Impaired release of vitamin A from liver in primary biliary cirrhosis

Serum vitamins and homocysteine levels in autoimmune liver disease: A systematic review and meta-analysis

OBJECTIVE

Vitamins and homocysteine (Hcy) are involved in liver metabolism and related to the pathogenesis of autoimmune liver disease (AILD), but consensus is lacking. This study aims to systematically summarize relevant evidence to clarify the association of serum vitamins and Hcy levels with AILD.

METHODS

The English and Chinese literature was searched until August 29, 2023. Studies were included if they were observational studies of investigating serum vitamins and Hcy levels in patients with AILD and their healthy comparisons. Quality assessment was performed by using the Newcastle-Ottawa Scale, and a meta-analysis was conducted using ReviewManager 5.3. The protocol was registered in the international prospective register of systematic reviews (PROSPERO), with registration number CRD42023455367.

RESULTS

A total of 25 case-control studies comprising 3487 patients (1673 patients and 1814 healthy controls) were included for analysis. There were 548 autoimmune hepatitis (AIH) cases, 1106 primary biliary cholangitis (PBC) cases, and 19 primary sclerosing cholangitis (PSC) cases. We found that serum A and E were decreased in both AIH and PBC/PSC; but vitamin C was reduced only in patients with PBC, not AIH. In addition, decreased content of 25(OH)D3 was found in both AIH and PBC. However, levels of 25(OH)D did not differ between the patients and controls, and were independent of disease types and the country. Only one study that met the inclusion criteria reported vitamin B6, B9, B12, and Hcy changes, and found that vitamin B6 and B9 were significantly decreased in patients with PBC, while serum vitamin B12 and Hcy levels were significantly elevated in them. One eligible study each confirmed a reduction in plasma vitamin K1 and 1,25(OH)2D3 in patients with PBC.

CONCLUSION

Most vitamins are deficient in AILD, so appropriate vitamin supplementation should be necessary. Further studies with larger sample sizes are needed to validate these findings.

Deconvolution of the fluorescence spectra measured through a needle probe to assess the functional state of the liver

OBJECTIVES

Currently, one of the most pressing issues for surgeons in the treatment of obstructive jaundice is the ability to assess the functional state of the liver and to detect and determine the degree of liver failure in a timely manner with simple and objective techniques. In this regard, the use of fluorescence spectroscopy method can be considered as one of the ways to improve the informativity of existing diagnostic algorithms in clinical practice and to introduce new diagnostic tools. Thus, the aim of the work was to study in vivo the functional state of liver parenchyma by the method of fluorescence spectroscopy implemented through a needle probe and assess the contribution of the main tissue fluorophores to reveal new diagnostic criteria.

MATERIALS AND METHODS

We compared data from 20 patients diagnosed with obstructive jaundice and 11 patients without this syndrome. Measurements were performed using a fluorescence spectroscopy method at excitation wavelengths of 365 and 450 nm. Data were collected using a 1 mm fiber optic needle probe. The analysis was based on the comparison of the results of deconvolution with the combinations of Gaussian curves reflecting the contribution of the pure fluorophores in the liver tissues.

RESULTS

The results showed a statistically significant increase in the contribution of curves reflecting NAD(P)H fluorescence, bilirubin, and flavins in the group of patients with obstructive jaundice. This and the calculated redox ratio values indicated that the energy metabolism of the hepatocytes may have shifted to glycolysis due to hypoxia. An increase in vitamin A fluorescence was also observed. It may also serve as a marker of liver damage, indicating impaired vitamin A mobilization from the liver due to cholestasis.

CONCLUSIONS

The results obtained reflect changes associated with shifts in the content of the main fluorophores characterizing hepatocyte dysfunction caused by accumulation of bilirubin and bile acids and after disturbance of oxygen utilization. The contributions of NAD(P)H, flavins, and bilirubin as well as vitamin A can be used for further studies as promising diagnostic and prognostic markers for the course of liver failure. Further work will include collecting fluorescence spectroscopy data in patients with different clinical effects of obstructive jaundice on postoperative clinical outcome after biliary decompression.

