Nicotine Metabolite Cotinine Research Articles

Mütterlicher Tabakkonsum lässt sich durch einfache Intervention des Kinderarztes reduzieren

Exposure to environmental tobacco smoke at home increases the risk for numerous diseases in childhood. In this study we asked if maternal tobacco consumption can be reduced by a written advice of the paediatrician. In a paediatrician's practice we recruited 40 mothers who smoked ten or more cigarettes per day according to their own statement. The paediatrician's intervention consisted in a short written advice to reduce tobacco consumption. At the beginning of the study and six weeks later we obtained urine samples of the mothers in order to measure the concentrations of the nicotine metabolite cotinine. A subgroup of the study population was informed about the initial concentration of cotinine, the other subgroup was not informed. Following the written advice of the paediatrician mothers reduced their consumption of tobacco products according to their own information as well as according to the concentrations of cotinine. Confronting mothers with their initial concentrations of cotinine was not found to be an additional factor reducing tobacco consumption. Maternal consumption of tobacco products can be reduced significantly by an advice of the paediatrician at least for a short time.

A therapeutic vaccine for nicotine dependence: Results of a phase I and a randomized phase II study

1008 Background: Tobacco consumption remains the most important avoidable cancer risk and smoking causes 90% of all lung cancers. The vast majority of cigarette smokers who try to quit ultimately fail because of high relapse rates. Clearly novel approaches are needed for the treatment and prevention of nicotine addiction. Cytos002-NicQb is a therapeutic vaccine that aims at induction of nicotine specific antibodies that neutralize nicotine in the blood and reduce nicotine uptake into the brain. In this way nicotine will loose its rewarding central effects. This should enable smokers to break their pattern of addiction and protect them from full relapse in case of occasional ‘slips’. Methods: Phase I: 40 healthy non smokers were included in a single center, randomized, placebo-controlled, parallel-group dose comparison study. Phase II: 300 smokers were included in a multicenter, randomized, double-blind, placebo-controlled efficacy study. Primary endpoint of the study is continuous abstinence from smoking in months 4, 5, and 6 after first vaccination. Continuous abstinence is monitored by self reporting, detection of the nicotine metabolite cotinine in urine samples and by detection of CO in exhaled air. Results: Phase I: Safety: In general, vaccination with NicQb was safe and well tolerated. Of the adverse events that were recorded, most were rated as mild (93%), few as moderate and none as severe. Local reactions were the most prominent side effects observed. Some subjects reported flu-like symptoms. Immunogenicity: All subjects immunized with NicQb showed significant anti-nicotine IgG titers (100% response rate). Phase II: Efficacy: Data will be available in Q2, 2005 and will be presented for the first time at the meeting. Conclusions: NicQb is safe, well tolerated and highly immunogenic. Neutralizing the addiction driving nicotine in cigarette smoke by vaccination of the smoker holds promise to significantly reduce avoidable incidents of cancer and other smoking related disease. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Cytos Biotechnology Cytos Biotechnology Chilka Ltd., Cytos Biotechnology

Racial differences in exposure and glucuronidation of the tobacco‐specific carcinogen 4‐(methylnitrosamino)‐1‐(3‐pyridyl)‐1‐butanone (NNK)

In the United States, Blacks who smoke cigarettes have a higher mean blood concentration of the nicotine metabolite cotinine than White smokers. It has not been determined whether there are racial differences in the exposure to the cigarette smoke carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and in the detoxification of NNK metabolites. A community-based cross-sectional survey of 69 Black and 93 White smokers was conducted in lower Westchester County, New York. Information on smoking and lifestyle habits was collected and urinary concentrations of several tobacco smoke biomarkers were compared, including the NNK metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronide (NNAL-Gluc). A frequency histogram and probit plot of NNAL-Gluc:NNAL ratios were constructed to determine slow and rapid glucuronidation phenotypes. The mean concentrations of total NNAL, urinary cotinine, plasma cotinine, and thiocyanate were significantly higher in Black men than in White men for each cigarette smoked. In women, the only biomarker that was significantly elevated in Blacks was plasma cotinine. A higher proportion of White versus Black women was categorized as "rapid" glucuronidators (two-tailed exact test, P = 0.03). In men, there were no significant differences in NNAL-Gluc:NNAL phenotypes. The higher rates of lung carcinoma in black men may be due in part to a higher level of exposure to tobacco smoke carcinogens.

