Non-alcoholic fatty liver disease (NAFLD) is one of the leading cause of hepatocellular carcinoma (HCC). This association is supported by the translocation of bacteria products into the portal ...system, which acts on the liver through the gut-liver axis. We hypothesize that portosystemic shunting can disrupt this relationship, and prevent NAFLD-associated HCC.
HCC carcinogenesis was tested in C57BL/6 mice fed a high-fat high-sucrose diet (HFD) and injected with diethylnitrosamine (DEN) at two weeks of age, and in double transgenic LAP-tTA and TRE-MYC (LAP-Myc) mice fed a methionine-choline-deficient diet. Portosystemic shunts were established by transposing the spleen to the sub-cutaneous tissue at eight weeks of age.
Spleen transposition led to a consistent deviation of part of the portal flow and a significant decrease in portal pressure. It was associated with a decrease in the number of HCC in both models. This effect was supported by the presence of less severe liver steatosis after 40 weeks, and lower expression levels of liver fatty acid synthase. Also, shunted mice exhibited lower liver oxygen levels, a key factor in preventing HCC as confirmed by the development of less HCCs in mice with hepatic artery ligation.
The present data show that portosystemic shunting prevents NAFLD-associated HCC, utilizing two independent mouse models. This effect is supported by the development of less steatosis, and a restored liver oxygen level. Portal pressure modulation and shunting deserve further exploration as potential prevention/treatment options for NAFLD and HCC.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Nonalcoholic steatohepatitis (NASH) can lead to hepatocellular carcinoma (HCC). Although immunotherapy is used as first-line treatment for advanced HCC, the impact of NASH on anticancer immunity is ...only partially characterized. We assessed the tumor-specific T cell immune response in the context of NASH. In a mouse model of NASH, we observed an expansion of the CD44
+
CXCR6
+
PD-1
+
CD8
+
T cells in the liver. After intra-hepatic injection of RIL-175-LV-OVA-GFP HCC cells, NASH mice had a higher percentage of peripheral OVA-specific CD8
+
T cells than control mice, but these cells did not prevent HCC growth. In the tumor, the expression of PD-1 on OVA-specific CD44
+
CXCR6
+
CD8
+
cells was higher in NASH mice suggesting lowered immune activity. Treating mice with an anti-CD122 antibody, which reduced the number of CXCR6
+
PD-1
+
cells, we restored OVA-specific CD8 activity, and reduced HCC growth compared to untreated NASH mice. Human dataset confirmed that NASH-affected livers, NASH tissues adjacent to HCC and HCC in patients with NASH exhibited gene expression patterns supporting mouse observations. Our findings demonstrate the immune system fails to prevent HCC growth in NASH, primarily linked to a higher representation of CD44
+
CXCR6
+
PD-1
+
CD8
+
T cells. Treatment with an anti-CD122 antibody reduces the number of these cells and prevents HCC growth.
