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1.
J Lipid Res ; 65(3): 100517, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38342436

RESUMO

The last step of ex novo ceramide biosynthesis consists of the conversion of dihydroceramide into ceramide catalyzed by sphingolipid Δ4-desaturase DEGS1. DEGS1 variants were found to be responsible for heterogeneous clinical pictures belonging to the family of hypomyelinating leukodystrophies. To investigate the mechanisms making such variants pathogenic, we designed a procedure for the efficient detection of desaturase activity in vitro using LC-MS/MS and prepared a suitable cell model knocking out DEGS1 in HEK-293T cells through CRISPR-Cas9 genome editing (KO-DES-HEK). Transfecting KO-DES-HEK cells with DEGS1 variants, we found that their transcripts were all overexpressed as much as the WT transcripts, while the levels of cognate protein were 40%-80% lower. In vitro desaturase activity was lost by many variants except L175Q and N255S, which maintain a catalytic efficiency close to 12% of the WT enzyme. Metabolic labeling of KO-DES-HEK with deuterated palmitate followed by LC-MS/MS analysis of the formed sphingolipids revealed that the ceramide/dihydroceramide and sphingomyelin/dihydrosphingomyelin ratios were low and could be reverted by the overexpression of WT DEGS1 as well as of L175Q and N255S variants, but not by the overexpression of all other variants. Similar analyses performed on fibroblasts from a patient heterozygous for the N255S variant showed very low variant DEGS1 levels and a low ratio between the same unsaturated and saturated sphingolipids formed upon metabolic labeling, notwithstanding the residual activity measured at high substrate and homogenate protein concentrations. We conclude that loss of function and reduced protein levels are both relevant in disease pathogenesis.


Assuntos
Ceramidas , Oxirredutases , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida , Ceramidas/metabolismo , Esfingolipídeos/genética , Esfingolipídeos/metabolismo , Ácidos Graxos Dessaturases/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-37677138

RESUMO

This pilot case series histologically and histometrically investigated the influence of implant surface hydrophilicity on early osseointegration and peri-implant bone formation around simultaneously grafted immediate implants. Core biopsies of the hydrophilic test (SLAactive®) or hydrophobic control (SLA®) implants immediately placed in maxillary molar extraction sites and simultaneously grafted with mineralized cancellous bone allograft (MCBA) obtained at 3 weeks post-placement were histometrically compared for bone to implant contact, the quantity of graft material, new bone formation, tissue reaction, and inflammatory scores. Test implants showed a more pronounced implant-bone apposition, peri-implant bone formation and bone aggregate than control implants. Trabecular bone formation and maturation were also qualitatively advanced around test implants. These results indicate that the implant surface bone graft combination may affect peri-implant bone formation.

3.
Sci Rep ; 13(1): 7766, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173330

RESUMO

Cholangiocarcinoma (CCA) is a rare cancer characterized by a global increasing incidence. Extracellular vesicles (EV) contribute to many of the hallmarks of cancer through transfer of their cargo molecules. The sphingolipid (SPL) profile of intrahepatic CCA (iCCA)-derived EVs was characterized by liquid chromatography-tandem mass spectrometry analysis. The effect of iCCA-derived EVs as mediators of inflammation was assessed on monocytes by flow cytometry. iCCA-derived EVs showed downregulation of all SPL species. Of note, poorly-differentiated iCCA-derived EVs showed a higher ceramide and dihydroceramide content compared with moderately-differentiated iCCA-derived EVs. Of note, higher dihydroceramide content was associated with vascular invasion. Cancer-derived EVs induced the release of pro-inflammatory cytokines in monocytes. Inhibition of synthesis of ceramide with Myriocin, a specific inhibitor of the serine palmitoyl transferase, reduced the pro-inflammatory activity of iCCA-derived EVs, demonstrating a role for ceramide as mediator of inflammation in iCCA. In conclusion, iCCA-derived EVs may promote iCCA progression by exporting the excess of pro-apoptotic and pro-inflammatory ceramides.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Vesículas Extracelulares , Humanos , Monócitos , Ceramidas/análise , Inflamação , Colangiocarcinoma/patologia , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Vesículas Extracelulares/química
4.
PLoS One ; 17(4): e0266740, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35413071

