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1.
FASEB J ; 37(9): e23124, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37552464

RESUMO

Liver fibrosis results from excessive proliferation of, and collagen production by hepatic stellate cells (HSCs) that is caused by chronic liver injury. No drugs are available to cure liver fibrosis. Hydroxyurea is an anti-proliferative drug that is used in benign and malignant disorders. Here, we studied the effect of hydroxyurea on primary HSCs and its anti-fibrotic effect in the CCl4 mouse model of liver fibrosis. Primary rat HSCs were cultured in the absence or presence of hydroxyurea (0.1-1.0 mmol/L). CCl4 or vehicle was administered to C57BL/6/J mice for 4 weeks, with or without hydroxyurea (100 mg/kg/day) co-treatment. We used real-time cell proliferation analysis, Oil Red O (lipid droplet) staining, immunohistochemistry, Acridine Orange staining (apoptosis), Sytox green staining (necrosis), RT-qPCR, ELISA, and Western Blotting for analysis. Hydroxyurea dose-dependently suppressed lipid droplet-loss and mRNA levels of Col1α1 and Acta2 in transdifferentiating HSCs. In fully-activated HSCs, hydroxyurea dose-dependently attenuated PCNA protein levels and BrdU incorporation, but did not reverse Col1α1 and Acta2 mRNA expression. Hydroxyurea did not induce apoptosis or necrosis in HSCs or hepatocytes. Hydroxyurea suppressed accumulation of desmin-positive HSCs and hepatic collagen deposition after CCl4 treatment. CCl4 -induced regenerative hepatocyte proliferation, Col1α1 and Acta2 mRNA expression and α-SMA protein levels were not affected. This study demonstrates that hydroxyurea inhibits HSC proliferation in vitro and attenuates early development of liver fibrosis in vivo, while preserving hepatocyte regeneration after toxic insults by CCl4. Thus, hydroxyurea may have therapeutic value against liver fibrosis.


Assuntos
Células Estreladas do Fígado , Hidroxiureia , Camundongos , Ratos , Animais , Hidroxiureia/efeitos adversos , Células Estreladas do Fígado/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Necrose/patologia , Colágeno/metabolismo , Proliferação de Células , RNA Mensageiro/genética , Tetracloreto de Carbono/toxicidade
2.
J Cell Physiol ; 238(10): 2293-2303, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37555553

RESUMO

Liver fibrosis is the response of the liver to chronic liver inflammation. The communication between the resident liver macrophages (Kupffer cells [KCs]) and hepatic stellate cells (HSCs) has been mainly viewed as one-directional: from KCs to HSCs with KCs promoting fibrogenesis. However, recent studies indicated that HSCs may function as a hub of intercellular communications. Therefore, the aim of the present study was to investigate the role of HSCs on the inflammatory phenotype of KCs. Primary rat HSCs and KCs were isolated from male Wistar rats. HSCs-derived conditioned medium (CM) was harvested from different time intervals (Day 0-2: CM-D2 and Day 5-7: CM-D7) during the activation of HSCs. Extracellular vesicles (EVs) were isolated from CM by ultracentrifugation and evaluated by nanoparticle tracking analysis and western blot analysis. M1 and M2 markers of inflammation were measured by quantitative PCR and macrophage function by assessing phagocytic capacity. CM-D2 significantly induced the inflammatory phenotype in KCs, but not CM-D7. Neither CM-D2 nor CM-D7 affected the phagocytosis of KCs. Importantly, the proinflammatory effect of HSCs-derived CM is mediated via EVs released from HSCs since EVs isolated from CM mimicked the effect of CM, whereas EV-depleted CM lost its ability to induce a proinflammatory phenotype in KCs. In addition, when the activation of HSCs was inhibited, HSCs produced less EVs. Furthermore, the proinflammatory effects of CM and EVs are related to activating Toll-like receptor 4 (TLR4) in KCs. In conclusion, HSCs at an early stage of activation induce a proinflammatory phenotype in KCs via the release of EVs. This effect is absent in CM derived from HSCs at a later stage of activation and is dependent on the activation of TLR4 signaling pathway.