Lipid droplets, the Holy Grail of hepatic stellate cells: In health and hepatic fibrosis

Lipid droplets (LDs) are distinct morphological markers of hepatic stellate cells (HSCs). They are composed of a core of predominantly retinyl esters and triacylglycerols surrounded by a phospholipid layer; the latter harbors perilipins 2, 3, and 5, which help control LD lipolysis. Electron microscopy distinguishes between Types I and II LDs. Type I LDs are surrounded by acid phosphatase-positive lysosomes, which likely digest LDs. LD count and retinoid concentration are modulated by vitamin A intake. Alcohol consumption depletes hepatic retinoids and HSC LDs, with concomitant transformation of HSCs to fibrogenic myofibroblast-like cells. LD loss and accompanying HSC activation occur in HSC cell culture models. Loss of LDs is a consequence of and not a prerequisite for HSC activation. LDs are endowed with enzymes for synthesizing retinyl esters and triacylglycerols as well as neutral lipases and lysosomal acid lipase for breaking down LDs. HSCs have two distinct metabolic LD pools: an "original" pool in quiescent HSCs and a "new" pool emerging in HSC activation; this two-pool model provides a platform for analyzing LD dynamics in HSC activation. Besides lipolysis, LDs are degraded by lipophagy; however, the coordination between and relative contributions of these two pathways to LD removal are unclear. While induction of autophagy accelerates LD loss in quiescent HSCs and promotes HSC activation, blocking autophagy impairs LD degradation and inhibits HSC activation and fibrosis. This article is a critique of five decades of investigations into the morphology, molecular structure, synthesis, and degradation of LDs associated with HSC activation and fibrosis.

Nutrition Assessment and Management in Patients with Cirrhosis and Cognitive Impairment: A Comprehensive Review of Literature

Hepatic encephalopathy (HE) represents a common complication of liver cirrhosis. Protein-calorie malnutrition is frequently encountered in the cirrhotic patient and its most obvious clinical manifestation is sarcopenia. This condition represents a risk factor for HE occurrence because skeletal muscle acts as an alternative site for ammonium detoxification. Preventive intervention through an adequate assessment of nutritional status should be carried out at early stages of the disease and in a multidisciplinary team using both non-instrumental methods (food diary, anthropometric measurements, blood chemistry tests) and instrumental methods (bioimpedance testing, DEXA, CT, indirect calorimetry, dynamometry). Dietary recommendations for patients with HE do not differ from those for cirrhotic patient without HE. Daily caloric intake in the non-obese patient should be 30–40 Kcal/Kg/day with a protein intake of 1–1.5 g/Kg/day, especially of vegetable origin, through 4–6 meals daily. In patients with HE, it is also essential to monitor electrolyte balance, supplementing any micronutrient deficiencies such as sodium and zinc, as well as vitamin deficiencies because they can cause neurological symptoms similar to those of HE. In light of the critical role of nutritional status, this aspect should not be underestimated and should be included in the diagnostic–therapeutic algorithm of patients with HE.

Retinoic acid regulates erythropoietin production cooperatively with hypoxia-inducible factors in human iPSC-derived erythropoietin-producing cells

Erythropoietin (EPO) is a crucial hormone for erythropoiesis and produced by adult kidneys. Insufficient EPO production in chronic kidney disease (CKD) can cause renal anemia. Although hypoxia-inducible factors (HIFs) are known as a main regulator, the mechanisms of EPO production have not been fully elucidated. In this study, we aimed to examine the roles of retinoic acid (RA) in EPO production using EPO-producing cells derived from human induced pluripotent stem cells (hiPSC-EPO cells) that we previously established. RA augmented EPO production by hiPSC-EPO cells under hypoxia or by treatment with prolyl hydroxylase domain-containing protein (PHD) inhibitors that upregulate HIF signals. Combination treatment with RA and a PHD inhibitor improved renal anemia in vitamin A-depleted CKD model mice. Our findings using hiPSC-EPO cells and CKD model mice may contribute to clarifying the EPO production mechanism and developing efficient therapies for renal anemia.

An Argument for Vitamin D, A, and Zinc Monitoring in Cirrhosis

Malnutrition is prevalent in cirrhosis. Vitamin and mineral deficiencies, including vitamin D, vitamin A, and zinc, are common and have been shown to correlate with survival. Our aim was to review the mechanisms of vitamin D, vitamin A, and zinc deficiencies in cirrhosis and the clinical assessment of affected patients, their outcomes based on the current literature, and management. This is a narrative review including the relevant literature for cirrhosis and vitamin D, vitamin A, and zinc deficiencies. Vitamin D deficiency has important effects in cirrhosis, regardless of the cause of chronic liver disease.These effects include associations with fibrosis and outcomes such as infections, hepatocellular carcinoma, and mortality. Vitamin A deficiency is associated with liver disease progression to cirrhosis and clinical decompensation, including occurrence of ascites or hepatic encephalopathy. Zinc deficiency can lead to hepatic encephalopathy and impaired immune function. Such deficiencies correlate with patient survival and disease severity. Caution should be applied when replacing vitamin D, vitamin A, and zinc to avoid toxicity. Identification and appropriate treatment of vitamin and mineral deficiencies in cirrhosis may reduce specific nutritional and cirrhosis-related adverse events. Routine monitoring of vitamin A, vitamin D and zinc levels in cirrhosis should be considered.

