Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Stem Cells Int ; 2024: 2385568, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015674

RESUMO

Patients with focal segmental glomerulosclerosis (FSGS) who are refractory to drug treatment may present progressive loss of kidney function, leading to chronic kidney disease stage 5 under dialysis treatment. The safety of systemic administration of bone marrow-derived mononuclear cells (BMDMCs) has been shown in different preclinical models of kidney diseases. However, to date, no study has evaluated the safety and biodistribution of BMDMCs after infusion in renal arteries in patients with FSGS. We used a prospective, non-randomized, single-center longitudinal design to investigate this approach. Five patients with refractory FSGS and an estimated glomerular filtration rate (eGFR) between 20 and 40 ml/min/1.73 m2 underwent bone marrow aspiration and received an arterial infusion of autologous BMDMCs (5 × 107) for each kidney. In addition, BMDMCs labeled with technetium-99m (99mTc-BMDMCs) were used to assess the biodistribution by scintigraphy. All patients completed the 270-day follow-up protocol with no serious adverse events. A transient increase in creatinine was observed after the cell therapy, with improvement on day 30. 99mTc-BMDMCs were detected in both kidneys and counts were higher after 2 hr compared with 24 hr. The arterial infusion of BMDMCs in both kidneys of patients with FSGS was considered safe with stable eGFR at the end of follow-up. This trial is registered with NCT02693366.

2.
bioRxiv ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712079

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related deaths, and commonly associated with hepatic fibrosis or cirrhosis. This study aims to establish a rat model mimicking the progression from liver fibrosis to cirrhosis and subsequently to HCC using thioacetamide (TAA). We utilized male Lewis rats, treating them with intra-peritoneal injections of TAA. These rats received bi-weekly injections of either 200 mg/kg TAA or saline (as a control) over a period of 34 weeks. The development of cirrhosis and hepatocarcinogenesis was monitored through histopathological examinations, biochemical markers, and immunohistochemical analyses. Our results demonstrated that chronic TAA administration induced cirrhosis and well-differentiated HCC, characterized by increased fibrosis, altered liver architecture, and enhanced hepatocyte proliferation. Biochemical analyses revealed significant alterations in liver function markers, including elevated alpha-fetoprotein (AFP) levels, without affecting kidney function or causing significant weight loss or mortality in rats. This TAA-induced cirrhosis and HCC rat model successfully replicates the clinical progression of human HCC, including liver function impairment and early-stage liver cancer characteristics. It presents a valuable tool for future research on the mechanisms of antitumor drugs in tumor initiation and development.

3.
Int J Mol Sci ; 24(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37686209

RESUMO

Metabolic-dysfunction-associated steatotic liver disease (MASLD), which affects 30 million people in the US and is anticipated to reach over 100 million by 2030, places a significant financial strain on the healthcare system. There is presently no FDA-approved treatment for MASLD despite its public health significance and financial burden. Understanding the connection between point mutations, liver enzymes, and MASLD is important for comprehending drug toxicity in healthy or diseased individuals. Multiple genetic variations have been linked to MASLD susceptibility through genome-wide association studies (GWAS), either increasing MASLD risk or protecting against it, such as PNPLA3 rs738409, MBOAT7 rs641738, GCKR rs780094, HSD17B13 rs72613567, and MTARC1 rs2642438. As the impact of genetic variants on the levels of drug-metabolizing cytochrome P450 (CYP) enzymes in human hepatocytes has not been thoroughly investigated, this study aims to describe the analysis of metabolic functions for selected phase I and phase II liver enzymes in human hepatocytes. For this purpose, fresh isolated primary hepatocytes were obtained from healthy liver donors (n = 126), and liquid chromatography-mass spectrometry (LC-MS) was performed. For the cohorts, participants were classified into minor homozygotes and nonminor homozygotes (major homozygotes + heterozygotes) for five gene polymorphisms. For phase I liver enzymes, we found a significant difference in the activity of CYP1A2 in human hepatocytes carrying MBOAT7 (p = 0.011) and of CYP2C8 in human hepatocytes carrying PNPLA3 (p = 0.004). It was also observed that the activity of CYP2C9 was significantly lower in human hepatocytes carrying HSD17B13 (p = 0.001) minor homozygous compared to nonminor homozygous. No significant difference in activity of CYP2E1, CYP2C8, CYP2D6, CYP2E1, CYP3A4, ECOD, FMO, MAO, AO, and CES2 and in any of the phase II liver enzymes between human hepatocytes carrying genetic variants for PNPLA3 rs738409, MBOAT7 rs641738, GCKR rs780094, HSD17B13 rs72613567, and MTARC1 rs2642438 were observed. These findings offer a preliminary assessment of the influence of genetic variations on drug-metabolizing cytochrome P450 (CYP) enzymes in healthy human hepatocytes, which may be useful for future drug discovery investigations.


