Serum sterols in patients with primary biliary cirrhosis and acute liver failure before and after liver transplantation

One year of treatment with elexacaftor/tezacaftor/ivacaftor in patients with cystic fibrosis homozygous for the F508del mutation causes a significant increase in liver biochemical indexes

Introduction: Modulators of cystic fibrosis transmembrane conductance regulator mutated protein significantly improved the outcome of patients with cystic fibrosis (CF). We describe 63 patients who were independently followed up in two CF regional centers (i.e., Campania and Tuscany regions). Methods: All patients were homozygous for the F508del mutation and were treated with lumacaftor/ivacaftor (LI) for 3 years, followed by 1 year of treatment with elexacaftor/tezacaftor/ivacaftor (ETI). We studied the biochemical parameters of liver damage and cholesterol metabolism. Results: Beyond the improvement of BMI and lung function with LI treatment and even more with ETI, we found that the 3 years of LI treatment significantly improved liver function parameters (total and conjugated bilirubin, ALT, AP, and GGT), while the subsequent ETI treatment caused a significant increase of such parameters. Discussion: We confirm that treatment with LI does not correct hypocholesterolemia, whereas treatment with ETI significantly increases serum cholesterol. Such an increase is likely due to enhanced de novo biosynthesis, as indicated by the significant increase in serum lathosterol, and it is likely that the subsequent liver cholesterol accumulation may contribute to triggering inflammation and worsening liver biochemical indexes. The increase in serum bilirubin and ALT that we observed in approximately 94% and 84% of patients treated with ETI, respectively, suggests further investigation of the impact of ETI therapy on liver function indexes.

Mapping of de novo mutations in primary biliary cholangitis to a disease-specific co-expression network underlying homeostasis and metabolism

Primary biliary cholangitis (PBC) is an autoimmune disease involving dysregulation of a broad array of homeostatic and metabolic processes. Although considerable single-nucleotide polymorphisms have been unveiled, a large fraction of risk factors remains enigmatic. Candidate genes with rare mutations that tend to confer more deleterious effects need to be identified. To help pinpoint cellular and developmental mechanisms beyond common noncoding variants, we integrated whole exome sequencing with integrative network analysis to investigate genes harboring de novo mutations. Prominent convergence has been revealed on a network of disease-specific co-expression comprised of 55 genes associated with homeostasis and metabolism. The transcription factor MEF2D and the DNA repair gene PARP2 were highlighted as hub genes and identified to be up- and down-regulated, respectively, in peripheral blood data set. Enrichment analysis demonstrated altered expression of MEF2D and PARP2 may trigger a series of molecular and cellular processes with pivotal roles in PBC pathophysiology. Our study identified genes with de novo mutations in PBC and suggested a subset of genes in homeostasis and metabolism tend to act in synergy through converging on co-expression network, providing novel insights into the etiology of PBC and expanding the pool of molecular candidates for discovering clinically actionable biomarkers.

Age-related changes of cholestanol and lathosterol plasma concentrations: an explorative study

BACKGROUND

Cerebrotendinous xanthomatosis (CTX) and Lathosterolosis represent two treatable inherited disorders of cholesterol metabolism that are characterized by the accumulation of cholestanol and lathosterol, respectively. The age of the patients suspected of having these disorders is highly variable due to the very different phenotypes. The early diagnosis of these disorders is important because specific therapeutic treatment could prevent the disease progression. The biochemical diagnosis of these defects is generally performed analyzing the sterol profile. Since age-related levels of these sterols are lacking, this study aims to determine a preliminary comparison of plasma levels of cholestanol and lathosterol among Italian unaffected newborns, children and healthy adults.

METHODS

The sterols were extracted from 130 plasma samples (24 newborns, 33 children and 73 adults) by a liquid-liquid separation method and quantified by gas chromatography coupled with a flame ionization detector.