Chronic Complications of Cholestasis: Evaluation and Management

Patients with primary biliary cholangitis (PBC) are at risk for various harmful consequences of chronic cholestasis. These include fat-soluble vitamin deficiency, even in the setting of macronutrient sufficiency, as well as metabolic bone disease, including osteoporosis with fractures. Hyperlipidemia is often present and less commonly associated with risk of cardiovascular event; however, the long-term effect of new emerging therapies for PBC remains to be determined. Patients with PBC also have infrequent but notable risk of portal hypertension despite early-stage disease. This review discusses the background, evaluation, and practical management of these complications of chronic cholestasis.

Vitamin A deficiency in chronic cholestatic liver disease: Is vitamin A therapy beneficial?

Chronic cholestatic diseases are progressive diseases of the biliary tract that cause hepatic fibrosis and ultimately lead to liver failure. Liver transplantation is the sole curative option currently available, and because of high morbidity and mortality rates of these diseases, new therapeutic approaches are needed. Vitamin A is a nutrient essential for health as it regulates many processes, including epithelial growth and immunological processes. Vitamin A is primarily stored in hepatic stellate cells, and during liver injury, through an unknown mechanism, these cells lose vitamin A and convert into collagen-producing myofibroblasts, which contributes to hepatic fibrosis. Vitamin A deficiencies in chronic cholestatic diseases have been frequently reported, and therefore, retinoid metabolism has attracted a lot of attention. Retinoids have been shown to attenuate or even prevent hepatic fibrosis, and to regulate hepatic immunological response to cholestatic injury in different rodent models of chronic cholestasis. Recently, their potential as therapeutic drugs in primary sclerosing cholangitis patients was analyzed. The aim of this review is to summarize the existing knowledge and hypotheses about vitamin A role and the disease progression in cholestatic liver disease.

Nutrition in Chronic Liver Disease

Protein-calorie malnutrition is a transversal condition to all stages of chronic liver disease. Early recognition of micro or macronutrient deficiencies is essential, because the use of nutritional supplements reduces the risk of complications. The diet of patients with chronic liver disease is based on a standard diet with supplements addition as necessary. Restrictions may be harmful and should be individualized. Treatment management should aim to maintain an adequate protein and caloric intake and to correct nutrient deficiencies. The large majority of patients with grade I/II hepatic encephalopathy can tolerate a regular diet. Protein restriction can aggravate malnutrition and is not recommended, except in cases of hepatic encephalopathy unresponsive to optimized therapy.

Histologic abnormalities are common in protocol liver allograft biopsies from patients with normal liver function tests

The utility of protocol liver allograft biopsies remains controversial, particularly in patients with normal liver function tests (LFTs). However, histologic evaluation of these biopsies provides an opportunity to examine the types and severity of liver diseases that can occur in livers with normal clinical and biochemical function. We studied 165 protocol allograft biopsies taken from 100 liver transplant patients at the time of normal LFTs and normal clinical function at 3 to 8 months (n=36), 1 year (n=52), 2 to 3 years (n=54), and 4 to 5 years (n=23). Biopsies were classified as normal, minimal changes (eg, nonaggressive portal or lobular mononuclear inflammation, steatosis <10%), fatty liver disease, recurrent primary liver disease, and transplant-related disease (portal-based rejection or central venulitis, an inflammatory pattern that encompasses perivenular hepatocyte dropout, mononuclear inflammation, pigment-laden macrophages, and variable zone 3 fibrosis). Among these 100 patients, a total of 394 protocol biopsies were performed, and 165 (42%) were taken at the time of normal LFTs and normal clinical function. One hundred twenty-one (73%) were normal or showed minimal/nonspecific changes. Forty-four (27%) showed histologic abnormalities that included fatty liver disease (n=19, nonalcoholic in 18 cases; 13 with mild steatosis, 6 with moderate steatosis, 7 with grade 1/3 steatohepatitic activity, and 2 with stage 1/4 steatohepatitic fibrosis), recurrent primary biliary cirrhosis (n=9; all stage 1/4), recurrent hepatitis C infection (n=6; grade 0/4 in 1, grade 1/4 in 5, stage 0/4 in 4, stage 1/4 in 1, and stage 2/4 in 1), recurrent sarcoidosis (n=1), Ito cell hyperplasia (n=4; marked in 2 and mild in 2), central venulitis (n=10; 5 with mild zone 3 fibrosis or central vein obliteration and 1 with central-portal bridging fibrosis), and mild acute portal rejection (n=2). We judged the histologic changes to be of clinical significance in 19 (11.5%) cases. These results indicate that even at the time of normal clinical and laboratory function, a significant fraction of protocol allograft biopsies harbor histologic (27%) and clinically significant (11.5%) abnormalities. These most commonly include fatty liver disease, low-grade/low-stage recurrent hepatitis C and primary biliary cirrhosis, and central venulitis (including some cases with subsequent fibrosis progression). The data support performance of protocol biopsies to assess allograft status, and provide insight into the types and severity of liver diseases that can smolder in transplanted (and by extension, probably also in native) livers with apparent normal function.