Assuntos
Doenças do Sistema Digestório , Fígado Gorduroso , Hepatopatias , Humanos , Citocromo P-450 CYP2C8/genética , Citocromo P-450 CYP2E1 , Estudo de Associação Genômica Ampla , Hepatócitos
4.
Organogenesis ; 19(1): 2247576, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-37598346

RESUMO

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), the most common types of cholestatic liver disease (CLD), result in enterohepatic obstruction, bile acid accumulation, and hepatotoxicity. The mechanisms by which hepatocytes respond to and cope with CLD remain largely unexplored. This study includes the characterization of hepatocytes isolated from explanted livers of patients with PBC and PSC. We examined the expression of hepatocyte-specific genes, intracellular bile acid (BA) levels, and oxidative stress in primary-human-hepatocytes (PHHs) isolated from explanted livers of patients with PBC and PSC and compared them with control normal human hepatocytes. Our findings provide valuable initial insights into the hepatocellular response to cholestasis in CLD and help support the use of PHHs as an experimental tool for these diseases.


Assuntos
Carcinoma Hepatocelular , Colestase , Neoplasias Hepáticas , Humanos , Ácidos e Sais Biliares
5.
Semin Liver Dis ; 42(4): 413-422, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36044927

RESUMO

Although the underlying cause may vary across countries and demographic groups, liver disease is a major cause of morbidity and mortality globally. Orthotopic liver transplantation is the only definitive treatment for liver failure but is limited by the lack of donor livers. The development of drugs that prevent the progression of liver disease and the generation of alternative liver constructs for transplantation could help alleviate the burden of liver disease. Bioengineered livers containing human induced pluripotent stem cell (iPSC)-derived liver cells are being utilized to study liver disease and to identify and test potential therapeutics. Moreover, bioengineered livers containing pig hepatocytes and endothelial cells have been shown to function and survive after transplantation into pig models of liver failure, providing preclinical evidence toward future clinical applications. Finally, bioengineered livers containing human iPSC-derived liver cells have been shown to function and survive after transplantation in rodents but require considerable optimization and testing prior to clinical use. In conclusion, bioengineered livers have emerged as a suitable tool for modeling liver diseases and as a promising alternative graft for clinical transplantation. The integration of novel technologies and techniques for the assembly and analysis of bioengineered livers will undoubtedly expand future applications in basic research and clinical transplantation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Hepatopatias , Falência Hepática , Humanos , Suínos , Animais , Células Endoteliais , Hepatócitos , Fígado/fisiologia , Hepatopatias/cirurgia
6.
Life Sci ; 301: 120615, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35526595

RESUMO

The liver, a component of the gastrointestinal tract, is one of the most important organs in the human body. The liver performs over 500 functions to promote physiological homeostasis. In addition, the liver acts as a screen, by metabolizing substances carried by blood coming from the digestive tract before they enter the systemic circulation. This vital function exposes the hepatic tissue to hepatotoxic agents, which can lead to liver damage if the organ's repair and regenerative capacity is insufficient. Several conditions such as persistent exposure to hepatitis C and B viruses, alcohol, and drugs can provoke this disbalance, eventually leading to liver cirrhosis, which is an irreversible and life-threatening condition. This paradigm of irreversibility began to be reconsidered when several studies showed that hepatic fibrosis is potentially reversible after cessation of exposure to the hepatotoxic agent or eradication of the primary disease. In the context of basic research in liver fibrosis and cirrhosis, it is essential to keep in mind that the capacity of the organ to recover spontaneously might be a significant limitation to long-term studies that use experimental models of liver cirrhosis. Here, we review animal models where liver cirrhosis is experimentally induced. We focus on a surgery-based model, i.e., bile duct ligation (BDL), and hepatotoxic drugs such as carbon tetrachloride (CCl4), thioacetamide (TAA), and dimethylnitrosamine (DMN) administrated alone or in association with alcohol, the latter to potentialize the hepatotoxic effect of these agents. Also, we analyze the effects of these approaches, emphasizing the risks, spontaneous reversibility, and outcomes on animal health.


Assuntos
Cirrose Hepática Experimental , Roedores , Animais , Tetracloreto de Carbono/toxicidade , Modelos Animais de Doenças , Fígado/patologia , Cirrose Hepática/patologia , Cirrose Hepática Experimental/induzido quimicamente , Modelos Teóricos , Tioacetamida/toxicidade
7.
Hepatol Commun ; 6(7): 1561-1573, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35289126

RESUMO

The initial creation of human-induced pluripotent stem cells (iPSCs) set the foundation for the future of regenerative medicine. Human iPSCs can be differentiated into a variety of cell types in order to study normal and pathological molecular mechanisms. Currently, there are well-defined protocols for the differentiation, characterization, and establishment of functionality in human iPSC-derived hepatocytes (iHep) and iPSC-derived cholangiocytes (iCho). Electrophysiological study on chloride ion efflux channel activity in iHep and iCho cells has not been previously reported. We generated iHep and iCho cells and characterized them based on hepatocyte-specific and cholangiocyte-specific markers. The relevant transmembrane channels were selected: cystic fibrosis transmembrane conductance regulator, leucine rich repeat-containing 8 subunit A, and transmembrane member 16 subunit A. To measure the activity in these channels, we used whole-cell patch-clamp techniques with a standard intracellular and extracellular solution. Our iHep and iCho cells demonstrated definitive activity in the selected transmembrane channels, and this approach may become an important tool for investigating human liver biology of cholestatic diseases.


