A 90-Day Oral Toxicological Evaluation of the Methylurate Purine Alkaloid Theacrine

Amy Clewell, Gábor Hirka, Róbert Glávits, Philip A Palmer, John R Endres, Timothy S Murbach, Tennille Marx, Ilona Pasics Szakonyiné, Amy Clewell, Gábor Hirka, Róbert Glávits, Philip A Palmer, John R Endres, Timothy S Murbach, Tennille Marx, Ilona Pasics Szakonyiné

Abstract

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. In 375 mg/kg bw/day males, slight reductions in body weight development, food consumption, and feed efficiency, decreased weight of the testes and epididymides and decreased intensity of spermatogenesis in the testes, lack or decreased amount of mature spermatozoa in the epididymides, and decreased amount of prostatic secretions were detected at the end of the three months. At 300 mg/kg bw/day, slight decreases in the weights of the testes and epididymides, along with decreased intensity of spermatogenesis in the testes, and lack or decreased amount of mature spermatozoa in the epididymides were detected in male animals. The NOAEL was considered to be 180 mg/kg bw/day, as at this dose there were no toxicologically relevant treatment-related findings in male or female animals.

Figures

Figure 1
Figure 1
Intact (normal) hepatocytes around the central vein of a female rat at 375 mg/kg bw/day at terminal sacrifice. Haematoxylin and eosin staining; magnification 200x (a) and 400x (b).
Figure 2
Figure 2
Centrilobular necrosis (arrows) in the liver of a female rat at 300 mg/kg bw/day found dead on day 33. Haematoxylin and eosin staining; magnification 200x (a) and 400x (b).

