Hepatopulmonary syndrome induced by common bile duct ligation in a rabbit model: correlation between pulmonary vascular dilatation on thin-section CT and angiography and serum nitrite concentration or endothelial nitric oxide synthase (eNOS)1 expression

The Effect of Intrahepatic and Intrasplenic Administration of Mesenchymal Stem Cell to Liver Function and Degree of Liver Fibrosis in Common Bile Duct Ligation Model in Rabbit

BACKGROUND

Mesenchymal stem cells (MSC) is a promising alternative method in liver cirrhosis management. Several administration routes of MSC have been studied, but few studies compared one to another. The purpose of this study is to compare the intrahepatic and intrasplenic route of MSC administration in terms of liver function and degree of liver fibrosis in the bile duct ligation model in rabbits.

METHOD

Experimental study was conducted using rabbits (Oryctolagus cuniculus) model undergoing bile duct ligation (BDL). The subjects were randomized into 4 groups: sham surgery; bile duct ligation; bile duct ligation followed by intrahepatic route of MSC (BDL + IH MSC), and bile duct ligation followed by intrasplenic route of MSC (BDL + IS MSC). Umbilical cord mesenchymal stem cell (UC MSC) was administered on the fifth day after bile duct ligation, and the subjects were observed until the fourteenth day after bile duct ligation. The liver function was evaluated with alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total and direct bilirubin. The degree of fibrosis was evaluated with Laennec score, fibrosis area fraction, the number of viable and necrosis hepatocytes, and the number of hepatic progenitor cells.

RESULT

The subjects were randomized into 4 groups: 2 in sham surgery group, and 7 in each of the following groups: BDL, BDL + IH MSC and BDL + IS MSC groups. The mortality rate in BDL group was 57.1 %, while mortality in BDL + IH MSC and BDL + IS MSC groups were 14.3 % and 28.6 % respectively. No significant difference was found regarding liver function in each group, such as AST, ALT, total, and direct bilirubin. Histopathology examination in almost every subject undergone bile duct ligation (regardless of MSC administration) showed degree of fibrosis of Laennec 4B. Fibrosis area fraction, the number of viable and necrotic hepatocytes, and progenitor cells were analyzed; no significant difference was found between BDL + IH MSC and BDL + IS MSC groups, but the groups administered with MSC showed a larger number of viable hepatocytes compared to BDL group. No difference was found between BDL + IH MSC and BDL + IS MSC groups in terms of liver function and histologic parameters.

CONCLUSION

Administration of MSC increases the number of viable hepatocytes, but no difference was found in terms of liver function and degree of liver fibrosis between the intrahepatic route and intrasplenic route of administration.

TYPE OF STUDY

Animal Research, Randomized Controlled Study.

LEVEL OF EVIDENCE

Level I? (animal research is not indicated in the levels of evidence table in the journal website).

A Simple and Easily Reproducible Model of Reversible Obstructive Jaundice in Rats

BACKGROUND/AIM

Cholangiocarcinoma and pancreatic carcinoma are major malignancies that cause obstructive jaundice (OJ). This study aimed to develop a simple and easily reproducible rat model of reversible OJ (ROJ).

MATERIALS AND METHODS

OJ was induced by clamping the common bile duct (CBD) using a U-shaped titanium hemoclip and its base was attached by ligation using 2-cm long 4-0 polypropylene suture. An anti-adhesive sheet was placed around the CBD. OJ was mitigated by pulling the suture to remove the clip under laparotomy 3 days later. Serum chemistry and liver histopathology were compared between the ROJ group and sham surgery (SH) groups.

RESULTS

Three days after inducing OJ, serum total bilirubin, aspartate aminotransferase, and alanine aminotransferase were remarkably elevated in the ROJ group and thereafter reduced significantly after mitigating OJ. Similar findings were confirmed by histopathology.

CONCLUSION

Our rat model of reversible OJ was considered simple and easily reproducible.

Hepatopulmonary syndrome

The hepatopulmonary syndrome (HPS) is a pulmonary complication of cirrhosis and/or portal hypertension whereby patients develop hypoxemia as a result of alterations in pulmonary microvascular tone and architecture. HPS occurs in up to 30% of patients with cirrhosis. Although the degree of hypoxemia does not reliably correlate with the severity of liver disease, patients with HPS have a higher mortality than do patients with cirrhosis without the disorder. There has been progress into defining the mechanisms that lead to hypoxemia in HPS, but to date there are no therapeutic options for HPS aside from liver transplantation.

