Theobromine

About: Theobromine is a research topic. Over the lifetime, 1137 publications have been published within this topic receiving 29723 citations. The topic is also known as: 3,7-Dimethylxanthine & Theobromin.

Two Distinct Pathways for Metabolism of Theophylline and Caffeine Are Coexpressed in Pseudomonas putida CBB5

Abstract: Pseudomonas putida CBB5 was isolated from soil by enrichment on caffeine. This strain used not only caffeine, theobromine, paraxanthine, and 7-methylxanthine as sole carbon and nitrogen sources but also theophylline and 3-methylxanthine. Analyses of metabolites in spent media and resting cell suspensions confirmed that CBB5 initially N demethylated theophylline via a hitherto unreported pathway to 1- and 3-methylxanthines. NAD(P)H-dependent conversion of theophylline to 1- and 3-methylxanthines was also detected in the crude cell extracts of theophylline-grown CBB5. 1-Methylxanthine and 3-methylxanthine were subsequently N demethylated to xanthine. CBB5 also oxidized theophylline and 1- and 3-methylxanthines to 1,3-dimethyluric acid and 1- and 3-methyluric acids, respectively. However, these methyluric acids were not metabolized further. A broad-substrate-range xanthine-oxidizing enzyme was responsible for the formation of these methyluric acids. In contrast, CBB5 metabolized caffeine to theobromine (major metabolite) and paraxanthine (minor metabolite). These dimethylxanthines were further N demethylated to xanthine via 7-methylxanthine. Theobromine-, paraxanthine-, and 7-methylxanthine-grown cells also metabolized all of the methylxanthines mentioned above via the same pathway. Thus, the theophylline and caffeine N-demethylation pathways converged at xanthine via different methylxanthine intermediates. Xanthine was eventually oxidized to uric acid. Enzymes involved in theophylline and caffeine degradation were coexpressed when CBB5 was grown on theophylline or on caffeine or its metabolites. However, 3-methylxanthine-grown CBB5 cells did not metabolize caffeine, whereas theophylline was metabolized at much reduced levels to only methyluric acids. To our knowledge, this is the first report of theophylline N demethylation and coexpression of distinct pathways for caffeine and theophylline degradation in bacteria.

Effects of caffeine, theophylline and theobromine on scheduled controlled responding in rats.

Abstract: 1 Rats were trained to respond under a variable interval 30 s (VI 30) schedule of food reinforcement. Caffeine (0.32-32 mg/kg), theophylline (1.0-56 mg/kg) and theobromine (10-320 mg/kg) in general produced dose-related decreases in operant responding. At relatively low doses, caffeine (1.0 mg/kg) and theophylline (3.2 mg/kg) produced slight but nonsignificant increases in VI 30 responding. 3 The rank order of potency for producing decreases in responding was caffeine greater than theophylline greater than theobromine. 4 Daily caffeine injections (32 mg/kg, i.p.) resulted in the development of caffeine tolerance. This tolerance was characterized by a 6 fold shift to the right in the caffeine dose-effect curve. Saline substitution for the 32.0 mg/kg caffeine maintenance dose resulted in a substantial decrease in responding.

Cocoa and human health.

Abstract: Cocoa is a dry, powdered, nonfat component product prepared from the seeds of the Theobroma cacao L. tree and is a common ingredient of many food products, particularly chocolate. Nutritionally, cocoa contains biologically active substances that may affect human health: flavonoids (epicatechin and oligomeric procyanidins), theobromine, and magnesium. Theobromine and epicatechin are absorbed efficiently in the small intestine, and the nature of their conjugates and metabolites are now known. Oligomeric procyanidins are poorly absorbed in the small intestine, but catabolites are very efficiently absorbed after microbial biotransformation in the colon. A significant number of studies, using in vitro and in vivo approaches, on the effects of cocoa and its constituent flavonoids have been conducted. Most human intervention studies have been performed on cocoa as an ingredient, whereas many in vitro studies have been performed on individual components. Approximately 70 human intervention studies have been carried out on cocoa and cocoa-containing products over the past 12 years, with a variety of endpoints. These studies indicate that the most robust biomarkers affected are endothelial function, blood pressure, and cholesterol level. Mechanistically, supporting evidence shows that epicatechin affects nitric oxide synthesis and breakdown (via inhibition of nicotinamide adenine di-nucleotide phosphate oxidase) and the substrate arginine (via inhibition of arginase), among other targets. Evidence further supports cocoa as a biologically active ingredient with potential benefits on biomarkers related to cardiovascular disease. However, the calorie and sugar content of chocolate and its contribution to the total diet should be taken into account in intervention studies.

The actions of dibutyryl cyclic adenosine 3′,5′‐monophosphate and methyl xanthines on pancreatic exocrine secretion

Abstract: 1. The effects of dibutyryl cyclic adenosine 3′,5′-monophosphate (dibutyryl cyclic AMP) and theophylline have been tested in the stimulated and unstimulated perfused cat pancreas. 2. Dibutyryl cyclic AMP (1·0 m M) elicited the secretion of water and electrolytes, but not of enzymes, from this preparation. The composition of this secretion was the same as that secreted in response to secretin. This response could be slightly potentiated by theophylline. 3. Theophylline, theobromine and caffeine all markedly potentiated submaximal secretin stimulation, the relative effectiveness of these methyl xanthines being the same as that observed in the inhibition of pure phosphodiesterase prepared from beef heart. 4. At high concentration, theophylline had two effects: it was capable of initiating electrolyte and water secretion alone (whilst having only a very small stimulatory effect on enzyme secretion); it also had an inhibitory effect on secretion stimulated maximally by secretin. 5. Thus it was easy to mimic the action of secretin, but not pancreozymin, using dibutyryl cyclic AMP and theophylline. This suggests that the action of secretin, but not that of pancreozymin, may be mediated through cyclic AMP. Further evidence is, however, needed before these conclusions can be made with confidence.