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1.
PLoS One ; 19(4): e0294932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38603666

RESUMO

An important dietary source of physiologically active compounds, coffee also contains phenolic acids, diterpenes, and caffeine. According to a certain study, some coffee secondary metabolites may advantageously modify a number of anti-cancer defense systems. This research looked at a few coffee chemical structures in terms of edge locating numbers or edge metric size to better understand the mechanics of coffee molecules. Additionally, this research includes graph theoretical properties of coffee chemical structures. The chemicals found in coffee, such as caffeine, diterpene or cafestol, kahweol, chlorogenic, caffeic, gallotannins, and ellagitannins, are especially examined in these publications.


Assuntos
Diterpenos , Neoplasias , Humanos , Café/química , Cafeína , Dieta
2.
Molecules ; 29(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38611823

RESUMO

(1) Background: Diabetes is a common metabolic disease that seriously endangers human health. In the present study, we investigated the therapeutic effects of the active ingredient Eleutheroside B (EB) from the traditional Chinese medicine Eleutheroside on diabetes mellitus in a zebrafish model. Concomitant hepatic injury was also analysed, along with the study of possible molecular mechanisms using metabolomics technology. This work should provide some theoretical references for future experimental studies. (2) Methods: A zebrafish diabetes model was constructed by soaking in a 1.75% glucose solution and feeding a high-fat diet. The intervention drug groups were metformin (100 µg∙mL-1) and EB (50, 100, and 150 µg∙mL-1) via water-soluble exposure for 30 days. Glucose, TG, TC, LDL-C, and HDL-C were evaluated in different treatment groups. GLUT4 protein expression was also evaluated in each group, and liver injury was observed by HE staining. Metabolomics techniques were used to investigate the mechanism by which EB regulates endogenous markers and metabolic pathways during the development of diabetes. (3) Results: All EB treatment groups in diabetic zebrafish showed significantly reduced body mass index (BMI) and improved blood glucose and lipid profiles. EB was found to upregulate GLUT4 protein expression and ameliorate the liver injury caused by diabetes. Metabolomics studies showed that EB causes changes in the metabolic profile of diabetic zebrafish. These were related to the regulation of purine metabolism, cytochrome P450, caffeine metabolism, arginine and proline metabolism, the mTOR signalling pathway, insulin resistance, and glycerophospholipid metabolism. (4) Conclusions: EB has a hypoglycaemic effect in diabetic zebrafish as well as significantly improving disorders of glycolipid metabolism. The mechanism of action of EB may involve regulation of the mTOR signalling pathway, purine metabolism, caffeine metabolism, and glycerophospholipid metabolism.


Assuntos
Diabetes Mellitus , Glucose , Glucosídeos , Fenilpropionatos , Humanos , Animais , Metabolismo dos Lipídeos , Peixe-Zebra , Cafeína , Transportador de Glucose Tipo 4 , Serina-Treonina Quinases TOR , Glicerofosfolipídeos
3.
Appl Microbiol Biotechnol ; 108(1): 301, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639797

RESUMO

Water bodies are increasingly contaminated with a diversity of organic micropollutants (OMPs). This impacts the quality of ecosystems due to their recalcitrant nature. In this study, we assessed the removal of OMPs by spent mushroom substrate (SMS) of the white button mushroom (Agaricus bisporus) and by its aqueous tea extract. Removal of acesulfame K, antipyrine, bentazon, caffeine, carbamazepine, chloridazon, clofibric acid, and N, N-diethyl-meta-toluamide (DEET) by SMS and its tea was between 10 and 90% and 0-26%, respectively, in a 7-day period. Sorption to SMS particles was between 0 and 29%, which can thus not explain the removal difference between SMS and its tea, the latter lacking these particles. Carbamazepine was removed most efficiently by both SMS and its tea. Removal of OMPs (except caffeine) by SMS tea was not affected by heat treatment. By contrast, heat-treatment of SMS reduced OMP removal to < 10% except for carbamazepine with a removal of 90%. These results indicate that OMP removal by SMS and its tea is mediated by both enzymatic and non-enzymatic activities. The presence of copper, manganese, and iron (0.03, 0.88, and 0.33 µg L-1, respectively) as well as H2O2 (1.5 µM) in SMS tea indicated that the Fenton reaction represents (part of) the non-enzymatic activity. Indeed, the in vitro reconstituted Fenton reaction removed OMPs > 50% better than the teas. From these data it is concluded that spent mushroom substrate of the white button mushroom, which is widely available as a waste-stream, can be used to purify water from OMPs.


