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Shigenobu Shibata - One of the best experts on this subject based on the ideXlab platform.
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forced rather than voluntary exercise entrains peripheral clocks via a corticosterone noradrenaline increase in per2 luc mice
Scientific Reports, 2016Co-Authors: Hiroyuki Sasaki, Yuko Ikeda, Yu Tahara, Mayo Kamagata, Yuta Hattori, Shinnosuke Yasuda, Shiho Iwami, Shigenobu ShibataAbstract:Exercise during the inactive period can entrain locomotor activity and peripheral circadian clock rhythm in mice; however, mechanisms underlying this entrainment are yet to be elucidated. Here, we showed that the bioluminescence rhythm of peripheral clocks in PER2::LUC mice was strongly entrained by forced treadmill and forced wheel-running exercise rather than by voluntary wheel-running exercise at middle time during the inactivity period. Exercise-induced entrainment was accompanied by increased levels of serum corticosterone and norepinephrine in peripheral tissues, similar to the physical stress-induced response. Adrenalectomy with norepinephrine receptor blockers completely blocked the treadmill exercise-induced entrainment. The entrainment of the peripheral clock by exercise is independent of the suprachiasmatic nucleus clock, the Main Oscillator in mammals. The present results suggest that the response of forced exercise, but not voluntary exercise, may be similar to that of stress, and possesses the entrainment ability of peripheral clocks through the activation of the adrenal gland and the sympathetic nervous system.
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2 2 2 tribromoethanol phase shifts the circadian rhythm of the liver clock in per2 luciferase knockin mice lack of dependence on anesthetic activity
Journal of Pharmacology and Experimental Therapeutics, 2012Co-Authors: Yuji Kubo, Yu Tahara, Akiko Hirao, Shigenobu ShibataAbstract:Comprehensive gene expression profiling in mice in response to the inhalation of sevoflurane has revealed that circadian clock gene expression is affected strongly in the liver, heart, lung, and kidney, in this order, but moderately in the spleen and slightly in the brain. Therefore, we examined whether the administration of general anesthetics at different times of the day induces phase shifts of the liver clock in Per2::Luciferase knockin mice. One to 4 days of intraperitoneal injection of 2,2,2-tribromoethanol (240 mg/kg, anesthetic time 60 min) or 2,2,2-trichloroethanol (240 mg/kg, 60 min), common anesthetics in veterinary surgery, caused phase delays when injected during the daytime and phase advances when injected during the nighttime. Inhalation administration of isoflurane for 30 or 60 min during the daytime did not induce a phase delay. Injection of propofol (300 mg/kg, 17 min) during the daytime induced an insignificant phase delay of the Per2 bioluminescence rhythm. Injection of 2,2,2-tribromoethanol did not induce a phase shift in the suprachiasmatic nucleus, the Main Oscillator, or in behavioral locomotor rhythms, suggesting that 2,2,2-tribromoethanol induced phase shifts of the liver clock independent of the Main suprachiasmatic clock. The expression of clock genes, such as Bmal1 and Clock, in mouse liver was decreased strongly 1 and 4 h after a single injection of 2,2,2-tribromoethanol. These results demonstrate that 2,2,2-tribromoethanol or 2,2,2-trichloroethanol produce phase shifts of the peripheral clock, independent of anesthetic activity. These anesthetics may cause circadian rhythm disorders in peripheral organs when administered as general anesthetics several times during the day.
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constant light housing attenuates circadian rhythms of mper2 mrna and mper2 protein expression in the suprachiasmatic nucleus of mice
Neuroscience, 2003Co-Authors: M Sudo, Takahiro Moriya, Masashi Akiyama, K Sasahara, Toshiyuki Hamada, Shigenobu ShibataAbstract:Constant light (LL) or constant dark (DD) environmental lighting conditions cause a free-running period and activity reduction in the rodent behavioral circadian rhythm. In order to understand the molecular process underlying behavioral rhythms in LL or DD housing conditions, we examined the circadian profile of mPer2 mRNA and mPER2 in the suprachiasmatic nucleus (SCN), a Main Oscillator, of free-running mice. The circadian expression rhythm of mPer2 in the SCN was dampened under 7-day LL conditions, whereas that of mPER2 protein was moderately attenuated and its expression peak delayed. The circadian expression of mPer2 and its product was slightly attenuated and advanced by 7-day DD conditions. With arrhythmic behavioral activity caused by long-term LL housing, mPER2 protein lost its rhythmicity in the SCN. On the other hand, LL or DD housing did not affect the mPer2 gene and its product in the cerebral cortex. The present results suggest that mPER2 circadian expression in the SCN corresponds well with behavioral circadian oscillation under LL or DD conditions. Thus, the behavioral circadian rhythm seems to correlate with molecular clock works in the SCN.
