosterone acetate (DOCA) or fed a high-fat diet (HFD) to induce hypertension or obesity, respectively. The transcriptional changes associated with these phenotypes were measured by unbiased bulk mRNA sequencing of isolated podocytes from experimental models and their respective controls. Key findings were validated by immunostaining. In addition to a decrease in canonical proteins and reduced podocyte number, podocytes from both hypertensive and obese mice exhibited a sterile inflammatory phenotype characterized by increases in NLR family pyrin domain containing 3 (NLRP3) inflammasome, protein cell death-1, and Toll-like receptor pathways. Finally, although the mice were young, podocytes in both models exhibited increased expression of senescence and aging genes, including genes consistent with a senescence-associated secretory phenotype. However, there were differences between the hypertension- and obesity-associated senescence phenotypes. Both show stress-induced podocyte senescence characterized by increased p21 and p53. Moreover, in hypertensive mice, this is superimposed upon age-associated podocyte senescence characterized by increased p16 and p19. These results suggest that senescence, aging, and inflammation are critical aspects of the podocyte phenotype in experimental hypertension and obesity in mice.NEW & NOTEWORTHY Hypertension and obesity can lead to glomerular dysfunction in patients, causing podocyte injury and depletion. Here, young mice given deoxycorticosterone acetate or a high-fat diet to induce hypertension or obesity, respectively. mRNA sequencing of isolated podocytes showed transcriptional changes consistent with senescence, a senescent-associated secretory phenotype, and aging, which was confirmed by immunostaining. Ongoing studies are determining the mechanistic roles of the accelerated aging podocyte phenotype in experimental hypertension and obesity.


Assuntos
Hipertensão , Nefropatias , Podócitos , Humanos , Camundongos , Animais , Idoso , Podócitos/metabolismo , Camundongos Obesos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Fenótipo , Nefropatias/metabolismo , Obesidade/metabolismo , Hipertensão/genética , Hipertensão/metabolismo , Desoxicorticosterona , Acetatos/metabolismo , RNA Mensageiro/metabolismo
3.
Am J Physiol Renal Physiol ; 326(1): F120-F134, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37855038

RESUMO

As life expectancy continues to rise, age-related diseases are becoming more prevalent. For example, proteinuric glomerular diseases typified by podocyte injury have worse outcomes in the elderly compared with young patients. However, the reasons are not well understood. We hypothesized that injury to nonaged podocytes induces senescence, which in turn augments their aging processes. In primary cultured human podocytes, injury induced by a cytopathic antipodocyte antibody, adriamycin, or puromycin aminonucleoside increased the senescence-related genes CDKN2A (p16INK4a/p14ARF), CDKN2D (p19INK4d), and CDKN1A (p21). Podocyte injury in human kidney organoids was accompanied by increased expression of CDKN2A, CDKN2D, and CDKN1A. In young mice, experimental focal segmental glomerulosclerosis (FSGS) induced by adriamycin and antipodocyte antibody increased the glomerular expression of p16, p21, and senescence-associated ß-galactosidase (SA-ß-gal). To assess the long-term effects of early podocyte injury-induced senescence, we temporally followed young mice with experimental FSGS through adulthood (12 m of age) and middle age (18 m of age). p16 and Sudan black staining were higher at middle age in mice with earlier FSGS compared with age-matched mice that did not get FSGS when young. This was accompanied by lower podocyte density, reduced canonical podocyte protein expression, and increased glomerular scarring. These results are consistent with injury-induced senescence in young podocytes, leading to increased senescence of podocytes by middle age accompanied by lower podocyte lifespan and health span.NEW & NOTEWORTHY Glomerular function is decreased by aging. However, little is known about the molecular mechanisms involved in age-related glomerular changes and which factors could contribute to a worse glomerular aging process. Here, we reported that podocyte injury in young mice and culture podocytes induced senescence, a marker of aging, and accelerates glomerular aging when compared with healthy aging mice.