RESUMO

The aim of the present study is to detect the presence of SARS-CoV-2 of patients affected by COVID-19 in olfactory mucosa (OM), sampled with nasal brushing (NB) and biopsy, and to assess whether a non-invasive procedure, such as NB, might be used as a large-scale procedure for demonstrating SARS-CoV-2 presence in olfactory neuroepithelium. Nasal brushings obtained from all the COVID-19 patients resulted positive to SARS-CoV-2 immunocytochemistry while controls were negative. Double immunofluorescence showed that SARS-CoV-2 positive cells included supporting cells as well as olfactory neurons and basal cells. OM biopsies showed an uneven distribution of SARS-CoV-2 positivity along the olfactory neuroepithelium, while OM from controls were negative. SARS-CoV-2 was distinctively found in sustentacular cells, olfactory neurons, and basal cells, supporting what was observed in NB. Ultrastructural analysis of OM biopsies showed SARS-CoV-2 viral particles in the cytoplasm of sustentacular cells. This study shows the presence of SARS-CoV-2 at the level of the olfactory neuroepithelium in patients affected by COVID-19. For the first time, we used NB as a rapid non-invasive tool for assessing a potential neuroinvasion by SARS-CoV-2 infection.


Assuntos
COVID-19 , SARS-CoV-2 , Biópsia , COVID-19/diagnóstico , Humanos , Mucosa Olfatória/patologia
5.
Antioxidants (Basel) ; 10(1)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467745

RESUMO

Existing therapies for Parkinson's disease (PD) are only symptomatic. As erythropoietin (EPO) is emerging for its benefits in neurodegenerative diseases, here, we test the protective effect driven by EPO in in vitro (SH-SY5Y cells challenged by MPP+) and in vivo (C57BL/6J mice administered with MPTP) PD models. EPO restores cell viability in both protective and restorative layouts, enhancing the dopaminergic recovery. Specifically, EPO rescues the PD-induced damage to mitochondria, as shown by transmission electron microscopy, Mitotracker assay and PINK1 expression. Moreover, EPO promotes a rescue of mitochondrial respiration while markedly enhancing the glycolytic rate, as shown by the augmented extracellular acidification rate, contributing to elevated ATP levels in MPP+-challenged cells. In PD mice, EPO intrastriatal infusion markedly improves the outcome of behavioral tests. This is associated with the rescue of dopaminergic markers and decreased neuroinflammation. This study demonstrates cellular and functional recovery following EPO treatment, likely mediated by the 37 Kda isoform of the EPO-receptor. We report for the first time, that EPO-neuroprotection is exerted through restoring ATP levels by accelerating the glycolytic rate. In conclusion, the redox imbalance and neuroinflammation associated with PD may be successfully treated by EPO.

6.
Biomedicines ; 8(12)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33352880

RESUMO

AIMS: A considerable proportion of patients affected by coronavirus respiratory disease (COVID-19) develop cardiac injury. The viral impact in cardiomyocytes deserves, however, further investigations, especially in asymptomatic patients. METHODS: We investigated for SARS-CoV-2 presence and activity in heart tissues of six consecutive COVID-19 patients deceased from respiratory failure showing no signs of cardiac involvement and with no history of heart disease. Cardiac autopsy samples were collected within 2 h after death, and then analysed by digital PCR, Western blot, immunohistochemistry, immunofluorescence, RNAScope, and transmission electron microscopy assays. RESULTS: The presence of SARS-CoV-2 into cardiomyocytes was invariably detected in all assays. A variable pattern of cardiomyocyte injury was observed, spanning from absence of cell death and subcellular alterations hallmarks, to intracellular oedema and sarcomere ruptures. In addition, we found active viral transcription in cardiomyocytes, by detecting both sense and antisense SARS-CoV-2 spike RNA. CONCLUSIONS: In this autopsy analysis of patients with no clinical signs of cardiac involvement, the presence of SARS-CoV-2 in cardiomyocytes has been detected, determining variable patterns of intracellular damage. These findings suggest the need for cardiologic surveillance in surviving COVID-19 patients not displaying a cardiac phenotype.