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restricted feeding entrains liver clock without participation of the suprachiasmatic nucleus
Genes to Cells, 2001Co-Authors: Reiko Hara, Hisanori Wakamatsu, Reiko Aida, Takahiro Moriya, Masashi Akiyama, Shigenobu ShibataAbstract:Background There are two Main stimuli that entrain the circadian rhythm, the light-dark cycle (LD) and restricted feeding (RF). Light-induced entrainment requires induction of the Per1 and Per2 genes in the suprachiasmatic nucleus (SCN), the locus of a Main Oscillator. In this experiment, we determined whether RF resets the expression of circadian clock genes in the mouse liver with or without participation of the SCN. Results Mice were allowed access to food for 4 h during the daytime (7 h advance of feeding time) under LD or constant darkness (DD). The peaks of mPer1, mPer2, D-site-binding protein (Dbp) and cholesterol 7α-hydroxylase (Cyp7A) mRNA in the liver were advanced 6–12 h after 6 days of RF, whereas those in SCN were unaffected. The advance of mPer expression in the liver by RF was still observed in SCN-lesioned mice. A 7 h advance in the LD cycle advanced the peaks of clock gene expression in both the liver and SCN, whereas, a shift in the LD did not move the phase of the liver clock when the shift was carried out under a fixed RF schedule during the night-time. Conclusions These results suggest that restricted feeding strongly entrained the expression of circadian clock genes in the liver without the participation of an SCN clock function.
Latham, Christian A. - One of the best experts on this subject based on the ideXlab platform.
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Kic 9246715: The Double Red Giant Eclipsing Binary with Odd Oscillations
'American Astronomical Society', 2016Co-Authors: Rawls, Meredith L., Gaulme Patrick, Mckeever Jean, Jackiewicz Jason, Orosz, Jerome A., Corsaro Enrico, Beck, Paul G., Mosser Benoît, Latham, David W., Latham, Christian A.Abstract:International audienceWe combine Kepler photometry with ground-based spectra to present a comprehensive dynamical model of the double red giant eclipsing binary KIC 9246715. While the two stars are very similar in mass (${M}_{1}={2.171}_{-0.008}^{+0.006}\ {M}_{\odot }$, ${M}_{2}={2.149}_{-0.008}^{+0.006}\ {M}_{\odot }$) and radius (${R}_{1}={8.37}_{-0.07}^{+0.03}\ {R}_{\odot }$, ${R}_{2}={8.30}_{-0.03}^{+0.04}\ {R}_{\odot }$), an asteroseismic analysis finds one Main set of solar-like oscillations with unusually low-amplitude, wide modes. A second set of oscillations from the other star may exist, but this marginal detection is extremely faint. Because the two stars are nearly twins, KIC 9246715 is a difficult target for a precise test of the asteroseismic scaling relations, which yield M = 2.17 ± 0.14 M⊙ and R = 8.26 ± 0.18 R⊙. Both stars are consistent with the inferred asteroseismic properties, but we suspect the Main Oscillator is Star 2 because it is less active than Star 1. We find evidence for stellar activity and modest tidal forces acting over the 171 day eccentric orbit, which are likely responsible for the essential lack of solar-like oscillations in one star and weak oscillations in the other. Mixed modes indicate the Main oscillating star is on the secondary red clump (a core-He-burning star), and stellar evolution modeling supports this with a coeval history for a pair of red clump stars. This system is a useful case study and paves the way for a detailed analysis of more red giants in eclipsing binaries, an important benchmark for asteroseismology
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KIC 9246715: The Double Red Giant Eclipsing Binary With Odd Oscillations
'American Astronomical Society', 2015Co-Authors: Rawls, Meredith L., Gaulme Patrick, Mckeever Jean, Jackiewicz Jason, Orosz, Jerome A., Corsaro Enrico, Latham, David W., Beck Paul, Mosser Benoît, Latham, Christian A.Abstract:We combine Kepler photometry with ground-based spectra to present a comprehensive dynamical model of the double red giant eclipsing binary KIC 9246715. While the two stars are very similar in mass (M1 = 2.171 [+0.006 / -0.008], M2 = 2.149 [+0.006 / -0.008] Msun) and radius (R1 = 8.37 [+0.03 / -0.07], R2 = 8.30 [+0.04 / -0.03] Rsun), an asteroseismic analysis finds one Main set of solar-like oscillations with unusually low-amplitude, wide modes. A second set of oscillations from the other star may exist, but this marginal detection is extremely faint. Because the two stars are nearly twins, KIC 9246715 is a difficult target for a precise test of the asteroseismic scaling relations, which yield M = 2.17 +/- 0.14 Msun and R = 8.26 +/- 0.18 Rsun. Both stars are consistent with the inferred asteroseismic properties, but we suspect the Main Oscillator is Star 2 because it is less active than Star 1. We find evidence for stellar activity and modest tidal forces acting over the 171-day eccentric orbit, which are likely responsible for the essential lack of solar-like oscillations in one star and weak oscillations in the other. Mixed modes indicate the Main oscillating star is on the secondary red clump (a core-He-burning star), and stellar evolution modeling supports this with a coeval history for a pair of red clump stars. This system is a useful case study and paves the way for a detailed analysis of more red giants in eclipsing binaries, an important benchmark for asteroseismology.Comment: 20 pages, 12 figures, 4 tables; accepted for publication in The Astrophysical Journa
Yu Tahara - One of the best experts on this subject based on the ideXlab platform.
