Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription...Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear.Here,we report a novel transcription factor Camellia sinensis Senescnece 40(CsS40)as a caffeine biosynthesis regulator,which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase(TCS1)promoter.Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays,a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter.Consistently,immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells.The expression pattern of CsS40 in‘Fuding Dabai’developing leaves was opposite to that of TCS1;and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels,respectively.The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of‘Fuding Dabai’.Furthermore,overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants,meanwhile,increased their susceptibility to aging.CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors.Taken together,we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar‘Fuding Dabai’.The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.展开更多
Tea plant(Camellia sinensis)is an important cash crop with extensive adaptability in the world.However,complex environmental factors force a large variation of tea quality-related components.Caffeine is essential for ...Tea plant(Camellia sinensis)is an important cash crop with extensive adaptability in the world.However,complex environmental factors force a large variation of tea quality-related components.Caffeine is essential for the formation of bitter and fresh flavors in tea,and is the main compound of tea that improves human alertness.Continuous strong light stimulation was observed to cause caffeine reduction in tea leaves,but the mechanism is not clear.In this study,the response of tea plant to light intensity was analysed mainly by multi-omics association,antisense oligodeoxynucleotide(asODN)silencing technique,and in vitro enzyme activity assay.The results revealed multiple strategies for light intensity adaptation in tea plant,among which the regulation of chloroplasts,photosynthesis,porphyrin metabolism,and resistance to oxidative stress were prominent.Caffeine catabolism was enhanced in continuous strong light,which may be a light-adapted strategy due to strict regulation by xanthine dehydrogenase(XDH).asODN silencing and enzymatic activity assays confirmed that CsXDH1 is a protein induced by light intensity to catalyze the substrate xanthine.CsXDH1 asODN silencing resulted in significant up-regulation of both caffeine and theobromine in in vitro enzyme activity assay,but not in vivo.CsXDH1 may act as a coordinator in light intensity adaptation,thus disrupting this balance of caffeine catabolism.展开更多
The current work imitates the trivial method which intricates the abstraction along with classification of caffeine accessible in variability of decoction shrubberies which are expended in two different states of Indi...The current work imitates the trivial method which intricates the abstraction along with classification of caffeine accessible in variability of decoction shrubberies which are expended in two different states of India (Telengana & Uttar Pradesh). As per observation individuals of both the states are identical tender of consumption of tea. Abstraction progression tangled variability of stages which are discoursed in the work. In addition, the outcome of drinking of caffeine or the permitted ingestion of caffeine over tea has also been conferred through the work and linked the data with the literature data. In this study, we used a UV-visible spectrophotometer as well as liquid-liquid extraction method to determine the caffeine content in various tea samples. The significance of this study lies in the fact that accurate determination of caffeine content is essential for quality control and labeling of tea products. The UV-visible spectrophotometer method was found to be simple, reliable, and sensitive for the detection of caffeine in tea samples.展开更多
Caffeine is an alkaloid present in a wide variety of plants. Currently the most consumed psychostimulant worldwide, its consumption is associated with several health benefits, including modulation of the innate and ad...Caffeine is an alkaloid present in a wide variety of plants. Currently the most consumed psychostimulant worldwide, its consumption is associated with several health benefits, including modulation of the innate and adaptive immune response, reduction of oxidative cellular stress, and decreased incidence of some cancers, including breast cancer. Breast cancer is the most common cause of cancer among women and the second leading cause of cancer death in women worldwide. The interaction between biomaterials and drugs has enabled a great advance in science for developing controlled drug delivery systems and has been used to treat numerous pathologies. This work aimed to evaluate the immunomodulatory effects of caffeine associated or not with polyethylene glycol adsorbed in microemulsion (MLP) on MCF-7 cells, phagocytic cells (MN), and coculture. For biological assays, ATCC (American Type Culture Collection, USA) cell lines of breast adenocarcinoma (MCF-7) and phagocytes (MN) obtained from voluntary donors were used. The cells (MN and MCF-7) and coculture were treated with caffeine and MLP and incubated for rheological characterization analyses: flow curve and viscosity, oxidative stress: superoxide anion assay (), and activity of the enzyme superoxide dismutase (Cu-Zn-SOD). Caffeine and MLP increased viscosity and blood and MCF-7 cells and affected the immunomodulation of oxidative stress metabolism of MN and MCF-7 cells treated with caffeine and associated caffeine to the MLP. These data suggest that caffeine is associated or not with MLP-induced immunomodulatory effects on MN phagocytes and MCF-7 cells, demonstrating the antitumor activity via oxidative stress and can be a complementary alternative for treating breast cancer.展开更多