Assuntos
Agaricus , Ecossistema , Cafeína , Peróxido de Hidrogênio , Água , Chá , Carbamazepina
5.
Food Chem ; 448: 139138, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569407

RESUMO

Tea cream formed in hot and strong tea infusion while cooling deteriorates quality and health benefits of tea. However, the interactions among temporal contributors during dynamic formation of tea cream are still elusive. Here, by deletional recombination experiments and molecular dynamics simulation, it was found that proteins, caffeine (CAF), and phenolics played a dominant role throughout the cream formation, and the contribution of amino acids was highlighted in the early stage. Furthermore, CAF was prominent due to its extensive binding capacity and the filling complex voids property, and caffeine-theaflavins (TFs) complexation may be the core skeleton of the growing particles in black tea infusion. In addition to TFs, the unidentified phenolic oxidation-derived products (PODP) were confirmed to contribute greatly to the cream formation.


Assuntos
Cafeína , Camellia sinensis , Catequina , Simulação de Dinâmica Molecular , Chá , Chá/química , Cafeína/química , Cafeína/metabolismo , Camellia sinensis/química , Camellia sinensis/metabolismo , Camellia sinensis/crescimento & desenvolvimento , Catequina/química , Catequina/metabolismo , Biflavonoides/química , Biflavonoides/metabolismo , Fenóis/química , Fenóis/metabolismo , Manipulação de Alimentos , Temperatura Alta
6.
Nutrients ; 16(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542805

RESUMO

Caffeine (1,3,7-trimethylxanthine) is a widely consumed bioactive substance worldwide. Our recent study showed that a reduction in both reproduction and yolk protein production (vitellogenesis) caused by caffeine intake were improved by vitamin B12 supplementation, which is an essential co-factor in methionine metabolism. In the current study, we investigated the role of methionine in the reproduction of caffeine-ingested animals (CIAs). We assessed the effect of methionine metabolism on CIAs and found that caffeine intake decreased both methionine levels and essential enzymes related to the methionine cycle. Furthermore, we found that the caffeine-induced impairment of methionine metabolism decreased vitellogenesis and increased germ cell apoptosis in an LIN-35/RB-dependent manner. Interestingly, the increased germ cell apoptosis was restored to normal levels by methionine supplementation in CIAs. These results indicate that methionine supplementation plays a beneficial role in germ cell health and offspring development by regulating vitellogenesis.


Assuntos
Caenorhabditis elegans , Metionina , Animais , Metionina/farmacologia , Metionina/metabolismo , Cafeína/farmacologia , Cafeína/metabolismo , Apoptose , Células Germinativas , Racemetionina/metabolismo , Suplementos Nutricionais
7.
Planta Med ; 90(6): 426-439, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452806

RESUMO

Plants are an incredible source of metabolites showing a wide range of biological activities. Among these, there are the alkaloids, which have been exploited for medical purposes since ancient times. Nowadays, many plant-derived alkaloids are the main components of drugs used as therapy for different human diseases. This review deals with providing an overview of the alkaloids used to treat eye diseases, describing the historical outline, the plants from which they are extracted, and the clinical and molecular data supporting their therapeutic activity. Among the different alkaloids that have found application in medicine so far, atropine and pilocarpine are the most characterized ones. Conversely, caffeine and berberine have been proposed for the treatment of different eye disorders, but further studies are still necessary to fully understand their clinical value. Lastly, the alkaloid used for managing hypertension, reserpine, has been recently identified as a potential drug for ameliorating retinal disorders. Other important aspects discussed in this review are different solutions for alkaloid production. Given that the industrial production of many of the plant-derived alkaloids still relies on extraction from plants, and the chemical synthesis can be highly expensive and poorly efficient, alternative methods need to be found. Biotechnologies offer a multitude of possibilities to overcome these issues, spanning from genetic engineering to synthetic biology for microorganisms and bioreactors for plant cell cultures. However, further efforts are needed to completely satisfy the pharmaceutical demand.


