NTP REPORT ON THE TOXICOLOGY STUDY OF SENNA (CAS NO. 8013-11-4) IN C57BL/6NTAC MICE AND TOXICOLOGY AND CARCINOGENESIS STUDY OF SENNA IN GENETICALLY MODIFIED C3B6.129F1/Tac-Trp53tm1Brd N12 HAPLOINSUFFICIENT MICE (FEED STUDIES) NATIONAL TOXICOLOGY PROGRAM P.O. Box 12233 Research Triangle Park, NC 27709 April 2012 NTP GMM 15 NIH Publication No. 12-5968 National Institutes of Health Public Health Service U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES FOREWORD The National Toxicology Program (NTP) is an interagency program within the Public Health Service (PHS) of the Department of Health and Human Services (HHS) and is headquartered at the National Institute of Environmental Health Sciences of the National Institutes of Health (NIEHS/NIH). Three agencies contribute resources to the program: NIEHS/NIH, the National Institute for Occupational Safety and Health of the Centers for Disease Control and Prevention (NIOSH/CDC), and the National Center for Toxicological Research of the Food and Drug Administration (NCTR/FDA). Established in 1978, the NTP is charged with coordinating toxicological testing activities, strengthening the science base in toxicology, developing and validating improved testing methods, and providing information about potentially toxic substances to health regulatory and research agencies, scientific and medical communities, and the public. The Genetically Modified Model (GMM) Report series began in 2005 with studies conducted by the NTP. The studies described in the GMM Report series are designed and conducted to characterize and evaluate the toxicologic potential, including carcinogenic activity, of selected agents in laboratory animals that have been genetically modified. These genetic modifications may involve inactivation of selected tumor suppressor functions or activation of oncogenes that are commonly observed in human cancers. This may result in a rapid onset of cancer in the genetically modified animal when exposure is to agents that act directly or indirectly on the affected pathway. An absence of a carcinogenic response may reflect either an absence of carcinogenic potential of the agent or that the selected model does not harbor the appropriate genetic modification to reduce tumor latency and allow detection of carcinogenic activity under the conditions of these subchronic studies. Substances selected for NTP toxicity and carcinogenicity studies are chosen primarily on the basis of human exposure, level of production, and chemical structure. The interpretive conclusions presented in NTP GMM Reports are based only on the results of these NTP studies. Extrapolation of these results to other species, including characterization of hazards and risks to humans, requires analyses beyond the intent of these reports. Selection per se is not an indicator of a substance’s carcinogenic potential. The NTP conducts its studies in compliance with its laboratory health and safety guidelines and FDA Good Laboratory Practice Regulations and must meet or exceed all applicable federal, state, and local health and safety regulations. Animal care and use are in accordance with the Public Health Service Policy on Humane Care and Use of Animals. Studies are subjected to retrospective quality assurance audits before being presented for public review. NTP GMM Reports are indexed in the NIH/NLM PubMed database and are available free of charge electronically on the NTP website (http://ntp.niehs.nih.gov) or in hardcopy upon request from the NTP Central Data Management group at [email protected] or (919) 541-3419. NTP REPORT ON THE TOXICOLOGY STUDY OF SENNA (CAS NO. 8013-11-4) IN C57BL/6NTAC MICE AND TOXICOLOGY AND CARCINOGENESIS STUDY OF SENNA IN GENETICALLY MODIFIED C3B6.129F1/Tac-Trp53tm1Brd N12 HAPLOINSUFFICIENT MICE (FEED STUDIES) NATIONAL TOXICOLOGY PROGRAM P.O. Box 12233 Research Triangle Park, NC 27709 April 2012 NTP GMM 15 NIH Publication No. 12-5968 National Institutes of Health Public Health Service U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES 2 CONTRIBUTORS National Toxicology Program NTP Pathology Working Group Evaluated and interpreted results and reported findings Evaluated slides and contributed to pathology report on 40-week mice (July 24, 2009) I. Surh, Ph.D., Study Scientist J.K. Dunnick, Ph.D., Study Scientist W.G. Lieuallen, D.V.M., Ph.D., Coordinator Pathology Associates, A Charles River Company A.E. Brix, D.V.M., Ph.D., Study Pathologist Experimental Pathology Laboratories, Inc. N. Allison, D.V.M. J.B. Bishop, Ph.D. Experimental Pathology Laboratories, Inc. R.S. Chhabra, Ph.D. S.A. Elmore, D.V.M., M.S. National Toxicology Program P.M. Foster, Ph.D. M.J. Hoenerhoff, D.V.M., Ph.D. J.E. French, Ph.D. National Toxicology Program R.A. Herbert, D.V.M., Ph.D. D.E. Malarkey, D.V.M., Ph.D. M.J. Hooth, Ph.D. National