Caffeine is one of the most commonly consumed stimulants and is found in many items like coffee and energy drinks. Heart arrhythmias are irregular heart rhythms, which can occur when the electrical signals that contro...Caffeine is one of the most commonly consumed stimulants and is found in many items like coffee and energy drinks. Heart arrhythmias are irregular heart rhythms, which can occur when the electrical signals that control the heart’s rhythm are not functioning properly. Due to the stimulant properties of caffeine, it is theorized that caffeine consumption may cause tachycardias-like ventricular arrhythmias. This review article describes the relationship between caffeine intake and heart arrhythmias using a comprehensive Pub-Med search. A comprehensive search was conducted using the search terms “caffeine arrhythmia” which was conducted and a total of 26 search results were obtained. The majority of clinical studies suggest that there are no strong associations between caffeine consumption and arrhythmias. There is little evidence suggesting a direct relationship between caffeine and ventricular arrhythmias (relative Risk 1.00, 95% CI 0.94 - 1.06;13.5%, p = 0.32). Conversely, caffeine consumption has an inverse relationship with the risk of atrial fibrillation (p for overall trend = 0.015;p for nonlinearity = 0.27). Caffeine related deaths are uncommon, but certain groups such as infants, psychiatric patients, and athletes may have an increased risk of arrhythmias following caffeine consumption. Overall, caffeine consumption is not strongly linked to heart arrhythmias and limited studies suggest it may reduce the risk of arrhythmias. Although there is not a strong relationship between caffeine intake and heart arrhythmias, it does cause other cardiovascular problems including high blood pressure and hence should be consumed responsibly (40 - 180 mg/day).展开更多
Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its c...Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.展开更多
For the production of a reference material from caffeine solution, one of the methods of characterization was HPLC-UV since caffeine is very sensitive to the UV. In this work, a batch solution of caffeine in water ref...For the production of a reference material from caffeine solution, one of the methods of characterization was HPLC-UV since caffeine is very sensitive to the UV. In this work, a batch solution of caffeine in water reference material of 1000 mg/kg has been gravimetrically prepared using a calibrated analytical balance. A sample of this solution was diluted to 25 mg/kg for measurement by HPLC-UV in the range 10 - 50 mg/kg. The chromatographic separation was carried out by C-18 column and a mobile phase assembled of 75% water and 25% methanol (v:v). The detection was made by the UV detector at 275 nm. The validation of this analytical method was carried out in accordance with requirements of the EURACHEM and ICH guidelines. The selectivity, linearity, accuracy, precision and trueness (recovery and bias) of the method were studied. The validation results proved that the method is fit-for-purpose of measuring the caffeine concentration in water in the range 10 - 50 mg/kg using HPLC-UV.展开更多
Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its c...Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.展开更多
AIM:To determine the molecular mechanisms involved in experimental hepatic fibrosis prevention by caffeine(CFA).METHODS:Liver fibrosis was induced in Wistar rats by intraperitoneal thioacetamide or bile duct ligation ...AIM:To determine the molecular mechanisms involved in experimental hepatic fibrosis prevention by caffeine(CFA).METHODS:Liver fibrosis was induced in Wistar rats by intraperitoneal thioacetamide or bile duct ligation and they were concomitantly treated with CFA(15 mg/kg per day).Fibrosis and inflammatory cell infiltrate were evaluated and classified by Knodell index.Inflammatory infiltrate was quantified by immunohistochemistry(anti-CD11b).Gene expression was analyzed by quantitative reverse transcription-polymerase chain reaction for collagenⅠ?(Col-1),connective tissue growth factor(CTGF),transforming growth factorβ1(TGF-β1),tumor necrosis factor alpha(TNF-α),interleukin-1(IL-1),IL-6,superoxide dismutase(SOD)and catalase(CAT).Activation of Nrf2 and Snail-1 was analyzed by Westernblot.TNF-αexpression was proved by enzyme-linked immunosorbant assay,CAT activity was performed by zymography.RESULTS:CFA treatment diminished fibrosis index in treated animals.The Knodell index showed both lower fibrosis and necroinflammation.Expression of profibrogenic genes CTGF,Col-1 and TGF-β1 and proinflammatory genes TNF-α,IL-6 and IL-1 was substantially diminished with CFA treatment with less CD11b positive areas.Significantly lower values of transcriptional factor Snail-1 were detected in CFA treated rats compared with cirrhotic rats without treatment;in contrast Nrf2was increased in the presence of CFA.Expression of SOD and CAT was greater in animals treated with CFA showing a strong correlation between mRNA expression and enzyme activity.CONCLUSION:Our results suggest that CFA inhibits the transcriptional factor Snail-1,down-regulating profibrogenic genes,and activates Nrf2 inducing antioxidant enzymes system,preventing inflammation and fibrosis.展开更多