Assuntos
Alcaloides , Oftalmopatias , Humanos , Alcaloides/farmacologia , Alcaloides/isolamento & purificação , Alcaloides/química , Oftalmopatias/tratamento farmacológico , Atropina/farmacologia , Pilocarpina , Plantas Medicinais/química , Cafeína/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Reserpina/farmacologia
8.
Nutrients ; 16(6)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38542677

RESUMO

This study examined the effect of creatine nitrate and caffeine alone and combined on exercise performance and cognitive function in resistance-trained athletes. In a double-blind, randomized crossover trial, twelve resistance-trained male athletes were supplemented with 7 days of creatine nitrate (5 g/day), caffeine (400 mg/day), and a combination of creatine nitrate and caffeine. The study involved twelve resistance-trained male athletes who initially provided a blood sample for comprehensive safety analysis, including tests for key enzymes and a lipid profile, and then performed standardized resistance exercises-bench and leg press at 70% 1RM-and a Wingate anaerobic power test. Cognitive function and cardiovascular responses were also examined forty-five minutes after supplementation. Creatine nitrate and caffeine that were co-ingested significantly enhanced cognitive function, as indicated by improved scores in the Stroop Word-Color Interference test (p = 0.04; effect size = 0.163). Co-ingestion was more effective than caffeine alone in enhancing cognitive performance. In contrast, no significant enhancements in exercise performance were observed. The co-ingestion of creatine nitrate and caffeine improved cognitive function, particularly in cognitive interference tasks, without altering short-term exercise performance. Furthermore, no adverse events were reported. Overall, the co-ingestion of creatine nitrate and caffeine appears to enhance cognition without any reported side effects for up to seven days.


Assuntos
Cafeína , Nitratos , Humanos , Masculino , Cafeína/farmacologia , Cognição , Creatina/farmacologia , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Exercício Físico , Nitratos/farmacologia
9.
Talanta ; 273: 125892, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38493609

RESUMO

In this study, NIR quantitative prediction model was established for sensory score and physicochemical components of different varieties and quality grades of Yuezhou Longjing tea. Firstly, L, a, b color factors and diffuse reflection spectral data are collected for each sample. Subsequently, the original spectrum is preprocessed. Three techniques for selecting variables, CARS, BOSS, and SPA, were utilized to extract optimal feature bands. Finally, the spectral data extracted from feature bands were fused with L, a and b color factors to build SVR and PLSR prediction models. enabling the rapid non-destructive discrimination of different varieties and grades of Yuezhou Longjing tea. The outcomes demonstrated that BOSS was the best variable selection technique for sensory score and the distinctive caffeine wavelengths, CARS, however, was the best variable selection technique for catechins distinctive wavelengths. Additionally, the middle-level data fusion-based non-linear prediction models greatly outperformed the linear prediction models. For the prediction models of sensory score, catechins, and caffeine, the relative percent deviation (RPD) values were 2.8, 1.6, and 2.6, respectively, suggesting the good predictive ability of the models. In conclusion, evaluating the quality of the five Yuezhou Longjing tea varieties using near-infrared spectroscopy and data fusion have proved as feasible.


Assuntos
Catequina , Espectroscopia de Luz Próxima ao Infravermelho , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Chá/química , Cafeína , Modelos Lineares , Algoritmos , Análise dos Mínimos Quadrados
10.
Int J Dev Neurosci ; 84(3): 251-261, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38469915