RESULTS

Cholesterol, cholestanol and lathosterol levels together with the cholestanol/cholesterol and lathosterol/cholesterol ratios are statistically different among the three groups. Cholesterol levels progressively increased from newborns to children and to adults, whereas cholestanol/cholesterol and cholestanol/lathosterol ratios progressively decreased from newborns to children and to adults. Lathosterol levels were higher in adults than in both newborns and children. In the total population a positive correlation was observed between cholesterol levels and both cholestanol (correlation coefficient = 0.290, p = 0.001) and lathosterol levels (correlation coefficient = 0.353, p <  0.0001).

CONCLUSIONS

Although this study can only be considered an explorative experience due to the low number of analyzed samples, we revealed several differences of plasma cholestanol and lathosterol levels and their ratios to cholesterol levels among newborns, children and adults. These evidences indicate the need of age-related reference values of cholestanol and lathosterol concentrations, including also newborns and children.

Age-related changes of cholestanol and lathosterol plasma concentrations: an explorative study

BACKGROUND

Cerebrotendinous xanthomatosis (CTX) and Lathosterolosis represent two treatable inherited disorders of cholesterol metabolism that are characterized by the accumulation of cholestanol and lathosterol, respectively. The age of the patients suspected of having these disorders is highly variable due to the very different phenotypes. The early diagnosis of these disorders is important because specific therapeutic treatment could prevent the disease progression. The biochemical diagnosis of these defects is generally performed analyzing the sterol profile. Since age-related levels of these sterols are lacking, this study aims to determine a preliminary comparison of plasma levels of cholestanol and lathosterol among Italian unaffected newborns, children and healthy adults.

METHODS

The sterols were extracted from 130 plasma samples (24 newborns, 33 children and 73 adults) by a liquid-liquid separation method and quantified by gas chromatography coupled with a flame ionization detector.

RESULTS

Cholesterol, cholestanol and lathosterol levels together with the cholestanol/cholesterol and lathosterol/cholesterol ratios are statistically different among the three groups. Cholesterol levels progressively increased from newborns to children and to adults, whereas cholestanol/cholesterol and cholestanol/lathosterol ratios progressively decreased from newborns to children and to adults. Lathosterol levels were higher in adults than in both newborns and children. In the total population a positive correlation was observed between cholesterol levels and both cholestanol (correlation coefficient = 0.290, p = 0.001) and lathosterol levels (correlation coefficient = 0.353, p <  0.0001).

CONCLUSIONS

Although this study can only be considered an explorative experience due to the low number of analyzed samples, we revealed several differences of plasma cholestanol and lathosterol levels and their ratios to cholesterol levels among newborns, children and adults. These evidences indicate the need of age-related reference values of cholestanol and lathosterol concentrations, including also newborns and children.

Noncholesterol Sterols as Surrogate Markers in Patients with Severe Alcoholic Hepatitis

Severe alcoholic hepatitis (AH) is a life-threatening condition lacking good serologic markers to tailor treatment and predict recovery. We examined the cholesterol metabolism in severe AH to explore prognostic markers and evaluate the profile of cholesterol precursors, cholestanol and phytosterols, in this context. We assessed serum cholesterol, cholesterol precursors, cholestanol, phytosterols, and biochemical markers in 24 patients with severe AH treated with prednisolone and randomized to ciprofloxacin in the ratio 1:1. Response to prednisolone was assessed with the Lille model. Evaluations were made between responders and nonresponders to corticosteroid treatment and during follow-up for 180 days. The findings were compared with those from patients with primary sclerosing cholangitis (PSC) (n = 156) and healthy individuals (n = 124). Responders to prednisolone had ~56-60% higher (p-value 0.032-0.044) serum ratios to cholesterol of phytosterols, while the lathosterol/campesterol ratio was ~76% (p = 0.031) lower compared to nonresponders. Stigmasterol/cholesterol predicted response to corticosteroid therapy. Surrogate markers of cholesterol synthesis (lathosterol and desmosterol) inversely reflected those of absorption (cholestanol and phytosterols) in PSC and controls (r-range -0.247 to -0.559, p < 0.01 for all), contrary to AH patients, among whom this reciprocal regulation was partially recovered on day 90 (lathosterol: r-range -0.733 to -0.952, p < 0.05 for all). AH patients had ~26% lower lathosterol/cholesterol, but 1.13-3.87-fold higher cholestanol/cholesterol and sitosterol/cholesterol compared to control groups (p < 0.05 for all). Median ferritin concentration at baseline was ~37% lower (p = 0.011) among the responders. Cholesterol precursors and phytosterols have a disease-specific profile in AH. Phytosterols and ferritin may serve as surrogate markers for short-term response.

