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1.
Chinese Journal of Hepatology ; (12): E002-E002, 2020.
مقالة ي صينى | WPRIM | ID: wpr-811670

الملخص

Objective@#To explore and analyze the possible mechanism of liver injury in patients with coronavirus disease 2019 (novel coronavirus pneumonia, NCP).@*Methods@#The correlation between ALT, AST and other liver enzyme changes condition and NCP patients’ disease status reported in the literature was comprehensively analyzed. ACE2 expression in liver tissue for novel coronavirus was analyzed based on single cell sequencing (GSE115469) data. RNA-Seq method was used to analyze Ace2 expression and transcription factors related to its expression in liver tissues at various time-points after hepatectomy in mouse model of acute liver injury with partial hepatectomy. t-test or Spearman rank correlation analysis was used for statistical analysis.@*Results@#ALT and AST were abnormally elevated in some patients with novel coronavirus infection, and the rate and extent of ALT and AST elevation in severe NCP patients were higher than those in non-severe patients. Liver tissue results of single cell sequencing and immunohistochemistry showed that ACE2 was only expressed in bile duct epithelial cells of normal liver tissues, and very low in hepatocytes. In a mouse model of acute liver injury with partial hepatectomy, Ace2 expression was down-regulated on the first day, but it was elevated up to twice of the normal level on the third day, and returned to normal level on seventh day when the liver recovered and hepatocyte proliferation stopped. Whether this phenomenon suggests that the bile duct epithelial cells with positive expression of Ace2 participate in the process of liver regeneration after partial hepatectomy deserves further study. In RNA-Seq data, 77 transcription factors were positively correlated with the expression of ACE2 (r > 0.2, FDR < 0.05), which were mainly enriched in the development, differentiation, morphogenesis and cell proliferation of glandular epithelial cells.@*Conclusion@#We assumed that in addition to the over activated inflammatory response in patients with NCP, the up-regulation of ACE2 expression in liver tissue caused by compensatory proliferation of hepatocytes derived from bile duct epithelial cells may also be the possible mechanism of liver tissue injury caused by 2019 novel coronavirus infection.

2.
Chinese Journal of Hepatology ; (12): E002-E002, 2020.
مقالة ي صينى | WPRIM | ID: wpr-787636

الملخص

To explore and analyze the possible mechanism of liver injury in patients with coronavirus disease 2019 (novel coronavirus pneumonia, NCP). The correlation between ALT, AST and other liver enzyme changes condition and NCP patients' disease status reported in the literature was comprehensively analyzed. ACE2 expression in liver tissue for novel coronavirus was analyzed based on single cell sequencing (GSE115469) data. RNA-Seq method was used to analyze Ace2 expression and transcription factors related to its expression in liver tissues at various time-points after hepatectomy in mouse model of acute liver injury with partial hepatectomy. -test or Spearman rank correlation analysis was used for statistical analysis. ALT and AST were abnormally elevated in some patients with novel coronavirus infection, and the rate and extent of ALT and AST elevation in severe NCP patients were higher than those in non-severe patients. Liver tissue results of single cell sequencing and immunohistochemistry showed that ACE2 was only expressed in bile duct epithelial cells of normal liver tissues, and very low in hepatocytes. In a mouse model of acute liver injury with partial hepatectomy, Ace2 expression was down-regulated on the first day, but it was elevated up to twice of the normal level on the third day, and returned to normal level on seventh day when the liver recovered and hepatocyte proliferation stopped. Whether this phenomenon suggests that the bile duct epithelial cells with positive expression of Ace2 participate in the process of liver regeneration after partial hepatectomy deserves further study. In RNA-Seq data, 77 transcription factors were positively correlated with the expression of ACE2 (r > 0.2, FDR < 0.05), which were mainly enriched in the development, differentiation, morphogenesis and cell proliferation of glandular epithelial cells. We assumed that in addition to the over activated inflammatory response in patients with NCP, the up-regulation of ACE2 expression in liver tissue caused by compensatory proliferation of hepatocytes derived from bile duct epithelial cells may also be the possible mechanism of liver tissue injury caused by 2019 novel coronavirus infection.