RESUMO

OBJECTIVE: The aim of this study is to evaluate whether exogenous melatonin (MEL) mitigates the deleterious effects of high-dose caffeine (CAF) administration in pregnant rats upon the fetal hippocampus. MATERIALS AND METHODS: A total of 32 adult Wistar albino female rats were divided into four groups after conception (n = 8). At 9-20 days of pregnancy, intraperitoneal (i.p.) MEL was administered at a dose of 10 mg/kg/day in the MEL group, while i.p. CAF was administered at a dose of 60 mg/kg/day in the CAF group. In the CAF plus MEL group, i.p. CAF and MEL were administered at a dose of 60 and 10 mg/kg/day, respectively, at the same period. Following extraction of the brains of the fetuses sacrificed on the 21st day of pregnancy, their hippocampal regions were analyzed by hematoxylin and eosin and Cresyl Echt Violet, anti-GFAP, and antisynaptophysin staining methods. RESULTS: While there was a decrease in fetal and brain weights in the CAF group, it was found that the CAF plus MEL group had a closer weight average to that of the control group. Histologically, it was observed that the pyramidal cell layer consisted of 8-10 layers of cells due to the delay in migration in hippocampal neurons in the CAF group, while the MEL group showed similar characteristics with the control group. It was found that these findings decreased in the CAF plus MEL group. CONCLUSION: It is concluded that high-dose CAF administration causes a delay in neurogenesis of the fetal hippocampus, and exogenous MEL is able to mitigate its deleterious effects.


Assuntos
Cafeína , Hipocampo , Melatonina , Fármacos Neuroprotetores , Ratos Wistar , Animais , Feminino , Melatonina/farmacologia , Melatonina/administração & dosagem , Hipocampo/efeitos dos fármacos , Gravidez , Cafeína/administração & dosagem , Cafeína/farmacologia , Ratos , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/administração & dosagem , Estimulantes do Sistema Nervoso Central/toxicidade , Estimulantes do Sistema Nervoso Central/administração & dosagem , Relação Dose-Resposta a Droga
11.
PeerJ ; 12: e16928, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38436002

RESUMO

Momordica cymbalaria Hook F. (MC), belonging to the family Cucurbitaceae, is a plant with several biological activities. This detailed, comprehensive review gathers and presents all the information related to the geographical distribution, morphology, therapeutic uses, nutritional values, pharmacognostic characters, phytochemicals, and pharmacological activities of MC. The available literature showed that MC fruits are utilized as a stimulant, tonic, laxative, stomachic, and to combat inflammatory disorders. The fruits are used to treat spleen and liver diseases and are applied in folk medicine to induce abortion and treat diabetes mellitus. The phytochemical screening studies report that MC fruits contain tannins, alkaloids, phenols, proteins, amino acids, vitamin C, carbohydrates, ß-carotenes, palmitic acid, oleic acid, stearic acid, α-eleostearic acid, and γ-linolenic acid. The fruits also contain calcium, sodium, iron, potassium, copper, manganese, zinc, and phosphorus. Notably, momordicosides are cucurbitacin triterpenoids reported in the fruits of MC. Diverse pharmacological activities of MC, such as analgesic, anti-inflammatory, antioxidant, hepatoprotective, nephroprotective, antidiabetic, cardioprotective, antidepressant, anticonvulsant, anticancer, antiangiogenic, antifertility, antiulcer, antimicrobial, antidiarrheal and anthelmintic, have been reported by many investigators. M. cymbalaria methanolic extract is safe up to 2,000 mg/kg. Furthermore, no symptoms of toxicity were found. These pharmacological activities are mechanistically interpreted and described in this review. Additionally, the microscopic, powder and physiochemical characteristics of MC tubers are also highlighted. In summary, possesses remarkable medicinal values, which warrant further detailed studies to exploit its potential benefits therapeutically.


Assuntos
Cucurbitaceae , Momordica , Feminino , Gravidez , Humanos , Compostos Fitoquímicos/farmacologia , Cafeína , Vitaminas
12.
Molecules ; 29(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38474530

RESUMO

Kombucha is a non-alcoholic beverage, that is increasingly used in the cosmetic industry. The available literature reports the positive effects of kombucha on the skin, in particular its antioxidant action. However, there is a lack of information on skin permeation and the accumulation of active ingredients showing such effects. Skin aging is largely dependent on oxidative stress, therefore in our study we assessed the ex vivo permeation of two types of kombucha (green and black tea) through porcine skin. The antioxidant activity (DPPH, ABTS, FRAP methods) and total polyphenol content of these extracts were determined before and after permeation testing. Moreover, the content of selected phenolic acids as well as caffeine was assessed. Skin permeation was determined using a Franz diffusion cell. The antioxidant activity of both Kombuchas was found to be high. In addition, gallic acid, chlorogenic acid, protocatechuic acid, coumaric acid, m-hydroxybenzoic acid, and caffeine were identified. A 24-h ex vivo study showed the permeation of some phenolic acids and caffeine and their accumulation in the skin. Our results confirm the importance of studying the skin permeation of what are still little known ingredients in cosmetic preparations. Evaluation of the accumulation of these ingredients can guarantee the efficacy of such preparations.