Role of the postoperative cholesterol in early allograft dysfunction and survival after living donor liver transplantation

BACKGROUND

Many studies have confirmed that serum total cholesterol (sTC) concentrations were associated with underlying liver damage and the synthesis capacity of liver. However, the role of postoperative sTC level on evaluating graft function and predicting survival of recipients who underwent liver transplantation has not been discussed.

METHODS

Clinical data of 231 living donor liver transplantation recipients from May 2003 to January 2015 were retrospectively collected. Patients were stratified into the low sTC group (sTC <1.42 mmol/L, 57 recipients) and high sTC group (sTC =1.42 mmol/L, 174 recipients) according the sTC level on postoperative day 3 based on receiver-operating characteristic curve analysis. The clinical characteristics and postoperative short- and long-term outcomes were compared between the two groups.

RESULTS

Recipients with sTC <1.42 mmol/L experienced more severe preoperative disease conditions, a higher incidence of postoperative early allograft dysfunction (38.6% vs 10.3%, P<0.001), 90-day mortality (28.1% vs 10.9%, P=0.002) and severe complications (29.8% vs 17.2%, P=0.041) compared to recipients with sTC =1.42 mmol/L. The multivariate analysis demonstrated that sTC <1.42 mmol/L had a 4.08-fold (95% CI: 1.83-9.11, P=0.001) and 2.72-fold (95% CI: 1.23-6.00, P=0.013) greater risk of developing allograft dysfunction and 90-day mortality, and patients with sTC <1.42 mmol/L had poorer overall recipient and graft survival rates at 1-, 3-, and 5-year than those with sTC =1.42 mmol/L (67%, 61% and 61% vs 83%, 71% and 69%, P=0.025; 65%, 59% and 59% vs 81%, 68% and 66%, P=0.026, respectively). Cox multivariate analysis showed that sTC <1.42 mmol/L was an independent predicting factor for total recipient survival (HR=2.043; 95% CI: 1.173-3.560; P=0.012) and graft survival (HR=1.905; 95% CI: 1.115-3.255; P=0.018).

CONCLUSIONS

sTC <1.42 mmol/L on postoperative day 3 was an independent risk factor of postoperative early allograft dysfunction, 90-day mortality, recipient and graft survival, which can be used as a marker for predicting postoperative short- and long-term outcomes.

Low Childhood Cholesterol Absorption Predisposes to Gallstone Disease: The Cardiovascular Risk in Young Finns Study

OBJECTIVES

Unraveling pathogenesis of gallstones could help to diminish its enormous disease burden. We hypothesized that certain properties of childhood cholesterol metabolism predict gallstone disease in adulthood.

METHODS

Childhood serum cholestanol and plant sterols (surrogates for cholesterol absorption), cholesterol precursors (surrogates for cholesterol synthesis), lipids, demographics, and dietary habits were compared between individuals diagnosed with gallstone disease subsequently in adulthood (n = 95) and control subjects (n = 190) matched for age, sex, and body mass index in 1980. Subjects were participants of prospective Cardiovascular Risk in Young Finns Study.