Novel serum biomarker candidates for liver fibrosis in hepatitis C patients

BACKGROUND

Liver biopsy is currently the gold standard for assessing liver fibrosis, and no reliable noninvasive diagnostic approach is available. Therefore a suitable serologic biomarker of liver fibrosis is urgently needed.

METHODS

We used a proteomics method based on 2-dimensional gel electrophoresis to identify potential fibrosis biomarkers. Serum samples from patients with varying degrees of hepatic scarring induced by infection with the hepatitis C virus (HCV) were analyzed and compared with serum from healthy controls.

RESULTS

We observed the most prominent differences when we compared serum samples from cirrhotic patients with healthy control serum. Inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4) fragments, alpha1 antichymotrypsin, apolipoprotein L1 (Apo L1), prealbumin, albumin, paraoxonase/arylesterase 1, and zinc-alpha2-glycoprotein were decreased in cirrhotic serum, whereas CD5 antigen-like protein (CD5L) and beta2 glycoprotein I (beta2GPI) were increased. In general, alpha2 macroglobulin (a2M) and immunoglobulin components increased with hepatic fibrosis, whereas haptoglobin and complement components (C3, C4, and factor H-related protein 1) decreased. Novel proteins associated with HCV-induced fibrosis included ITIH4 fragments, complement factor H-related protein 1, CD5L, Apo L1, beta2GPI, and thioester-cleaved products of a2M.

CONCLUSIONS

Assessment of hepatic scarring may be performed with a combination of these novel fibrosis biomarkers, thus eliminating the need for liver biopsy. Further evaluation of these candidate markers needs to be performed in larger patient populations. Diagnosis of fibrosis during early stages will allow early treatment, thereby preventing fibrosis progression.

Total Parenteral Nutrition: Challenges and Practice in the Cirrhotic Patient

Patients with cirrhosis develop metabolic derangements of protein, carbohydrate, and lipid metabolism. Malnutrition is commonplace and is associated with morbidity and mortality. Specific nutrient deficiencies may occur and enteral or parenteral nutritional support may improve outcome in appropriately selected patients. Parenteral nutrition itself has been associated with hepatic dysfunction, although the preponderance of evidence suggests that hepatic dysfunction is more a function of the underlying disorder and malabsorption. Intravenously infused organic nutrients may be metabolized differently than the same nutrient consumed enterally. The pathophysiology of total parenteral nutrition-associated liver disease is discussed as well as potential management options.

Nutritional support in patients with chronic liver disease

Malnutrition is highly prevalent among patients with chronic liver disease and is nearly universal among patients awaiting liver transplantation. Malnutrition in patients with cirrhosis leads to increased morbidity and mortality rates. Furthermore, patients who are severely malnourished before transplant surgery have a higher rate of complications and a decreased overall survival rate after liver transplantation. In light of the high incidence of malnutrition among patients with chronic liver disease and the complications that result from malnutrition in these patients, it is essential to assess the nutritional status of all patients with liver disease, and to initiate treatment as indicated. This review addresses the etiologies of malnutrition, methods used to assess nutritional status, and appropriate treatment strategies.

Increased urinary excretion of 8-iso-prostaglandin F2alpha in patients with HFE-related hemochromatosis: a case-control study

The hypothesis according to which iron overload could be harmful has been extensively and controversially discussed in the literature. One underlying pathological mechanism may be elevated oxidative stress. Thus, we studied the correlation between hemochromatosis and an established marker of oxidative stress, 8-iso-prostaglandin F2alpha (8-iso-PGF2alpha, iPF2alpha-III, 15-F2t-IsoP). We enrolled 21 patients with hemochromatosis, positive for the homozygous C282Y mutation in the HFE gene, and 21 healthy controls frequency-matched by age and gender in a case-control study design. The objective was to show that iron overload in HFE-related hemochromatosis is associated with increased oxidative stress assessed through 8-iso-PGF(2alpha) urinary excretion, and that oxidative stress is impacted by iron-removal treatment (phlebotomy). Study parameters were transferrin saturation, 8-iso-PGF(2alpha) urine excretion, transferrin, ferritin, serum iron, and vitamins A and E for all participants. Iron concentration in the liver and non-transferrin-bound iron were measured in patients only. We found a significant difference in 8-iso-PGF2alpha in patients (245 [interquartile range 157-348] pg/mg creatinine) compared with controls (128 [106-191] pg/mg creatinine, P = 0.002). Vitamin A was significantly reduced in cases (0.34 [0.25-1.83] microg/ml compared to 3.00 [2.11-3.39] microg/ml, P < 0.001), while vitamin E did not show a significant difference in cases (14.7 [11.5-18.1] microg/ml) compared with controls (14.9 [13.1-19.2] microg/ml, P = 0.52). After phlebotomy treatment and normalization of the iron parameters in the hemochromatosis group, serum vitamin A levels were significantly increased (1.36 [1.08-1.97] microg/ml, P = 0.035 vs. baseline, P < 0.001 vs. controls) and 8-iso-PGF2alpha urinary excretion was lowered to control levels (146 [117-198] pg/mg creatinine, P = 0.38 vs. controls). In our study, HFE-related hemochromatosis was associated with increased oxidative stress and hypovitaminemia A in C282Y homozygotes. The increased oxidative stress was reversible by normalization of the iron load by phlebotomy. Thus, phlebotomy is an effective and adequate means for reducing oxidative stress in these patients.

