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1.
Plast Reconstr Surg ; 151(2): 307-313, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36696312

RESUMO

BACKGROUND: Striae distensae evaluation criteria have been recently described, but none is focused on objective striae assessment. With the purpose of better and objectively estimating the severity of striae distensae, the Objective Stretch Marks Assessment Scale has been developed by the authors' team. METHODS: Seven hundred White patients were included in the study and assessed. To assess the severity of striae distensae, abdomen, breasts, hips, gluteal area, back area, thighs, calves, and upper limbs photonumeric grading scales were developed. The Rasch model was used as part of the validation process. A score was attributed to each patient, based on the scales we developed. The interrater reliability and test-retest reliability were analyzed. RESULTS: Eight photonumeric scales for striae distensae treatment outcomes assessment were developed. All scales exceeded criteria for acceptability, reliability and validity. The interrater and intrarater reliabilities were good, with a substantial or virtually perfect interrater reliability for the total score (P = 0.16). CONCLUSIONS: The authors' results allowed them to validate the Objective Stretch Marks Assessment Scale as a reliable and reproducible tool to assess striae distensae treatment outcomes. This scale could be also considered as an important new metric that can be used in clinical research.


Assuntos
Estrias de Distensão , Humanos , Estrias de Distensão/diagnóstico , Estrias de Distensão/terapia , Reprodutibilidade dos Testes , Mama , Resultado do Tratamento , Abdome
2.
Aesthetic Plast Surg ; 45(3): 1282-1293, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33474574

RESUMO

INTRODUCTION: Striae distensae (SD) appear clinically as parallel striae, lying perpendicular to the tension lines of the skin. SD evolve into two clinical phases, an initial inflammatory phase in which they are called "striae rubrae" (SR) and a chronic phase in which they are called striae albae (SA). Fibroblasts seem to play a key role in the pathogenesis of stretch marks. This study was aimed at describing and analyzing stretch marks-derived fibroblasts (SMF), the differences between SR- and SA-derived fibroblasts (SRF, SAF), testing two treatments in vitro (sodium ascorbate and PrP) on SAF. MATERIAL AND METHODS: To characterize the SMF, the expression of alpha smooth muscle actin (alpha SMA) was investigated. Type I collagen expression was measured in SAF, before and after adding different PrP concentrations and sodium ascorbate in the culture medium. Results were processed through statistical analysis models using the Student's t-test. RESULTS: A significant increase in alpha SMA (P <0.001) was observed in SRF. SAF treated with PrP and sodium ascorbate showed a resumption of their metabolic activity by an increase in collagen type I production and cell proliferation. After 24 h of incubation with PrP 1% and PrP 5% + sodium ascorbate, cell viability was increased by 140% and 151% and by 156 and 178% after 48 h, respectively, compared to the control. CONCLUSION: Our study shows that a biologically mediated improvement in SMF metabolic activity is possible. Our promising results require further trials to be able to confirm the reproducibility of this combined treatment, particularly in vivo. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable.


Assuntos
Plasma Rico em Plaquetas , Estrias de Distensão , Ácido Ascórbico/farmacologia , Fibroblastos , Humanos , Reprodutibilidade dos Testes , Estrias de Distensão/tratamento farmacológico
4.
JHEP Rep ; 2(4): 100119, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32695967