3.
J Cell Biochem ; 124(6): 808-817, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37042199

RESUMO

Activation of hepatic stellate cells (HSC) is a key event in the initiation of liver fibrosis. Activated HSCs proliferate and secrete excessive amounts of extracellular matrix (ECM), disturbing liver architecture and function, leading to fibrosis and eventually cirrhosis. Collagen is the most abundant constituent of ECM and proline is the most abundant amino acid of collagen. Arginine is the precursor in the biosynthetic pathway of proline. Arginine is the exclusive substrate of both nitric oxide synthase (NOS) and arginase. NOS is an M1 (proinflammatory) marker of macrophage polarization whereas arginase-1 (Arg1) is an M2 (profibrogenic) marker of macrophage polarization. Differential expression of NOS and Arg1 has not been studied in HSCs yet. To identify the expression profile of arginine catabolic enzymes during HSC activation and to investigate their role in HSC activation, primary rat HSCs were cultured-activated for 7 days and expression of iNOS and Arg1 were investigated. Nor-NOHA was used as a specific and reversible arginase inhibitor. During HSC activation, iNOS expression decreased whereas Arg1 expression increased. Inhibition of Arg1 in activated HSCs efficiently inhibited collagen production but not cell proliferation. HSC activation is accompanied by a switch of arginine catabolism from iNOS to Arg1. Inhibition of Arg1 decreases collagen synthesis. Therefore, we conclude that Arg1 can be a therapeutic target for the inhibition of liver fibrogenesis.


Assuntos
Arginase , Células Estreladas do Fígado , Ratos , Animais , Células Estreladas do Fígado/metabolismo , Arginase/genética , Arginase/metabolismo , Cirrose Hepática/metabolismo , Colágeno/metabolismo , Arginina
4.
BMC Vet Res ; 15(1): 23, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630483

RESUMO

BACKGROUND: Bovine Viral Diarrhea Virus (BVDV) is associated with gastrointestinal, respiratory and reproductive diseases of livestock across the world that causes continuous economic losses in the cattle industry. This virus can establish a persistent infection (PI) in calves after the fetal infection, making BVDV positive catle carriers and primary reservoirs which will constantly transmit the virus to healthy and new-born animals. For this reason, the detection of the PI animals in herds is the first line of prevention of the viral infection. RESULTS: In this study, PI animals were detected in five different regions of Colombia through RT-PCR techniques and confirmed by sequencing. BVDV genotypes were determined using one fragment of the 5'UTR. It was found a 7% BVDV prevalence in animals and 22% in farms; and genotype 1 was identified as a single genotype for all of the samples. All samples were BVDV 1a. CONCLUSION: This is the first report in Colombia with higher prevalence rates compared with other places in the world, turned out to be of great importance for the ranchers, the vaccine producers and animal health control parties.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/epidemiologia , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Colômbia/epidemiologia , Vírus da Diarreia Viral Bovina/classificação , Feminino , Masculino , Filogenia , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/veterinária
5.
J Trauma Nurs ; 24(5): 326-334, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28885525

RESUMO

The objective of this research was to study the possible relationship between the consumption of dicoumarinic agents (understanding the consumption of acenocoumarol as regulated and monitored anticoagulation) and the mortality rate in people older than 65 years undergoing a hip fracture (HF) intervention. It was a retrospective, observational and descriptive study. Nine hundred fifty-seven patients were included who underwent an intervention for HF between the years 2012 and 2014 in a third-level hospital. Patients took acenocoumarol (16.1%), which compared with nonanticoagulated patients took longer in receiving intervention, they remained hospitalized for more days, and they presented greater mortality within the first year after the intervention. Likewise, those who presented greater risk according to the classification system used by the American Society of Anesthesiologists (ASA) to estimate the risk of anesthesia for the different states of the patients who were anticoagulated also suffered greater mortality. The next factors increased the mortality in the first year: advanced age, delayed surgery, male sex, need for transfusion, high international normalized ratio, consumption of acenocoumarol, and a high ASA risk. We concluded the consumption of acenocoumarol increased the risk of mortality within the first year after surgery in 1.3 of possible cases. Other risk factors that also independently increased the risk of mortality included advanced age, male sex, delayed surgery, the need for transfusions, and surgical risk (for high levels in the ASA classification).


