PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 14616429-0 2003 Effects of caffeine intake on the pharmacokinetics of melatonin, a probe drug for CYP1A2 activity. Melatonin 54-63 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 82-88 14616429-1 2003 AIMS: The aim of this study was to assess the influence of concomitant caffeine intake on the pharmacokinetics of oral melatonin, a probe drug for CYP1A2 activity. Melatonin 119-128 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 147-153 14616429-7 2003 CONCLUSION: The results of this study revealed a pronounced effect of caffeine on the bioavailability of orally given melatonin, most probably due to inhibition of CYP1A2 activity. Melatonin 118-127 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 164-170 11703563-9 2001 Molecular modelling analysis revealed that melatonin had a high area/depth(2) ratio, displayed characteristics of CYP1A2 substrates and could be readily accommodated into the human CYP1A2 active site in a position favouring 6-hydroxylation. Melatonin 43-52 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 114-120 12906366-0 2003 Caffeine raises the serum melatonin level in healthy subjects: an indication of melatonin metabolism by cytochrome P450(CYP)1A2. Melatonin 26-35 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 104-127 12906366-0 2003 Caffeine raises the serum melatonin level in healthy subjects: an indication of melatonin metabolism by cytochrome P450(CYP)1A2. Melatonin 80-89 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 104-127 12035944-1 2002 Melatonin (MT) is metabolized in the liver by cytochrome P450 (CYP) 1A2 but its importance for the metabolic process has not been fully elucidated. Melatonin 0-9 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 46-71 12035944-2 2002 Therefore, the objective of this investigation was to study whether patients with different CYP1A2 activity would have different nocturnal serum MT levels. Melatonin 145-147 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 92-98 11703563-9 2001 Molecular modelling analysis revealed that melatonin had a high area/depth(2) ratio, displayed characteristics of CYP1A2 substrates and could be readily accommodated into the human CYP1A2 active site in a position favouring 6-hydroxylation. Melatonin 43-52 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 181-187 11317475-7 2001 CONCLUSIONS: Our results strongly suggest that 6-hydroxylation, the main metabolic pathway of melatonin, is mediated mainly, but not exclusively, by CYP1A2, the high-affinity enzyme involved in melatonin metabolism, confirming the observation that a single oral dose of fluvoxamine increases nocturnal serum melatonin levels in healthy subjects. Melatonin 94-103 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 149-155 11452239-0 2001 Orally given melatonin may serve as a probe drug for cytochrome P450 1A2 activity in vivo: a pilot study. Melatonin 13-22 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 53-72 11452239-1 2001 BACKGROUND: Melatonin is a hormone that is metabolized by cytochrome P450 (CYP) 1A2 to its main primary metabolite 6-hydroxymelatonin. Melatonin 12-21 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 58-83 11452239-2 2001 We therefore evaluated the utility of oral melatonin as a marker of hepatic CYP1A2 activity. Melatonin 43-52 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 76-82 11452239-3 2001 METHODS: Twenty-five milligrams of melatonin was given at 9:30 am to 12 healthy Swedish volunteers, who had previously been phenotyped for CYP1A2 with caffeine. Melatonin 35-44 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 139-145 11452239-9 2001 CONCLUSION: Melatonin might be developed as an alternative to caffeine as a probe drug for CYP1A2 phenotyping. Melatonin 12-21 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 91-97 11270913-4 2001 Melatonin was found to be almost exclusively metabolized by CYP1A2 to 6-hydroxymelatonin and N-acetylserotonin with a minimal contribution of CYP2C19. Melatonin 0-9 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 60-66 11317475-7 2001 CONCLUSIONS: Our results strongly suggest that 6-hydroxylation, the main metabolic pathway of melatonin, is mediated mainly, but not exclusively, by CYP1A2, the high-affinity enzyme involved in melatonin metabolism, confirming the observation that a single oral dose of fluvoxamine increases nocturnal serum melatonin levels in healthy subjects. Melatonin 194-203 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 149-155 11317475-7 2001 CONCLUSIONS: Our results strongly suggest that 6-hydroxylation, the main metabolic pathway of melatonin, is mediated mainly, but not exclusively, by CYP1A2, the high-affinity enzyme involved in melatonin metabolism, confirming the observation that a single oral dose of fluvoxamine increases nocturnal serum melatonin levels in healthy subjects. Melatonin 194-203 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 149-155 11317475-8 2001 Furthermore, the results indicate that there is a potential for interaction with drugs metabolised by CYP1A2 both at