Assuntos
Glomerulosclerose Segmentar e Focal , Nefropatias , Podócitos , Pessoa de Meia-Idade , Humanos , Camundongos , Animais , Idoso , Podócitos/metabolismo , Glomerulosclerose Segmentar e Focal/metabolismo , Glomérulos Renais/metabolismo , Nefropatias/metabolismo , Envelhecimento , Doxorrubicina/toxicidade , Doxorrubicina/metabolismo
4.
Psychol Res ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896309

RESUMO

It is widely believed that people can distinguish between many odors although there is limited empirical evidence. Odor discrimination tasks are employed much less often than other measures of olfaction, but, interestingly, performance is typically ~ 75% correct. This less-than-perfect performance is rarely highlighted, although it suggests that people may not be as good at discriminating odors as is commonly believed. Odor discrimination is understudied in children, and although available evidence suggests that it improves with age, children perform better when the task is simpler. In the present study, we explored odor discrimination in children and young adults with a relatively simple same-different task using common and uncommon odors. We found that children perform as well as young adults, but that overall performance was less than perfect and depended on the odors to be discriminated. We found evidence that ability to discriminate between odors improves as the difference in pleasantness of the odors increases. In a second experiment, we tested this directly by exploring whether odors that differ in pleasantness and edibility, two dimensions that appear to be important in olfactory perception, are easier to discriminate than odors that are the same on those dimensions. We found further evidence that odors that differ in pleasantness are easier to discriminate.

5.
Semin Liver Dis ; 43(4): 460-471, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37967885

RESUMO

The liver's unique chromosomal variations, including polyploidy and aneuploidy, influence hepatocyte identity and function. Among the most well-studied mammalian polyploid cells, hepatocytes exhibit a dynamic interplay between diploid and polyploid states. The ploidy state is dynamic as hepatocytes move through the "ploidy conveyor," undergoing ploidy reversal and re-polyploidization during proliferation. Both diploid and polyploid hepatocytes actively contribute to proliferation, with diploids demonstrating an enhanced proliferative capacity. This enhanced potential positions diploid hepatocytes as primary drivers of liver proliferation in multiple contexts, including homeostasis, regeneration and repopulation, compensatory proliferation following injury, and oncogenic proliferation. This review discusses the influence of ploidy variations on cellular activity. It presents a model for ploidy-associated hepatocyte proliferation, offering a deeper understanding of liver health and disease with the potential to uncover novel treatment approaches.


Assuntos
Regeneração Hepática , Fígado , Animais , Humanos , Regeneração Hepática/genética , Hepatócitos , Proliferação de Células , Poliploidia , Mamíferos
6.
Clin Infect Dis ; 76(12): 2047-2055, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-36806551

RESUMO

BACKGROUND: Guidelines emphasize rapid antibiotic treatment for sepsis, but infection presence is often uncertain at initial presentation. We investigated the incidence and drivers of false-positive presumptive infection diagnosis among emergency department (ED) patients meeting Sepsis-3 criteria. METHODS: For a retrospective cohort of patients hospitalized after meeting Sepsis-3 criteria (acute organ failure and suspected infection including blood cultures drawn and intravenous antimicrobials administered) in 1 of 4 EDs from 2013 to 2017, trained reviewers first identified the ED-diagnosed source of infection and adjudicated the presence and source of infection on final assessment. Reviewers subsequently adjudicated final infection probability for a randomly selected 10% subset of subjects. Risk factors for false-positive infection diagnosis and its association with 30-day mortality were evaluated using multivariable regression. RESULTS: Of 8267 patients meeting Sepsis-3 criteria in the ED, 699 (8.5%) did not have an infection on final adjudication and 1488 (18.0%) patients with confirmed infections had a different source of infection diagnosed in the ED versus final adjudication (ie, initial/final source diagnosis discordance). Among the subset of patients whose final infection probability was adjudicated (n = 812), 79 (9.7%) had only "possible" infection and 77 (9.5%) were not infected. Factors associated with false-positive infection diagnosis included hypothermia, altered mental status, comorbidity burden, and an "unknown infection source" diagnosis in the ED (odds ratio: 6.39; 95% confidence interval: 5.14-7.94). False-positive infection diagnosis was not associated with 30-day mortality. CONCLUSIONS: In this large multihospital study, <20% of ED patients meeting Sepsis-3 criteria had no infection or only possible infection on retrospective adjudication.


