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1.
Antioxidants (Basel) ; 11(5)2022 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35624761

RESUMO

Drug-induced liver injury (DILI) development is commonly associated with acetaminophen (APAP) overdose, where glutathione scavenging leads to mitochondrial dysfunction and hepatocyte death. DILI is a severe disorder without effective late-stage treatment, since N-acetyl cysteine must be administered 8 h after overdose to be efficient. Ammonia homeostasis is altered during liver diseases and, during DILI, it is accompanied by decreased glycine N-methyltransferase (GNMT) expression and S-adenosylmethionine (AdoMet) levels that suggest a reduced methionine cycle. Anti-miR-873-5p treatment prevents cell death in primary hepatocytes and the appearance of necrotic areas in liver from APAP-administered mice. In our study, we demonstrate a GNMT and methionine cycle activity restoration by the anti-miR-873-5p that reduces mitochondrial dysfunction and oxidative stress. The lack of hyperammoniemia caused by the therapy results in a decreased urea cycle, enhancing the synthesis of polyamines from ornithine and AdoMet and thus impacting the observed recovery of mitochondria and hepatocyte proliferation for regeneration. In summary, anti-miR-873-5p appears to be an effective therapy against APAP-induced liver injury, where the restoration of GNMT and the methionine cycle may prevent mitochondrial dysfunction while activating hepatocyte proliferative response.

2.
Cell Death Dis ; 12(6): 555, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050139

RESUMO

Dysregulation of miRNAs is a hallmark of cancer, modulating oncogenes, tumor suppressors, and drug responsiveness. The multi-kinase inhibitor sorafenib is one of the first-line drugs for advanced hepatocellular carcinoma (HCC), although the outcome for treated patients is heterogeneous. The identification of predictive biomarkers and targets of sorafenib efficacy are sorely needed. Thus, selected top upregulated miRNAs from the C19MC cluster were analyzed in different hepatoma cell lines compared to immortalized liver human cells, THLE-2 as control. MiR-518d-5p showed the most consistent upregulation among them. Thus, miR-518d-5p was measured in liver tumor/non-tumor samples of two distinct cohorts of HCC patients (n = 16 and n = 20, respectively). Circulating miR-518d-5p was measured in an independent cohort of HCC patients receiving sorafenib treatment (n = 100), where miR-518d-5p was analyzed in relation to treatment duration and patient's overall survival. In vitro and in vivo studies were performed in human hepatoma BCLC3 and Huh7 cells to analyze the effect of miR-518d-5p inhibition/overexpression during the response to sorafenib. Compared with healthy individuals, miR-518d-5p levels were higher in hepatic and serum samples from HCC patients (n = 16) and in an additional cohort of tumor/non-tumor paired samples (n = 20). MiR-518d-5p, through the inhibition of c-Jun and its mitochondrial target PUMA, desensitized human hepatoma cells and mouse xenograft to sorafenib-induced apoptosis. Finally, serum miR-518d-5p was assessed in 100 patients with HCC of different etiologies and BCLC-stage treated with sorafenib. In BCLC-C patients, higher serum miR-518d-5p at diagnosis was associated with shorter sorafenib treatment duration and survival. Hence, hepatic miR-518d-5p modulates sorafenib resistance in HCC through inhibition of c-Jun/PUMA-induced apoptosis. Circulating miR-518d-5p emerges as a potential lack of response biomarker to sorafenib in BCLC-C HCC patients.


Assuntos
Neoplasias Hepáticas/genética , MicroRNAs/antagonistas & inibidores , Mitocôndrias/metabolismo , Animais , Apoptose , Morte Celular , Feminino , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus
3.
Sensors (Basel) ; 18(7)2018 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-29932444

RESUMO

Lubricant and hydraulic fluid ageing impacts the performance of the machines, gears, transmissions or automatisms where they are being used. This manuscript describes the work accomplished for bringing an innovative measurement concept for analysing the physical- chemical properties of these fluids, to a real industrial product ready to be integrated into different industrial equipment. The steps taken to deal with uncertainties and evolving requirements while progressing in the sensor development are described, covering the stages of theoretical formulation of the problem, optical and fluidic simulations, sensor prototype development and tests. The sensor working principle is based on a combination of transmittance and diffuse reflectance photonic inspection of the fluid sample that is collected in a microcavity through a standard hydraulic fitting. Photonics, electronics, micro-mechanics, fluidics, data processing and analysis has been merged with a deep knowledge in the lubricant degradation process to develop a sensor solution that is able to measure the Oil Degradation Index, Oil Oxidation, Acid Number, Ruler and Membrane Patch Colorimetry data from an inservice lubricating oil sample. The photonic micro sensor presented here offers a powerful tool that operates directly immersed in the fluid, at an economic cost and compacted size for inline oil degradation monitoring.

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