Paediatric cholestatic liver disease: Diagnosis, assessment of disease progression and mechanisms of fibrogenesis

Efficacy and Safety of Ileal Bile Acid Transport Inhibitors in Inherited Cholestatic Liver Disorders: A Meta-analysis of Randomized Controlled Trials

Background

Inherited cholestatic liver disorders such as progressive familial intrahepatic cholestasis (PFIC) and Alagille syndrome result in significant pruritus and increased serum bile acids, necessitating liver transplantation. This study aims to evaluate the efficacy and safety of Ileal bile acid transport inhibitors (IBATIs) in children with PFIC and Alagille syndrome.

Methods

We conducted a comprehensive search across the databases to identify relevant randomized controlled trials (RCTs), and Covidence was used to screen eligible articles. All outcomes data were synthesized using risk ratios (RRs) or mean differences (MDs) with 95% confidence intervals (CIs) in RevMan 5.4. PROSPERO: CRD42024564270.

Results

Four multicenter RCTs involving 215 patients were included. IBATIs were associated with a significant reduction in Itch Observer Reported Outcome (Itch (ObsRo)) score (MD: -0.90, 95% CI [-1.17, -0.63], P < 0.01), serum bile acids (MD: -119.06, 95% CI [-152.37, -85.74], P < 0.01), total bilirubin (MD: -0.73, 95% CI [-1.32, -0.15], P = 0.01), and increased proportion of patients achieving ≥1 score reduction in Itch (ObsRo) score (RR: 2.54, 95% CI [3.83, 1.69], P < 0.01) and bile acid responders (RR: 8.76, 95% CI [2.46, 31.23], P < 0.01) compared with placebo. No differences were observed in any treatment-emergent adverse events (TEAs) (RR: 1.02, 95% CI [1.12, 0.93], P = 0.71), TEAs leading to drug discontinuation (1.03, 95% CI [5.56, 0.19], any serious TEAs, or liver-related TEAs.

Conclusion

IBATIs showed significant improvement in various cholestatic parameters with tolerable safety profile; however, future research on optimal dosage and long-term outcomes is needed.

Evaluation of Hepatic Shear Wave Elastography to Assess Liver Fibrosis in Biliary Atresia Patients and Its Correlation with Liver Histology and Surgical Outcomes: A Prospective Observational Study

Introduction  The native liver survival in biliary atresia (BA) depends on various factors, and one of the crucial factors is the rate of progression of liver fibrosis after portoenterostomy, but there is no reliable investigation to assess it. This study evaluated shear wave elastography (SWE) to detect liver fibrosis in BA patients and assess its utility during follow-up. Materials and Methods  This was an observational study; SWE was done preoperatively and postoperatively at 3 and 6 months. The SWE values were analyzed to determine their correlations with preoperative liver histology as well as with postoperative SWE variation between different postoperative outcomes. Results  Twenty-one patients were included in the study; the preoperative SWE values were strongly correlated with liver biopsy grading ( p  < 0.001). At the 3 months postoperatively, SWE was done for 18 children: 12 in group A (patent bilioenteric drainage on hepatobiliary iminodiacetic acid scan) and 6 (nonpatent) in group B; mean SWE value was 12.8 and 17.3 kPa, respectively ( p  < 0.001). Ten children from group A underwent SWE 6 months postoperatively, and the mean value was 13.23 kPa. Conclusion  The SWE values correlate with liver histology grading, suggesting a reliable alternative to biopsy. Additionally, the baseline SWE values and their trend during follow-up can provide information on the disease's progression.

Brain imaging in children with neonatal cholestatic liver disease: A systematic review

AIM

To determine if children with neonatal cholestatic liver disease had concurrent and later findings on brain imaging studies that could be attributed and the cholestasis to contribute to the understanding of the impaired neuropsychological development.

METHODS

Ovid MEDLINE and EMBASE were searched on July 21, 2022, and updated on March 26, 2023. Studies with children under 18 years of age with neonatal cholestasis and a brain scan at the time of diagnosis or later in life were included. Excluded studies were non-English, non-human, reviews or conference abstracts. Data were extracted on demographics, brain imaging findings, treatment and outcome. The results were summarised by disease categories. Risk of bias was assessed using JBI critical appraisal tools.