Assuntos
Sepse , Humanos , Estudos Retrospectivos , Serviço Hospitalar de Emergência , Mortalidade Hospitalar
7.
Am J Physiol Lung Cell Mol Physiol ; 324(2): L141-L153, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36511516

RESUMO

Obesity is associated with severe, difficult-to-control asthma, and increased airway oxidative stress. Mitochondrial reactive oxygen species (mROS) are an important source of oxidative stress in asthma, leading us to hypothesize that targeting mROS in obese allergic asthma might be an effective treatment. Using a mouse model of house dust mite (HDM)-induced allergic airway disease in mice fed a low- (LFD) or high-fat diet (HFD), and the mitochondrial antioxidant MitoQuinone (MitoQ), we investigated the effects of obesity and ROS on HDM-induced airway inflammation, remodeling, and airway hyperresponsiveness (AHR). Obese allergic mice showed increased lung tissue eotaxin, airway tissue eosinophilia, and AHR compared with lean allergic mice. MitoQ reduced airway inflammation, remodeling, and hyperreactivity in both lean and obese allergic mice, and tissue eosinophilia in obese-allergic mice. Similar effects were observed with decyl triphosphonium (dTPP+), the hydrophobic cationic moiety of MitoQ lacking ubiquinone. HDM-induced oxidative sulfenylation of proteins was increased particularly in HFD mice. Although only MitoQ reduced sulfenylation of proteins involved in protein folding in the endoplasmic reticulum (ER), ER stress was attenuated by both MitoQ and dTPP+ suggesting the anti-allergic effects of MitoQ are mediated in part by effects of its hydrophobic dTPP+ moiety reducing ER stress. In summary, oxidative signaling is an important mediator of allergic airway disease. MitoQ, likely through reducing protein oxidation and affecting the UPR pathway, might be effective for the treatment of asthma and specific features of obese asthma.


Assuntos
Asma , Eosinofilia , Animais , Asma/metabolismo , Pulmão/metabolismo , Obesidade/metabolismo , Inflamação/patologia , Pyroglyphidae , Eosinofilia/patologia , Modelos Animais de Doenças
8.
Am J Pathol ; 192(9): 1259-1281, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35718058

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is an epidemic affecting 30% of the US population. It is characterized by insulin resistance, and by defective lipid metabolism and mitochondrial dysfunction in the liver. SLC25A34 is a major repressive target of miR-122, a miR that has a central role in NAFLD and liver cancer. However, little is known about the function of SLC25A34. To investigate SLC25A34 in vitro, mitochondrial respiration and bioenergetics were examined using hepatocytes depleted of Slc25a34 or overexpressing Slc25a34. To test the function of SLC25A34 in vivo, a hepatocyte-specific knockout mouse was generated, and loss of SLC25A34 was assessed in mice maintained on a chow diet and a fast-food diet (FFD), a model for NAFLD. Hepatocytes depleted of Slc25a34 displayed increased mitochondrial biogenesis, lipid synthesis, and ADP/ATP ratio; Slc25a34 overexpression had the opposite effect. In the knockout model on chow diet, SLC25A34 loss modestly affected liver function (altered glucose metabolism was the most pronounced defect). RNA-sequencing revealed changes in metabolic processes, especially fatty acid metabolism. After 2 months on FFD, knockouts had a more severe phenotype, with increased lipid content and impaired glucose tolerance, which was attenuated after longer FFD feeding (6 months). This work thus presents a novel model for studying SLC25A34 in vivo in which SLC25A34 plays a role in mitochondrial respiration and bioenergetics during NAFLD.