Assuntos
Células-Tronco Pluripotentes Induzidas , Diferenciação Celular/fisiologia , Células Epiteliais , Hepatócitos , Humanos , Fígado
8.
Organogenesis ; 16(3): 95-112, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32799604

RESUMO

Acellular liver scaffolds (ALS) have arisen as potential candidates for transplantation. Until now, all reports involving ALS transplantation failed in surgical method descriptions and do not offer support to scientists to reproduce the procedures used in experimental microsurgery to make the results comparable to literature. To overcome the lack of detail information, we described surgical steps details to perform heterotopic and partial orthotopic surgical models to promote ALS transplantation. After preservation and vessel cannulation steps, the liver grafts were decellularized. In addition, ex vivo blood perfusion tests were performed to obtain a successful anticoagulation treatment prior in vivo transplantation. Then, methods of partial liver resection, combination of hand-suture and cuff techniques to complete end-to-end anastomosis between the scaffold and the recipient animal were performed. These procedures which take 30-60 min and were efficient to allow acellular liver scaffold viability and recellularization of different types of cell post-surgery. In conclusion, our methods are practical and simple promising approach that provides the opportunity to investigate ways to achieve sufficient liver function post-transplantation in vivo.


Assuntos
Transplante de Fígado/métodos , Fígado/cirurgia , Microcirurgia/métodos , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Matriz Extracelular , Feminino , Masculino , Modelos Anatômicos , Ratos , Ratos Wistar , Transplante Heterotópico
9.
Crit Care Med ; 42(7): e510-24, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24633189

RESUMO

OBJECTIVE: The advantage of using autologous bone marrow-derived mononuclear cells to treat acute respiratory distress syndrome patients is to prevent immunological rejection. However, bone marrow-derived mononuclear cells may be altered by different acute respiratory distress syndrome etiologies, resulting in questionable efficacy and thus limited clinical application. We aimed to investigate the effects of bone marrow-derived mononuclear cells obtained from healthy and acute respiratory distress syndrome donors on pulmonary and extrapulmonary acute respiratory distress syndrome. DESIGN: Prospective, randomized, controlled experimental study. SETTING: University research laboratory. SUBJECTS: Two hundred and twenty-five C57BL/6 mice. INTERVENTIONS: Acute respiratory distress syndrome was induced by Escherichia coli lipopolysaccharide intratracheally (ARDSp) or intraperitoneally (ARDSexp). Control mice (Healthy) received saline solution intratracheally (Cp) or intraperitoneally (Cexp). After 24 hours, whole bone marrow cells were analyzed in vitro: 1) colony-forming unit-fibroblasts and 2) hematopoietic stem cells, neutrophils, T helper lymphocytes, B lymphocytes, and nonhematopoietic precursors. After cell characterization, all groups received saline or bone marrow-derived mononuclear cells (2 × 10), obtained from Cp, Cexp, ARDSp, and ARDSexp donor mice, IV, on day 1. MEASUREMENTS AND MAIN RESULTS: On day 1, in ARDSp, different patterns of colony formation were found, with nonstromal cells (mainly neutrophils) predominating over fibroblastoid colonies. In ARDSexp, irregular colony-forming unit-fibroblasts morphology with dispersed proliferating colonies and a greater number of hematopoietic stem cells were observed. In ARDSp, colony-forming unit-fibroblasts count was higher but not measurable in ARDSexp. In ARDSp, monocytes and T lymphocytes were increased and hematopoietic precursor cells reduced, with no significant changes in ARDSexp. On day 7, bone marrow-derived mononuclear cells improved survival and attenuated changes in lung mechanics, alveolar collapse, inflammation, pulmonary fibrosis, and apoptosis in the lung and distal organs, regardless of donor type. CONCLUSIONS: Bone marrow-derived mononuclear cells from ARDSp and ARDSexp donors showed different characteristics but were as effective as cells obtained from healthy donors in reducing inflammation and remodeling, suggesting the utility of autologous transplant of bone marrow-derived mononuclear cells in the clinical setting.


Assuntos
Células da Medula Óssea/citologia , Síndrome do Desconforto Respiratório/terapia , Transplante de Células-Tronco/métodos , Animais , Feminino , Fibroblastos , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/citologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Mecânica Respiratória
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA