TY - JOUR
T1 - Effect of melatonin on N-nitrosodiethylamine-induced hepatocarcinogenesis in rats with reference to biochemical circadian rhythms
AU - Dakshayani, K. B.
AU - Subramanian, P.
AU - Essa, M. Mohamed
PY - 2007/3
Y1 - 2007/3
N2 - Tumors and tumor-bearing hosts exhibit markedly altered circadian rhythms, which serve as markers in the early diagnosis and prognosis of cancer. Our study presents the effect of melatonin on circadian rhythms of lipid peroxides and antioxidants in N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. The circadian rhythm characteristics (acrophase, amplitude, and mesor) of thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) were markedly altered in NDEA-treated rats. Melatonin administration caused a significant increase in the amplitude and mesor values of antioxidants and a significant decrease in the mesor values of TBARS. Further delays in acrophase in NDEA-treated rats were reversed by melatonin administration. In conclusion, melatonin may exert its chemopreventive effect by its role as an antioxidant as well as by altering the circadian rhythm characteristics.
AB - Tumors and tumor-bearing hosts exhibit markedly altered circadian rhythms, which serve as markers in the early diagnosis and prognosis of cancer. Our study presents the effect of melatonin on circadian rhythms of lipid peroxides and antioxidants in N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. The circadian rhythm characteristics (acrophase, amplitude, and mesor) of thiobarbituric acid reactive substances (TBARS), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and reduced glutathione (GSH) were markedly altered in NDEA-treated rats. Melatonin administration caused a significant increase in the amplitude and mesor values of antioxidants and a significant decrease in the mesor values of TBARS. Further delays in acrophase in NDEA-treated rats were reversed by melatonin administration. In conclusion, melatonin may exert its chemopreventive effect by its role as an antioxidant as well as by altering the circadian rhythm characteristics.
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U2 - 10.1080/15376520500195798
DO - 10.1080/15376520500195798
M3 - Article
C2 - 20020974
AN - SCOPUS:33846958800
SN - 1537-6516
VL - 17
SP - 67
EP - 75
JO - Toxicology Mechanisms and Methods
JF - Toxicology Mechanisms and Methods
IS - 2
ER -