physiological levels and after oral administration of melatonin, while CYP2C19 and CYP2C9 are assumed to be less important. Melatonin 171-180 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 102-108 34575512-7 2021 The presence of CAP decreases the absorption of melatonin and increases its catabolism into 6-hydroxylation by the cytochrome P450 enzyme CYP1A2. Melatonin 48-57 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 138-144 10877005-0 2000 Fluvoxamine but not citalopram increases serum melatonin in healthy subjects-- an indication that cytochrome P450 CYP1A2 and CYP2C19 hydroxylate melatonin. Melatonin 47-56 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 114-120 35338582-0 2022 Evaluation of CYP1A2 activity: Relationship between the endogenous urinary 6-hydroxymelatonin to melatonin ratio and paraxanthine to caffeine ratio in dried blood spots. Melatonin 97-106 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 14-20 25553845-9 2015 Decreased CYP 1A2 activity, genetically determined or from concomitant medication, can slow metabolism, with loss of variation in melatonin level and loss of effect. Melatonin 130-139 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 10-17 33652180-0 2021 Third-hand smoke exposure is associated with abnormal serum melatonin level via hypomethylation of CYP1A2 promoter: Evidence from human and animal studies. Melatonin 60-69 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 99-105 33652180-11 2021 And the hub-site located on the CYP1A2 promoter was identified, which mediated the association between THS and decreased melatonin-level. Melatonin 121-130 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 32-38 31658882-1 2020 As an important member of cytochrome P450 (CYP) enzymes, human CYP1A2 is associated with the metabolism of caffeine and melatonin and the activation of precarcinogens. Melatonin 120-129 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 63-69 28070878-4 2017 It is mainly metabolized by CYP1A2 in human so that herbs/foods containing cytochrome P450 (CYP) inhibitors can affect pharmacokinetics of melatonin. Melatonin 139-148 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 28-34 21385053-13 2011 CONCLUSION: The low or even absent expression of CYP1A1 or CYP1A2 in breast cancer specimens suggested that melatonin might be involved in cell cycle arrest. Melatonin 108-117 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 59-65 26158279-7 2015 In vitro analysis involving several melatonin products showed product-dependent inhibition of CYP1A2, CYP2C19 and CYP3A7. Melatonin 36-45 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 94-100 24732412-2 2014 Drugs were selected based not only on the knowledge that the 6-hydroxylation of exogenous melatonin, its principal pathway of metabolism, is mainly mediated by hepatic CYP1A2, but also on the likelihood of the drug being concurrently administered with melatonin. Melatonin 90-99 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 168-174 24732412-4 2014 Of the drugs screened, only the potent CYP1A2 inhibitor 5-methoxypsoralen impaired the 6-melatonin hydroxylation at pharmacologically relevant concentrations, and is likely to lead to clinical interactions; diazepam, tamoxifen and acetaminophen (paracetamol) did not impair the metabolic conversion of melatonin to 6-sulphatoxymelatonin at concentrations attained following therapeutic administration. Melatonin 89-98 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 39-45 22823064-0 2013 CYP1A2 polymorphisms in slow melatonin metabolisers: a possible relationship with autism spectrum disorder? Melatonin 29-38 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 0-6 22823064-3 2013 We hypothesise that the disappearing effectiveness is associated with slow metabolisation of melatonin because of a single nucleotide polymorphism (SNP) of CYP1A2. Melatonin 93-102 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 156-162 17003850-1 2006 The metabolism of melatonin to 6-sulphatoxymelatonin (aMT6S) and N-acetylserotonin (NAS) is catalyzed by cytochrome-P450 (CYP) isozymes CYP1A2 and CYP2C19 respectively. Melatonin 18-27 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 136-142 20576063-13 2010 As melatonin is metabolised in the liver almost exclusively by cytochrome P450 enzyme CYP1A2, this slow melatonin metabolism is probably due to decreased activity/inducibility of CYP1A2. Melatonin 3-12 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 86-92 20576063-13 2010 As melatonin is metabolised in the liver almost exclusively by cytochrome P450 enzyme CYP1A2, this slow melatonin metabolism is probably due to decreased activity/inducibility of CYP1A2. Melatonin 3-12 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 179-185 20576063-13 2010 As melatonin is metabolised in the liver almost exclusively by cytochrome P450 enzyme CYP1A2, this slow melatonin metabolism is probably due to decreased activity/inducibility of CYP1A2. Melatonin 104-113 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 86-92 20576063-13 2010 As melatonin is metabolised in the liver almost