7.
Retina ; 40(12): 2403-2409, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32195788

RESUMO

PURPOSE: 1) To investigate morphologic and histochemical characteristics of an epiretinal fibrosis removed in an Argus II-implanted eye; 2) to evaluate the Argus II function before and after the fibrosis removal, and 3) to compare morphologic and functional data. METHODS: Fibrosis, which developed between the Argus II prosthesis and the retina two years after implant, was surgically removed. Its morphologic and histochemical characteristics were evaluated both in light and transmission electron microscopy, with special stains and immunohistochemistry. The Argus II function was evaluated during the follow-up before surgical removal and 1 month later. RESULTS: Fibrosis was successfully removed. It was composed of a fibrotic tissue with spindle cells arranged in nodular aggregates with a symmetric distribution, mixed with an inflammatory infiltrate. Extra- and intracellular, irregular, small iron particles were found and confirmed ultrastructural characterization with degenerative cellular changes. The repositioned Argus II restored, and its function was partially nearly to normal values 1 month after surgery. CONCLUSION: Fibrosis can develop between the Argus II and the retina with increasing reduced function. Morphologic characteristics of the removed fibrosis suggested a pathogenesis based on an inflammatory process involved in a foreign body reaction with progressing connective tissue deposition leading to sclerosis. Adequate clinical follow-up is critical to successful removal of the fibrosis with reactivation of the Argus II function.


Assuntos
Membrana Epirretiniana/patologia , Procedimentos Cirúrgicos Oftalmológicos , Retina/patologia , Retinose Pigmentar/cirurgia , Próteses Visuais/efeitos adversos , Membrana Epirretiniana/etiologia , Membrana Epirretiniana/cirurgia , Fibrose/etiologia , Fibrose/patologia , Fibrose/cirurgia , Seguimentos , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Implantação de Prótese , Retina/cirurgia , Retinose Pigmentar/fisiopatologia , Tomografia de Coerência Óptica
8.
Int J Mol Sci ; 20(23)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775364

RESUMO

In chronic kidney disease (CKD), the first cause of mortality is cardiovascular disease induced mainly by vascular calcification (VC). Recently, iron-based phosphate binders have been proposed in advanced CKD to treat hyperphosphatemia. We studied the effect of iron citrate (iron) on the progression of calcification in high-phosphate (Pi) calcified VSMC. Iron arrested further calcification when added on days 7-15 in the presence of high Pi (1.30 ± 0.03 vs 0.61 ± 0.02; OD/mg protein; day 15; Pi vs Pi + Fe, p < 0.01). We next investigated apoptosis and autophagy. Adding iron to high-Pi-treated VSMC, on days 7-11, decreased apoptotic cell number (17.3 ± 2.6 vs 11.6 ± 1.6; Annexin V; % positive cells; day 11; Pi vs Pi + Fe; p < 0.05). The result was confirmed thorough analysis of apoptotic nuclei both in VSMCs and aortic rings treated on days 7-15 (3.8 ± 0.2 vs 2.3 ± 0.3 and 4.0 ± 0.3 vs 2.2 ± 0.2; apoptotic nuclei; arbitrary score; day 15; Pi vs Pi + Fe; VSMCs and aortic rings; p < 0.05). Studying the prosurvival axis GAS6/AXL, we found that iron treatment on days 9-14 counteracted protein high-Pi-stimulated down-regulation and induced its de novo synthesis. Moreover, iron added on days 9-15 potentiated autophagy, as detected by an increased number of autophagosomes with damaged mitochondria and an increase in autophagic flux. Highlighting the effect of iron on apoptosis, we demonstrated its action in blocking the H2O2-induced increase in calcification added both before high Pi treatment and when the calcification was already exacerbated. In conclusion, we demonstrate that iron arrests further high Pi-induced calcium deposition through an anti-apoptotic action and the induction of autophagy on established calcified VSMC.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia , Cálcio/toxicidade , Compostos Férricos/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Fosfatos/toxicidade , Calcificação Vascular/tratamento farmacológico , Animais , Células Cultivadas , Músculo Liso Vascular/patologia , Ratos , Calcificação Vascular/induzido quimicamente , Calcificação Vascular/patologia
9.
Int J Cardiol ; 297: 94-103, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31619363

