The influence of light on daily rhythm in hepatic drug metabolizing enzymes in rat

Nair, Vivek V; Casper, Regina C.

doi:10.1016/0024-3205(69)90033-2

Cited by 89 publications

(27 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Dietary antioxidants are known to induce liver weight increases in the hairless mouse and similar increases induced in other experimental animals have been shown to be associated with induction of mixed function oxidase activity (Chan et al, 1977;Gilbert and Goldberg, 1965). Further, effects of light on rhythmic levels of hepatic drug-metabolizing enzymes are known (Radzialowski and Bousquet, 1968;Nair and Casper, 1969). This might be particularly important should the photochemical theory prove to be valid.…”

Section: Predisposing and Moderating Factorsmentioning

confidence: 99%

Experimental Ultraviolet Light-Carcinogenesis

Black

Chan

1977

Photochem Photobiol

View full text Add to dashboard Cite

Section: Predisposing and Moderating Factorsmentioning

confidence: 99%

Experimental Ultraviolet Light-Carcinogenesis

Black

Chan

1977

Photochem Photobiol

View full text Add to dashboard Cite

“…Thus hexobarbital oxidase activity is 44% higher at 10 P.M than at 2 P.M. (Nair and Casper, 1969) and parallels a measurable in vivo variation in the duration of hexobarbital-induced sleeping time. Such fluctuations seem to be related to changes in the abundance of smooth endoplasmic reticulum (Chedid and Nair, 1972).…”

Section: 3 Dynamics Of Microsomesmentioning

confidence: 65%

“…Microsomal oxidases of the rat hepatic system display a diurnal rhythm in which higher activity is generally associated with periods of darkness (Radzialowski and Bousquet, 1967;Nair and Casper, 1969;lori et aI., 1971). Thus hexobarbital oxidase activity is 44% higher at 10 P.M than at 2 P.M. (Nair and Casper, 1969) and parallels a measurable in vivo variation in the duration of hexobarbital-induced sleeping time.…”

Section: 3 Dynamics Of Microsomesmentioning

confidence: 99%

Microsomal Oxidation and Insecticide Metabolism

Nakatsugawa

Morelli

1976

Insecticide Biochemistry and Physiology

View full text Add to dashboard Cite

“…18) Because there are significant circadian rhythms in enzyme activity, 19,20) renal function, 21,22) blood flow, 23) and protein binding, 24) the pharmacokinetics and pharmacodynamics of many drugs are affected by circadian variations. 25,26) DPD, a major catabolic enzyme of 5-FU, has been reported to exhibit a circadian rhythm, and the variations have been correlated with the efficacy and toxicity of 5-FU in experimental animals 6,7) and cancer patients.…”

Section: Discussionmentioning

confidence: 99%

CPT‐11 Alters the Circadian Rhythm of Dihydropyrimidine Dehydrogenase mRNA in Mouse Liver

Shimizu

Tamura

Yamada

et al. 2001

Japanese Journal of Cancer Research

View full text Add to dashboard Cite

Combination chemotherapy consisting of 5-fluorouracil (5-FU) and 7-ethyl-10-[4-(1-piperidino)-1-piperidino]carboxycamptothecin (CPT-11) is a promising regimen for gastrointestinal cancer. The circadian-dependent efficacy and toxicity of 5-FU are related to the circadian variation in the activity of dihydropyrimidine dehydrogenase (DPD), which is a rate-limiting enzyme in the pyrimidine catabolic pathway. To optimize the schedule of the CPT-11 plus 5-FU combination, we investigated the effect of CPT-11 on the circadian rhythm of DPD in vivo. In control mice, the DPD mRNA level in the liver was significantly higher at 14:00 than that at 02:00. After intravenous administration of CPT-11 (30 mg/kg) at 20:00, the circadian rhythm of the DPD mRNA level in the liver was no longer observed 18 h later (14:00), but it was unaffected 6 and 18 h later (at 14:00 and 02:00) when CPT-11 was given at 08:00. In addition, a dose-dependent lengthening of the period of the circadian rhythm of DPD was observed for 42 h after intravenous injection of CPT-11 at 20:00. The levels of DPD protein and activity at 21 h after administration of CPT-11 (at 17:00) were significantly higher than at 9 h (at 05:00). These results suggest that CPT-11 may influence the circadian rhythm of DPD at the transcriptional level. Modulation of the circadian rhythm of DPD by CPT-11 may be a factor in optimizing the combination of 5-FU and CPT-11.Key words: CPT-11 -Dihydropyrimidine dehydrogenase -Circadian rhythm 7-Ethyl-10-[4-(1-piperidino)-1-piperidino]carboxycamptothecin (CPT-11) is one of the most potent therapeutic agents for the treatment of solid tumors, including lung, colorectal, and cervical cancer, and malignant lymphoma, 1,2) and combination regimens of CPT-11 and 5-fluorouracil (5-FU) have recently been evaluated in metastatic colorectal cancer patients.3, 4) Combination chemotherapy consisting of CPT-11, 5-FU, and leucovorin has been reported to be well tolerated and to have greater efficacy than 5-FU alone for first-line metastatic colorectal cancer. 5)Dihydropyrimidine dehydrogenase (DPD) is the ratelimiting enzyme in 5-FU catabolism, and it has been found to exhibit circadian variation in experimental animals 6,7) and cancer patients. 8) A study in cancer patients treated with 5-FU showed an inverse relationship between DPD activity in peripheral blood mononuclear cells and the plasma concentration of 8) and the circadian variation in 5-FU toxicity in rats has been reported to be inversely correlated with the circadian variation in DPD activity. 9)The relevance of chronotherapy using 5-FU, folinic acid, and oxaliplatin was investigated in phase II trials in metastatic colorectal cancer patients. 10)The mechanisms regulating circadian rhythms in a variety of species have recently been clarified. In mammals, the suprachiasmatic nucleus (SCN) of the anterior hypothalamus has been shown to be a circadian pacemaker, 11) and the human and mouse homologues of the mammalian period gene, which plays a central role in circadian rhythms, have been iso...

show abstract

The influence of light on daily rhythm in hepatic drug metabolizing enzymes in rat

Cited by 89 publications

References 16 publications

Experimental Ultraviolet Light-Carcinogenesis

Experimental Ultraviolet Light-Carcinogenesis

Microsomal Oxidation and Insecticide Metabolism

CPT‐11 Alters the Circadian Rhythm of Dihydropyrimidine Dehydrogenase mRNA in Mouse Liver

Contact Info

Product

Resources

About