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1.
Med Educ ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31958172

RESUMO

For physicians, medical school is the point of entry to the healthcare system, a work environment with burnout rates so high they constitute a public health crisis. Talented, accomplished students enter medical school, then face an increased burden of anxiety, depression, and suicidal ideation relative to age-matched peers, once their studies commence.1,2 A growing body of literature documents the psychological distress experienced by rising numbers of medical students, the unique stressors of medical education, and various interventions to improve the learning environment.

2.
Thorax ; 2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31822523

RESUMO

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a rapidly progressive, fatal lung disease that affects older adults. One of the detrimental natural histories of IPF is acute exacerbation of IPF (AE-IPF), of which bacterial infection is reported to play an important role. However, the mechanism by which bacterial infection modulates the fibrotic response remains unclear. OBJECTIVES: Altered glucose metabolism has been implicated in the pathogenesis of fibrotic lung diseases. We have previously demonstrated that glucose transporter 1 (GLUT1)-dependent glycolysis regulates fibrogenesis in a murine fibrosis model. To expand on these findings, we hypothesised that GLUT1-dependent glycolysis regulates acute exacerbation of lung fibrogenesis during bacterial infection via AIM2 inflammasome activation. RESULTS: In our current study, using a murine model of Streptococcus pneumoniae (S. pneumoniae) infection, we investigated the potential role of GLUT1 on mediating fibrotic responses to an acute exacerbation during bleomycin-induced fibrosis. The results of our current study illustrate that GLUT1 deficiency ameliorates S. pneumoniae-mediated exacerbation of lung fibrosis (wild type (WT)/phosphate buffered saline (PBS), n=3; WT/S. pneumoniae, n=3; WT/Bleomycin, n=5 ; WT/Bleomycin+S. pneumoniae, n=7; LysM-Cre-Glut1fl/f /PBS, n=3; LysM-Cre-Glut1fl/fl /S. pneumoniae, n=3; LysM-Cre-Glut1fl/fl /Bleomycin, n=6; LysM-Cre-Glut1fl/fl /Bleomycin+S. pneumoniae, n=9, p=0.041). Further, the AIM2 inflammasome, a multiprotein complex essential for sensing cytosolic bacterial DNA as a danger signal, is an important regulator of this GLUT1-mediated fibrosis and genetic deficiency of AIM2 reduced bleomycin-induced fibrosis after S. pneumoniae infection (WT/PBS, n=6; WT/Bleomycin+S. pneumoniae, n=15; Aim2-/-/PBS, n=6, Aim2-/-/Bleomycin+S. pneumoniae, n=11, p=0.034). GLUT1 deficiency reduced expression and function of the AIM2 inflammasome, and AIM2-deficient mice showed substantial reduction of lung fibrosis after S. pneumoniae infection. CONCLUSION: Our results demonstrate that GLUT1-dependent glycolysis promotes exacerbation of lung fibrogenesis during S. pneumoniae infection via AIM2 inflammasome activation.

5.
Sci Rep ; 9(1): 14802, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31615996

RESUMO

Compelling preclinical studies indicate that low-dose carbon monoxide (CO) abrogates experimental lung fibrosis. We recently reported the results of a multicenter, double-blinded, clinical trial of inhaled CO in patients with idiopathic pulmonary fibrosis (IPF). Identifying no significantly changes in metalloproteinase-7 (MMP7) serum concentration, or secondary endpoints of physiologic measurements, hospitalization, death, or patient-reported outcomes. In the present study, we evaluated the effect of low dose CO exposure (100-200 ppm) for 12 weeks on genome-wide gene expression in peripheral blood mononuclear cells (PBMC) derived from these IPF study subjects. We conducted transcriptome profiling on 38 IPF subjects with time points available at 0, 12, and 24 weeks. Total RNA isolated from PBMCs was hybridized onto the Affymetrix Human Gene 2.0 ST Array. We identified 621 genes significantly upregulated in the 24-week CO exposed group compared with the 12-week. Pathway analysis demonstrated association with Oxidative Phosphorylation (adjusted P < 0.05). We identified a clear CO signature dominated with 23 oxidative phosphorylation-related genes (FDR <10%). We confirmed the expression of nine selected gene products using Nanostring's nCounter analysis system. These findings suggest this signature may serve as a potential genomic biomarker for CO exposure and for potential titration of dosage to allow precision testing of therapies in future low dose CO therapeutic studies in IPF.