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forced rather than voluntary exercise entrains peripheral clocks via a corticosterone noradrenaline increase in per2 luc mice
Scientific Reports, 2016Co-Authors: Hiroyuki Sasaki, Yuko Ikeda, Yu Tahara, Mayo Kamagata, Yuta Hattori, Shinnosuke Yasuda, Shiho Iwami, Shigenobu ShibataAbstract:Exercise during the inactive period can entrain locomotor activity and peripheral circadian clock rhythm in mice; however, mechanisms underlying this entrainment are yet to be elucidated. Here, we showed that the bioluminescence rhythm of peripheral clocks in PER2::LUC mice was strongly entrained by forced treadmill and forced wheel-running exercise rather than by voluntary wheel-running exercise at middle time during the inactivity period. Exercise-induced entrainment was accompanied by increased levels of serum corticosterone and norepinephrine in peripheral tissues, similar to the physical stress-induced response. Adrenalectomy with norepinephrine receptor blockers completely blocked the treadmill exercise-induced entrainment. The entrainment of the peripheral clock by exercise is independent of the suprachiasmatic nucleus clock, the Main Oscillator in mammals. The present results suggest that the response of forced exercise, but not voluntary exercise, may be similar to that of stress, and possesses the entrainment ability of peripheral clocks through the activation of the adrenal gland and the sympathetic nervous system.
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2 2 2 tribromoethanol phase shifts the circadian rhythm of the liver clock in per2 luciferase knockin mice lack of dependence on anesthetic activity
Journal of Pharmacology and Experimental Therapeutics, 2012Co-Authors: Yuji Kubo, Yu Tahara, Akiko Hirao, Shigenobu ShibataAbstract:Comprehensive gene expression profiling in mice in response to the inhalation of sevoflurane has revealed that circadian clock gene expression is affected strongly in the liver, heart, lung, and kidney, in this order, but moderately in the spleen and slightly in the brain. Therefore, we examined whether the administration of general anesthetics at different times of the day induces phase shifts of the liver clock in Per2::Luciferase knockin mice. One to 4 days of intraperitoneal injection of 2,2,2-tribromoethanol (240 mg/kg, anesthetic time 60 min) or 2,2,2-trichloroethanol (240 mg/kg, 60 min), common anesthetics in veterinary surgery, caused phase delays when injected during the daytime and phase advances when injected during the nighttime. Inhalation administration of isoflurane for 30 or 60 min during the daytime did not induce a phase delay. Injection of propofol (300 mg/kg, 17 min) during the daytime induced an insignificant phase delay of the Per2 bioluminescence rhythm. Injection of 2,2,2-tribromoethanol did not induce a phase shift in the suprachiasmatic nucleus, the Main Oscillator, or in behavioral locomotor rhythms, suggesting that 2,2,2-tribromoethanol induced phase shifts of the liver clock independent of the Main suprachiasmatic clock. The expression of clock genes, such as Bmal1 and Clock, in mouse liver was decreased strongly 1 and 4 h after a single injection of 2,2,2-tribromoethanol. These results demonstrate that 2,2,2-tribromoethanol or 2,2,2-trichloroethanol produce phase shifts of the peripheral clock, independent of anesthetic activity. These anesthetics may cause circadian rhythm disorders in peripheral organs when administered as general anesthetics several times during the day.
Yuji Kubo - One of the best experts on this subject based on the ideXlab platform.
