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.

Dose response of laboratory markers to alcohol consumption in a general population.

The dose response to alcohol use of carbohydrate-deficient transferrin (CDT), gamma-glutamyltransferase (GGT), and their combination (gamma-CDT) was studied in an age- and gender-stratified, random sample from Finland in 1997. A linear association with a threshold between alcohol consumption and the three markers was observed. Body mass index was negatively associated with CDT and positively with GGT Age was positively associated with GGT and gamma-CDT In conclusion, CDT appears to be an early phase marker of alcohol consumption. The combined marker, gamma-CDT, was less associated with factors such as body mass index but more strongly correlated with alcohol consumption than were the two markers separately.

Association of serum sialic acid and MMP-9 with lipids and inflammatory markers.

BACKGROUND: Inflammation of the arterial wall has emerged to be an important contributor to the process of atherosclerosis, the major cause of coronary heart disease. Several factors are currently under investigation as inflammatory markers of atherosclerosis. Serum sialic acid and matrix metalloproteinase-9 may provide such markers. We studied their association with the lipid profile and with the inflammatory markers C-reactive protein and leukocyte count in a clinically healthy population of men. MATERIALS AND METHODS: Cardiovascular risk-related laboratory tests were carried out in 65 consecutive male employees in connection with an occupational health survey in 1996. The subjects were divided into tertiles on the basis of serum sialic acid or matrix metalloproteinase-9 concentration. RESULTS: In a stepwise polychotomous logistic regression model adjusting for coronary heart disease risk factors, serum sialic acid concentration was not associated with markers of inflammation but rather with the lipid risk factors of atherosclerosis: inversely with HDL cholesterol (OR = 0.081, 95% CI 0.0068-0.97) and positively with total cholesterol (OR = 2.4, 95% CI 1-5.6). Matrix metalloproteinase-9 levels had a significant positive correlation with the leukocyte count (OR = 2.3, 95% CI 1.4-4). CONCLUSIONS: Serum sialic acid does not appear to be an indicator of inflammation but is somehow connected with the level of total and HDL cholesterol. Serum matrix metalloproteinase-9 may provide a useful marker of inflammation because it correlates with the leukocyte count and is not associated with the lipid profile.

Serum sialic acid in a random sample of the general population.

BACKGROUND: The serum sialic acid (SA) concentration has been reported to be a potentially useful but nonspecific disease marker. We wanted to study which factors influence SA concentration in a well-characterized healthy population. METHODS: SA was determined in 97 women and 96 men with a colorimetric Warren method. RESULTS: The mean +/- SD concentrations of SA were 634 +/- 109 (95% confidence interval, 612-656) and 630 +/- 106 (95% confidence interval, 608-651) mg/L for women and men, respectively. The serum SA showed a significant positive association with body mass index and with systolic and diastolic blood pressure among both women and men. SA also correlated significantly with the use of contraceptive pills and age among women and with smoking among men. CONCLUSIONS: Our study suggests that SA does not increase with age in men but appears to increase with female menopause. The strong positive association with blood pressure may explain why SA predicts cardiovascular mortality.

Sialic acid: new potential marker of alcohol abuse.