6.
Sci Rep ; 9(1): 12942, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31506522

RESUMO

Mitochondrial DNA (mtDNA) heteroplasmies are associated with various diseases but the transmission of heteroplasmy from mtDNA to mitochondrial RNA (mtRNA) remains unclear. We compared heteroplasmies in mtRNA from 446 human B-lymphoblastoid cell lines to their corresponding mtDNA using deep sequencing data from two independent studies. We observed 2786 heteroplasmies presenting in both DNA and RNA at 1% frequency cutoff. Among them, the frequencies of 2427 (87.1%) heteroplasmies were highly consistent (less than 5% frequency difference) between DNA and RNA. To validate these frequency consistencies, we isolated DNA and RNA simultaneously from GM12282 cell line used in those two sequencing studies, and resequenced its heteroplasmy sites. Interestingly, we also observed the rapid changes of heteroplasmy frequencies during 4 weeks of the cell culture: the frequencies at Day 14 increased by >25% than those at Day 0. However, the heteroplasmy frequencies from the same time point were highly consistent. In summary, our analysis on public data together with in vitro study indicates that the heteroplasmies in DNA can be transcribed into RNA with high fidelity. Meanwhile, the observed rapid-changing heteroplasmy frequency can potentially disturb cell functions, which could be an overlooked confounding factor in cell line related studies.

7.
Chest ; 156(6): 1120-1136, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31381882

RESUMO

BACKGROUND: Despite numerous publications on mitochondrial DNA (mtDNA) in the last decade it remains to be seen whether mtDNA can be used clinically. We conducted a systematic review to assess circulating cell-free mtDNA as a biomarker of mortality in critically ill patients. METHODS: This systematic review was registered with PROSPERO (CRD42016046670). PubMed, CINAHL, the Cochrane Library, Embase, Scopus, and Web of Science, and reference lists of retrieved articles were searched. Studies measuring circulating cell-free mtDNA and reporting on all-cause mortality in critically ill adult and pediatric patients were included. The primary and secondary outcomes were mortality and morbidity, respectively. RESULTS: Of the 1,566 initially retrieved publications, 40 studies were included, accounting for 3,450 critically ill patients. Substantial differences between studies were noted in how mtDNA was isolated and measured. Sixteen of the 40 included studies (40%) explored the association between mtDNA levels and mortality; of those 16 studies, 11 (68.8%) reported a statistically significant association. The area under the receiver operating characteristic (AUROC) curve for mtDNA and mortality was calculated for 10 studies and ranged from 0.61 to 0.95. CONCLUSIONS: There is growing interest in mtDNA as a predictor of mortality in critically ill patients. Most studies are small, lack validation cohorts, and utilize different protocols to measure mtDNA. When reported, AUROC analysis usually suggests a statistically significant association between mtDNA and mortality. Standardization of mtDNA protocols and the completion of a large, prospective, multicenter trial may be warranted to firmly establish the clinical usefulness of mtDNA.

8.
JCI Insight ; 4(15)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31391333

RESUMO

Necroptosis is a genetically regulated form of necrotic cell death that has emerged as an important pathway in human disease. The necroptosis pathway is induced by a variety of signals, including death receptor ligands, and regulated by receptor-interacting protein kinases 1 and 3 (RIPK1 and RIPK3) and mixed-lineage kinase domain-like pseudokinase (MLKL), which form a regulatory necrosome complex. RIPK3-mediated phosphorylation of MLKL executes necroptosis. Recent studies, using animal models of tissue injury, have revealed that RIPK3 and MLKL are key effectors of injury propagation. This Review explores the functional roles of RIPK3 and MLKL as crucial pathogenic determinants and markers of disease progression and severity in experimental models of human disease, including acute and chronic pulmonary diseases; renal, hepatic, cardiovascular, and neurodegenerative diseases; cancer; and critical illness.

