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1.
Nat Immunol ; 17(11): 1252-1262, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27595231

RESUMO

The mammalian cytoplasmic multi-tRNA synthetase complex (MSC) is a depot system that regulates non-translational cellular functions. Here we found that the MSC component glutamyl-prolyl-tRNA synthetase (EPRS) switched its function following viral infection and exhibited potent antiviral activity. Infection-specific phosphorylation of EPRS at Ser990 induced its dissociation from the MSC, after which it was guided to the antiviral signaling pathway, where it interacted with PCBP2, a negative regulator of mitochondrial antiviral signaling protein (MAVS) that is critical for antiviral immunity. This interaction blocked PCBP2-mediated ubiquitination of MAVS and ultimately suppressed viral replication. EPRS-haploid (Eprs+/-) mice showed enhanced viremia and inflammation and delayed viral clearance. This stimulus-inducible activation of MAVS by EPRS suggests an unexpected role for the MSC as a regulator of immune responses to viral infection.


Assuntos
Aminoacil-tRNA Sintetases/metabolismo , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Viroses/imunologia , Viroses/metabolismo , Aminoacil-tRNA Sintetases/química , Aminoacil-tRNA Sintetases/genética , Animais , Antivirais/farmacologia , Modelos Animais de Doenças , Imunidade Inata , Camundongos , Camundongos Knockout , Peptídeos/farmacologia , Fosforilação , Ligação Proteica , Infecções por Vírus de RNA/imunologia , Infecções por Vírus de RNA/metabolismo , Infecções por Vírus de RNA/virologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/imunologia , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais , Ubiquitinação , Viroses/virologia , Replicação Viral
2.
EMBO J ; 42(19): e113481, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37575012

RESUMO

The NLRP3 inflammasome plays a key role in responding to pathogens, and endogenous damage and mitochondria are intensively involved in inflammasome activation. The NLRP3 inflammasome forms multiprotein complexes and its sequential assembly is important for its activation. Here, we show that NLRP3 is ubiquitinated by the mitochondria-associated E3 ligase, MARCH5. Myeloid cell-specific March5 conditional knockout (March5 cKO) mice failed to secrete IL-1ß and IL-18 and exhibited an attenuated mortality rate upon LPS or Pseudomonas aeruginosa challenge. Macrophages derived from March5 cKO mice also did not produce IL-1ß and IL-18 after microbial infection. Mechanistically, MARCH5 interacts with the NACHT domain of NLRP3 and promotes K27-linked polyubiquitination on K324 and K430 residues of NLRP3. Ubiquitination-defective NLRP3 mutants on K324 and K430 residues are not able to bind to NEK7, nor form NLRP3 oligomers leading to abortive ASC speck formation and diminished IL-1ß production. Thus, MARCH5-dependent NLRP3 ubiquitination on the mitochondria is required for NLRP3-NEK7 complex formation and NLRP3 oligomerization. We propose that the E3 ligase MARCH5 is a regulator of NLRP3 inflammasome activation on the mitochondria.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Camundongos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-18/metabolismo , Ubiquitinação , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Caspase 1/metabolismo
3.
FASEB J ; 38(2): e23407, 2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38197598

RESUMO

This study investigated the role of the axis involving chemokine receptor 6 (CCR6) and its ligand chemokine (C-C motif) ligand 20 (CCL20) in acute kidney disease (AKD) using an ischemia-reperfusion injury (IRI) model. The model was established by clamping the unilateral renal artery pedicle of C57BL/6 mice for 30 min, followed by evaluation of CCL20/CCR6 expression at 4 weeks post-IRI. In vitro studies were conducted to examine the effects of hypoxia and H2 O2 -induced oxidative stress on CCL20/CCR6 expression in kidney tissues of patients with AKD and chronic kidney disease (CKD). Tubular epithelial cell apoptosis was more severe in C57BL/6 mice than in CCL20 antibody-treated mice, and CCR6, NGAL mRNA, and IL-8 levels were higher under hypoxic conditions. CCL20 blockade ameliorated apoptotic damage in a dose-dependent manner under hypoxia and reactive oxygen species injury. CCR6 expression in IRI mice indicated that the disease severity was similar to that in patients with the AKD phenotype. Morphometry of CCL20/CCR6 expression revealed a higher likelihood of CCR6+ cell presence in CKD stage 3 patients than in stage 1-2 patients. Kidney tissues of patients with CKD frequently contained CCL20+ cells, which were positively correlated with interstitial inflammation. CCL20/CCR6 levels were increased in fibrotic kidneys at 4 and 8 weeks after 5/6 nephrectomy. These findings suggest that modulating the CCL20/CCR6 pathway is a potential therapeutic strategy for managing the progression of AKD to CKD.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Ligantes , Rim , Células Epiteliais , Artéria Renal , Hipóxia , Receptores CCR6/genética , Quimiocina CCL20/genética
4.
EMBO J ; 39(21): e105139, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32935379