Assuntos
MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Dieta Hiperlipídica , Glucose/metabolismo , Hepatócitos/metabolismo , Homeostase , Metabolismo dos Lipídeos , Lipídeos , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo
9.
Environ Sci Technol ; 57(10): 4082-4090, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36848936

RESUMO

An increasing percentage of US waste methane (CH4) emissions come from wastewater treatment (10% in 1990 to 14% in 2019), although there are limited measurements across the sector, leading to large uncertainties in current inventories. We conducted the largest study of CH4 emissions from US wastewater treatment, measuring 63 plants with average daily flows ranging from 4.2 × 10-4 to 8.5 m3 s-1 (<0.1 to 193 MGD), totaling 2% of the 62.5 billion gallons treated, nationally. We employed Bayesian inference to quantify facility-integrated emission rates with a mobile laboratory approach (1165 cross-plume transects). The median plant-averaged emission rate was 1.1 g CH4 s-1 (0.1-21.6 g CH4 s-1; 10th/90th percentiles; mean 7.9 g CH4 s-1), and the median emission factor was 3.4 × 10-2 g CH4 (g influent 5 day biochemical oxygen demand; BOD5)-1 [0.6-9.9 × 10-2 g CH4 (g BOD5)-1; 10th/90th percentiles; mean 5.7 × 10-2 g CH4 (g BOD5)-1]. Using a Monte Carlo-based scaling of measured emission factors, emissions from US centrally treated domestic wastewater are 1.9 (95% CI: 1.5-2.4) times greater than the current US EPA inventory (bias of 5.4 MMT CO2-eq). With increasing urbanization and centralized treatment, efforts to identify and mitigate CH4 emissions are needed.


Assuntos
Metano , Purificação da Água , Estados Unidos , Teorema de Bayes , Águas Residuárias , Óxido Nitroso/análise
10.
Thorax ; 77(7): 669-678, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34400514

RESUMO

BACKGROUND: The role of club cells in the pathology of idiopathic pulmonary fibrosis (IPF) is not well understood. Protein disulfide isomerase A3 (PDIA3), an endoplasmic reticulum-based redox chaperone required for the functions of various fibrosis-related proteins; however, the mechanisms of action of PDIA3 in pulmonary fibrosis are not fully elucidated. OBJECTIVES: To examine the role of club cells and PDIA3 in the pathology of pulmonary fibrosis and the therapeutic potential of inhibition of PDIA3 in lung fibrosis. METHODS: Role of PDIA3 and aberrant club cells in lung fibrosis was studied by analyses of human transcriptome dataset from Lung Genomics Research Consortium, other public resources, the specific deletion or inhibition of PDIA3 in club cells and blocking SPP1 downstream of PDIA3 in mice. RESULTS: PDIA3 and club cell secretory protein (SCGB1A1) signatures are upregulated in IPF compared with control patients. PDIA3 or SCGB1A1 increases also correlate with a decrease in lung function in patients with IPF. The bleomycin (BLM) model of lung fibrosis showed increases in PDIA3 in SCGB1A1 cells in the lung parenchyma. Ablation of Pdia3, specifically in SCGB1A1 cells, decreases parenchymal SCGB1A1 cells along with fibrosis in mice. The administration of a PDI inhibitor LOC14 reversed the BLM-induced parenchymal SCGB1A1 cells and fibrosis in mice. Evaluation of PDIA3 partners revealed that SPP1 is a major interactor in fibrosis. Blocking SPP1 attenuated the development of lung fibrosis in mice. CONCLUSIONS: Our study reveals a new relationship with distally localised club cells, PDIA3 and SPP1 in lung fibrosis and inhibition of PDIA3 or SPP1 attenuates lung fibrosis.


Assuntos
Fibrose Pulmonar Idiopática , Isomerases de Dissulfetos de Proteínas/metabolismo , Animais , Bleomicina , Células Epiteliais/metabolismo , Humanos , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/patologia , Camundongos , Osteopontina/genética , Osteopontina/metabolismo , Isomerases de Dissulfetos de Proteínas/genética
11.
Int J Mol Sci ; 23(3)2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35162999