RESULTS

The search yielded 12 011 reports, of which 1261 underwent full text review and 89 were eligible for inclusion. Haemorrhage was the most common finding, especially in children with bile duct obstruction, including biliary atresia. Some findings were resolved after liver transplantation.

CONCLUSION

Children with neonatal cholestasis had changes in brain imaging, which might play a role in impaired neuropsychological development, but longitudinal clinical research with structured assessment is needed to better qualify the aetiology of the impairment.

Age-specific reference intervals for liver function tests in healthy neonates, infants, and young children in Iran

BACKGROUND

The reference intervals (RIs) for liver function tests (LFTs) were determined in Iranian children for the first time.

METHODS

A total of 344 healthy pediatrics aged 3 days to 30 months old were recruited. Serum levels of ALT, AST, ALP, direct bilirubin, and total bilirubin were measured. RIs were determined using CLSI Ep28-A3 guidelines.

RESULTS

All analytes demonstrated age-specific differences except AST. ALT and ALP demonstrated significantly elevated levels in infants 0 to <5 months relative to the remainder of the age range. Direct and total bilirubin demonstrated markedly elevated levels in early life with mean of 0.28 mg/dL and 1.64 mg/dL observed for direct and total bilirubin, respectively, decreasing by ~50% in the adjacent partition.

CONCLUSION

These novel data will help improve the clinical interpretation of biochemical test results in young Iranian neonates and children and can be of value to clinical laboratories with similar populations.

Liver elasticity assessment after biliary drainage in patients with extrahepatic cholestasis by shear wave sono-elastography (SWE)

Background

Extrahepatic cholestasis that is caused by benign and malignant diseases has been reported to influence liver elasticity, independent of liver fibrosis. Shear wave sono-elastography is a novel noninvasive ultrasound-based tool to assess liver stiffness that is indirectly measured by the propagation velocity of ultrasound waves within the liver parenchyma. The aim of our study is to explore the impact of extrahepatic cholestasis on liver elasticity assessed by sono-elastography.

Methods

This is the prospective cohort study of 80 patients with obstructive jaundice. Liver elasticity was measured before biliary drainage (day 0), with measures repeated 2 days (day 2) and seven days (day 7) after biliary drainage. Then, correlation with serum bilirubin and serum liver enzymes values was done.

Results

The studied patients with extrahepatic cholestasis (38 males and 42 females with mean age ± SD of 45.8 ± 14.6 years) referred to our department for biliary drainage. All underwent liver elasticity measurement by real-time shear wave sono-elastography before biliary drainage with the highest value of mean elasticity (± SD) 8.44 kPa (± 3.02) and then repeated on day 2 with mean elasticity 6.82 kPa (± 2.77), followed by maximum improvement of liver stiffness on day 7 with mean elasticity 4.8 kPa (± 1.80), coincided with improvement of cholestatic laboratory levels.

Conclusions

This study confirmed improvement of liver stiffness, measured by sono-elastography, after biliary drainage in patients with extrahepatic biliary obstruction.

Diagnostic accuracy of two-dimensional shear wave elastography in detecting hepatic fibrosis in children with autoimmune hepatitis, biliary atresia and other chronic liver diseases

BACKGROUND

Although fibrosis is the main determinant of liver stiffness, other disease-related factors usually disregarded in studies on liver elastography, such as inflammation and cholestasis, may influence liver stiffness.

OBJECTIVE

To evaluate the accuracy of two-dimensional (2-D) shear wave elastography in assessing liver fibrosis in children with chronic liver disease by controlling for the confounding role of several disease- and patient-related factors.

MATERIALS AND METHODS

Three disease groups were studied: 1) various chronic liver diseases, 2) autoimmune hepatitis and 3) biliary atresia. The METAVIR (meta-analysis of histological data in viral hepatitis) score was used for fibrosis staging and grading of necroinflammatory activity. Multiple linear regression was used to evaluate the relationship between liver stiffness measurements and disease-related factors. The diagnostic accuracy of elastography for predicting fibrosis stages was assessed by calculating the area under the receiver operating characteristic curves.