RESUMO

NF-κB essential modulator (NEMO) is a key regulatory protein that functions during NF-κB- and interferon-mediated signaling in response to extracellular stimuli and pathogen infections. Tight regulation of NEMO is essential for host innate immune responses and for maintenance of homeostasis. Here, we report that the E3 ligase MARCH2 is a novel negative regulator of NEMO-mediated signaling upon bacterial or viral infection. MARCH2 interacted directly with NEMO during the late phase of infection and catalyzed K-48-linked ubiquitination of Lys326 on NEMO, which resulted in its degradation. Deletion of MARCH2 resulted in marked resistance to bacterial/viral infection, along with increased innate immune responses both in vitro and in vivo. In addition, MARCH2-/- mice were more susceptible to LPS challenge due to massive production of cytokines. Taken together, these findings provide new insight into the molecular regulation of NEMO and suggest an important role for MARCH2 in homeostatic control of innate immune responses.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinas/metabolismo , Animais , Linhagem Celular , Feminino , Deleção de Genes , Humanos , Imunidade Inata/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , NF-kappa B/metabolismo , Transdução de Sinais/genética , Transcriptoma , Ubiquitina-Proteína Ligases/genética , Ubiquitinação
5.
J Virol ; 97(11): e0079523, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37902401

RESUMO

IMPORTANCE: African swine fever virus (ASFV), the only known DNA arbovirus, is the causative agent of African swine fever (ASF), an acutely contagious disease in pigs. ASF has recently become a crisis in the pig industry in recent years, but there are no commercially available vaccines. Studying the immune evasion mechanisms of ASFV proteins is important for the understanding the pathogenesis of ASFV and essential information for the development of an effective live-attenuated ASFV vaccines. Here, we identified ASFV B175L, previously uncharacterized proteins that inhibit type I interferon signaling by targeting STING and 2'3'-cGAMP. The conserved B175L-zf-FCS motif specifically interacted with both cGAMP and the R238 and Y240 amino acids of STING. Consequently, this interaction interferes with the interaction of cGAMP and STING, thereby inhibiting downstream signaling of IFN-mediated antiviral responses. This novel mechanism of B175L opens a new avenue as one of the ASFV virulent genes that can contribute to the advancement of ASFV live-attenuated vaccines.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Interferon Tipo I , Proteínas de Membrana , Nucleotídeos Cíclicos , Suínos , Proteínas Virais , Animais , Febre Suína Africana/imunologia , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/química , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/imunologia , Vírus da Febre Suína Africana/patogenicidade , Interferon Tipo I/antagonistas & inibidores , Interferon Tipo I/imunologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Nucleotídeos Cíclicos/antagonistas & inibidores , Nucleotídeos Cíclicos/metabolismo , Suínos/imunologia , Suínos/virologia , Vacinas Atenuadas/imunologia , Proteínas Virais/metabolismo , Vacinas Virais/imunologia , Interações entre Hospedeiro e Microrganismos
6.
J Med Virol ; 96(3): e29523, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38483060

RESUMO

Tight control of the type I interferon (IFN) signaling pathway is critical for maintaining host innate immune responses, and the ubiquitination and deubiquitination of signaling molecules are essential for signal transduction. Deubiquitinase ubiquitin-specific protein 19 (USP19) is known to be involved in deubiquitinating Beclin1, TRAF3, and TRIF for downregulation of the type I IFN signaling. Here, we show that SIAH1, a cellular E3 ubiquitin ligase that is involved in multicellular pathway, is a potent positive regulator of virus-mediated type I IFN signaling that maintains homeostasis within the antiviral immune response by targeting USP19. In the early stages of virus infection, stabilized SIAH1 directly interacts with the USP19 and simultaneously mediates K27-linked ubiquitination of 489, 490, and 610 residues of USP19 for proteasomal degradation. Additionally, we found that USP19 specifically interacts with MAVS and deubiquitinates K63-linked ubiquitinated MAVS for negative regulation of type I IFN signaling. Ultimately, we identified that SIAH1-mediated degradation of USP19 reversed USP19-mediated deubiquitination of MAVS, Beclin1, TRAF3, and TRIF, resulting in the activation of antiviral immune responses. Taken together, these findings provide new insights into the molecular mechanism of USP19 and SIAH1, and suggest a critical role of SIAH1 in antiviral immune response and homeostasis.