Caffeine is the most commonly used medication for treatment of apnea of prematurity. Its effect has been well established in reducing the frequency of apnea, intermittent hypoxemia, and extubation failure in mechanica...Caffeine is the most commonly used medication for treatment of apnea of prematurity. Its effect has been well established in reducing the frequency of apnea, intermittent hypoxemia, and extubation failure in mechanically ventilated preterm infants. Evidence for additional short-term benefits on reducing the incidence of bronchopulmonary dysplasia and patent ductus arteriosus has also been suggested. Controversies existamong various neonatal intensive care units in terms of drug efficacy compared to other methylxanthines, dosage regimen, time of initiation, duration of therapy, drug safety and value of therapeutic drug monitoring. In the current review, we will summarize the available evidence for the best practice in using caffeine therapy in preterm infants.展开更多
Caffeine is present in products marketed for weight loss, with the purpose of increasing thermogenesis and lipid metabolism. The dosage declared by the product manufacturer, or even its presence, is not always correct...Caffeine is present in products marketed for weight loss, with the purpose of increasing thermogenesis and lipid metabolism. The dosage declared by the product manufacturer, or even its presence, is not always correctly described on the label. This work aimed to investigate the undeclared synthetic caffeine in weight loss formulations by a high-performance liquid chromatography with diode array detection(HPLC-DAD) method. From one hundred products purchased through Brazilian e-commerce, seventeen contained caffeine, either naturally or synthetically added to formulation. The caffeine-containing samples were confirmed by an ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method, and adulteration was clearly proven in five products. The content highest caffeine contained 448.8 mg per dose. Other irregularities were also found; nevertheless, the most serious was the addition of synthetic drugs without asking the consumers. Additional drugs expose the consumer to more possible side-effects as well as deleterious drug interactions. Intentional adulteration with any unlabeled substance is typically motivated by a desire to increase or alter the claimed effect of the marketed product to gain a commercial advantage.展开更多
Catechins in green tea have various useful features including antioxidant activity and preventive effects on metabolic syndrome. Various beverages that are enriched with tea catechins are marketed as Foods for Specifi...Catechins in green tea have various useful features including antioxidant activity and preventive effects on metabolic syndrome. Various beverages that are enriched with tea catechins are marketed as Foods for Specified Health Uses (FOSHU) in Japan. However, recent reports have indicated that excessive consumption of green tea extracts as a dietary supplement are associated with adverse health effects such as liver disorders. Various catechins and caffeine are constituents of FOSHU tea-based beverages. The amount of catechins in FOSHU products is displayed on labels as total catechin content, but the content of individual catechins are not provided. Although health hazards of FOSHU products have rarely been reported, precise information about the content and types of catechins in FOSHU products is needed to ensure safety. We used high-performance liquid chromatography with a photodiode array (HPLC/PDA) to simultaneously identify and quantify catechins and caffeine in green tea-based popular beverages and FOSHU beverages. This technique allowed simultaneous quantitation of five types of catechins and caffeine in green tea without complicated sample preparation. Epigallocatechin gallate (EGCG) and epigallocatechin EGC were the main catechins in various FOSHU beverages and the concentrations of almost all catechins were higher in FOSHU, than in popular green tea-based beverages. The concentrations of EGCG in green tea-based popular beverages and in FOSHU beverages were 5.4 - 7.3 and 10.2 - 41.9 mg/100mL, respectively, with the highest concentration being in a product named Healthya (approximately 147 mg/bottle). The simultaneous determination of compounds such as catechins and caffeine in FOSHU beverages can help to estimate beneficial and adverse effects to prevent deleterious effects on health and the excessive consumption of FOSHU beverages containing high concentrations of tea catechins should be avoided.展开更多
