著者
Ayumi TSUBOTA Yuko OKAMATSU-OGURA Jussiaea Valente BARIUAN Junnosuke MAE Shinya MATSUOKA Junko NIO-KOBAYASHI Kazuhiro KIMURA
出版者
JAPANESE SOCIETY OF VETERINARY SCIENCE
雑誌
Journal of Veterinary Medical Science (ISSN:09167250)
巻号頁・発行日
vol.81, no.10, pp.1461-1467, 2019 (Released:2019-10-24)
参考文献数
23
被引用文献数
9 9

Brown adipose tissue (BAT) contributes to non-shivering thermogenesis and plays an important role in body temperature control. The contribution of BAT thermogenesis to body temperature control in a non-cold environment was evaluated using developing hamsters. Immunostaining for uncoupling protein 1 (UCP1), a mitochondrial protein responsible for BAT thermogenesis, indicated that interscapular fat tissue had matured as BAT at day 14. When pups were placed on a thermal plate kept at 23°C, the body surface temperature decreased in day 7- and 10-day-old pups but was maintained at least for 15 min in 14-day-old pups, indicating that hamsters are unable to maintain their body temperature until around day 14 even in a non-cold environment. Body temperature maintenance was also evaluated in UCP1-deficient mice. BAT analysis showed that the UCP1 protein level in Ucp1+/− Hetero mice was 61.3 ± 1.4% of that in wild-type (WT) mice and was undetected in Ucp1−/− knockout (KO) mice. When 12-day-old pups were place on a thermal plate at 23°C, body surface temperature was maintained for at least 15 min in WT and Hetero mice but gradually dropped by 2.4 ± 0.2°C in 15 min in KO mice. It is concluded that BAT thermogenesis is indispensable for body temperature maintenance in pups of hamsters and mice, even in the non-cold circumstances. The early life poikilothermy and the later acquirement of homeothermy in hamsters may be because of the postnatal development of BAT.
著者
Masako YAJIMA Shin-Ichiro KARAKI Takeshi TSURUTA Shunsuke KIMURA Junko NIO-KOBAYASHI Atsukazu KUWAHARA Takaji YAJIMA
出版者
バイオメディカルリサーチプレス
雑誌
Biomedical Research (ISSN:03886107)
巻号頁・発行日
vol.37, no.5, pp.319-328, 2016-10-01 (Released:2016-10-25)
参考文献数
41
被引用文献数
12

Non-neuronal and atropine-sensitive ileal contractile responses to short chain fatty acids (SCFAs) are detected in the neonatal stage, and change with age or inflammatory conditions. However, the roles of luminal SCFAs in developmental changes have not yet been elucidated. We examined ileal contractile responses to SCFAs in mice colonized with different SCFA-producing intestinal microbiota under normal and inflammatory conditions. Using conventional (Conv), germ-free (GF), and gnotobiotic mice infected with Bifidobacterium (GB-bif), Propionibacterium (GB-prop), or Lactobacillus (GB-lact), ileal contractions were measured in 1-day-old neonates and 7-week-old mice using an isotonic transducer. Contractions occurred in all 1-day-old neonates, and were significantly desensitized in the adult stage in the Conv, GB-bif, and GB-prop groups, but not in the GF and GB-lact groups. An injection of lipopolysaccharide frequently restored desensitized contractions; however, the contraction rate did not change in the GF and GB-lact groups. The relative mRNA expression of a SCFA receptor (GPR43) or nicotinic acetylcholine receptor α7 was weaker in the GF group (0.3-fold or 0.4-fold expression level, respectively) than in the Conv group. In conclusion, the luminal inhabitation of SCFA-producing bacteria may potentiate the regulation of non-neuronal and atropine-sensitive ileal contractile responses to SCFAs under healthy and inflammatory conditions.