RESUMO

Influenza (IAV) neuraminidase (NA) is a glycoprotein required for the viral exit from the cell. NA requires disulfide bonds for proper function. We have recently demonstrated that protein disulfide isomerase (PDI)A3 is required for oxidative folding of IAV hemagglutinin (HA), and viral propagation. However, it not known whether PDIs are required for NA maturation or if these interactions represent a putative target for the treatment of influenza infection. We sought to determine whether PDIA3 is required for disulfide bonds of NA, its activity, and propagation of the virus. Requirement of disulfides for NA oligomerization and activity were determined using biotin switch and redox assays in WT and PDIA3-/- in A549 cells. A PDI specific inhibitor (LOC14) was utilized to determine the requirement of PDIs in NA activity, IAV burden, and inflammatory response in A549 and primary mouse tracheal epithelial cells. Mice were treated with the inhibitor LOC14 and subsequently examined for IAV burden, NA activity, cytokine, and immune response. IAV-NA interacts with PDIA3 and this interaction is required for NA activity. PDIA3 ablation or inhibition decreased NA activity, viral burden, and inflammatory response in lung epithelial cells. LOC14 treatment significantly attenuated the influenza-induced inflammatory response in mice including the overall viral burden. These results provide evidence for PDIA3 inhibition suppressing NA activity, potentially providing a novel platform for host-targeted antiviral therapies.


Assuntos
Inibidores Enzimáticos/administração & dosagem , Vírus da Influenza A Subtipo H1N1/enzimologia , Neuraminidase/metabolismo , Infecções por Orthomyxoviridae/tratamento farmacológico , Isomerases de Dissulfetos de Proteínas/metabolismo , Proteínas Virais/metabolismo , Células A549 , Animais , Células Cultivadas , Modelos Animais de Doenças , Cães , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Células Madin Darby de Rim Canino , Camundongos , Neuraminidase/química , Infecções por Orthomyxoviridae/metabolismo , Cultura Primária de Células , Dobramento de Proteína , Traqueia/citologia , Traqueia/efeitos dos fármacos , Traqueia/metabolismo , Traqueia/virologia , Proteínas Virais/química
12.
J Am Chem Soc ; 143(40): 16610-16620, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34586787

RESUMO

The capacity of X-ray photoelectron spectroscopy (XPS) to provide information on the electronic structure of molecular organometallic complexes of Ln(II) ions (Ln = lanthanide) has been examined for the first time. XPS spectra were obtained on the air-sensitive molecular trivalent 4fn Cp'3LnIII complexes (Ln = Sm, Eu, Gd, Tb; Cp' = C5H4SiMe3) and compared to those of the highly reactive divalent complexes, [K(crypt)][Cp'3LnII] (crypt = 2.2.2-cryptand), which have either 4fn+1 (Sm, Eu) or 4fn5d1 electron configurations (Gd, Tb). The Ln 4d, Si 2p, and C 1s regions of the Ln(III) and Ln(II) complexes were identified and compared. The metal 4d peaks of these molecular lanthanide complexes were used diagnostically to compare oxidation states. The valence region of the Gd(III) and Gd(II) complexes was also examined with XPS and density function theory/random phase approximation (DFT/RPA) calculations, and this led to the tentative assignment of a signal from the 5d1 electron consistent with a 4f75d1 electron configuration for Gd(II).

13.
Histochem Cell Biol ; 155(2): 291-300, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33598824

RESUMO

It has long been appreciated that the endoplasmic reticulum (ER) and mitochondria, organelles important for regular cell function and survival, also play key roles in pathogenesis of various lung diseases, including asthma, fibrosis, and infections. Alterations in processes regulated within these organelles, including but not limited to protein folding in the ER and oxidative phosphorylation in the mitochondria, are important in disease pathogenesis. In recent years it has also become increasingly apparent that organelle structure dictates function. It is now clear that organelles must maintain precise organization and localization for proper function. Newer microscopy capabilities have allowed the scientific community to reveal, via 3D imaging, that the structure of these organelles and their interactions with each other are a main component of regulating function and, therefore, effects on the disease state. In this review, we will examine how 3D imaging through techniques could allow advancements in knowledge of how the ER and mitochondria function and the roles they may play in lung epithelia in progression of lung disease.


