bims-ciryme Biomed News
on Circadian rhythms and metabolism
Issue of 2019‒08‒04
two papers selected by
Gabriela Da Silva Xavier
University of Birmingham

  1. Trends Endocrinol Metab. 2019 Jul 31. pii: S1043-2760(19)30149-3. [Epub ahead of print]
    Miyake T, Doi M.
      Recently Koronowski et al. (Cell, 2019) showed that reconstitution of the liver circadian clock in otherwise genetically arrhythmic mice revives the daily program of the nicotinamide adenine dinucleotide salvage pathway and glycogenesis in vivo. This liver-autonomous metabolic cycling cannot be sustained under constant darkness, revealing the importance of the daily light cycle to restore liver function.
    Keywords:  Bmal1; autonomy; circadian; diurnal physiology; light; liver metabolism; systemic signaling
  2. Sci Rep. 2019 Jul 29. 9(1): 10909
    Sawai Y, Okamoto T, Muranaka Y, Nakamura R, Matsumura R, Node K, Akashi M.
      Lithium has been used as a mood stabilizer to treat human bipolar disorders for over half a century. Several studies have suggested the possibility that the efficacy of lithium treatment results in part from the amelioration of circadian dysfunction. However, the effect of lithium on clock gene expression has not yet been investigated in vivo because continuous measurement of gene expression in organs with high time resolution over a period of several days is difficult. To resolve this issue, we attached a small photo multiplier tube (PMT) tightly to the body surface of transgenic mice carrying a reporter gene such that the photon input window faced target organs such as the liver and kidney and succeeded in long-term continuous measurement of circadian gene expression in semi-freely moving mice over periods of several weeks. Using this simple method, we clearly showed that lithium causes circadian period elongation in peripheral clock gene expression rhythms in vivo. Further development of our detection system to maturity will aid a wide range of research fields in medicine and biology.