References

    1. Petermann J. B., Baumann T. W. Metabolic relations between methylxanthines and methyluric acids in Coffea L. Plant Physiology. 1983;73(4):961–964. doi: 10.1104/pp.73.4.961.
    1. Ashihara H., Kato M., Crozier A. Distribution, biosynthesis and catabolism of methylxanthines in plants. In: Fredholm B. B., editor. Methylxanthines. Vol. 200. 2011. pp. 11–31. (Handbook of Experimental Pharmacology).
    1. Li K., Shi X., Yang X., Wang Y., Ye C., Yang Z. Antioxidative activities and the chemical constituents of two Chinese teas, Camellia kucha and C. ptilophylla . International Journal of Food Science and Technology. 2012;47(5):1063–1071. doi: 10.1111/j.1365-2621.2012.02942.x.
    1. Anaya A. L., Cruz-Ortega R., Waller G. R. Metabolism and ecology of purine alkaloids. Frontiers in Bioscience. 2006;11(1):2354–2370. doi: 10.2741/1975.
    1. Lim T. Edible Medicinal and Non-Medicinal Plants: Volume 3, Fruits. New York, NY, USA: Springer; 2012. Theobroma grandiflorum; pp. 252–258.
    1. Vasconcelos M., da Silva M., Maia J., Gottlieb O. Estudo químico de sementes do cupuaçu. Acta Amazônica. 1975;5(3):293–295.
    1. Baumann T., Wanner H. The 1,3,7,9-tetramethyluric acid content of cupu (Theobroma grandiflorum Schum.) Acta Amazônica. 1980;10(2):p. 425.
    1. Marx F., Maia J. G. S. Purine alkaloids in seeds of Theobroma species from the Amazon. Zeitschrift für Lebensmittel-Untersuchung und Forschung. 1991;193(5):460–461. doi: 10.1007/bf01187339.
    1. Xie G., He R.-R., Feng X., et al. The hypoglycemic effects of Camellia assamica var. kucha extract. Bioscience, Biotechnology and Biochemistry. 2010;74(2):405–407. doi: 10.1271/bbb.90618.
    1. Li S.-B., Li Y.-F., Mao Z.-F., et al. Differing chemical compositions of three teas may explain their different effects on acute blood pressure in spontaneously hypertensive rats. Journal of the Science of Food and Agriculture. 2015;95(6):1236–1242. doi: 10.1002/jsfa.6811.
    1. Zheng X.-Q., Ye C.-X., Kato M., Crozier A., Ashihara H. Theacrine (1,3,7,9-tetramethyluric acid) synthesis in leaves of a Chinese tea, kucha (Camellia assamica var. kucha) Phytochemistry. 2002;60(2):129–134. doi: 10.1016/s0031-9422(02)00086-9.
    1. Feduccia A. A., Wang Y., Simms J. A., et al. Locomotor activation by theacrine, a purine alkaloid structurally similar to caffeine: involvement of adenosine and dopamine receptors. Pharmacology Biochemistry and Behavior. 2012;102(2):241–248. doi: 10.1016/j.pbb.2012.04.014.
    1. Xu J.-K., Kurihara H., Zhao L., Yao X.-S. Theacrine, a special purine alkaloid with sedative and hypnotic properties from Cammelia assamica var. kucha in mice. Journal of Asian Natural Products Research. 2007;9(7):665–672. doi: 10.1080/10286020601103155.
    1. Wang Y., Yang X., Zheng X., Li J., Ye C., Song X. Theacrine, a purine alkaloid with anti-inflammatory and analgesic activities. Fitoterapia. 2010;81(6):627–631. doi: 10.1016/j.fitote.2010.03.008.
    1. Xie G., Wu M., Huang Y., et al. Experimental study of the acrine on antidepressant effects. Chinese Pharmacological Bulletin. 2009;9
    1. Li Y.-F., Chen M., Wang C., et al. Theacrine, a purine alkaloid derived from Camellia assamica var. kucha, ameliorates impairments in learning and memory caused by restraint-induced central fatigue. Journal of Functional Foods. 2015;16:472–483. doi: 10.1016/j.jff.2015.05.003.
    1. Li W.-X., Li Y.-F., Zhai Y.-J., Chen W.-M., Kurihara H., He R.-R. Theacrine, a purine alkaloid obtained from Camellia assamica var. kucha, attenuates restraint stress-provoked liver damage in mice. Journal of Agricultural and Food Chemistry. 2013;61(26):6328–6335. doi: 10.1021/jf400982c.
    1. Cauli O., Pinna A., Valentini V., Morelli M. Subchronic caffeine exposure induces sensitization to caffeine and cross-sensitization to amphetamine ipsilateral turning behavior independent from dopamine release. Neuropsychopharmacology. 2003;28(10):1752–1759. doi: 10.1038/sj.npp.1300240.
    1. Svenningsson P., Nomikos G. G., Fredholm B. B. The stimulatory action and the development of tolerance to caffeine is associated with alterations in gene expression in specific brain regions. The Journal of Neuroscience. 1999;19(10):4011–4022.
    1. Kihlman B. A. 1,3,7,9-Tetramethyluric acid—a chromosome-damaging agent occurring as a natural metabolite in certain caffeine-producing plants. Mutation Research/Reviews in Genetic Toxicology. 1977;39(3-4):297–315. doi: 10.1016/0165-1110(77)90010-0.
    1. Kihlman B. A., Odmark G. Deoxyribonucleic acid synthesis and the production of chromosomal aberrations by streptonigrin, 8-ethoxycaffeine and 1,3,7,9-tetramethyluric acid. Mutation Research—Fundamental and Molecular Mechanisms of Mutagenesis. 1965;2(6):494–505. doi: 10.1016/0027-5107(65)90015-1.
    1. Endres J., Deshmukh N., Glavitis R., et al. A comprehensive toxicological assessment of the purine alkaloid theacrine. The Toxicologist, Supplement to Toxicological Sciences. 2016;150(1) Abstract #1459.
    1. Hayward S., Mullins J., Urbina S., et al., editors. Safety of Teacrine™, a non-habituating, naturally-occuring purine alkaloid over eight weeks of continuous use. Proceedings of the Annual Meeting of the International Society of Sport Nutrition; 2015; Austin, Tex, USA.
