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1.
Mayo Clin Proc ; 96(12): 3071-3085, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34579945

RESUMO

OBJECTIVE: To investigate the relations between caffeine-derived metabolites (methylxanthines) and plasma lipids by use of population-based data from 2 European countries. METHODS: Families were randomly selected from the general population of northern Belgium (FLEMENGHO), from August 12, 1985, until November 22, 1990, and 3 Swiss cities (SKIPOGH), from November 25, 2009, through April 4, 2013. We measured plasma concentrations (FLEMENGHO, SKIPOGH) and 24-hour urinary excretions (SKIPOGH) of 4 methylxanthines-caffeine, paraxanthine, theobromine, and theophylline-using ultra-high-performance liquid chromatography-tandem mass spectrometry. We used enzymatic methods to estimate total cholesterol, high-density lipoprotein cholesterol, and triglyceride levels and the Friedewald equation for low-density lipoprotein cholesterol levels in plasma. We applied sex-specific mixed models to investigate associations between methylxanthines and plasma lipids, adjusting for major confounders. RESULTS: In both FLEMENGHO (N=1987; 1055 [53%] female participants) and SKIPOGH (N=990; 523 [53%] female participants), total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels increased across quartiles of plasma caffeine, paraxanthine, and theophylline (total cholesterol levels by caffeine quartiles in FLEMENGHO, male participants: 5.01±0.06 mmol/L, 5.05±0.06 mmol/L, 5.27±0.06 mmol/L, 5.62±0.06 mmol/L; female participants: 5.24±0.06 mmol/L, 5.15±0.05 mmol/L, 5.25±0.05 mmol/L, 5.42±0.05 mmol/L). Similar results were observed using urinary methylxanthines in SKIPOGH (total cholesterol levels by caffeine quartiles, male participants: 4.54±0.08 mmol/L, 4.94±0.08 mmol/L, 4.87±0.08 mmol/L, 5.27±0.09 mmol/L; female participants: 5.12±0.07 mmol/L, 5.21±0.07 mmol/L, 5.28±0.05 mmol/L, 5.28±0.07 mmol/L). Furthermore, urinary caffeine and theophylline were positively associated with high-density lipoprotein cholesterol in SKIPOGH male participants. CONCLUSION: Plasma and urinary caffeine, paraxanthine, and theophylline were positively associated with plasma lipids, whereas the associations involving theobromine were less clear. We postulate that the positive association between caffeine intake and plasma lipids may be related to the sympathomimetic function of methylxanthines, mitigating the overall health-beneficial effect of caffeine intake.


Assuntos
Cafeína/efeitos adversos , Lipídeos/sangue , Adulto , Bélgica , Cafeína/sangue , Cafeína/metabolismo , Cafeína/urina , Colesterol/sangue , HDL-Colesterol/sangue , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Suíça , Espectrometria de Massas em Tandem , Teobromina/efeitos adversos , Teobromina/sangue , Teobromina/urina , Teofilina/efeitos adversos , Teofilina/sangue , Teofilina/urina , Triglicerídeos/sangue , Xantinas/efeitos adversos , Xantinas/sangue , Xantinas/urina
2.
Am J Clin Nutr ; 97(6): 1201-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23595874

RESUMO

BACKGROUND: Evidence from clinical studies has suggested that cocoa may increase high-density lipoprotein (HDL)-cholesterol concentrations. However, it is unclear whether this effect is attributable to flavonoids or theobromine, both of which are major cocoa components. OBJECTIVES: We investigated whether pure theobromine increases serum HDL cholesterol and whether there is an interaction effect between theobromine and cocoa. DESIGN: The study had a 2-center, double-blind, randomized, placebo-controlled, full factorial parallel design. After a 2-wk run-in period, 152 healthy men and women (aged 40-70 y) were randomly allocated to consume one 200-mL drink/d for 4 wk that contained 1) cocoa, which naturally provided 150 mg theobromine and 325 mg flavonoids [cocoa intervention (CC)], 2) 850 mg pure theobromine [theobromine intervention (TB)], 3) cocoa and added theobromine, which provided 1000 mg theobromine and 325 mg flavonoids [theobromine and cocoa intervention (TB+CC)], or 4) neither cocoa nor theobromine (placebo). Blood lipids and apolipoproteins were measured at the start and end of interventions. RESULTS: In a 2-factor analysis, there was a significant main effect of the TB (P < 0.0001) but not CC (P = 0.1288) on HDL cholesterol but no significant interaction (P = 0.3735). The TB increased HDL-cholesterol concentrations by 0.16 mmol/L (P < 0.0001). Furthermore, there was a significant main effect of the TB on increasing apolipoprotein A-I (P < 0.0001) and decreasing apolipoprotein B and LDL-cholesterol concentrations (P < 0.02). CONCLUSIONS: Theobromine independently increased serum HDL-cholesterol concentrations by 0.16 mmol/L. The lack of significant cocoa and interaction effects suggested that theobromine may be the main ingredient responsible for the HDL cholesterol-raising effect. This trial was registered at clinicaltrials.gov as NCT01481389.