RESUMO

BACKGROUND & AIMS: Hypothermic oxygenated machine perfusion (HOPE) is a promising technique for providing oxygen to the liver during graft preservation; however, because of associated logistical constraints, addition of an oxygen transporter to static cold-storage solutions (SCS) might be easier. M101 is marine worm haemoglobin that has been shown to improve kidney preservation in the clinic when added to SCS. This study evaluated the effects of the addition of M101 to SCS on the quality of pig liver graft preservation. METHODS: Pig liver grafts were preserved using SCS, HOPE, or SCS+M101, and the liver functions were compared during cold preservation and after orthotopic allotransplantation (OLT) in pigs. RESULTS: During preservation of the liver grafts, mitochondrial function, ATP synthesis, antioxidant capacities, and hepatocyte architecture were better preserved, and free radical production, antioxidant activities, and inflammatory mediators were lower, with HOPE or SCS+M101 than with SCS alone. However, after 1 h of preservation, liver functions with HOPE were superior to those with SCS+M101. After 6 h of preservation and OLT, blood levels of aspartate and alanine aminotransferases and lactate dehydrogenase increased with a peak effect at Day 1 post-transplant; values were similar with HOPE and SCS+M101, and were significantly lower than those in the SCS group. At Days 1 and 3, tumor necrosis factor α levels remained lower with HOPE and SCS+M101 vs. SCS. At Day 7, liver cell necrosis and inflammation were less marked in both oxygenated groups. CONCLUSIONS: When added to SCS, M101 effectively oxygenates liver grafts during preservation, preventing post-transplant injury; although graft performances are below those achieved with HOPE. LAY SUMMARY: When transported between donors and recipients, even cold-stored liver grafts need oxygen to maintain their viability. To provide them with oxygen, we added a marine worm super haemoglobin (M101) to the cold-storage solution UWCS. Using a pig liver transplant model, we revealed that livers cold stored with UWCS+M101 showed improved oxygenation compared with simple cold-storage solutions, but did not reach the oxygenation level achieved with machine perfusion.

5.
Artigo em Inglês | MEDLINE | ID: mdl-29733120

RESUMO

Ischaemia reperfusion (I/R) is associated with liver injury and impaired regeneration during partial hepatectomy (PH). The aim of this study was to investigate the effect of thymoquinone (TQ), the active compound of essential oil obtained from Nigella sativa seeds, on rat liver after PH. Male Wistar rats were divided equally into four groups (n = 6) receiving an oral administration of either vehicle solution (sham and PH groups) or TQ at 30 mg/kg (TQ and TQ + PH groups) for 10 consecutive days. Then, rats underwent PH (70%) with 60 minutes of ischaemia followed by 24 hours of reperfusion (PH and TQ + PH groups). Alanine aminotransferase (ALT) activity and histopathological damage were determined. Also, antioxidant parameters, liver regeneration index, hepatic adenosine triphosphate (ATP) content, endoplasmic reticulum (ER) stress and apoptosis were assessed. In response to PH under I/R, liver damage was significantly alleviated by TQ treatment as evidenced by the decrease in ALT activity (P < .01) and histological findings (P < .001). In parallel, TQ preconditioning increased hepatic antioxidant capacities. Moreover, TQ improved mitochondrial function (ATP, P < .05), attenuated ER stress parameters and repressed the expression of apoptotic effectors. Taken together, our results suggest that TQ preconditioning could be an effective strategy to reduce liver injury after PH under I/R. The protective effects were mediated by the increase of antioxidant capacities and the decrease of ER stress and apoptosis.

6.
Biomed Pharmacother ; 94: 964-973, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28810534

RESUMO

This study was undertaken to evaluate the protective effect of thymoquinone (TQ), the bioactive compound of Nigella sativa seeds, against warm ischemia-reperfusion (I/R) injury in liver. Rats were given an oral administration of a vehicle solution (sham group) or TQ at the appropriate dose (10, 20, 30 and 40mg/kg) for ten days consecutively. Following, they were subjected to 60min of partial hepatic ischemia followed by 24h of reperfusion. .Transaminase activities, histopathological changes, TNFα and antioxidant parameters were evaluated. Also, endoplasmic reticulum (ER) stress, mitochondrial damage and apoptosis were studied. In addition, ERK and P38 phosphorylation was determined by Western blot technique. We found that TQ at 30mg/kg is the effective dose to protect rat liver against I/R injury. Moreover, 30mg/kg of TQ prevented histological damages, inflammation and oxidative stress. Interestingly, it decreased the expression of ER stress parameters including GRP78, CHOP and caspase-12. In parallel, it improved mitochondrial function and attenuated the expression of apoptotic parameters. Furthermore, TQ significantly enhanced ERK and P38 phosphorylation. In conclusion, we demonstrated the potential of TQ to protect the rat liver against I/R injury through the prevention of ER stress and mitochondrial dysfunction. These effects implicate the prevention of oxidative stress.