RESULTS

In 1980, at mean age of 11.4 years gallstone cohort was characterized by 5.8% lower cholestanol (P = 0.038), and 11.2% to 12.2% (P range = 0.003-0.008) lower plant sterols campesterol, sitosterol, and avenasterol compared with controls. Mean lathosterol/sitosterol ratio was 16.3% higher in gallstone compared with control cohort (P = 0.028). Female gallstone group had 5.4% lower mean cholestanol compared with controls (P < 0.05), and, respectively, those of campesterol, sitosterol, and avenasterol were 12.7% to 14.0% lower (P < 0.05 for each). Body mass index was inversely related to cholestanol and sitosterol (r range = -0.161 to -0.208, P < 0.05 for each) in controls, but not among patients with gallstone. In whole study population, surrogates of cholesterol absorption (eg, campesterol, P = 0.018) and low dietary intake of vegetables (P = 0.009) were significant predictors of gallstones in logistic regression model.

CONCLUSIONS

Cholesterol metabolism trait characterized by low serum levels of surrogate markers of cholesterol absorption precedes adult gallstone disease already in childhood. Low serum cholestanol and plant sterol ratios during normal Western diet may have role as predictive biomarkers for gallstones.

The Interpretation of Cholesterol Balance Derived Synthesis Data and Surrogate Noncholesterol Plasma Markers for Cholesterol Synthesis under Lipid Lowering Therapies

The cholesterol balance procedure allows the calculation of cholesterol synthesis based on the assumption that loss of endogenous cholesterol via fecal excretion and bile acid synthesis is compensated by de novo synthesis. Under ezetimibe therapy hepatic cholesterol is diminished which can be compensated by hepatic de novo synthesis and hepatic extraction of plasma cholesterol. The plasma lathosterol concentration corrected for total cholesterol concentration (R_Lath) as a marker of de novo cholesterol synthesis is increased during ezetimibe treatment but unchanged under treatment with ezetimibe and simvastatin. Cholesterol balance derived synthesis data increase during both therapies. We hypothesize the following. (1) The cholesterol balance data must be applied to the hepatobiliary cholesterol pool. (2) The calculated cholesterol synthesis value is the sum of hepatic de novo synthesis and the net plasma-liver cholesterol exchange rate. (3) The reduced rate of biliary cholesterol absorption is the major trigger for the regulation of hepatic cholesterol metabolism under ezetimibe treatment. Supportive experimental and literature data are presented that describe changes of cholesterol fluxes under ezetimibe, statin, and combined treatments in omnivores and vegans, link plasma R_Lath to liver function, and define hepatic de novo synthesis as target for regulation of synthesis. An ezetimibe dependent direct hepatic drug effect cannot be excluded.

Cholesterol metabolism in cholestatic liver disease and liver transplantation: From molecular mechanisms to clinical implications

The aim of this review is to enlighten the critical roles that the liver plays in cholesterol metabolism. Liver transplantation can serve as gene therapy or a source of gene transmission in certain conditions that affect cholesterol metabolism, such as low-density-lipoprotein (LDL) receptor gene mutations that are associated with familial hypercholesterolemia. On the other hand, cholestatic liver disease often alters cholesterol metabolism. Cholestasis can lead to formation of lipoprotein X (Lp-X), which is frequently mistaken for LDL on routine clinical tests. In contrast to LDL, Lp-X is non-atherogenic, and failure to differentiate between the two can interfere with cardiovascular risk assessment, potentially leading to prescription of futile lipid-lowering therapy. Statins do not effectively lower Lp-X levels, and cholestasis may lead to accumulation of toxic levels of statins. Moreover, severe cholestasis results in poor micellar formation, which reduces cholesterol absorption, potentially impairing the cholesterol-lowering effect of ezetimibe. Apolipoprotein B-100 measurement can help distinguish between atherogenic and non-atherogenic hypercholesterolemia. Furthermore, routine serum cholesterol measurements alone cannot reflect cholesterol absorption and synthesis. Measurements of serum non-cholesterol sterol biomarkers - such as cholesterol precursor sterols, plant sterols, and cholestanol - may help with the comprehensive assessment of cholesterol metabolism. An adequate cholesterol supply is essential for liver-regenerative capacity. Low preoperative and perioperative serum cholesterol levels seem to predict mortality in liver cirrhosis and after liver transplantation. Thus, accurate lipid profile evaluation is highly important in liver disease and after liver transplantation.