Assuntos
Anticoagulantes/efeitos adversos , Causas de Morte , Fixação Interna de Fraturas/métodos , Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , Acenocumarol/administração & dosagem , Acenocumarol/efeitos adversos , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Estudos de Coortes , Feminino , Seguimentos , Fixação Interna de Fraturas/mortalidade , Avaliação Geriátrica , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/tratamento farmacológico , Humanos , Tempo de Internação , Masculino , Valores de Referência , Estudos Retrospectivos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Resultado do Tratamento
6.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 167020, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38244390

RESUMO

Liver sinusoidal endothelial cells (LSECs) play a crucial role in maintaining liver microcirculation and exchange of nutrients in the liver and are thought to be involved in the pathogenesis of metabolic dysfunction-associated steatotic liver disease (MASLD). The activation of hepatic stellate cells (HSCs) and Kupffer cells (KCs) has been considered to be responsible for the onset of liver fibrosis and the aggravation of liver injury. However, the paracrine regulatory effects of LSECs in the development of MASLD, in particular the role of LSEC-derived extracellular vesicles (EVs) remains unclear. Therefore, the aim of the present study was to investigate the influence of LSEC-derived EVs on HSCs and KCs. Primary rat LSECs, HSCs and KCs were isolated from male Wistar rats. LSEC-derived EVs were isolated from conditioned medium by ultracentrifugation and analyzed by nanoparticle tracking analysis, and expression of specific markers. LSEC-derived EVs reduced the expression of activation markers in activated HSCs but did not affect quiescent HSCs. Also, LSEC-derived EVs suppressed proliferation of activated HSCs activation, as assessed by Xcelligence and BrdU assay. LSEC-derived EVs also increased the expression of inflammatory genes in HSCs that normally are lowly expression during their activation. In contrast, EVs decreased the expression of inflammatory genes in activated KCs. In summary, our results suggest that LSEC-derived EVs may attenuate the fibrogenic phenotype of activated HSCs and the inflammatory phenotype of KCs. Our results show promise for LSEC-derived EVs as therapeutic moieties to treat MASLD. In addition, these EVs might prove of diagnostic value.


Assuntos
Vesículas Extracelulares , Células de Kupffer , Ratos , Animais , Masculino , Células de Kupffer/metabolismo , Células Estreladas do Fígado/metabolismo , Células Endoteliais/metabolismo , Ratos Wistar , Fígado/metabolismo
7.
Cell Cycle ; 23(6): 629-644, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38836592

RESUMO

In chronic liver injury, quiescent hepatic stellate cells (HSCs) transdifferentiate into activated myofibroblast-like cells and produce large amounts of extracellular matrix components, e.g. collagen type 1. Cellular senescence is characterized by irreversible cell-cycle arrest, arrested cell proliferation and the acquisition of the senescence-associated secretory phenotype (SASP) and reversal of HSCs activation. Previous studies reported that H2S prevents induction of senescence via its antioxidant activity. We hypothesized that inhibition of endogenous H2S production induces cellular senescence and reduces activation of HSCs. Rat HSCs were isolated and culture-activated for 7 days. After activation, HSCs treated with H2S slow-releasing donor GYY4137 and/or DL-propargylglycine (DL-PAG), an inhibitor of the H2S-producing enzyme cystathionine γ-lyase (CTH), as well as the PI3K inhibitor LY294002. In our result, CTH expression was significantly increased in fully activated HSCs compared to quiescent HSCs and was also observed in activated stellate cells in a in vivo model of cirrhosis. Inhibition of CTH reduced proliferation and expression of fibrotic markers Col1a1 and Acta2 in HSCs. Concomitantly, DL-PAG increased the cell-cycle arrest markers Cdkn1a (p21), p53 and the SASP marker Il6. Additionally, the number of ß-galactosidase positive senescent HSCs was increased. GYY4137 partially restored the proliferation of senescent HSCs and attenuated the DL-PAG-induced senescent phenotype. Inhibition of PI3K partially reversed the senescence phenotype of HSCs induced by DL-PAG. Inhibition of endogenous H2S production reduces HSCs activation via induction of cellular senescence in a PI3K-Akt dependent manner. Our results show that cell-specific inhibition of H2S could be a novel target for anti-fibrotic therapy via induced cell senescence.


