Liver cell injury and fibrosis

Azoospermia and multi-organ damage in juvenile rats exposed to α-Terpineol from weaning to sexual maturity

This study aimed to evaluate the repeated oral administration of α-terpineol in juvenile Wistar rats over a 70-day period. The objective was to assess the potential systemic and reproductive toxicity of α-terpineol when administered by gavage at doses of 75, 150, and 300 mg/kg/day to juvenile Wistar rats for 70 days from postnatal day 24. The control group received corn oil for 70 days. During the study, various parameters were evaluated, including clinical signs, body weight, food intake, neurobehavioral observations, haematology, serum biochemistry, organ weights, steroidogenic gene expression, and histopathological examination. No toxicity-related changes were observed in body weight, food intake, neurobehavioral observations, or steroidogenic gene expression. However, sperm evaluation revealed a complete absence of sperm and delayed sexual maturation. Total cholesterol was significantly elevated in both sexes, and serum testosterone was reduced at the 150 and 300 mg/kg doses. Microscopic examination showed severe pathological changes in the testes, epididymis, liver, and kidneys of both males and females. After the 14-day recovery period, total cholesterol levels returned to the normal range, but no recovery was observed in the other organs. The no-observed-adverse-effect level was 75 mg/kg/day for male rats based on the histopathological findings in the testes, liver, and kidneys, and for female rats based on the kidney and liver histopathology.

Periportal thickening on magnetic resonance imaging for hepatic fibrosis in infantile cholestasis

BACKGROUND

Untreated neonatal cholestasis can progress to liver cirrhosis and end stage liver disease in infancy due to prolonged hepatocyte and biliary tree injury and may require liver transplantation. Therefore, non-invasive evaluation of hepatic fibrosis is important in infants with cholestasis.

AIM

To investigate the usefulness of periportal thickening (PT) measured on liver magnetic resonance imaging (MRI) for the assessment of hepatic fibrosis in infants with cholestasis including biliary atresia (BA).

METHODS

This retrospective study included infants less than 6 mo who underwent liver MRI and biopsy for the evaluation of infantile cholestasis. PT and spleen size were measured on MRI. Serologic assessment was based on aspartate transaminase to platelet ratio index (APRI). The grade of histopathologic fibrosis was assessed by the METAVIR grading system. Correlation and diagnostic performance of PT, normalized spleen size ratio (SR, using the upper normal size limit), and APRI for diagnosing hepatic fibrosis were obtained by receiver-operating characteristic (ROC) curve analysis.

RESULTS

A total of 155 patients were included, 110 of which were diagnosed with BA. Mean age at the time of MRI was 57.6 ± 34.4 d. There were positive correlations between fibrosis grade and PT and SR, even after adjusting age (all, P < 0.001). For the diagnosis of significant fibrosis (METAVIR grade F2-F4), the area under the ROC curve was 0.899 (95%CI: 0.840–0.941) for PT (cutoff, 4.2 mm), which was higher than 0.741 (95%CI: 0.664–0.808) for SR and 0.712 (95%CI: 0.634–0.782) for APRI (both, P < 0.001). For the diagnosis of cirrhosis (F4), the area under the ROC curve was the highest with SR as 0.790 (95%CI: 0.718–0.852).

CONCLUSION

Liver MRI findings of PT and SR are useful to assess clinically significant hepatic fibrosis (F2 and higher) in infants with cholestasis including BA.

Utility and accuracy of transient elastography in determining liver fibrosis: a case-control study

The objectives of this prospective case-control study were to determine liver stiffness (LSM) by transient elastography (TE) in children with newly diagnosed chronic liver disease (CLD) and to find out normal values in healthy Indian children. Two groups (A: 50 CLD who underwent liver biopsy and B: 50 healthy) aged 5-18 years were recruited prospectively. Liver biopsies were scored as per Metavir scoring and compared with TE. The median age of 100 recruited children was 13.6 years. In group B, normal LSM was 4.9 (2.5-7.3) kPa with significantly higher LSM in adolescent males (5.6 (4.1-7.3) kPa) as compared with females (4.3 (3.7-4.9) kPa), p = 0.001. In group A, TE was excellent in discriminating significant fibrosis (≥ F2) (P = 0.001) at a cut-off value of 10.6 kPa with area under receiver operating characteristic curve of 0.96. Metavir fibrosis stage (β = 0.611; R2 = 0.586) and age (β = 0.230; R2 = 0.586) were independent variables associated with higher LSM in stepwise multiple logistic regression analysis.Conclusions: TE is an excellent non-invasive tool to assess significant liver fibrosis and can be used as an alternative to liver biopsy. Normative value of TE in adolescent males is higher than in females.What is Known:• Transient elastography is a good non-invasive test for liver fibrosis assessment.• Normal liver stiffness depends on race, gender, and age.What is New:• This is the first study from India to show the normative data of transient elastography in healthy Indian children.• We have documented that liver stiffness measurement by fibroscan in treatment naïve chronic liver disease has excellent correlation in significant fibrosis, severe fibrosis, and cirrhosis.