RESUMO

BACKGROUND: High serum phosphate (Pi) levels strongly associate with cardiovascular morbidity and mortality in chronic kidney disease (CKD) patients with vascular calcification playing a major role in the pathogenesis of related cardiovascular disease. High-Pi challenged vascular smooth muscle cells (VSMCs) undergo simil-osteoblastic transformation and actively deposit calcium-phosphate crystals. Iron-based Pi-binders are used to treat hyperphosphatemia in CKD patients. METHODS: In this study, we investigated the direct effect of iron citrate on extracellular matrix (ECM) modification induced by high-Pi, following either prophylactic or therapeutic approach. RESULTS: Iron prophylactically prevents and therapeutically blocks high-Pi induced calcification. Masson's staining highlights the changes of muscular ECM that after high-Pi stimulation becomes fibrotic and which modifications are prevented or partially reverted by iron. Interestingly, iron preserves glycogen granules and either prevents or partially reverts the formation of non-glycogen granules induced by high-Pi. In parallel, iron addition is able to either prevent or block the high-Pi induced acid mucin deposition. Iron inhibited calcification also by preventing exosome osteo-chondrogenic shift by reducing phosphate load (0,61 ±â€¯0.04vs0,45 ±â€¯0.05, PivsPi + Fe, p < 0,05, nmol Pi/mg protein) and inducing miRNA 30c (0.62 ± 0.05vs3.07 ±â€¯0.62; PivsPi + Fe, p < 0.01, relative expression). Studying aortic rings, we found that iron significantly either prevents or reverts the high-Pi induced collagen deposition and the elastin decrease, preserving elastin structure (0.7 ± 0.1 vs 1.2 ± 0.1; Pi vs Pi + Fe, p < 0.05, elastin mRNA relative expression). CONCLUSIONS: Iron directly either prevents or partially reverts the high-Pi induced osteo-chondrocytic shift of ECM. The protection of muscular nature of VSMC ECM may be one of the mechanisms elucidating the anti-calcific effect of iron.


Assuntos
Condrócitos/efeitos dos fármacos , Hiperfosfatemia/complicações , Compostos de Ferro/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Calcificação Vascular/etiologia , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Condrócitos/patologia , Ácido Cítrico/farmacologia , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/patologia , Hiperfosfatemia/patologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Ratos , Calcificação Vascular/patologia
10.
Acta Ophthalmol ; 97(4): e559-e567, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30585429

RESUMO

PURPOSE: Subthreshold micropulse laser (SMPL) has been increasingly used for the treatment of different retinal and choroidal macular disorders. However, the exact mechanisms of action have not yet been clearly defined. Therefore, we aimed to examine the role of SMPL treatment in the modulation of oxidant/antioxidant systems, apoptosis and autophagy in the mice eyes. METHODS: A specific laser contact lens for retina was positioned on the cornea of 40 mice (20 young and 20 old) in order to focus the laser on the eye fundus for SMPL treatment. Within 6 months, 20 animals received one treatment only, whereas the others were treated three times. Eye specimens underwent histological analysis and were used for thiobarbituric acid reactive substances (TBARS) and glutathione (GSH) quantification, as well as for the superoxide dismutase 1 (SOD1) and the selenoprotein thioredoxin reductase 1 (TrxR1) expression evaluation. Western blot was performed for nitric oxide synthase (NOS) subtypes detection and to examine changes in apoptotic/autophagy proteins expression. RESULTS: SMPL treatment reduced TBARS and increased GSH and SOD1 in the mice eyes. It also reduced cytochrome c, caspase 3 expression and activity and cleaved caspase 9, and increased Beclin 1, p62 and LC3ß. The effects were more relevant in the elderly animals. CONCLUSION: Our results showed that SMPL therapy restored the oxidant/antioxidant balance within retinal layers and modulated programmed forms of cell death. Further studies may confirm these data and could evaluate their relevance in clinical practice.


Assuntos
Antioxidantes/metabolismo , Fotocoagulação a Laser/métodos , Lasers Semicondutores/uso terapêutico , Oxidantes/metabolismo , Estresse Oxidativo , Retina/cirurgia , Doenças Retinianas/cirurgia , Animais , Autofagia , Morte Celular , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Retina/metabolismo , Retina/patologia , Doenças Retinianas/metabolismo , Doenças Retinianas/patologia , Tomografia de Coerência Óptica/métodos
11.
Front Physiol ; 9: 289, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29636700