Assuntos
Cacau/química , HDL-Colesterol/sangue , Teobromina/administração & dosagem , Adulto , Idoso , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Pressão Sanguínea/efeitos dos fármacos , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Flavonoides/administração & dosagem , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Teobromina/efeitos adversos
3.
N Z Vet J ; 55(3): 149-51, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17534419

RESUMO

CASE HISTORY: An adult male kea (Nestor notabilis) in good body condition was found dead at Aoraki/Mt Cook Village, in the Southern Alps of New Zealand. The bird had previously been involved in behavioural tests of problem-solving ability. CLINICAL AND PATHOLOGICAL FINDINGS: The bird had substantial subcutaneous and abdominal reserves of fat. The crop contained 20 g of what appeared to be dark chocolate; a conservative estimate of the dose of methylxanthines ingested by the bird was 250 mg/kg theobromine, 20 mg/kg caffeine and 3 mg/kg theophylline. Histopathological examination revealed acute degenerative changes to hepatocytes, renal tubules, and cerebrocortical neurons. DIAGNOSIS: Acute combination methylxanthine toxicity after opportunistic ingestion of chocolate. CLINICAL RELEVANCE: This is the first report of the pathological findings of methylxanthine toxicity in a wild parrot, and illustrates the need to ensure that kea are protected from the toxic by-products of human habitation, and the difficulties in ensuring this against a neophilic, inquisitive and innovative parrot.


Assuntos
Cacau/intoxicação , Papagaios , Xantinas/administração & dosagem , Xantinas/efeitos adversos , Animais , Animais Selvagens , Cafeína/administração & dosagem , Cafeína/efeitos adversos , Evolução Fatal , Masculino , Teobromina/administração & dosagem , Teobromina/efeitos adversos , Teofilina/administração & dosagem , Teofilina/efeitos adversos
4.
Folia Histochem Cytobiol ; 44(3): 207-11, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16977802

RESUMO

Even most commonly consumed beverages like tea, coffee, chocolate and cocoa contain methylxanthines, biogenic amines and polyphenols, among them catechins, that exhibit significant biological activity and might profoundly affect the organism homeostasis. We have previously shown that 400 mg of bitter chocolate or 6 mg of theobromine added to the daily diet of pregnant and afterwards lactating mice affected embryonic angiogenesis and caused bone mineralization disturbances as well as limb shortening in 4-weeks old offspring. The aim of the present study was the morphometric and functional evaluation of kidneys in the 4-weeks old progeny mice fed according to the protocol mentioned above. Progeny from the mice fed chocolate presented considerable morphometric abnormalities in the kidney structure, with the lower number of glomeruli per mm2 and their increased diameter. Moreover, higher serum creatinine concentration was observed in that group of offspring. No morphometric or functional irregularities were found in the progeny of mice fed theobromine. Abnormalities demonstrated in the offspring of mice fed chocolate are not related to its theobromine content. Consequently, identification of active compound(s) responsible for the observed effects is of vital importance.


Assuntos
Cacau/efeitos adversos , Rim/anormalidades , Rim/fisiologia , Lactação , Troca Materno-Fetal , Anormalidades Induzidas por Medicamentos/diagnóstico , Animais , Animais Recém-Nascidos , Animais Lactentes , Cacau/química , Creatinina/sangue , Feminino , Lactação/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Gravidez , Teobromina/administração & dosagem , Teobromina/efeitos adversos
5.
Pharmacotherapy ; 21(5): 647-51, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11349754

RESUMO

A 22-year-old man was hospitalized after unexplained seizure-like activity and unresponsiveness. A urine toxicology screen was negative for salicylates, acetaminophen, alcohol, and drugs of abuse. Medical history was insignificant with the exception of recent (within 2 wks) ingestion of Hydroxycut is a dietary supplement purported to be energy enhancing, muscle building, and fat burning. The agent contains ephedra alkaloids and caffeine, which are both central nervous system stimulants; the etiology of seizure was attributed to their consumption. Due to a significant number of reported adverse events, the United States Food and Drug Administration (FDA) proposed regulations for dietary supplements containing ephedra alkaloids and requested an independent review of case reports linked to these products. Because herbal products are not subject to the same rigorous FDA regulations required for prescription and over-the-counter products, consumers unknowingly risk adverse effects when taking these products. Questioning patients about consumption of herbal products should be part of routine medical visits.