ESPGHAN Committee on Nutrition Position Paper. Intravenous Lipid Emulsions and Risk of Hepatotoxicity in Infants and Children: a Systematic Review and Meta-analysis

The aim of the present article was to perform a systematic review with meta-analysis of available scientific evidence regarding the role of different intravenous lipid emulsions (ILE) in the pathogenesis of cholestasis and parenteral nutrition-associated liver disease. A systematic review of the literature (up to March 2015) identified 23 randomized controlled trials (RCTs). Of these, 17 were performed in preterm infants or critically ill neonates with a short duration of intervention, 2 in older children with short-term use (following surgery or bone marrow transplantation), 1 in neonates with long-term use, and 3 in infants and children receiving long-term parenteral nutrition (PN). Meta-analysis showed no differences in the rate of cholestasis or bilirubin levels associated with short-term use of different ILEs. Because of high heterogeneity of the long-term studies no meta-analysis could be performed. Available studies found that the use of multicomponent fish oil (FO)-containing ILE compared with pure soya bean oil (SO), ILE-reduced liver enzymes, and bilirubin levels in noncholestatic children on long-term PN and one other RCT found that FO-based ILE-reversed cholestasis in a proportion of patients. The ESPGHAN Committee on Nutrition concludes that there is no evidence of a difference in rates of cholestasis or bilirubin levels between different ILE for short-term use in neonates. The use of multicomponent FO-containing ILE may contribute to a decrease in total bilirubin levels in children with IF on prolonged PN. Well-designed RCTs are, however, lacking and long-term effects have not been determined.

Circulating sterols as predictors of early allograft dysfunction and clinical outcome in patients undergoing liver transplantation

INTRODUCTION

Sensitive and specific assessment of the hepatic graft metabolism after liver transplantation (LTX) is essential for early detection of postoperative dysfunction implying the need for consecutive therapeutic interventions.

OBJECTIVES

Here, we assessed circulating liver metabolites of the cholesterol pathway, amino acids and acylcarnitines and evaluated their predictive value on early allograft dysfunction (EAD) and clinical outcome in the context of LTX.

METHODS

The metabolites were quantified in the plasma of 40 liver graft recipients one day pre- and 10 days post-LTX by liquid chromatography/tandem mass spectrometry (LC-MS/MS). Plant sterols as well as cholesterol and its precursors were determined in the free and esterified form; lanosterol in the free form only. Metabolites and esterification ratios were compared to the model for early allograft function scoring (MEAF) which is calculated at day 3 post-LTX from routine parameters defining EAD.

RESULTS

The hepatic esterification ratio of all sterols, but not amino acids and acylcarnitine concentrations, showed substantial metabolic disturbances post-LTX and correlated to the MEAF. In ROC analysis, the low esterification ratio of β-sitosterol and stigmasterol from day 1 and of the other sterols from day 3 were predictive for a high MEAF, i.e. EAD. Additionally, the ratio of esterified β-sitosterol and free lanosterol were predictive for all days and the esterification ratio of the other sterols at day 3 or 4 post-LTX for 3-month mortality.

CONCLUSION

Low ratios of circulating esterified sterols are associated with a high risk of EAD and impaired clinical outcome in the early postoperative phase following LTX.