RESUMO

Background: Hypoxia represents both an outcome of cardiopulmonary diseases and a trigger for severe pulmonary complications as pulmonary hypertension. Because nitric oxide (NO) is a critical mediator in the development of pulmonary hypertension, the modulators of its downstream function may become target of pharmacological interventions aimed at alleviating the impact of this condition. Here, we investigate the effects of an early administration of phosphodiesterase-5 inhibitor in rats where pulmonary artery hypertension was induced by chronic exposure to hypoxia. Methods: Rats were divided into three groups: normoxic control, hypoxic with no treatments (2 weeks breathing an atmosphere containing 10% oxygen), and hypoxic treated with sildenafil (1.4 mg/Kg per day in 0.3 mL i.p.). After sacrifice, hearts and lungs were removed and harvested for analyses. Results: Sildenafil reduced hypoxia-induced right ventricle hypertrophy without effects in lung hypertrophy, and blunted the increase in right ventricle pressure without effects on left ventricle pressure. Furthermore, the NO-producing systems (i.e., the phosphorylation of the endothelial isoforms of NO synthase that was measured in both myocardial and lung tissues), and the blood NO stores (i.e., the plasma level of nitrates and nitrites) were up-regulated by sildenafil. We did not find significant effects of sildenafil on weight and hemoglobin concentration. Morphological analysis in lung biopsies revealed that 2-week hypoxia increased the frequency of small pulmonary vessels leaving large vessels unaffected. Finally, ultrastructural analysis showed that sildenafil down-regulated the hypoxia-induced increase in the thickness of the pulmonary basal lamina. Conclusions: In this model of pulmonary hypertension, sildenafil contrasts the negative effects of hypoxia on pulmonary vascular and right ventricle remodeling. This action does not only encompass the canonical vasomodulatory effect, but involves several biochemical pathways. Although the human pathological model is certainly more complex than that described here (for example, the inflammatory issue), the potential role of phosphodiesterase-5 for long-term treatment, and perhaps prevention, of pulmonary hypertension is worthy of investigation.

12.
Reprod Sci ; 22(7): 838-44, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25544676

RESUMO

Autophagy is an inducible catabolic process by which cells degrade and recycle materials to survive stress, starvation, and hypoxia. The aim of this study was to evaluate autophagy at the fetal-maternal interface, to assess autophagy involvement during the early phase of human gestation, and to explore autophagic modification in case of early abnormal pregnancy outcome. Specimens were collected from first-trimester normal gestations undergoing legal termination of pregnancy and first-trimester sporadic spontaneous miscarriages. Autophagy was studied in villous and decidual samples by transmission electron microscopy, immunohistochemistry, immunofluorescence, and Western blotting. Autophagy markers were found in cytotrophoblast, syncytiotrophoblast, extravillous trophoblast, and decidual stromal cells. Autophagy is physiologically involved in early normal gestation. Compared with normal pregnancy, spontaneous miscarriage presents an increase in autophagy expression in villous specimens due to an increment in concentration of autophagic vacuole in syncytiotrophoblast, suggesting a cytoprotective mechanism of the cells to respond to microenvironmental challenge.


Assuntos
Aborto Espontâneo/metabolismo , Autofagia/fisiologia , Vilosidades Coriônicas/metabolismo , Decídua/metabolismo , Primeiro Trimestre da Gravidez/metabolismo , Aborto Espontâneo/patologia , Adulto , Vilosidades Coriônicas/patologia , Decídua/patologia , Feminino , Humanos , Troca Materno-Fetal/fisiologia , Gravidez , Adulto Jovem
13.
Muscles Ligaments Tendons J ; 3(3): 122-31, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24367771

RESUMO

We characterized the effect of ciprofloxacin (CPX) in cultured human tenocytes by morphological and molecular methods. Collagen type I and III mRNA and protein levels were unaffected, but lysyl hydroxylase 2b mRNA levels progressively decreased after CPX administration. MMP-1 protein levels significantly increased after 20 µg/ml CPX administration but remained unmodified at the higher dose, whilst MMP-2 activity was unchanged. Tissue inhibitor of MMP (TIMP-1) gene expression decreased after CPX treatment, whilst TIMP-2 and transforming growth factor-ß1 gene expression, the cytoskeleton arrangement, and cytochrome c expression remained unmodified. Secreted Protein Acidic and Rich in Cysteine mRNA and protein levels remained almost unchanged, whilst N-cadherin mRNA levels resulted significantly down-regulated and connexin 43 gene expression tended to decrease after CPX administration. The CPX-induced decreased ability to cross-link collagen and decreased TIMP-1 levels, possibly leading to higher activity of MMPs in ECM degradation, together with the down-regulation of N-cadherin and connexin 43 are consistent with a reduced ability to maintain tissue homeostasis, possibly making the tendon more susceptible to rupture.