9.
Cells ; 8(8)2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434287

RESUMO

Idiopathic pulmonary fibrosis (IPF) has been linked to chronic lung inflammation. Drosha ribonuclease III (DROSHA), a class 2 ribonuclease III enzyme, plays a key role in microRNA (miRNA) biogenesis. However, the mechanisms by which DROSHA affects the lung inflammation during idiopathic pulmonary fibrosis (IPF) remain unclear. Here, we demonstrate that DROSHA regulates the absent in melanoma 2 (AIM2) inflammasome activation during idiopathic pulmonary fibrosis (IPF). Both DROSHA and AIM2 protein expression were elevated in alveolar macrophages of patients with IPF. We also found that DROSHA and AIM2 protein expression were increased in alveolar macrophages of lung tissues in a mouse model of bleomycin-induced pulmonary fibrosis. DROSHA deficiency suppressed AIM2 inflammasome-dependent caspase-1 activation and interleukin (IL)-1ß and IL-18 secretion in primary mouse alveolar macrophages and bone marrow-derived macrophages (BMDMs). Transduction of microRNA (miRNA) increased the formation of the adaptor apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) specks, which is required for AIM2 inflammasome activation in BMDMs. Our results suggest that DROSHA promotes AIM2 inflammasome activation-dependent lung inflammation during IPF.

10.
Nat Commun ; 10(1): 3390, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358769

RESUMO

Accumulating evidence illustrates a fundamental role for mitochondria in lung alveolar type 2 epithelial cell (AEC2) dysfunction in the pathogenesis of idiopathic pulmonary fibrosis. However, the role of mitochondrial fusion in AEC2 function and lung fibrosis development remains unknown. Here we report that the absence of the mitochondrial fusion proteins mitofusin1 (MFN1) and mitofusin2 (MFN2) in murine AEC2 cells leads to morbidity and mortality associated with spontaneous lung fibrosis. We uncover a crucial role for MFN1 and MFN2 in the production of surfactant lipids with MFN1 and MFN2 regulating the synthesis of phospholipids and cholesterol in AEC2 cells. Loss of MFN1, MFN2 or inhibiting lipid synthesis via fatty acid synthase deficiency in AEC2 cells exacerbates bleomycin-induced lung fibrosis. We propose a tenet that mitochondrial fusion and lipid metabolism are tightly linked to regulate AEC2 cell injury and subsequent fibrotic remodeling in the lung.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31194918

RESUMO

No previously suggested biomarkers of nasal mucosal inflammation have been practically applied in clinical fields, and nasal epithelium-derived secreted proteins as biomarkers have not specifically been investigated. The goal of this study was to identify secreted proteins that dynamically change during the differentiation from basal cells to fully differentiated cells and examine whether nasal epithelium-derived proteins can be used as biomarkers of nasal mucosal inflammation, such as chronic rhinosinusitis. To achieve this goal, we analyzed two secretomes using the isobaric tag for relative and absolute quantification (iTRAQ) technique. From in vitro secretomes, we identified the proteins altered in apical secretions of primary human nasal epithelial cells (HNECs) according to the degree of differentiation; from in vivo secretomes, we identified the increased proteins in nasal lavage (NAL) fluids obtained from patients 2 weeks after endoscopic sinus surgery for chronic sinusitis. We then used a parallel approach to identify specific biomarkers of nasal mucosal inflammation; first, we selected apolipoprotein E (APOE) as a nasal epithelial cell-derived biomarker through screening proteins that were upregulated in both in vitro and in vivo secretomes, and verified highly secreted APOE in NAL fluids of the patients by Western blotting. Next, we selected periostin (POSTN) as an inflammatory mediator-inducible biomarker from in vivo secretomes, whose secretion was not induced under in vitro culture condition. We demonstrated that those two nasal epithelium-derived proteins are possible biomarkers of nasal mucosal inflammation.