Assuntos
Antioxidantes , Cosméticos , Hidroxibenzoatos , Animais , Suínos , Antioxidantes/análise , Cafeína , Pele/química , Chá
13.
Nutrients ; 16(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474796

RESUMO

The ergogenic effects of acute caffeine intake on endurance cycling performance lasting ~1 h have been well documented in controlled laboratory studies. However, the potential benefits of caffeine supplementation in cycling disciplines such as cross-country/mountain biking have been rarely studied. In cross-country cycling, performance is dependent on endurance capacity, which may be enhanced by caffeine, but also on the technical ability of the cyclist to overcome the obstacles of the course. So, it is possible that the potential benefits of caffeine are not translated to cross-country cycling. The main objective of this study was to investigate the effects of acute caffeine intake, in the form of coffee, on endurance performance during a cross-country cycling time trial. Eleven recreational cross-country cyclists (mean ± SD: age: 22 ± 3 years; nine males and two females) participated in a single-blinded, randomised, counterbalanced and crossover experiment. After familiarisation with the cross-country course, participants completed two identical experimental trials after the ingestion of: (a) 3.00 mg/kg of caffeine in the form of soluble coffee or (b) 0.04 mg/kg of caffeine in the form of decaffeinated soluble coffee as a placebo. Drinks were ingested 60 min before performing a 13.90 km cross-country time trial over a course with eight sectors of varying technical difficulty. The time to complete the trial and the mean and the maximum speed were measured through Global Positioning System (GPS) technology. Heart rate was obtained through a heart rate monitor. At the end of the time trial, participants indicated their perceived level of fatigue using the traditional Borg scale. In comparison to the placebo, caffeine intake in the form of coffee significantly reduced the time to complete the trial by 4.93 ± 4.39% (43.20 ± 7.35 vs. 41.17 ± 6.18 min; p = 0.011; effect size [ES] = 0.300). Caffeine intake reduced the time to complete four out of eight sectors with different categories of technical difficulty (p ≤ 0.010; ES = 0.386 to 0.701). Mean heart rate was higher with caffeine (169 ± 6 vs. 162 ± 13 bpm; p = 0.046; ES = 0.788) but the rating of perceived exertion at the end of the trial was similar with caffeinated coffee than with the placebo (16 ± 1 vs. 16 ± 2 a.u.; p = 0.676; ES = 0.061). In conclusion, the intake of 3 mg/kg of caffeine delivered via soluble coffee reduced the time to complete a cross-country cycling trial in recreational cyclists. These results suggest that caffeine ingested as coffee may be an ergogenic substance for cross-country cycling.


Assuntos
Desempenho Atlético , Cafeína , Substâncias para Melhoria do Desempenho , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Desempenho Atlético/fisiologia , Cafeína/farmacologia , Café/química , Estudos Cross-Over
14.
Int J Mol Sci ; 25(5)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38473910