RESULTS

The various chronic liver diseases group (n=32; 7.1±4.9 [mean±standard deviation] years) showed liver stiffness of 8.9±5.0 (mean±standard deviation) kPa, the autoimmune hepatitis group (n=33;  8.1±4.4 years) of  7.1±2.7 kPa, and the biliary atresia group (n=19; 0.2±0.1 years) of 19.7±15.2 kPa. Liver stiffness measurements differed across METAVIR fibrosis categories in all disease groups. The highest values were found in biliary atresia, at fibrosis stages ≥F2 (F2: 12.4±1.6 kPa, F3: 17.8±2 kPa, F4: 41.5±12.4 kPa). Liver stiffness was strongly associated only with fibrosis (P<0.0001) in various chronic liver diseases, but with necroinflammatory activity (P<0.0001) and fibrosis (P=0.002) in autoimmune hepatitis, and with age (P<0.0001), fibrosis (P<0.0001) and cholestasis (P=0.009) in biliary atresia. Optimal cutoffs for detecting advanced fibrosis (≥F3) were 16 kPa (area under curve: 0.98; sensitivity: 87.5%; specificity: 96.7%) in biliary atresia and 8.7 kPa (area under curve: 0.98; sensitivity: 93.8%; specificity: 96.1%) in other chronic liver diseases.

CONCLUSION

Two-dimensional shear wave elastography is reliable in assessing liver fibrosis in children with chronic liver diseases.

Two-Dimensional Shear Wave Elastography Predicts Liver Fibrosis in Jaundiced Infants with Suspected Biliary Atresia: A Prospective Study

Objective

This study aimed to evaluate the role of preoperative two-dimensional (2D) shear wave elastography (SWE) in assessing the stages of liver fibrosis in patients with suspected biliary atresia (BA) and compared its diagnostic performance with those of serum fibrosis biomarkers.

Materials and Methods

This study was approved by the ethical committee, and written informed parental consent was obtained. Two hundred and sixteen patients were prospectively enrolled between January 2012 and October 2018. The 2D SWE measurements of 69 patients have been previously reported. 2D SWE measurements, serum fibrosis biomarkers, including fibrotic markers and biochemical test results, and liver histology parameters were obtained. 2D SWE values, serum biomarkers including, aspartate aminotransferase to platelet ratio index (APRi), and other serum fibrotic markers were correlated with the stages of liver fibrosis by METAVIR. Receiver operating characteristic (ROC) curves and area under the ROC (AUROC) curve analyses were used.

Results

The correlation coefficient of 2D SWE value in correlation with the stages of liver fibrosis was 0.789 (p < 0.001). The cut-off values of 2D SWE were calculated as 9.1 kPa for F1, 11.6 kPa for F2, 13.0 kPa for F3, and 15.7 kPa for F4. The AUROCs of 2D SWE in the determination of the stages of liver fibrosis ranged from 0.869 to 0.941. The sensitivity and negative predictive value of 2D SWE in the diagnosis of ≥ F3 was 93.4% and 96.0%, respectively. The diagnostic performance of 2D SWE was superior to that of APRi and other serum fibrotic markers in predicting severe fibrosis and cirrhosis (all p < 0.005) and other serum biomarkers. Multivariate analysis showed that the 2D SWE value was the only statistically significant parameter for predicting liver fibrosis.

Conclusion

2D SWE is a more effective non-invasive tool for predicting the stage of liver fibrosis in patients with suspected BA, compared with serum fibrosis biomarkers.

Extended Screening for Cystic Fibrosis-related Liver Disease Including Elastography in Children and Adolescents

OBJECTIVES

Advances in treatment of cystic fibrosis (CF) have increased survival and thereby prevalence of patients with liver disease, making chronic liver disease one of the major complications of CF. We describe the prevalence of liver fibrosis, portal hypertension, and liver decompensation by extended screening for cystic fibrosis-related liver disease (CFLD) including ultrasound, elastography, and an extended panel of biochemical markers.

