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1.
Metabolism ; 152: 155765, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142958

RESUMO

BACKGROUND AND AIM: The excessive accumulation of lipid droplets (LDs) is a defining characteristic of nonalcoholic fatty liver disease (NAFLD). The interaction between LDs and mitochondria is functionally important for lipid metabolism homeostasis. Exercise improves NAFLD, but it is not known if it has an effect on hepatic LD-mitochondria interactions. Here, we investigated the influence of exercise on LD-mitochondria interactions and its significance in the context of NAFLD. APPROACH AND RESULTS: Mice were fed high-fat diet (HFD) or HFD-0.1 % methionine and choline-deficient diet (MCD) to emulate simple hepatic steatosis or non-alcoholic steatohepatitis, respectively. In both models, aerobic exercise decreased the size of LDs bound to mitochondria and the number of LD-mitochondria contacts. Analysis showed that the effects of exercise on HOMA-IR and liver triglyceride levels were independent of changes in body weight, and a positive correlation was observed between the number of LD-mitochondria contacts and NAFLD severity and with the lipid droplet size bound to mitochondria. Cellular fractionation studies revealed that ATP-coupled respiration and fatty acid oxidation (FAO) were greater in hepatic peridroplet mitochondria (PDM) from HFD-fed exercised mice than from equivalent sedentary mice. Finally, exercise increased FAO and mitofusin-2 abundance exclusively in PDM through a mechanism involving the curvature of mitochondrial membranes and the abundance of saturated lipids. Accordingly, hepatic mitofusin-2 ablation prevented exercise-induced FAO in PDM. CONCLUSIONS: This study demonstrates that aerobic exercise has beneficial effects in murine NAFLD models by lessening the interactions between hepatic LDs and mitochondria, and by decreasing LD size, correlating with a reduced severity of NAFLD. Additionally, aerobic exercise increases FAO in PDM and this process is reliant on Mfn-2 enrichment, which modifies LD-mitochondria communication.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Masculino , Camundongos , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Gotículas Lipídicas/metabolismo , Metabolismo dos Lipídeos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo
2.
ACS Omega ; 7(47): 42752-42762, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467934

RESUMO

Cellular labeling through the use of dyes is of great interest to the biomedical sciences for the characterization of the location and distribution of biomolecules and also for the tracking of the course of biological processes in both health and illness. This paper reports the synthesis, characterization, and subsequent evaluation as metal sensors and cell staining probes of four aza-BODIPY compounds [herein referred to as 7(a-d)]. Compounds 7(b-d) were found to display an outstanding selectivity for Cu(II) because their emission band at 720 nm was progressively quenched by this metal, presenting fluorescence quenching between 75 and 95%. On the other hand, cell imaging studies with pancreatic ß-cells proved that aza-BODIPYs 7a and 7b showed selectivity for the cytoplasm, while 7c and 7d were selective for the cell membrane. Moreover, aza-BODIPY 7b allowed to characterize in a clear way a lipotoxic condition mediated by saturated fatty acids, a critical phenomenon on ß-cell damage associated with diabetes mellitus type II. Taken together, the presented results highlight the obtained aza-BODIPY compounds as selective sensing/staining probes with the potential to be used in the biomedical field.

3.
Turk J Anaesthesiol Reanim ; 50(3): 167-172, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35801321

RESUMO

The pericapsular nerve group block shows promising results in providing pain relief with a potential motor-sparing effect in hip fracture patients. In this narrative review, we analyze the published articles, and we describe the structures achieved when performing the block. We conducted a literature search to identify the articles performing the pericapsular nerve group block, in the adult or paediatric population, from November 1, 2018, to May 15, 2021. Of the 68 selected articles, 38 were considered eligible, including 1 double-blinded randomized comparative trial, 4 observational studies, and 33 case series and case reports. The technique was described in both acute and chronic pain settings, mainly performed as single shot. All studies described effective analgesia. Quadriceps weakness was experienced in some patients. It has been described as easy to perform and has a low rate of complications. It lacks, however, adequately powered randomized controlled trials to assess its clinical value and efficacy.

5.
Med Ultrason ; 22(4): 461-468, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-32905568

RESUMO

The pandemic of COVID-19 requires rapid and easy access to reliable imaging modalities for diagnosis and follow up. Considering the cost-effectiveness of the imaging used, ultrasound is a non-ionizing, portable and bedside imaging modality with a high diagnostic impact in emergencies and intensive care units in pandemics, but it is operator dependent. In our article, we provide a comprehensive review of the role of point-of-care ultrasound in the diagnosis of COVID-19 infection and its impact on the lungs, cardiovascular system, eyes and abdominal organs. Moreover, ultrasound can provide real-time diagnostic and therapeutic interventions, such as the placement of a central catheter and aspiration of pericardial effusion. Awareness of health care professionals in the front-line fighting COVID-19 infection in emergency rooms, clinics, and in intensive care units is important and will help rapid and targeted management decisions.


Assuntos
COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Sistemas Automatizados de Assistência Junto ao Leito , Ultrassonografia/instrumentação , Ultrassonografia/métodos , Humanos , Unidades de Terapia Intensiva , Pandemias
8.
ACS Omega ; 5(10): 5249-5257, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32201814

RESUMO

This study reports the synthesis of thin polymeric films by the layer-by-layer deposition and covalent cross-linking of polyvinyl dimethylazlactone and polyethylene imine, which were functionalized with lauric (12-C), myristic (14-C), and palmitic (16-C) saturated fatty acids, whose high levels in the bloodstream are correlated with insulin resistance and the potential development of type 2 diabetes mellitus. Aiming to assess the effect of the fatty acids on the adhesion and proliferation of Langerhans ß-cells, all prepared films (35 and 35.5 bilayers with and without functionalization with the fatty acids) were characterized in terms of their physical, chemical, and biological properties by a battery of experimental techniques including 1H and 13C NMR, mass spectrometry, attenuated total reflectance-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscopy, cell staining, and confocal laser scanning microscopy among others. In general, the developed films were found to be nanometric, transparent, resistant against manipulation, chemically reactive, and highly cytocompatible. On the other hand, in what the effect of the fatty acids is concerned, palmitic acid was found to impair the proliferation of the cultured ß-cells, contrary to its homologues which did not alter this biological process. In our opinion, the multidisciplinary study presented here might be of interest for the research community working on the development of cytocompatible 2D model substrates for the safe and reproducible characterization of cell responses.