Hypothermic and normothermic ex vivo liver perfusions promote organ recovery after donation after circulatory death (DCD). We tested whether these perfusions can reduce the risk of hepatocellular ...carcinoma (HCC) recurrence in a 1h-DCD syngeneic transplantation model, using Fischer F344 rats. DCD grafts were machine perfused for 2h with hypothermic perfusion (HOPE) or normothermic perfusion (NORMO), and transplanted. After reperfusion, we injected HCC cells into the vena porta. On day 28 after transplantation, we assessed tumour volumes by MRI. Control rats included transplantations with Fresh and non-perfused DCD livers. We observed apoptotic-necrotic hepatocyte foci in all DCD grafts, which were more visible than in the Fresh liver grafts. Normothermic perfusion allowed a faster post-transplant recovery, with lower day 1 levels of transaminases compared with the other DCD. Overall, survival was similar in all four groups and all animals developed HCCs. Total tumor volume was lower in the Fresh liver recipients compared to the DCD and DCD+HOPE recipients. Volumes in DCD+NORMO recipients were not significantly different from those in the Fresh group. This experiment confirms that ischemia/reperfusion injury promotes HCC cell engraftment/growth after DCD liver transplantation. Using the present extreme 1h ischemia model, both hypothermic and normothermic perfusions were not effective in reducing this risk.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Because of the wide availability of genetically modified animals, mouse orthotopic liver transplantation is often preferred over rat liver transplantation. We present a simplified mouse liver ...transplantation technique and compare transplantation outcomes with versus without hepatic artery anastomosis. Instruments for liver implantation were designed and printed with a 3‐dimensional (3D) printer. The suprahepatic vena cava anastomosis was performed with a 10‐0 running suture. The vena porta and infrahepatic vena cava were joined on extraluminal cuffs, using the 3D‐printed device for spatial alignment and stabilization. The hepatic artery was reconstructed in half of the recipients using intraluminal stents. Liver function tests (3, 7, and 28 days) and histology (7 and 28 days) were assessed after transplantation. We performed 22 consecutive syngeneic C57BL/6 mouse orthotopic liver transplantations. The median portal clamping time was 12.5 ± 1.5 minutes. The survival rate at 4 weeks was 100% for both arterialized and nonarterialized recipients (n = 7, 4 recipients of each group being killed for early histology at day 7). Liver function tests at 3, 7, and 28 days were similar between arterialized versus nonarterialized groups. Liver parenchyma demonstrated only irrelevant abnormalities in both groups. The proposed device allows for a shorter clamping time compared with the published literature. Using this technique, the artery does not need to be anastomosed, with no impact on graft and recipient outcomes. The device is available for 3D printing. Liver Transplantation 22 1688–1696 2016 AASLD.
Emerging evidence suggests that maternal obesity negatively impacts the health of offspring. Additionally, obesity is a risk factor for hepatocellular carcinoma (HCC). Our study aims to investigate ...the impact of maternal obesity on the risk for HCC development in offspring and elucidate the underlying transmission mechanisms.
Female mice were fed either a high-fat diet (HFD) or a normal diet (ND). All offspring received a ND after weaning. We studied liver histology and tumor load in a N-diethylnitrosamine (DEN)-induced HCC mouse model.
Maternal obesity induced a distinguishable shift in gut microbial composition. At 40 weeks, female offspring of HFD-fed mothers (HFD offspring) were more likely to develop steatosis (9.43% vs. 3.09%, p = 0.0023) and fibrosis (3.75% vs. 2.70%, p = 0.039), as well as exhibiting an increased number of inflammatory infiltrates (4.8 vs. 1.0, p = 0.018) and higher expression of genes involved in fibrosis and inflammation, compared to offspring of ND-fed mothers (ND offspring). A higher proportion of HFD offspring developed liver tumors after DEN induction (79.8% vs. 37.5%, p = 0.0084) with a higher mean tumor volume (234 vs. 3 μm3, p = 0.0041). HFD offspring had a significantly less diverse microbiota than ND offspring (Shannon index 2.56 vs. 2.92, p = 0.0089), which was rescued through co-housing. In the principal component analysis, the microbiota profile of co-housed animals clustered together, regardless of maternal diet. Co-housing of HFD offspring with ND offspring normalized their tumor load.
Maternal obesity increases female offspring’s susceptibility to HCC. The transmission of an altered gut microbiome plays an important role in this predisposition.
The worldwide incidence of obesity is constantly rising, with more and more children born to obese mothers. In this study, we investigate the impact of maternal diet on gut microbiome composition and its role in liver cancer development in offspring. We found that mice born to mothers with a high-fat diet inherited a less diverse gut microbiome, presented chronic liver injury and an increased risk of developing liver cancer. Co-housing offspring from normal diet- and high-fat diet-fed mothers restored the gut microbiome and, remarkably, normalized the risk of developing liver cancer. The implementation of microbial screening and restoration of microbial diversity holds promise in helping to identify and treat individuals at risk to prevent harm for future generations.