Circulating Lipids Are Associated with Alcoholic Liver Cirrhosis and Represent Potential Biomarkers for Risk Assessment

Liver disease is the greatest cause of death related to alcohol and a major public health problem. While excessive alcohol intake results in hepatosteatosis in most individuals, this can progress in some to more severe forms of liver disease including fibrosis and cirrhosis. An ongoing challenge in the management of alcoholic liver disease is the identification of liver injury early in the disease process such that intervention strategies can prevent serious long term outcomes. Given that excessive alcohol consumption results in dysregulation of lipid metabolism we applied lipid profiling technology to characterise and compare serum lipid profiles from excessive chronic drinkers with no liver disease to those with advanced alcoholic cirrhosis. In a cohort of 59 excessive drinkers (31 with liver cirrhosis and 28 with no evidence of liver disease) we used electrospray ionisation tandem mass spectrometry to measure over 300 individual lipid species in serum, including species of the major phospholipid, sphingolipid, glycerolipid and sterol classes. Six of the 25 lipid classes and subclasses were significantly associated with alcoholic liver cirrhosis; these included dihexosylceramide, trihexosylceramide, alkylphosphatidylcholine, lysoalkylphosphatidylcholine, phosphatidylinositol and free cholesterol. Multivariate classification models created with only clinical characteristics gave an optimal model with an AUC of 0.847 and an accuracy of 79.7%. The addition of lipid measurements to the clinical characteristics resulted in models of improved performance with an AUC of 0.892 and accuracy of 81.8%. The gain in AUC and accuracy of the combined models highlight the potential of serum lipids as markers of liver injury in alcoholic liver disease.

Serum plant sterols, cholestanol, and cholesterol precursors associate with histological liver injury in pediatric onset intestinal failure

BACKGROUND

Increased serum concentrations of plant sterols, including stigmasterol, during parenteral nutrition (PN) have been linked with serum biochemical signs of intestinal failure-associated liver disease (IFALD), whereas clinical data on their correlation to histologic liver injury have been limited.

OBJECTIVE

We studied interrelations between serum noncholesterol sterols and histologic liver injury in pediatric-onset intestinal failure (IF).

DESIGN

Serum plant sterols (stigmasterol, avenasterol, sitosterol, and campesterol), cholestanol, and cholesterol precursors (cholestenol, lathosterol, and desmosterol) were measured in 50 IF patients at a median age 7.3 y and in 86 matched controls. Forty patients underwent liver biopsies. Sixteen patients had been receiving PN for 45 mo, and 34 patients had received PN for 9.1 mo but had not received PN for 5.4 y.

RESULTS

Serum plant sterols were higher in patients who were currently receiving PN than in controls and were related to conjugated bilirubin (r = 0.799-0.541, P < 0.05). During PN, the ratio of serum stigmasterol to cholesterol was 3.3-fold higher in patients with portal inflammation, and the ratio of avenasterol to cholesterol was 3.9-fold higher in patients with cholestasis (P < 0.05 for both). Ratios of stigmasterol and avenasterol to cholesterol were correlated with portal inflammation (r = 0.549-0.510, P < 0.05), cholestasis (r = 0.501-0.491, P = 0.048-0.053), and serum bile acids (r = 0.591-0.608, P < 0.05). The median (IQR) ratio of serum cholestanol to cholesterol was higher during (269 100× μg/mg cholesterol; 203-402 100× μg/mg cholesterol) than after (175 100× μg/mg cholesterol; 156-206 100× μg/mg cholesterol; P < 0.001) weaning off PN and was correlated with cholestasis (r = 0.428), portal inflammation (r = 0.511), and fibrosis (r = 0.323, P < 0.05 for all). After weaning off PN, ratios of cholestenol and lathosterol to cholesterol were >2-fold higher in patients with persistent liver steatosis than in those without steatosis or controls (P < 0.01 for all), whereas lathosterol was correlated with the steatosis grade (r = 0.320, P < 0.050).

CONCLUSIONS

Increased serum stigmasterol and avenasterol concentrations parallel the portal inflammation and cholestasis during PN, thereby reinforcing their contribution to IFALD. A bile acid malabsorption-driven increase in cholesterol synthesis underpins persistent liver steatosis after weaning off PN. Serum cholestanol reflects liver injury in IF patients.

