Cerebrotendinous xanthomatosis (CTX), sterol 27-hydroxylase (CYP27A1) deficiency, is associated with markedly reduced chenodeoxycholic acid (CDCA), the most powerful activating ligand for farnesoid X ...receptor (FXR). We investigated the effects of reduced CDCA on FXR target genes in humans. Liver specimens from an untreated CTX patient and 10 control subjects were studied. In the patient, hepatic CDCA concentration was markedly reduced but the bile alcohol level exceeded CDCA levels in control subjects (73.5 vs. 37.8 ± 6.2 nmol/g liver). Cholesterol 7α-hydroxylase (CYP7A1) and Na+/taurocholate-cotransporting polypeptide (NTCP) were upregulated 84- and 8-fold, respectively. However, small heterodimer partner (SHP) and bile salt export pump were normally expressed. Marked CYP7A1 induction with normal SHP expression was not explained by the regulation of liver X receptor α (LXRα) or pregnane X receptor. However, another nuclear receptor, hepatocyte nuclear factor 4α (HNF4α), was induced 2.9-fold in CTX, which was associated with enhanced mRNA levels of HNF4α target genes, CYP7A1, 7α-hydroxy-4-cholesten-3-one 12α-hydroxylase, CYP27A1, and NTCP.
In conclusion, the coordinate regulation of FXR target genes was lost in CTX. The mechanism of the disruption may be explained by a normally stimulated FXR pathway attributable to markedly increased bile alcohols with activation of HNF4α caused by reduced bile acids in CTX liver.
Plasma 7α-hydroxy-4-cholesten-3-one has been used as an index of hepatic bile acid synthesis. The aim of the current study was to ascertain whether the level of this oxysterol reflects hepatic ...cholesterol 7α-hydroxylase activity when plasma cholesterol concentrations are markedly changed. In addition, the relationship of hepatic sterol 27-hydroxylase activity with plasma concentrations of 27-hydroxycholesterol and 3β-hydroxy-5-cholestenoic acid was studied. We used New Zealand white rabbits fed 2% cholesterol for 5 or 10 days and/or constructed bile fistula. Feeding cholesterol markedly increased and bile drainage reduced plasma cholesterol concentrations. Initially, in these models there was no correlation between plasma 7α-hydroxy-4-cholesten-3-one concentrations and hepatic cholesterol 7α-hydroxylase activities (
r = −0.24, n = 10). Cholesterol feeding was associated with downregulated 7α-hydroxylase activities, while plasma 7α-hydroxy-4-cholesten-3-one concentrations were elevated in the presence of increased plasma cholesterol levels. However, this discrepancy was overcome and significant correlation was observed (
r = 0.73,
P < .05, n = 10) by expressing 7α-hydroxy-4-cholesten-3-one levels relative to cholesterol. In contrast, hepatic sterol 27-hydroxylase activities were not significantly correlated with plasma absolute (
r = 0.23, difference not significant NS, n = 10) nor cholesterol-related levels of 27-hydroxycholesterol (
r = −0.13, NS, n = 10), or 3β-hydroxy-5-cholestenoic acid concentrations (
r = 0.30, NS, n = 10). In conclusion, plasma 7α-hydroxy-4-cholesten-3-one concentrations reflected hepatic cholesterol 7α-hydroxylase activities when the sterol levels were adjusted to plasma cholesterol concentrations in rabbits with hypercholesterolemia. The results suggest that plasma 7α-hydroxy-4-cholesten-3-one relative to cholesterol is a better marker for hepatic cholesterol 7α-hydroxylase activity than the absolute concentration when hypercholesterolemia is present. In contrast, 27-hydroxycholesterol and 3β-hydroxy-5-cholestenoic acid levels in plasma did not reflect hepatic sterol 27-hydroxylase activities even if the levels were adjusted to plasma cholesterol concentrations.
