- 著者
- Shuichi CHIBA Masatoshi SUZUKI Keitaro YAMANOUCHI Masugi NISHIHARA
- 出版者
- The Society for Reproduction and Development
- 雑誌
- Journal of Reproduction and Development (ISSN:09168818)
- 巻号頁・発行日
- vol.53, no.2, pp.297-307, 2007 (Released:2007-05-12)
- 参考文献数
- 54
- 被引用文献数
- 43 54
Recent studies have demonstrated the presence of neurogenesis in the adult mammalian hippocampus, and it has been suggested that estrogen and various growth factors influence the processes of adult neurogenesis. The present study assessed cell proliferation in the dentate gyrus and the mRNA expression levels of granulin, insulin-like growth factor-I (IGF-I), and brain-derived neurotrophic factor (BDNF) in the hippocampus 4 h after treatment with estradiol benzoate (EB) in 3- and 12-month old ovariectomized rats. At 3 months of age, mRNA expression of granulin precursor and cell proliferation were increased by EB treatment, although the mRNA expressions of IGF-I and BDNF remained unchanged. At 12 months of age, however, neither mRNA expression of the three genes nor cell proliferation in the dentate gyrus were affected by EB treatment. In addition, 17β-estradiol enhanced the proliferation of neural progenitor cells derived from hippocampal tissue of 3-month-old female rats in vitro; this was inhibited by neutralization of granulin with specific antibody. These results suggest that estrogen induces granulin gene expression in the hippocampus and that the product of this gene is involved in the mitogenic effects of estrogen in the dentate gyrus, although the responses to estrogen decline with age.
- 著者
- Hidetoshi Sugihara Koichi Kimura Keitaro Yamanouchi Naomi Teramoto Tomoko Okano Masao Daimon Hiroyuki Morita Katsu Takenaka Takanori Shiga Jun Tanihata Yoshitsugu Aoki Tokiko Inoue-Nagamura Hiroshi Yotsuyanagi Issei Komuro
- 出版者
- International Heart Journal Association
- 雑誌
- International Heart Journal (ISSN:13492365)
- 巻号頁・発行日
- pp.20-372, (Released:2020-11-13)
- 参考文献数
- 25
- 被引用文献数
- 8
Duchenne muscular dystrophy (DMD) is X-linked recessive myopathy caused by mutations in the dystrophin gene. Although conventional treatments have improved their prognosis, inevitable progressive cardiomyopathy is still the leading cause of death in patients with DMD. To explore novel therapeutic options, a suitable animal model with heart involvement has been warranted.We have generated a rat model with an out-of-frame mutation in the dystrophin gene using CRISPR/Cas9 genome editing (DMD rats). The aim of this study was to evaluate their cardiac functions and pathologies to provide baseline data for future experiments developing treatment options for DMD.In comparison with age-matched wild rats, 6-month-old DMD rats showed no significant differences by echocardiographic evaluations. However, 10-month-old DMD rats showed significant deterioration in left ventricular (LV) fractional shortening (P = 0.024), and in tissue Doppler peak systolic velocity (Sa) at the LV lateral wall (P = 0.041) as well as at the right ventricular (RV) free-wall (P = 0.004). These functional findings were consistent with the fibrotic distributions by histological analysis.Although the cardiac phenotype was milder than anticipated, DMD rats showed similar distributions and progression of heart involvement to those of patients with DMD. This animal may be a useful model with which to develop effective drugs and to understand the underlying mechanisms of progressive heart failure in patients with DMD.
- 著者
- Takahiro MIYOSHI Shin-ichi NAKANO Katsuyuki NAKAMURA Keitaro YAMANOUCHI Masugi NISHIHARA
- 出版者
- 公益社団法人 日本獣医学会
- 雑誌
- Journal of Veterinary Medical Science (ISSN:09167250)
- 巻号頁・発行日
- pp.12-0195, (Released:2012-05-31)
- 被引用文献数
- 1 5
Adult urodele amphibians such as newts are capable of regenerating lost structures including their limbs. In these species, dedifferentiation of myofiber is essential for the regenerative process. Upon terminal differentiation, nuclei of myofiber (myonuclei) are withdrawn from cell cycle, but prior to dedifferentiation, myonuclei reenter the cell cycle. In contrast with urodele amphibians, it is generally accepted that mammalian myofibers are not able to dedifferentiate in response to muscle injury. A recent study has suggested that electroporation can induce dedifferentiation response of skeletal muscle in newt limbs. In the present study, we examined whether myonuclei of skeletal muscle of mammals are capable of reentering the cell cycle by means of electroporation. Electroporation was applied to tibialis anterior muscle of the rat with or without plasmid DNA. Histological analyses revealed that, while electroporation induces degenerative/regenerative responses in skeletal muscle irrespective of the presence of plasmid DNA, the expression of proliferating cell nuclear antigen (PCNA) in myonuclei was observed only in the presence of plasmid DNA. The present results indicate that myonuclei of skeletal muscle are capable of reentering the cell cycle and suggest that in vivo electroporation can induce dedifferentiation of mammalian skeletal muscle.