12.
Nanomedicine ; 6(6): 777-85, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20493967

RESUMO

Photodynamic therapy (PDT) has emerged as an alternative and promising noninvasive treatment for cancer. It is a two-step procedure that uses a combination of molecular oxygen, visible light, and photosensitizer (PS) agents; phthalocyanine (Pc) was supported over titanium oxide but has not yet been used for cell inactivation. Zinc phthalocyanine (ZnPc) molecules were incorporated into the porous network of titanium dioxide (TiO(2)) using the sol-gel method. It was prepared from stock solutions of ZnPc and TiO(2). ZnPc-TiO(2) was tested with four cancer cell lines. The characterization of supported ZnPc showed that phthalocyanine is linked by the N-pyrrole to the support and is stable up to 250°C, leading to testing for PDT. The preferential localization in target organelles such as mitochondria or lysosomes could determine the cell death mechanism after PDT. The results suggest that nanoparticulated TiO(2) sensitized with ZnPc is an excellent candidate as sensitizer in PDT against cancer and infectious diseases.


Assuntos
Indóis/química , Compostos Organometálicos/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Titânio/química , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Isoindóis , Luz , Oxigênio , Análise Espectral Raman , Compostos de Zinco
13.
Arthritis Res Ther ; 11(4): R105, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19586548

RESUMO

INTRODUCTION: Cytokines produced by spinal cord glia after peripheral injuries have a relevant role in the maintenance of pain states. Thus, while IL-1beta is overexpressed in the spinal cords of animals submitted to experimental arthritis and other chronic pain models, intrathecal administration of IL-1beta to healthy animals induces hyperalgesia and allodynia and enhances wind-up activity in dorsal horn neurons. METHODS: To investigate the functional contribution of glial cells in the spinal cord nociceptive transmission, the effect of intrathecally administered IL-1beta was studied in both normal and adjuvant-induced arthritic rats with or without glial inhibition. Four weeks after induction of monoarthritis, rats were treated with the glial cell inhibitor propentofylline (10 microg i.t. daily during 10 days) and submitted to a C-fiber-mediated reflex paradigm evoked by single and repetitive (wind-up) electric stimulation. RESULTS: Both the propentofylline treatment and the monoarthritic condition modified the stimulating current required for threshold activation of C reflex responses. Intrathecal IL-1beta increased spinal cord wind-up activity in normal and monoarthritic rats without propentofylline pre-treatment, but resulted in decreased wind-up activity in normal and monoarthritic propentofylline-treated animals. Intrathecal saline did not produce any effect. Thus, glial inactivation reverted into inhibition the excitatory effect of IL-1beta on spinal cord wind-up, irrespective of the normal or monoarthritic condition of rats. CONCLUSIONS: The results suggest that the excitatory effect of nanomolar doses of IL-1beta on spinal wind-up in healthy rats is produced by an unidentified glial mediator, while the inhibitory effects of IL-1beta on wind-up activity in animals with inactivated glia resulted from a direct effect of the cytokine on dorsal horn neurons. The present study failed to demonstrate a differential sensitivity of normal and monoarthritic rats to IL-1beta administration into the spinal cord and to disruption of beta glial function, as both normal and monoarthritic animals changes wind-up activity in the same direction after propentofylline treatment, suggesting that after glial inhibition normal and monoarthritic animals behave similarly relative to the capability of dorsal horn neurons to generate wind-up activity when repeatedly stimulated by C-fibers.


Assuntos
Artrite Experimental/fisiopatologia , Artrite Reumatoide/fisiopatologia , Interleucina-1beta/metabolismo , Neuroglia/metabolismo , Dor/fisiopatologia , Medula Espinal/fisiopatologia , Adjuvantes Imunológicos , Animais , Artrite Experimental/metabolismo , Artrite Reumatoide/metabolismo , Estimulação Elétrica , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Dor/metabolismo , Ratos , Ratos Sprague-Dawley , Reflexo/efeitos dos fármacos , Reflexo/fisiologia , Medula Espinal/metabolismo , Xantinas/farmacologia
14.
Molecules ; 14(5): 1860-8, 2009 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-19471206

RESUMO

Alkylation is a very important chemical reaction which modifies the biological properties of drugs. Quinazolinedione derivatives are of considerable interest due to their wide array of pharmacological properties.We now report application of a practical alkylation procedure to several quinazolinediones, including pelanserine (5f), which shows antihypertensive properties, 1-methyl-3-(2'-phenylethyl)-1H,3H-quinazoline-2,4-dione (1ab) and 1-methyl-3-[2'-(4'-methoxyphenyl)ethyl]-lH,3H-quinazoline-2,4-dione (1ae), which had been isolated from natural sources. The alkylation was optimized using dimethyl and diethyl carbonates under microwave irradiations.


Assuntos
Carbonatos/química , Micro-Ondas , Quinazolinonas/química , Alquilação , Anti-Hipertensivos/química , Estrutura Molecular , Quinazolinas/química
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