No increased levels of the nicotine metabolite cotinine in smokers with schizophrenia

The prevalence of smoking cigarettes has repeatedly been found to be greater in schizophrenia as compared with other psychiatric patients and the general population. Patients with schizophrenia have been found to engage in heavy smoking and consumption of higher doses of nicotine, probably by deeper inhalation of cigarettes. The aim of the current study was to assess nicotine exposure through smoking by measuring urinary cotinine, the major nicotine metabolite, in a group of smokers from Greece of smokers with schizophrenia and smokers from the general population. Participants were current smokers and belonged to one of two groups: 35 patients with schizophrenia and 48 healthy controls matched in age, education, and gender. The quantitative analysis of cotinine, the major metabolite of nicotine, in urine samples was performed by a modified high performance liquid chromatography (HPLC). Patients with schizophrenia who smoke presented a significantly larger time interval between last cigarette smoked and urine sample collection, as well as a significantly higher average number of cigarettes consumed daily than normal smokers. Urinary cotinine levels of patients with schizophrenia who smoke did not significantly differ from that of normal smokers when adjusted for average number of cigarettes per day and time interval between last cigarette smoked and urine collection. These results suggest that patients with schizophrenia did not present higher nicotine exposure through smoking compared with smokers from the community. The pharmacokinetic or pharmacodynamic properties of nicotine, as well as patient medications of the patients may explain our findings.

Advances in analytical toxicology: the current role of liquid chromatography-mass spectrometry in drug quantification in blood and oral fluid.

This paper reviews procedures for quantification of drugs in the biosamples blood, plasma, serum, or oral fluid (saliva, etc.) using liquid chromatography coupled with single-stage or tandem mass spectrometry (LC-MS, LC-MS-MS). Such procedures are important prerequisites for competent toxicological judgment and consultation in clinical and forensic toxicology. They cover blood (plasma, serum) analysis of amphetamines and related designer drugs, anesthetics, anticonvulsants, benzodiazepines, opioids, serotonergic drugs, tricyclic antidepressants, neuroleptics, antihistamines, beta-blockers, muscle relaxants, and sulfonylurea-type antidiabetics, and oral fluid analysis of amphetamines and related designer drugs, cocaine, benzoylecgonine, codeine, morphine, enantiomers of methadone and its main metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), the nicotine metabolites cotinine and hydroxycotinine, and finally risperidone and its metabolite 9-hydroxyrisperidone. Basic information on the procedures is given in two tables and an example of quantification is illustrated in two figures. The pros and cons of such LC-MS procedures including sample work-up and ion suppression effects are critically discussed.

Occupational exposure of non-smoking restaurant personnel to environmental tobacco smoke in Finland.

Environmental tobacco smoke (ETS) exposure levels in different restaurant types in Finland were assessed before the National Tobacco Act restricting smoking in restaurants was activated. Exposure to ETS was determined by measuring nicotine in the breathing zone of non-smoking restaurant workers and by quantification of the nicotine metabolites cotinine and 3-hydroxycotinine in the urine of these workers during one whole work week. Altogether 23 workers from 15 restaurants were included in the study. The geometric mean (GM) breathing-zone nicotine level was 3.9 microg/m(3) (3.7 microg/m(3) in pubs, 1.4 microg/m(3) in dining restaurants, and 10.2 microg/m(3) in nightclubs). The GM cotinine and trans-3'-hydroxycotinine level in urine were 3.3 ng/mg((creatinine)) and 15.3 ng/mg((creatinine)), respectively. The exposure to ETS of restaurant workers in dining restaurants was clearly lower than that of workers in pubs and nightclubs as indicated by all ETS-markers used in the present study. During the work week, the cotinine and 3'-hydroxycotinine levels in urine of the study subjects increased. The correlation between breathing zone nicotine and urine cotinine and hydroxycotinine was 0.66 for both compounds. Post-shift cotinine and hydroxycotinine levels were not significantly higher than the pre-shift levels. If 9 ng cotinine/mg((creatinine)) is considered as the level above which heavy exposure has occurred, then this level was exceeded by 14 (approximately 60%) subjects at least once during the work week. Nicotine metabolite concentrations in the urine increased during the work week in 80% of the subjects, and the increase was especially noticeable for subjects working in both pubs and nightclubs. The study indicates that measures to restrict ETS exposure in restaurants are needed.

