Sławomir Dariusz Szajda

Alcohol abuse and glycoconjugate metabolism

The relationship between alcohol consumption and glycoconjugate metabolism is complex and multidimensional. This review summarizes the advances in basic and clinical research on the molecular and cellular events involved in the metabolic effects of alcohol on glycoconjugates (glycoproteins, glycolipids, and proteoglycans). We summarize the action of ethanol, acetaldehyde, reactive oxygen species (ROS), nonoxidative metabolite of alcohol — fatty acid ethyl esters (FAEEs), and the ethanol-water competition mechanism, on glycoconjugate biosynthesis, modification, transport and secretion, as well as on elimination and catabolism processes. As the majority of changes in the cellular metabolism of glycoconjugates are generally ascribed to alterations in synthesis, transport, glycosylation and secretion, the degradation and elimination processes, of which the former occurs also in extracellular matrix, seem to be underappreciated. The pathomechanisms are additionally complicated by the fact that the effect of alcohol intoxication on the glycoconjugate metabolism depends not only on the duration of ethanol exposure, but also demonstrates dose- and regional-sensitivity. Further research is needed to bridge the gap in transdisciplinary research and enhance our understanding of alcohol- and glycoconjugate-related diseases.

The Effect of the Binge Drinking Session on the Activity of Salivary, Serum and Urinary β-Hexosaminidase: Preliminary Data

Our report is the first to show that an acute ingestion (6 h) of a relatively large, yet tolerable dose of alcohol (120-160 g), significantly increases activity of total serum beta-hexosaminidase (total beta-HEX), beta-HEX A and beta-HEX B isoenzymes, as well as salivary total beta-HEX and urinary beta-HEX A, in eight infrequent binge drinkers. An increase in the activity of serum and urinary total HEX is mainly due to its secretory isoenzyme beta-HEX A.

Glycoconjugates in the detection of alcohol abuse

Up to 30% of all hospital admissions and health-care costs may be attributable to alcohol abuse. Ethanol, its oxidative metabolites, acetaldehyde and ROS (reactive oxygen species), non-oxidative metabolites of alcohol [e.g. FAEEs (fatty acid ethyl esters)] and the ethanol-water competition mechanism are all involved in the deregulation of glycoconjugate (glycoprotein, glycolipid and proteoglycan) metabolic processes including biosynthesis, modification, transport, secretion, elimination and catabolism. An increasing number of new alcohol biomarkers that are the result of alcohol-induced glycoconjugate metabolic errors have appeared in the literature. Glycoconjugate-related alcohol markers are involved in, or are a product of, altered glycoconjugate metabolism, e.g. CDT (carbohydrate-deficient transferrin), SA (sialic acid), plasma SIJ (SA index of apolipoprotein J), CETP (cholesteryl ester transfer protein), β-HEX (β-hexosaminidase), dolichol, EtG (ethyl glucuronide) etc. Laboratory tests based on changes in glycoconjugate metabolism are useful in settings where the co-operativeness of the patient is impaired (e.g. driving while intoxicated) or when a history of alcohol use is not available (e.g. after trauma). In clinical practice, glycoconjugate markers of alcohol use/abuse let us distinguish alcoholic from non-alcoholic tissue damage, having important implications for the treatment and management of diseases.

The Effect of Acute Ethanol Intoxication on Salivary Proteins of Innate and Adaptive Immunity

BACKGROUND Human salivary proteins: peroxidase, lysozyme, lactoferrin, and IgA, participate in the protection of oral tissues, as well as upper digestive and respiratory tracts, against a number of microbial pathogens. In the current study, we investigated the effect of acute consumption of a large dose of ethanol on representative human salivary proteins of the innate and adaptive immune systems. METHODS Eight healthy male volunteers drank an average of 2.0 g (1.4 to 2.5 g/kg) body weight of ethanol, in the form of vodka, in the 6-hour period. Samples of resting whole saliva were collected 12 hours before, then 36 and 108 hours after, the alcohol consumption. The levels of total protein, immunoglobulin A, lysozyme and lactoferrin as well as peroxidase activity were determined in saliva. RESULTS At 36 hours after alcohol consumption, salivary protein and lysozyme concentrations as well as peroxidase activity were significantly decreased (p = 0.002, p = 0.043, and p = 0.003, respectively), in comparison to the values obtained at 12 hours before drinking. Between 36 and 108 hours after alcohol consumption, the salivary protein and lysozyme concentrations, as well as peroxidase activity showed a tendency to increase, although at 108 hours after the drinking session, the concentration of protein and peroxidase activity were still significantly lower than before drinking. There was no significant change in the level of lactoferrin, after the drinking session. The salivary concentration of IgA tended to increase at 36 hours after alcohol consumption, and at 108 hours it was significantly higher (p = 0.028), when compared to IgA concentration in the saliva collected before drinking (from 8% to 26% and 32% of total protein content, respectively). CONCLUSION Our report is the first to show that acute ingestion of relatively large, yet tolerable dose of alcohol, significantly disturbs salivary antimicrobial defense system. Reduced lysozyme level and decreased peroxidase activity may contribute to increased susceptibility to infections, when acute alcohol intake coincides with exposure to pathogens.