Assuntos
Alcinos , Senescência Celular , Glicina , Células Estreladas do Fígado , Sulfeto de Hidrogênio , Morfolinas , Compostos Organotiofosforados , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Animais , Senescência Celular/efeitos dos fármacos , Morfolinas/farmacologia , Glicina/análogos & derivados , Glicina/farmacologia , Alcinos/farmacologia , Compostos Organotiofosforados/farmacologia , Ratos , Masculino , Cistationina gama-Liase/metabolismo , Proliferação de Células/efeitos dos fármacos , Cromonas/farmacologia , Colágeno Tipo I/metabolismo , Ratos Sprague-Dawley , Fosfatidilinositol 3-Quinases/metabolismo , Células Cultivadas , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fenótipo Secretor Associado à Senescência , Proteína Supressora de Tumor p53/metabolismo
8.
Methods Mol Biol ; 2669: 79-109, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37247056

RESUMO

Hepatic stellate cells (HSCs) are the key effector cells in liver fibrosis. They are the main producers of excessive amounts of extracellular matrix components during fibrogenesis and therefore a potential target for the treatment of liver fibrosis. Induction of senescence in HSCs may be a promising strategy to slow down, stop, or even reverse fibrogenesis. Senescence is a complex and heterogeneous process linked to fibrosis and cancer, but the exact mechanism and relevant markers can be cell-type dependent. Therefore, many markers of senescence have been proposed, and many methods to detect senescence have been developed. In this chapter, we review relevant methods and biomarkers to detect cellular senescence in hepatic stellate cells.


Assuntos
Células Estreladas do Fígado , Células de Kupffer , Humanos , Senescência Celular , Cirrose Hepática , Pesquisa , Fígado
9.
Hum Immunol ; 84(9): 484-491, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37380553

RESUMO

NRAMP1 and VDR gene polymorphisms have been variably associated with susceptibility to tuberculosis (TB) amongst populations having different genetic background. NRAMP1 and VDR gene variants' association with susceptibility to active infection by Mycobacterium tuberculosis (Mtb) was analyzed in the Warao Amerindian population, an ethnic population from Venezuela's Orinoco delta region. Genomic DNA was extracted from individuals with and without TB to evaluate genetic polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Four NRAMP1 gene polymorphisms were analyzed: D543N (rs17235409), 3' UTR (rs17235416), INT4 (rs3731865), and 274C/T (rs2276631), and one VDR gene polymorphism: FokI (rs2228570). The results showed that the genotypes D543N-A/A, 3'UTR-TGTG+/+, INT4-C/C, and 274C/T-T/T of known polymorphism in the NRAMP1 gene, as well as the genotypes FokI-F/f and FokI-f/f in the VDR gene were most often found in indigenous Warao with active TB. Binomial logistic regression was used for evaluating associations between polymorphisms and risk of contracting TB, an association between NRAMP1-D543N-A/A genotype distribution and TB susceptibility was found in Warao Amerindians. Regarding Venezuelan populations having different genetic backgrounds; statistically significant TB associations concerning NRAMP1-D543N-A/A, INT4-C/C and 3'UTR-TGTG+/+ variant genotype distributions in Warao Amerindians (indigenous) compared to Creole (admixed non-indigenous population) individuals were found. In conclusion, the results thus indicated that the association between NRAMP1-D543N-A/A genotype and TB in Warao Amerindians could support such allele's role in host susceptibility to Mtb infection.