Assuntos
Apoptose/efeitos dos fármacos , Benzoquinonas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Isquemia/tratamento farmacológico , Fígado/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Antioxidantes/metabolismo , Isquemia/metabolismo , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Reperfusão/métodos , Traumatismo por Reperfusão/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Isquemia Quente/métodos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
7.
Transplantation ; 101(7): e205-e213, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28403128

RESUMO

BACKGROUND: Control of warm ischemia (WI) lesions that occur with donation after circulatory death (DCD) would significantly increase the donor pool for liver transplantation. We aimed to determine whether a novel, oxygenated and hypothermic machine perfusion device (HMP Airdrive system) improves the quality of livers derived from DCDs using a large animal model. METHODS: Cardiac arrest was induced in female large white pigs by intravenous injection of potassium chloride. After 60 minutes of WI, livers were flushed in situ with histidine-tryptophan-ketoglutarate and subsequently preserved either by simple cold storage (WI-SCS group) or HMP (WI-HMP group) using Belzer-MPS solution. Liver grafts procured from heart-beating donors and preserved by SCS served as controls. After 4 hours of preservation, all livers were transplanted. RESULTS: All recipients in WI-SCS group died within 6 hours after transplantation. In contrast, the HMP device fully protected the liver against lethal ischemia/reperfusion injury, allowing 100% survival rate. A postreperfusion syndrome was observed in all animals of the WI-SCS group but none of the control or WI-HMP groups. After reperfusion, HMP-preserved livers functioned better and showed less hepatocellular and endothelial cell injury, in agreement with better-preserved liver histology relative to WI-SCS group. In addition to improved energy metabolism, this protective effect was associated with an attenuation of inflammatory response, oxidative load, endoplasmic reticulum stress, mitochondrial damage, and apoptosis. CONCLUSIONS: This study demonstrates for the first time the efficacy of the HMP Airdrive system to protect liver grafts from lethal ischemic damage before transplantation in a clinically relevant DCD model.


Assuntos
Hepatectomia , Transplante de Fígado/instrumentação , Fígado/cirurgia , Perfusão/instrumentação , Traumatismo por Reperfusão/prevenção & controle , Isquemia Quente/instrumentação , Aloenxertos , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Metabolismo Energético , Desenho de Equipamento , Feminino , Glucose/farmacologia , Sobrevivência de Enxerto , Parada Cardíaca/induzido quimicamente , Hepatectomia/efeitos adversos , Fígado/metabolismo , Fígado/patologia , Testes de Função Hepática , Transplante de Fígado/efeitos adversos , Transplante de Fígado/métodos , Manitol/farmacologia , Teste de Materiais , Soluções para Preservação de Órgãos/farmacologia , Perfusão/efeitos adversos , Perfusão/métodos , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Sus scrofa , Fatores de Tempo , Sobrevivência de Tecidos , Isquemia Quente/efeitos adversos , Isquemia Quente/métodos
8.
PLoS One ; 7(11): e50235, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226251

RESUMO

Ischemia/reperfusion injury occurring during liver transplantation is mainly due to the generation of reactive oxygen species (ROS) upon revascularization. Thus, delivery of antioxidant enzymes might reduce the deleterious effects of ROS and improve liver graft initial function. Mangafodipir trisodium (MnDPDP), a contrast agent currently used in magnetic resonance imaging of the liver, has been shown to be endowed with powerful antioxidant properties. We hypothesized that MnDPDP could have a protective effect against liver ischemia reperfusion injury when administrated to the donor prior to harvesting. Livers from Sprague Dawley rats pretreated or not with MnDPDP were harvested and subsequently preserved for 24 h in Celsior® solution at 4°C. Organs were then perfused ex vivo for 120 min at 37°C with Krebs Henseleit solution. In MnDPDP (5 µmol/kg) group, we observed that ATP content was significantly higher at the end of the cold preservation period relative to untreated group. After reperfusion, livers from MnDPDP-treated rats showed better tissue integrity, less hepatocellular and endothelial cell injury. This was accompanied by larger amounts of bile production and higher ATP recovery as compared to untreated livers. The protective effect of MnDPDP was associated with a significant decrease of lipid peroxidation, mitochondrial damage, and apoptosis. Interestingly, MnDPDP-pretreated livers exhibited activation of Nfr2 and HIF-1α pathways resulting in a higher catalase and HO-1 activities. MnDPDP also increased total nitric oxide (NO) production which derived from higher expression of constitutive NO synthase and lower expression of inducible NO synthase. In conclusion, our results show that donor pretreatment with MnDPDP protects the rat liver graft from cold ischemia/reperfusion injury and demonstrate for the first time the potential interest of this molecule in the field of organ preservation. Since MnDPDP is safely used in liver imaging, this preservation strategy holds great promise for translation to clinical liver transplantation.