Exoglycosidase markers of diseases.

Exoglycosidases are hydrolases involved in lysosomal degradation of oligosaccharide chains of glycoconjugates (glycoproteins, glycolipids and proteoglycans). In tissues and body fluids, a higher exoglycosidase specific activity is found in N-acetyl-β-hexosaminidase, than β-glucuronidase, α-L-fucosidase, β-galactosidase, α-mannosidase and α-glucosidase. Determination of exoglycosidases (especially N-acetyl-β-hexosaminidase and β-glucuronidase) in body fluids could be an inexpensive, easy to perform and sensitive test for pathological evaluation, as well as in screening and monitoring many diseases, including alcohol abuse, risk of arteriosclerosis, bacterial infections (e.g. Lyme borreliosis), chronic inflammatory processes, such as rheumatoid arthritis and juvenile idiopathic arthritis, asthma, autoimmune hepatitis and primary biliary cirrhosis, as well as cancers.

The activity of selected glycosidases in salivary gland tumors.

The monitoring of the patients after salivary gland tumors surgery is an important clinical issue. Still imperfect diagnostic procedures also remain a challenge for searching new sensitive and specific biomarkers of neoplastic processes in salivary glands. The aim of the presented study was an the assessment of the activity of HEX, with its isoforms HEX-A and HEX-B, GLU, GAL, MAN and FUC in salivary gland tumor tissues in comparison to a healthy salivary gland tissues taken during autopsy. A group of 42 patients with benign and malignant salivary gland tumors, aged 25-65 were examined. Fragments of salivary gland tumor tissue, fragments of healthy tissue removed during autopsy, blood serum and saliva were collected from patients with salivary gland tumors and healthy volunteers. In salivary gland tumor tissue the activity of HEX, HEX-A, HEX-B, GAL, FUC was considerably higher than in comparison to healthy salivary gland tissue and ascending trend of activity of GLU, MAN was also noticed. The activity of all lysosomal exoglycosidases in blood serum in patients with salivary gland tumors was considerably higher in comparison to healthy volunteers blood serum. The considerably higher activity of HEX, HEX-A, GLU, GAL, MAN, FUC and descending trend of activity of HEX-B were noticed in saliva of patients with salivary gland tumors in comparison to healthy volunteers. The assessment of HEX in blood serum and saliva of patients with salivary gland tumor can be possibly used in diagnostics and monitoring of salivary glands tumors.

Activity of lysosomal exoglycosidases in serum and synovial fluid in patients with chronic Lyme and rheumatoid arthritis

Lysosomal exoglycosidases participate in the destruction of the articular cartilage by cleaving glycoside bonds in glycoproteins and proteoglycans. The aim of the study was to determine the activity of exoglycosidases: hexosaminidase, β-glucuronidase, β-galactosidase, α-mannosidase and α-fucosidase in serum and synovial fluid of patients with Lyme and rheumatoid arthritis. The study group consisted of 10 patients with chronic Lyme arthritis (age 18 – 74 y), 13 with rheumatoid arthritis (age 32 – 70 y) and 10 with juvenile idiopathic arthritis (age 8 – 17 y). The control group consisted of 9 healthy volunteers (age 24 – 62 y). The activity of the exoglycosidases was determined with the p-nitrophenyl derivatives of sugars as substrates. A significant increase of the activity of all the exoglycosidases in serum and in synovial fluid of the patients with different forms of arthritis was found. The ratio of synovial fluid/serum activity of exoglycosidases was above 2.0 in LA but not in JIA and RA patients. As the main source of exoglycosidases in the joint is the synovial membrane, this result supports the appropriateness of therapeutic synovectomy in chronic Lyme arthritis with knee effusion. The serum activity of hexosaminidase may be used in monitoring the course of Lyme arthritis and the efficiency of treatment.