RESUMO

Caffeine is one of the most widely consumed psychoactive drugs in the world. It easily crosses the blood-brain barrier, and caffeine-interacting adenosine and ryanodine receptors are distributed in various areas of the brain, including the hypothalamus and pituitary. Caffeine intake may have an impact on reproductive and immune function. Therefore, in the present study performed on the ewe model, we decided to investigate the effect of peripheral administration of caffeine (30 mg/kg) on the secretory activity of the hypothalamic-pituitary unit which regulates the reproductive function in females during both a physiological state and an immune/inflammatory challenge induced by lipopolysaccharide (LPS; 400 ng/kg) injection. It was found that caffeine stimulated (p < 0.01) the biosynthesis of gonadotropin-releasing hormone (GnRH) in the hypothalamus of ewe under both physiological and inflammatory conditions. Caffeine also increased (p < 0.05) luteinizing hormone (LH) secretion in ewes in a physiological state; however, a single administration of caffeine failed to completely release the LH secretion from the inhibitory influence of inflammation. This could result from the decreased expression of GnRHR in the pituitary and it may also be associated with the changes in the concentration of neurotransmitters in the median eminence (ME) where GnRH neuron terminals are located. Caffeine and LPS increased (p < 0.05) dopamine in the ME which may explain the inhibition of GnRH release. Caffeine treatment also increased (p < 0.01) cortisol release, and this stimulatory effect was particularly evident in sheep under immunological stress. Our studies suggest that caffeine affects the secretory activity of the hypothalamic-pituitary unit, although its effect appears to be partially dependent on the animal's immune status.


Assuntos
Cafeína , Hormônio Liberador de Gonadotropina , Feminino , Ovinos , Animais , Hormônio Liberador de Gonadotropina/metabolismo , Cafeína/farmacologia , Hormônio Luteinizante/metabolismo , Lipopolissacarídeos/farmacologia , Hipotálamo/metabolismo
15.
Scand J Med Sci Sports ; 34(3): e14595, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38458991

RESUMO

We investigated the acute effects of caffeine supplementation (6 mgï½¥kg-1 ) on 60-m sprint performance and underlying components with a step-to-step ground reaction force measurement in 13 male sprinters. After the first round sprint as a control, caffeine supplementation-induced improvement in 60-m sprint times (7.811 s at the first versus 7.648 s at the second round, 2.05%) were greater compared with the placebo condition (7.769 s at the first versus 7.768 s at the second round, 0.02%). Using average values for every four steps, in the caffeine condition, higher running speed (all six step groups), higher step frequency (5th-16th and 21st-24th step groups), shorter support time (all the step groups except for 13th-16th step) and shorter braking time (9th-24th step groups) were found. Regarding ground reaction forces variables, greater braking mean force (13th-19th step group), propulsive mean force (1st-12th and 17th-20th step groups), and effective vertical mean force (9th-12th step group) were found in the caffeine condition. For the block clearance phase at the sprint start, push-off and reaction times did not change, while higher total anteroposterior mean force, average horizontal external power, and ratio of force were found in the caffeine condition. These results indicate that, compared with placebo, acute caffeine supplementation improved sprint performance regardless of sprint sections during the entire acceleration phase from the start through increases in step frequency with decreases in support time. Moreover, acute caffeine supplementation promoted increases in the propulsive mean force, resulting in the improvement of sprint performance.


Assuntos
Desempenho Atlético , Cafeína , Humanos , Masculino , Fenômenos Biomecânicos , Cafeína/farmacologia , Cinética , Aceleração , Suplementos Nutricionais
16.
PLoS One ; 19(3): e0298331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38530838

RESUMO

Electrochemical measurements, which exhibit high accuracy and sensitivity under low contamination, controlled electrolyte concentration, and pH conditions, have been used in determining various compounds. The electrochemical quantification capability decreases with an increase in the complexity of the measurement object. Therefore, solvent pretreatment and electrolyte addition are crucial in performing electrochemical measurements of specific compounds directly from beverages owing to the poor measurement quality caused by unspecified noise signals from foreign substances and unstable electrolyte concentrations. To prevent such signal disturbances from affecting quantitative analysis, spectral data of voltage-current values from electrochemical measurements must be used for principal component analysis (PCA). Moreover, this method enables highly accurate quantification even though numerical data alone are challenging to analyze. This study utilized boron-doped diamond (BDD) single-chip electrochemical detection to quantify caffeine content in commercial beverages without dilution. By applying PCA, we integrated electrochemical signals with known caffeine contents and subsequently utilized principal component regression to predict the caffeine content in unknown beverages. Consequently, we addressed existing research problems, such as the high quantification cost and the long measurement time required to obtain results after quantification. The average prediction accuracy was 93.8% compared to the actual content values. Electrochemical measurements are helpful in medical care and indirectly support our lives.