Severe hypercholesterolemia and phytosterolemia with extensive xanthomas in primary biliary cirrhosis: role of biliary excretion on sterol homeostasis

Primary biliary cirrhosis (PBC) is an autoimmune, chronic, cholestatic liver disease that affects primarily women. PBC is commonly associated with hypercholesterolemia that has been associated with cholestasis. We report an exceptionally high blood cholesterol and phytosterols with just mild cholestasis indicating a selective defect in sterol biliary secretion in a patient with PBC.

A novel fibrosis index comprising a non-cholesterol sterol accurately predicts HCV-related liver cirrhosis

Diagnosis of liver cirrhosis is essential in the management of chronic hepatitis C virus (HCV) infection. Liver biopsy is invasive and thus entails a risk of complications as well as a potential risk of sampling error. Therefore, non-invasive diagnostic tools are preferential. The aim of the present study was to create a model for accurate prediction of liver cirrhosis based on patient characteristics and biomarkers of liver fibrosis, including a panel of non-cholesterol sterols reflecting cholesterol synthesis and absorption and secretion. We evaluated variables with potential predictive significance for liver fibrosis in 278 patients originally included in a multicenter phase III treatment trial for chronic HCV infection. A stepwise multivariate logistic model selection was performed with liver cirrhosis, defined as Ishak fibrosis stage 5–6, as the outcome variable. A new index, referred to as Nordic Liver Index (NoLI) in the paper, was based on the model: Log-odds (predicting cirrhosis) = −12.17+ (age×0.11) + (BMI (kg/m²)×0.23) + (D₇-lathosterol (μg/100 mg cholesterol)×(−0.013)) + (Platelet count (x10⁹/L)×(−0.018)) + (Prothrombin-INR×3.69). The area under the ROC curve (AUROC) for prediction of cirrhosis was 0.91 (95% CI 0.86–0.96). The index was validated in a separate cohort of 83 patients and the AUROC for this cohort was similar (0.90; 95% CI: 0.82–0.98). In conclusion, the new index may complement other methods in diagnosing cirrhosis in patients with chronic HCV infection.

Parenteral plant sterols and intestinal failure-associated liver disease in neonates

OBJECTIVES

We prospectively evaluated incidence of prolonged (>28 days) parenteral nutrition (PN), associated complications, and significance of parenteral plant sterols (PS) in neonatal intestinal failure-associated liver disease (IFALD) compared with children.

METHODS

We recruited 28 neonates (mean age 50 days, range 28-126) and 11 children (6.9 y, 2.1-16.6) in all of Finland. Patients underwent repeated measurements of serum cholesterol, noncholesterol sterols, including PS, cholestanol and cholesterol precursors, and liver biochemistry during and 1 month after discontinuation of PN. Healthy matched neonates (n=10) and children (n=22) served as controls.

RESULTS

IFALD occurred more frequently among neonates (63%) than children (27%; P<0.05). Ratios of serum PS, including stigmasterol, sitosterol, avenasterol, and campesterol, and total PS were increased among neonates compared with healthy controls and children on PN by 2- to 22- and 2- to 5-fold (P<0.005), respectively. Neonates with IFALD had significantly higher ratios of serum PS and cholestanol compared with neonates without IFALD (P<0.05). Total duration of PN associated with serum cholestanol, stigmasterol, avenasterol, alanine aminotransferase, and aspartate aminotransferase (r=0.472-0.636, P<0.05). Cholestanol and individual serum PS, excluding campesterol, reflected direct bilirubin (r=0.529-0.688, P<0.05). IFALD persisted after discontinuation of PN in 25% of neonates with 4.2- and 2.2-times higher ratios of serum stigmasterol and cholestanol compared with neonates without IFALD (P<0.05).