3.
Rev. Col. Bras. Cir ; 39(3): 211-215, maio-jun. 2012. tab
مقالة ي البرتغالية | LILACS | ID: lil-643150

الملخص

OBJETIVO: Avaliar a regeneração hepática com modulação pelo pré-condicionamento isquêmico após isquemia, reperfusão e hepatectomia parcial. MÉTODOS: Foram usadas 24 ratas Wistar, de 12 semanas de idade, distribuídas randomicamente em quatro grupos: Grupo Controle (SHAM), Grupo Hepatectomia (HEP), Grupo Isquemia e Reperfusão (GIR) e Grupo Pré-condicionamento Isquêmico (PRE). Foi feita a análise das enzimas hepáticas ALT e AST, avaliação da regeneração através dos pesos inicial e final do fígado e da proliferação dos hepatócitos pela análise imunoistoquímica com o Proliferating Cell Nuclear Antigen (PCNA). RESULTADOS: Em todos os grupos ocorreu regeneração do fígado, não havendo significância estatística entre eles. Houve diferenças significativas em relação a ALT e AST entre os grupos HEP-SHAM, GIR-PRE, GIR-SHAM E PRE-SHAM (p< 0,05). Também houve diferença significativa em relação à marcação de PCNA do grupo SHAM quando comparado aos demais grupos (p< 0,05). CONCLUSÃO: O pré-condicionamento isquêmico diminuiu a lesão hepática, mas não influenciou na regeneração até 48 horas.


OBJECTIVE: To evaluate liver regeneration modulated by ischemic preconditioning after ischemia, reperfusion and partial hepatectomy. METHODS: We used 24 Wistar rats of 12 weeks of age, which were randomly assigned into four groups: control (SHAM), hepatectomy (HEP), ischemia and reperfusion (IRG) and Ischemic Preconditioning (SRG). Analyses were made on liver enzymes ALT and AST, assessment of regeneration through the initial and final weight of the liver and the proliferation of hepatocytes by immunohistochemical analysis with Proliferating Cell Nuclear Antigen (PCNA). RESULTS: In all groups there was liver regeneration, with no statistically significant difference between them. There were significant differences in ALT and AST between groups HEP and SHAM, PRE and GIR, GIR and SHAM and PRE and SHAM (p <0.05). There were also significant differences in the PCNA labeling of the SHAM group as compared to other groups (p <0.05). CONCLUSION: The ischemic preconditioning decreased liver injury, but did not influence the regeneration up to 48 hours.


الموضوعات
Animals , Rats , Hepatectomy/methods , Ischemic Preconditioning , Liver Regeneration , Rats, Wistar , Reperfusion Injury
4.
ABCD (São Paulo, Impr.) ; 24(2): 144-151, abr.-jun. 2011. ilus, tab
مقالة ي البرتغالية | LILACS | ID: lil-592484

الملخص

RACIONAL: O fígado adulto normal é quiescente e apenas uma pequena porcentagem das suas células é submetida à divisão celular em qualquer tempo, mas pode rapidamente iniciar a proliferação celular em resposta a um estímulo. Este processo pode ser desencadeado através da hepatectomia parcial. OBJETIVOS: Avaliar o efeito da hipertensão portal provocada pela oclusão parcial da drenagem venosa hepática sobre a regeneração do fígado remanescente de ratos submetidos à hepatectomia parcial. MÉTODOS: Foram realizadas hepatectomias a dois terços em 50 ratos Wistar machos adultos. Os animais foram divididos em cinco grupos: um grupo controle e quatro grupos de estudo que foram submetidos a diferentes graus de plicatura da veia cava inferior supra-hepática. Após 240 horas do estímulo para regeneração realizou-se nova laparotomia com aferição das pressões portal e de veia cava inferior, além de biópsia hepática. Analisaram-se os fragmentos por imunoistoquímica para os marcadores Ki-67 e fator de von Willebrand. A deposição de colágeno foi avaliada pela coloração tricrômico de Masson e a função hepática através de marcadores sorológicos. RESULTADOS: A proliferação celular nos animais submetidos à hepatectomia parcial e hipertensão portal de diversos graus persistiu mais elevada quando comparada ao grupo controle. O índice de proliferação para Ki-67 estava mais elevado nos grupos submetidos à elevação da pressão portal. A expressão do fator de von Willebrand estava acentuadamente elevada após a hepatectomia parcial nos grupos com maior grau de hipertensão portal. Houve pouco depósito de colágeno no tecido hepático nos animais dos quatro grupos com plicatura parcial da veia cava inferior supra-hepática, porém a deposição foi mais intensa nos grupos com níveis de pressão portal menores. CONCLUSÕES: Ratos submetidos à hepatectomia parcial a 70 por cento e hipertensão portal, após 240 horas, apresentam: 1. atraso no processo regenerativo diretamente proporcional aos...