Assuntos
Interferon Tipo I , Ubiquitina , Humanos , Ubiquitina/metabolismo , Fator 3 Associado a Receptor de TNF/genética , Proteína Beclina-1 , Ubiquitinação , Imunidade Inata , Interferon Tipo I/metabolismo , Enzimas Desubiquitinantes/genética , Enzimas Desubiquitinantes/metabolismo , Proteínas Adaptadoras de Transporte Vesicular , Endopeptidases/genética , Endopeptidases/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-38441681

RESUMO

BACKGROUND: This study aims to assess the effectiveness of the preoperative flash visual evoked potential (VEP) test in predicting postoperative visual acuity for monocular mature cataract cases when compared to the contralateral normal eye. METHODS: The study included 60 patients, each with a monocular mature cataract diagnosis, who underwent preoperative flash VEP testing showing no pattern VEP response. Subsequently, phacoemulsification was performed. The relationship between the flash VEP test latency values (P1, N2, P2) and amplitude value (N2-P2), and the degree of visual acuity recovery 3 months post-cataract surgery, was evaluated using the LogMAR scale. Furthermore, a linear regression analysis was conducted to explore the connection between preoperative flash VEP components and postoperative visual acuity. RESULTS: The average age of the patients was 65.4 ± 13.6 years, with a range of 43 to 87 years. The study included 36 males and 24 females. A significant disparity in visual acuity was observed between the preoperative and 3-month postoperative stages (p < 0.001). The preoperative flash VEP test for mature cataracts revealed significant delays in P1, N2, and P2 latency, as well as a reduction in N2-P2 amplitude potential when compared to the contralateral normal eye (p < 0.001). Notably, delayed P2 latency and reduced N2-P2 amplitude potential were particularly indicative of poor visual acuity prognosis after cataract surgery in the multiple regression analysis (p < 0.05). The N2-P2 amplitude potential was the important value that exhibited statistically significant results, with an area under the curve (AUC) of 80% sensitivity and 88% specificity, using a cutoff value of 6.07 µV. CONCLUSIONS: In cases of monocular mature cataract, a reduction in N2-P2 amplitude potential compared to the contralateral normal eye emerged as the most reliable predictor of postoperative visual prognosis following cataract surgery.

8.
Biol Res ; 57(1): 25, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720397

RESUMO

PURPOSE: Prostate cancer (PCa) is a major urological disease that is associated with significant morbidity and mortality in men. LLGL2 is the mammalian homolog of Lgl. It acts as a tumor suppressor in breast and hepatic cancer. However, the role of LLGL2 and the underlying mechanisms in PCa have not yet been elucidated. Here, we investigate the role of LLGL2 in the regulation of epithelial-mesenchymal transition (EMT) in PCa through autophagy in vitro and in vivo. METHODS: PC3 cells were transfected with siLLGL2 or plasmid LLGL2 and autophagy was examined. Invasion, migration, and wound healing were assessed in PC3 cells under autophagy regulation. Tumor growth was evaluated using a shLLGL2 xenograft mouse model. RESULTS: In patients with PCa, LLGL2 levels were higher with defective autophagy and increased EMT. Our results showed that the knockdown of LLGL2 induced autophagy flux by upregulating Vps34 and ATG14L. LLGL2 knockdown inhibits EMT by upregulating E-cadherin and downregulating fibronectin and α-SMA. The pharmacological activation of autophagy by rapamycin suppressed EMT, and these effects were reversed by 3-methyladenine treatment. Interestingly, in a shLLGL2 xenograft mouse model, tumor size and EMT were decreased, which were improved by autophagy induction and worsened by autophagy inhibition. CONCLUSION: Defective expression of LLGL2 leads to attenuation of EMT due to the upregulation of autophagy flux in PCa. Our results suggest that LLGL2 is a novel target for alleviating PCa via the regulation of autophagy.


Assuntos
Autofagia , Transição Epitelial-Mesenquimal , Neoplasias da Próstata , Animais , Humanos , Masculino , Camundongos , Autofagia/fisiologia , Autofagia/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Inativação Gênica , Camundongos Nus , Neoplasias da Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
9.
J Orthop Sci ; 29(2): 615-620, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36842894