BACKGROUND:Caffeinated energy drinks are widely used worldwide.They are associated with a variety of adverse effects and are of concern to health authorities,yet there is still scarce information about their adverse e...BACKGROUND:Caffeinated energy drinks are widely used worldwide.They are associated with a variety of adverse effects and are of concern to health authorities,yet there is still scarce information about their adverse effects and inadequate awareness among medical personnel.METHODS:Case description and discussion of a patient presenting to the emergency room after overdose of energy drinks in combination with 3,4-methylenedioxymethamphetamine(MDMA).RESULTS:Despite best medical efforts,the patient died of fatal cardiac arrhythmias.There is a paucity of information about adverse effects of energy drinks.CONCLUSION:Although energy drinks are widely used,there is a lack of awareness in the population and medical staff about their hazards.展开更多
The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrop...The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrophysiological tip recording. Behavioral experiments showed that caffeine was a feeding deterrent for both larvae, but it showed a stronger feeding deterring effect on the oligophagous H. assulta . The electrophysiological tip-recording results showed that both H. armigera larvae and H. assulta larvae had one caffeine-sensitive feeding deterrent neuron at the medial sensilla, and the electrophysiological pulse response of H. assulta larvae was significantly stronger than that of H. armigera larvae. Therefore, caffeine had a stronger feeding deterring effect on the oligophagous H. assulta than the polyphagous H. armigera . The difference in behavioral effect was closely related to the sensitivity of to caffeine the feeding deterrent neurons at the medial sensilla.展开更多
The present letter to editor is related to“Cui WQ,Wang ST,Pan D,Chang B,Sang LX.Caffeine and its main targets of colorectal cancer.World J Gastrointest Oncol 2020;12(2):149-172[DOI:10.4251/wjgo.v12.i2.149]”.
To find possible therapeutic applications involving the Central Nervous System (CNS) for herbals is a major challenge during functional food and drug discovery and development programmes. Despite the availability of n...To find possible therapeutic applications involving the Central Nervous System (CNS) for herbals is a major challenge during functional food and drug discovery and development programmes. Despite the availability of numerous in vitro and in vivo tests, there is no single agreed screening procedure for pharmacological testing of herbal extracts with anticipated CNS activity. Experience gained from more than 25 years of testing has shown that two models give reasonably reliable orientation for future CNS applications: construction of an electropharmacogram based on wireless recording of field potentials from the depth of the brain of freely moving rats (Tele-Stereo-EEG) and recording of the population spike produced by pyramidal cells from hippocampal slices in vitro. A combination of these two methods has now been used to characterize the pharmacological profile of extracts from Rhodiola rosea root, Oenothera paradoxa seeds and Paullinia cupana seeds. Spectral analysis of field potentials revealed attenuation of alpha2 and beta1 waves was common for all extracts. According to previous studies, this is interpreted as activation of the dopaminergic and glutamatergic transmission. In addition, Oenothera and Rhodiola extracts attenuated delta and theta power, probably related to interference with the cholinergic and norepinephrinergic transmission, respectively. Using discriminant analysis for comparison with reference pharmaceutical and botanical drugs, Rhodiola projected near the position of Ginkgo extract, whereas Oenothera extract was projected near the position of Tramadol, an analgesic drug. Physical motion was increased only in the presence of Paullinia extract and caffeine. Increases of long-term potentiation were observed in the presence of Rhodiola extract, Paullinia extract and caffeine. The combined information predicts stimulant and cognitive function-enhancing activities in humans for the Rhodiola extract, which could also be used as a possible caffeine-replacement, and antidepressant and analgesic activity for the Oenothera extract.展开更多
Parkinson's disease (PD) is disorder affecting more than a common neurodegenerative 1% people above 60 years of age worldwide, manifesting as the impaired motor function such as tremors, rigidity, akinesia/bradykin...Parkinson's disease (PD) is disorder affecting more than a common neurodegenerative 1% people above 60 years of age worldwide, manifesting as the impaired motor function such as tremors, rigidity, akinesia/bradykinesia and postural inefficiency with a reduced life expectancy (Dorsey et al., 2007). PD is believed to be the end result of the progressive death of dopaminergic neurons in the substantia nigra pars compacta (SNc).展开更多
基金supported by the National Natural Science Foundation of China(3226180451,3226180488)Guizhou Province Outstanding Young Scientific and Technological Talent Cultivation Project(Qiankehe PlatformTalent[2019]5651)Guizhou Province Science and Technology Planning Project(Qiankehe Support[2021]General 111).