Assuntos
Retículo Endoplasmático/ultraestrutura , Células Epiteliais/ultraestrutura , Imageamento Tridimensional , Pneumopatias/metabolismo , Pulmão/ultraestrutura , Mitocôndrias/ultraestrutura , Animais , Retículo Endoplasmático/química , Retículo Endoplasmático/metabolismo , Células Epiteliais/química , Células Epiteliais/metabolismo , Humanos , Pulmão/metabolismo , Pneumopatias/patologia , Microscopia Confocal , Microscopia Eletrônica , Mitocôndrias/química , Mitocôndrias/metabolismo
14.
Int J Mol Sci ; 22(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34681784

RESUMO

Mitochondria regulate a myriad of cellular functions. Dysregulation of mitochondrial control within airway epithelial cells has been implicated in the pro-inflammatory response to allergens in asthma patients. Because of their multifaceted nature, mitochondrial structure must be tightly regulated through fission and fusion. Dynamin Related Protein 1 (DRP1) is a key driver of mitochondrial fission. During allergic asthma, airway epithelial mitochondria appear smaller and structurally altered. The role of DRP1-mediated mitochondrial fission, however, has not been fully elucidated in epithelial response to allergens. We used a Human Bronchial Epithelial Cell line (HBECs), primary Mouse Tracheal Epithelial Cells (MTECs), and conditional DRP1 ablation in lung epithelial cells to investigate the impact of mitochondrial fission on the pro-inflammatory response to house dust mite (HDM) in vitro and in vivo. Our data suggest that, following HDM challenge, mitochondrial fission is rapidly upregulated in airway epithelial cells and precedes production of pro-inflammatory cytokines and chemokines. Further, deletion of Drp1 in lung epithelial cells leads to decreased fission and enhanced pro-inflammatory signaling in response to HDM in vitro, as well as enhanced airway hyper-responsiveness (AHR), inflammation, differential mucin transcription, and epithelial cell death in vivo. Mitochondrial fission, therefore, regulates the lung epithelial pro-inflammatory response to HDM.


Assuntos
Alérgenos/farmacologia , Dinaminas/fisiologia , Dinâmica Mitocondrial/genética , Hipersensibilidade Respiratória/genética , Mucosa Respiratória/efeitos dos fármacos , Animais , Brônquios/efeitos dos fármacos , Brônquios/fisiologia , Células Cultivadas , Dinaminas/genética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Transgênicos , Hipersensibilidade Respiratória/induzido quimicamente , Hipersensibilidade Respiratória/imunologia , Hipersensibilidade Respiratória/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo
15.
BMC Med ; 18(1): 288, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-33109212

RESUMO

BACKGROUND: Advances in antiretroviral therapies have greatly improved the survival of people living with human immunodeficiency virus (HIV) infection (PLWH); yet, PLWH have a higher risk of cardiovascular disease than those without HIV. While numerous genetic loci have been linked to cardiometabolic risk in the general population, genetic predictors of the excessive risk in PLWH are largely unknown. METHODS: We screened for common and HIV-specific genetic variants associated with variation in lipid levels in 6284 PLWH (3095 European Americans [EA] and 3189 African Americans [AA]), from the Centers for AIDS Research Network of Integrated Clinical Systems cohort. Genetic hits found exclusively in the PLWH cohort were tested for association with other traits. We then assessed the predictive value of a series of polygenic risk scores (PRS) recapitulating the genetic burden for lipid levels, type 2 diabetes (T2D), and myocardial infarction (MI) in EA and AA PLWH. RESULTS: We confirmed the impact of previously reported lipid-related susceptibility loci in PLWH. Furthermore, we identified PLWH-specific variants in genes involved in immune cell regulation and previously linked to HIV control, body composition, smoking, and alcohol consumption. Moreover, PLWH at the top of European-based PRS for T2D distribution demonstrated a > 2-fold increased risk of T2D compared to the remaining 95% in EA PLWH but to a much lesser degree in AA. Importantly, while PRS for MI was not predictive of MI risk in AA PLWH, multiethnic PRS significantly improved risk stratification for T2D and MI. CONCLUSIONS: Our findings suggest that genetic loci involved in the regulation of the immune system and predisposition to risky behaviors contribute to dyslipidemia in the presence of HIV infection. Moreover, we demonstrate the utility of the European-based and multiethnic PRS for stratification of PLWH at a high risk of cardiometabolic diseases who may benefit from preventive therapies.


