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1.
Transpl Int ; 31(12): 1357-1368, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29974521

RESUMO

A double-blind randomized controlled trial was performed to compare the safety and efficacy of α-lipoic acid (ALA) in liver transplantation (LT). The grafts were randomized to receive ALA or placebo before the cold ischemia time. Furthermore, patients transplanted with the ALA-perfused graft received 600 mg of intravenous ALA, while patients with the nonperfused graft received the placebo just before graft reperfusion. Hepatic biopsy was performed 2 h postreperfusion. Blood samples were collected before, during and 1 and 2 days after reperfusion. Quantitative polymerase chain reaction (qPCR) analysis was performed on biopsies to assess genes involved in the response to hypoxia, apoptosis, cell growth, survival and proliferation, cytokine production and tissue damage protection. Nine of 40 patients developed postreperfusion syndrome (PRS), but seven of them belonged to the control group. There was a decrease in PHD2 and an increase in alpha subunit of hypoxia-inducible factor-1 (HIF-1α) and baculoviral IAP repeat containing 2 (Birc2) transcript levels in the biopsies from the ALA-treated versus the control group of patients. Additionally, plasma levels of alarmins were lower in ALA-treated patients than control patients, which suggests that ALA-treated grafts are less inflammatory than untreated grafts. These results showed that ALA is safe for use in LT, induces gene changes that protect against hypoxia and oxidative stress and reduces the appearance of PRS.


Assuntos
Transplante de Fígado , Traumatismo por Reperfusão/prevenção & controle , Ácido Tióctico/farmacologia , Idoso , Alarminas/metabolismo , Apoptose , Biópsia , Isquemia Fria , Citocinas/metabolismo , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Hipóxia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Inibidoras de Apoptose/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Segurança do Paciente , Projetos Piloto , Reperfusão/métodos , Ubiquitina-Proteína Ligases/metabolismo
2.
Int J Mol Sci ; 19(1)2018 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-29300330

RESUMO

Organ replacement is an option to mitigate irreversible organ damage. This procedure has achieved a considerable degree of acceptance. However, several factors significantly limit its effectiveness. Among them, the initial inflammatory graft reaction due to ischemia-reperfusion injury (IRI) has a fundamental influence on the short and long term organ function. The reactive oxygen species (ROS) produced during the IRI actively participates in these adverse events. Therapeutic strategies that tend to limit the action of free radicals could result in beneficial effects in transplantation outcome. Accordingly, the anti-oxidant α-lipoic acid (ALA) have been proved to be protective in several animal experimental models and humans. In a clinical trial, ALA was found to decrease hepatic IRI after hepatic occlusion and resection. Furthermore, the treatment of cadaveric donor and recipient with ALA had a protective effect in the short-term outcome in simultaneous kidney and pancreas transplanted patients. These studies support ALA as a drug to mitigate the damage caused by IRI and reinforce the knowledge about the deleterious consequences of ROS on graft injury in transplantation. The goal of this review is to overview the current knowledge about ROS in transplantation and the use of ALA to mitigate it.


Assuntos
Radicais Livres/metabolismo , Ácido Tióctico/farmacologia , Transplante , Animais , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/terapia
3.
Biomed Res Int ; 2022: 9018074, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35872850

RESUMO

The excessive demand for organ transplants has promoted the development of strategies that increase the supply of immune compatible organs, such as xenotransplantation of genetically modified pig organs and the generation of bioartificial organs. We describe a method for the partial replacement of rat endothelial cells for human endothelial cells in a rat's kidney, obtaining as a final result a rat-human bioartificial kidney. First, in order to maintain parenchymal epithelial cells and selectively eliminate rat endothelial cells, three methods were evaluated in which different solutions were perfused through the renal artery: 0.1% sodium dodecyl sulfate (SDS), 0.01% SDS, and hyperosmolar solutions of sucrose. Then, partially decellularized kidneys were recellularized with human endothelial cells and finally transplanted in an anesthetized rat. The solution of 0.1% SDS achieved the highest vascular decellularization but with high degree of damage in the parenchyma side. On the contrary, 0.01% SDS and hyperosmolar solutions achieved a partial degree of endothelial decellularization. TUNEL assays reveal that hyperosmolar solutions maintained a better epithelial cell viability contrasting with 0.01% SDS. Partially decellularized kidneys were then recellularized with human endothelial cells. Histological analysis showed endothelial cells attached in almost all the vascular bed. Recellularized kidney was transplanted in an anesthetized rat. After surgery, recellularized kidney achieved complete perfusion, and urine was produced for at least 90 min posttransplant. Histological analysis showed endothelial cells attached in almost all the vascular bed. Therefore, endothelial decellularization of grafts and recellularization with human endothelial cells derived from transplant recipients can be a feasible method with the aim to reduce the damage of the grafts.