Assuntos
Proteínas de Transporte de Cátions , Tuberculose , Humanos , Regiões 3' não Traduzidas/genética , Venezuela , Predisposição Genética para Doença , Proteínas de Transporte de Cátions/genética , Tuberculose/genética , Genótipo , Estudos de Casos e Controles
10.
Antioxidants (Basel) ; 11(5)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35624839

RESUMO

Non-alcoholic fatty liver disease is characterized by disturbed lipid metabolism and increased oxidative stress. These conditions lead to the activation of different cellular response mechanisms, including senescence. Cellular senescence constitutes an important response to injury in the liver. Recent findings show that chronic oxidative stress can induce senescence, and this might be a driving mechanism for NAFLD progression, aggravating the disturbance of lipid metabolism, organelle dysfunction, pro-inflammatory response and hepatocellular damage. In this context, the modulation of cellular senescence can be beneficial to ameliorate oxidative stress-related damage during NAFLD progression. This review focuses on the role of oxidative stress and senescence in the mechanisms leading to NAFLD and discusses the possibilities to modulate senescence as a therapeutic strategy in the treatment of NAFLD.

11.
Acta Cytol ; 66(5): 359-370, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35717936

RESUMO

BACKGROUND: Cystic lesions of the head and neck are a diagnostic challenge since they are seen in the clinical presentation of a wide variety of conditions. Herein, common and uncommon entities that present as cystic lesions in the head and neck are reviewed. SUMMARY: In this study, peer-reviewed articles were selected using the database PubMed, Google, Google Scholar, and Scopus. Emphasis was placed on peer-reviewed articles that discuss the cytomorphology and differential diagnosis of entities that present as cystic lesions of the head and neck. In the anterior neck, both benign and malignant neoplasms can present, including papillary thyroid carcinoma (PTC), thyroid adenomatoid nodule, parathyroid cysts, and thyroglossal cysts. In the lateral neck, branchial cleft cyst, PTC, ectopic thyroid cyst, and squamous cell carcinomas (human papilloma virus and non- human papilloma virus-related) are common. Age over 40 years raises the possibility of malignancy. In the deep neck, mostly benign cystic entities occur such as a pleomorphic adenoma, paraganglioma, schwannoma, branchial cyst, epidermal inclusion cyst, and lymphoepithelial cyst. Lesions with squamous cell features can pose diagnostic dilemmas. CONCLUSION: Cytologic examination of head and neck cysts can provide valuable information regarding the nature of the cystic lesions. Information about anatomic site and clinical history can assist with the differential diagnoses. Ancillary studies can improve the diagnosis in some cases. Each case should be evaluated very carefully since there are a wide variety of congenital conditions, infectious/inflammatory conditions, benign neoplasms, and primary and secondary malignancies presenting as a cystic mass in the head and neck.


Assuntos
Branquioma , Neoplasias de Cabeça e Pescoço , Neoplasias da Glândula Tireoide , Adulto , Branquioma/diagnóstico , Branquioma/patologia , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Pescoço/patologia , Câncer Papilífero da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia
12.
Mech Ageing Dev ; 201: 111617, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34958827

RESUMO

BACKGROUND: Activated hepatic stellate cells (aHSCs) are the main effector cells during liver fibrogenesis. α-1 adrenergic antagonist doxazosin (DX) was shown to be anti-fibrotic in an in vivo model of liver fibrosis (LF), but the mechanism remains to be elucidated. Recent studies suggest that reversion of LF can be achieved by inducing cellular senescence characterized by irreversible cell-cycle arrest and acquisition of the senescence-associated secretory phenotype (SASP). AIM: To elucidate the mechanism of the anti-fibrotic effect of DX and determine whether it induces senescence. METHODS: Primary culture-activated rat HSCs were used. mRNA and protein expression were measured by qPCR and Western blot, respectively. Cell proliferation was assessed by BrdU incorporation and xCelligence analysis. TGF-ß was used for maximal HSC activation. Norepinephrine (NE), PMA and m-3M3FBS were used to activate alpha-1 adrenergic signaling. RESULTS: Expression of Col1α1 was significantly decreased by DX (10 µmol/L) at mRNA (-30 %) and protein level (-50 %) in TGF-ß treated aHSCs. DX significantly reduced aHSCs proliferation and increased expression of senescence and SASP markers. PMA and m-3M3FBS reversed the effect of DX on senescence markers. CONCLUSION: Doxazosin reverses the fibrogenic phenotype of aHSCs and induces the senescence phenotype.


Assuntos
Senescência Celular , Doxazossina/farmacologia , Células Estreladas do Fígado , Cirrose Hepática , Fenótipo Secretor Associado à Senescência/fisiologia , Transdução de Sinais/efeitos dos fármacos , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/prevenção & controle , Norepinefrina/farmacologia , Ratos , Receptores Adrenérgicos alfa 1/metabolismo , Sulfonamidas/farmacologia
13.
Mech Ageing Dev ; 199: 111572, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34536446

RESUMO

Myofibroblasts play an important role in fibrogenesis. Hepatic stellate cells are the main precursors of myofibroblasts. Cellular senescence is the terminal cell fate in which proliferating cells undergo irreversible cell cycle arrest. Senescent hepatic stellate cells were identified in liver fibrosis. Senescent hepatic stellate cells display decreased collagen production and proliferation. Therefore, induction of senescence could be a protective mechanism against progression of liver fibrosis and the concept of therapy-induced senescence has been proposed to treat liver fibrosis. In this review, characteristics of senescent hepatic stellate cells and the essential signaling pathways involved in senescence are reviewed. Furthermore, the potential impact of senescent hepatic stellate cells on other liver cell types are discussed. Senescent cells are cleared by the immune system. The persistence of senescent cells can remodel the microenvironment and interact with inflammatory cells to induce aging-related dysfunction. Therefore, senolytics, a class of compounds that selectively induce death of senescent cells, were introduced as treatment to remove senescent cells and consequently decrease the disadvantageous effects of persisting senescent cells. The effects of senescent hepatic stellate cells in liver fibrosis need further investigation.


Assuntos
Células Estreladas do Fígado/metabolismo , Cirrose Hepática , Senoterapia/farmacologia , Animais , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia
14.
Infect Genet Evol ; 80: 104171, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31904555

RESUMO

Bovine leukemia virus (BLV) is one of the five agents considered most significant for cattle. It is important to determine the prevalence and molecular epidemiology of BLV throughout the country in order to gain a more thorough understanding of the current situation of BLV and to reveal the possibility of masked genotypes that the primers used by OIE are unable to identify. Blood samples were collected at random from 289 cows distributed in 75 farms across the country. PCR amplification of env, gag and tax gene segments was performed. The obtained amplicons were sequenced and then subjected to phylogenetic analyses. A total of 62% of the cows present at 92% of the farms were BLV-positive for gag fragment. Genotype 1 was exclusively detected by env gene segment when analyzed using previously reported primers. However, tax gene analysis revealed circulation of genotype 6 variants, which were also detected based on env gene analysis with newly designed primers. These results indicate that current genotyping approaches based on partial env sequencing may bias BLV genetic variability approaches and underestimate the diversity of the detected BLV genotypes. This report is one of the first molecular and epidemiological studies of BLV conducted in Colombia, which contributes to the global epidemiology of the virus; it also highlights the substantial impact of BLV on the country's livestock and thus is a useful resource for farmers and government entities.


Assuntos
Leucose Enzoótica Bovina/epidemiologia , Leucose Enzoótica Bovina/virologia , Vírus da Leucemia Bovina/classificação , Vírus da Leucemia Bovina/genética , Animais , Bovinos , Colômbia/epidemiologia , Genes Virais , Variação Genética , Genótipo , Geografia Médica , Epidemiologia Molecular , Filogenia , Filogeografia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Prevalência , Vigilância em Saúde Pública
15.
Cells ; 9(11)2020 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187083

RESUMO

Upon liver injury, hepatic stellate cells (HSCs) transdifferentiate to migratory, proliferative and extracellular matrix-producing myofibroblasts (e.g., activated HSCs; aHSCs) causing liver fibrosis. HSC activation is associated with increased glycolysis and glutaminolysis. Here, we compared the contribution of glycolysis, glutaminolysis and mitochondrial oxidative phosphorylation (OXPHOS) in rat and human HSC activation. Basal levels of glycolysis (extracellular acidification rate ~3-fold higher) and particularly mitochondrial respiration (oxygen consumption rate ~5-fold higher) were significantly increased in rat aHSCs, when compared to quiescent rat HSC. This was accompanied by extensive mitochondrial fusion in rat and human aHSCs, which occurred without increasing mitochondrial DNA content and electron transport chain (ETC) components. Inhibition of glycolysis (by 2-deoxy-D-glucose) and glutaminolysis (by CB-839) did not inhibit rat aHSC proliferation, but did reduce Acta2 (encoding α-SMA) expression slightly. In contrast, inhibiting mitochondrial OXPHOS (by rotenone) significantly suppressed rat aHSC proliferation, as well as Col1a1 and Acta2 expression. Other than that observed for rat aHSCs, human aHSC proliferation and expression of fibrosis markers were significantly suppressed by inhibiting either glycolysis, glutaminolysis or mitochondrial OXPHOS (by metformin). Activation of HSCs is marked by simultaneous induction of glycolysis and mitochondrial metabolism, extending the possibilities to suppress hepatic fibrogenesis by interfering with HSC metabolism.


Assuntos
Glicólise , Células Estreladas do Fígado/patologia , Cirrose Hepática/patologia , Mitocôndrias Hepáticas/metabolismo , Fosforilação Oxidativa , Animais , Glutamina/metabolismo , Humanos , Dinâmica Mitocondrial , Biogênese de Organelas , Fenótipo , Ratos
16.
Biomed Res Int ; 2018: 4706976, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30643808

RESUMO

Regulation of the mechanisms of fibrosis is an important goal in the treatment of liver cirrhosis. One mechanism is the participation of hepatic stellate cells in fibrogenesis when activated by catecholamines. Consequently, α/ß adrenoblockers are proposed as an alternative treatment for chronic liver lesions such as fibrosis and/or cirrhosis and for possible liver regeneration. We herein analyzed the effect of doxazosin and carvedilol treatments during the regeneration of tissue in a hamster model of liver cirrhosis. Tissue samples were examined by H&E and PAS to evaluate tissue damage and with Sirius red to assess collagen fiber content. ALT, AST, albumin, and total proteins were examined by spectrophotometry. Determination of the levels of α-SMA and TGF-ß in hepatic tissue was examined by Western blot and of the expression of TIMP-2, MMP-13, α-FP, HGF, CK-7, and c-Myc was examined by qPCR. Treatment with doxazosin or carvedilol prompted histological recovery and reduced collagen fibers in the livers of cirrhotic hamsters. The expression of TIMP-2 decreased and that of MMP-13 increases in animals treated with adrenoblockers with respect to the group with cirrhosis. Additionally, the concentration of α-SMA and TGF-ß declined with both drugs with respect to placebo p<0.05. On the other hand, each drug treatment led to a distinct scenario for cell proliferation markers. Whereas doxazosin produced no irregularities in α-FP, Ki-67, and c-Myc expression, carvedilol induced an increment in the expression of these markers with respect to the intact. Hence, doxazosin and carvedilol are potential treatments for the regression of hepatic cirrhosis in hamsters in relation to the decrease of collagen in the hepatic parenchyma. However, at regeneration level we observed that doxazosin caused slight morphological changes in hepatocytes, such as its balonization without affecting the hepatic function, and on the other hand, carvedilol elicited a slight irregular expression of cell proliferation markers.