A simple high performance liquid chromatographic method for the quantification of total cotinine, total 3′-hydroxycotinine and caffeine in the plasma of smokers

A simple isocratic HPLC procedure has been developed for the quantification of caffeine and the nicotine metabolites cotinine, 3′-hydroxycotinine, cotinine glucuronide and 3′-hydroxycotinine glucuronide in the plasma of smokers. The glucuronide conjugates were determined indirectly via initial basic hydrolysis of the analyte sample followed by quantification of the resulting deconjugation product. Plasma was basified, extracted with dichloromethane, evaporated, the residue dissolved water and an aliquot part was analyzed by HPLC. The method utilized a Partisil-10 SCX cation-exchange column and an isocratic mobile phase of sodium phosphate buffer: methanol (92:8 v/v, 0.1 M, adjusted to pH 4.8 with triethylamine) at a flow rate of 1.5 ml/min. UV detection was at 254 nm. All solutes were separated with good resolution, and quantification was determined using an internal standard of N, N-diethylnicotinamide. The retention times were: caffeine 5.1 min, 3′-hydroxycotinine 7.2 min, N, N-diethylnicotinamide 9.5 min, and cotinine 15.5 min. Detection limits for caffeine, 3′-hydroxycotinine, cotinine, and total cotinine were 10 ng/ml; the detection limit for total 3′-hydroxycotinine was 20 ng/ml. The inter-day and intra-day variations for all analytes were between 1 and 8%. This analytical method is suitable for the determination of caffeine and nicotine metabolite levels in large numbers of clinical samples.

Application of liquid separation techniques to the determination of the main urinary nicotine metabolites

A rapid procedure for the analysis of the main nicotine metabolites (cotinine, trans-3′-hydroxycotinine) in urine has been worked out. The procedure includes isolation of nicotine and its metabolites from urine by means solid–liquid extraction technique using resin Amberlite XAD-2 and then quantitation by the use of thin-layer chromatography with densitometry (in reflection mode). GC–MS was applied to confirm the results obtained by TLC. The procedure was applied to the analysis of cotinine concentrations in urine samples taken from children living in Upper Silesia region (Poland). Among 444 investigated children we did not find cotinine almost in 60% but in 15% of this population, there were children who could have been exposed to cigarette smoke.

Increased levels of the nicotine metabolite cotinine in schizophrenic smokers compared to other smokers

The purpose of this study was to determine if schizophrenic patients self-administer more nicotine during cigarette smoking than nonschizophrenic subjects. Urinary cotinine, a nicotine metabolite, was measured in 20 schizophrenic patients and 20 nonschizophrenic subjects with similar smoking history. Schizophrenic patients had significantly higher urinary cotinine levels, suggesting that schizophrenics consume higher doses of nicotine, probably by deeper inhalation of cigarettes. Schizophrenic patients' higher dose of nicotine may target different receptors than those activated by the lower doses self-administered by most nonschizophrenic smokers. In particular, high doses may activate low-affinity alpha-7 nicotinic receptors, associated with deficits in sensory inhibition in schizophrenia.