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•Obese mothers transmit an altered microbiome to their offspring which persists until adulthood.•Maternal obesity increased steatosis, fibrosis and liver inflammation in offspring.•Offspring of obese mothers are at a higher risk of developing liver cancer.•Co-housing offspring of obese and lean mothers restores the gut microbiome and normalizes the liver cancer risk.•Abundance of Erysipelotrichaceae and Lachnospiraceae bacteria correlate with tumor load, Akkermansiaceae with liver inflammation.
The global obesity epidemic particularly affects women of reproductive age. Offspring of obese mothers suffer from an increased risk of liver disease but the molecular mechanisms involved remain ...unknown. We performed an integrative genomic analysis of datasets that investigated the impact of maternal obesity on the hepatic gene expression profile of the offspring in mice. Furthermore, we developed a murine model of maternal obesity and studied the development of liver disease and the gene expression profile of the top dysregulated genes by quantitative real-time polymerase chain reaction (qPCR). Our data are available for interactive exploration on our companion webpage. We identified five publicly available datasets relevant to our research question. Pathways involved in metabolism, the innate immune system, the clotting cascade, and the cell cycle were consistently dysregulated in the offspring of obese mothers. Concerning genes involved in the development of liver disease,
,
and six other genes were dysregulated in multiple independent datasets. In our own model, we observed a higher tendency towards the development of non-alcoholic liver disease (60 vs. 20%) and higher levels of alanine aminotransferase (41.0 vs. 12.5 IU/l,
= 0.008) in female offspring of obese mothers. Male offspring presented higher levels of liver fibrosis (2.4 vs. 0.6% relative surface area,
= 0.045). In a qPCR gene expression analysis of our own samples, we found
, and
to be dysregulated by maternal obesity. Maternal obesity represents a looming threat to the liver health of future generations. Our comprehensive transcriptomic analysis will help to better understand the mechanisms of the development of liver disease in the offspring of obese mothers and can give rise to further explorations.
Phosphoenolpyruvate carboxykinase 1 (PCK1 or PEPCK-C) is a cytosolic enzyme converting oxaloacetate to phosphoenolpyruvate, with a potential role in gluconeogenesis, ammoniagenesis, and cataplerosis ...in the liver. Kidney proximal tubule cells display high expression of this enzyme, whose importance is currently not well defined. We generated PCK1 kidney-specific knockout and knockin mice under the tubular cell-specific PAX8 promoter. We studied the effect of PCK1 deletion and overexpression at the renal level on tubular physiology under normal conditions and during metabolic acidosis and proteinuric renal disease. PCK1 deletion led to hyperchloremic metabolic acidosis characterized by reduced but not abolished ammoniagenesis. PCK1 deletion also resulted in glycosuria, lactaturia, and altered systemic glucose and lactate metabolism at baseline and during metabolic acidosis. Metabolic acidosis resulted in kidney injury in PCK1-deficient animals with decreased creatinine clearance and albuminuria. PCK1 further regulated energy production by the proximal tubule, and PCK1 deletion decreased ATP generation. In proteinuric chronic kidney disease, mitigation of PCK1 downregulation led to better renal function preservation. PCK1 is essential for kidney tubular cell acid-base control, mitochondrial function, and glucose/lactate homeostasis. Loss of PCK1 increases tubular injury during acidosis. Mitigating kidney tubular PCK1 downregulation during proteinuric renal disease improves renal function.
Phosphoenolpyruvate carboxykinase 1 (PCK1) is highly expressed in the proximal tubule. We show here that this enzyme is crucial for the maintenance of normal tubular physiology, lactate, and glucose homeostasis. PCK1 is a regulator of acid-base balance and ammoniagenesis. Preventing PCK1 downregulation during renal injury improves renal function, rendering it an important target during renal disease.
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