exclusively by cytochrome P450 enzyme CYP1A2, this slow melatonin metabolism is probably due to decreased activity/inducibility of CYP1A2. Melatonin 104-113 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 179-185 19919601-0 2010 Inhibition of procarcinogen-bioactivating human CYP1A1, CYP1A2 and CYP1B1 enzymes by melatonin. Melatonin 85-94 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 56-62 19919601-1 2010 Administration of melatonin to rodents decreases the incidence of tumorigenesis initiated by benzo[a]pyrene or 7,12-dimethylbenz[a]anthracene, which requires bioactivation by cytochrome P450 enzymes, such as CYP1A1, CYP1A2 and CYP1B1, to produce carcinogenic metabolites. Melatonin 18-27 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 216-222 19919601-4 2010 Melatonin (3-300 microm) decreased 7-ethoxyresorufin O-dealkylation catalyzed by human hepatic microsomes and recombinant CYP1A1, CYP1A2 and CYP1B1, whereas it did not affect coumarin 7-hydroxylation catalyzed by hepatic microsomes or recombinant CYP2A6. Melatonin 0-9 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 130-136 19919601-7 2010 Additional experiments indicated that melatonin decreased benzo[a]pyrene hydroxylation catalyzed by hepatic microsomes and CYP1A2 but not by CYP1A1 or CYP1B1. Melatonin 38-47 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 123-129 18573860-10 2008 However, caffeine, melatonin, 9-cis-retinal, and estradiol, which are substrate for human CYP1A2, are not good substrates for dog CYP1A2. Melatonin 19-28 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 90-96 18490497-0 2008 The effect of oral contraceptives on the pharmacokinetics of melatonin in healthy subjects with CYP1A2 g.-163C>A polymorphism. Melatonin 61-70 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 96-102 18490497-6 2008 In conclusion, a significant inhibitory effect of OCs on the CYP1A2-catalyzed melatonin metabolism was seen; thereby, OC use can alter CYP1A2-phenotyping results. Melatonin 78-87 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 61-67 18490497-6 2008 In conclusion, a significant inhibitory effect of OCs on the CYP1A2-catalyzed melatonin metabolism was seen; thereby, OC use can alter CYP1A2-phenotyping results. Melatonin 78-87 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 135-141 17040215-0 2006 Effect of caffeine intake 12 or 24 hours prior to melatonin intake and CYP1A2*1F polymorphism on CYP1A2 phenotyping by melatonin. Melatonin 119-128 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 71-77 17040215-0 2006 Effect of caffeine intake 12 or 24 hours prior to melatonin intake and CYP1A2*1F polymorphism on CYP1A2 phenotyping by melatonin. Melatonin 119-128 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 97-103 17040215-1 2006 Earlier evidence suggests that melatonin is almost exclusively metabolised by CYP1A2 and could serve as a probe drug for CYP1A2 phenotyping. Melatonin 31-40 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 78-84 17040215-1 2006 Earlier evidence suggests that melatonin is almost exclusively metabolised by CYP1A2 and could serve as a probe drug for CYP1A2 phenotyping. Melatonin 31-40 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 121-127 17040215-2 2006 However, caffeine inhibits the metabolism of melatonin by CYP1A2 and dietary caffeine could be a potential confounder for the measurement of CYP1A2 activity with melatonin. Melatonin 45-54 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 58-64 17040215-2 2006 However, caffeine inhibits the metabolism of melatonin by CYP1A2 and dietary caffeine could be a potential confounder for the measurement of CYP1A2 activity with melatonin. Melatonin 162-171 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 141-147 17040215-6 2006 Also, individuals homozygous for the CYP1A2*1A allele had clearly higher 1.5 hr melatonin concentration compared with the *1F/*1F or the *1F/*1A genotypes. Melatonin 80-89 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 37-43 17040215-8 2006 Also, melatonin may be a sensitive probe to detect phenotypic differences with regard to CYP1A2*1F polymorphism. Melatonin 6-15 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 89-95 17040215-9 2006 Melatonin might be, thus, advantageous for CYP1A2 phenotyping compared to the standard probe caffeine. Melatonin 0-9 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 43-49 15824912-1 2005 OBJECTIVE: Polycyclic aromatic hydrocarbons in cigarette smoke induce cytochrome P450(CYP)1A2, which is involved in the hepatic metabolism of melatonin (MT). Melatonin 142-151 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 70-93 15616152-5 2005 CYP1A1, CYP1A2, and CYP1B1 all 6-hydroxylated MEL, with CYP2C19 playing a minor role. Melatonin 46-49 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 8-14 15616152-9 2005 These findings confirm the suggestion of others that CYP1A2 is probably the foremost hepatic P450 in the 6-hydroxylation of MEL and a single report that CYP1A1 is also able to mediate this reaction. Melatonin 124-127 cytochrome P450 family 1 subfamily A member 2 Homo sapiens 53-59