Retinoid metabolism during development of liver cirrhosis

The changes in retinoid metabolism have been documented in liver cirrhosis. However, the dynamic alterations in levels of this vitamin between circulation and liver during development of the liver cirrhosis are not well understood. The aim of this study was to measure retinoids in the liver and circulation in parallel, during and after development of cirrhosis induced by carbon tetrachloride and thioacetamide. Retinoid levels were measured by HPLC. A decrease in retinaldehyde and total retinol, together with an increase in retinoic acid was evident in liver from both carbon tetrachloride or thioacetamide treated rats within a month after initiation of treatment. Activity of enzymes involved in retinoid metabolism such as retinaldehyde oxidase, retinaldehyde dehydrogenase, and retinaldehyde reductase were decreased in the liver. In parallel, levels of retinol and retinaldehyde in the serum were increased while retinoic acid was decreased. This study indicates that during development of cirrhosis, there is reciprocal transfer of retinoid metabolites between the circulation and the liver.

Management of osteoporosis, fat-soluble vitamin deficiencies, and hyperlipidemia in primary biliary cirrhosis

Osteoporosis is several times more common in patients with PBC compared with the general population. Maintaining adequate intake of calcium and vitamin D is important for prevention of bone loss. The use of bisphosphonates or vitamin K to improve bone mineral density in osteopenic patients seems promising and needs to be further evaluated. Patients with PBC may develop fat-soluble vitamin deficiencies, especially vitamins A and D; serum levels should be investigated in patients considered at risk with the aim of recommending appropriate replacement therapy. Finally, hyperlipidemia in PBC does not seem to be associated with an increased risk of atherogenesis. New therapies in this patient population are currently under investigation.

Oxidant stress is a significant feature of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic cholestatic disorder characterised by an immunological, and often granulomatous, attack on bile ducts leading to fibrosis, cirrhosis, liver failure and death. Animal and human studies suggest that oxidant stress plays a key role in progression of other liver diseases, but no comprehensive investigation has been performed previously in PBC. A wide range of lipid peroxidation and antioxidant markers were measured in the blood and urine of 41 patients with histologically confirmed PBC. Lipid peroxidation markers were significantly elevated [plasma and urinary 8-isoprostane, P<0.001; plasma malondialdehyde (MDA), P=0.007] compared to age- and sex-matched controls. The most striking antioxidant depletion occurred with plasma total glutathione where levels were significantly reduced (30% of controls). Total serum antioxidant levels were decreased (P=0.013) and serum selenium and vitamin A were also lower (both P<0.001); vitamins C and E were normal. Most patients had early disease biochemically and were Child-Pugh grade A. Urinary 8-isoprostane correlated positively with Ludwig stage and markers of hepatic injury and cholestasis. This study clearly demonstrates that oxidant stress, as reflected in a comprehensive spectrum of lipid peroxidation and antioxidant markers, is a significant feature of early-stage PBC.

Possible role of endogenous retinoid (Vitamin A) toxicity in the pathophysiology of primary biliary cirrhosis

Primary biliary cirrhosis (PBC) is a chronic, cholestatic disease of unknown etiology commonly affecting women. It is characterized by progressive destruction of the small intrahepatic bile ducts and portal inflammation, leading to fibrosis and cirrhosis. The major signs and symptoms of PBC, which include pruritus, lethargy, the sicca syndrome, and osteoporosis, closely resemble the manifestations of hypervitaminosis A. Based on a review of the literature and other observations connecting PBC with retinoid metabolism (vitamin A and its derivatives), the hypothesis is proposed that exposure to excess endogenous retinoids contributes to the pathogenesis of PBC and may be to the cause of some of the signs and symptoms associated with the disease.