To determine the frequency and degree of milk aspiration in infant death cases, immunohistochemical examinations were performed on lung sections from 41 sudden death cases and 64 in-hospital death ...cases using anti-human α-lactalbumin antibody. Milk aspiration to some degree was detected in more than half of the sudden death cases and in about one-third of the in-hospital death cases. A semi-quantitative examination of the amount of aspirated milk was subsequently performed in the positive cases. The amount of aspirated milk in the sudden death cases was significantly higher than that in the in-hospital death cases. The frequency distribution of the amount of aspirated milk was similar in shape in both groups. In most cases, a very small amount of aspirated milk was detected. The aspirated milk was assumed to be a result of occasional gastroesophageal reflux or cardiopulmonary resuscitation. However, in five cases, much larger amounts of aspirated milk were found. In these cases, milk aspiration may have been an important part of the cause of death. We concluded that slight milk aspiration is not rare in infant death cases, and that in a few cases, the aspiration is lethal. An immunohistochemical screening test is available to perform a postmortem diagnosis in these cases.
The aim of this study was to explore the regulation of serum cholic acid (CA)/chenodeoxycholic acid (CDCA) ratio in cholestatic hamster induced by ligation of the common bile duct for 48 h. The serum ...concentration of total bile acids and CA/CDCA ratio were significantly elevated, and the serum proportion of unconjugated bile acids to total bile acids was reduced in the cholestatic hamster similar to that in patients with obstructive jaundice. The hepatic CA/CDCA ratio increased from 3.6 to 11.0 (
P<0.05) along with a 2.9-fold elevation in CA concentration (
P<0.05) while the CDCA level remained unchanged. The hepatic mRNA and protein level as well as microsomal activity of the cholesterol 7α-hydroxylase, 7α-hydroxy-4-cholesten-3-one 12α-hydroxylase and 5β-cholestane-3α,7α,12α-triol 25-hydroxylase were not significantly affected in cholestatic hamsters. In contrast, the mitochondrial activity and enzyme mass of the sterol 27-hydroxylase were significantly reduced, while its mRNA levels remained normal in bile duct-ligated hamster. In conclusion, bile acid biosynthetic pathway via mitochondrial sterol 27-hydroxylase was preferentially inhibited in bile duct-ligated hamsters. The suppression of CYP27A1 is, at least in part, responsible for the relative decreased production of CDCA and increased CA/CDCA ratio in the liver, bile and serum of cholestatic hamsters.
We have previously reported that oral taurine administration reduced the frequency of painful muscle cramps in patients with liver cirrhosis, and that skeletal muscle taurine concentration was ...significantly decreased after exercise. The aim of this study was to examine taurine concentration in various tissues of a liver damaged with fibrosis (LD) in a rat model before and after exercise.
Rats were divided into normal (NML) and LD groups. The LD group received CCl(4) injection for 10 weeks. Thereafter, both groups were divided into control (NML/CTL, LD/CTL) and exercise (NML/EX, LD/EX) groups, respectively. The rats in the EX groups were subjected to treadmill running. Plasma, liver, brain, heart, and skeletal muscle taurine concentration, as well as plasma and liver lipid peroxidase (LPO) concentration, were measured.
The liver, brain, and skeletal muscle taurine concentration in the LD groups was significantly decreased compared to that in the respective NML groups. Furthermore, the taurine concentration in the heart and skeletal muscles in the LD/CTL group was significantly decreased post exercise. The respective plasma and liver LPO concentration in the LD groups was significantly increased compared to that in the corresponding NML group. Moreover, plasma LPO concentration in the LD/EX group was significantly higher than in the LD/CTL group.
Tissue taurine concentration, particularly in skeletal muscle, was significantly decreased in the LD model rats induced by CCl(4) administration, and furthermore, the significantly decreased concentration, except for liver, was aggravated by exercise, even though at lower intensity.
