Dai Nakae

Faculty of Health Care and Medical Sports,Department of Medical Sports,Animal Medical CourseProfessor
Last Updated :2025/10/07

■Researcher basic information

Degree

  • D.M.Sc., Nara Medical University, May 1989

Research Keyword

  • food factor
  • toxicologic pathology
  • Preventive Medicine
  • Animal Preventive Medicine
  • safety asessment
  • risk analysis
  • preneoplastic lesion
  • gene mutation
  • oxidative stress
  • choine-deficient, methionine-lowered, L-amino acid-defined diet
  • epigenetic carcinogenesis
  • species difference
  • gpt delta transgenic animal
  • endogenous carcinogenesis
  • 8-oxoguanine
  • heterocyclicamine
  • nitroso compound
  • environmental carcinogen
  • genetically modified animal
  • diethylnitrosamine
  • chemical caricnogenesis
  • environmental factor
  • carcinogen
  • toxicology

Field Of Study

  • Other, Other, risk assessment of chemicals
  • Other, Other, preventive medicine for animals and humans
  • Other, Other, toxicology/toxicologic pathology
  • Life sciences, Hygiene and public health (non-laboratory), public health
  • Life sciences, Nutrition and health science, nutritional and health science
  • Life sciences, Experimental pathology, experimental pathology

■Career

Career

  • Apr. 2022 - Present
    Teikyo Heisei University, Animal Medical Course, Department of Medical Sports, Faculty of Health Care and Medical Sports, Professor, M.D., D.M.Sc.
  • Apr. 2015 - Mar. 2022
    Tokyo University of Agriculture, Laboratory of Food Safety Assessment Science, Department of Nutritional Science and Food Safety, Faculty of Applied Biosciences, Professor, M.D., D.M.Sc.

■Research activity information

Award

  • Jun. 2025
    International Academy of Toxicologic Pathology, Leadership Excellence Award
    Asian Pacific Director
    Dai Nakae

Paper

MISC

Books and other publications

Lectures, oral presentations, etc.

  • Alternatives to animal experiments in the regulation of food, the Japanese situation               
    Nakae, D.
    ILSI 2021International Workshop for Non-animal Approaches in Food Sector, 21 Oct. 2021, [Invited]