14.
Muscles Ligaments Tendons J ; 3(1): 42-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23885344

RESUMO

We studied the effect of spasticity-induced overload on tendons from the gracilis and semitendinosus muscles from cerebral palsy (CP) and healthy subjects (CT) stained with haematoxylineosin, Sirius red and Alcian blue. Vascularity was also characterized using an anti-CD34 antibody. Light microscopy analysis of haematoxylin-eosin stained sections revealed that the overall structure of tendons was maintained, characterized by parallel and slightly wavy collagen fibers in both CT and CP tendons. However, hypercellularity, cell rounding, increased vascularity and lipoid degeneration were observed in CP samples. Sirius red stained collagen fibers were more evident in CP tendons, suggesting an increased collagen content induced by spasticity. Alcian blue staining revealed an overall increase of glycosaminoglycans in CP tendons as observed in tendinopathy. Our results suggest that CP-induced spasticity may be considered as a chronic, persisting and repetitive loading of tendons, inducing ECM remodeling as adaptive response to increased functional demand. At the same time, the evidence of some tendinopathic-like markers in CP tendons suggests that the chronic nature of the CP condition could represent a pathologic condition, possibly leading to a transient weakness of the tissue making it more susceptible to damage from cumulative loading until an overt tendinopathy develops.

15.
Anticancer Drugs ; 23(9): 935-46, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22700003

RESUMO

The aim of this study is to characterize the phenotype of pancreatic ductal adenocarcinoma (PDAC) cells in relation to the expression of epithelial-to-mesenchymal transition (EMT) markers and determine whether ukrain, an anticancer drug based on the alkaloids extracted from greater celandine, modulates in vitro the malignant behavior of PDAC cells in order to extend our understanding of its therapeutic potential. Three cell lines (HPAF-II, HPAC, and PL45) were treated with ukrain (5, 10, and 20 µmol/l) for 48 h or left untreated (control). Cell proliferation was assessed by growth curves. Apoptosis was determined by Hoechst nuclear staining and by cytochrome c and caspase-8 expressions. The EMT markers E-cadherin, ß-catenin, and vimentin, as well as actin and tubulin cytoskeletons, were analyzed by immunofluorescence. Interphase and mitotic microtubules as well as abnormal mitotic figures were studied by fluorescence microscopy after tubulin immunolabeling. Ukrain strongly suppressed cell proliferation and induced apoptosis possibly through an extrinsic pathway as cytochrome c immunoreactivity suggested that the integrity of the mitochondria was not affected. Tubulin expression indicated an antiproliferative effect of ukrain on the basis of alterations in mitotic spindle microtubule dynamics, leading to abnormal mitosis. Membranous E-cadherin/ß-catenin immunoreactivity was similarly expressed in control-treated and ukrain-treated cells, although the drug upregulated E-cadherin in cell lysates. Our results suggest that ukrain exerts its chemotherapeutic action on PDAC cells targeting mitotic spindle microtubules, leading to abnormal mitosis and apoptosis, and favoring cell cohesiveness. The differentiated epithelial phenotype of HPAF-II, HPAC, and PL45 cell lines concomitant with a highly invasive potential suggests that further experiments will be necessary to definitively clarify the role of EMT in PDAC progression.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Alcaloides de Berberina/farmacologia , Carcinoma Ductal Pancreático/patologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Microtúbulos/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Fenantridinas/farmacologia , Fuso Acromático/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Caderinas/biossíntese , Carcinoma Ductal Pancreático/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Microtúbulos/patologia , Mitose/efeitos dos fármacos , Índice Mitótico , Neoplasias Pancreáticas/metabolismo , Fenótipo , Fuso Acromático/patologia , Fatores de Tempo , beta Catenina/biossíntese
16.
Anticancer Drugs ; 22(8): 749-62, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21799470