Normal values of liver elasticity measured by real-time tissue elastography (RTE) in healthy infants and children

PURPOSE

To define normal values of liver elasticity measured by real-time tissue elastography (RTE) in healthy infants and children.

METHODS

RTE was performed on 91 children and adolescents by two experienced observers (female, n = 43; male, n = 48) and in two age groups (0-10 years, n = 45; 11-20 years, n = 46). Hepatopathies were excluded clinically by extensive laboratory testing and by ultrasound. RTE provides a histogram from a region of interest (ROI) in the liver representing the degree of stiffness of the liver. The distribution of the colors in the histogram corresponds to organ elasticity. By calculating the mean of stiffness values, a numerical value is expressed in arbitrary units (a.u.) representing the mean elasticity of the liver (MEAN). Additionally, the percentage values of relatively stiffer areas (color coded in blue) in the ROI can be calculated (%AREA). A Mann-Whitney U test was performed for these two parameters according to gender. The reproducibility of these values was determined with an intraclass correlation coefficient (ICC) test on another group of 18 healthy volunteers.

RESULTS

The median elasticity was 106 a.u. Gender did not have an influence on the parameters (MEAN: p = 0.052; %AREA: p = 0.051). Age-specific analyses did not yield any significant difference between the two age groups for either of the two analyzed parameters (MEAN: p = 0.059; %AREA: p = 0.058). The ICC test demonstrated a moderate agreement for MEAN (ICC = 0.582) and %AREA (ICC = 0.659).

CONCLUSION

Real-time elastography is a new sonography-based method and may be used as a supportive analysis to assess liver parenchyma elasticity in children, especially when fibrosis is suspected. We measured RTE normal values in children as reference data.

The modulation of hepatic adenosine triphosphate and inflammation by eicosapentaenoic acid during severe fibrotic progression in the SHRSP5/Dmcr rat model

AIMS

Eicosapentaenoic acid (EPA) can ameliorate certain liver lesions involved in non-alcoholic steatohepatitis (NASH). A previous study has found that stroke-prone spontaneously hypertensive 5/Dmcr (SHRSP5/Dmcr) rats fed a high fat-cholesterol (HFC) diet developed fibrotic steatohepatitis with histological similarities to NASH. This study evaluated the potential effects and mechanisms of action of EPA supplementation using this rodent model.

MAIN METHODS

Male rats were randomly assigned to groups that were fed with either the stroke-prone (SP) diet or HFC diet with or without EPA for 2, 8 and 14 weeks, respectively. The liver histopathology, biochemical features, mRNA and protein levels, and nuclear factor-κB (NF-κB) DNA binding activity were determined.

KEY FINDINGS

The SP diet-fed rats presented normal livers. Conversely, the HFC diet-fed rats developed microvesicular/macrovesicular steatosis, inflammation, ballooning degeneration and severe fibrosis. At 2 weeks, the administration of EPA inhibited hepatic inflammatory recruitment by blocking the phosphorylation of inhibitor of κB-α (IκBα), which antagonizes the NF-κB activation pathway. The dietary supplementation of EPA for 8 weeks ameliorated hepatic triglyceride accumulation and macrovesicular steatosis by inhibiting the HFC diet-induced decrease in the protein levels of enzymes involved in fatty acid β-oxidation including carnitine palmitoyltransferase 1, very long chain acyl-CoA dehydrogenase and peroxisomal bifunctional protein. Although the administration of EPA elicited no histologically detectable effects on severe fibrosis at 14 weeks, it restored an HFC diet-induced decline in hepatic adenosine triphosphate (ATP) levels and suppressed ballooning degeneration, suggesting that EPA may inhibit HFC diet-induced ATP loss and cell death.