BACKGROUND: A number of laboratory markers are suggested for the detection and monitoring of alcohol abuse. However, there is still a need to find better indicators of alcohol abuse. Sialic acid (SA) is the name for a series of acyl-derivatives of neuraminic acids that occur as nonreducing terminal residues of glycoproteins or glycolipids in biological fluids and cell membranes. In this study, we investigated the diagnostic value of SA as a marker of alcohol abuse. METHODS: Sera from social drinkers (n = 38) and alcoholics (n = 77) were analyzed for sialic acid by a colorimetric assay and for carbohydrate-deficient transferrin (CDT) by a radioimmunoassay method. Mean corpuscular volume (MCV), gamma-glutamyltransferase (GGT), aspartate aminotransferase (ASAT), and alanine aminotransferase (ALAT) were determined by using routine methods. RESULTS: The sialic acid levels of both female and male subjects were significantly (p < 0.001) increased among alcoholic subjects when compared with social drinkers. SA levels were decreased after 3 weeks of treatment. The sensitivity and specificity for SA, respectively, were 57.7 and 95.5 for women and 47.8 and 81.3 for men. The respective values for CDT were 57.7 and 95.5 for women and 78.3 and 100.0 for men; for GGT, 60.0 and 95.5 for women and 60.9 and 87.5 for men; for MCV, 52.4 and 95.5 for women and 47.8 and 100.0 for men; for ASAT, 53.8 and 95.5 for women and 43.5 and 100.0 for men; and for ALAT, 38.5 and 90.9 for women and 39.1 and 87.5 for men. Among women, SA and GGT, and among men CDT, showed the largest area under receiver operation curve. CONCLUSION: This study indicated that sialic acid levels were elevated by high alcohol consumption and reduced during abstinence, especially among women. Thus, sialic acid seems to be an interesting marker that needs further evaluation as a diagnostic tool for alcohol abuse.

Serum and saliva levels of sialic acid are elevated in alcoholics.

BACKGROUND AND METHODS: Recently, sialic acid has been suggested as a potential marker for alcohol abuse. In this study, social drinkers and alcoholics were analyzed with a modified version of Warren's method for sialic acid and traditional markers of alcohol abuse in serum (n = 38; n = 87), saliva (n = 36; n = 29), and urine (n = 37; n = 83), respectively. The alcoholics were participating in an alcohol dependency treatment program and were followed in this study for 5 weeks. RESULTS: The sialic acid concentrations in female and male alcoholics were significantly higher in serum (p < 0.001;p < 0.001 respectively) and saliva (p < 0.05; p < 0.05) but not in urine, compared with social drinkers. The diagnostic efficiency of serum sialic acid was higher than that for traditional markers: 77% for female subjects and 64% for male subjects. The corresponding results for saliva were 72% and 53%. The sialic acid concentrations were significantly decreased during the alcohol dependency treatment program (after 5 weeks of treatment) in both females and males. CONCLUSIONS: This study confirms that serum sialic acid is a valuable marker for detecting and monitoring alcohol abuse. This work also indicates that sialic acid in saliva could be used possibly as a noninvasive marker for alcohol abuse.

Occurrence of sialic acids in healthy humans and different disorders.

Sialic acid (SA), N-acetylated derivatives of neuraminic acid, play a central role in the biomedical functioning of humans. The normal range of total sialic acid (TSA) level in serum/plasma is 1.58-2.22 mmol L-1, the free form of SA only constituting 0.5-3 mumol L-1 and the lipid-associated (LSA) forms 10-50 mumol L-1. Notably, considerably higher amounts of free SA are found in urine than in serum/plasma (approximately 50% of the total SA). In inherited SA storage diseases such as Salla's disease, SA levels are elevated many times over, and their determination during clinical investigation is well established. Furthermore, a number of reports describe elevated SA levels in various other diseases, tentatively suggesting broader clinical utility for SA markers. Increased SA concentrations have been reported during inflammatory processes, probably resulting from increased levels of richly sialylated acute-phase glycoproteins. A connection between increased SA levels and elevated stroke and cardiovascular mortality risk has also been reported. In addition, SA levels are slightly increased in cancer, positively correlating with the degree of metastasis, as well as in alcohol abuse, diabetes, chronic renal failure and chronic glomerulonephritis. Several different mechanisms are assumed to underlie the elevated SA concentrations in these disorders. The apparent non-specificity of SA to a given disease limits the potential clinical usefulness of SA determination. In addition, some non-pathological factors, such as aging, pregnancy and smoking, may cause changes in SA concentrations. The absolute increases in SA levels are also rather small (save those in inherited SA storage disorders); this further limits the clinical potential of SA as a marker. Tentatively, SA markers might serve as adjuncts, when combined with other markers, in disease screening, disease progression follow-up, and in the monitoring of treatment response. To become clinically useful, however, the existing SA determination assays need to be considerably refined to reduce interferences, to be specific for certain SA forms, and to be more easy to use.