We examined the changes in the levels of soluble major histocompatibility antigen complex (MHC) class I antigens in the serum under a lethal or nonlethal state of graft-versus-host-disease (GVHD) ...induced by injecting various doses of PVG rat splenic lymphocytes into (DA × PVG)F
1 rats. All rats receiving 4 × 10
8 lymphocytes (lethal dose) died on day 20–36 showing typical features of GVHD, while the injection of 4 × 10
7 cells (nonlethal dose) induced no sign of GVHD. When rats were inoculated with a nonlethal dose of lymphocytes prior to the injection of a lethal dose, all rats survived with or without showing transient GVHD. Preceding the onset of GVHD the levels of soluble class I antigens increased significantly to 1094 ± 487 ng/ml (mean ± SD,
n = 4) from 3 days after the injection of a lethal dose to the time of death, whilst the levels in the nonlethal dose group remained unchanged. Rats with transient GVHD in the preinoculated group showed the increase of soluble class I antigens to the same extent as rats with lethal GVHD, suggesting that GVHD was systematically ongoing. The levels of soluble class I antigens also correlated with the severity of GVHD as judged by daily observation and histological studies. Rats receiving a lethal dose showed destructive alteration of spleen structure and cellular infiltration in the portal area of the liver before the animals started to show signs of GVHD, whereas rats in the nonlethal dose group exhibited no marked change. These data suggest the possibility of serum soluble class I antigens being not only a diagnostic but also a prognostic marker for GVHD.
The distribution of pulmonary neuroendocrine cells (PNEC) was analyzed immunohistochemically in 14 victims of sudden infant death syndrome (SIDS), and 10 cases of infant death unrelated to SIDS, ...excluding congenital heart disease. Lung tissue sections were immunostained with antibodies against chromogranin A (CGA), calcitonin (CT) and gastrin-releasing peptide (GRP). CT/GRP immunoreactivity decreased in older infants of each group, while CGA immunoreactivity showed almost no decrease. Serial section analysis showed some PNEC produced CGA, CT and GRP. However, CGA-immunoreactive PNEC sometimes lacked of CT/GRP immunoreactivity. The difference of PNEC distribution between SIDS and the control cases could not be verified. To date, there have been no studies reported of PNEC distribution in infants by using CGA expression. CGA is considered to be the most useful marker for detecting PNEC in infant lung. Our findings suggest that substances produced by PNEC changed with postnatal development both in SIDS and the control group. This result may be one clue to clarifying the development and function of small airways in infants, allowing further progress in SIDS research.
Background/Aims: The injection of parental CD4
+ T cells into major histocompatibility complex (MHC) class II disparate F
1 hybrid mice induced an autoimmune graft-versus-host reaction (GVHR) which ...is analogous to autoimmune liver diseases. The interaction of adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1) and very late antigen-4 (VLA-4) has been known to be profoundly involved in the trafficking of lymphocytes into the inflammatory tissues. The aim of this study was to clarify the role of VLA-4 or VCAM-1 in the development of GVHR-induced hepatic lesions in our model.
Methods: B6 T spleen cells were injected into (B6.
C-H-2
bm12
×B6) F
1 mice intravenously. Anti-VLA-4 mAbs and/or anti-VCAM-1 mAbs were injected intraperitoneally at a dose of 2.5 mg/kg of each mAbs per body weight of mouse. We examined the changes in GVHR-induced hepatic lesions, serum levels of antimitochondrial antibodies (AMA) and cytokine mRNA expressions of liver-infiltrating lymphocytes using H.E. and immunohistochemical staining, enzyme-linked immunosorbent assay (ELISA), and reverse transcription-poly-merase chain reaction (RT-PCR), respectively.
Results: Hepatic lesions of anti-VLA-4 mAbs-treated mice were inhibited compared with those of GVHR mice. However, the administration of mAbs did not interfere with the induction of splenomegaly, the invasion of CD4
+, CD8
+, B220
+, or Mac-1
+ cells around bile ducts, nor the production of AMA. Liver-infiltrating CD4
+ T cells obtained from these treated mice did not alter the expression of T helper (Th)1 and Th2 cytokine mRNA.