Assuntos
Estimulantes do Sistema Nervoso Central/efeitos adversos , Citratos/efeitos adversos , Ephedra sinica , Convulsões/induzido quimicamente , Adulto , Cafeína/efeitos adversos , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/efeitos adversos , Efedrina/efeitos adversos , Humanos , Masculino , Fitoterapia , Ácidos Picolínicos/efeitos adversos , Preparações de Plantas , Polissacarídeos/efeitos adversos , Convulsões/psicologia , Teobromina/efeitos adversos , Teofilina/efeitos adversos
7.
Recurso na Internet em Inglês | LIS - Localizador de Informação em Saúde | ID: lis-2801

RESUMO

It presents data reported and results of carcinogenicity evaluation for humans and animals of coffee, tea, mate, methylxanthynes and methylglyoxal.


Assuntos
Testes de Carcinogenicidade , Toxicologia , Carcinógenos , Café/efeitos adversos , Chá/efeitos adversos , Cafeína/efeitos adversos , Teofilina/efeitos adversos , Teobromina/efeitos adversos , Aldeído Pirúvico/efeitos adversos
9.
Plant Foods Hum Nutr ; 51(3): 231-43, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9629863

RESUMO

Caffeine and theobromine are purine alkaloids widely consumed as stimulants and snacks in coffee and cocoa based foods and most often as part of ingredients in drugs. Man has enjoyed a long history of consumption of caffeine and theobromine. Recent interest in these two alkaloids, however, is centered on their potential reproductive toxicities. Caffeine and theobromine are now known to cross the placental and blood brain barrier thus potentially inducing fetal malformation by affecting the expression of genes vital in development. The developing fetus may not have developed enzymes for detoxification of these methylxanthine alkaloids via demethylation. There is a need, therefore, to protect the conceptus against 'insults' from teratogens of this nature. Apart from its reproductive toxicity, the presence of caffeine and theobromine in cocoa could limit its potentials as a nourishing food. This is an issue that needs to be addressed by nutritionists and the food industry at large. This paper discusses the natural sources, consumption and uses, toxicity and the major advances in the reproductive toxicology of caffeine and theobromine. The biosynthesis of these compounds in plants, metabolism in mammalian systems and the involvement of cytochrome P450 are reviewed and summarized. Evidence in favor of the toxicity of these compounds in experimental animals is presented with emphasis on the implications of these findings in humans. The paper concludes with a call for caution in the use of caffeine and theobromine pending further and more elaborate investigations.


Assuntos
Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Teobromina/efeitos adversos , Animais , Biotransformação , Cafeína/metabolismo , Cafeína/farmacocinética , Estimulantes do Sistema Nervoso Central/metabolismo , Estimulantes do Sistema Nervoso Central/farmacocinética , Feto/efeitos dos fármacos , Feto/metabolismo , Humanos , Teobromina/metabolismo , Teobromina/farmacocinética
10.
Cancer Causes Control ; 4(6): 559-63, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8280834

RESUMO

Data from a population-based study of newly diagnosed cases of prostate cancer (n = 362) and age-matched controls (n = 685) conducted in Utah (United States) between 1983 and 1986 were used to determine if cigarette smoking, alcohol, coffee, tea, caffeine, and theobromine were associated with prostate cancer risk. These factors were examined since their use differs in the Utah population, which is comprised predominantly of members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormon), from most other populations. Pack-years of cigarettes smoked, alcohol intake, and consumption of alcohol, coffee, tea, and caffeine were not associated with prostate cancer risk. Compared with men with very low levels of theobromine intake, older men consuming 11 to 20 and over 20 mg of theobromine per day were at increased risk of prostate cancer (odds ratio [OR] for all tumors = 2.06, 95 percent confidence interval [CI] = 1.33-3.20, and OR = 1.47, CI = 0.99-2.19, respectively; OR for aggressive tumors = 1.90, CI = 0.90-3.97, and OR = 1.74, CI = 0.91-3.32, respectively). We present biological mechanisms for a possible association between prostate cancer and theobromine. This finding needs further exploration in studies with a wider range of theobromine exposures and more men with aggressive tumors.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Cafeína/efeitos adversos , Café/efeitos adversos , Neoplasias da Próstata/etiologia , Fumar/efeitos adversos , Chá/efeitos adversos , Teobromina/efeitos adversos , Idoso , Estudos de Casos e Controles , Cristianismo , Humanos , Masculino , Análise por Pareamento , Pessoa de Meia-Idade , Razão de Chances , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/epidemiologia , Fatores de Risco , Utah/epidemiologia
11.
Arukoru Kenkyuto Yakubutsu Ison ; 27(2): 168-79, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1586288