RESUMO

We investigated whether Ukrain modulates the malignant phenotype of clear cell renal cell carcinoma (ccRCC) cells Caki-1, Caki-2, and ACHN treated with four doses (5, 10, 20, and 40 µmol/l) for 24 and 48 h. The epithelial-to-mesenchymal transition markers E-cadherin, ß-catenin, and vimentin were analyzed by immunofluorescence as well as actin and tubulin; matrix metalloproteinase-2 and matrix metalloproteinase-9 activity was analyzed by SDS-zymography, intracellular and secreted SPARC levels by western blot, and cell cycle by flow cytometry. Ukrain did not induce E-cadherin/ß-catenin immunoreactivity at the cell-cell boundary, although it determined the actin cortical expression in Caki-2 and ACHN, and did not affect vimentin organization; however, in some Caki-1 and ACHN cells the perinuclear concentration of vimentin was consistent with its downregulation. Matrix metalloproteinase-2 and matrix metalloproteinase-9 activity was significantly downregulated 48 h after 20 µmol/l Ukrain administration. At this time point, Ukrain significantly decreased migration and invasion, and downregulated SPARC levels in cell supernatants at all doses in Caki-2, and at 20 µmol/l in Caki-1 and ACHN cells. Concomitantly, SPARC was upregulated in all ccRCC cells, suggesting that Ukrain could also affect cell proliferation by cell cycle inhibition, as supported by the cell cycle analysis, as SPARC also acts as a cell cycle inhibitor. Our results suggest that Ukrain may switch the epithelial-to-mesenchymal transition-related phenotype of ccRCC cells, and targets the two major aspects involved in RCC progression, such as tumor invasion/microenvironment remodeling and cell proliferation.


Assuntos
Antineoplásicos/farmacologia , Alcaloides de Berberina/farmacologia , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Fenantridinas/farmacologia , Alcaloides de Berberina/administração & dosagem , Carcinoma de Células Renais/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Renais/patologia , Invasividade Neoplásica , Fenantridinas/administração & dosagem , Fenótipo , Microambiente Tumoral/efeitos dos fármacos
17.
Cells Tissues Organs ; 186(2): 141-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17587787

RESUMO

We studied quantitative changes in mitochondria of perineuronal satellite cell sheaths (SCSs) of rabbit spinal ganglia from young to extremely advanced age (1, 3.6, 6.7 and 8.8 years). The mitochondrial structure did not differ in the four age groups, while mitochondrial size increased progressively and significantly with age. The mean percentage of cytoplasmic volume occupied by mitochondria decreased progressively and significantly from young to old animals. This decrease was mainly due to a progressive and significant reduction in the total mitochondrial volume. Lipofuscin accumulation had a negligible influence on this reduction. These results suggest that the ability of SCSs to produce energy decreases with age and that the reduced ability of spinal ganglion neurons to respond to high energy demands in old age may be in part due to the diminished contribution of perineuronal satellite cells.


Assuntos
Envelhecimento/fisiologia , Gânglios Espinais/fisiologia , Mitocôndrias/fisiologia , Células Satélites Perineuronais/fisiologia , Animais , Citoplasma/fisiologia , Citoplasma/ultraestrutura , Feminino , Gânglios Espinais/crescimento & desenvolvimento , Gânglios Espinais/ultraestrutura , Masculino , Mitocôndrias/ultraestrutura , Tamanho Mitocondrial , Coelhos , Células Satélites Perineuronais/ultraestrutura
18.
BCI ; 8(29): 71-75, jan.-mar. 2001. ilus
Artigo em Português | LILACS, BBO | ID: lil-303936

RESUMO

A Fibromatose Gengival Hereditária (FGH) se caracteriza por um aumento gengival causado por uma produçäo excessiva de fibras colágenas no tecido conjuntivo gengival. Pode ocorrer isoladamente ou associada a alguma síndrome. Este artigo descreve a ocorrência da FGH em quatro membros de uma mesma família. A etiologia, aspectos clínicos, radiográficos e histológicos seräo discutidos. O tratamento cirúrgico, gengivectomias e exodontias, foi realizado sob anestesia local e por quadrantes. Controle pós-operatório de 18 meses foi efetuado


Assuntos
Humanos , Masculino , Feminino , Criança , Adulto , Fibromatose Gengival , Hiperplasia Gengival , Gengivectomia , Cirurgia Bucal
19.
RGO (Porto Alegre) ; 38(5): 379-82, set.-out. 1990. ilus
Artigo em Português | LILACS, BBO | ID: biblio-854714

RESUMO

Os 18 ratos utilizados foram divididos em dois grupos de 9 ratos cada, sendo um controle e outro tratado. Os ratos injetados com vitaminas do complexo B "Roche", com 0,1 ml/dia, intraperitoneal, exibiram, ao exame histológico uma maior substituição da rede de fibrina, e um tecido de granulação mais exuberante e mais colagenizado, com relação aos controles, abreviando destarte a cicatrização das feridas cutâneas


Assuntos
Animais , Ratos , Cicatrização , Complexo Vitamínico B
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