Toxicology Program A.P. King-Herbert, D.V.M. R.R. Maronpot, D.V.M. G.E. Kissling, Ph.D. Experimental Pathology Laboratories, Inc. D.E. Malarkey, D.V.M., Ph.D. J.C. Peckham, D.V.M., M.S., Ph.D. J.M. Sanders, Ph.D. Experimental Pathology Laboratories, Inc. C.S. Smith, Ph.D. D. Vasconcelos, D.V.M., Ph.D. Battelle Columbus Operations G.S. Travlos, D.V.M. M.K. Vallant, B.S., M.T. N.J. Walker, Ph.D. SRA International, Inc. Provided statistical analyses K.L. Witt, M.S. P.W. Crockett, Ph.D., Principal Investigator Battelle Columbus Operations L.J. Betz, M.S. Conducted studies and evaluated pathology findings K.P. McGowan, M.B.A. M.R. Hejtmancik, Ph.D., Principal Investigator Biotechnical Services, Inc. D. Vasconcelos, D.V.M., Ph.D. Prepared Report Experimental Pathology Laboratories, Inc. S.R. Gunnels, M.A., Principal Investigator Provided pathology review L.M. Harper, B.S. T.S. Kumpe, M.A. M.H. Hamlin, II, D.V.M., Principal Investigator J.I. Powers, M.A.P. N. Allison, D.V.M. D.C. Serbus, Ph.D. J.C. Peckham, D.V.M., M.S., Ph.D. Dynamac Corporation Prepared quality assessment audits S. Brecher, Ph.D., Principal Investigator S. Iyer, B.S. V.S. Tharakan, D.V.M. 3 CONTENTS ABSTRACT ................................................................................................................................................................. 5 EXPLANATION OF LEVELS OF EVIDENCE OF CARCINOGENIC ACTIVITY .......................................... 8 PEER REVIEW PANEL ............................................................................................................................................ 9 SUMMARY OF PEER REVIEW PANEL COMMENTS ..................................................................................... 10 INTRODUCTION ..................................................................................................................................................... 11 MATERIALS AND METHODS .............................................................................................................................. 23 RESULTS ................................................................................................................................................................... 31 DISCUSSION AND CONCLUSIONS ..................................................................................................................... 43 REFERENCES .......................................................................................................................................................... 45 APPENDIX A Summary of Lesions in Heterozygous F1 p53+/− Mice in the 40-Week Feed Study of Senna .......................................................................................................................................... 55 APPENDIX B Genetic Toxicology ........................................................................................................................ 69 APPENDIX C Organ Weights and Organ-Weight-to-Body-Weight Ratios ..................................................... 81 APPENDIX D Chemical Characterization and Dose Formulation Studies ...................................................... 85 APPENDIX E Feed and Compound Consumption in the 40-Week Feed Study of Senna ............................... 97 APPENDIX F Historical Control Incidences ..................................................................................................... 103 APPENDIX G Ingredients, Nutrient Composition, and Contaminant Levels In NTP-2000 Rat and Mouse Ration ......................................................................................... 107 APPENDIX H Sentinel Animal Program .......................................................................................................... 111 4 Senna, NTP GMM 15 SUMMARY Background Senna is a plant product used in laxatives. We tested senna in a genetically modified mouse strain that shows tumor responses more rapidly than in standard mouse strains. Methods We gave groups of male or female heterozygous F1 p53+/− mice feed that contained senna plant material at concentrations of 100, 300, 1,000, 3,000, or 10,000 parts per million for 40 weeks. Tissues from 22 organs were examined for every animal. Results Epithelial hyperplasia of the large intestine was seen in all the mice receiving the top dose of 10,000 ppm (1%) senna in the feed. The incidences of cancer were not significantly increased in any of the tissues examined. Conclusions We conclude that senna caused epithelial hyperplasia of the large intestine in male and female F1 p53+/− mice. Senna exposure for 40 weeks did not cause any cancers in this mouse strain. 5 ABSTRACT SENNA CAS No. 8013-11-4 [Senna drawing obtained from Samuelsson (1999)] Synonyms: Alexandrian