DNA methylation patterns in alcoholics and family controls

AIM: To assess whether DNA methylation patterns in chronic alcoholics are different from non-alcoholic sibling controls. METHODS: We examined the methylation patterns in DNA samples from 25 chronic alcoholics and 22 matched siblings as controls (one per family). DNA was extracted from peripheral blood and analyzed for differences in the methylation patterns after bisulfite-conversion. We used the Illumina GoldenGate Methylation Cancer Panel I (Illumina, San Diego, CA), which probes the methylation profile at 1505 CpG sites from 807 cancer related genes. We excluded the 84 X-chro- mosome CpG sites and 134 autosomal CpG sites that failed to show a within sample reliability score of at least 95% for all samples, leaving 1287 autosomal CpG sites (associated with 743 autosomal genes) with reliable signals for all samples. A methylation score was calculated as the average methylation for the 1287 CpG sites examined. Differences were assessed by a two-sample t-test. We also examined the average sib pair differences in methylation scores at each of the 1287 sites. All analyses were performed using SPSS, version 9.0, P < 0.05 was considered significant. RESULTS: Methylation levels at the 1287 CpG sites averaged 28.2% for both alcoholics and controls. The mean difference in methylation scores between alcoholic and non-alcoholic sibs by CpG site was < 1% with small inter-individual variances; and only 5 CpG sites had an average sib difference > 5%. Subgroup analysis showed that methylation scores were significantly lower for the alcoholic-dependent subjects who smoked compared to their non-smoking unaffected siblings. Specifically, among smokers who are alcoholic, global methylation indices were significantly lower than in nonalcoholic sib controls, whereas among non-smoking alcoholics, the global indices were significantly higher (P = 0.008). CONCLUSION: Although we observed no effect of alcoholism alone on DNA methylation, there is a decrease in alcoholics who smoke, suggesting a mechanism for alcohol-tobacco synergy for carcinogenesis.     

Hepatotoxicity due to troglitazone: report of two cases and review of adverse events reported to the United States Food and Drug Administration

Two patients (a 48-year-old woman and a 62-year-old man) developed clinical and laboratory signs of hepatotoxicity due to troglitazone (Rezulin), a thiazolidinedione used in treatment of diabetes mellitus. There was no clear clinical evidence of drug allergy, although the woman experienced colitis before the onset of recognized hepatotoxicity. Liver biopsies showed bridging necrosis and fibrosis in the woman and hepatitis with granuloma formation in the man. The abnormalities in liver chemistries resolved promptly upon cessation of the drug. Cases involving 46 patients reported to the United States Food and Drug Administration are also reviewed. Troglitazone is a useful new oral antihyperglycemic agent, but in about 1.9% of patients hepatotoxicity has occurred, which may be severe and even fatal. Frequent monitoring of serum liver chemistries in patients taking the drug is essential.     

Osteocalcin and bone alkaline phosphatase in the serum of women with liver disease

To identify the types of liver disease in which osteopenia is a prominent feature and to understand the mechanisms of bone loss, bone mineral density was measured in the lumbar spine and hip, bone alkaline phosphatase, osteocalcin, and biochemical markers of calcium homeostasis were measured in 42 women, aged 33 to 52, with chronic liver disease and in 299 healthy women of similar age. In control women, bone alkaline phosphatase and osteocalcin correlated negatively with bone density at all sites (p less than 0.05). In women with liver disease, osteocalcin correlated negatively with bone density in the lumbar spine (p less than 0.007), whereas bone alkaline phosphatase did not correlate with bone density at any site. Bone alkaline phosphatase correlated positively with osteocalcin in control women (p = 0.001) and negatively with osteocalcin in women with liver disease (p = 0.03). Serum bone alkaline phosphatase in women with liver disease was increased significantly over serum bone alkaline phosphatase of control women, probably because of decreased clearance owing to defective function or decreased numbers of hepatic asialoglycoprotein receptors. Bone density was lower in the lumbar spines and hips of women with primary sclerosing cholangitis, primary biliary cirrhosis, and chronic active hepatitis or fibrosis without cirrhosis than in the lumbar spine and hips of control women. However, the differences were not significant, possibly because of the small sample size. It is concluded that, in liver disease, osteocalcin is a more reliable marker of osteoblastic function than bone alkaline phosphatase. Although our results show that bone density may decrease in women with cholestatic liver disease, larger studies are needed to determine the degree of osteopenia.     

Effects of antidepressants and benzodiazepine-type anxiolytic agents on hepatic porphyrin accumulation in primary cultures of chick embryo liver cells

Patients with any of the acute porphyrias may suffer from acute attacks. If these patients are treated with certain drugs, such as barbiturates, the likelihood of developing an attack is increased. Patients treated with antidepressants or benzodiazepine-type anxiolytics also could be placed at increased risk of developing porphyric attacks because little is known about the potential for some of these drugs to induce attacks. Primary cultures of chick embryo liver cells were used to study the effects of selected antidepressants and anxiolytics on porphyrin accumulation. Cells were treated with desferrioxamine (to partially block heme synthesis, simulating conditions encountered in porphyric patients) and increasing concentrations (3.16-1000 microM) of the evaluated drugs. Twenty hours later, porphyrin accumulation was measured. The drugs included four antidepressants and five benzodiazepine-type anxiolytics. The antidepressants bupropion and nefazodone significantly increased porphyrin accumulation when given with desferrioxamine, whereas neither fluoxetine nor paroxetine increased porphyrin accumulation. The benzodiazepine-type anxiolytic agents oxazepam, lorazepam, diazepam, triazolam, and midazolam all significantly increased porphyrin accumulation when given with desferrioxamine. Dose-response studies showed that diazepam, midazolam, and triazolam produced significant increases even at the lowest concentration tested (3.16 microM), whereas lorazepam and oxazepam required higher concentrations (>/=10 microM). These studies suggest that patients with acute porphyrias may be at greater risk for developing porphyric attacks when treated with bupropion or nefazodone compared with fluoxetine or paroxetine, and that the evaluated benzodiazepine derivatives should be administered with caution. Among the latter, low doses of lorazepam and oxazepam may be safer than those of diazepam, midazolam, and triazolam.     