Plasma antioxidant levels in chronic cholestatic liver diseases

BACKGROUND

[corrected] A predictable consequence of cholestasis is malabsorption of fat-soluble factors, (vitamins A, D, E, K) and other free radical scavengers, such as carotenoids. It has been suggested that oxygen-derived free radicals may be involved in the pathogenesis of chronic liver damage.

AIMS

(i) To evaluate retinol, alpha-tocopherol and carotenoid plasma levels in two groups of patients with chronic cholestatic liver disease (primary biliary cirrhosis and primary sclerosing cholangitis); (ii) to compare the respective plasma levels with those of the general population; (iii) to correlate the plasma levels with disease severity.

METHODS

A total of 105 patients with chronic cholestasis were included in the study: 86 with primary biliary cirrhosis (81 female, five male, mean age 55.5 +/- 11 years), 19 with primary sclerosing cholangitis (seven female, 12 male, mean age 35 +/- 11 years; six patients had associated inflammatory bowel disease); 105 sex- and age-matched subjects from the general population in the same geographical area (88 female, 17 male, mean age 51.3.5 +/- 10 years) served as controls. Carotenoids (lutein zeaxanthin, lycopene, beta-carotene, alpha-carotene, beta-cryptoxanthin), retinol and alpha-tocopherol were assayed by high-pressure liquid chromatography. A food frequency questionnaire was administered to each subject to evaluate the quality and the quantity of dietary compounds. Data were processed by analysis of variance and linear regression analysis, as appropriate.

RESULTS

Both primary biliary cirrhosis and primary sclerosing cholangitis patients had significantly lower levels of retinol, alpha-tocopherol, total carotenoids, lutein, zeaxanthin, lycopene, alpha- and beta-carotene than controls (P < 0.0001). Among the cholestatic patients, no significant difference in the concentration of antioxidants was observed between primary biliary cirrhosis and primary sclerosing cholangitis subjects. Anti-oxidant plasma levels were not affected by the severity of the histological stage in primary biliary cirrhosis, but a negative correlation was found between total carotenoids and both alkaline phosphatase (ALP) and gammaglutamyl transpeptidase (GGT) (P < 0.013 and P < 0.018, respectively). Within the primary sclerosing cholangitis group, no correlation was found between total carotenoids and cholestatic enzymes. Nutritional intake in cholestatic patients was comparable to controls, including fruit and vegetable intake.

CONCLUSIONS

Although no clinical sign of deficiency is evident, plasma levels of antioxidants are low in cholestatic patients even in early stages of the disease. This is probably due to malabsorption of fat-soluble vitamins, as well as other mechanisms of hepatic release, suggesting the need for dietary supplementation.

Dark adaptation in early primary biliary cirrhosis

BACKGROUND

The role of vitamin A in early primary biliary cirrhosis (PBC) remains uncertain.

METHODS

We assessed dark adaptation and assayed vitamin-A-related compounds in 10 patients with early PBC and a group of age- and sex-matched controls.

RESULTS

In patients compared with controls: (i) mean final light threshold value was 11.8% greater (p < 0.004), (ii) time taken to see the first light stimulus was longer (2.8 +/- 0.6 vs 1.4 +/- 0.2 min, mean +/- SEM; p < 0.03) and (iii) sensitivity to light stimuli was impaired after 6 min in the dark (p < 0.03). Three patients had an abnormal final light threshold despite receiving regular vitamin A; two had a low serum vitamin A. Raised serum bilirubin and increased age were the most important determinants of impaired dark adaptation.

CONCLUSIONS

Patients with early PBC have modestly impaired dark adaptation, despite standard vitamin A supplementation, although these changes may not have a significant effect on visual function. Vitamin A supplementation should be recommended for older patients with jaundice, but its effect should be carefully monitored.

The hepatic stellate (Ito) cell: its role in human liver disease

The hepatic stellate (Ito) cell lies within the space of Disse and has a variety of functions. Stellate cells store vitamin A in characteristic lipid droplets. In the normal human liver, the cells can be identified by the presence of these lipid droplets; in addition, many stellate cells in the normal liver express alpha-smooth muscle actin. In acute liver injury, there is an expansion of the stellate cell population with increased alpha-smooth muscle actin expression; stellate cells appear to play a role in extracellular matrix remodelling after recovery from injury. In chronic liver injury, the stellate cell differentiates into a myofibroblast-like cell with marked expression of alpha-smooth muscle actin and occasional expression of desmin. Myofibroblast-like cells have a high fibrogenic capacity in the chronically diseased liver and are also involved in matrix degradation. In vitamin A intoxication, hypertrophy and proliferation of the stellate and myofibroblast-like cells may lead to non-cirrhotic portal hypertension, fibrosis and cirrhosis. In liver tumours, myofibroblast-like cells are involved in the capsule formation around the tumour and in the production of extracellular matrix within it. The transition of stellate cells into myofibroblast-like cells is regulated by an intricate network of intercellular communication between stellate cells and activated Kupffer cells, damaged hepatocytes, platelets, endothelial and inflammatory cells, involving cytokines and nonpeptide mediators such as reactive oxygen species, eicosanoids and acetaldehyde. The findings suggest that the stellate cell plays an active role in a number of human liver diseases, with a particular reactivity pattern in fibrotic liver disorders.