CONCLUSIONS

Frequent occurrence of IFALD among neonates on PN displays an association to duration of PN and markedly increased serum PS, especially stigmasterol, in comparison to healthy neonates and children on PN. Striking accumulation of parenteral PS may contribute to IFALD among neonates.

Effects of long-term parenteral nutrition on serum lipids, plant sterols, cholesterol metabolism, and liver histology in pediatric intestinal failure

BACKGROUND AND OBJECTIVE

Plant sterols (PS) in parenteral nutrition (PN) may contribute to intestinal failure-associated liver disease. We investigated interrelations between serum PS, liver function and histology, cholesterol metabolism, and characteristics of PN.

PATIENTS AND METHODS

Eleven patients with intestinal failure (mean age 6.3 years) receiving long-term PN were studied prospectively (mean 254 days) and underwent repeated measurements of serum lipids, noncholesterol sterols, including PS, and liver enzymes. PS contents of PN were analyzed. Liver biopsy was obtained in 8 patients. Twenty healthy children (mean age 5.7 years) served as controls.

RESULTS

Median percentage of parenteral energy of total daily energy (PN%) was 48%, including 0.9 g · kg(-1) · day(-1) of lipids. Respective amounts of PN sitosterol, campesterol, avenasterol, and stigmasterol were 683, 71, 57, and 45 μg · kg(-1) · day(-1). Median serum concentrations of sitosterol (48 vs 7.5 μmol/L, P < 0.001), avenasterol (2.9 vs 1.9, P < 0.01), stigmasterol (1.9 vs 1.2, P < 0.005), but not that of campesterol (9.8 vs 12, P = 0.22), were increased among patients in relation to controls, and correlated with PN% (r = 0.81-0.88, P < 0.005), but not with PN fat. Serum cholesterol precursors were higher in patients than in controls. Serum liver enzymes remained close to normal range. Glutamyl transferase correlated with serum PS (r = 0.61-0.62, P < 0.05). Liver fibrosis in 5 patients reflected increased serum PS (r = 0.55-0.60, P = 0.16-0.12).

CONCLUSIONS

Serum PS moderately increase during olive oil-based PN, and correlate positively with PN% and glutamyl transferase. Despite well-preserved liver function, histology often revealed significant liver damage.

Surrogate markers of cholesterol metabolism in children with native liver after successful portoenterostomy for biliary atresia

PURPOSE

Cholestasis gradually ensues after portoenterostomy for biliary atresia (BA) and may deteriorate liver function. Cholesterol metabolism and its relationships with serum markers of liver function were evaluated in children living with native liver after successful portoenterostomy for BA.

SUBJECTS AND METHODS

Serum lipids, noncholesterol sterol ratios to cholesterol, that is, surrogate markers of cholesterol metabolism, and liver function were cross-sectionally studied in 17 consecutive children after successful (postoperative bilirubin <20 micromol/L) portoenterostomy for BA with native liver and a mean age of 5.2 years. The results were compared with healthy age-matched controls.

RESULTS

Mean serum total and low-density lipoprotein cholesterol and campesterol ratio were 18%, 43%, and 26% less than those of controls, respectively (P < .01 for all). Despite low serum cholesterol and campesterol (marker of cholesterol absorption) levels, serum lathosterol (marker of cholesterol synthesis) was decreased by 34% (P < .0001) from control levels and reflected serum prealbumin (r = 0.666) and cholestanol (r = -0.515, P < .05 for both). Cholestanol, twice higher than those of controls (P < .0001), reflected abnormally high serum alkaline phosphatase, glutamyl transferase, and bile acids (r = 0.558-0.711, P < .05). Serum campesterol was inversely related with lathosterol (r = -0.238, P < .05) in controls, but not in patients (r = -0.039).

CONCLUSION

Children living with native liver after portoenterostomy for BA are inclined to low serum concentration and absorption of cholesterol. Cholesterol homeostasis was disturbed so that low cholesterol absorption was not associated with compensatory increase in cholesterol synthesis that decreased together with worsening of cholestasis.