Effect of type of alcoholic beverages on carbohydrate-deficient transferrin, sialic acid, and liver enzymes.

BACKGROUND: There are only limited data obtained under well controlled conditions on the effects of moderate drinking on markers of alcohol use disorders. The aim of this study was to investigate the effects of moderate intake of different alcoholic beverages on these markers, including carbohydrate-deficient transferrin (CDT), sialic acid (SA), and the liver enzymes gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase. METHODS: Eleven apparently healthy, nonsmoking middle-aged men were included in a 12-week randomized, diet-controlled crossover trial according to a 4 x 4 Latin-square design. Changes in CDT, SA, gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase were analyzed after 3 weeks of daily intake of four glasses (40 g of alcohol) of red wine, beer, spirits (Dutch gin), or water (control). RESULTS: After 3 weeks' daily consumption of red wine, a significant decrease of serum CDT concentration was observed compared with water consumption. There was no effect of any alcoholic beverage on the other outcome measures. CONCLUSIONS: Daily consumption of 40 g of alcohol from different types of alcoholic beverages with dinner did not affect SA or liver enzymes. Further investigations to explore the mechanisms for the red wine-induced decreases of CDT, including changes in iron metabolism, are clearly needed.

The role of biomarkers in alcoholism medication trials.

BACKGROUND: Increasingly, biomarkers are being incorporated into the research design of clinical trials on medications to reduce drinking in alcoholics. To date, however, there has been little analysis of the unique roles that biomarkers can play in such investigations or of the practical and conceptual considerations that surround their best use in this context. METHODS: Clinical trials of alcoholism medications published between 1985 and the present were abstracted to determine how biomarkers were used and how changes in them related to self-report measures of drinking. RESULTS: Six uses of biomarkers were identified: determination of subjects to be included or excluded in the trial; description of baseline sample characteristics; primary and secondary outcome assessment; corroboration of self-reports of drinking status; specification of patients likely to respond to the medication; and evaluation of drug safety. CONCLUSION: Use of biomarkers in such studies appears warranted, particularly as an objective source of information on treatment efficacy that can be considered with patient self-report measures of drinking status. Biomarkers related to liver functioning also can assist in determination of drug safety for medications metabolized by the liver.

Association of self-reported diseases and health care use with commonly used laboratory markers for alcohol consumption.

The relationships of carbohydrate-deficient transferrin (CDT), gamma-glutamyltransferase (GGT) and their mathematical combination (gamma-CDT) with self-reported diseases were evaluated in a large cross-sectional risk factor survey. Significant gender effects were observed in associations of the markers with several medical conditions as well as with general health care utilization. In men, CDT was associated with rheumatoid arthritis. In both genders, GGT was positively associated with hypertension and diabetes. gamma-CDT was positively associated with hypertension in males and with asthma in females. This general population study demonstrates that these markers, although most commonly used to assess alcohol misuse, might also serve as health risk indicators.

Possible reasons why heavy drinking increases carbohydrate-deficient transferrin.

BACKGROUND: Transferrin is a globular protein synthesized in the liver that is responsible for iron transport in plasma. The structure of the molecule consists of two carbohydrate residues to which six sialic acid moieties can be attached. After periods of chronic, heavy alcohol consumption, carbohydrate-deficient transferrin (CDT) isoforms often increase, which makes CDT a useful marker in screening for alcohol abuse and monitoring progress of alcoholics in treatment. However, the precise mechanism behind CDT increase remains unknown. METHODS: A review of the most relevant literature on CDT was conducted with a computer-assisted literature search. RESULTS: During the past several years, a number of studies have explored possible mechanisms that may account for the alcohol-induced increase of CDT. An inhibition of protein synthesis and a general effect of alcohol on protein glycosylation have been reported. Although the exact mechanisms that underlie production of CDT are not yet fully understood, possible bases for the phenomenon are presented in this article. CONCLUSIONS: Experimental findings indicate that the ethanol-induced effect on glycoprotein metabolism is a multistep process in which protein transport and changes of enzyme activity may play an important role.

Association of carbohydrate-deficient transferrin (CDT) and gamma-glutamyl-transferase (GGT) with serum lipid profile in the Finnish population.

BACKGROUND: Moderate consumption of alcohol may reduce mortality from vascular diseases. The beneficial effects of alcohol may partly be mediated by its effects on lipoprotein metabolism. We studied the connection between alcohol consumption and the serum lipid profile from a well-documented national health program study. METHODS AND RESULTS: Carbohydrate-deficient transferrin (CDT) and gamma-glutamyl-transferase (GGT) were used as biochemical markers for alcohol consumption. The laboratory analyses were carried out on 5675 subjects (3097 males and 2578 females). The subjects were divided into quartiles on the basis of CDT or GGT value. The highest CDT quartile and the lowest GGT quartile seemed to be associated with a favorable lipid profile and the lowest CDT quartile and the highest GGT quartile were associated with an unfavorable lipid profile. Serum high density lipoprotein (HDL) cholesterol values were significantly higher and triglycerides lower with increasing serum CDT concentrations for both men and women. Increasing serum GGT was associated with higher serum total cholesterol and higher triglycerides in both men and women and lower HDL cholesterol in men. CONCLUSIONS: CDT and GGT seem to detect different populations of subjects in regard to lipid metabolism. These observations may lead to a better understanding of the effects of alcohol consumption on lipids as well as mechanisms behind favorable and detrimental effects of alcohol on vascular diseases. CONDENSED ABSTRACT: Carbohydrate-deficient transferrin (CDT) and gamma-glutamyl-transferase (GGT) were used as biochemical markers for alcohol consumption. A total of 3097 males and 2578 females were divided into quartiles on the basis of their CDT or GGT values. The highest CDT quartiles had higher HDL and lower triglycerides, whereas the highest GGT quartiles appeared to be associated with higher total cholesterol and triglycerides in both genders and lower HDL in men. CDT and GGT seem to detect different populations of subjects in regard to lipid metabolism. These observations may have important clinical and public health implications.