Influence of orthotopic liver transplantation on serum vitamin A levels in patients with chronic liver disease

BACKGROUND

Low serum vitamin A levels are observed in many liver diseases, such as primary biliary cirrhosis (PBC) and alcoholic liver disease. The aim of this study was to investigate serum vitamin A in patients with advanced liver diseases before and after orthotopic liver transplantation (OLT).

METHODS

Serum vitamin A (retinol) concentrations were investigated in 54 patients before (OLT) and in 21 patients 1, 2, 3, and 4 weeks and 2 and 3 months after OLT. Ten healthy subjects and 19 patients with inflammatory bowel disease (IBD) served as control groups.

RESULTS

The mean serum retinol concentration before OLT was 0.64 +/- 0.1 mumol/l in patients with alcoholic and postnecrotic cirrhosis (n = 24), 1.06 +/- 0.48 mumol/l in patients with PBC (n = 14), 0.96 +/- 0.64 mumol/l in sclerosing cholangitis (n = 7), and 1.02 +/- 0.73 mumol/l in liver cancer (n = 9). These results were significantly lower than in healthy controls (2.34 +/- 0.54 mumol/l) and patients with IBD (2.7 +/- 0.74 mumol/l) (p < 0.001).

CONCLUSIONS

After OLT, serum retinol levels increased significantly already after 1 week (1.4 +/- 0.1 mumol/l) (p < 0.001), normalized after 2 weeks (2.2 +/- 0.4 mumol/l), and remained normal during the observation.

Vitamin A status of alcoholics upon admission and after two weeks of hospitalization

The purpose of this study was to determine the vitamin A status of alcoholics upon admission and after a brief in-patient stay. Fasting blood was drawn from 28 randomly selected subjects who were presumed to represent a wide range of liver disease severity. Admission laboratory tests revealed hypozincemia in 14.8% of subjects, while serum retinol and retinol-binding protein (RBP) were depressed below normal range in 15 (57.1%) and 7 (25%) of the subjects, respectively. Significant linear correlations were found between serum retinol and RBP (r = 0.90, p < or = 0.0001), serum retinol and albumin (r = 0.76, p < or = 0.0001), serum retinol and serum zinc (r = 0.56, p < or = 0.0003), and serum retinol and serum triglycerides (r = 0.42, p < or = 0.006). All subjects with elevated serum bilirubin levels demonstrated depressed serum retinol levels. However, elevated molar ratios of retinol to RBP suggest that the carrying capacity of RBP was at times exceeded, even with low serum retinol levels. Follow-up of 12 subject after 2 weeks of hospitalization revealed significant individual changes in blood chemistry, but no general trends. Although this study emphasizes the need for individual evaluation and treatment, elevated bilirubin levels may be indicative of low serum retinol levels in the alcoholic. Caution in levels of vitamin A therapy in these cases is advised, and consideration should instead be given to beta-carotene supplementation.

Lipid-laden perisinusoidal cells in patients with acquired immunodeficiency syndrome

Liver biopsies were taken from ten AIDS patients. Liver architecture was normal in all patients. On 1-micron-thick sections stained with toluidine blue, all ten cases showed lipid overload of perisinusoidal cells (1 massive, 5 moderate and 4 mild) compared to 2/8 in control patients, who had mild lipid overload. Other sinusoidal abnormalities such as hypertrophy of Kupffer cells and inclusions in endothelial cells were also noticed. Some hepatocytes presented evidence of cellular damage. Perisinusoidal cell lipid overload was not associated with hypervitaminosis A. We hypothesize that the abnormal accumulation of lipids in perisinusoidal cells (non-induced by hypervitaminosis A) in patients with AIDS could be due to defective transport of vitamin A from perisinusoidal cells to hepatocytes, and/or from hepatocytes to blood. The cause of the defect is unknown. Since lipid overload occurs in many and diverse conditions (diabetes, cholestasis, primary biliary cirrhosis, etc.), it seems reasonable to propose that the defect is non-specific and limited to functional or structural damage of the liver whether induced by drugs, liver or systemic diseases.