Assuntos
Fatores de Risco Cardiometabólico , Estudo de Associação Genômica Ampla/métodos , Infecções por HIV/complicações , Estudos de Coortes , Feminino , Infecções por HIV/genética , Humanos , Masculino , Pessoa de Meia-Idade
16.
Inorg Chem ; 59(23): 17077-17083, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33226794

RESUMO

The electrochemical properties of U(III)-in-crypt (crypt = 2.2.2-cryptand) were examined in dimethylformamide (DMF) and acetonitrile (MeCN) to determine the oxidative stability offered by crypt as a ligand. Cyclic voltammetry revealed a U(III)/U(IV) irreversible oxidation at EPA= -0.49 V (vs Fe(C5H5)2+/0) in DMF and at EPA= -0.31 V (vs Fe(C5H5)2+/0) in MeCN. The electrochemistry of U(III)-in-crypt complexes in the presence of water was also examined. These studies are supported by crystallographically characterized examples of U(III)-in-crypt complexes as DMF, MeCN, and water adducts.

17.
Nature ; 510(7505): 381-4, 2014 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-24943953

RESUMO

Water has a number of anomalous physical properties, and some of these become drastically enhanced on supercooling below the freezing point. Particular interest has focused on thermodynamic response functions that can be described using a normal component and an anomalous component that seems to diverge at about 228 kelvin (refs 1-3). This has prompted debate about conflicting theories that aim to explain many of the anomalous thermodynamic properties of water. One popular theory attributes the divergence to a phase transition between two forms of liquid water occurring in the 'no man's land' that lies below the homogeneous ice nucleation temperature (TH) at approximately 232 kelvin and above about 160 kelvin, and where rapid ice crystallization has prevented any measurements of the bulk liquid phase. In fact, the reliable determination of the structure of liquid water typically requires temperatures above about 250 kelvin. Water crystallization has been inhibited by using nanoconfinement, nanodroplets and association with biomolecules to give liquid samples at temperatures below TH, but such measurements rely on nanoscopic volumes of water where the interaction with the confining surfaces makes the relevance to bulk water unclear. Here we demonstrate that femtosecond X-ray laser pulses can be used to probe the structure of liquid water in micrometre-sized droplets that have been evaporatively cooled below TH. We find experimental evidence for the existence of metastable bulk liquid water down to temperatures of 227(-1)(+2) kelvin in the previously largely unexplored no man's land. We observe a continuous and accelerating increase in structural ordering on supercooling to approximately 229 kelvin, where the number of droplets containing ice crystals increases rapidly. But a few droplets remain liquid for about a millisecond even at this temperature. The hope now is that these observations and our detailed structural data will help identify those theories that best describe and explain the behaviour of water.

18.
J Helminthol ; 94: e189, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32907643

RESUMO

Fascioliasis is a zoonotic disease caused by liver flukes transmitted by freshwater lymnaeid snails. Donkey and horse reservoir roles have been highlighted in human endemic areas. Liver fluke infection in mules has received very limited research. Their role in disease transmission, epidemiological importance and Fasciola hepatica pathogenicity are studied for the first time. Prevalence was 39.5% in 81 mules from Aconcagua, and 24.4% in 127 from Uspallata, in high-altitude areas of Mendoza province, Argentina. A mean amount of 101,242 eggs/mule/day is estimated. Lymnaeids from Uspallata proved to belong to ribosomal DNA internal transcribed spacer (ITS) markers ITS-1 and ITS-2 combined haplotype 3C of Galba truncatula. These lymnaeids were experimentally susceptible to infection by egg miracidia from mules. Infectivity, number of cercariae/snail and shedding period fit the enhanced F. hepatica/G. truncatula transmission pattern at very high altitude. This indicates that the mule is able to maintain the F. hepatica cycle independently. Individual burdens of 20 and 97 flukes were found. Mule infection susceptibility is intermediate between donkey and horse, although closer to the latter. Anatomo-pathology and histopathology indicate that massive infection may cause mule death. Haematological value decreases of red blood cells, haemoglobin, leucocytes and lymphocytes indicate anaemia and strong immunosuppression. Strongly increased biochemical marker values indicate liver function alterations. The mule probably played a role in the past exchanges with Chile and Bolivia through Mendoza province. Evidence suggests that mules could contribute to the spread of both F. hepatica and G. truncatula to human fascioliasis-endemic areas in these countries.