Conclusion: The results suggest that treatment with antibodies against these adhesion molecules could inhibit the infiltration of lymphocytes without affecting the Th1/Th2 balance. The blockade of VLA-4-mediated cell infiltration into the liver in this model may have a possible novel therapeutic role of VLA-4 mAbs.
The aim of this study is to clarify the existence and the form of HCV RNA and HBV DNA genome integration and genetic instability in liver tissue with HBsAg-negative and anti-HCV-positive HCC. We ...investigated 16 Japanese patients with HBsAg-negative and anti-HCV-positive HCC. HBV genome integration into host cell genome by Southern hybridization and PCR was examined. Moreover, we analyzed loss of heterozygosity (LOH) and replication errors (RER) of chromosomes 2p, 3p and 17p using the PCR and an autosequencer to determine the three microsatellite regions D2S123, D3S1067, TP53. Eight (50.0%) of 16 were found to have integrated genome of HBV in tumor tissue (T) by PCR. In even the non-tumor regions (NT), seven patients (43.8%) were found to have HBV genome integration. The coincidence between T and NT was found in 4 (25%). Integration of HBV-X gene in T was revealed in three (18.7%), and HBV-integration was confirmed in all NT. No integration of the X gene alone was found in the liver tissue. Five (37.5%) of eight HBV DNA integrated cases simultaneously had HCV RNA minus strand. Concerning the genetic instability, RER were detected in two of 16 (12.5%). RER at 2p; D2S123 was observed in one of 16 (6.2%) and at 3p; D3S1067 was observed in one (6.2%). LOH at the D2S123 locus was observed in one of 12 tumors with heterozygosity (8.3%). There was no genetic instability (LOH or RER) of TP53 which was p53 locus on 17p in T. There was only one case of eight HBV DNA integrated cases (6.2%) with genetic instability of RER of 3p simultaneously in T. In conclusion, the majority of HBsAg-negative and anti-HCV-positive HCC liver tissue was found to have HCV-RNA and HBV DNA integration, and in some samples, HBV DNA integration and genetic instability were concurrently confirmed. It is speculated that multistep carcinogenesis may have been proposed for HCC oncogenetic progression.
Background and Aims: We have previously reported that cluster of differentiation (CD)4+ T cells induced autoimmune liver diseases in mice with graft‐versus‐host reaction (GVHR) because of major ...histocompatibility complex (MHC) class II disparity. To analyze the progression of the autoimmune‐related mechanism in the liver, concanavalin A (Con A) was injected in mice undergoing GVHR. The aim of this study is to clarify whether Con A deteriorates murine hepatic lesions induced by GVHR, and to elucidate the participation of the cytokines of liver‐infiltrating CD4+ T cells.
Methods: Mice (F1; B6.C‐H‐2bm12× B6) were intravenously injected with B6 T spleen cells. Concanavalin A (15 mg/kg) was administrated 5 days after cell transfer. We examined serum transaminase, antimitochondrial antibodies (AMA), antinuclear antibodies (ANA) and histological changes. Liver‐infiltrating CD4+ T cells were sorted and their cytokine mRNA expression was examined by the use of reverse transcription–polymerase chain reaction (RT‐PCR).
Results: Graft‐versus‐host reaction + Con A mice revealed an elevated serum transaminase, elevated AMA and ANA titers, increased periportal cellular infiltration, piecemeal necrosis and bridging necrosis in the liver. In this group, interferon (IFN)‐γ mRNA expression was more elevated than it was in the GVHR mice. However, there was no difference in the expression of interleukin (IL)‐10 mRNA between the two groups.
Conclusion: The results suggest that Con A deteriorates the GVHR‐induced hepatic lesions, and IFN‐γ and IL‐10 of CD4+ T cells might be implicated in the progression of autoimmune‐related hepatic lesions. This model might offer an aspect for the investigation of progressive mechanisms in T‐cell‐ mediated hepatobiliary injury.
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