Vitamin A status in different stages of schistosomal cases and the effectiveness of oral vitamin A therapy

Thirty bilharzial patients were studied for their vitamin A status. Of the patients, 30% were found to have low-fasting serum retinol level below the acceptable level of 20 micrograms/dl and one-third were presented with night blindness. Oral vitamin A therapy was effective in correcting the vitamin A deficiency among this group of patients.

Fine structure of hepatic sinusoids and sinusoidal cells in disease

Liver sinusoids are special capillaries that are limited by fenestrated endothelial cells, without a genuine basement membrane, surrounded by perisinusoidal cells storing vitamin A, and harbouring Kupffer cells and pit cells, resident macrophages, and large granular lymphocytes, respectively. Each nonparenchymal cell and parenchymal cell of the liver interacts with all others and with the extracellular matrix. Therefore, the functional ability of each cell is constantly being modified by the metabolic activity of the others. Human liver biopsies (132), needle or surgical, perfusion-fixed with glutaraldehyde and processed for transmission electron microscopy (TEM), and occasionally for scanning electron microscopy (SEM), were examined. The study included liver diseases (such as alcoholic liver diseases, benign and malignant liver tumors, cholestasis of various origins, fulminant hepatitis, acute rejection after orthotopic liver transplantation, Budd-Chiari syndrome), as well as general or extrahepatic diseases (such as diabetes, hemochromatosis, hypervitaminosis A, various hematological disorders), and normal controls. Ultrastructural abnormalities are described and illustrated under two different headings: 1) elementary lesions of sinusoidal cells (endothelial, Kupffer, perisinusoidal and pit cells), nonsinusoidal cells (in the space of Disse and/or in the lumen), the extracellular matrix; and 2) the major pathological entities including perisinusoidal fibrosis, capillarization of sinusoids, sinusoidal dilatation, and peliosis. In the discussion, an overview of the major abnormalities reported in the literature is presented, and some specific questions regarding 1) perisinusoidal fibrosis in liver with normal histology, 2) the overload of perisinusoidal cells with lipids in non-hypervitaminosis A intoxication and 3) the etiological relationship of sinusoidal dilatation, peliosis, perisinusoidal fibrosis, or sinusoidal tumors with drugs and toxic compounds are discussed. In the event that lesions are not specific to any diagnosis, the knowledge of the ultrastructure of sinusoids is extremely useful from the perspective of the liver as an ecosystem.

Primary biliary cirrhosis

Primary biliary cirrhosis is a chronic liver disease of unknown etiology characterized by slowly progressive intrahepatic cholestasis due to an inflammatory destruction of small intrahepatic bile ducts. The clinical course of PBC is variable ranging from a few years in rapidly progressive cases to a normal life-expectancy in a proportion of asymptomatic cases. The typical patient is a middle-aged woman who may present with pruritus, increasing pigmentation of the skin, and eventually jaundice. The level of serum alkaline phosphatase is almost invariably elevated, serum mitochondrial antibodies are present in more than 90 per cent, and an elevated serum IgM is usually present. PBC is associated with many immunologic abnormalities and appears to be a classic autoimmune disease. Some of the immune defects may be epiphenomena; others such as a marked defect in suppressor T cell function seem to be related to the pathogenesis of the disease. All drug therapy that is aimed at slowing the disease process is experimental. A place for immunosuppressive drugs in the management of PBC would be anticipated. However, no drug has to date been definitively shown to have a beneficial effect on the disease. Currently, the main treatments used are aimed at preventing or correcting the complications of intractable cholestasis. Patients with PBC and evidence of hepatic decompensation and/or poor quality of life make good candidates for liver transplantation. The current aim of therapy is to find an effective regime of immunosuppression that will make hepatic transplantation redundant for this disease.

Fat-soluble vitamin nutriture in primary biliary cirrhosis

We measured serum levels of vitamins A, E, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D, as well as levels of abnormal (des-gamma-carboxy) prothrombin, in 52 patients with primary biliary cirrhosis. Decreased serum levels of retinol (vitamin A) and 25-hydroxyvitamin D and elevated levels of abnormal prothrombin were common in these patients and correlated with the histologic stage of the disease and with the clinical severity of disease as judged by elevated serum bilirubin levels and decreased serum albumin levels. The increased levels of abnormal prothrombin were due primarily to vitamin K deficiency but also, in part, to the severity of the liver disease itself. Vitamin E deficiency was rare. Only 1 patient had clinical manifestations of fat-soluble vitamin deficiency, night blindness, and gastrointestinal bleeding related to a marked prolongation of the prothrombin time. Deficiencies of fat-soluble vitamins are most likely to be present in jaundiced patients with long-standing, severe cholestasis. We suggest that fat-soluble vitamin status be determined in all patients with primary biliary cirrhosis by appropriate blood tests and that vitamin supplements be given only to those patients who require them.