Assuntos
Reservatórios de Doenças/veterinária , Equidae/parasitologia , Fasciola hepatica/patogenicidade , Fasciolíase/transmissão , Fasciolíase/veterinária , Zoonoses/transmissão , Animais , Argentina/epidemiologia , Reservatórios de Doenças/parasitologia , Fasciola hepatica/genética , Fasciola hepatica/isolamento & purificação , Fasciolíase/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Masculino , Contagem de Ovos de Parasitas , Prevalência , Virulência , Zoonoses/epidemiologia , Zoonoses/parasitologia
19.
Angew Chem Int Ed Engl ; 59(37): 16141-16146, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32441487

RESUMO

Lanthanide triflates have been used to incorporate NdIII and SmIII ions into the 2.2.2-cryptand ligand (crypt) to explore their reductive chemistry. The Ln(OTf)3 complexes (Ln=Nd, Sm; OTf=SO3 CF3 ) react with crypt in THF to form the THF-soluble complexes [LnIII (crypt)(OTf)2 ][OTf] with two triflates bound to the metal encapsulated in the crypt. Reduction of these LnIII -in-crypt complexes using KC8 in THF forms the neutral LnII -in-crypt triflate complexes [LnII (crypt)(OTf)2 ]. DFT calculations on [NdII (crypt)]2+ ], the first NdII cryptand complex, assign a 4f4 electron configuration to this ion.

20.
RNA ; 23(6): 952-967, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28325844

RESUMO

Proteins of the Sm and Sm-like (LSm) families, referred to collectively as (L)Sm proteins, are found in all three domains of life and are known to promote a variety of RNA processes such as base-pair formation, unwinding, RNA degradation, and RNA stabilization. In eukaryotes, (L)Sm proteins have been studied, inter alia, for their role in pre-mRNA splicing. In many organisms, the LSm proteins form two distinct complexes, one consisting of LSm1-7 that is involved in mRNA degradation in the cytoplasm, and the other consisting of LSm2-8 that binds spliceosomal U6 snRNA in the nucleus. We recently characterized the splicing proteins from the red alga Cyanidioschyzon merolae and found that it has only seven LSm proteins. The identities of CmLSm2-CmLSm7 were unambiguous, but the seventh protein was similar to LSm1 and LSm8. Here, we use in vitro binding measurements, microscopy, and affinity purification-mass spectrometry to demonstrate a canonical splicing function for the C. merolae LSm complex and experimentally validate our bioinformatic predictions of a reduced spliceosome in this organism. Copurification of Pat1 and its associated mRNA degradation proteins with the LSm proteins, along with evidence of a cytoplasmic fraction of CmLSm complexes, argues that this complex is involved in both splicing and cytoplasmic mRNA degradation. Intriguingly, the Pat1 complex also copurifies with all four snRNAs, suggesting the possibility of a spliceosome-associated pre-mRNA degradation complex in the nucleus.


Assuntos
Precursores de RNA/genética , Splicing de RNA , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Rodófitas/genética , Rodófitas/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Biologia Computacional/métodos , Imunoprecipitação , Modelos Moleculares , Conformação de Ácido Nucleico , Filogenia , Ligação Proteica , Conformação Proteica , Transporte Proteico , Precursores de RNA/química , Estabilidade de RNA , RNA Mensageiro/química , RNA Nuclear Pequeno/química , RNA Nuclear Pequeno/genética , Proteínas de Ligação a RNA/química , Espectrometria de Massas em Tandem
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