文摘Caffeine is considered as one of the most important bioactive components in the popular plant beverages tea,cacao,and coffee,but as a wide-spread plant secondary metabolite its biosynthetic regulation at transcription level remains largely unclear.Here,we report a novel transcription factor Camellia sinensis Senescnece 40(CsS40)as a caffeine biosynthesis regulator,which was discovered during screening a yeast expression library constructed from tea leaf cDNAs for activation of tea caffeine synthase(TCS1)promoter.Besides multiple hits of the non-self-activation CsS40 clones that bound to and activated TCS1 promoter in yeast-one-hybrid assays,a split-luciferase complementation assay demonstrated that CsS40 acts as a transcription factor to activate the CsTCS1 gene and EMSA assay also demonstrated that CsS40 bound to the TCS1 gene promoter.Consistently,immunofluorescence data indicated that CsS40-GFP fusion was localized in the nuclei of tobacco epidermal cells.The expression pattern of CsS40 in‘Fuding Dabai’developing leaves was opposite to that of TCS1;and knockdown and overexpression of CsS40 in tea leaf calli significantly increased and decreased TCS1 expression levels,respectively.The expression levels of CsS40 were also negatively correlated to caffeine accumulation in developing leaves and transgenic calli of‘Fuding Dabai’.Furthermore,overexpression of CsS40 reduced the accumulation of xanthine and hypoxanthine in tobacco plants,meanwhile,increased their susceptibility to aging.CsS40 expression in tea leaves was also induced by senescence-promoting hormones and environmental factors.Taken together,we showed that a novel senescence-related factor CsS40 negatively regulates TCS1 and represses caffeine accumulation in tea cultivar‘Fuding Dabai’.The study provides new insights into caffeine biosynthesis regulation by a plant-specific senescence regulator in tea plants in connection to leaf senescence and hormone signaling.
基金This work was supported by the Chongqing Technology Innovation and Application Demonstration Project(cstc2021jscxgksbX0016)the Germplasm Creation Research Program of Southwest University.
文摘Tea plant(Camellia sinensis)is an important cash crop with extensive adaptability in the world.However,complex environmental factors force a large variation of tea quality-related components.Caffeine is essential for the formation of bitter and fresh flavors in tea,and is the main compound of tea that improves human alertness.Continuous strong light stimulation was observed to cause caffeine reduction in tea leaves,but the mechanism is not clear.In this study,the response of tea plant to light intensity was analysed mainly by multi-omics association,antisense oligodeoxynucleotide(asODN)silencing technique,and in vitro enzyme activity assay.The results revealed multiple strategies for light intensity adaptation in tea plant,among which the regulation of chloroplasts,photosynthesis,porphyrin metabolism,and resistance to oxidative stress were prominent.Caffeine catabolism was enhanced in continuous strong light,which may be a light-adapted strategy due to strict regulation by xanthine dehydrogenase(XDH).asODN silencing and enzymatic activity assays confirmed that CsXDH1 is a protein induced by light intensity to catalyze the substrate xanthine.CsXDH1 asODN silencing resulted in significant up-regulation of both caffeine and theobromine in in vitro enzyme activity assay,but not in vivo.CsXDH1 may act as a coordinator in light intensity adaptation,thus disrupting this balance of caffeine catabolism.
文摘The current work imitates the trivial method which intricates the abstraction along with classification of caffeine accessible in variability of decoction shrubberies which are expended in two different states of India (Telengana & Uttar Pradesh). As per observation individuals of both the states are identical tender of consumption of tea. Abstraction progression tangled variability of stages which are discoursed in the work. In addition, the outcome of drinking of caffeine or the permitted ingestion of caffeine over tea has also been conferred through the work and linked the data with the literature data. In this study, we used a UV-visible spectrophotometer as well as liquid-liquid extraction method to determine the caffeine content in various tea samples. The significance of this study lies in the fact that accurate determination of caffeine content is essential for quality control and labeling of tea products. The UV-visible spectrophotometer method was found to be simple, reliable, and sensitive for the detection of caffeine in tea samples.