Hepatopulmonary syndrome

PURPOSE OF REVIEW

To discuss the advances in the understanding of the pathophysiology of experimental and human hepatopulmonary syndrome (HPS) and in the management of HPS, particularly regarding liver transplantation.

RECENT FINDINGS

Advances have been made in defining the pathophysiology of HPS in experimental models as well as in human disease, including the role of endothelin-1, pulmonary monocytes, and angiogenesis. Additionally, the implications of the presence of HPS as it relates to prioritizing patients for liver transplantation and posttransplant outcomes will also be reviewed.

SUMMARY

Mechanisms of disease continue to be defined in HPS, providing potential targets for pharmacologic intervention. Outcomes after liver transplantation are also becoming clearer, including the management of HPS with severe hypoxemia.

The effects of flavanoid on the treatment of hepatopulmonary syndrome

Purpose

Hepatopulmonary syndrome is an arterial oxygenation disorder brought about by advanced liver failure and pulmonary vascular dilatations. The reason why hypoxia develops in hepatopulmonary syndrome depends on the broadening of perialveolar capillary veins. Our study aims to investigate the effects of Flavanoid on hepatopulmonary syndrome through its inhibition of nitric oxide.

Methods

Three groups, each having 8 rats, were formed within the scope of our study. Group I (the control group) only received laparatomy, group II received choledoch ligation, and group III was administered Flavanoid (90% flavonoid diosmin, 10% flavonoid hesperidin) following choledoch ligation. The rats were administered Flavanoid at week two following choledoch ligation. The rats' livers and lungs were examined histopathologically following a five-week follow-up and the perialveolar vein diameters were measured. Arterial blood gases and biochemical parameters were evaluated.

Results

It was seen that fibrosis and oxidative damage in the liver with obstructive jaundice as well as hypoxia with pulmonary perialveolar vein sizes were significantly lower than the other group with cirrhosis formed through the administration of Flavanoid.

Conclusion

We have concluded that Flavanoid administration might be useful in the treatment of hypoxia in hepatopulmonary syndrome and the delay of cirrhosis contraction.

Reversible surgical model of biliary inflammation and obstructive jaundice in mice

Common bile duct (CBD) ligation is used in animal models to induce biliary inflammation, fibrosis, and cholestatic liver injury, but results in a high early postoperative mortality rate, probably from traumatic pancreatitis. We modified the CBD ligation model in mice by placing a small metal clip across the lower end of the CBD. To reverse biliary obstruction, a suture was incorporated within the clip during its placement. The suture and clip were removed on postoperative d 5 or 10 for biliary decompression. After 5 d of biliary obstruction, the gallbladder showed an 8-fold increase in wall thickness and a 17-fold increase in tissue myeloperoxidase activity. Markedly elevated serum levels of alkaline phosphatase and bilirubin indicated injury to the biliary epithelium and hepatocytes. Early postoperative (d 0-2) survival was 100% and later (d 3-5) survival was 85% (n=54 mice). We successfully reversed biliary obstruction in 20 mice (37%). Overall survival after reversal was 70%. In surviving mice, biliary decompression was complete, inflammation was reduced, and jaundice resolved. Histologic features confirmed reduced epithelial damage, edema, and neutrophil infiltration. Our technique minimized postoperative death, maintained an effective inflammatory response, and was easily reversible without requiring repeat laparotomy. This reversible model can be used to further define molecular mechanisms of biliary inflammation, fibrosis, and liver injury in genetically altered mice.

Mcp-1, eNOS, tPA and PAI-1 gene polymorphism and correlation of genotypes and phenotypes in hepatopulmonary syndrome

AIM

The aim of this case-control study was to investigate both the distribution of MCP-1, eNOS, tPA and PAI-1 gene polymorphism and correlation of genotypes and phenotypes.

METHOD

Between September 1997-January 2005, 20 patients with HPS (group 1) were compared with a group of cirrhotic patients (group 2, n = 19) as well as unrelated healthy controls (group 3, n = 59) in respect to MCP1, eNOS, tPA and PAI-1 gene polymorphism frequency distribution.

RESULTS

MCP1-2518G allele carriage in patients with HPS was higher than in controls (P = 0.01). In non-HPS cirrhotic patients, eNOS Glu298Asp, Asp gene carriers and frequency of Asp alleles were detected to be considerably higher than in patients with HPS and healthy controls (P < 0.05).

CONCLUSION

HPS is more common in patients with MCP-1 2518G gene carriage; conversely it is less frequent in patients with high frequency of eNOS 298Asp allele and eNOS 298Asp carriage.