Assuntos
Cafeína , Café , Cafeína/análise , Boro/química , Eletrodos , Aprendizado de Máquina , Eletrólitos
17.
Neurology ; 102(8): e209201, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38513162

RESUMO

BACKGROUND AND OBJECTIVES: Inverse associations between caffeine intake and Parkinson disease (PD) have been frequently implicated in human studies. However, no studies have quantified biomarkers of caffeine intake years before PD onset and investigated whether and which caffeine metabolites are related to PD. METHODS: Associations between self-reported total coffee consumption and future PD risk were examined in the EPIC4PD study, a prospective population-based cohort including 6 European countries. Cases with PD were identified through medical records and reviewed by expert neurologists. Hazard ratios (HRs) and 95% CIs for coffee consumption and PD incidence were estimated using Cox proportional hazards models. A case-control study nested within the EPIC4PD was conducted, recruiting cases with incident PD and matching each case with a control by age, sex, study center, and fasting status at blood collection. Caffeine metabolites were quantified by high-resolution mass spectrometry in baseline collected plasma samples. Using conditional logistic regression models, odds ratios (ORs) and 95% CIs were estimated for caffeine metabolites and PD risk. RESULTS: In the EPIC4PD cohort (comprising 184,024 individuals), the multivariable-adjusted HR comparing the highest coffee intake with nonconsumers was 0.63 (95% CI 0.46-0.88, p = 0.006). In the nested case-control study, which included 351 cases with incident PD and 351 matched controls, prediagnostic caffeine and its primary metabolites, paraxanthine and theophylline, were inversely associated with PD risk. The ORs were 0.80 (95% CI 0.67-0.95, p = 0.009), 0.82 (95% CI 0.69-0.96, p = 0.015), and 0.78 (95% CI 0.65-0.93, p = 0.005), respectively. Adjusting for smoking and alcohol consumption did not substantially change these results. DISCUSSION: This study demonstrates that the neuroprotection of coffee on PD is attributed to caffeine and its metabolites by detailed quantification of plasma caffeine and its metabolites years before diagnosis.


Assuntos
Cafeína , Doença de Parkinson , Humanos , Cafeína/metabolismo , Café , Doença de Parkinson/diagnóstico , Doença de Parkinson/epidemiologia , Doença de Parkinson/etiologia , Estudos de Casos e Controles , Estudos Prospectivos , Fatores de Risco
18.
J Int Soc Sports Nutr ; 21(1): 2323919, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38466174

RESUMO

Caffeine is a popular ergogenic aid that has a plethora of evidence highlighting its positive effects. A Google Scholar search using the keywords "caffeine" and "exercise" yields over 200,000 results, emphasizing the extensive research on this topic. However, despite the vast amount of available data, it is intriguing that uncertainties persist regarding the effectiveness and safety of caffeine. These include but are not limited to: 1. Does caffeine dehydrate you at rest? 2. Does caffeine dehydrate you during exercise? 3. Does caffeine promote the loss of body fat? 4. Does habitual caffeine consumption influence the performance response to acute caffeine supplementation? 5. Does caffeine affect upper vs. lower body performance/strength differently? 6. Is there a relationship between caffeine and depression? 7. Can too much caffeine kill you? 8. Are there sex differences regarding caffeine's effects? 9. Does caffeine work for everyone? 10. Does caffeine cause heart problems? 11. Does caffeine promote the loss of bone mineral? 12. Should pregnant women avoid caffeine? 13. Is caffeine addictive? 14. Does waiting 1.5-2.0 hours after waking to consume caffeine help you avoid the afternoon "crash?" To answer these questions, we performed an evidence-based scientific evaluation of the literature regarding caffeine supplementation.