Pharmacodynamic effects of cotinine in abstinent cigarette smokers

The nicotine metabolite cotinine was administered to abstinent cigarette smokers to determine whether it has pharmacologic activity as assessed by various physiologic and subjective measurements. By means of a randomized, double-blind, placebo-controlled counterbalanced-order design, subjects received cotinine base (30 mg) intravenously after 48 hours of abstinence from cigarette smoking. Serum cotinine concentrations increased to levels commonly achieved during daily cigarette smoking, whereas no change in serum nicotine concentration was observed. Cotinine compared with placebo produced subjective differences in self-reported ratings of restlessness, anxiety and tension, insomnia, sedation, and pleasantness. Cotinine had minimal effects on cardiovascular measurements. These findings indicate that cotinine is behaviorally active in the setting of cigarette abstinence at blood concentrations similar to those commonly achieved through daily cigarette smoking.

Meconium analysis to assess fetal exposure to nicotine by active and passive maternal smoking

We measured nicotine metabolites (cotinine and trans-3′-hydroxycotinine) in meconium of infants of passive or active smokers as a direct marker of fetal exposure to tobacco smoke. Meconium was collected from 55 infants whose mothers were nonsmokers, passive smokers, or light or heavy active smokers. Nicotine metabolite concentration (NMC) in meconium was analyzed by radioimmunoassay and gas chromatography–mass spectrometry. Radioimmunoassay showed the following mean meconium NMCs (in nanograms per milliliter); nonsmoker, 10.9; passive smoker, 31.6; light active smoker; 34.7, and heavy active smoker, 54.6. Analysis of available samples by gas chromatography–mass spectrometry confirmed the presence of cotinine. Correlation between meconium NMC and the degree of maternal smoking was 0.54 ( p <0.001). Meconium NMCs in infants of passive and active smokers were significantly higher than in those of nonsmokers ( p <0.05). Meconium NMC in passive smokers was not significantly different from that in light active smokers ( p >0.05). Thus exposure of the fetus to tobacco smoke is substantial, even by passive maternal smoking. Meconium analysis for nicotine metabolites may be useful for clinical and research purposes. (J P ediatr 1994;124:471-6)

Smoking and decreased fertilisation rates in vitro

To examine possible mechanisms for the association between cigarette smoking and reduced fertility, we have measured the concentration of the nicotine metabolite cotinine in ovarian follicular fluid collected at the time of oocyte recovery during treatment for in-vitro fertilisation. In a group of women in whom follicular fluid cotinine could not be detected (limit of accurate measurement 20 ng/ml) 116 oocytes were collected, of which 84 became fertilised (72%), whereas among women with cotinine concentration greater than 20 ng/ml 20/45 (44%) oocytes did so (p<0·01). The median fertilisation rates for individuals (range 1-8 eggs each) in the high and low cotinine groups were 57% and 75%, respectively (p<0·05). These findings suggest that infertile women should be advised to stop or reduce smoking generally, and especially before treatment by in-vitro fertilisation.

Failure to prevent nicotine addition in young people with diabetes.

The habit of smoking is usually acquired at a young age and it is particularly undesirable in individuals with diabetes. A study was carried out to assess objectively the prevalence of smoking in young patients with diabetes and whether younger age at onset of diabetes (implying exposure to health education) reduced the incidence of smoking. Ninety nine young adults with diabetes attending the routine clinic were studied using a structured interview and assay of a urinary nicotine metabolite (cotinine). Forty eight percent of the cohort were smoking (raised urinary cotinine), although only 31% admitted to smoking. Thirty eight percent of the patients with childhood onset diabetes, 56% of the adolescent onset, and 47% of the young adult onset patients were smoking. Smoking was not related to glycaemic control or body mass index. In conclusion, smoking is common in young patients with diabetes and is often denied. Conventional health education does not appear to prevent children and adolescents with diabetes from starting to smoke. Anti-smoking policies and health education must therefore be reinforced and improved.

Effects of nicotinic agonists on the NMDA receptor

The cholinergic nicotinic agonists (−)nicotine and lobeline were observed to partially inhibit whole-cell N-methyl- D-aspartate (NMDA)-induced response in rat cortical neurons in culture. In addition we found that (−)nicotine, (+)nicotine, and lobeline, but not the nicotine metabolite (−)cotinine nor acetylcholine, were able to displace [ 3H]dizocilpine ([ 3H]MK 801) binding in well-washed membranes obtained from rat brain. These results show that certain nicotinic agonists can interact with the NMDA receptor and block its function.