12.
13.
Acad Med ; 94(5): 630-633, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31026234

RESUMO

Mentorship is central to academic medicine and its missions, and it has long played a critical role in the training and career development of physicians and scientists. A growing body of literature has documented the positive impact of mentorship on various outcomes, including research productivity, academic promotion, faculty retention, and career satisfaction. These benefits span academic medical centers' missions and have the potential to enhance biomedical research, patient care, education, and faculty diversity and leadership.In this Invited Commentary, the authors argue that a dynamic culture of mentorship is essential to the success of academic medical centers and should be elevated to the level of a major strategic priority. This culture of mentorship would capitalize on an institution's intellectual resources and seek to develop leaders in biomedical discovery, patient care, and education. The bidirectional transmission of knowledge between mentors and mentees, through both formal programs and informal relationships, can foster the growth of faculty members needed to meet the complex challenges currently confronting medical schools and teaching hospitals.Developing a culture of mentorship requires a strong commitment by leaders at all levels to nurture the next generation of physicians and scientists as well as grassroots efforts by trainees and faculty to seek out and create mentorship opportunities. The authors conclude by outlining possible mechanisms and incentives for elevating mentorship to the level of a strategic priority to strengthen academic medical centers across their missions.

14.
Science ; 364(6436)2019 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-30975860

RESUMO

To understand the health impact of long-duration spaceflight, one identical twin astronaut was monitored before, during, and after a 1-year mission onboard the International Space Station; his twin served as a genetically matched ground control. Longitudinal assessments identified spaceflight-specific changes, including decreased body mass, telomere elongation, genome instability, carotid artery distension and increased intima-media thickness, altered ocular structure, transcriptional and metabolic changes, DNA methylation changes in immune and oxidative stress-related pathways, gastrointestinal microbiota alterations, and some cognitive decline postflight. Although average telomere length, global gene expression, and microbiome changes returned to near preflight levels within 6 months after return to Earth, increased numbers of short telomeres were observed and expression of some genes was still disrupted. These multiomic, molecular, physiological, and behavioral datasets provide a valuable roadmap of the putative health risks for future human spaceflight.


Assuntos
Adaptação Fisiológica , Astronautas , Voo Espacial , Imunidade Adaptativa , Peso Corporal , Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Dano ao DNA , Metilação de DNA , Microbioma Gastrointestinal , Instabilidade Genômica , Humanos , Masculino , Homeostase do Telômero , Fatores de Tempo , Estados Unidos , United States National Aeronautics and Space Administration
15.
Cell Rep ; 26(7): 1880-1892.e6, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30759397

RESUMO

Circadian rhythms are a hallmark of physiology, but how such daily rhythms organize cellular catabolism is poorly understood. Here, we used proteomics to map daily oscillations in autophagic flux in mouse liver and related these rhythms to proteasome activity. We also explored how systemic inflammation affects the temporal structure of autophagy. Our data identified a globally harmonized rhythm for basal macroautophagy, chaperone-mediated autophagy, and proteasomal activity, which concentrates liver proteolysis during the daytime. Basal autophagy rhythms could be resolved into two antiphase clusters that were distinguished by the subcellular location of targeted proteins. Inflammation induced by lipopolysaccharide reprogrammed autophagic flux away from a temporal pattern that favors cytosolic targets and toward the turnover of mitochondrial targets. Our data detail how daily biological rhythms connect the temporal, spatial, and metabolic aspects of protein catabolism.

16.
Am J Respir Cell Mol Biol ; 60(4): 420-433, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30359079

RESUMO

A positive link between persistent cellular motion and a defective tight junction barrier allows increased antigenic penetration and contact between ligand-receptor pairs, leading to exacerbated allergic airway inflammation and remodeling. Given that collective cell migration involves cell-cell and cell-extracellular matrix adhesions, and given that IL-4 induces epithelial barrier dysfunction and decreases cell-extracellular matrix adhesions, we hypothesized that IL-4 may induce collective migration in the well-differentiated primary human nasal epithelial cells (HNECs). Well-differentiated HNECs were treated with IL-4, and the effects of IL-4 on cell migration were investigated using genetic and pharmacological approaches, live-cell imaging, a vertex model, and immunostaining. IL-4 disrupted the expression and localization of the tight junction proteins zonula occludens 1 and occludin, and it induced the cleavage and asymmetric distribution of E-cadherin in the HNEC layers. It also induced collective epithelial migration and cell shape changes driven by actin cytoskeleton reorganization. In addition, the effect of IL-4 on collective HNEC migration was reversed by pharmacologic and genetic inhibition of the αv-integrin-activating enzyme furin, and function-blocking antibodies for αvß5 or αvß6. In IL-4-stimulated cells, both anti-αvß5 and anti-αvß6 inhibited the phosphorylation of focal adhesion kinase. Furthermore, both ß5- and ß6-integrins were enriched in basal cells in the injured airway epithelium with allergic rhinitis. These findings suggest that αvß5 and αvß6 serve as critical mechanoreceptors in IL-4-induced collective HNEC migration through the focal adhesion kinase signaling pathway. These results have implications for targeting treatment of exacerbation of respiratory allergic diseases.