RESUMO

BACKGROUND: In hallux valgus surgery, it is essential to accurately assess the position of the sesamoids both pre- and postoperatively. Weight-bearing foot anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views are radiographic methods used to assess the medial sesamoid position. This study aimed to measure the medial sesamoid position and evaluate the correlation between these three radiographic methods. METHODS: This retrospective study comprised 59 feet from 49 patients who underwent hallux valgus surgery. The mean age of patients was 54.6 (range, 22-70) years. We took preoperative and postoperative measurements using the weight-bearing anteroposterior, tangential sesamoid, and semi-weight-bearing computed tomography axial views to assess the medial sesamoid position. RESULTS: The mean grades of the medial sesamoid position preoperatively and 6 months postoperatively were 2.5 and 0.8, 1.6 and 0.4, and 1.3 and 0.3 points based on the anteroposterior, tangential sesamoid, and computed tomography axial views, respectively (P < 0.001). Preoperatively, there was a strong positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.645) and anteroposterior and computed tomography axial views (P < 0.001, r = 0.468). In contrast, the tangential sesamoid and anteroposterior views showed a weak positive correlation (P = 0.03, r = 0.283). Six months postoperatively, there was a positive correlation between the computed tomography axial and tangential sesamoid views (P < 0.001, r = 0.473), anteroposterior and computed tomography axial views (P < 0.001, r = 0.470), and tangential sesamoid and anteroposterior views (P < 0.001, r = 0.480). CONCLUSIONS: We observed that the anteroposterior view exhibited a higher degree of medial sesamoid position displacement than the computed tomography axial and tangential sesamoid views. For the preoperative evaluation of the medial sesamoid position, the correlation between the computed tomography axial and tangential sesamoid views was stronger than that between the tangential sesamoid and anteroposterior views. However, all three views showed strong correlations postoperatively.


Assuntos
Hallux Valgus , Hallux , Ossos do Metatarso , Ossos Sesamoides , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Hallux Valgus/diagnóstico por imagem , Hallux Valgus/cirurgia , Estudos Retrospectivos , Ossos Sesamoides/diagnóstico por imagem , Ossos Sesamoides/cirurgia , Tomografia Computadorizada por Raios X , Cuidados Pré-Operatórios , Ossos do Metatarso/cirurgia
10.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38396775

RESUMO

DP96R of African swine fever virus (ASFV), also known as uridine kinase (UK), encodes a virulence-associated protein. Previous studies have examined DP96R along with other genes in an effort to create live attenuated vaccines. While experiments in pigs have explored the impact of DP96R on the pathogenicity of ASFV, the precise molecular mechanism underlying this phenomenon remains unknown. Here, we describe a novel molecular mechanism by which DP96R suppresses interferon regulator factor-3 (IRF3)-mediated antiviral immune responses. DP96R interacts with a crucial karyopherin (KPNA) binding site within IRF3, disrupting the KPNA-IRF3 interaction and consequently impeding the translocation of IRF3 to the nucleus. Under this mechanistic basis, the ectopic expression of DP96R enhances the replication of DNA and RNA viruses by inhibiting the production of IFNs, whereas DP96R knock-down resulted in higher IFNs and IFN-stimulated gene (ISG) transcription during ASFV infection. Collectively, these findings underscore the pivotal role of DP96R in inhibiting IFN responses and increase our understanding of the relationship between DP96R and the virulence of ASFV.


Assuntos
Vírus da Febre Suína Africana , Fator Regulador 3 de Interferon , Animais , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/patogenicidade , Interferons/metabolismo , Suínos , Proteínas Virais/metabolismo , Virulência , Fatores de Virulência/genética , Fator Regulador 3 de Interferon/metabolismo , Humanos , Interferon Tipo I/metabolismo
11.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791177

RESUMO

Acute rejection (AR) is critical for long-term graft survival in kidney transplant recipients (KTRs). This study aimed to evaluate the efficacy of the integrated risk score of omics-based biomarkers in predicting AR in KTRs. This prospective, randomized, controlled, multicenter, pilot study enrolled 40 patients who recently underwent high-immunologic-risk kidney transplantation (KT). Five omics biomarkers were measured, namely, blood mRNA (three-gene signature), urinary exosomal miRNA (three-gene signature), urinary mRNA (six-gene signature), and two urinary exosomal proteins (hemopexin and tetraspanin-1) at 2 weeks and every 4 weeks after KT for 1 year. An integrated risk score was generated by summing each biomarker up. The biomarker group was informed about the integrated risk scores and used to adjust immunosuppression, but not the control group. The outcomes were graft function and frequency of graft biopsy. Sixteen patients in the biomarker group and nineteen in the control group completed the study. The mean estimated glomerular filtration rate after KT did not differ between the groups. Graft biopsy was performed in two patients (12.5%) and nine (47.4%) in the biomarker and control groups, respectively, with the proportion being significantly lower in the biomarker group (p = 0.027). One patient (6.3%) in the biomarker group and two (10.5%) in the control group were diagnosed with AR, and the AR incidence did not differ between the groups. The tacrolimus trough level was significantly lower in the biomarker group than in the control group at 1 year after KT (p = 0.006). Integrated omics biomarker monitoring may help prevent unnecessary or high-complication-risk biopsy and enables tailored immunosuppression by predicting the risk of AR in KTRs.


