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https://www.readbyqxmd.com/read/27635133/a-90-day-oral-toxicological-evaluation-of-the-methylurate-purine-alkaloid-theacrine
#1
Amy Clewell, Gábor Hirka, Róbert Glávits, Philip A Palmer, John R Endres, Timothy S Murbach, Tennille Marx, Ilona Pasics Szakonyiné
A 90-day repeated-dose oral toxicological evaluation was conducted according to GLP and OECD guidelines on the methylurate purine alkaloid theacrine, which is found naturally in certain plants. Four groups of Hsd.Brl.Han Wistar rats (ten/sex/group) were administered theacrine by gavage doses of 0 (vehicle only), 180, 300, and 375 mg/kg bw/day. Two females and one male in the 300 and 375 mg/kg bw/day groups, respectively, died during the study. Histological examination revealed centrilobular hepatocellular necrosis as the probable cause of death...
2016: Journal of Toxicology
https://www.readbyqxmd.com/read/27596421/a-comparative-analysis-of-chemical-compositions-in-camellia-sinensis-var-puanensis-kurihara-a-novel-chinese-tea-by-hplc-and-uflc-q-tof-ms-ms
#2
Yi-Fang Li, Shu-Hua Ouyang, Yi-Qun Chang, Ting-Mei Wang, Wei-Xi Li, Hai-Yan Tian, Hong Cao, Hiroshi Kurihara, Rong-Rong He
Camellia sinensis var. puanensis Kurihara (Puan tea) is a kind of ancient tea plant newly found in Jiangxipo and the surrounding areas of Puan County (Guizhou, China). People there always believe that drinking Puan tea is beneficial to the promotion of health and prevention of diseases. However, detailed information on its compositions has not been reported. Therefore, in this study, the varieties and contents of purine alkaloids and polyphenols in Puan tea were identified and determined by HPLC and UFLC-Q-TOF-MS/MS...
February 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27164220/a-two-part-approach-to-examine-the-effects-of-theacrine-teacrine%C3%A2-supplementation-on-oxygen-consumption-hemodynamic-responses-and-subjective-measures-of-cognitive-and-psychometric-parameters
#3
Tim N Ziegenfuss, Scott M Habowski, Jennifer E Sandrock, A William Kedia, Chad M Kerksick, Hector L Lopez
Theacrine (1,3,7,9-tetramethyluric acid) is a naturally occurring purine alkaloid, present in Camellia assamica variety kucha tea. Using a two-part approach in humans, the impact of theacrine (TeaCrine®, TC) was used to examine subjective dose-response, daily changes in cognitive and psychometric parameters, and changes in gas exchange and vital signs. All indicators were chosen to better ascertain the previously reported animal and human outcomes involving theacrine administration. Part 1 was a randomized, open-label, dose-response investigation in nine healthy participants whereby three participants ingested 400 mg TC per day and six participants ingested 200 mg/day...
May 10, 2016: Journal of Dietary Supplements
https://www.readbyqxmd.com/read/26766930/safety-of-teacrine%C3%A2-a-non-habituating-naturally-occurring-purine-alkaloid-over-eight-weeks-of-continuous-use
#4
RANDOMIZED CONTROLLED TRIAL
Lem Taylor, Petey Mumford, Mike Roberts, Sara Hayward, Jacy Mullins, Stacie Urbina, Colin Wilborn
BACKGROUND: Theacrine (1,3,7,9-tetramethyluric acid) is a purine alkaloid found in certain coffee (Coffea) species, fruits (Cupuacu [Theobroma grandiflorum]), and tea (Camellia assamica, var. kucha) that has anti-inflammatory, analgesic, and neuro-locomotor properties. Recent preliminary research has also reported increased feelings of energy, reduced fatigue, and strong effects on improving focus, concentration, and motivation to exercise. The purpose of this study was to examine the safety and non-habituating effects of TeaCrine®, a nature-identical, chemically equivalent bioactive version of theacrine...
2016: Journal of the International Society of Sports Nutrition
https://www.readbyqxmd.com/read/26610558/cognitive-performance-and-mood-following-ingestion-of-a-theacrine-containing-dietary-supplement-caffeine-or-placebo-by-young-men-and-women
#5
RANDOMIZED CONTROLLED TRIAL
Daniel J Kuhman, Keanan J Joyner, Richard J Bloomer
Theacrine is a purine alkaloid found primarily in the leaves of the Camellia Kucha plant and is now included within dietary supplements. To compare the effects of a theacrine-containing dietary supplement with caffeine and placebo on energy and mood, as well as objective measures of cognitive performance, heart rate, and blood pressure, 10 healthy men (20.8 ± 0.7 years) and 10 healthy women (22.2 ± 1.1 years) ingested the dietary supplement TheaTrim (Purus Labs; containing a branded form of theacrine (Teacrine™) and caffeine (150 mg)), caffeine only (150 mg), or a placebo on three different days, separated by approximately one week...
