transforming-growth-factor-beta and Hepatic-Encephalopathy

Minimal hepatic encephalopathy (MHE) is associated with changes in the immune system including an increased pro-inflammatory environment and altered differentiation of CD4+ T lymphocytes. The mechanisms remain unknown. Changes in extracellular vesicle (EV) cargo including proteins and miRNAs could play a main role as mediators of immune system changes associated with MHE. The aim was to assess whether plasma EVs from MHE patients played a role in inducing the pro-inflammatory environment and altered differentiation of CD4+ T lymphocyte subtypes in MHE patients. We characterized the miRNA and protein cargo of plasma EVs from 50 cirrhotic patients (27 without and 23 with MHE) and 24 controls. CD4+ T cells from the controls were cultured with plasma EVs from the three groups of study, and the cytokine release and differentiation to CD4+ T-cell subtypes were assessed. Plasma EVs from MHE patients had altered miRNA and protein contents, and were enriched in inflammatory factors compared to the controls and patients without MHE. EVs from MHE patients modulated the expression of pro-inflammatory IL-17, IL-21, and TNF-α and anti-inflammatory TGF-β in cultured CD4+ T lymphocytes, and increased the proportion of Th follicular and Treg cells and the activation of Th17 cells. In conclusion, plasma EVs could play an important role in the induction of immune changes observed in MHE.

Topics: Cytokines; Extracellular Vesicles; Hepatic Encephalopathy; Humans; Interleukin-17; Liver Cirrhosis; MicroRNAs; T-Lymphocytes, Helper-Inducer; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

In the liver, transforming growth factor (TGF) -beta(1)is primarily responsible for activation of fat-storing cells, which are the main source of extracellular matrix proteins. Their deposition play a key role in the development of liver cirrhosis. The aim of this study was to evaluate plasma TGF-beta(1)in patients with different stages of liver cirrhosis and its possible use as an indicator of liver function impairment. TGF-beta(1)was measured in the plasma of 40 patients with liver cirrhosis. To estimate possible effect of liver insufficiency on plasma TGF-beta(1), patients were divided into three groups: A, B and C, univocal with Child-Pugh classes. Normal values were collected from 13 healthy volunteers. Liver cirrhosis resulted in a significant increase of plasma concentration of TGF-beta(1)(39.3+/-3.8 ng/ml), which doubled normal values (18.3+/-1.6 ng/ml). The highest concentrations were observed in alcoholic patients (44.4+/-4.7 ng/ml). TGF-beta(1)level increased depending on the degree of liver insufficiency, demonstrated by a significant positive correlation with Child-Pugh score (r=0.591). Values in group A were similar to normal, but were significantly elevated in groups B and C. These findings suggest possible use of plasma TGF-beta(1)measurement as an indicator of liver function impairment and possible marker of hepatic fibrosis progression in cirrhotic patients.

Topics: Alanine Transaminase; Aspartate Aminotransferases; Bilirubin; Biomarkers; Female; Hepatic Encephalopathy; Humans; Liver Cirrhosis; Liver Cirrhosis, Alcoholic; Liver Function Tests; Male; Middle Aged; Prothrombin Time; Reference Values; Transforming Growth Factor beta

We earlier described a model of fulminant hepatic failure (FHF) in the rat where partial hepatectomy is combined with induction of right liver lobe necrosis. In FHF rats, lack of regeneration of the residual liver was associated with delayed expression of HGF and HGF receptor c-met and elevated blood HGF and TGF-beta1 levels. We then found that intrasplenic hepatocyte transplantation prolonged survival in FHF rats and triggered hepatocyte proliferation in the native liver. The latter effect was associated with accelerated expression of HGF and c-met mRNA in the liver and lowering of blood HGF and TGF-beta1 levels. In the present study we show that in FHF rats, treatment with a bioartificial liver (BAL) had similar effects.. FHF was induced in inbred Lewis rats and after 4 h, Group 1 rats were subjected to a 4-h whole blood perfusion through the BAL loaded with 3 x 10(8) microcarrier-attached syngeneic hepatocytes, whereas Group 2 control rats were treated with the BAL containing microcarriers only.. Compared to sham-BAL-treated rats, the test rats lived longer (28 +/- 5 vs 17 +/- 2 h; P = 0.0005), had better coagulation parameters, maintained higher body core temperature, and showed decreased plasma TGF-beta1 levels. In addition, their liver remnants were HGF positive and showed increased DNA binding of transcription factors engaged in the modulation of hepatocyte proliferation (e.g., STAT3) and liver-specific gene expression (e.g., HNF1, HNF4, C/EBP).. This study demonstrates that hepatocyte-based extracorporeal support not only can provide metabolic support by increasing the available functional liver mass but also is capable of modifying humoral and molecular mechanisms which are responsible for proliferation and organ-specific functions of residual hepatocytes.

