Ethanol decreases rat hepatic arylsulfatase A activity levels.

BACKGROUND: Arylsulfatase A (ASA) is an enzyme that catalyzes the degradation of sulfatides, a glycosphingolipid found in many tissues, but predominantly in myelin and kidney. Arylsulfatase A is 1 member of a family of sulfatases that is activated by a required co- or posttranslational modification with the oxidation of cysteine to formylglycine. This conversion requires a novel oxygenase mechanism that can be inhibited by reactive oxygen species. Ethanol is known to cause an increase in reactive oxygen species in the liver. Because of its effect on the levels of hepatic reactive oxygen species, we hypothesized that ethanol would cause a specific decrease of rat hepatic ASA activity levels. METHODS: Male Sprague-Dawley rats received ethanol-containing, Lieber-DeCarli liquid diets for 15 days, and control rats were pair-fed a liquid diet in which dextrose was isocalorically substituted for ethanol. RESULTS: Arylsulfatase A activity levels decreased in livers of animals receiving alcohol compared with control animals. No significant changes in ASA activity levels were observed in the cerebral cortex and kidney. Furthermore, ethanol did not have any significant effect on hexosaminidase activity in any of the tissues examined. CONCLUSION: Ethanol caused a tissue-specific decrease in hepatic ASA activity levels, but not hexosaminidase activity levels.

Tyrosine sulfation of arylsulfatase A and its peptide.

Purified human liver arylsulfatase A (ASA) as well as an ASA peptide (residues 28-39) were sulfated by tyrosyl protein sulfotransferase in vitro. The media, but not the cell lysate, of normal human fibroblasts contained a tyrosine sulfated protein (pI = 4.5-5.5). This protein was not present in either media or cell lysate of human fibroblasts lacking ASA protein. These results suggest that tyrosine sulfation facilitates secretion of ASA and that this may have pathophysiological consequences.

Cognitive traits link to human chromosomal regions.

: Human cognition in normal and disease states is both environmentally and genetically mediated. Except for measures of language-specific abilities, however, few cognitive measures have been associated with specific genes or chromosomal regions. We performed genome-wide linkage analysis of five neuropsychological tests in the Collaborative Study on Genetics of Alcoholism sample. The sample included 1579 individuals (53% female, 76% White Non-Hispanic) in 217 families. There were 390 markers with mean inter-marker distance of 9.6 cM. Performance on the Digit Symbol Substitution Test, a component of the Wechsler Adult Intelligence Scale-R, showed significant linkage to 14q11.2 and suggestive linkage to 14q 24.2. This test of sustained visual attention also involves visual-motor coordination and executive functions. Performance on the WAIS-R Digit Span Test of immediate memory and mental flexibility showed suggestive linkage to 11q 25. Although the validity of these results beyond populations with a susceptibility for alcohol dependence is unclear, these results are among the first linkage results for non-language components of cognition.

Tryptophan hydroxylase polymorphism is associated with age of onset of alcoholism related behaviors.

The purpose of this study was to explore the association of a tryptophan hydroxylase gene polymorphism (TPH1 A218C) with the age of alcoholism onset in a Korean population. The genotype and allele frequencies of TPH1 were investigated in 182 male hospitalized patients who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) criteria for alcohol dependence. Alcoholics with the TPH1 AA or AC genotypes had an earlier age of disease onset (median age of onset, 26.5 years) than those with the CC genotype (median age of onset, 30 years; p=.002). Age of onset has been used in classifying alcoholics. The TPH1 polymorphism may explain, in part, the biological basis for these typologies.

The future of proteomics in the study of alcoholism.

This article represents the proceedings of a workshop at the 2003 annual meeting of the Research Society on Alcoholism in Fort Lauderdale, FL. The workshop organizers/chairpersons were Chinnaswamy Kasinathan and Paul Manowitz. The presentations were (1) Introduction to the field of proteomics, by Kent Vrana; (2) Use of proteomics in the identification of urinary biomarkers for alcohol intake, by Chinnaswamy Kasinathan, Paul Thomas, and Paul Manowitz; (3) Proteomics screening illuminates ethanol-mediated induction of HDL proteins in macaques, by Kent Vrana, Randy Gooch, Travis Worst, Stephen Walker, Aaron Xu, Peter Pierre, Heather Green, and Kathleen Grant; and (4) Proteomics applied to the study of the liver, by Laura Beretta.

Evidence for an N-glycosylation polymorphism of arylsulfatase a predisposing to alcoholism in Koreans.

This study investigated the possible effect of the pseudodeficient N-glycosylation polymorphism of the arylsulfatase A (ASA) gene on alcohol dependence among Koreans. Alcoholic patients (N=123) were more likely than control subjects to be heterozygous or homozygous for the ASA pseudodeficient N-glycosylation site (36% of alcoholics versus 20% of controls; P<0.01). Among these 123 alcoholic patients, 42 alcoholics were heterozygous and two were homozygous for the ASA pseudodeficient N-glycosylation polymorphism. This result provides evidence that the ASA pseudodeficient N-glycosylation site allele increases the risk of alcohol dependence within a Korean population.