BACKGROUND: The normal adult liver is quiescent and only a small percentage of its cells is subjected to cell division at any time, but can quickly initiate cell proliferation in response to a stimulus. This process can be triggered by partial hepatectomy. AIM: To evaluate the effect of portal hypertension caused by partial occlusion of hepatic venous drainage on regeneration of remnant liver of rats after partial hepatectomy. METHODS: It was performed two-thirds hepatectomy in 50 adult male Wistar rats. The animals were divided into five groups: a control group and four study groups were subjected to different degrees of plication of inferior vena cava-hepatic above. After 240 hours of the stimulus for regeneration took place relaparotomy with measurement of portal pressure and inferior vena cava, and liver biopsy. Fragments were analyzed by immunohistochemistry for the markers Ki-67 and von Willebrand factor. The collagen deposition was evaluated by Masson's trichrome staining and liver function using serological markers. RESULTS: Cell proliferation in animals subjected to partial hepatectomy and portal hypertension persisted in varying degrees higher when compared to the control group. The proliferation index for Ki-67 was higher in the groups submitted to the elevation of portal pressure. The expression of von Willebrand factor was markedly elevated after partial hepatectomy in groups with higher degree of portal hypertension. There was little collagen deposition in liver tissue in animals of the four groups with partial plication of the inferior vena cava above-liver, but the deposition was more intense in the group with lower portal pressure. CONCLUSIONS: Rats underwent 70 percent partial hepatectomy and portal hypertension, after 240 hours, presented: 1. delay in the regenerative process directly proportional to pressure levels in the portal system; 2. after ten days, there was the proliferation of hepatocytes proportionally more intense...


الموضوعات
Animals , Male , Rats , Immunohistochemistry , Liver/surgery , Liver/pathology , Hepatectomy/methods , Hypertension, Portal , Laparotomy , Liver Regeneration
5.
Rio de Janeiro; s.n; 2011. 89 f p.
أطروحة جامعية ي البرتغالية | LILACS | ID: lil-756245

الملخص

A fibrose hepática é o resultado de uma lesão crônica, com a ativação de células inflamatórias e fibrogênicas no fígado, as quais levam a um acúmulo excessivo de proteínas de matriz extracelular (MEC). Essas alterações resultam na morte de células do fígado, com desorganização e perda da função do parênquima hepático. A cirrose é o estágio avançado da fibrose, e culmina na falência hepática, uma condição potencialmente fatal cujo único tratamento efetivo é o transplante de fígado, o qual é limitado pela disponibilidade de órgãos. Na busca por terapias alternativas visando a regeneração hepática, o transplante de células mononucleares de medula óssea (CMMO) mostrou resultados benéficos e promissores em modelos animais e alguns protocolos clínicos. Entre essas células, estão as células-tronco hematopoiéticas e mesenquimais, que apresentam potencial regenerativo e modulador da resposta inflamatória. Este estudo pretendeu avançar na compreensão dos mecanismos pelos quais as CMMO podem ajudar na regeneração hepática. Ratos com fibrose hepática induzida por ligadura do ducto biliar (LDB) foram transplantados com CMMO e comparados com ratos com fibrose sem transplante e ratos normais. Parâmetros hepáticos como componentes da MEC (colágeno total, colágenos tipos I e IV, laminina, metaloproteinases de matriz – MMPs), componentes celulares (células fibrogênicas, células de Kupffer e colangiócitos) e enzimas hepáticas foram analisados por microscopia de luz, microscopia confocal, western blotting e espectrofotometria. Os resultados mostraram que o transplante de CMMO contribui para a regeneração hepática de maneira global, (a) diminuindo o acúmulo de colágeno e laminina; (b) aumentando a produção de MMPs que favorecem o remodelamento da MEC, principalmente por células de Kupffer; (c) normalizando a quantidade de colangiócitos e diminuindo a quantidade de células fibrogênicas; e (d) normalizando os níveis sanguíneos das enzimas hepáticas...