METHODS

A cross sectional study of CFLD in all pediatric CF patients (1-18 years) from the Copenhagen CF Center. Screening for liver disease included physical examination, biochemical analysis, Vibration-Controlled Transient Elastography (FibroScan), conventional ultrasound, and Real-Time Shear Wave elastography (SWE). Patients were scored according to Williams ultrasound scoring scale (WUSS) within 6 months.

RESULTS

A total of 84 consecutive patients (male sex 46.4%, median age 10.4 years) were included. Eight patients (9.5%) had both ≥2 abnormal results of sonographic methods and ≥2 abnormal biochemical results and were in this study categorized as having manifest CFLD. Manifest CFLD patients were significantly older and had a higher mean value of APRI, but no differences in gender, z-height, z-weight, z-BMI, FEV1%, or mean value of bilirubin or albumin were found.

CONCLUSIONS

In total, 8 patients (9.5%) in this pediatric CF population were categorized as having CFLD according to both biochemical and sonographic tests. Consistency was found among the results of FibroScan and SWE. We suggest WUSS and either FibroScan or SWE, combined with GGT as diagnostic markers for CFLD.

Transient elastography correlated with diffusion-weighted magnetic resonance imaging and cholestatic complications

BACKGROUND/PURPOSE

The study aim to investigate the correlation between diffusion-weighted magnetic resonance imaging (DW-MRI) and transient elastography (TE) liver fibrosis findings in children with cholestatic liver diseases, and the utility of TE findings to predict cholestatic complications in children.

METHODS

This cross-sectional study enrolled 36 cholestatic children (21 boys and 15 girls). All study subjects underwent TE and DW-MRI studies to assess liver stiffness. All study subjects were followed prospectively, and their cholestatic complications were analyzed. The optimum cut-off TE value for the prediction of cholestatic complications was determined by receiver operating characteristic (ROC) analysis.

RESULTS

A significant negative correlation between liver stiffness measurements (LSMs) and right-liver-to-psoas apparent diffusion coefficient ratios (LTPARs) was found in the study cohort (correlation coefficient = -0.52, p = 0.001). An LSM cut-off > 8.6 kPa was optimal for predicting complications of cholestasis in 6 months of this cohort (p < 0.001). Survival analysis revealed that an LSM of >8.6 kPa was significantly predictive of cholestatic complications in 6 months (hazard ratio = 4.89; 95% CI = 1.41-16.97; p = 0.01).

CONCLUSION

TE and DW-MRI findings showed a similar ability to predict liver fibrosis in cholestatic children. The LSMs measured by TE are predictive of the occurrence of cholestatic complications in 6 months in children with cholestatic liver diseases.

Pathologic Features of Hereditary Cholestatic Diseases

The inherited diseases causing conjugated hyperbilirubinemia are diverse, with variability in clinical severity, histologic appearance, and time of onset. The liver biopsy appearances can also vary depending on whether the initial presentation is in the neonatal period or later. Although many of the disorders have specific histologic features in fully developed and classic cases, biopsies taken early in the disease course may be nonspecific, showing either cholestatic hepatitis or an obstructive pattern of injury requiring close correlation with the laboratory and clinical findings to reach the correct diagnosis. Additionally, increased understanding of the range of hepatic changes occurring in mild deficiencies of bile canalicular transporter proteins suggest that these disorders, particularly ABCB4 deficiency, may be more common than previously recognized; improved awareness should prompt further investigation.

Placental growth factor promotes epithelial-mesenchymal transition-like changes in ARPE-19 cells under hypoxia

Purpose

To investigate the role of placental growth factor (PGF) in the epithelial-mesenchymal transition (EMT) of ARPE-19 cells under hypoxia, and whether the NF-κB signaling pathway is involved in this process.

Methods

ARPE-19 cells were treated in five groups: a control group, hypoxia group, PGF group, hypoxia+PGF group, and NF-κB-blocked group. A chemical hypoxia model was established in the ARPE-19 cells by adding CoCl₂ to the culture medium. The morphological changes after treatment were observed. The proliferation rates were measured with 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The migration abilities were measured with scratch assay. The EMT biomarkers were measured with quantitative real-time PCR (qRT-PCR), western blotting, and immunofluorescence. The relative protein expression of components of the NF-κB signaling pathway was measured with western blotting and immunofluorescence.