    1. Taylor L., Mumford P., Roberts M., et al. Safety of TeaCrine®, a non-habituating, naturally-occurring purine alkaloid over eight weeks of continuous use. Journal of the International Society of Sports Nutrition. 2016;13, article 2 doi: 10.1186/s12970-016-0113-3.
    1. Habowski S. M., Sandrock J. E., Kedia A. W., Ziegenfuss T. N. The effects of Teacrine™, a nature-identical purine alkaloid, on subjective measures of cognitive function, psychometric and hemodynamic indices in healthy humans: a randomized, double-blinded crossover pilot trial. Journal of the International Society of Sports Nutrition. 2014;11(1, article P49) doi: 10.1186/1550-2783-11-s1-p49.
    1. Ziegenfuss T. N., Habowski S. M., Sandrock J. E., Kedia A. W., Kerksick C. M., Lopez H. L. A two-part approach to examine the effects of theacrine (TeaCrine®) supplementation on oxygen consumption, hemodynamic responses, and subjective measures of cognitive and psychometric parameters. Journal of Dietary Supplements. 2016 doi: 10.1080/19390211.2016.1178678.
    1. OECD. OECD 408. Guideline for the testing of chemicals: repeated dose 90-day oral toxicity study in rodents, Section 4, No. 408, adopted 21, pp. 1–10, September 1998.
    1. FDA. Toxicological Principles for the Safety Assessment of Food Ingredients. IV.C.4.a. Subchronic Toxicity Studies with Rodents. 2003.
    1. National Research Council. Guide for the Care and Use of Laboratory Animals. Washington, DC, USA: Committee for the Update of the Guide for the Care and Use of Laboratory Animals, Institute for Laboratory Animal Research, Division on Earth and Life Studies, National Research Council; 2011.
    1. Irwin S. Comprehensive observational assessment: Ia. A systematic, quantitative procedure for assessing the behavioral and physiologic state of the mouse. Psychopharmacologia. 1968;13(3):222–257. doi: 10.1007/BF00401402.
    1. Eustis S., Boorman G., Harada T., Popp J. Pathology of the Fischer Rat Reference and Atlas. San Diego, Calif, USA: Academic Press; 1990. Liver; pp. 71–94.
    1. Kapp R. W., Jr., Mendes O., Roy S., McQuate R. S., Kraska R. General and genetic toxicology of guayusa concentrate (Ilex guayusa) International Journal of Toxicology. 2016;35(2):222–242. doi: 10.1177/1091581815625594.
    1. OECD SIDS, Cafeine, CAS: 58-08-2, UNEP Publications, Paris, France, 2002.
    1. Onuegbu A. J., Olisekodiaka J. M., Adebolu O. E., Adesiyan A., Ayodele O. E. Coffee consumption could affect the activity of some liver enzymes and other biochemical parameters in healthy drinkers. Medical Principles and Practice. 2011;20(6):514–518. doi: 10.1159/000328420.
    1. Modi A. A., Feld J. J., Park Y., et al. Increased caffeine consumption is associated with reduced hepatic fibrosis. Hepatology. 2010;51(1):201–209. doi: 10.1002/hep.23279.
    1. Ruhl C. E., Everhart J. E. Coffee and caffeine consumption reduce the risk of elevated serum alanine aminotransferase activity in the United States. Gastroenterology. 2005;128(1):24–32. doi: 10.1053/j.gastro.2004.09.075.
    1. Ruhl C. E., Everhart J. E. Coffee and tea consumption are associated with a lower incidence of chronic liver disease in the United States. Gastroenterology. 2005;129(6):1928–1936. doi: 10.1053/j.gastro.2005.08.056.
    1. EFSA. Scientific opinion. Opinion on the safety of caffeine. The EFSA Journal. 2015;13(5)
    1. Gans J. H. Comparative toxicities of dietary caffeine and theobromine in the rat. Food and Chemical Toxicology. 1984;22(5):365–369. doi: 10.1016/0278-6915(84)90365-x.
    1. Funabashi H., Fujioka M., Kohchi M., Tateishi Y., Matsuoka N. Collaborative work to evaluate toxicity on male reproductive organs by repeated dose studies in rats. 22) effects of 2- and 4-week administration of theobromine on the testis. Journal of Toxicological Sciences. 2000;25:211–221. doi: 10.2131/jts.25.specialissue_211.
    1. Peck J. D., Leviton A., Cowan L. D. A review of the epidemiologic evidence concerning the reproductive health effects of caffeine consumption: a 2000–2009 update. Food and Chemical Toxicology. 2010;48(10):2549–2576. doi: 10.1016/j.fct.2010.06.019.
    1. Vandenberghe J. Life-Span Data and Historical Data in Carcinogenicity Testing in Wistar Rats Crl:(WI) BR. Addendum 5.8. Beerse, Belgium: Janssen Research Foundation, Department of Toxicology, Charles River Deutschland; 1990.
    1. Boorman G., Eustis S. Lung. In: Boorman G., Eustis S., Elwell M., MacKenzie W., editors. Pathology of the Fischer Rat: Reference and Atlas. San Diego, Calif, USA: Academic Press; 1990. pp. 339–367.
    1. Haschek W., Rousseaux C., Wallig M. Fundamentals of Toxicologic Pathology. New York, NY, USA: Elsevier; 2009. Respiratory system. Structure and cell biology. Physiology and functional considerations—lymphoid tissue; p. p. 98.
    1. Vidal J., Mirsky M., Colman K., Whitney K., Creasy D. Toxicologic Pathology Nonclinical Safety Assessment. chapter 18. Boca Raton, Fla, USA: CRC Press; 2013. Reproductive system and mammary gland; pp. 717–830.
    1. Hamlin M., Banas D. Pathology of the Fischer rat Reference and Atlas. San Diego, Calif, USA: Academic Press; 1990. Adrenal gland; pp. 501–518.
    1. Everds N. E., Snyder P. W., Bailey K. L., et al. Interpreting stress responses during routine toxicity studies: a review of the biology, impact, and assessment. Toxicologic Pathology. 2013;41(4):560–614. doi: 10.1177/0192623312466452.

Source: PubMed

3
Abonnere