Research Themes

  • Study on the Mechanisms Underlying Endogenous Hepatocarcinogenesis Induced Only by the Manipulation of Food Composition
    Grant-in-Aid for Scientific Research (C)
    Sasaki Institute, Sasaki Foundation
    2004 - 2005
    The present study assessed possible involvement of gene mutation in the early stage hepatocarcinogenesis, using gpt delta rats with a reporter transgene. In the study, 6-week-old male gpt delta rats originated from either Fischer 344 (F344) or Sprague-Dawley (SD) strains were used. Two rat hepatocarcinogenesis models were featured, an endogenous one with a choline-deficient L-amino acid-defined (CDAA) diet and an exogenous one with N-nitrosodiethylamine (DEN). Phenyl N-tert-butyl nitrone (PBN) was chosen as a negative modifier of hepatocarcinogenesis. The experiment was conducted by 15 groups each consisting of 6 animals (F344 for groups 1-8 and SD for groups 9-15). Groups 1, 2, 3 and 4 received the CDAA diet, CDAA+PBN (0.13% in drinking water), a choline-supplemented L-amino acid-defined (CSAA) diet and CSAA+PBN, respectively, from the end of week 2 for 16 weeks. Groups 5 and 6 received DEN of 2 weekly intraperitoneal doses of 100mg/kg body weight at the beginning. Only group 6 received PBN from the end of week 2 for 16 weeks. Groups 7 and 8 received vehicle in place of DEN and were similarly treated to groups 5 and 6, respectively. Groups 9-13, 14 and 15 were treated similarly to groups 1-5, 7 and 8, respectively. At the end of week 18, all animals were killed to obtain the liver for the examination for the development of preneoplastic lesion, oxidative DNA injury (8-oxoguanine, 8-oxoG) and gene mutation (gpt assay). In the endogenous model, the CDAA diet induced preneoplastic lesions only in F344. The 8-oxoG levels increased by the CDAA diet in both strains, F344 being higher than SD. The gene mutation increased by both the CDAA and CSAA diets with the same extent, only in F344. The CSAA diet predominantly caused GC/AT transition and deletion, while the CDAA diet caused those in association with GC/TA transversion, specific to 8-oxoG. PBN inhibited all changes caused by the CDAA diet but not gene mutation caused by the CSAA diet. In the exogenous model, DEN induced preneoplastic lesions more but smaller in F344 and more as well as larger in SD than the CDAA diet. The lesions were more in SD than in F344. The 8-oxoG levels increased by DEN in both strains, lower and higher than the CDAA case, respectively. The gene mutation increased by DEN, higher than the CDAA case, in both strains, higher in SD than in F344. PBN did not exert any influence on changes caused by DEN. These results indicate that the gene mutation is involved in both endogenous and exogenous rat hepatocarcinogenesis at its early stage but in different manners, and plays roles in the mechanisms underlying the strain difference.
  • Risk Assessment of Carcinogenesis due to Environmental Agents
    Grant-in-Aid for Scientific Research on Priority Areas
    Osaka City University Medical School
    1996 - 1999
    1) It was strongly suggested that a no observed effect level exists for rat liver carcinogenicity of diethylnitrosamine. 2) SCID mice proved useful for detection of 2-amino-3-methylimidazo [4,5-f] quinoline-low dose carcinogenicity. 3) Phenobarbital treatment to rats induced P450 and hydroxyradicals in the liver, resulting in increase of 8-hydroxyguanine (8-OHG) formation. 4) Further studies are required risk assessment for carcinogenesis using transgenic or knockout mice. 5) PLACE-SSCP method was examined to confirm the utility of detection for rare mutations of oncogenes or tumor suppressor genes related to cancer induction. 6) Mesurement of 8-OHG is important for risk assessment of carcinogenesis in animals.
  • Basic Research on the Development and Progression of Pancreatic Duct Adenocarcinoma
    Grant-in-Aid for Scientific Research (A)
    Nara Medical University
    1996 - 1999
    The importance of basic research related to pancreatic cancer should be focused on ductal adenocarcinoma since the incidence of * cancer is the highest, showing poor prognosis among various histological types of human pancreatic malignant neoplasms. However, experimental pancreatic duct adenocarcinoma (PDA) resembled histologically, biologically and genetically to human PDA can be induced by nitrosamines only in hamsters and dogs but not in other animal spieces. In this projects, we performed the research related to control the development and progression of PDA using a rapid production model of PDC in hamsters which was developed by us (Mizumoto, K. et al.,J.Natl.Cancer Inst.1998 ; 80 : 1564-1567) and PDA cell lines which were also established by us (Mori, T.et al.Int.J.Pancreao.1994 ; 16 : 171-177).
    Genetic alterations related to the development and progression of PDA
    1. The shortened telomeas and increased telomerase activities were detected in hamster PDA and also increased telomerase activities were detected in 32 out of 38 cases (84%) of human PDA tissues. Among those cases, Ki-ras mutations were also detected in 20 cases (53%).
    2. Midkine, one of growth factors, was overexpressed at mRNA level and also expressed at protein level in PDAs.
    3. MMP-2, one of MMP families, was importantly involved in the development and progression of PDAs.
    4. Bax, one of apoptosis related genes, was overexpressed in PDAs.
    5.β-catenine was not involved in the development and progression of PDAs.
    Possible control of PDA
    1. Possible involvement of heterocyclic amines of Trp-p-1 and DiMeIQx in the development of PDA was suggested.
    2. OPB-3206, a inhibition of MMPs, inhibited pancreatic duct carcinogenesis.
    3.β-carotin at a dose of 0.0025%, palm carotin at 0.004%, greentea polyphynol at 0.05 and 0.5%, 4-hydoxyphenyl retinamide (4-HPR) at 0.0015% and tranexamic acid at 0.1% in the diets inhibited pancreatic duct carcinogenesis.
    4. 4-HPR at the concentration of 10μ M and auraptene at 50μ M introduced apoptosis in culture PDA cells.

Media Coverage

  • Establishment of The Society of Preventive Medicine for Animals and Humans               
    SHOGAKUKAN, @DIME, https://dime.jp/genre/1819475/, Jul. 2024, Internet

■University education and qualification information

Qualifications, licenses

  • License for Medical Doctor 
  • Qualified M.D. to Perform Pathological Autopsy
  • Diplomate of the Japanese Society of Toxicologic Pathology
  • Certified Pathologist of The Japanese Society of Pathology
  • Fellow of the International  Academy  of  Toxicologic  Pathology
  • Instructor for Certified Pathologist of the Japanese Society of Pathology
  • Occupational Physician Certified by the Japan Medical Association
  • Board Certified Physician and Supervisory Physician for Public Health and Social Medicine
  • Board-Certified Doctor of Pathology
  • Expert of Cancer Prevention