Results

Cells treated with PGF under hypoxia exhibited morphological changes consistent with the transition from an epithelial to a mesenchymal phenotype. In the ARPE-19 cells, exogenous PGF under hypoxia increased the proliferation rate compared to the rate under hypoxia alone (p<0.05) and increased the migration rate (p<0.05). Treatment of hypoxia-exposed cells with PGF caused decreased expression of the epithelial biomarkers E-cadherin and ZO-1 (both p<0.05) and increased expression of the mesenchymal marker α-SMA (p<0.05) by enhancing the phosphorylation of NF-κB p65 of the total protein, promoting the translocation of p65 to the nucleus, and inducing the degradation of IκB-α (a negative regulator of the NF-κB pathway) in the ARPE-19 cells. Additionally, the effect of PGF-induced EMT in the ARPE-19 cells under hypoxia was counteracted with BAY 11-7082 (a selective NF-κB inhibitor).

Conclusions

Exogenous PGF promotes EMT-like changes in ARPE-19 cells under hypoxia by activating the NF-κB signaling pathway. The study results suggest that PGF may play a role in scar formation in neovascular age-related macular degeneration (AMD) and that the inhibition of PGF may be a promising target for the prevention and treatment of AMD.

Effects of calcium Ionophore A23187 on the apoptosis of hepatic stellate cells stimulated by transforming growth factor-β1

Background

Our previous study showed that during in vitro experiments changes in calcium concentration were associated with apoptosis. We presumed that the calcium ion might play a role as intermediate messenger for apoptosis-related genes. No such evidence has been reported in the literature. Here, we investigate the effect of calcium ionophore A23187 on the apoptosis of rat hepatic stellate cells (HSCs) stimulated by transforming growth factor-β₁ (TGF-β₁) to explore the mechanism of apoptosis through the endoplasmic reticulum stress pathway.

Methods

The apoptotic rate was determined using flow cytometry. The changes in Ca²⁺ level in HSCs were examined with laser confocal microscopy. The expressions of caspase-12 GRP78 and caspase-9 were assayed via western blot.

Results

The respective apoptosis rates for the blank group, the TGF-β₁ group and the TGF-β₁ + low, medium and high dose calcium ionophore A23187 groups were 3.40 ± 0.10%, 1.76 ± 0.12%, 5.86 ± 0.31%, 11.20 ± 0.48% and 15.08 ± 0.75%, with significant differences between the groups (p < 0.05). The concentration of Ca²⁺and the expression of the GRP78, caspase-9 and caspase-12 proteins significantly increased with increasing calcium ionophore A23187 doses (p < 0.05).

Conclusion

Calcium ionophore A23187 increased intracellular Ca²⁺ and activated endoplasmic reticulum stress, which promoted HSC apoptosis.

Dynamic relationship between infantile hepatitis syndrome and cytomegalovirus infection