RESUMO

Effects of cocoa and its main CNS active constituent methylxanthine theobromine as well as caffeine were evaluated by ambulatory activity, and discrete lever-press and shuttle avoidance in mice. Cocoa (1 g/kg p.o.) and theobromine (10 mg/kg p.o.) significantly increased ambulatory activity. However, the other doses of cocoa and theobromine had no effect on the ambulatory activity. Caffeine increased ambulatory activity with the maximum action at 30 mg/kg p.o. Furthermore, cocoa (0.1, 0.3 and 1 g/kg), theobromine (3, 10, 30 and 100 mg/kg) and caffeine (3, 10, 30 and 100 mg/kg) enhanced the ambulation-increasing effect of methamphetamine (2 mg/kg s.c.). The ambulation-increasing effect of cocaine (20 mg/kg s.c.) was also enhanced by cocoa (1 g/kg), theobromine (10, 30 and 100 mg/kg) and caffeine (10, 30 and 100 mg/kg). On the other hand, comparatively higher doses of theobromine and caffeine disrupted the well established avoidance response. Thus, the avoidance rate was significantly decreased by theobromine (100 mg/kg and more) and caffeine (30 mg/kg and more) under the lever-press situation, and by theobromine (100 mg/kg and more) and caffeine (100 mg/kg) under the shuttle situation. These dose effect relationships revealed that cocoa contains about 1% theobromine. The present results indicate that we may receive the CNS action of theobromine through consumption of theobromine-containing foodstuffs or beverages in our every day life.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Cacau/efeitos adversos , Atividade Motora/efeitos dos fármacos , Teobromina/efeitos adversos , Animais , Cafeína/efeitos adversos , Masculino , Camundongos , Camundongos Endogâmicos
14.
Int J Epidemiol ; 18(3): 626-33, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2681017

RESUMO

The relationship between methylxanthine intake (caffeine, theobromine and theophylline) and risk of benign proliferative epithelial disorders (BPED) of the breast was examined in a case-control study conducted in Adelaide, South Australia. The study involved 383 cases with biopsy-confirmed BPED, 192 controls whose biopsy did not show epithelial proliferation, and 383 unbiopsied community controls individually matched to cases on age and area of residence. Overall, there was relatively little variation in risk of BPED with total methylxanthine intake, or with intake of caffeine or theophylline, while there was a positive association between theobromine intake and risk of BPED, but only when cases were compared with biopsy controls. Total methylxanthine intake was positively associated with risk of BPED showing severe atypia, but the trend in risk was statistically significant only when community controls formed the comparison group. These data do not provide strong support for an association between methylxanthine intake and risk of BPED.


Assuntos
Doença da Mama Fibrocística/induzido quimicamente , Xantinas/efeitos adversos , Adolescente , Adulto , Idoso , Biópsia , Mama/patologia , Cafeína/efeitos adversos , Estudos de Casos e Controles , Feminino , Doença da Mama Fibrocística/epidemiologia , Doença da Mama Fibrocística/patologia , Humanos , Pessoa de Meia-Idade , Risco , Austrália do Sul/epidemiologia , Teobromina/efeitos adversos
16.
Eur J Clin Pharmacol ; 11(3): 181-92, 1977 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-852496

RESUMO

A survey of tolerance of a drug, determined in private practice under "naturalistic" conditions by 591 physicians, and involving 22277 patients is presented. The procedure used in private practice to gather systematic information about reactions to the drug involved a system of data sheets with detachable cards for optical reading and computer analysis. The survey was conducted under the responsiblity at regional level of a team of scientific coordinators-hospital pharmacologists and poison control centres. Possible side effects were noticed in 13,82% of patients, a figure similar to known nocebo reactions. Tolerance was significantly related to sex, age, weight, geographical area, duration of treatment, association with other durgs and therapeutic result. When related to individual physicians, the overall number of side effects and the frequency of three of them in particular did not follow a binomial distribution; the rate of adverse reactions was significantly related to the number of years of practice of the physicians.


Assuntos
Ácidos Nicotínicos/efeitos adversos , Teobromina/análogos & derivados , Adulto , Fatores Etários , Idoso , Peso Corporal , Combinação de Medicamentos , Tratamento Farmacológico , Feminino , França , Humanos , Sistemas de Informação , Masculino , Métodos , Pessoa de Meia-Idade , Mortalidade , Ácidos Nicotínicos/administração & dosagem , Pacientes , Médicos , Prática Privada , Registros , Fatores Sexuais , Estatística como Assunto , Teobromina/administração & dosagem , Teobromina/efeitos adversos , Fatores de Tempo
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