Ethanol-induced changes in lipid peroxidation of enterocytes across the crypt-villus axis in rats.
BACKGROUND
Reactive oxygen species (ROS) have been implicated in the turnover of epithelial cells in the rat intestine. The metabolism of ethanol generates ROS, which are implicated in cellular injury, but the levels of lipid peroxidation in intestine in chronic alcoholism are unknown.


OBJECTIVE
To investigate the effects of ethanol ingestion on lipid peroxidation, and anti- and pro-oxidant enzyme systems in enterocytes across the crypt-villus axis in intestine.


METHODS
Wistar rats (90-100 g) were administered 1 mL of 30% ethanol daily for 39 days. Intestinal epithelial cells were isolated in fractions. Malondialdehyde levels, and activities of glutathione-S-transferase (GST), glutathione reductase (GR), superoxide dismutase (SOD) and catalase were determined in various cell fractions. Incorporation of H3-thymidine into DNA of enterocytes was also determined.


RESULTS
Lipid peroxidation was elevated by two- to three-folds in both villus and crypt cells in ethanol-fed animals compared to controls. The activities of GST and GR were four- to six-folds higher in villus tip cells compared to crypt base cells. The activities of SOD and catalase were five- to seven-fold higher in crypt base cells compared to villus tip cells. Ethanol feeding elevated the activities of SOD (76-190%) and catalase (20-150%) in enterocytes all along the crypt-villus axis compared to the controls. H3 thymidine incorporation into DNA of enterocytes was reduced by half in ethanol-fed rats compared to controls.


CONCLUSIONS
There is a gradient in the concentration of lipid peroxides in enterocytes across the crypt-villus axis, being high at the villus tip and low at the crypt base in the rat intestine. Ethanol feeding enhanced lipid peroxidation in both villus and crypt cells.
Kalra
Amandeep Kaur
AK
Department of Biochemistry, Punjab University, Chandigarh, 160 014, India.
Gupta
Shiffalli
S
Turan
Aasma
A
Mahmood
Safrun
S
Mahmood
Akhtar
A
D000818:Animals; D002374:Catalase / Q000378:metabolism; D020895:Enterocytes / Q000201:enzymology / Q000378:metabolism*; D000431:Ethanol / Q000633:toxicity*; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects*; D008315:Malondialdehyde / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism
D000431:Ethanol; D008315:Malondialdehyde; D002374:Catalase; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; D005982:Glutathione Transferase