Liver fibrosis results from a chronic injury, with the activation of hepatic inflammatory and fibrogenic cells, which lead to an excessive extracellular matrix (MEC) protein accumulation. These alterations result in the death of liver cells, along with disorganization and loss of function of the hepatic parenchyma. Cirrhosis is the advanced stage of fibrosis, and culminates in hepatic failure, a potentially fatal condition whose only effective treatment is liver transplantation, which is limited by organ shortage. Amid the search for alternative therapies aiming hepatic regeneration, bone marrow mononuclear cell (CMMO) transplantation has shown promising and benefic results in animal models and some clinical protocols. Amongst these cells are hematopoietic and mesenchymal stem cells, which present regenerative potential and modulate inflammatory response. This study aimed to add knowledge on the mechanisms by which CMMO may prompt hepatic regeneration. Rats with liver fibrosis induced by bile duct ligation (LDB) were transplanted with CMMO and compared to fibrotic and normal rats without transplantation. Hepatic parameters such as MEC components (total collagen, collagens types I and IV, laminin and matrix metalloproteinases – MMPs), cellular components (fibrogenic and Kupffer cells, cholangiocytes) and liver enzymes were analyzed through confocal, fluorescence and light microscopy, western blotting and spectrophotometry. Results showed that CMMO contribute to liver regeneration globally, (a) reducing collagen and laminin accumulation; (b) increasing MMP production, specially by Kupffer cells, that favor MEC remodeling; (c) normalizing cholangiocyte numbers and reducing fibrogenic cells; and (d) normalizing plasma levels of hepatic enzymes...


الموضوعات
Humans , Animals , Rats , Bone Marrow , Extracellular Matrix , Liver Cirrhosis , Liver Regeneration , Collagen , Common Bile Duct/surgery , Fluorescent Antibody Technique , Liver/pathology , Kupffer Cells , Rats, Wistar
6.
مقالة ي صينى | WPRIM | ID: wpr-384970

الملخص

Objective To evaluate the effects of branched-chain amino acids-enriched early parenteral and enteral nutrition on the liver function and serum aminograms in cirrhotic rats after partial hepatectomy. Methods In this prospective randomized controlled study, 24 cirrhotic rats, induced by thioacetamide, were randomized into three groups: enteral nutrition (EN) group, EN + branched-chain amino acid (BCAA) group, and parenteral nutrition (PN) + BCAA group. After receiving partial hepatectomy, rats in all three groups were nutritionally supported with equal amount of calorie and nitrogen contents from the 1st postoperative day ( PO day 1 ) to PO day 5. On PO day 6, parameters including body weight, liver functions, prealbumin, transferring, and serum aminograms were measured or determined, and the level of liver albumin mRNA was detected by reversal transcription-polymerase chain reaction and morphological examinations such as HE staining and immunohistochemical staining, which were assessed by index of Ki67 protein index. Results Body weight was significantly decreased in all three groups on PO day 6 (P <0.05 ). Compared with EN + BCAA group, serum aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase after partial hepatectomy were significantly higher in PN + BCAA group (P <0.05 ). Serum alkaline phosphatase level was significantly higher in PN + BCAA group than in EN group ( P <0. 05). The level of prealbumin was significantly lower in PN + BCAA group when compared with EN group or EN +BCAA group ( both P < 0. 05 ), although no such significant difference was noted in terms of transferrin ( P >0. 05 ). The levels of leucine and isoleucine elevated while those of tyrosine, phenylalanine, arginine and tryptophan declined in PN + BCAA group or EN + BCAA group when compared with EN group ( P < 0. 05 ). Aminograms were not significantly different between EN + BCAA group and PN + BCAA group ( P > 0. 05 ). Levels of total amino acid and aromatic amino acid (AAA) were significantly lower while BCAA and ratio between BCAA and AAA (BCAA/AAA) were significantly higher in PN + BCAA group or EN + BCAA group than in EN group (P < 0. 05 ).Significantly lower level of albumin mRNA and index of Ki67 were observed in PN + BCAA group than in EN group or EN + BCAA group (P < 0.05 ) on PO day 6. Conclusions BCAA-enriched EN or PN reverses amino acid disequilibrium and restores BCAA/AAA in cirrhotic rats after partial hepatectomy. Compared with PN, EN is superior in improving postoperative liver function, promoting protein synthesis, and speed up tissue regeneration in the postoperative liver. However, it still can not restore serum albumin in a short term.