Assuntos
Biomarcadores , Rejeição de Enxerto , Transplante de Rim , Humanos , Transplante de Rim/efeitos adversos , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/sangue , Masculino , Feminino , Biomarcadores/sangue , Biomarcadores/urina , Projetos Piloto , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto , Fatores de Risco , Sobrevivência de Enxerto , MicroRNAs/sangue , MicroRNAs/genética , Medição de Risco
12.
J Virol ; 96(15): e0102222, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35861515

RESUMO

African swine fever virus (ASFV) is a highly pathogenic swine DNA virus with high mortality that causes African swine fever (ASF) in domestic pigs and wild boars. For efficient viral infection, ASFV has developed complex strategies to evade key components of antiviral innate immune responses. However, the immune escape mechanism of ASFV remains unclear. Upon ASFV infection, cyclic GMP-AMP (2',3'-cGAMP) synthase (cGAS), a cytosolic DNA sensor, recognizes ASFV DNA and synthesizes the second messenger 2',3'-cGAMP, which triggers interferon (IFN) production to interfere with viral replication. In this study, we demonstrated a novel immune evasion mechanism of ASFV EP364R and C129R, which blocks cellular cyclic 2',3'-cGAMP-mediated antiviral responses. ASFV EP364R and C129R with nuclease homology inhibit IFN-mediated responses by specifically interacting with 2',3'-cGAMP and exerting their phosphodiesterase (PDE) activity to cleave 2',3'-cGAMP. Particularly notable is that ASFV EP364R had a region of homology with the stimulator of interferon genes (STING) protein containing a 2',3'-cGAMP-binding motif and point mutations in the Y76S and N78A amino acids of EP364R that impaired interaction with 2',3'-cGAMP and restored subsequent antiviral responses. These results highlight a critical role for ASFV EP364R and C129R in the inhibition of IFN responses and could be used to develop ASFV live attenuated vaccines. IMPORTANCE African swine fever (ASF) is a highly contagious hemorrhagic disease in domestic pigs and wild boars caused by African swine fever virus (ASFV). ASF is a deadly epidemic disease in the global pig industry, but no drugs or vaccines are available. Understanding the pathogenesis of ASFV is essential to developing an effective live attenuated ASFV vaccine, and investigating the immune evasion mechanisms of ASFV is crucial to improve the understanding of its pathogenesis. In this study, for the first time, we identified the EP364R and C129R, uncharacterized proteins that inhibit type I interferon signaling. ASFV EP364R and C129R specifically interacted with 2',3'-cGAMP, the mammalian second messenger, and exerted phosphodiesterase activity to cleave 2',3'-cGAMP. In this study, we discovered a novel mechanism by which ASFV inhibits IFN-mediated antiviral responses, and our findings can guide the understanding of ASFV pathogenesis and the development of live attenuated ASFV vaccines.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Vírus da Febre Suína Africana , Evasão da Resposta Imune , Proteínas de Membrana , Nucleotídeos Cíclicos , Nucleotidiltransferases , Transdução de Sinais , Proteínas Virais , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/imunologia , Vírus da Febre Suína Africana/metabolismo , Animais , Interferons/antagonistas & inibidores , Interferons/imunologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Nucleotídeos Cíclicos/imunologia , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Sus scrofa/virologia , Suínos , Vacinas Atenuadas , Proteínas Virais/metabolismo , Vacinas Virais
13.
Am J Kidney Dis ; 82(3): 290-299.e1, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36965829

RESUMO

RATIONALE & OBJECTIVE: Metformin has been recommended for some patients with advanced chronic kidney disease. However, the value of metformin in kidney transplant recipients (KTRs) with pretransplant diabetes mellitus (DM) or posttransplant DM is uncertain. We investigated the clinical effects of metformin in KTRs. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: A total of 1,995 KTRs with diabetes from 6 tertiary referral centers in the Republic of Korea. EXPOSURE: Metformin usage was defined as the use of metformin for>90 days after kidney transplantation; 1,193 KTRs were metformin users, and 802 KTRs did not use metformin. Changing usage of metformin among those exposed for >90 days was also characterized. OUTCOME: Primary outcomes were all-cause mortality and death-censored graft failure (DCGF). Secondary outcomes were biopsy-proven acute rejection (BPAR) and lactic acidosis events. ANALYTICAL APPROACH: Survival analyses were conducted using multivariable Cox regression and competing risk analyses using Fine and Gray models. Changes in metformin use over time were modeled using a time-varying covariate. Metformin usage, mean daily dose, and hemoglobin A1c (HbA1c) changes were considered in the landmark analysis to address time-varying confounding. RESULTS: Metformin use was associated with a lower risk of DCGF (adjusted hazard ratio [AHR], 0.47 [95% CI, 0.23-0.96], P=0.038); there was no significant association with all-cause mortality (AHR, 0.94 [95% CI, 0.32-2.76], P=0.915) or BPAR (AHR 0.98 [95% CI, 0.62-1.54], P=0.942). In the subgroup analysis, metformin usage was associated with a reduced risk of all-cause mortality and a lower risk of DCGF for both pretransplantation DM and posttransplant DM groups. Metformin usage was associated with a lower risk of BPAR in the posttransplant DM group, although it was less effective in the pretransplantation DM group. There was no confirmed case of metformin-associated lactic acidosis (MALA) in the present cohort. A higher dose of metformin was correlated with lower risks of DCGF and BPAR. LIMITATIONS: Data on newer antidiabetic drugs such as SGLT2 inhibitors are limited, and there is potential limited generalizability to other populations. CONCLUSIONS: Metformin usage may benefit KTRs, as evidenced by its association with a reduced risk of DCGF and the absence of MALA events. Randomized controlled trials are needed to validate these observational findings.