Assuntos
Antioxidantes/farmacologia , Ácido Edético/análogos & derivados , Transplante de Fígado , Fígado/efeitos dos fármacos , Soluções para Preservação de Órgãos/farmacologia , Disfunção Primária do Enxerto/prevenção & controle , Fosfato de Piridoxal/análogos & derivados , Espécies Reativas de Oxigênio/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/efeitos dos fármacos , Catalase/genética , Catalase/metabolismo , Ácido Edético/farmacologia , Expressão Gênica/efeitos dos fármacos , Sobrevivência de Enxerto/efeitos dos fármacos , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/imunologia , Masculino , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Técnicas de Cultura de Órgãos , Preservação de Órgãos , Soluções para Preservação de Órgãos/química , Disfunção Primária do Enxerto/imunologia , Disfunção Primária do Enxerto/metabolismo , Fosfato de Piridoxal/farmacologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Tolerância ao Transplante/efeitos dos fármacos
9.
World J Gastroenterol ; 16(45): 5693-700, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21128318

RESUMO

AIM: To investigate the benefits of insulin like growth factor-1 (IGF-1) supplementation to serum-free institut georges lopez-1 (IGL-1) solution to protect fatty liver against cold ischemia reperfusion injury. METHODS: Steatotic livers were preserved for 24 h in IGL-1 solution supplemented with or without IGF-1 and then perfused "ex vivo" for 2 h at 37degrees C. We examined the effects of IGF-1 on hepatic damage and function (transaminases, percentage of sulfobromophthalein clearance in bile and vascular resistance). We also studied other factors associated with the poor tolerance of fatty livers to cold ischemia reperfusion injury such as mitochondrial damage, oxidative stress, nitric oxide, tumor necrosis factor-α (TNF-α) and mitogen-activated protein kinases. RESULTS: Steatotic livers preserved in IGL-1 solution supplemented with IGF-1 showed lower transaminase levels, increased bile clearance and a reduction in vascular resistance when compared to those preserved in IGL-1 solution alone. These benefits are mediated by activation of AKT and constitutive endothelial nitric oxide synthase (eNOS), as well as the inhibition of inflammatory cytokines such as TNF-α. Mitochondrial damage and oxidative stress were also prevented. CONCLUSION: IGL-1 enrichment with IGF-1 increased fatty liver graft preservation through AKT and eNOS activation, and prevented TNF-α release during normothermic reperfusion.


Assuntos
Isquemia Fria , Fígado Gorduroso/cirurgia , Fator de Crescimento Insulin-Like I/farmacologia , Fígado/efeitos dos fármacos , Soluções para Preservação de Órgãos/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Bile/metabolismo , Isquemia Fria/efeitos adversos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado/irrigação sanguínea , Fígado/metabolismo , Fígado/patologia , Fígado/cirurgia , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Zucker , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/metabolismo , Resistência Vascular , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
10.
Liver Transpl ; 16(9): 1098-111, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20818748