Assuntos
Células Endoteliais , Alicerces Teciduais , Animais , Matriz Extracelular , Humanos , Rim , Perfusão , Ratos , Suínos , Engenharia Tecidual/métodos
4.
J Clin Neurosci ; 74: 65-68, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32001112

RESUMO

We analyze the differential brain volume changes in highly active multiple sclerosis (HAMS) vs. non-HAMS patients during the disease onset. METHODS: HAMS was defined as: a) patients with 1 relapse in the previous year and at least 1 T1 gadolinium-enhancing lesion or 9 or more T2 lesions while on therapy with other disease modifying treatment (DMD); or b) patients with 2 or more relapses in the previous year, whether on DMD or not. High-resolution T1 weighted MRI scans were acquired at onset and every 12 months for 2 years. Lesion load and brain volume measurements were determined. At onset, gray matter volume (GMV) and white matter volume (WMV) tissue volumes were calculated using the SIENAX. Longitudinal changes were estimated by using SIENA to calculate the percentage of brain volume loss. Differences between volumes per group at onset and at the end of the follow up were established. RESULTS: 64 patients, mean age 38.4 years, 35 (57%) women were included. A total of 14 (21%) were classified as HAMS. At onset, HAMS patients showed lower GMV and WMV volume compared with non-HAMS patients (p = 0.003 and p = 0.01, respectively). During the follow up, HAMS patients showed a higher decrease in GM volume compared with non-HAMS patients (-0.61 vs. - 0.77, p < 0.001) independent from new lesion as well as relapse rate activity during follow up. CONCLUSION: HAMS increased rates of GMV atrophy over 24 months compared to non-HAMS patients independent from relapse rate and new T2 lesions.


Assuntos
Substância Cinzenta/patologia , Esclerose Múltipla/patologia , Substância Branca/patologia , Adulto , Atrofia/patologia , Encéfalo/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Recidiva
5.
Biomark Med ; 13(11): 895-906, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31379196

RESUMO

Aim: It is important to find biomarkers that identify the graft quality in kidney transplantation. Results & methodology: The level of SLPI in the cold preservation solution was used as a marker to predict early kidney graft function after transplantation. Before transplantation, kidneys were washed and SLPI was measured in the discarded solution. A retrospective analysis showed that patients with delayed graft function or rejection episodes in post-trasplant, had higher SLPI concentrations in the perfusion solution than patients without delayed graft function or rejections. Furthermore, SLPI could discriminate between patients with better or worse estimated glomerular filtration rate among low-risk patients (kidney donor profile index <80). Discussion & conclusion: These results suggest that the SLPI concentration in the perfusion solutions could be a predictor of short-term organ function and a complement to the kidney donor profile index score.


Assuntos
Rim/química , Perfusão/instrumentação , Inibidor Secretado de Peptidases Leucocitárias/análise , Idoso , Biomarcadores/análise , Função Retardada do Enxerto , Feminino , Taxa de Filtração Glomerular , Humanos , Rim/metabolismo , Rim/fisiopatologia , Rim/cirurgia , Transplante de Rim , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Inibidor Secretado de Peptidases Leucocitárias/metabolismo
6.
Sci Rep ; 8(1): 5332, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29593284

RESUMO

Secretory Leukocyte Proteinase Inhibitor (SLPI) is an antiinflammatory peptide that blocks the activity of serine proteases, primarily the neutrophil elastase. In an attempt to direct the activity of SLPI on inflamed sites, a chimera consisting of the transglutaminase II substrate domain of trappin 2 (cementoin), and the mature SLPI protein was constructed. Cell attachment and biological activity were compared between SLPI and this chimera. By using whole cell ELISA, fluorescence microscopy and flow cytometry assays we observed that the cementoin-SLPI fusion protein (FP) but not SLPI attached to a human lung epithelial cell line and monocytes. A maximum attachment was achieved 15 min after FP was added to the cell cultures. In an elastase activity assay, we observed that FP retained its antiprotease activity and that at equimolar amount of proteins, FP was more efficient than SLPI in the inhibition. Both, FP and SLPI inhibits IL-2-induced lymphocyte proliferation, however, lower amounts of FP were required to achieve this inhibition. Furthermore, FP binds to mycobacteria and maintained the bactericidal activity observed for SLPI. Overall, these results show that this new chimera is able to attach to the cell surfaces retaining and improving some biological activities described for SLPI.


Assuntos
Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Monócitos/metabolismo , Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Inibidor Secretado de Peptidases Leucocitárias/metabolismo , Biomarcadores , Linhagem Celular , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Imunofluorescência , Humanos , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Monócitos/efeitos dos fármacos , Peptídeos/genética , Ligação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Inibidor Secretado de Peptidases Leucocitárias/genética , Inibidor Secretado de Peptidases Leucocitárias/farmacologia
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