Novel serum biomarkers for detection of excessive alcohol use.

BACKGROUND: Construct interview that correctly identifies those with alcohol use disorder have limitation, especially when the subjects are motivated to minimize the magnitude of drinking behavior. Current laboratory tests to detect excessive alcohol consumption are limited by marginal sensitivity/specificity. Excessive drinking has been shown to affect several organ systems, which may be reflected in changes in quantity of plasma proteins. Our aim was to employ novel proteomic analyses to identify potential markers for excessive alcohol use. METHODS: A prospective case-control study included 49 controls and 54 excessive drinkers (discovery cohort). The serum proteomic analyses in these subjects were performed, and the results were tested in the verification cohort (40 controls and 40 excessive drinkers). RESULTS: Using the appropriate cutoff and confirmation with ELISA, we identified 4 proteins which were significantly elevated in the serum of excessive drinkers: AT-rich interactive domain-containing protein 4B (ARID4B), phosphatidylcholine-sterol acyltransferase (LCAT), hepatocyte growth factor-like protein (MST1), and ADP-ribosylation factor 6 (ARL6). The performance of the conventional markers (aspartate aminotransferase [AST], alanine aminotransferase [ALT], gamma-glutamyl transpeptidase [GGT], percentage of carbohydrate-deficient transferrin [%CDT], and mean corpuscular volume [MCV]) discriminating between excessive alcohol use and controls had an area under the curve (AUC) ranging from 0.21 (ALT) to 0.67 (MCV). The AUC of these novel proteins showed the improvement in the detection of excessive drinkers compared to conventional laboratory tests, ranging from 0.73 (for ARID4B) to 0.86 (for ARL6). CONCLUSIONS: We have identified 4 novel proteins that can discern subjects with excessive alcohol use. Further studies are needed to determine the clinical implications of these markers to detect excessive alcohol use and confirm abstinence.

Quantity of alcohol drinking positively correlates with serum levels of endotoxin and markers of monocyte activation.

It is unknown if LPS (lipopolysaccharides) and markers of immune activation, soluble CD14 (sCD14) and CD163 (sCD163) are associated with the quantity of alcohol consumption. 148 subjects were enrolled (97 excessive drinkers (ED) and 51 controls). Time Line Follow-Back questionnaire was used to quantify the amount of alcohol consumed. Serum LPS, sCD14, and sCD163 were measured. Peripheral blood mononuclear cells (PBMCs) were also isolated. Compared to controls, ED had higher total drinks in the past 30 days, higher levels of LPS, sCD14 and sCD163. The levels of serum LPS, sCD14, and sCD163 were higher among ED with recent alcohol consumption (last drink <10 days before enrollment) compared to those without recent drinking. Similar bacterial genome copy numbers were detected in control and ED groups. We found that ethanol primed PBMCs for LPS-induced inflammatory responses. A positive correlation between serum LPS, sCD14, sCD163 and the quantity of alcohol drinking was observed after adjusting for covariates and that abstinence was associated with decline in the levels of LPS, sCD14 and sCd163. We found an increase in the levels of LPS and markers of monocyte activations in ED. Further studies are needed to determine whether these can be used as the biomarkers for excessive alcohol use.