RESUMO

This study examined the effects of epidermal growth factor (EGF) and insulin-like growth factor-I (IGF-I) supplementation to University of Wisconsin solution (UW) in steatotic and nonsteatotic livers during cold storage. Hepatic injury and function were evaluated in livers preserved for 24 hours at 4 degrees C in UW and in UW with EGF and IGF-I (separately or in combination) and then perfused ex vivo for 2 hours at 37 degrees C. AKT was inhibited pharmacologically. In addition, hepatic injury and survival were evaluated in recipients who underwent transplantation with steatotic and nonsteatotic livers preserved for 6 hours in UW and UW with EGF and IGF-I (separately or in combination). The results, based on isolated perfused liver, indicated that the addition of EGF and IGF-I (separately or in combination) to UW reduced hepatic injury and improved function in both liver types. A combination of EGF and IGF-I resulted in hepatic injury and function parameters in both liver types similar to those obtained by EGF and IGF-I separately. EGF increased IGF-I, and both additives up-regulated AKT in both liver types. This was associated with glycogen synthase kinase-3beta (GSK3(beta)) inhibition in nonsteatotic livers and PPAR gamma overexpression in steatotic livers. When AKT was inhibited, the effects of EGF and IGF-I on GSK3(beta), PPAR gamma, hepatic injury and function disappeared. The benefits of EGF and IGF-I as additives in UW solution were also clearly seen in the liver transplantation model, because the presence of EGF and IGF-I (separately or in combination) in UW solution reduced hepatic injury and improved survival in recipients who underwent transplantation with steatotic and nonsteatotic liver grafts. In conclusion, EGF and IGF-I may constitute new additives to UW solution in steatotic and nonsteatotic liver preservation, whereas a combination of both seems unnecessary.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Fígado Gorduroso/cirurgia , Fator de Crescimento Insulin-Like I/farmacologia , Transplante de Fígado , Fígado/efeitos dos fármacos , Fígado/cirurgia , Soluções para Preservação de Órgãos/farmacologia , Preservação de Órgãos/métodos , Traumatismo por Reperfusão/prevenção & controle , Adenosina/farmacologia , Alopurinol/farmacologia , Animais , Sobrevivência Celular , Isquemia Fria , Modelos Animais de Doenças , Fígado Gorduroso/patologia , Glutationa/farmacologia , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Insulina/farmacologia , Fígado/metabolismo , Fígado/patologia , Transplante de Fígado/efeitos adversos , PPAR gama/metabolismo , Perfusão , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rafinose/farmacologia , Ratos , Ratos Zucker , Proteínas Recombinantes/farmacologia , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/patologia , Fatores de Tempo
11.
World J Gastroenterol ; 16(28): 3499-509, 2010 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-20653058

RESUMO

AIM: To examine the relevance of hypoxia inducible factor (HIF-1) and nitric oxide (NO) on the preservation of fatty liver against cold ischemia-reperfusion injury (IRI). METHODS: We used an isolated perfused rat liver model and we evaluated HIF-1alpha in steatotic and non-steatotic livers preserved for 24 h at 4 degrees C in University of Wisconsin and IGL-1 solutions, and then subjected to 2 h of normothermic reperfusion. After normoxic reperfusion, liver enzymes, bile production, bromosulfophthalein clearance, as well as HIF-1alpha and NO [endothelial NO synthase (eNOS) activity and nitrites/nitrates] were also measured. Other factors associated with the higher susceptibility of steatotic livers to IRI, such as mitochondrial damage and vascular resistance were evaluated. RESULTS: A significant increase in HIF-1alpha was found in steatotic and non-steatotic livers preserved in IGL-1 after cold storage. Livers preserved in IGL-1 showed a significant attenuation of liver injury and improvement in liver function parameters. These benefits were enhanced by the addition of trimetazidine (an anti-ischemic drug), which induces NO and eNOS activation, to IGL-1 solution. In normoxic reperfusion, the presence of NO favors HIF-1alpha accumulation, promoting also the activation of other cytoprotective genes, such as heme-oxygenase-1. CONCLUSION: We found evidence for the role of the HIF-1alpha/NO system in fatty liver preservation, especially when IGL-1 solution is used.


Assuntos
Fígado Gorduroso/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Transplante de Fígado , Fígado/metabolismo , Óxido Nítrico/metabolismo , Animais , Isquemia Fria , Modelos Animais de Doenças , Glutamato Desidrogenase/metabolismo , Heme Oxigenase-1/metabolismo , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Óxido Nítrico Sintase Tipo III/metabolismo , Soluções para Preservação de Órgãos/farmacologia , Ratos , Ratos Zucker , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle
12.
Liver Transpl ; 16(2): 163-71, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20104484