Assuntos
Antígenos de Diferenciação/biossíntese , Carvedilol/farmacologia , Proliferação de Células/efeitos dos fármacos , Doxazossina/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Cirrose Hepática , Regeneração Hepática/efeitos dos fármacos , Animais , Cricetinae , Modelos Animais de Doenças , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Masculino , Mesocricetus
17.
Pediatr. aten. prim ; 24(94)abr. - jun. 2022. ilus, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-212133

RESUMO

Aunque la causa más frecuente de los procesos diarreicos infantiles son las infecciones, ante cuadros graves y prolongados en el tiempo en los lactantes hay que descartar causas congénitas como trastornos genéticos o inmunodeficiencias. La colitis por citomegalovirus (CMV) es una causa poco frecuente de diarrea crónica en niños inmunocompetentes. Por lo general, su curso es leve y autolimitado, por lo que debemos pensar la posibilidad de que exista una inmunodeficiencia en los casos con una evolución más grave. Se recomienda realizar un estudio endoscópico en estos pacientes, precisando tratamiento antiviral aquellos con un curso de la enfermedad más grave o en caso de confirmarse situación de inmunodepresión (AU)


Although the most frequent cause of childhood diarrheal processes is infection, in the case of severe and prolonged symptoms in infants, congenital causes such as genetic disorders or immunodeficiencies must be ruled out. Cytomegalovirus (CMV) colitis is a rare cause of chronic diarrhoea in immunocompetent children. In general, it is a mild and self-limiting disease, so the possibility of immunodeficiency should be considered in cases with a more severe course. Performance of an endoscopic examination is recommended in these patients, and antiviral treatment is required in those with more severe forms of disease or with confirmed immunosuppression. (AU)


Assuntos
Humanos , Feminino , Lactente , Diarreia Infantil/diagnóstico , Diarreia Infantil/etiologia , Índice de Gravidade de Doença , Doença Crônica
18.
Pediatr. aten. prim ; 23(92): 425-428, oct.- dic. 2021. ilus, tab
Artigo em Espanhol | IBECS (Espanha) | ID: ibc-222905

RESUMO

El quiste del colédoco es una dilatación congénita de la vía biliar. La presentación clínica es inespecífica y a menudo supone un dilema diagnóstico. Se debe tener un elevado índice de sospecha ante casos de ictericia, dolor abdominal y masa abdominal palpable. Para su diagnóstico es fundamental un estudio de imagen, siendo el indicado de forma inicial la ecografía. Pueden presentar múltiples complicaciones, incluyendo colangitis, pancreatitis, colangiocarcinoma, cirrosis biliar y hepática. Para su manejo se recomienda la resección del quiste, para evitar complicaciones y disminuir el riesgo de malignización. Se recomienda un seguimiento a largo plazo, con ecografías y análisis anuales, dado que el riesgo de malignización se mantiene elevado incluso tras la escisión del quiste. El abordaje óptimo de esta patología requiere un enfoque multidisciplinar, desde la sospecha diagnóstica que a menudo procederá de los servicios de Atención Primaria, incluyendo también gastroenterólogos, cirujanos, patólogos y radiólogos (AU)


Bile duct cyst is a congenital dilation of the bile duct. Clinical presentation is non-specific and often poses a diagnostic dilemma. It should be highly suspected in cases of jaundice, abdominal pain and a palpable abdominal mass. An imaging study is essential for diagnosis, an ultrasound being the most suitable initially. It can present multiple complications, including cholangitis, pancreatitis, cholangiocarcinoma, biliary and hepatic cirrhosis. For its management, resection of the cyst is recommended to avoid complications and reduce the risk of malignancy. Long-term follow-up with annual ultrasound scans and tests is recommended, as the risk of malignancy remains high even after excision of the cyst. The optimal approach to this pathology requires a multidisciplinary perspective, starting from the diagnostic suspicion that will often come from Primary Care services, and including also gastroenterologists, surgeons, pathologists and radiologists (AU)


Assuntos
Humanos , Masculino , Lactente , Colestase/etiologia , Icterícia/etiologia , Cisto do Colédoco/complicações , Cisto do Colédoco/diagnóstico , Cisto do Colédoco/cirurgia
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