Salivary hexosaminidase in smoking alcoholics with bad periodontal and dental states

BACKGROUND A sensitive alcohol marker, β-hexosaminidase (HEX), in the saliva of alcoholics, is investigated for the first time. METHODS The activity, specific-activity and output of total HEX and its isoenzymes HEX A and HEX B were measured in the saliva of healthy controls (C), alcohol-dependent non-smokers (ANS), and alcohol-dependent smokers (AS). RESULTS We observed a significantly increased activity/specific-activity and output of HEX A in the ANS and AS groups, due to the inflammatory state of the oral-cavity/salivary-glands. Significantly increased activity of HEX A contributed to an increase in the salivary activity of the total HEX in the ANS group. A significant decrease in the activity/specific-activity of HEX B in AS seemed to be due to HEX B inactivation by cigarette smoke. We noticed a tendency for deteriorated dental state (lower decayed-missing-filled-teeth index - DMFT), worse periodontal state (higher gingival index - GI and papilla-bleeding index - PBI) in AS, and worse periodontal state (higher GI) in ANS, as compared to the controls. We found no differences in the salivary protein concentrations between all groups and decreased salivary flow in both alcoholic groups as compared to the controls. In alcoholics, the area under the curve (AUC) for HEX A activity/specific-activity was significantly greater than for HEX and HEX B. The salivary HEX A activity/specific-activity had good/excellent sensitivity and specificity in smoking and non-smoking alcoholics, whereas salivary HEX and HEX B had poor/fair sensitivity and specificity. CONCLUSIONS Salivary HEX A may be helpful in the diagnosis of chronic alcohol intoxication, even in smokers.

Decrease in salivary lactoferrin output in chronically intoxicated alcohol-dependent patients

Salivary lactoferrin is a glycoprotein involved in the elimination of pathogens and the prevention of massive overgrowth of microorganisms that affect oral and general health. A high concentration of lactoferrin in saliva is often considered to be a marker of damage to the salivary glands, gingivitis, or leakage through inflamed or damaged oral mucosa, infiltrated particularly by neutrophils. We conducted a study to determine the effect of chronic alcohol intoxication on salivary lactoferrin concentration and output. The study included 30 volunteers consisting of ten non-smoking male patients after chronic alcohol intoxication (group A), and 20 control nonsmoking male social drinkers (group C) with no history of alcohol abuse. Resting whole saliva was collected 24 to 48 hours after a chronic alcohol intoxication period. Lactoferrin was assessed by enzyme-linked immunosorbent assay. For all participants, the DMFT index (decayed, missing, or filled teeth), gingival index (GI) and papilla bleeding index (PBI) were assessed. The differences between groups were evaluated using the Mann-Whitney U test. We noticed significantly decreased salivary flow (SF) in alcohol dependent patients after chronic alcohol intoxication (A), compared to the control group (C). Although there was no significant difference in salivary lactoferrin concentration between the alcohol dependent group A and the control group C, we found significantly decreased lactoferrin output in group A compared to group C. We found a significant correlation between the amount of daily alcohol use and a decrease in lactoferrin output. There was a significant increase in GI and a tendency of PBI to increase in group A compared to group C. We demonstrated that chronic alcohol intoxication decreases SF and lactoferrin output. The decreased lactoferrin output in persons chronically intoxicated by alcohol may be the result of lactoferrin exhaustion during drinking (due to its alcohol-related lower biosynthesis or higher catabolism) or to decreased function of neutrophils affected by the ethanol. The poorer periodontal state in alcohol dependent persons compared to controls may be a result of lower salivary flow and decreased protection of the oral cavity by lactoferrin.

Carbohydrate markers in colon carcinoma

Spontaneously mutated multiple oncogenes and/or tumor suppressor genes in colon epithelial cell and its progeny, may cause proliferation out of control and create benign colon neoplasm (colon polyp). If additional mutations involve genes responsible for cell adhesion and movement, aberrant epithelial cells may become malignant (colon cancer) and invade surrounding and remote tissues, creating secondary tumors called metastases. Incidence of colorectal cancer dramatically increases at 50–65 year of age. In Europe in 2006 colorectal cancer consisted 12.9% of all cancers and caused 207 400 deaths. To laboratory detection and monitoring of colon cancer are used tumor markers. Tumor markers are substances produced by the body in response to cancer, or by cancer tissue itself. Glycoconjugate markers for colon cancer include aberrant: mucins covering the surface of the colon epithelial cells, cadherins, selectins and Ig –like adhesion molecules mediating cell-cell adhesion, integrins and integral membrane proteoglycans responsible for adhesion of colon epithelial cells to extracellular matrix, glycoconjugate components of ECM, as well as lysosomal membrane glycoproteins and exoglycosidases. Detection of colon cancer at early non malignant stage is crucial in its prevention and eradication. As colon cancer is the effect of accumulation many somatic mutations in oncogens, supressors, mismatch repair genes and many genes responsible for posttranslational modifications of proteins, multidirectional approach should be applied for its detection. A glycobiological approach to diagnosis and treatment of colorectal cancer should be directed to detection changes in glycosylation accompanying every step of colon cancer progression, and correlation between changes in glycosylation and tumor progression.