SIGNIFICANCE

Initial amelioration of the inflammation and steatosis in the rats after EPA supplementation indicates a possibility to treat steatohepatitis. Additionally, this study provides new insights into the roles of EPA in hepatic ATP depletion and subsequent hepatocellular injury during severe fibrosis.

Feasibility study and control values of transient elastography in healthy children

Transient elastography (TE) is a new technique for the non-invasive assessment of liver fibrosis. The degree of fibrosis is equivalent to the liver stiffness measured in kilopascal (kPa). It is frequently used in adult patients with a mean normal stiffness of 4.4-5.5 kPa. Since 2008, liver stiffness can be measured even in small children and infants following the availability of a new probe with a smaller diameter (S-probe 5 mm) than the regular probe (M-probe 7 mm). We report control values for healthy children between 0 and 18 years and investigated the feasibility of this technique in a pediatric population. For control values, TE was performed in infants and children after exclusion of liver disease by medical history, clinical examination, blood investigation, and abdominal ultrasound. For feasibility analyses the results of all TE performed in our clinic were analyzed irrespective of the underlying disease. Liver stiffness was measured with the S-probe (thorax diameter <45 cm (S1) or 45-75 cm (S2)) and the M-probe (thorax diameter >75 cm) according to the manufacturer's recommendations. A total of 240 healthy children were analyzed to establish control values. The median liver stiffness was 4.7 kPa resulting in an upper limit of normal of 6.47 kPa. Median values of stiffness were significantly age dependent with 4.40, 4.73, and 5.1 kPa in children 0-5, 6-11, and 12-18 years (p = 0.001) while the interquartile range decreased with age (0.8, 0.7, and 0.6 kPa). The resulting upper limit of normal (median plus 1.64 times standard deviation) was 5.96, 6.65, and 6.82 kPa. Girls between 11 and 18 years showed a significantly lower median stiffness than boys of the same age (4.7 vs. 5.6 kPa; p < 0.005). Feasibility was tested in 975 consecutive liver stiffness measurements (LSM) in children 0-18 years of age. Patients with invalid LSM were significantly younger than those with valid LSM (5.8 vs. 9.7 years, p < 0.0001), showed a significantly higher stiffness (10.2 vs. 6.17, p < 0.0001), and examinations took significantly longer (202 vs. 160 s, p < 0.0001). TE is technically possible in children of all age groups. The upper limit of normal increases significantly with age. Due to movement artifacts the measurement is reliable from the age of 6 without sedation. In younger children the number of invalid measurements increases significantly. Further studies are needed to asses the value of TE in the diagnosis and follow-up of liver disease in pediatric hepatology.

Feasibility study and control values of transient elastography in healthy children

Transient elastography (TE) is a new technique for the non-invasive assessment of liver fibrosis. The degree of fibrosis is equivalent to the liver stiffness measured in kilopascal (kPa). It is frequently used in adult patients with a mean normal stiffness of 4.4-5.5 kPa. Since 2008, liver stiffness can be measured even in small children and infants following the availability of a new probe with a smaller diameter (S-probe 5 mm) than the regular probe (M-probe 7 mm). We report control values for healthy children between 0 and 18 years and investigated the feasibility of this technique in a pediatric population. For control values, TE was performed in infants and children after exclusion of liver disease by medical history, clinical examination, blood investigation, and abdominal ultrasound. For feasibility analyses the results of all TE performed in our clinic were analyzed irrespective of the underlying disease. Liver stiffness was measured with the S-probe (thorax diameter <45 cm (S1) or 45-75 cm (S2)) and the M-probe (thorax diameter >75 cm) according to the manufacturer's recommendations. A total of 240 healthy children were analyzed to establish control values. The median liver stiffness was 4.7 kPa resulting in an upper limit of normal of 6.47 kPa. Median values of stiffness were significantly age dependent with 4.40, 4.73, and 5.1 kPa in children 0-5, 6-11, and 12-18 years (p = 0.001) while the interquartile range decreased with age (0.8, 0.7, and 0.6 kPa). The resulting upper limit of normal (median plus 1.64 times standard deviation) was 5.96, 6.65, and 6.82 kPa. Girls between 11 and 18 years showed a significantly lower median stiffness than boys of the same age (4.7 vs. 5.6 kPa; p < 0.005). Feasibility was tested in 975 consecutive liver stiffness measurements (LSM) in children 0-18 years of age. Patients with invalid LSM were significantly younger than those with valid LSM (5.8 vs. 9.7 years, p < 0.0001), showed a significantly higher stiffness (10.2 vs. 6.17, p < 0.0001), and examinations took significantly longer (202 vs. 160 s, p < 0.0001). TE is technically possible in children of all age groups. The upper limit of normal increases significantly with age. Due to movement artifacts the measurement is reliable from the age of 6 without sedation. In younger children the number of invalid measurements increases significantly. Further studies are needed to asses the value of TE in the diagnosis and follow-up of liver disease in pediatric hepatology.

