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.