We investigated the correlation between cytomegalovirus (CMV) infection and infantile hepatitis syndrome and the correlation between blood ammonia levels in children with CMV-induced hepatitis syndrome and liver function indicators. To analyze the relationship between the positive-negative attributes of CMV infection and the recurrence rate of infantile hepatitis syndrome, a total of 86 cases of children with hepatitis syndrome admitted to Xuzhou Children's Hospital from January 2014 to March 2015 were selected for the study group. Furthermore, 86 cases of healthy children who visited our hospital for a physical examination during the same period were selected as the control group. From the two groups, serum CMV-immunoglobulin M (IgM) levels were determined via enzyme-linked immunosorbent assay, and urinary CMV-deoxyribonucleic acid (DNA) was ascertained by fluorescent ratio polymerase chain reaction. These levels were then compared between the two groups and analyzed. A fully automatic biochemical analyzer was utilized to evaluate the blood ammonia and liver function indicators of the children with infantile hepatitis syndrome induced by CMV infection and to analyze the correlation of these factors. A mean follow-up of 12 months after the children's discharge was adopted to observe the relationship between the negative-positive attributes of CMV infection and the recurrence rate in the children upon cure. The positive detection rate for the serum CMV-IgM was 24.4%, and that for the urinary CMV-DNA was 34.9%; both values were significantly higher than that for the control group (P<0.05). The blood ammonia levels of the children with infantile hepatitis syndrome induced by CMV infection were not correlated with the liver function indicators, such as total bilirubin, direct bilirubin, alanine aminotransferase, aspartate aminotransferase, γ-glutamyltransferase, total bile acid, and cholinesterase (P>0.05), but they were negatively correlated with blood albumin (ALB) (P<0.05). The recurrence rate of hepatitis syndrome among the children with negative CMV infection was 3.8%, which was significantly lower than that among the children with positive CMV infection (62.5%, P<0.05). A significant correlation was found between CMV infection and infantile hepatitis syndrome, with the former being a risk factor for the latter. Changes in the conditions of infantile hepatitis syndrome may be reflected by blood ammonia and ALB indicators. Through improved monitoring, these indicators facilitate the early diagnosis and treatment of children with hepatitis syndrome induced by CMV infection. Sufficient attention should be paid to preventive measures to reduce the incidence rate of infantile hepatitis syndrome.

Feasibility and Diagnostic Accuracy of Supersonic Shear-Wave Elastography for the Assessment of Liver Stiffness and Liver Fibrosis in Children: A Pilot Study of 96 Patients

PURPOSE

To evaluate the feasibility of using supersonic shear-wave elastography (SSWE) in children and normal values of liver stiffness with the use of control patients of different ages (from neonates to teenagers) and the diagnostic accuracy of supersonic shear wave elastography for assessing liver fibrosis by using the histologic scoring system as the reference method in patients with liver disease, with a special concern for early stages of fibrosis.

MATERIALS AND METHODS

The institutional review board approved this prospective study. Informed consent was obtained from parents and children older than 7 years. First, 51 healthy children (from neonate to 15 years) were analyzed as the control group, and univariate and multivariate comparisons were performed to study the effect of age, transducer, breathing condition, probe, and position on elasticity values. Next, 45 children (from 1 month to 17.2 years old) who underwent liver biopsy were analyzed. SSWE measurements were obtained in the same region of the liver as the biopsy specimens. Biopsy specimens were reviewed in a blinded manner by a pathologist with the use of METAVIR criteria. The areas under the receiver operating characteristics curve (AUCs) were calculated for patients with fibrosis stage F0 versus those with stage F1-F2, F2 or higher, F3 or higher, and F4 or higher.

RESULTS

A successful rate of SSWE measurement was 100% in 96 patients, including neonates. Liver stiffness values were significantly higher when an SC6-1 probe (Aixplorer; SuperSonic Imagine SA, Aix-enProvence, France) was used than when an SL15-4 probe (Aixplorer) was used (mean ± standard deviation, 6.94 kPa ± 1.42 vs 5.96 kPa ± 1.31; P = .006). There was no influence of sex, the location of measurement, or respiratory status on liver elasticity values (P = .41-.93), although the power to detect such a difference was low. According to the degree of liver fibrosis at liver biopsy, 88.5%-96.8% of patients were correctly classified, with AUCs of 0.90-0.98 (95% confidence interval [CI]: 0.8, 1.0). The AUC for patients with stage F0 versus stage F1-F2 was 0.93 (95% CI: 0.87, 0.99).

CONCLUSION

SSWE allows accurate assessment of liver fibrosis, even in children with early stage (F1-F2) disease, and the choice of transducer influences liver stiffness values.

Liver fibrosis during the development of biliary atresia: Proof of principle in the murine model

BACKGROUND

The murine model of biliary atresia (BA) is used for examining the pathogenesis of BA. The aim of the study was description of the morphological features and illustrating the detailed development of fibrosis using the Biliary Atresia Research Consortium (BARC) system.