RESUMO

Here we examine the effect of adding carvedilol (CVD) to University of Wisconsin (UW) solution on the preservation of steatotic and nonsteatotic livers during cold ischemia and after normothermic reperfusion. We used an isolated perfused rat liver model. The following protocols were evaluated. Protocol 1 concerned the effect of CVD after cold ischemia. Steatotic and nonsteatotic livers were preserved for 24 hours in UW solution alone or with CVD. Livers without cold ischemia were used as controls. Transaminases were evaluated in the flushing effluent. Protocol 2 involved the effect of CVD after reperfusion. Both liver types were preserved for 24 hours in UW solution alone or with CVD and then perfused ex vivo for 2 hours at 37 degrees C. Livers flushed and perfused without ischemia were used as controls. Hepatic injury and functionality [transaminases, bile production, and hepatic clearance of sulfobromophthalein (BSP)] were evaluated after reperfusion. In addition, factors potentially involved in hepatic ischemia-reperfusion injury, including oxidative stress (malondialdehyde and superoxide anion levels), mitochondrial damage (glutamate dehydrogenase activity), microcirculatory disorders (flow rate and vascular resistance), and adenosine triphosphate (ATP) depletion, were evaluated after reperfusion. After cold ischemia, steatotic livers preserved in UW solution showed higher transaminase levels than nonsteatotic livers. After reperfusion, steatotic livers preserved in UW solution showed higher transaminase levels and lower bile production and BSP clearance than nonsteatotic livers. Alterations in the perfusion flow rate and vascular resistance, mitochondrial damage, and reduced ATP content were more evident in steatotic livers preserved in UW solution. The addition of CVD to UW solution reduced hepatic injury, obstructed its mechanisms, and improved hepatic functionality in both liver types. We conclude that CVD is a useful additive for UW solution that improves the preservation of steatotic and nonsteatotic livers subjected to prolonged cold ischemia.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Carbazóis/farmacologia , Fígado Gorduroso/prevenção & controle , Transplante de Fígado , Soluções para Preservação de Órgãos/farmacologia , Preservação de Órgãos/métodos , Propanolaminas/farmacologia , Adenosina/farmacologia , Trifosfato de Adenosina/metabolismo , Adenilato Quinase/metabolismo , Alopurinol/farmacologia , Animais , Bile/metabolismo , Carvedilol , Temperatura Baixa , Glutationa/farmacologia , Insulina/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes de Função Hepática , Complicações Pós-Operatórias/prevenção & controle , Rafinose/farmacologia , Ratos , Ratos Zucker , Traumatismo por Reperfusão/prevenção & controle , Resistência Vascular/efeitos dos fármacos
13.
Endocrinology ; 150(7): 3153-61, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19282385

RESUMO

Hepatic steatosis is a major risk factor in ischemia-reperfusion (I/R). IGF-binding proteins (IGFBPs) modulate IGF-I action by transporting circulating IGF-I to its sites of action. Epidermal growth factor (EGF) stimulates IGF-I synthesis in vitro. We examined the effect of IGF-I and EGF treatment, separately or in combination, on the vulnerability of steatotic livers to I/R. Our results indicated that I/R impaired IGF-I synthesis only in steatotic livers. Only when a high dose of IGF-I (400 microg/kg) was given to obese animals did they show high circulating IGF-I:IGFBP levels, increased hepatic IGF-I levels, and protection against damage. In lean animals, a dose of 100 microg/kg IGF-I protected nonsteatotic livers. Our results indicated that the combined administration of IGF-I and EGF resulted in hepatic injury parameters in both liver types similar to that obtained by IGF-I and EGF separately. IGF-I increased egf expression in both liver types. The beneficial role of EGF on hepatic I/R injury may be attributable to p38 inhibition in nonsteatotic livers and to PPAR gamma overexpression in steatotic livers. In conclusion, IGF-I and EGF may constitute new pharmacological strategies to reduce the inherent susceptibility of steatotic livers to I/R injury.


Assuntos
Fator de Crescimento Epidérmico/uso terapêutico , Fígado Gorduroso/complicações , Fator de Crescimento Insulin-Like I/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Animais , Fator de Crescimento Epidérmico/administração & dosagem , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/administração & dosagem , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , PPAR gama/fisiologia , Ratos , Ratos Zucker , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
14.
Liver Transpl ; 13(3): 410-25, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17326058

