[13C]Aminopyrine and [13C]Caffeine Breath Test: Influence of Gender, Cigarette Smoking and Oral Contraceptives Intake

  title={[13C]Aminopyrine and [13C]Caffeine Breath Test: Influence of Gender, Cigarette Smoking and Oral Contraceptives Intake},
  author={M. S. Caubet and A. Laplante and J. M. Caill{\'e} and Jean Louis Brazier},
  journal={Isotopes in Environmental and Health Studies},
  pages={71 - 77}
Abstract The [13C]aminopyrine breath test ([13C]ABT) measures the global activity of cytochrome P450 in vivo and is a sensitive indicator of liver metabolic dysfunction. The present study aims to determine whether gender and cigarette smoking influence the results of [13C]ABT as well as to confirm the effect of oral contraceptive steroids (OCS) intake on this metabolic test. Hundred and ten healthy subjects, including men and women, smoker and non-smoker, women taking OCS or not, were… 
Interference of acute cigarette smoking with [13C]methacetin breath test
The curve of the cumulative 13C recovery on the cigarette smoking day appeared to be shifted downwards, and statistically significant differences relative to the control situation were found between the 24th and 75th minute following [13C]methacetin administration.
Influence of cigarette smoking on melatonin levels in man
This investigation shows that exogenous, but not endogenous (at night), serum MT levels are influenced by cigarette smoking, and implicate that interactions between exogenous MT, and substrates metabolized by CYP1A2, may differ in individuals before and after smoking abstinence.
Critical appraisal of 13C breath tests for microsomal liver function: aminopyrine revisited
Data suggest that both the 13C2‐aminopyrine and the13C‐methacetin breath test can play a role in assessing the capacity of the microsomal liver function and may be useful in the follow‐up of patients with chronic liver diseases.
Drug Interactions Involving 17α-Ethinylestradiol: Considerations Beyond Cytochrome P450 3A Induction and Inhibition.
It is widely acknowledged that drug-drug interactions (DDI) involving estrogen (17α-ethinylestradiol, EE)-containing oral contraceptives (OC) are important, and it is important to assess its projected (pre-Phase 1) or known therapeutic index and pharmacokinetic profile to enable the prioritization, design, and interpretation of NME-OC DDI studies.
Determination of urinary 13C-caffeine metabolites by liquid chromatography-mass spectrometry: the use of metabolic ratios to assess CYP1A2 activity.
Comparison between characteristic groups showed that labelled caffeine metabolic ratios were sensitive markers of changes in CYP1A2 activity, very difficult to eliminate even after a specific diet.
Objective: Polycyclic aromatic hydrocarbons in cigarette smoke induce cytochrome P450(CYP)1A2, which is involved in the hepatic metabolism of melato- nin (MT). This suggests that habitual smokers may
13C‐gastric emptying breath tests: Clinical use in adults and children
  • J. Keller, H. Hammer, B. Hauser
  • Medicine
    Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society
  • 2021
Evaluating the clinical use of 13C‐GEBT in adults and children, exploring available protocols, analytical methods, and essential prerequisites for test performance, as well as the role of GE measurements in the light of the current discussion on relevance of delayed GE for symptom generation.
[Clinically relevant breath tests in gastroenterological diagnostics--recommendations of the German Society for Neurogastroenterology and Motility as well as the German Society for Digestive and Metabolic Diseases].
The recommendations of the German Society of Neurogastroenterology and Motility and of theGerman Society of Digestive and Metabolic Diseases for clinically relevant H (2)- and (13)C-breath tests are presented.
Methods and functions: Breath tests.
  • B. Braden
  • Medicine
    Best practice & research. Clinical gastroenterology
  • 2009
Breath tests provide a valuable non-invasive diagnostic strategy to in vivo assess a variety of enzyme activities, organ functions or transport processes and enable the assessment of gastric bacterial Helicobacter pylori infection, gastric emptying, liver and pancreatic function as well as measurements of many other enzyme activities.
13C-breath tests: current state of the art and future directions.
  • B. Braden, B. Lembcke, W. Kuker, W. Caspary
  • Medicine
    Digestive and liver disease : official journal of the Italian Society of Gastroenterology and the Italian Association for the Study of the Liver
  • 2007
The stable isotope technique presents an elegant, non-invasive diagnostic tool promising further options of clinical applications and the quantification of liver function using hepatically metabolised 13C-substrates is clinically helpful in special indications.


Aminopyrine breath test: development of a 13C-breath test for quantitative assessment of liver function in humans.
The 13C-ABT is a simple and sensitive test to measure liver function and the use of the stable isotope 13C ensures the harmlessness of the test and the possibility to repeat it in a given patient.
Assessment of the cytochrome P-448 dependent liver enzyme system by a caffeine breath test
It is concluded that specifically labelled caffeine is a suitable and promising substrate for studying demethylation by breath analysis, Presumably, caffeine represents a safe and sensitive indicator of the activity of the cytochrome P-448 system.
13C breath tests for measurement of liver function
Theoretically, a combination of breath tests will enable the investigation of total liver functional capacity, and would be applicable in the prognosis of liver disease and also in the follow up assessment of liver transplant patients.
A study of gender-based cytochrome P4501A2 variability: a possible mechanism for the male excess of bladder cancer.
  • E. Horn, M. Tucker, +6 authors N. Caporaso
  • Medicine
    Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology
  • 1995
An effect of recent caffeine consumption is suggested, with heavy coffee drinkers having higher rates of caffeine clearance and women taking oral contraceptives having low CBT values.
Study of liver function tests using various stable isotope labelled compounds in liver cirrhosis
3 different stable isotope compounds which are metabolized in various sites of the liver were used to examine assessment methods which permit a precise expression of liver functions. The following 3
Inhibition of hepatic demethylation of aminopyrine by oral contraceptive steroids in humans
The data suggest that inhibition of hepatic demethylation of DAP by OCS is time dependent and reversible, and the extent of inhibition appears to be an individual characteristic of a given person.
Foreign compound metabolism capacity in man measured from metabolites of dietary caffeine.
The ratios of metabolites from dietary caffeine in spot urine samples offer ethical, non-invasive and reliable estimates of CYP1A2, NAT and XO, which are highly relevant for the bioactivation of potentially toxic compounds and the formation of oxygen radicals.
Use of caffeine metabolite ratios to explore CYP1A2 and xanthine oxidase activities
  • W. Kalow, B. Tang
  • Chemistry, Medicine
    Clinical pharmacology and therapeutics
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Caffeine was used as a metabolic probe to screen healthy subjects for their activities of two enzymes, deduced to be CYP1A2 (an inducible cytochrome P450) and xanthine oxidase, and both indexes showed a log normal distribution.
13C-phenylalanine and 13C-methacetin breath test to evaluate functional capacity of hepatocyte in chronic liver disease.
Both 13C-Phenylalanine Breath Test and Methacetin Breath Test are safe and easy tests to perform and both are able to discriminate the hepatic functional capacity between the different groups studied.
Induction of CYP1A2 activity by carbamazepine in children using the caffeine breath test.
The results suggest that carbamazepine induces the metabolism of caffeine by the CYP1A2 pathway in the children studied.