文摘Caffeine is an alkaloid present in a wide variety of plants. Currently the most consumed psychostimulant worldwide, its consumption is associated with several health benefits, including modulation of the innate and adaptive immune response, reduction of oxidative cellular stress, and decreased incidence of some cancers, including breast cancer. Breast cancer is the most common cause of cancer among women and the second leading cause of cancer death in women worldwide. The interaction between biomaterials and drugs has enabled a great advance in science for developing controlled drug delivery systems and has been used to treat numerous pathologies. This work aimed to evaluate the immunomodulatory effects of caffeine associated or not with polyethylene glycol adsorbed in microemulsion (MLP) on MCF-7 cells, phagocytic cells (MN), and coculture. For biological assays, ATCC (American Type Culture Collection, USA) cell lines of breast adenocarcinoma (MCF-7) and phagocytes (MN) obtained from voluntary donors were used. The cells (MN and MCF-7) and coculture were treated with caffeine and MLP and incubated for rheological characterization analyses: flow curve and viscosity, oxidative stress: superoxide anion assay (), and activity of the enzyme superoxide dismutase (Cu-Zn-SOD). Caffeine and MLP increased viscosity and blood and MCF-7 cells and affected the immunomodulation of oxidative stress metabolism of MN and MCF-7 cells treated with caffeine and associated caffeine to the MLP. These data suggest that caffeine is associated or not with MLP-induced immunomodulatory effects on MN phagocytes and MCF-7 cells, demonstrating the antitumor activity via oxidative stress and can be a complementary alternative for treating breast cancer.
文摘Caffeine is one of the most commonly consumed stimulants and is found in many items like coffee and energy drinks. Heart arrhythmias are irregular heart rhythms, which can occur when the electrical signals that control the heart’s rhythm are not functioning properly. Due to the stimulant properties of caffeine, it is theorized that caffeine consumption may cause tachycardias-like ventricular arrhythmias. This review article describes the relationship between caffeine intake and heart arrhythmias using a comprehensive Pub-Med search. A comprehensive search was conducted using the search terms “caffeine arrhythmia” which was conducted and a total of 26 search results were obtained. The majority of clinical studies suggest that there are no strong associations between caffeine consumption and arrhythmias. There is little evidence suggesting a direct relationship between caffeine and ventricular arrhythmias (relative Risk 1.00, 95% CI 0.94 - 1.06;13.5%, p = 0.32). Conversely, caffeine consumption has an inverse relationship with the risk of atrial fibrillation (p for overall trend = 0.015;p for nonlinearity = 0.27). Caffeine related deaths are uncommon, but certain groups such as infants, psychiatric patients, and athletes may have an increased risk of arrhythmias following caffeine consumption. Overall, caffeine consumption is not strongly linked to heart arrhythmias and limited studies suggest it may reduce the risk of arrhythmias. Although there is not a strong relationship between caffeine intake and heart arrhythmias, it does cause other cardiovascular problems including high blood pressure and hence should be consumed responsibly (40 - 180 mg/day).
文摘Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.
文摘For the production of a reference material from caffeine solution, one of the methods of characterization was HPLC-UV since caffeine is very sensitive to the UV. In this work, a batch solution of caffeine in water reference material of 1000 mg/kg has been gravimetrically prepared using a calibrated analytical balance. A sample of this solution was diluted to 25 mg/kg for measurement by HPLC-UV in the range 10 - 50 mg/kg. The chromatographic separation was carried out by C-18 column and a mobile phase assembled of 75% water and 25% methanol (v:v). The detection was made by the UV detector at 275 nm. The validation of this analytical method was carried out in accordance with requirements of the EURACHEM and ICH guidelines. The selectivity, linearity, accuracy, precision and trueness (recovery and bias) of the method were studied. The validation results proved that the method is fit-for-purpose of measuring the caffeine concentration in water in the range 10 - 50 mg/kg using HPLC-UV.
文摘Caffeine intake by pregnant women, adults and children can be harmful to the health of all particularly fetuses if the intake exceeds the permissible limits. Therefore, it is of fundamental importance to measure its concentration accurately using certified reference materials (CRMs). In the literature, no scientific details are published about the certification of caffeine standard solutions, and therefore, the present article covers this gap. A batch of caffeine solution was prepared in concentration of 1000 mg/kg and bottled. Homogeneity and stability of the candidate reference material were assessed by HPLC-UV and the results showed that the material is homogenous and stable enough. Characterization of the caffeine reference material was performed by HPLC-UV, LC-MS/MS and UV-VIS-NIR spectrophotometer in three different days and the characterization uncertainty was estimated in accordance with the requirements of ISO GUM. The certified value (999.86 ± 8.57 mg/kg) was derived as a weighted mean from the gravimetry and the three characterization methods and the certified uncertainty was calculated according to ISO Guide 35. The produced CRM is of strong interest to the food and drug analytical laboratories for the validity and credibility of their caffeine measurement results.
