Pro-oxidant activity and methionine metabolism in chronic alcohol abusers: relationship to alcohol withdrawal and folate administration.

AIM: The aim of this study was to investigate whether alcohol withdrawal and folate administration could play a role on redox balance and metionine metabolism in heavy drinkers. METHODS: The derivatives of reactive oxygen metabolites (d-ROMs), homocysteine, total thiols, vitamin B12 and folate were evaluated in a selected group of 40 consecutive chronic alcohol abusers by comparison with 44 healthy moderate drinkers, as controls. RESULTS: Before alcohol withdrawal, d-ROMs were significantly higher (p<0.0001) in heavy drinkers than in controls: 368.5 (254.8-718.6) U.CARR vs 245 (200.7-360) U.CARR, respectively, median with range. Plasma homocysteine were significantly higher in alcoholics than in moderate drinkers (p<0.0001): 18 (9.5-82.2) micromol/L vs 9.1 (4.9-19.6) micromol/L, respectively. Heavy drinkers also exhibited higher serum thiols than moderate drinkers (p<0.003): 605.8 (448.2-717.7) micromol/L vs 554.8 (508.3-658.4) micromol/L, respectively. The patients showed lower plasma folate than controls (p<0.0001): 4.1 (1.9-9.7) ng/mL vs 8.8 (5.0-8.4) ng/mL, respectively, but similar vitamin B12 levels: 487 (299-786) pg/mL 621 (243-894) pg/mL. A negative correlation between homocysteine and folate was observed before withdrawal in alcoholics (r=-0.4546, p<0.038). Both serum thiols (549.7 micromol/L, range 402.4-616.6 micromol/L) and homocysteinemia (6.6 micromol/L, range 2.9-18.5 micromol/L) were significantly decreased (p<0.0001 and p<0.022, respectively) after a week of alcohol withdrawal and folate administration. CONCLUSION: Our findings show that both enhanced pro-oxidant activity and a derangement of methionine metabolism can be observed in heavy drinkers before alcohol withdrawal and folate administration. Furthermore, folate seems to be a strong determinant of both plasma homocysteine and thiol concentrations.

Performance and clinical application of a new, fast method for the detection of hydroperoxides in serum.

BACKGROUND: Evidence has increased suggesting that a condition of oxidative stress, due to imbalance of oxidative/antioxidant systems, can produce alterations in important biological functions as a consequence of free radicals reactivity towards proteins, lipids, and DNA. Hence the possibility of accurately measuring the oxidative state in a biological system in a simple manner could be of fundamental importance for clinical diagnostics. METHODS: A new, spectrophotometric assay ("d-ROMs test", Diacron s.r.l., Grosseto, Italy), which allows the measurement of reactive oxygen metabolites derivatives, such as hydroperoxides, has been evaluated. RESULTS: The "d-ROMs test" showed good precision, accuracy and linearity. Mean serum d-ROMs above the normal range (344.5 +/- 68.3 U.CARR., mean +/- SD) were detected in a group of heavy drinkers, and well correlated with both g-GT (r=0.44, p<0.04) and MCV (r=0.73, p<0.000), usually considered as biochemical markers of alcohol abuse. CONCLUSIONS: The new test for the measurement of endogenous hydroperoxides proved to be simple, reliable, and cheap. Furthermore, it can be easily applied on automated analyzers. Then it could be used as an early index of oxidative damage, which precedes and partly contributes to degenerative process that affects cell membranes and other lipid containing structures.

Oxidative stress and a thrombophilic condition in alcoholics without severe liver disease.

BACKGROUND AND OBJECTIVES: The degree of oxidative stress and its association with a thrombophilic condition, if any, were investigated in alcoholics before the onset of severe liver disease. DESIGN AND METHODS: Reactive oxygen species and total antioxidant capacity were evaluated using two new kinetic spectrophotometric methods in a selected group of 45 consecutive chronic alcohol abusers and 42 apparently healthy moderate drinkers, used as controls. The hemostatic system was explored by detecting the plasma levels of prothrombin fragment 1+2 (F1+2) and thrombin-antithrombin complexes (TAT) with enzyme-linked immunosorbent assays, while D-dimer plasma levels were measured with a turbidimetric immunoassay. RESULTS: Reactive oxygen species were significantly higher (p<0.001) in heavy drinkers than in controls: 328.1 (143.4-847.2) U.CARR vs 250 (200.7-366.8) U.CARR, respectively. The total antioxidant capacity was similar in chronic alcohol abusers and in moderate drinkers: 360.2 (336.8-374.4) microMol HClO/mL vs 369 (362-378.4) microMol HClO/mL, respectively. All molecular markers of hemostatic system activation were significantly increased in chronic alcohol abusers in comparison with those in moderate drinkers, as follows: TAT: 2.5 (1.4-13) microg/L vs 1.5 (1-4.1) mocrog/L, respectively (p<0.001); F1+2: 1.7 (0.5-5.2) nMol/L vs 0.9 (0.4-1.1) nMol/L, respectively (p<0.01); D-dimer: 235.5 (208-462) ng/mL vs 163.5 (71-233) ng/mL, respectively (p<0.001). INTERPRETATION AND CONCLUSIONS: Our results suggest that oxidative stress and a thrombophilic condition can be observed in heavy drinkers without severe liver disease. The new test available for measuring reactive oxygen species in serum proved to be reliable and useful as an early marker of tissue damage.