METHODS

Neonatal mice were injected intraperitoneally with rhesus rotavirus (RRV) strain (N=17). Healthy mice were the control group (N=29). All mice were sacrificed at 7 or 14days after birth. Two pathologists examined the morphological features using the BARC system; CK19, αSMA and collagen type I were assessed by immunohistochemistry.

RESULTS

In RRV mice, portal fibrous expansion with focal bile duct proliferation and strong portal cellular infiltrate was found in contrast to healthy mice. In RRV mice, CK19 bile duct staining was significantly less or absent (p<0.01), with stronger portal staining of collagen type I (p=0.02). Expansion of staining for αSMA was more in RRV mice (p<0.01), but αSMA portal staining was stronger in healthy mice (p=0.02).

CONCLUSIONS

The morphological features observed in the murine model of BA correspond with the BA characteristics according to the BARC criteria. Fibrosis is an important feature of the model. Therefore, this murine model is useful for investigating the pathogenesis of BA.

Combined silencing of TGF-β2 and Snail genes inhibit epithelial-mesenchymal transition of retinal pigment epithelial cells under hypoxia

BACKGROUND

The formation of scar-like fibrous tissue in age-related macular degeneration (AMD) is associated with hypoxia. Under hypoxia, retinal pigment epithelial (RPE) cells can secret more transforming growth factor-β2 (TGF-β2), which is determined to induce epithelial-mesenchymal transition (EMT) at certain concentrations. Whether hypoxia can induce EMT by stimulating RPE cell line secrets TGF-β2 or not remains unknown. To gain a better understanding of the signaling mechanisms of fibrosis in AMD under hypoxic conditions, we investigated EMT in retinal pigment epithelial (RPE) cells and the effect of TGF-β2 and Snail in this process.

METHODS

Human RPE cell line (ARPE-19) was incubated with 5 % O2 for different periods of time. The expression of N-cadherin, α-smooth muscle actin (α-SMA), TGF-β2 , and Snail were determined by Western blot and real-time PCR. Cell proliferation was assessed by CCK8 kit. RNA interference was used for multi-gene silencing of TGF-β2 and Snail genes.

RESULTS

N-cadherin was decreased and mesenchymal cell marker α-SMA was increased after the ARPE-19 cell line was incubated with 5 % O2. Meanwhile, the proliferation capability of the cell line was increased. TGF-β2 and Snail expression were increased in a time-dependent manner under hypoxia. After multi-silencing TGF-β2 and Snail genes, N-cadherin was increased and α-SMA was reduced. Meanwhile, the proliferation of the cell line was suppressed.

CONCLUSIONS

Under hypoxic conditions, RPE cells undergo EMT. Endogenic TGF-β2 and Snail are involved in this process. Furthermore, knockdown of both TGF-β2 and Snail inhibited EMT to a greater extent than knockdown of either gene individually.

Liver disease in cystic fibrosis

The survival of patients with cystic fibrosis (CF) has progressively increased over recent decades, largely attributable to early diagnosis through newborn screening and advances in nutritional and respiratory care. As the life expectancy of patients with CF has improved, non-respiratory complications such as liver disease have become increasingly recognized. Biochemical derangements of liver enzymes in CF are common and may be attributed to a number of specific hepatobiliary abnormalities. Among them, Cystic Fibrosis-associated Liver Disease (CFLD) is clinically the most significant hepatic complication and is believed to have a significant impact on morbidity and mortality. However, there remains much conjecture about the extent of the adverse prognostic implications that a diagnosis of CFLD has on clinical outcomes. The purpose of this review is to give an overview of the current knowledge regarding liver disease in children with CF.

Recent progress in understanding pathogenesis and liver pathology in biliary atresia

Biliary atresia is an infantile destructive inflammatory cholangiopathy that causes obliteration of both intrahepatic and extrahepatic bile ducts and eventually liver cirrhosis. So far, the exact etiology and pathogenesis of biliary atresia remain unclear, and possible etiologies include congenital and genetic factors, infection, inflammation, immune reaction, maternal factors, and vascular factors. Immunoinflammatory theory has been accepted by most researchers, which is supported by liver pathological changes. This review focuses on the recent progress in understanding pathogenesis and liver pathology in biliary atresia.