基金Supported by Conacyt grant No.25474 to Juan ArmendárizBorunda
文摘AIM:To determine the molecular mechanisms involved in experimental hepatic fibrosis prevention by caffeine(CFA).METHODS:Liver fibrosis was induced in Wistar rats by intraperitoneal thioacetamide or bile duct ligation and they were concomitantly treated with CFA(15 mg/kg per day).Fibrosis and inflammatory cell infiltrate were evaluated and classified by Knodell index.Inflammatory infiltrate was quantified by immunohistochemistry(anti-CD11b).Gene expression was analyzed by quantitative reverse transcription-polymerase chain reaction for collagenⅠ?(Col-1),connective tissue growth factor(CTGF),transforming growth factorβ1(TGF-β1),tumor necrosis factor alpha(TNF-α),interleukin-1(IL-1),IL-6,superoxide dismutase(SOD)and catalase(CAT).Activation of Nrf2 and Snail-1 was analyzed by Westernblot.TNF-αexpression was proved by enzyme-linked immunosorbant assay,CAT activity was performed by zymography.RESULTS:CFA treatment diminished fibrosis index in treated animals.The Knodell index showed both lower fibrosis and necroinflammation.Expression of profibrogenic genes CTGF,Col-1 and TGF-β1 and proinflammatory genes TNF-α,IL-6 and IL-1 was substantially diminished with CFA treatment with less CD11b positive areas.Significantly lower values of transcriptional factor Snail-1 were detected in CFA treated rats compared with cirrhotic rats without treatment;in contrast Nrf2was increased in the presence of CFA.Expression of SOD and CAT was greater in animals treated with CFA showing a strong correlation between mRNA expression and enzyme activity.CONCLUSION:Our results suggest that CFA inhibits the transcriptional factor Snail-1,down-regulating profibrogenic genes,and activates Nrf2 inducing antioxidant enzymes system,preventing inflammation and fibrosis.
文摘Caffeine is the most commonly used medication for treatment of apnea of prematurity. Its effect has been well established in reducing the frequency of apnea, intermittent hypoxemia, and extubation failure in mechanically ventilated preterm infants. Evidence for additional short-term benefits on reducing the incidence of bronchopulmonary dysplasia and patent ductus arteriosus has also been suggested. Controversies existamong various neonatal intensive care units in terms of drug efficacy compared to other methylxanthines, dosage regimen, time of initiation, duration of therapy, drug safety and value of therapeutic drug monitoring. In the current review, we will summarize the available evidence for the best practice in using caffeine therapy in preterm infants.
文摘Caffeine is present in products marketed for weight loss, with the purpose of increasing thermogenesis and lipid metabolism. The dosage declared by the product manufacturer, or even its presence, is not always correctly described on the label. This work aimed to investigate the undeclared synthetic caffeine in weight loss formulations by a high-performance liquid chromatography with diode array detection(HPLC-DAD) method. From one hundred products purchased through Brazilian e-commerce, seventeen contained caffeine, either naturally or synthetically added to formulation. The caffeine-containing samples were confirmed by an ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS) method, and adulteration was clearly proven in five products. The content highest caffeine contained 448.8 mg per dose. Other irregularities were also found; nevertheless, the most serious was the addition of synthetic drugs without asking the consumers. Additional drugs expose the consumer to more possible side-effects as well as deleterious drug interactions. Intentional adulteration with any unlabeled substance is typically motivated by a desire to increase or alter the claimed effect of the marketed product to gain a commercial advantage.
文摘Catechins in green tea have various useful features including antioxidant activity and preventive effects on metabolic syndrome. Various beverages that are enriched with tea catechins are marketed as Foods for Specified Health Uses (FOSHU) in Japan. However, recent reports have indicated that excessive consumption of green tea extracts as a dietary supplement are associated with adverse health effects such as liver disorders. Various catechins and caffeine are constituents of FOSHU tea-based beverages. The amount of catechins in FOSHU products is displayed on labels as total catechin content, but the content of individual catechins are not provided. Although health hazards of FOSHU products have rarely been reported, precise information about the content and types of catechins in FOSHU products is needed to ensure safety. We used high-performance liquid chromatography with a photodiode array (HPLC/PDA) to simultaneously identify and quantify catechins and caffeine in green tea-based popular beverages and FOSHU beverages. This technique allowed simultaneous quantitation of five types of catechins and caffeine in green tea without complicated sample preparation. Epigallocatechin gallate (EGCG) and epigallocatechin EGC were the main catechins in various FOSHU beverages and the concentrations of almost all catechins were higher in FOSHU, than in popular green tea-based beverages. The concentrations of EGCG in green tea-based popular beverages and in FOSHU beverages were 5.4 - 7.3 and 10.2 - 41.9 mg/100mL, respectively, with the highest concentration being in a product named Healthya (approximately 147 mg/bottle). The simultaneous determination of compounds such as catechins and caffeine in FOSHU beverages can help to estimate beneficial and adverse effects to prevent deleterious effects on health and the excessive consumption of FOSHU beverages containing high concentrations of tea catechins should be avoided.