Reactive oxygen metabolites and prooxidant status in children with Down's syndrome.

Children with Down's syndrome suffer many diseases among which cardiovascular diseases, increased susceptibility to infections, leukemia, endocrine alterations, immune defects, nutritional disturbance and mental retardation have clinical relevance. It has been suggested that the pathogenesis of Down's syndrome involves reactive oxygen species arising from a mutation in gene encoding, which disproportionately elevates superoxide dismutase activity. Reactive oxygen species and total antioxidant capacity were evaluated using two new spectrophotometric methods in a selected group of 40 children with Down's syndrome and in 20 apparently healthy children used as controls. Reactive oxygen species were significantly higher (p <0.05) in children with Down's syndrome than in controls: 452 (+/- 72) U.Carr vs. 270 (+/- 66) U.Carr respectively. Total antioxidant capacity was significantly higher (p <0.05) in controls than in children with Down's syndrome: 380 (+/- 52) micromol hypochlorous acid (HCLO)/ml vs. 281 (+/- 33) micromol HCLO/ml, respectively. In fact, thiol groups (sulfhydryl) were significantly higher (p <0.05) in controls than in children with Down's syndrome: 644 (+/- 78) micromol/l vs. 462 (+/- 54) micromol/l, respectively Our data show how to simply measure chemical indices of oxidative status in serum samples from children with Down's syndrome. We determined the plasmatic activities of reactive oxygen metabolites and oxidative defense molecules. Accumulated macromolecular damage may be one of the causes of some of the abnormalities that are considered part of the syndrome. Therefore, children with Down's syndrome have to cope with a significant prooxidant environment. Oxidative stress causes alterations such as atherosclerosis, early aging, immunological default and neurologic disorders in Down's syndrome patients. The new test available for measuring reactive oxygen species in serum proved to be reliable and useful as an early marker of tissue damage.

A simple test to monitor oxidative stress.

BACKGROUND: The role of oxygen free radicals is considered important in the development of cardiovascular disease. However, until recently determination of free radicals plasma levels and the effect of antioxidant therapy on these levels has been difficult. The aim of the study was to determine the oxidative stress and the effect of the antioxidant compound AR(D) Stenovit on this stress in normal subjects and patients with intermittent claudication after oral administration for one week. METHODS: A portable, free radicals (FRs) determination system (D-Roms test, Diacron, Grosseto, Italy) was used. This test is based on the ability of transition metals to catalyse in the presence of peroxides with formation of FRs which are trapped by an alchilamine. The alchilamine reacts forming a coloured radical detectable at 505 nm. The reagents utilised are the cromogen (R1, an alchilamine) and a pH 4.8 buffer (R2). Ten microl of hemolysis-free serum are to 1 ml of R2 and to 10 microl of R1. The sample is mixed, incubated (1 min; 37 degrees C) and read for optical density. After another minute, the sample is read again. The average delta A/min is multiplied by a K factor and calculated using serum with defined value. RESULTS: In normal subjects the mean (+/-SD) levels of free radicals were 312+/-49 U.CARR (Carratelli units) before treatment and 218+/-33 U.CARR after treatment (p<0.05). A decrease of at least 10% was detected in every subject. In patients with peripheral vascular disease the mean (+/-SD) levels of free radicals were 404+/-42 U.CARR before treatment and 278+/-33 U.CARR after treatment (p<0.02). A decrease of at least 15% was detected in every patient (medium value 31%). CONCLUSIONS: The D-Roms test provides a simple, inexpensive and practical method to identify subjects with a high level of oxidative stress and to demonstrate the effect of treatment. The compound AR(D) Stenovit is effective in reducing circulating free radicals. Its action on the progression of atherosclerotic disease should be assessed in future studies.