Topics: Animals; DNA; Electrophoresis, Polyacrylamide Gel; Extracorporeal Circulation; Hepatic Encephalopathy; Hepatocyte Growth Factor; Liver, Artificial; Male; Proto-Oncogene Proteins c-met; Rats; Rats, Inbred Lew; Ribonucleases; RNA, Messenger; Survival Rate; Transcription Factors; Transforming Growth Factor beta

We earlier described a model of fulminant hepatic failure (FHF) in the rat where partial hepatectomy is combined with induction of right liver lobes necrosis. After this procedure, lack of regenerative response in the residual viable liver tissue (omental lobes) was associated with elevated plasma hepatocyte growth factor (HGF) and transforming growth factor beta (TGF-beta1) levels and delayed expression of HGF and c-met mRNA in the remnant liver. Here, we investigated whether syngeneic isolated hepatocytes transplanted in the spleen will prolong survival and facilitate liver regeneration in FHF rats. Inbred male Lewis rats were used. Group I rats (n = 46) received intrasplenic injection of 2 x 10(7) hepatocytes and 2 days later FHF was induced. Group II FHF rats (n = 46) received intrasplenic injection of saline. Rats undergoing partial hepatectomy of 68% (PH; n = 30) and a sham operation (SO; n = 30) served as controls. In 20 FHF rats (10 rats/group), survival time was determined. The remaining 72 FHF rats (36 rats/group) were used for physiologic studies (liver function and regeneration and plasma growth factor levels). In Group I rats survival was longer than that of Group II controls (73 +/- 22 hr vs. 33 +/- 9 hr; P < 0. 01). During the first 36 hr, Group I rats had lower blood ammonia, lactate, total bilirubin, PT, and PTT values, lower activity of liver enzymes, and higher monoethylglycinexylidide (MEGX) production than Group II rats. In Group I rats, livers increased in weight at a rate similar to that seen in PH controls and showed distinct mitotic and DNA synthetic activity (incorporation of bromodeoxyuridine and proliferation cell nuclear antigen expression). Plasma HGF and TGF-beta1 levels in these rats decreased and followed the pattern seen in PH rats; additionally, c-met expression in the remnant liver was accelerated. Hepatocyte transplantation prolonged survival in FHF rats and facilitated liver regeneration. Even though the remnant liver increased in weight four times reaching 30% of the original liver mass, the transplant-bearing rats expired due to inability of the regenerating liver to support the rat.

Topics: Albumins; Ammonia; Animals; Bilirubin; Cell Division; Cell Transplantation; Disease Models, Animal; DNA; Gene Expression Regulation; Hepatic Encephalopathy; Hepatocyte Growth Factor; Lactates; Liver; Liver Regeneration; Male; Mitotic Index; Partial Thromboplastin Time; Proliferating Cell Nuclear Antigen; Prothrombin Time; Proto-Oncogene Proteins c-met; Rats; Rats, Inbred Lew; RNA, Messenger; Spleen; Survival Rate; Transforming Growth Factor beta

Transforming growth factor-beta1 is an important cytokine involved in cell growth and inflammation which has been shown to be inhibitory to hepatic DNA synthesis. The aim of this study was to investigate the plasma levels and hepatic mRNA expression of transforming growth factor-beta1 in patients with fulminant hepatic failure in whom liver regeneration may be impaired.. Plasma levels of transforming growth factor-beta1 and human hepatocyte growth factor were measured in 57 fulminant hepatic failure patients and 20 healthy volunteers by ELISA. Northern blot analysis of transforming growth factor-beta1 and H3 histone, a marker for liver proliferation, was performed in liver tissue of 14 fulminant hepatic failure patients.. The plasma levels of total transforming growth factor-beta1 in fulminant hepatic failure patients on admission (median 38.8 ng/ml, range 8.4-108 ng/ml) were significantly higher than those in control subjects (23.0 ng/ml, 8.5-34.9 ng/ml, p<0.001). Significantly higher levels were observed in non-A, non-B hepatitis patients (57.9 ng/ml, 38.8-108 ng/ml, n=10, p<0.001) compared to patients with paracetamol overdose (37.1 ng/ml, 8.4-72.5 ng/ml, n=47). In contrast, the plasma levels of free transforming growth factor beta1 were greater in paracetamol overdose (623 pg/ml, 46.7-1241 pg/ml, n=21) than in non-A, non-B hepatitis (131 pg/ml, 77.2-254 pg/ml, n=9), with both being higher than control (72.3 pg/ml, 28.7-108, n=7, p<0.001). The plasma levels of human hepatocyte growth factor in patients with paracetamol overdose (7.04 ng/ml, 1.00-62.4 ng/ml) were significantly higher than those in patients with non-A, non-B hepatitis (4.48 ng/ml, 0.74-9.10 ng/ml, p<0.05). Northern blots showed increased mRNA expression of transforming growth factor-beta1 in paracetamol-overdose patients (n=8, p<0.05), but not in patients with non-A non-B hepatitis (n=6), compared to controls (n=4).. The increased circulating plasma TGF-beta1 in FHF may be part of the tissue repair process in fulminant hepatic failure. In patients with non-A, non-B hepatitis, the increased total transforming growth factor-beta1 together with a less elevated hepatocyte growth factor could be related to impaired liver regeneration in this group.

Topics: Acetaminophen; Adolescent; Adult; Aged; Analgesics, Non-Narcotic; Blotting, Northern; Enzyme-Linked Immunosorbent Assay; Female; Hepatic Encephalopathy; Hepatitis, Viral, Human; Hepatocyte Growth Factor; Histones; Humans; Liver; Liver Transplantation; Male; Middle Aged; RNA, Messenger; Transforming Growth Factor beta