Bone metabolism in cholestatic children before and after living-related liver transplantation--a long-term prospective study

Bone disorders are common in children with end-stage liver diseases, especially those associated with cholestasis. Abnormal hepatocyte function, disordered vitamin D metabolism and calcium-phosphorous homeostasis, malnutrition, and immunosuppressive treatment are potential risk factors of bone tissue pathology before and after transplantation. The aim of the study was to analyze the long-term effect of successful living-related liver transplantation (LRLTx) on skeletal status and bone metabolism in cholestatic children. Eighteen cholestatic children (1.4±0.5yr old; 12 females [F]/6 males [M]) qualified for LRLTx were analyzed; 16 (5F/11M) of them participated in long-term observation (V4). Serum levels of osteocalcin (OC), procollagen type 1 N-terminal propeptide (P1NP), cross-linked telopeptide of type 1 collagen (CTx), insulin-like growth factor I (IGF-I), IGF-I binding protein 3 (IGFBP-3), parathyroid hormone (PTH), 25-hydroxyvitamin D (25(OH)D), and 1,25-dihydroxyvitamin D (1,25(OH)(2)D) were assayed before (V0) and 6mo (V1), 12mo (V2), 18mo (V3), and 4.4yr (V4) after LRLTx. Total body bone mineral content (TBBMC) and total body bone mineral density (TBBMD) were measured by dual-energy X-ray absorptiometry (DXA) at the same pattern. Before LRLTx, the OC, P1NP, CTx, IGF-I, and IGFBP-3 levels as well as TBBMC and TBBMD were decreased compared with age-matched control group. The mean serum levels of 25(OH)D and 1,25(OH)(2)D were within reference ranges from V0 to V4. After LRLTx, the OC, P1NP, CTx, IGF-I, and IGFBP-3 as well as TBBMC and TBBMD reached the age-matched reference values. At V4, the level of P1NP decreased below and the PTH increased above the reference range that coincided with reduced Z-scores of both TBBMC (-1.11±1.24) and TBBMD (-1.00±1.19). P1NP and CTx, both measured at V3, correlated with IGF-I at V2 (R=0.86, p=0.014 and R=0.78, p=0.021, respectively) and PTH at V3 for P1NP and V1 for CTx (R=0.64, p=0.048 and R=0.54, p=0.038, respectively). The TBBMC changes between V0 and V4 correlated with IGF-I (R=0.68, p=0.015) and 1,25(OH)(2)D (R=0.54, p=0.025), both assayed at V1. The change of TBBMC Z-scores between V0 and V4 correlated with P1NP at V1 (R=0.69, p=0.002). The TBBMD changes between V0 and V4 correlated with CTx at V1 (R=0.54, p=0.027) and P1NP change between V0 and V1 (R=0.51, p=0.038). In short-term observation, successful LRLTx led to bone metabolism normalization triggered by probable anabolic action of IGF-I and PTH and manifested by TBBMC and TBBMD increases. In long-term horizon, moderately impaired DXA assessed bone status coincided with disturbances in bone metabolism. Bone metabolism markers, especially P1NP and CTx, appeared to be good predictors of changes in bone status evaluated by DXA.

Liver disease in cystic fibrosis

PURPOSE OF REVIEW

This review looks at what is currently known about liver disease in cystic fibrosis (CF) in light of the literature over the past year, and what the ongoing challenges are from a clinical and research perspective for the optimal management of cystic fibrosis liver disease (CFLD).

RECENT FINDINGS

Patients with CF who develop clinically significant liver disease have a worse overall phenotype, and whereas there is no definite evidence that they have a shorter life expectancy, longer follow-up is required to determine if liver disease is a risk factor for mortality in CF.The development of the ferret and pig animal models of CF with multiorgan involvement is an important breakthrough which will enhance our understanding of the pathogenesis of CFLD, and with which it is hoped novel therapeutic targets for the treatment of CFLD will be identified.

SUMMARY

Whereas there is still no effective treatment for liver disease in CF, recent developments of animal models of CFLD will enhance our capacity to develop new therapeutic targets and reduce the impact of liver disease on mortality in CF.