RESUMO

This study investigates how the addition of trimetazidine (TMZ) and aminoimidazole-4-carboxamide ribonucleoside (AICAR) to University of Wisconsin (UW) solution protects steatotic livers. Steatotic and nonsteatotic livers were preserved for 24 hours at 4 degrees C in UW and UW with TMZ and AICAR (separately or in combination) and then perfused ex vivo for 2 hours at 37 degrees C. Adenosine monophosphate-activated protein kinase (AMPK) or nitric oxide (NO) synthesis inhibition in livers preserved in UW with TMZ was also investigated. Hepatic injury and function (transaminases, bile production, and sulfobromophthalein clearance) and factors potentially involved in the susceptibility of steatotic livers to ischemia-reperfusion (I/R), including vascular resistance, mitochondrial damage, adenosine triphosphate depletion, and oxidative stress were evaluated. AMPK, NO synthase (NOS), nitrate, and nitrite levels were also determined. The addition of TMZ and AICAR (separately or in combination) to UW reduced hepatic injury, improved functionality, and protected against the mechanisms responsible for the vulnerability of steatotic livers to I/R. Like AICAR, TMZ increased AMPK, constitutive NOS, and nitrates and nitrites, and conversely, AMPK or NO synthesis inhibition abolished the benefits of TMZ. In conclusion, TMZ, by means of AMPK, increased NO, thus protecting steatotic livers against their vulnerability to I/R injury. TMZ and AICAR may constitute new additives to UW solution in steatotic liver preservation, whereas a combination of both seems unnecessary.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Ativadores de Enzimas/uso terapêutico , Fígado Gorduroso/prevenção & controle , Complexos Multienzimáticos/fisiologia , Soluções para Preservação de Órgãos/uso terapêutico , Proteínas Serina-Treonina Quinases/fisiologia , Ribonucleotídeos/uso terapêutico , Trimetazidina/uso terapêutico , Proteínas Quinases Ativadas por AMP , Nucleotídeos de Adenina/metabolismo , Adenosina/uso terapêutico , Alopurinol/uso terapêutico , Aminoimidazol Carboxamida/uso terapêutico , Animais , Glutationa/uso terapêutico , Insulina/uso terapêutico , Fígado/enzimologia , Fígado/fisiologia , Mitocôndrias Hepáticas/fisiologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/metabolismo , Estresse Oxidativo/fisiologia , Rafinose/uso terapêutico , Ratos , Ratos Zucker , Traumatismo por Reperfusão/prevenção & controle , Resistência Vascular/fisiologia
15.
Am J Pathol ; 168(5): 1474-85, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16651615

RESUMO

Ischemic preconditioning protects steatotic livers against ischemia-reperfusion (I/R) injury, but just how this is achieved is poorly understood. Here, I/R or preconditioning plus I/R was induced in steatotic and nonsteatotic livers followed by investigating the effect of pharmacological treatments that modulate heat shock proteins (HSPs) and mitogen-activated protein kinases (MAPKs). MAPKs, HSPs, protein kinase C, and transaminase levels were measured after reperfusion. We report that preconditioning increased HSP72 and heme-oxygenase-1 (HO-1) at 6 and 24 hours of reperfusion, respectively. Unlike nonsteatotic livers, steatotic livers benefited from HSP72 activators (geranylgeranylacetone) throughout reperfusion. This protection seemed attributable to HO-1 induction. In steatotic livers, preconditioning and geranylgeranylacetone treatment (which are responsible for HO-1 induction) increased protein kinase C activity. HO-1 activators (cobalt(III) protoporphyrin IX) protected both liver types. Preconditioning reduced p38 MAPK and c-Jun N-terminal kinase (JNK), resulting in HSP72 induction though HO-1 remained unmodified. Like HSP72, both p38 and JNK appeared not to be crucial in preconditioning, and inhibitors of p38 (SB203580) and JNK (SP600125) were less effective against hepatic injury than HO-1 activators. These results provide new data regarding the mechanisms of preconditioning and may pave the way to the development of new pharmacological strategies in liver surgery.