Potent antioxidant role of pirfenidone in experimental cirrhosis

Three important features must be considered when proposing therapeutic strategies in liver cirrhosis: inflammation, oxidative stress and fibrogenesis. Pirfenidone is a synthetic molecule which oxidative action has not been tested in cirrhosis. Cirrhosis was induced in rats by ligation of the common bile duct or carbon tetrachloride (CCl(4)) chronic intoxication and treated with pirfenidone or diphenyleneiodonium (a potent known antioxidant) for the last two weeks for bile duct ligation model or for the last three weeks for CCl(4) chronic intoxication. A 60% reduction in fibrosis index for bile duct ligation model and 42% for CCl(4) along with reduced inflammation was observed. Considerable reduction on hepatic enzymes and total and direct bilirubins were detected with pirfenidone in both models. Pirfenidone antioxidant capacity rendered a 28% and 30% reduction in nitrites and malonyldealdehide concentration in bile duct ligation and 52% and 38% in CCl(4). With respect to gene expression, fibrotic genes like transforming growth factor-beta (TGF-beta) and collagen Ialpha (Col-1alpha) were down-regulated by pirfenidone and increased expression of regenerative genes like hepatocyte growth factor (HGF) and c-met . Superoxide dismutase (SOD), catalase (CAT) and inducible nitric oxide synthase (iNOS) gene expression were importantly down-regulated where nuclear factor kappa B (NF-kappaB) binding activity also decreased with pirfenidone treatment. Also, SOD and CAT functional activity decreased after pirfenidone action. On the other hand, diphenyleneiodonium induced a drop in oxidative stress similar in extent to pirfenidone, but it was not as effective as pirfenidone in reducing fibrosis. In this work, we showed antioxidant properties of pirfenidone beyond its well-known antifibrotic effect. These features make pirfenidone an attractive drug for trying fibrotic diseases accompanied by oxidative stress processes.

Alpha-fetoprotein and other tumour-associated antigens for immunotherapy of hepatocellular cancer

BACKGROUND

Hepatocellular carcinoma (HCC) is a leading cause of cancer death, with few treatment options for advanced disease.

OBJECTIVES

Here, we review the aetiology of HCC and focus on recent data on tumour-associated antigens (TAA) for HCC, their functions and potential use as immunological targets for immune-based therapy for HCC. In addition, we examine some aspects of antigen presentation within the liver.

RESULTS/CONCLUSIONS

alpha-Fetoprotein (AFP) has been investigated for many years as a TAA, and has been tested in recent clinical trials. More recently, additional TAA have been identified and new therapeutic approaches have been investigated which may be testable clinically in this difficult disease setting.

Experimental poisoning by Senecio brasiliensis in calves: quantitative and semi-quantitative study on changes in the hepatic extracellular matrix and sinusoidal cells

Extracellular matrix plays an important role in chronic hepatic lesions and has been studied in experimental intoxication models. However in cattle, studies on chronic disease have focused on the hepatocellular damage and extracellular matrix (ECM) changes are usually overlooked. There are no specific studies on the hepatic ECM in either normal or chronically damaged bovine liver. Thus an experimental model of hepatic toxicity model using Senecio brasiliensis poisoned calves was designed. Senecio brasiliensis contains pyrrolizidine alkaloids which cause either acute or chronic progressive dose dependent liver damage. Five calves were orally fed with 0.38g of dry leaves of S. brasiliensis/kg/day for 24 days. Liver needle biopsy specimens were obtained every 15 days for 60 days. Clinical signs of digestive complications appeared at 3rd week. One calf died on 45th day and four were evaluated up to 60th day. Biopsy samples were processed for routine light microscopy, immuno-histochemistry and transmission electron microscopy. From 30th day on progressive liver damage characterized by hepatocellular ballooning, necrosis, apoptosis and megalocytosis, centrilobular, pericellular and portal fibrosis were seen by light microscopy. Quantitative and semi-quantitative measurements of hepatic ECM components were performed before and after the onset of lesions. Morphometric analysis of total collagen and elastic fiber system was conducted. Total collagen and I and III collagen types progressively increased in throughout the liver of affected calves. Changes in location, amount and disposition of the elastic fiber system were also observed. Then numbers of Kupffer cells were significantly increased at 30th day and total numbers of sinusoidal cells were significantly increased at 45th and 60th days. Liver damage was progressive and irreversible even after the exposure to the plant was discontinued. Severe fibrotic lesions occurred mainly in portal tracts, followed by veno-occlusive and pericellular fibrosis. Collagen types I and III s were present in every normal and damaged liver, with predominance of type I. In affected calves the increase of total collagen and elastic fibers system paralleled the number of total sinusoidal cells.