文摘BACKGROUND:Caffeinated energy drinks are widely used worldwide.They are associated with a variety of adverse effects and are of concern to health authorities,yet there is still scarce information about their adverse effects and inadequate awareness among medical personnel.METHODS:Case description and discussion of a patient presenting to the emergency room after overdose of energy drinks in combination with 3,4-methylenedioxymethamphetamine(MDMA).RESULTS:Despite best medical efforts,the patient died of fatal cardiac arrhythmias.There is a paucity of information about adverse effects of energy drinks.CONCLUSION:Although energy drinks are widely used,there is a lack of awareness in the population and medical staff about their hazards.
基金Supported by the National Natural Science Foundation of China(31201750)Hunan Provincial Natural Science Foundation of China(2016JJ4009)
文摘The dual-choices tests of behavioral test were used to study the gustatory behavioral responses to caffeine of Helicoverpa armigera larvae and H. assulta larvae. Electrophysiological responses were studied by electrophysiological tip recording. Behavioral experiments showed that caffeine was a feeding deterrent for both larvae, but it showed a stronger feeding deterring effect on the oligophagous H. assulta . The electrophysiological tip-recording results showed that both H. armigera larvae and H. assulta larvae had one caffeine-sensitive feeding deterrent neuron at the medial sensilla, and the electrophysiological pulse response of H. assulta larvae was significantly stronger than that of H. armigera larvae. Therefore, caffeine had a stronger feeding deterring effect on the oligophagous H. assulta than the polyphagous H. armigera . The difference in behavioral effect was closely related to the sensitivity of to caffeine the feeding deterrent neurons at the medial sensilla.
文摘The present letter to editor is related to“Cui WQ,Wang ST,Pan D,Chang B,Sang LX.Caffeine and its main targets of colorectal cancer.World J Gastrointest Oncol 2020;12(2):149-172[DOI:10.4251/wjgo.v12.i2.149]”.
文摘To find possible therapeutic applications involving the Central Nervous System (CNS) for herbals is a major challenge during functional food and drug discovery and development programmes. Despite the availability of numerous in vitro and in vivo tests, there is no single agreed screening procedure for pharmacological testing of herbal extracts with anticipated CNS activity. Experience gained from more than 25 years of testing has shown that two models give reasonably reliable orientation for future CNS applications: construction of an electropharmacogram based on wireless recording of field potentials from the depth of the brain of freely moving rats (Tele-Stereo-EEG) and recording of the population spike produced by pyramidal cells from hippocampal slices in vitro. A combination of these two methods has now been used to characterize the pharmacological profile of extracts from Rhodiola rosea root, Oenothera paradoxa seeds and Paullinia cupana seeds. Spectral analysis of field potentials revealed attenuation of alpha2 and beta1 waves was common for all extracts. According to previous studies, this is interpreted as activation of the dopaminergic and glutamatergic transmission. In addition, Oenothera and Rhodiola extracts attenuated delta and theta power, probably related to interference with the cholinergic and norepinephrinergic transmission, respectively. Using discriminant analysis for comparison with reference pharmaceutical and botanical drugs, Rhodiola projected near the position of Ginkgo extract, whereas Oenothera extract was projected near the position of Tramadol, an analgesic drug. Physical motion was increased only in the presence of Paullinia extract and caffeine. Increases of long-term potentiation were observed in the presence of Rhodiola extract, Paullinia extract and caffeine. The combined information predicts stimulant and cognitive function-enhancing activities in humans for the Rhodiola extract, which could also be used as a possible caffeine-replacement, and antidepressant and analgesic activity for the Oenothera extract.
基金supported by funding from CSIR network project(BSC0115)
文摘Parkinson's disease (PD) is disorder affecting more than a common neurodegenerative 1% people above 60 years of age worldwide, manifesting as the impaired motor function such as tremors, rigidity, akinesia/bradykinesia and postural inefficiency with a reduced life expectancy (Dorsey et al., 2007). PD is believed to be the end result of the progressive death of dopaminergic neurons in the substantia nigra pars compacta (SNc).