Assuntos
Fígado Gorduroso/metabolismo , Proteínas de Choque Térmico/metabolismo , Precondicionamento Isquêmico , Fígado/irrigação sanguínea , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Traumatismo por Reperfusão/metabolismo , Animais , Heme Oxigenase-1/metabolismo , Fígado/patologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Óxido Nítrico/fisiologia , Proteína Quinase C/metabolismo , Ratos , Ratos Zucker , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Fatores de Tempo
16.
Liver Transpl ; 12(8): 1215-23, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16724331

RESUMO

A new Institut Georges Lopez (IGL-1) solution was used to preserve steatotic livers. Steatotic (obese [Ob]) and nonsteatotic (lean [Ln]) livers from Zücker rats (n = 16, 8 Ln and 8 Ob) were preserved for 24 hours at 4 degrees C in University of Wisconsin (UW) or IGL-1 solution, respectively, and then perfused ex vivo for 2 hours at 37 degrees C. Additionally, Ob and Ln livers (n = 16, 8 Ln and 8 Ob) were preserved in IGL-1 plus Nomega-nitro-L-arginine methyl ester hydrochloride (L-NAME). Hepatic injury and function (aminotransferases, bile production, bromosulfophthalein clearance), and factors potentially involved in the susceptibility of steatotic livers to ischemia-reperfusion injury, such as oxidative stress, mitochondrial damage, and vascular resistance, were studied. Nitric oxide (NO) production and constitutive and inducible NO synthase were also measured. Steatotic and nonsteatotic livers preserved in IGL-1 solution showed lower transaminases, malondialdehyde, glutamate dehydrogenase levels, and higher bile production than UW-solution-preserved livers. IGL-1 solution protected against oxidative stress, mitochondrial damage and the alterations in vascular resistance associated with cold ischemia-reperfusion. Thus, at the end of reperfusion period, aspartate aminotransferase levels in steatotic livers were 281 +/- 6 U/L in UW vs. 202 +/- 10 U/L in IGL-1 solution. Glutamate dehydrogenase was 463 +/- 75 U/L in UW vs. 111 +/- 4 U/L in IGL-1 solution, and oxidative stress was 3.0 +/- 0.1 nmol/mg prot in UW vs. 2.0 +/- 0.1 nmol/mg prot in IGL-1 solution. These beneficial effects of IGL-1 solution were abolished by the addition of L-NAME, which implicates NO in the benefits of IGL-1. In conclusion, IGL-1 solution provided steatotic livers with better protection against the deleterious effects of cold ischemia-reperfusion injury than did UW solution.


Assuntos
Fígado Gorduroso/metabolismo , Fígado/metabolismo , Soluções para Preservação de Órgãos/metabolismo , Preservação de Órgãos/métodos , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Bile/metabolismo , Fígado Gorduroso/patologia , Glutamato Desidrogenase/metabolismo , Fígado/patologia , Testes de Função Hepática , Malondialdeído/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Obesidade/metabolismo , Soluções para Preservação de Órgãos/química , Ratos , Ratos Zucker , Reperfusão , Temperatura , Resistência Vascular
17.
World J Gastroenterol ; 12(6): 908-14, 2006 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-16521219

RESUMO

AIM: Chronic organ-donor shortage has led to the acceptance of steatotic livers for transplantation, despite the higher risk of graft dysfunction or nonfunction associated with the ischemic preservation period of these organs. The present study evaluates the effects of trimetazidine (TMZ) on an isolated perfused liver model. METHODS: Steatotic and non-steatotic livers were preserved for 24 h in the University of Wisconsin (UW) solution with or without TMZ. Hepatic injury and function (transaminases, bile production and sulfobromophthalein (BSP) clearance) and factors potentially involved in the susceptibility of steatotic livers to ischemia-reperfusion (I/R) injury, including oxidative stress, mitochondrial damage, microcirculatory diseases, and ATP depletion were evaluated. RESULTS: Steatotic livers preserved in UW solution showed higher transaminase levels, lower bile production and BSP clearance compared with non-steatotic livers. Alterations in perfusion flow rate and vascular resistance, mitochondrial damage, and reduced ATP content were more evident in steatotic livers. TMZ addition to UW solution reduced hepatic injury and ameliorated hepatic functionality in both types of the liver and protected against the mechanisms potentially responsible for the poor tolerance of steatotic livers to I/R. CONCLUSION: TMZ may constitute a useful approach in fatty liver surgery, limiting the inherent risk of steatotic liver failure following transplantation.


Assuntos
Fígado Gorduroso/etiologia , Transplante de Fígado/efeitos adversos , Trimetazidina/uso terapêutico , Vasodilatadores/uso terapêutico , Animais , Fígado Gorduroso/tratamento farmacológico , Obesidade , Ratos , Ratos Mutantes , Ratos Zucker , Transplante Homólogo/efeitos adversos
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