TY - JOUR
T1 - Effects of a single dose of menadione on the intestinal calcium absorption and associated variables
AU - Marchionatti, Ana M.
AU - Díaz de Barboza, Gabriela E.
AU - Centeno, Viviana A.
AU - Alisio, Arturo E.
AU - Tolosa de Talamoni, Nori G.
N1 - Funding Information:
This study was supported by grants from FONCYT (BID 1201/OC-AR PICT 98-05-03126), CONICET, UNLAR and SECYT (UNC), Argentina. Dr. Nori Tolosa de Talamoni is a member of the Investigator Career from the CONICET. Viviana Centeno is a recipient of a Fellowship from FONCYT.
PY - 2003/8/1
Y1 - 2003/8/1
N2 - The effect of a single large dose of menadione on intestinal calcium absorption and associated variables was investigated in chicks fed a normal diet. The data show that 2.5 μmol of menadione/kg of b.w. causes inhibition of calcium transfer from lumen-to-blood within 30 min. This effect seems to be related to oxidative stress provoked by menadione as judged by glutathione depletion and an increment in the total carbonyl group content produced at the same time. Two enzymes presumably involved in calcium transcellular movement, such as alkaline phosphatase, located in the brush border membrane, and Ca 2+- pump ATPase, which sits in the basolateral membrane, were also inhibited. The enzyme inhibition could be due to alterations caused by the appearance of free hydroxyl groups, which are triggered by glutathione depletion. Addition of glutathione monoester to the duodenal loop caused reversion of the menadione effect on both intestinal calcium absorption and alkaline phosphatase activity. In conclusion, menadione shifts the balance of oxidative and reductive processes in the enterocyte towards oxidation causing deleterious effects on intestinal Ca2+ absorption and associated variables, which could be prevented by administration of oral glutathione monoester.
AB - The effect of a single large dose of menadione on intestinal calcium absorption and associated variables was investigated in chicks fed a normal diet. The data show that 2.5 μmol of menadione/kg of b.w. causes inhibition of calcium transfer from lumen-to-blood within 30 min. This effect seems to be related to oxidative stress provoked by menadione as judged by glutathione depletion and an increment in the total carbonyl group content produced at the same time. Two enzymes presumably involved in calcium transcellular movement, such as alkaline phosphatase, located in the brush border membrane, and Ca 2+- pump ATPase, which sits in the basolateral membrane, were also inhibited. The enzyme inhibition could be due to alterations caused by the appearance of free hydroxyl groups, which are triggered by glutathione depletion. Addition of glutathione monoester to the duodenal loop caused reversion of the menadione effect on both intestinal calcium absorption and alkaline phosphatase activity. In conclusion, menadione shifts the balance of oxidative and reductive processes in the enterocyte towards oxidation causing deleterious effects on intestinal Ca2+ absorption and associated variables, which could be prevented by administration of oral glutathione monoester.
KW - Ca absorption
KW - Glutathione
KW - Hydroxyl groups
KW - Menadione
KW - Oxidative stress
UR - http://www.scopus.com/inward/record.url?scp=0041387439&partnerID=8YFLogxK
U2 - 10.1016/S0955-2863(03)00078-0
DO - 10.1016/S0955-2863(03)00078-0
M3 - Article
C2 - 12948877
AN - SCOPUS:0041387439
SN - 0955-2863
VL - 14
SP - 466
EP - 472
JO - Journal of Nutritional Biochemistry
JF - Journal of Nutritional Biochemistry
IS - 8
ER -