17.
Chest ; 155(3): 474-482, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30359616

RESUMO

BACKGROUND: Observational studies suggest that some patients meeting criteria for ARDS no longer fulfill the oxygenation criterion early in the course of their illness. This subphenotype of rapidly improving ARDS has not been well characterized. We attempted to assess the prevalence, characteristics, and outcomes of rapidly improving ARDS and to identify which variables are useful to predict it. METHODS: A secondary analysis was performed of patient level data from six ARDS Network randomized controlled trials. We defined rapidly improving ARDS, contrasted with ARDS > 1 day, as extubation or a Pao2 to Fio2 ratio (Pao2:Fio2) > 300 on the first study day following enrollment. RESULTS: The prevalence of rapidly improving ARDS was 10.5% (458 of 4,361 patients) and increased over time. Of the 1,909 patients enrolled in the three most recently published trials, 197 (10.3%) were extubated on the first study day, and 265 (13.9%) in total had rapidly improving ARDS. Patients with rapidly improving ARDS had lower baseline severity of illness and lower 60-day mortality (10.2% vs 26.3%; P < .0001) than ARDS > 1 day. Pao2:Fio2 at screening, change in Pao2:Fio2 from screening to enrollment, use of vasopressor agents, Fio2 at enrollment, and serum bilirubin levels were useful predictive variables. CONCLUSIONS: Rapidly improving ARDS, mostly defined by early extubation, is an increasingly prevalent and distinct subphenotype, associated with better outcomes than ARDS > 1 day. Enrollment of patients with rapidly improving ARDS may negatively affect the prognostic enrichment and contribute to the failure of therapeutic trials.

18.
Crit Care ; 22(1): 360, 2018 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-30594224

RESUMO

BACKGROUND: Cell-free plasma mitochondrial DNA (mtDNA) levels are associated with endothelial dysfunction and differential outcomes in critical illness. A substantial alteration in metabolic homeostasis is commonly observed in severe critical illness. We hypothesized that metabolic profiles significantly differ between critically ill patients relative to their level of plasma mtDNA. METHODS: We performed a metabolomic study with biorepository plasma samples collected from 73 adults with systemic inflammatory response syndrome or sepsis at a single academic medical center. Patients were treated in a 20-bed medical ICU between 2008 and 2010. To identify key metabolites and metabolic pathways related to plasma NADH dehydrogenase 1 (ND1) mtDNA levels in critical illness, we first generated metabolomic data using gas and liquid chromatography-mass spectroscopy. We performed fold change analysis and volcano plot visualization based on false discovery rate-adjusted p values to evaluate the distribution of individual metabolite concentrations relative to ND1 mtDNA levels. We followed this by performing orthogonal partial least squares discriminant analysis to identify individual metabolites that discriminated ND1 mtDNA groups. We then interrogated the entire metabolomic profile using pathway overrepresentation analysis to identify groups of metabolite pathways that were different relative to ND1 mtDNA levels. RESULTS: Metabolomic profiles significantly differed in critically ill patients with ND1 mtDNA levels ≥ 3200 copies/µl plasma relative to those with an ND1 mtDNA level < 3200 copies/µl plasma. Several analytical strategies showed that patients with ND1 mtDNA levels ≥ 3200 copies/µl plasma had significant decreases in glycerophosphocholines and increases in short-chain acylcarnitines. CONCLUSIONS: Differential metabolic profiles during critical illness are associated with cell-free plasma ND1 mtDNA levels that are indicative of cell damage. Elevated plasma ND1 mtDNA levels are associated with decreases in glycerophosphocholines and increases in short-chain acylcarnitines that reflect phospholipid metabolism dysregulation and decreased mitochondrial function, respectively.