A study of tobacco carcinogenesis XLIV. Bioassay in AJ mice of some N-nitrosamines

The evaluation of the tumorigenic activity in A/J mouse lung of certain tobacco N-nitrosamines, namely 3-(methylnitrosamino)propionic acid (NMPA), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and 4-(methylnitrosamino)-4-(3-pyridyl)-butyric acid (iso-NNAC), had the following results (total dose in micromol per mouse/lung tumors per mouse): NMPA (200/7.1 +/- 2.9); NNK (2/15.7 +/- 4.1); iso-NNAC (200/0.24 +/- 0.43); saline control (0.2 +/- 0.4). The tumorigenic activity of NMPA was not surprising since its lower homologue, N-nitrososarcosine, as well as its higher homologue, 4-(methylnitrosamino)-butyric acid, are known carcinogens. The high tumorigenic activity of NNK in strain A/J mice confirms earlier findings as to its carcinogenic potency in rats and hamsters. The lack of tumorigenic activity of iso-NNAC supports the observation that the pyridyl rest adjacent to the nitrosamino group inhibits the activity of some tobacco-specific N-nitrosamines (TSNA). Iso-NNAC is most likely formed endogenously from the nicotine metabolites cotinine and 4-(methylamino)-4-(3-pyridyl)butyric acid.

Accumulation of nicotine in pancreatic islets and calcitonin-producing cells in mice and chicks demonstrated by micro- and whole-body autoradiography.

SUMMARY By autoradiographic methods, nicotine was shown to be specifically accumulated in the pancreatic islets in mice. The results also indicated a high accumulation of nicotine in the parafollicular cells of the thyroid in mice and an accumulation was also shown in the ultimobranchial glands in chicks. Like the parafollicular cells of the thyroid in mammals, the ultimobranchial glands of birds are known to produce calcitonin. Metabolic studies with nicotine in vitro and autoradiographic studies with the main nicotine-metabolite cotinine, indicated an accumulation of unchanged nicotine (not metabolites) in the cells. The results are discussed in view of the fact that biogenic amines have been shown to be operative in these endocrine organs. It is suggested that nicotine can share common transport and/or storage mechanisms with biogenic amines in the cells. An effect of nicotine on hormone storage and/or release may take place via an interference with aminergic mechanisms in the cells.

Effect of nicotine and nicotine metabolites on insulin secretion from rabbit pancreas pieces.

The effects of nicotine and the nicotine metabolites cotinine and γ–(3-pyridyl)-γ-oxobutyric acid on insulin secretion from rabbit pancreas pieces were studied with a radioimmunological method. High concentrations of nicotine inhibited a glucose (3.0 mg/ml) induced insulin secretion, while lower concentrations stimulated the secretion. The stimulating effect of nicotine was also demonstrated in a lower glucose concentration (0.6 mg/ml). A high concentration of cotinine stimulated the glucose induced insulin secretion, while inhibitory effects of cotinine were not observed. In further experiments it was shown that nicotine was not metabolised in the pancreas in vitro, thus the effect of nicotine on insulin secretion is not due to cotinine formation. Both the stimulatory and the inhibitory effects of nicotine as well as the stimulatory effect of cotinine were blocked by both atropine and hexamethonium. γ-(3-pyridyl)-γ-oxobutyric acid had no effect on the glucose induced insulin secretion. Several possibilit...

Effect of nicotine treatment on the metabolism of nicotine in the mouse liver in vitro.

14C‐nicotine was incubated with a 10000 × g supernatant fraction of liver homogenate from mice pretreated with nicotine for 3, 10 and 17 days respectively. The rate of metabolism was measured by the determination of the oxidative nicotine metabolite cotinine. After intraperitoneal injections of 5 mg/kg of nicotine three times daily for three days a 50% significant decrease in metabolism was observed. A 71% significant decrease in hepatic glycogen was also seen. Giving nicotine 27.8 and 24.5 mg/kg/24 hours in drinking water for 10 and 17 days respectively did not significantly change the metabolism or the hepatic glycogen levels.