Vitamin E (alpha-tocopherol) supplementation in diabetic rats: effects on the proximal colon.
BACKGROUND
Neuropathy is one of the complications caused by diabetes mellitus which is directly related to the gastrointestinal manifestations of the disease. Antioxidant substances, such as vitamin E, may play an important role in the reduction of the neurological damage caused by diabetes mellitus. The aim of the present study was to determine whether vitamin E (alpha-tocopherol) at different concentrations induces any effects on the morphology of the intestinal wall and intrinsic innervation in the proximal colon of diabetic rats.


METHODS
Thirty rats (90-day-old) were assigned to the following groups: N (normoglycemic), NE1 (normoglycemic supplemented with vitamin E 0.1%), NE2 (normoglycemic supplemented with vitamin E 2%), D (diabetic), DE1 (diabetic supplemented with vitamin E 0.1%), and DE2 (diabetic supplemented with vitamin E 2%). Animals received vitamin E supplementation for 120 days and were sacrificed when they were 210 days old. The proximal colon of each animal was subjected to histology to study the intestinal wall and goblet cells and processed for whole-mount preparations to morphoquantitatively determine the total myenteric population.


RESULTS
Supplementation with vitamin E significantly reduced glycemia and glycated hemoglobin values and preserved the number of myenteric neurons in group DE2, without affecting intestinal area or thickness of the intestinal wall or muscular tunic.


CONCLUSIONS
Vitamin E (2%) influenced the glycemic parameters and had a neuroprotective effect on the total myenteric population, but the morphometric characteristics of the intestinal wall were unaffected.
Roldi
Luciana P
LP
Department of Morphophysiological Sciences, Laboratory of Enteric Neurons, State University of Maringá, Brazil. patyroldi@hotmail.com
Pereira
Renata V F
RV
Tronchini
Eleandro A
EA
Rizo
Gabriela V
GV
Scoaris
Célia R
CR
Zanoni
Jacqueline N
JN
Natali
Maria R M
MR
D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D003106:Colon / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000178:diet therapy* / Q000473:pathology; D019587:Dietary Supplements; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000187:drug effects / Q000378:metabolism; D008297:Male; D009197:Myenteric Plexus / Q000187:drug effects / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome; D014810:Vitamin E / Q000008:administration & dosage*; D014815:Vitamins / Q000008:administration & dosage*
D001786:Blood Glucose; D006442:Glycated Hemoglobin; D014810:Vitamin E; D014815:Vitamins