Assuntos
Acidose Láctica , Diabetes Mellitus , Transplante de Rim , Metformina , Humanos , Metformina/uso terapêutico , Estudos Retrospectivos , Transplantados , Fatores de Risco
14.
J Nutr ; 153(8): 2380-2388, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37302714

RESUMO

BACKGROUND: Vitamin B12 involves several physiological functions, and malabsorption is reported with medication use. OBJECTIVES: Studies have reported an inverse association between the use of metformin or acid-lowering agents (ALAs), such as proton pump inhibitors, histamine 2 receptor antagonists, and blood vitamin B12 concentration, because of malabsorption. The concomitant use of these medications is underreported. We sought to examine these associations in a cohort of Boston-area Puerto Rican adults. METHODS: This analysis was conducted within the Boston Puerto Rican Health Study (BPRHS), an ongoing longitudinal cohort that enrolled 1499 Puerto Rican adults aged 45-75 y at baseline. Our study comprised 1428, 1155, and 782 participants at baseline, wave2 (2.2 y from baseline), and wave3 (6.2 y from baseline), respectively. Covariate-adjusted linear and logistic regression was used to examine the association between baseline medication use and vitamin B12 concentration or deficiency (vitamin B12 <148 pmol/L or methylmalonic acid >271 nmol/L), and long-term medication use (continuous use for ∼6.2 y) and wave3 vitamin B12 concentration and deficiency. Sensitivity analyses were done to examine these associations in vitamin B12 supplement users. RESULTS: At baseline, we observed an association between metformin use (ß = -0.069; P = 0.03) and concomitant ALA and metformin use (ß = -0.112; P = 0.02) and vitamin B12 concentration, but not a deficiency. We did not observe associations between ALA, proton pump inhibitors, or histamine 2 receptor antagonists, individually, with vitamin B12 concentration or deficiency. CONCLUSIONS: These results suggest an inverse relationship between metformin, concomitant ALA, metformin use, and serum vitamin B12 concentration.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Deficiência de Vitamina B 12 , Adulto , Humanos , Metformina/uso terapêutico , Vitamina B 12 , Inibidores da Bomba de Prótons/efeitos adversos , Histamina , Antagonistas dos Receptores H2 da Histamina/efeitos adversos , Hipoglicemiantes/uso terapêutico
15.
Clin Nephrol ; 100(4): 165-176, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37577767

RESUMO

AIMS: This study aimed to examine the association between food insecurity and the prevalence of chronic diseases among older adults in South Korea and to compare the findings with data from the United States (US). MATERIALS AND METHODS: We analyzed data from the Korea National Health and Nutrition Examination Survey (KNHANES) V (2010 - 2012) and VI (2013 - 2015) and 4 years (2012 - 2015) of food security questionnaire data. The data of 46,189 National Health and Nutrition Examination Survey participants (1999 - 2016) were subjected to propensity score-matched (PSM) analysis. RESULTS: We included 7,914 individuals from the KNHANES. In the older group (age > 65 years), no differences were observed in the prevalence of hypertension, diabetes, chronic kidney disease (CKD), and metabolic syndrome across the income groups. Income, education, and food security had no impact on hypertension, diabetes, and CKD prevalence in the multivariate logistic analysis after PSM. CKD was not associated with food insecurity (odds ratio (OR), 1.26; 95% confidence interval (CI), 0.94 - 1.26) in the final model using the KNHANES data; however, the U.S. NHANES data showed that an increased risk of hypertension was associated with food insecurity (OR, 1.27; 95% CI, 1.04 - 1.55). CONCLUSION: As per the U.S. NHANES data, food insecurity was associated with a high prevalence of hypertension, while as per the South Korean KNHANES data, food insecurity was not found to be associated with CKD, indicating divergent relationships between food insecurity and chronic diseases in the two countries. Further research is needed to explore these differences.