Assuntos
DNA Mitocondrial/farmacologia , Metabolômica/métodos , Adulto , Idoso , Boston , Estado Terminal/terapia , DNA Mitocondrial/efeitos adversos , DNA Mitocondrial/uso terapêutico , Análise Discriminante , Células Endoteliais/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sistema de Registros/estatística & dados numéricos
19.
J Crit Care ; 47: 49-54, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29898428

RESUMO

PURPOSE: We examined whether patients with acute respiratory distress syndrome (ARDS) lacking risk factors are enrolled in therapeutic trials and assessed their clinical characteristics and outcomes. METHODS: We performed a secondary analysis of patient-level data pooled from the ARMA, ALVEOLI, FACTT, ALTA and EDEN ARDSNet randomized controlled trials obtained from the Biologic Specimen and Data Repository Information Coordinating Center of the National Heart, Lung and Blood Institute. We compared baseline characteristics and clinical outcomes (before and after adjustment using Poisson regression model) of ARDS patients with versus without risk factors. RESULTS: Of 3733 patients with ARDS, 81 (2.2%) did not have an identifiable risk factor. Patients without risk factors were younger, had lower baseline severity of illness, were more likely to have the ARDS resolve rapidly (i.e., within 24 h) (p < 0.001) and they had more ventilator-free days (median 21; p = 0.003), more intensive care unit-free days (18; p = 0.010), and more non-pulmonary organ failure-free days (24; p < 0.001) than comparators (17, 14 and 18, respectively). Differences persisted after adjustment for potential confounders. CONCLUSIONS: Patients with ARDS without identifiable risk factors are enrolled in therapeutic trials and may have better outcomes, including a higher proportion of rapidly resolving ARDS, than those with risk factors.


Assuntos
Tempo de Internação , Seleção de Pacientes , Síndrome do Desconforto Respiratório do Adulto/epidemiologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Respiração Artificial , Síndrome do Desconforto Respiratório do Adulto/etiologia , Síndrome do Desconforto Respiratório do Adulto/mortalidade , Fatores de Risco , Estados Unidos/epidemiologia
20.
JCI Insight ; 3(11)2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29875323

RESUMO

Sepsis causes acute kidney injury (AKI) in critically ill patients, although the pathophysiology remains unclear. The receptor-interacting protein kinase-3 (RIPK3), a cardinal regulator of necroptosis, has recently been implicated in the pathogenesis of human disease. In mice subjected to polymicrobial sepsis, we demonstrate that RIPK3 promotes sepsis-induced AKI. Utilizing genetic deletion and biochemical approaches in vitro and in vivo, we identify a potentially novel pathway by which RIPK3 aggravates kidney tubular injury independently of the classical mixed lineage kinase domain-like protein-dependent (MLKL-dependent) necroptosis pathway. In kidney tubular epithelial cells, we show that RIPK3 promotes oxidative stress and mitochondrial dysfunction involving upregulation of NADPH oxidase-4 (NOX4) and inhibition of mitochondrial complex I and -III, and that RIPK3 and NOX4 are critical for kidney tubular injury in vivo. Furthermore, we demonstrate that RIPK3 is required for increased mitochondrial translocation of NOX4 in response to proinflammatory stimuli, by a mechanism involving protein-protein interactions. Finally, we observed elevated urinary and plasma RIPK3 levels in human patients with sepsis-induced AKI, representing potential markers of this condition. In conclusion, we identify a pathway by which RIPK3 promotes kidney tubular injury via mitochondrial dysfunction, independently of MLKL, which may represent a promising therapeutic target in sepsis-induced AKI.


Assuntos
Lesão Renal Aguda/patologia , Túbulos Renais/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Choque Séptico/complicações , Lesão Renal Aguda/sangue , Lesão Renal Aguda/etiologia , Lesão Renal Aguda/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose , Biomarcadores/sangue , Biomarcadores/urina , Linhagem Celular , Células Epiteliais/citologia , Células Epiteliais/patologia , Células Epiteliais/ultraestrutura , Feminino , Humanos , Túbulos Renais/citologia , Túbulos Renais/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mitocôndrias/patologia , Mitocôndrias/ultraestrutura , NADPH Oxidase 4/metabolismo , Necrose/patologia , Estresse Oxidativo , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/sangue , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/urina , Choque Séptico/sangue , Choque Séptico/urina , Regulação para Cima , Adulto Jovem
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