Chronic low vitamin intake potentiates cisplatin-induced intestinal epithelial cell apoptosis in WNIN rats.
OBJECTIVE
To investigate if cisplatin alters vitamin status and if VR modulates cisplatin induced intestinal apoptosis and oxidative stress in Wistar/NIN (WNIN) male rats.


METHODS
Weanling, WNIN male rats (n = 12 per group) received adlibitum for 17 wk: control diet (20% protein) or the same with 50% vitamin restriction. They were then sub-divided into two groups of six rats each and administered cisplatin (2.61 mg/kg bodyweight) once a week for three wk or PBS (vehicle control). Intestinal epithelial cell (IEC) apoptosis was monitored by morphometry, Annexin-V binding, M30 cytodeath assay and DNA fragmentation. Structural and functional integrity of the villus were assessed by villus height/crypt depth ratio and activities of alkaline phosphatase, lys, ala-dipeptidyl amino-peptidase, respectively. To assess the probable mechanism(s) of altered apoptosis, oxidative stress parameters, caspase-3 activity, and expression of Bcl-2 and Bax were determined.


RESULTS
Cisplatin per se decreased plasma vitamin levels and they were the lowest in VR animals treated with cisplatin. As expected VR increased only villus apoptosis, whereas cisplatin increased stem cell apoptosis in the crypt. However, cisplatin treatment of VR rats increased apoptosis both in villus and crypt regions and was associated with higher levels of TBARS, protein carbonyls and caspase-3 activity, but lower GSH concentrations. VR induced decrease in Bcl-2 expression was further lowered by cisplatin. Bax expression, unaffected by VR was increased on cisplatin treatment. Mucosal functional integrity was severely compromised in cisplatin treated VR-rats.


CONCLUSIONS
Low intake of vitamins increases the sensitivity of rats to cisplatin and promotes intestinal epithelial cell apoptosis.
Vijayalakshmi
Bodiga
B
Department of Pathology, National Institute of Nutrition, Indian Council of Medical Research, Jamai Osmania, Hyderabad-500007, Andhra Pradesh, India.
Sesikeran
Boindala
B
Udaykumar
Putcha
P
Kalyanasundaram
Subramaniam
S
Raghunath
Manchala
M
D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001835:Body Weight / Q000187:drug effects; D053148:Caspase 3; D020169:Caspases / Q000032:analysis / Q000235:genetics; D002945:Cisplatin / Q000494:pharmacology*; D053938:DNA Fragmentation; D004032:Diet; D019587:Dietary Supplements; D005786:Gene Expression Regulation / Q000187:drug effects; D007413:Intestinal Mucosa / Q000737:chemistry / Q000166:cytology* / Q000187:drug effects*; D007583:Jejunum / Q000737:chemistry / Q000166:cytology / Q000187:drug effects; D008297:Male; D018384:Oxidative Stress / Q000187:drug effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000235:genetics; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014815:Vitamins / Q000008:administration & dosage* / Q000097:blood; D051028:bcl-2-Associated X Protein / Q000032:analysis / Q000235:genetics
D019253:Proto-Oncogene Proteins c-bcl-2; D017392:Thiobarbituric Acid Reactive Substances; D014815:Vitamins; D051028:bcl-2-Associated X Protein; D000469:Alkaline Phosphatase; C505410:Casp3 protein, rat; D053148:Caspase 3; D020169:Caspases; D002945:Cisplatin