Assuntos
Cafeína , Substâncias para Melhoria do Desempenho , Masculino , Gravidez , Humanos , Feminino , Cafeína/farmacologia , Tecido Adiposo , Exercício Físico , Substâncias para Melhoria do Desempenho/farmacologia , Suplementos Nutricionais
19.
Int J Sports Physiol Perform ; 19(5): 427-434, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38335952

RESUMO

INTRODUCTION: The acute and isolated ingestion of sodium bicarbonate (NaHCO3) and caffeine (CAF) improves performance and delays fatigue in high-intensity tasks. However, it remains to be elucidated if the coingestion of both dietary supplements stimulates a summative ergogenic effect. This study aimed to examine the effect of the acute coingestion of NaHCO3 and CAF on repeated-sprint performance. METHODS: Twenty-five trained participants (age: 23.3 [4.0] y; sex [female/male]: 12/13; body mass: 69.6 [12.5] kg) participated in a randomized, double-blind, placebo (PLA) -controlled, crossover study. Participants were assigned to 4 conditions: (1) NaHCO3 + CAF, (2) NaHCO3, (3) CAF, or (4) PLA. Thus, they ingested 0.3 g/kg of NaHCO3, 3 mg/kg of CAF, or PLA. Then, participants performed 4 Wingate tests (Wt), consisting of a 30-second all-out sprint against an individualized resisted load, interspersed by a 1.5-minute rest period between sprints. RESULTS: Peak (Wpeak) and mean (Wmean) power output revealed a supplement and sprint interaction effect (P = .009 and P = .049, respectively). Compared with PLA, NaHCO3 + CAF and NaHCO3 increased Wpeak performance in Wt 3 (3%, P = .021) and Wt 4 (4.5%, P = .047), while NaHCO3 supplementation increased mean power performance in Wt 3 (4.2%, P = .001). In Wt 1, CAF increased Wpeak (3.2%, P = .054) and reduced time to Wpeak (-8.5%; P = .008). Plasma lactate showed a supplement plus sprint interaction (P < .001) when NaHCO3 was compared with CAF (13%, P = .031) and PLA (23%, P = .021). CONCLUSION: To summarize, although the isolated ingestion of CAF and NaHCO3 improved repeated-sprint performance, the coingestion of both supplements did not stimulate a synergic ergogenic effect.


Assuntos
Desempenho Atlético , Cafeína , Estudos Cross-Over , Suplementos Nutricionais , Ácido Láctico , Substâncias para Melhoria do Desempenho , Corrida , Bicarbonato de Sódio , Humanos , Bicarbonato de Sódio/administração & dosagem , Bicarbonato de Sódio/farmacologia , Cafeína/administração & dosagem , Masculino , Feminino , Desempenho Atlético/fisiologia , Método Duplo-Cego , Adulto Jovem , Substâncias para Melhoria do Desempenho/administração & dosagem , Corrida/fisiologia , Ácido Láctico/sangue , Adulto , Teste de Esforço
20.
J Clin Psychopharmacol ; 44(2): 161-167, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38421925

RESUMO

BACKGROUND: Some reports point to dietary caffeine intake as a cause of increased plasma clozapine concentrations in certain patients. METHODS: We compared clozapine dose and plasma clozapine and N-desmethylclozapine (norclozapine) concentrations in male and female smokers and nonsmokers in relation to reported (i) coffee (caffeine) and (ii) chocolate (caffeine and theobromine) intake in samples submitted for clozapine therapeutic drug monitoring, 1993-2017. RESULTS: There was information on coffee ingestion for 16,558 samples (8833 patients) from males and 5886 samples (3433 patients) from females and on chocolate ingestion for 12,616 samples (7568 patients) from males and 4677 samples (2939 patients) from females. When smoking was considered, there was no discernible effect of either coffee or chocolate ingestion either on the median dose of clozapine or on the median plasma clozapine and norclozapine concentrations in men and in women. However, cigarette smoking was associated with higher coffee and chocolate consumption. Although male nonsmokers who reported drinking 3 or more cups of coffee daily had significantly higher median plasma clozapine and norclozapine concentrations than those who drank less coffee, they were also prescribed a significantly higher clozapine dose. There was no clear effect of coffee ingestion on plasma clozapine and norclozapine in female nonsmokers. IMPLICATIONS: Inhibition of clozapine metabolism by caffeine at the doses of caffeine normally encountered in those treated with clozapine is unlikely even in male nonsmokers. Measurement of plasma caffeine in an appropriate sample should be considered in any future investigation into a presumed clozapine-caffeine interaction.


Assuntos
Chocolate , Clozapina/análogos & derivados , Feminino , Humanos , Masculino , Café , Cafeína
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