Assuntos
Diabetes Mellitus , Hipertensão , Insuficiência Renal Crônica , Humanos , Estados Unidos , Idoso , Inquéritos Nutricionais , Fatores de Risco , Abastecimento de Alimentos , Rim , Doença Crônica , Diabetes Mellitus/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/etiologia , Hipertensão/epidemiologia , Hipertensão/complicações
16.
BMC Ophthalmol ; 23(1): 343, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537533

RESUMO

BACKGROUND: To evaluate the efficacy of 1% and 2% rebamipide clear solution in the treatment of dry eye disease (DED). METHODS: Two hundred twenty patients with DED were randomly assigned to one of three groups: the 1% rebamipide, 2% rebamipide, or placebo (eye drops containing the same ingredients, except for the active components). Each eye drop was instilled four times daily for 12 weeks. Changes in tear film break-up time (TBUT), corneal and conjunctival staining score, Schirmer 1 test, and the Ocular Surface Disease Index (OSDI) from baseline to 12-week visit between the study groups were compared for efficacy assessment. RESULTS: The mean age of study patients was 43.8±14.2 years. The 1% and 2% rebamipide groups showed greater improvement in TBUT (1.99±1.87 and 2.02±2.21 s) at 12 weeks from baseline than the placebo group (1.25±2.93 s). The 2% rebamipide group showed greater improvement in the corneal staining score (- 3.15±2.00) at 12 weeks from baseline than the placebo group (- 2.85±1.80). The 1% and 2% rebamipide groups showed improvement in Schirmer 1 test (1.27±3.86 and 1.50±4.14 mm) at 12 weeks of treatment, but not the placebo group (0.55±2.99 mm). Both the rebamipide groups and the placebo group showed significantly improved OSDI after treatment for 12 weeks; however, there was no significant difference among the three groups. CONCLUSIONS: 1% and 2% rebamipide clear solutions are an effective therapeutic option for improving TBUT and tear volume, and stabilizing the corneal staining score in DED.


Assuntos
Síndromes do Olho Seco , Quinolonas , Humanos , Adulto , Pessoa de Meia-Idade , Síndromes do Olho Seco/tratamento farmacológico , Quinolonas/uso terapêutico , Soluções Oftálmicas , Alanina/uso terapêutico , Lágrimas
17.
BMC Med Ethics ; 24(1): 18, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882795

RESUMO

BACKGROUND: This study aimed to identify the healthcare providers' experience and perspectives toward end-of-life care decisions focusing on end-of-life discussion and physician's order of life-sustaining treatment documentation in Korea which are major parts of the Life-Sustaining Treatment Act. METHODS: A cross-sectional survey was conducted using a questionnaire developed by the authors. A total of 474 subjects-94 attending physicians, 87 resident physicians, and 293 nurses-participated in the survey, and the data analysis was performed in terms of frequency, percentage, mean and standard deviation using the SPSS 24.0 program. RESULTS: Study results showed that respondents were aware of terminal illness and physician's order of life-sustaining treatment in Korea well enough except for some details. Physicians reported uncertainty in terminal state diagnosis and disease trajectory as the most challenging. Study participants regarded factors (related to relationships and communications) on the healthcare providers' side as the major impediment to end-of-life discussion. Study respondents suggested that simplification of the process and more staff are required to facilitate end-of-life discussion and documentation. CONCLUSION: Based on the study results, adequate education and training for better end-of-life discussion are required for future practice. Also, a simple and clear procedure for completing a physician's order of life-sustaining treatment in Korea should be prepared and legal and ethical advice would be required. Since the enactment of the Life-Sustaining Treatment Act, several revisions already have been made including disease categories, thus continuous education to update and support clinicians is also called for.


Assuntos
Médicos , Assistência Terminal , Humanos , Estudos Transversais , Morte , República da Coreia
18.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834109

RESUMO

Melanogenesis, the intricate process of melanin synthesis, is central to skin pigmentation and photoprotection and is regulated by various signaling pathways and transcription factors. To develop potential skin-whitening agents, we used B16F1 melanoma cells to investigate the inhibitory effects of anhydrous alum on melanogenesis and its underlying molecular mechanisms. Anhydrous alum (KAl(SO4)2) with high purity (>99%), which is generated through the heat-treatment of hydrated alum (KAl(SO4)2·12H2O) at 400 °C, potentiates a significant reduction in melanin content without cytotoxicity. Anhydrous alum downregulates the master regulator of melanogenesis, microphthalmia-associated transcription factor (MITF), which targets key genes involved in melanogenesis, thereby inhibiting α-melanocyte-stimulating hormone (α-MSH)-induced melanogenesis. Phosphorylation of the cAMP response element-binding protein, which acts as a co-activator of MITF gene expression, is attenuated by anhydrous alum, resulting in compromised MITF transcription. Notably, anhydrous alum promoted extracellular signal-regulated kinase phosphorylation, leading to the impaired nuclear localization of MITF. Overall, these results demonstrated the generation and mode of action of anhydrous alum in B16F1 cells, which constitutes a promising option for cosmetic or therapeutic use.