Inflammatory markers in chronic hepatitis C

 To test the hypothesis that inflammation in hepatitis C follows mechanisms common to immune-activated pathways, the distributions of T and B cells, adhesion molecules and transforming growth factor-β (TGF-β) were assessed in liver biopsies with chronic inflammation due to hepatitis C (HCV, n=8) and other causes (non-HCV, n=10). Frozen sections were immunostained using primary antibodies to CD2, CD20, CD4, CD8, intercellular adhesion molecule (ICAM-1), vascular cell adhesion molecule (VCAM)-1, HLA-DR, lymphocyte function-associated antigen (LFA)-1, and TGF-β. Inflammatory cells positive for each immunophenotypic marker were counted, and positive staining for adhesion molecules, HLA-DR and TGF β was graded in triads and lobules and compared in HCV and non-HCV biopsies. In all biopsies, T cells were more frequent than B cells, both in triads and lobules. CD20+, CD4+, CD8+ and LFA-1+ cells were increased in HCV compared to non-HCV biopsies. Portal lymphoid aggregates were present in 6 of 8 HCV biopsies and 3 of 10 non-HCV biopsies. Aggregates consisted of CD20+, CD4+, CD8+ and LFA-1+ cells, and ICAM-1 and VCAM-1 were increased. Sinusoidal lining cells in HCV biopsies and non-HCV biopsies with inflammation expressed HLA-DR, ICAM-1, and CD4. TGF-β was increased in foci of necrosis. Inflammation in chronic HCV involves common immune-mediated cellular effector pathways and the inflammation in the portal triads represents aggregation of both T and B cells, mediated in part by upregulation of adhesion molecules on portal stromal cells; this is possibly in response to antigens draining from necroinflammatory foci in the lobules. TGF-β is increased in active necroinflammatory foci, but not in portal lymphoid aggregates. Received: 5 November 1996 / Accepted: 18 February 1997     

Effects of selected antihypertensives and analgesics on hepatic porphyrin accumulation: implications for clinical porphyria.

When patients with acute porphyrias are treated with antihypertensives and analgesics, they could be placed at increased risk of developing porphyric attacks, since little is known about the potential for many of these drugs to induce these attacks. We used primary chick embryo liver cells, which maintain intact heme synthesis and regulation, to study the effects of antihypertensives and analgesics on porphyrin accumulation. Cells were treated with desferrioxamine to block heme synthesis partially, simulating conditions encountered in porphyric patients. Typically, cells were treated for 20 hr with the test drugs (3.16 to 1000 microM), along with desferrioxamine. Porphyrins were measured spectrofluorometrically, as uro-, copro,- and protoporphyrin. The evaluated drugs included six antihypertensives (two calcium channel blockers, an angiotensin receptor antagonist, and three inhibitors of angiotensin converting enzyme) and eight analgesics. Of the calcium channel blockers tested, nifedipine greatly increased porphyrin accumulation, whereas diltiazem caused only a slight increase. Losartan (an angiotensin receptor antagonist), captopril, or lisinopril (two angiotensin converting enzyme inhibitors) produced only small increases in porphyrin accumulation. In contrast, enalapril (another angiotensin converting enzyme inhibitor) substantially increased porphyrin accumulation when given in high concentrations. Among the analgesics tested, fentanyl and tramadol produced the highest porphyrin accumulations. Nalbuphine, hydrocodone, oxycodone, and dezocine were moderately or weakly porphyrogenic, whereas buprenorphine and morphine did not increase porphyrin accumulation. These studies suggest that patients with acute porphyrias may be at greater risk for developing porphyric attacks when treated with nifedipine (compared with diltiazem), enalapril (compared with captopril or lisinopril), and tramadol (compared with the other analgesics).     

Marked hyperbilirubinemia associated with the heme oxygenase-1 gene promoter microsatellite polymorphism in a boy with autoimmune hemolytic anemia

Mild hyperbilirubinemia is a clinical feature of hemolysis. Here we describe a boy with marked elevation of serum bilirubin values (maximum: 70 mg/dL) during an acute episode of autoimmune hemolytic anemia, which returned to within the reference range after clinical improvement. The boy was a homozygous carrier of short alleles of the heme oxygenase-1 (HO-1) gene GT dinucleotide-repeat promoter polymorphism, which is associated with increased activity and inducibility of the heme-degrading enzyme HO-1, which catalyzes the production of bilirubin. In addition, heterozygosity of the uridine 5'-diphosphate-glucuronosyl-transferase 1A1 promoter polymorphism that is linked with Gilbert syndrome was found in this patient. Because bilirubin production plays a critical role during the neonatal period, the HO-1 promoter polymorphism may be an important genetic factor for the clinical outcome of neonatal hyperbilirubinemia.