7.
ABCD (São Paulo, Impr.) ; 22(2): 89-95, abr.-jun. 2009. ilus, tab
مقالة ي البرتغالية | LILACS | ID: lil-555573

الملخص

INTRODUÇÃO: A regeneração hepática é um mecanismo para superar a perda de tecido funcional do fígado. Este processo é estudado através de diferentes métodos. OBJETIVO: Avaliar o efeito da oclusão parcial da drenagem venosa hepática sobre a regeneração do fígado remanescente de ratos submetidos à hepatectomia parcial. MÉTODO: Foram colhidas biópsias de fígado em 30 ratos Wistar machos, e a seguir realizada hepatectomia a dois terços. Os animais foram divididos em três grupos: um grupo controle e dois grupos de estudo, submetidos a diferentes graus de estenose da veia hepática direita. Após 96 horas do estímulo para regeneração hepática, todos submeteram-se à outra biópsia hepática. Analisaram-se os fragmentos por imunoistoquímica para os marcadores Ki-67 e fator de von Willebrand. Para a leitura das amostras utilizou-se o sistema SAMBA 4000. A deposição de colágeno foi avaliada pela coloração tricrômico de Masson. RESULTADOS: A proliferação celular dos animais submetidos à hepatectomia parcial e estenose moderada ou severa da veia hepática direita persistiu mais elevada quando comparada ao grupo controle. O Índice de Marcação para o Ki-67 foi significativamente mais elevado após a hepatectomia nos grupos submetidos à oclusão parcial da veia hepática, tanto moderada quanto severa. A expressão de fator de von Willebrand estava diminuída após a hepatectomia parcial nos três grupos. Houve pouco depósito de colágeno no tecido hepático nos animais dos dois grupos com estenose da veia hepática direita. CONCLUSÃO: A oclusão parcial da drenagem venosa hepática em ratos submetidos à hepatectomia parcial prolonga o tempo de proliferação de células hepáticas quando comparado aos animais com veias de calibre normal. Como consequência, também houve atraso na restauração da matriz extracelular e na formação de novos vasos sinusoidais.


BACKGROUND: Hepatic regeneration is a mechanism to overcome the loss of liver functional tissue. This process has been studied through different methods. AIM: To evaluate the effect of the partial occlusion of the hepatic venous drainage on the regeneration of the remainder livers in rats submitted to partial hepatectomy. METHOD: Liver biopsies from 30 male Wistar rats were collected, and after they were submitted two-third hepatectomy. The animals were divided in three groups: a control group and two study groups, which were submitted to different degrees of the right hepatic vein stenosis. After 96 hours of the stimulation for regeneration all rats were submitted to another hepatic biopsy. The analysis of the fragments was performed by immunohistochemistry for the Ki-67 and von Willebrand factor markers. The reading of the samples was done using the SAMBA 4000 system. Collagen deposition was evaluated by the trichromic Masson's staining. RESULT: The cellular proliferation of the animals submitted to partial hepatectomy and stenosis of the right hepatic vein persists higher when compared to control group. The Label Index for Ki-67 was significantly higher post-hepatectomy in groups submitted to hepatic vein partial occlusion. The expression of von Willebrand factor was strongly decreased after the hepatectomy in all groups. There was little deposit of collagen in the hepatic tissue of animals with hepatic vein stenosis. CONCLUSION: Partial occlusion of the hepatic venous drainage in rats submitted to partial hepatectomy prolongs the time of hepatic cells proliferation when compared to the animals with vein of normal caliber. Consequently, there will be also a delay in the restoration of the extracellular matrix and in the formation of new sinusoidal vessels.


الموضوعات
Animals , Male , Adult , Rats , Immunohistochemistry , Microcirculation , Mesenteric Vascular Occlusion , Rats, Wistar , Liver Regeneration , Liver/blood supply
8.
مقالة ي صينى | WPRIM | ID: wpr-545554

الملخص

Objective To study the relationship between hepatic resection,hepatic regeneration and hepatic function.Methods Totally 8 cases undergone partial hepatic resection were undergone CT scan pre-and pastoperation.The volumes of the whole liver and the lesions were measured on CT images,and the hepatic resectable rate was calculated before operation.The volume of liver was measured again after operation,and the hepatic regenerative rate at different time was also calculated after operation.The hepatic function was tested before and after operation.Results The negative relation was showed between hepatic resectable rate and hepatic regenerative rate.Conclusion There is postiive relation between hepatic resectable rate and the function of liver.

9.
مقالة ي البرتغالية | LILACS-Express | LILACS, VETINDEX | ID: biblio-1455996

الملخص

The authors prepared a detaile review of experimental surgical models of acute liver failure. They comment on the aspects of experimental induction, the advantages and disadvantages of the different models, as well as on the possibilities of diagnosis and treatment.


Os autores fazem uma revisão pormenorizada sobre os principais modelos cirúrgicos experimentais de falência hepática fulminante. Abordam aspectos da indução experimental das vantagens e desvantagens dos diferentes modelos, tecendo comentários sobre os modelos de indução da falência hepática, e das possíveis formas de diagnóstico e tratamento.

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