November 2015: Nutrients
https://www.readbyqxmd.com/read/25624250/comparing-antioxidant-capacity-of-purine-alkaloids-a-new-efficient-trio-for-screening-and-discovering-potential-antioxidants-in-vitro-and-in-vivo
#6
Bun Tsoi, Ruo-Nan Yi, Ling-Fang Cao, Shan-Bing Li, Rui-Rong Tan, Min Chen, Xiao-Xiao Li, Chen Wang, Yi-Fang Li, Hiroshi Kurihara, Rong-Rong He
The most commonly applied strategies for the evaluation of antioxidant capacity are the chemical- or cell-based approaches. However, the results obtained from these methods might not reflect the antioxidant ability of test samples within organisms. In this study, we propose a combination of experiments, including oxygen radical absorbance capacity (ORAC), cellular antioxidant activity assay (CAA), and the chick embryo model, as an efficient trio to evaluate antioxidant capacity of food components. Taking purine alkaloids as example, results demonstrate that chemical and cellular method might misinterpret their true ability on antioxidation...
June 1, 2015: Food Chemistry
https://www.readbyqxmd.com/read/25043720/differing-chemical-compositions-of-three-teas-may-explain-their-different-effects-on-acute-blood-pressure-in-spontaneously-hypertensive-rats
#7
Shan-Bing Li, Yi-Fang Li, Zhong-Fu Mao, Hui-Hua Hu, Shu-Hua Ouyang, Yan-Ping Wu, Bun Tsoi, Pin Gong, Hiroshi Kurihara, Rong-Rong He
BACKGROUND: Heavy tea consumption is suggested to be unsuitable for hypertensive people. However, the bioactive substances in different varieties of tea leaves are very different. This study compares the effects of three Chinese teas - C. sinensis, C. ptilophylla and C. assamica var. kucha - on blood pressure (BP) and heart rate in spontaneously hypertensive rats (SHRs). RESULTS: Intragastric administration of C. sinensis extract led to an acute increase in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate in SHRs...
April 2015: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/23724689/-determination-of-theacrine-in-rat-plasma-by-rp-hplc
#8
Wei-Ku Zhang, Jie-Kun Xu, Jie-Qing Hu, Su-Bo Wang, Ping Li, Kurihara Hiroshi, Xin-Sheng Yao, Bing-Hua Tang
OBJECTIVE: To establish a method for the determination of theacrine in rat plasma after ig. administration of theacrine. METHOD: Blood sample was taken timely from the eyes canthus of rats. Plasma was isolated and the protein was precipitated by ethyl acetate. Then the plasma concentration of theacrine was determined with RP-HPLC. Caffeine was used as the internal standard. The chromatographic conditions were as follows: Phenomenex Luna C18 (4.6 mm x 250 mm, 5 microm) at 25 degrees C, a mixture of methanol-water (25: 75) as the mobile phase, at the flow rate of 1...
March 2013: Zhongguo Zhong Yao za Zhi, Zhongguo Zhongyao Zazhi, China Journal of Chinese Materia Medica
https://www.readbyqxmd.com/read/23678853/theacrine-a-purine-alkaloid-obtained-from-camellia-assamica-var-kucha-attenuates-restraint-stress-provoked-liver-damage-in-mice
#9
Wei-Xi Li, Yi-Fang Li, Yu-Jia Zhai, Wei-Min Chen, Hiroshi Kurihara, Rong-Rong He
Theacrine (1,3,7,9-tetramethyluric acid), a purine alkaloid, has proven to be beneficial in maintaining several brain functions and is being studied for potential medicinal uses in recent years. In this study, we isolated theacrine from Camellia assamica var. kucha and investigated its protective effects on liver damage induced by restraint stress in mice. Results showed that 18 h of restraint stress could induce liver damage, with an obvious increase in levels of plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST)...