Assuntos
Melaninas , alfa-MSH , Melaninas/metabolismo , alfa-MSH/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Fator de Transcrição Associado à Microftalmia/genética , Fator de Transcrição Associado à Microftalmia/metabolismo , Linhagem Celular Tumoral
19.
Am J Physiol Renal Physiol ; 322(5): F553-F572, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35311382

RESUMO

Signal transducer and activator of transcription 3 (STAT3) is a pivotal mediator of IL-6-type cytokine signaling. However, the roles of its full-length and truncated isoforms in acute kidney injury (AKI) and its transition to chronic kidney disease (CKD) remain elusive. Herein, the role of STAT3 isoforms in the AKI-to-CKD transition was characterized using an ischemia-reperfusion injury (IRI) mouse model. The STAT3 inhibitor Stattic was administered to C57BL/6 mice 3 h before IRI. Intrarenal cytokine expression was quantified using real-time PCR and FACS. The effect of Stattic on human tubular epithelial cells cultured under hypoxic conditions was also evaluated. Phosphorylated (p)STAT3 isoforms were detected by Western blot analysis. Stattic treatment attenuated IRI-induced tubular damage and inflammatory cytokine/chemokine expression while decreasing macrophage infiltration and fibrosis in mouse unilateral IRI and unilateral ureteral obstruction models. Similarly, in vitro STAT3 inhibition downregulated fibrosis and apoptosis in 72-h hypoxia-induced human tubular epithelial cells and reduced pSTAT3α-mediated inflammation. Moreover, pSTAT3 expression was increased in human acute tubular necrosis and CKD tissues. STAT3 activation is associated with IRI progression, and STAT3α may be a significant contributor. Hence, STAT3 may affect the AKI-to-CKD transition, suggesting a novel strategy for AKI management with STAT3 inhibitors.NEW & NOTEWORTHY We found that IRI increased expression of STAT3 in murine kidneys, along with inflammation markers. Through the investigation of the role of STAT3 in the AKI-to-CKD transition mechanism using mouse unilateral IRI and unilateral ureteral obstruction models and 24- or 72-h hypoxic induction of primary cultured human tubular epithelial cells, we found that STAT3 could affect the AKI-to-CKD transition. We also observed different degrees of expression in STAT3 isoforms in these processes.


Assuntos
Injúria Renal Aguda , Insuficiência Renal Crônica , Traumatismo por Reperfusão , Obstrução Ureteral , Injúria Renal Aguda/patologia , Animais , Citocinas/metabolismo , Fibrose , Inflamação/metabolismo , Rim/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Insuficiência Renal Crônica/patologia , Traumatismo por Reperfusão/patologia , Fator de Transcrição STAT3/metabolismo , Obstrução Ureteral/patologia
20.
PLoS Pathog ; 16(11): e1009057, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33232374

RESUMO

VP1, a pivotal capsid protein encoded by the foot-and-mouth disease virus (FMDV), plays an important role in receptor-mediated attachment and humoral immune responses. Previous studies show that amino acid changes in the VP1 protein of cell culture-adapted strains of FMDV alter the properties of the virus. In addition, FMDV VP1 modulates host IFN signal transduction. Here, we examined the ability of cell culture-adapted FMDV VP1(83K) and wild-type FMDV VP1(83E) to evade host immunity by blocking mitochondrial antiviral signaling protein (MAVS)/TNF Receptor Associated Factor 3 (TRAF3) mediated cellular innate responses. Wild-type FMDV VP1(83E) interacted specifically with C-terminal TRAF3-binding site within MAVS and this interaction inhibited binding of TRAF3 to MAVS, thereby suppressing interferon-mediated responses. This was not observed for cell culture-adapted FMDV VP1(83K). Finally, chimeric FMDV harboring VP1(83K) showed very low pathogenicity in pigs. Collectively, these data highlight a critical role of VP1 with respect to suppression of type-I IFN pathway and attenuation of FMDV by the E83K mutation in VP1.


Assuntos
Proteínas do Capsídeo/genética , Vírus da Febre Aftosa/genética , Febre Aftosa/virologia , Transdução de Sinais , Substituição de Aminoácidos , Animais , Proteínas do Capsídeo/metabolismo , Febre Aftosa/imunologia , Vírus da Febre Aftosa/imunologia , Imunidade Inata , Interferons/metabolismo , Mutação , Ligação Proteica , Fator 3 Associado a Receptor de TNF/genética , Fator 3 Associado a Receptor de TNF/metabolismo
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