Exogenous folate ameliorates ethanol-induced brain hyperhomocysteinemia and exogenous ethanol reduces taurine levels in chick embryos.
The effects of exogenous ethanol and/or folic acid on endogenous homocysteine (HoCys) and SAM (S-adenosylmethionine)/SAH (S-adenosylhomocysteine) levels in chick brains were studied at 11 days of development. Embryonic EtOH (3.0 mmol/kg egg) exposure caused a 1.6-fold increase in brain HoCys levels and a 9-fold decrease in brain SAM/SAH levels as compared to controls (p<or=0.05). Brain HoCys and SAM/SAH levels returned to control values when injected with a mixture of EtOH and folic acid (3.0 mmol EtOH/kg egg and 34 mumol folic acid/kg egg). The effects of exogenous EtOH on the remethylation pathway, as measured by 10-formyltetrahydrofolate dehydrogenase (10-FTHF DH) activities, and the transsulfuration pathway, as measured by taurine levels, were studied at 18 days of development. A single dosage of EtOH (3.0 mmol/kg egg; E(0)) and two daily dosages of EtOH (E(0-1)) failed to influence brain and hepatic 10-FTHF DH activities when compared to controls. However, three daily dosages of EtOH (E(0-2)) caused approximately a two-fold increase in brain 10-FTHF DH activities and a three-fold increase in hepatic 10-FTHF DH activities as compared to controls (p<or=0.05). Three daily EtOH dosages (E(0-2)) caused reduced taurine levels in both brain and hepatic tissues (p<or=0.05). Meanwhile, a single EtOH dosage (E(0)), two daily EtOH dosages (E(0-1)), and three daily EtOH dosages (E(0-2)), caused reduced hepatic taurine levels as compared to controls (p<or=0.05).
Biology Department, Hillsdale College, Hillsdale, MI 49242-1205, USA.
Robert K
RK
Barnett
Stephanie L
SL
Booms
Tracy
T
Gura
Mara
M
Gushrowski
Robert R
RR
Miller
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002642:Chick Embryo / Q000187:drug effects* / Q000196:embryology / Q000378:metabolism; D000431:Ethanol / Q000633:toxicity*; D005492:Folic Acid / Q000494:pharmacology / Q000627:therapeutic use*; D020138:Hyperhomocysteinemia / Q000139:chemically induced* / Q000378:metabolism / Q000517:prevention & control*; D013654:Taurine / Q000378:metabolism*
D013654:Taurine; D000431:Ethanol; D005492:Folic Acid