The melatonin action on stromal stem cells within pericryptal area in colon cancer model under constant light.
Constant light (LL) is associated with high incidence of colon cancer. MLT supplementation was related to the significant control of preneoplastic patterns. We sought to analyze preneoplastic patterns in colon tissue from animals exposed to LL environment (14 days; 300 lx), MLT-supplementation (10mg/kg/day) and DMH-treatment (1,2 dimethylhydrazine; 125 mg/kg). Rodents were sacrificed and MLT serum levels were measured by radioimmunoassay. Our results indicated that LL induced ACF development (p < 0.001) with a great potential to increase the number of CD133(+) and CD68(+) cells (p < 0.05 and p < 0.001). LL also increased the proliferative process (PCNA-Li; p < 0.001) as well as decreased caspase-3 protein (p < 0.001), related to higher COX-2 protein expression (p < 0.001) within pericryptal colonic stroma (PCCS). However, MLT-supplementation controlled the development of dysplastic ACF (p < 0.001) diminishing preneoplastic patterns into PCCS as CD133 and CD68 (p < 0.05 and p < 0.001). These events were relative to decreased PCNA-Li index and higher expression of caspase-3 protein. Thus, MLT showed a great potential to control the preneoplastic patterns induced by LL.
Department of Pathology, Medical School of Ribeirão Preto, University of São Paulo, Ribeirão Preto, São Paulo 14049-900, Brazil. kannen71@yahoo.com.br
Vinicius
V
Kannen
Tassiana
T
Marini
Dalila L
DL
Zanette
Fernando T
FT
Frajacomo
Gyl E B
GE
Silva
Wilson A
WA
Silva
Sérgio B
SB
Garcia
D000818:Animals; D003106:Colon / Q000187:drug effects / Q000378:metabolism / Q000473:pathology / Q000528:radiation effects; D003110:Colonic Neoplasms / Q000209:etiology* / Q000473:pathology / Q000517:prevention & control*; D008027:Light / Q000009:adverse effects*; D008297:Male; D008550:Melatonin / Q000008:administration & dosage* / Q000097:blood / Q000502:physiology; D014411:Neoplastic Stem Cells / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D017154:Stromal Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology
D008550:Melatonin