July 3, 2013: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/22579816/locomotor-activation-by-theacrine-a-purine-alkaloid-structurally-similar-to-caffeine-involvement-of-adenosine-and-dopamine-receptors
#10
Allison A Feduccia, Yuanyuan Wang, Jeffrey A Simms, Henry Y Yi, Rui Li, Leonard Bjeldanes, Chuangxing Ye, Selena E Bartlett
Purine compounds, such as caffeine, have many health-promoting properties and have proven to be beneficial in treating a number of different conditions. Theacrine, a purine alkaloid structurally similar to caffeine and abundantly present in Camellia kucha, has recently become of interest as a potential therapeutic compound. In the present study, theacrine was tested using a rodent behavioral model to investigate the effects of the drug on locomotor activity. Long Evans rats were injected with theacrine (24 or 48 mg/kg, i...
August 2012: Pharmacology, Biochemistry, and Behavior
https://www.readbyqxmd.com/read/20227468/theacrine-a-purine-alkaloid-with-anti-inflammatory-and-analgesic-activities
#11
Yuanyuan Wang, Xiaorong Yang, Xinqiang Zheng, Jing Li, Chuangxing Ye, Xiaohong Song
The anti-inflammatory and analgesic effects of theacrine (1, 3, 7, 9-tetramethyluric acid), a purine alkaloid which is abundantly present in Camellia kucha, were investigated. Xylene-induced ear edema, acetic acid-induced vascular permeability and lambda-carrageenan-induced paw edema were used to investigate anti-inflammatory activity, and acetic acid-induced writhing and hot-plate tests were used to determine analgesic effect. Oral administration of theacrine (8-32 mg/kg) induced dose-related anti-inflammatory and analgesic effects...
September 2010: Fitoterapia
https://www.readbyqxmd.com/read/17943563/theacrine-a-special-purine-alkaloid-with-sedative-and-hypnotic-properties-from-cammelia-assamica-var-kucha-in-mice
#12
Jie-Kun Xu, Hiroshi Kurihara, Liang Zhao, Xin-Sheng Yao
The central nervous system activities of theacrine (1,3,7,9-tetramethyluric acid), a purine alkaloid which is abundantly present in Camellia assamica var. kucha, were investigated in ambulatory activity, pentobarbital-induced sleep and forced swimming test in mice, compared with two other purine alkaloids, caffeine and theobromine. Caffeine treatment led to a marked increase in the ambulatory activity accompanied with decreasing of the immobility time in forced swimming test at both 10 and 30 mg/kg. Under the same conditions, neither theacrine nor theobromine showed obvious excited efficacy...
September 2007: Journal of Asian Natural Products Research
https://www.readbyqxmd.com/read/16663351/metabolic-relations-between-methylxanthines-and-methyluric-acids-in-coffea-l
#13
J B Petermann, T W Baumann
Metabolism of purine alkaloids in the leaves of Coffea dewevrei De Wild et Durand var excelsa Chev, Coffea liberica Bull ex Hiern and Coffea abeokutae Cramer was studied by analyzing leaf discs collected during vegetative development and by feeding the following radioactive tracers: [(14)C]theobromine, [(14)C]caffeine, and [(14)C]theacrine (1,3,7,9-tetramethyluric acid). Their principal metabolites were quantitatively and qualitatively determined. All three species convert the precursors to the same radioactive products, and proceed through the same four maturity stages characterized by the alkaloid accumulation pattern and by a particular transformation potency: (stage 1) young plant accumulating caffeine, transforms theobromine to caffeine; (stage 2) caffeine is gradually replaced by theacrine, theobromine and caffeine are converted to theacrine; (stage 3) theacrine disappears whereas liberine (O(2), 1,9-thrimethyluric acid) accumulates, theacrine is metabolized to liberine; (stage 4) branched-out plant containing liberine but no theacrine, caffeine is converted rapidly to liberine via theacrine...
December 1983: Plant Physiology
https://www.readbyqxmd.com/read/12009315/theacrine-1-3-7-9-tetramethyluric-acid-synthesis-in-leaves-of-a-chinese-tea-kucha-camellia-assamica-var-kucha
#14
Xin-Qiang Zheng, Chuang-Xing Ye, Misako Kato, Alan Crozier, Hiroshi Ashihara
Theacrine (1,3,7,9-tetramethyluric acid) and caffeine were the major purine alkaloids in the leaves of an unusual Chinese tea known as kucha (Camellia assamica var. kucha). Endogenous levels of theacrine and caffeine in expanding buds and young leaves were ca. 2.8 and 0.6-2.7% of the dry wt, respectively, but the concentrations were lower in the mature leaves. Radioactivity from S-adenosyl-L-[methyl-14C]methionine was incorporated into theacrine as well as theobromine and caffeine by leaf disks of kucha, indicating that S-adenosyl-L-methionine acts as the methyl donor not only for caffeine biosynthesis but also for theacrine production...
May 2002: Phytochemistry
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