Contribution of non-parenchymal cells to the performance of micropatterned hepatocytes

Hepatocytes within current bioartificial liver designs are unable to maintain the wide range of differentiated functions observed for the liver in vivo. As recent studies suggest, the absence of controlled interactions between hepatocytes and non-parenchymal cell populations of the liver may contribute to this hepatocyte dedifferentiation. The current study investigates the effect of Kupffer cells, fibroblasts, and human umbilical vein endothelial cells on hepatocyte function. To effectively study the effect of these heterotypic cell-to-cell interactions, it is necessary to establish a culture environment that controls the interactions between multiple cell types. Micropatterning is such a technique and was used in the current study. In addition, to elucidate the influence of soluble factors on hepatocyte function, the micropatterned results were compared with those of the trans-well culture system. Specifically, we compared the morphological and functional changes of hepatocytes cultured with these cells at varying ratios. Our results suggest that direct heterotypic cell-to-cell contact between hepatocytes and fibroblasts, and soluble factor exchanges between hepatocytes and human umbilical vein endothelial cells, significantly enhanced hepatocyte performance.

A study of unfractionated and low molecular weight heparins in a model of cholestatic liver injury in the rat

Forty-eight rats with biliary obstruction induced by double ligation and section of the common bile duct were randomly and blindly assigned to receive subcutaneous injection of either conventional heparin sodium (1000IU kg(-1)), three already marketed low molecular weight heparin (LMWH) preparations: nadroparin (1000 anti-Xa IU kg(-1)), tinzaparin (1000 anti-Xa IU kg(-1)), enoxaparin (180 anti-Xa IU kg(-1)) or saline. Drugs were administered once a day, starting 7 days after surgery and continued for 3 weeks. At the end of the treatment period, rats were killed and analyzed for blood biochemistry and liver pathology. Liver fibrosis was assessed by image analysis. Data indicated that treatment with nadroparin decreased plasma total bilirubin, serum alkaline phosphatase (ALP) and gamma glutamyltransferase (GGT) levels by 80.3, 70.7 and 42%, compared with bile duct ligated (BDL) control values. The reduction in plasma total protein observed in BDL controls was prevented by nadroparin. Enoxaparin-treated rats showed significant reduction in plasma total bilirubin and alanine aminotransferase levels by 32.5 and 38.4% versus BDL controls. Liver necrosis evaluated histologically was significantly reduced in the nadroparin- and enoxaparin-treated rats. Morphometric analysis showed significant reduction in fibrosis on nadroparin and enoxaparin treatment: area of fibrosis: 1.66 +/- 0.17% and 14.03 +/- 1.1% versus 18.94 +/- 2.4% (P<0.05); nadroparin and enoxaparin versus BDL control. By contrast, neither conventional heparin nor tinzaparin prevented the bile duct ligation-induced liver damage as indicated by increased plasma aminotransferases, ALP and GGT concentrations and the histological evidence of necrosis. Total serum bilirubin was increased by 27.5% in rats treated with conventional heparin, while ALP and GGT levels were 38.6 and 31.4% higher after tinzaparin treatment versus BDL controls. Significant increase in the area of fibrosis was observed after tinzaparin treatment compared to BDL control group. Results suggest a beneficial effect for nadroparin and enoxaparin in the therapy of patients with obstructive jaundice or cholestatic liver disorders. The present data from bile duct ligated rats suggest an antifibrotic effect for nadroparin and enoxaparin.