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2 2 2 tribromoethanol phase shifts the circadian rhythm of the liver clock in per2 luciferase knockin mice lack of dependence on anesthetic activity
Journal of Pharmacology and Experimental Therapeutics, 2012Co-Authors: Yuji Kubo, Yu Tahara, Akiko Hirao, Shigenobu ShibataAbstract:Comprehensive gene expression profiling in mice in response to the inhalation of sevoflurane has revealed that circadian clock gene expression is affected strongly in the liver, heart, lung, and kidney, in this order, but moderately in the spleen and slightly in the brain. Therefore, we examined whether the administration of general anesthetics at different times of the day induces phase shifts of the liver clock in Per2::Luciferase knockin mice. One to 4 days of intraperitoneal injection of 2,2,2-tribromoethanol (240 mg/kg, anesthetic time 60 min) or 2,2,2-trichloroethanol (240 mg/kg, 60 min), common anesthetics in veterinary surgery, caused phase delays when injected during the daytime and phase advances when injected during the nighttime. Inhalation administration of isoflurane for 30 or 60 min during the daytime did not induce a phase delay. Injection of propofol (300 mg/kg, 17 min) during the daytime induced an insignificant phase delay of the Per2 bioluminescence rhythm. Injection of 2,2,2-tribromoethanol did not induce a phase shift in the suprachiasmatic nucleus, the Main Oscillator, or in behavioral locomotor rhythms, suggesting that 2,2,2-tribromoethanol induced phase shifts of the liver clock independent of the Main suprachiasmatic clock. The expression of clock genes, such as Bmal1 and Clock, in mouse liver was decreased strongly 1 and 4 h after a single injection of 2,2,2-tribromoethanol. These results demonstrate that 2,2,2-tribromoethanol or 2,2,2-trichloroethanol produce phase shifts of the peripheral clock, independent of anesthetic activity. These anesthetics may cause circadian rhythm disorders in peripheral organs when administered as general anesthetics several times during the day.
Rawls, Meredith L. - One of the best experts on this subject based on the ideXlab platform.
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Kic 9246715: The Double Red Giant Eclipsing Binary with Odd Oscillations
'American Astronomical Society', 2016Co-Authors: Rawls, Meredith L., Gaulme Patrick, Mckeever Jean, Jackiewicz Jason, Orosz, Jerome A., Corsaro Enrico, Beck, Paul G., Mosser Benoît, Latham, David W., Latham, Christian A.Abstract:International audienceWe combine Kepler photometry with ground-based spectra to present a comprehensive dynamical model of the double red giant eclipsing binary KIC 9246715. While the two stars are very similar in mass (${M}_{1}={2.171}_{-0.008}^{+0.006}\ {M}_{\odot }$, ${M}_{2}={2.149}_{-0.008}^{+0.006}\ {M}_{\odot }$) and radius (${R}_{1}={8.37}_{-0.07}^{+0.03}\ {R}_{\odot }$, ${R}_{2}={8.30}_{-0.03}^{+0.04}\ {R}_{\odot }$), an asteroseismic analysis finds one Main set of solar-like oscillations with unusually low-amplitude, wide modes. A second set of oscillations from the other star may exist, but this marginal detection is extremely faint. Because the two stars are nearly twins, KIC 9246715 is a difficult target for a precise test of the asteroseismic scaling relations, which yield M = 2.17 ± 0.14 M⊙ and R = 8.26 ± 0.18 R⊙. Both stars are consistent with the inferred asteroseismic properties, but we suspect the Main Oscillator is Star 2 because it is less active than Star 1. We find evidence for stellar activity and modest tidal forces acting over the 171 day eccentric orbit, which are likely responsible for the essential lack of solar-like oscillations in one star and weak oscillations in the other. Mixed modes indicate the Main oscillating star is on the secondary red clump (a core-He-burning star), and stellar evolution modeling supports this with a coeval history for a pair of red clump stars. This system is a useful case study and paves the way for a detailed analysis of more red giants in eclipsing binaries, an important benchmark for asteroseismology
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KIC 9246715: The Double Red Giant Eclipsing Binary With Odd Oscillations
'American Astronomical Society', 2015Co-Authors: Rawls, Meredith L., Gaulme Patrick, Mckeever Jean, Jackiewicz Jason, Orosz, Jerome A., Corsaro Enrico, Latham, David W., Beck Paul, Mosser Benoît, Latham, Christian A.Abstract:We combine Kepler photometry with ground-based spectra to present a comprehensive dynamical model of the double red giant eclipsing binary KIC 9246715. While the two stars are very similar in mass (M1 = 2.171 [+0.006 / -0.008], M2 = 2.149 [+0.006 / -0.008] Msun) and radius (R1 = 8.37 [+0.03 / -0.07], R2 = 8.30 [+0.04 / -0.03] Rsun), an asteroseismic analysis finds one Main set of solar-like oscillations with unusually low-amplitude, wide modes. A second set of oscillations from the other star may exist, but this marginal detection is extremely faint. Because the two stars are nearly twins, KIC 9246715 is a difficult target for a precise test of the asteroseismic scaling relations, which yield M = 2.17 +/- 0.14 Msun and R = 8.26 +/- 0.18 Rsun. Both stars are consistent with the inferred asteroseismic properties, but we suspect the Main Oscillator is Star 2 because it is less active than Star 1. We find evidence for stellar activity and modest tidal forces acting over the 171-day eccentric orbit, which are likely responsible for the essential lack of solar-like oscillations in one star and weak oscillations in the other. Mixed modes indicate the Main oscillating star is on the secondary red clump (a core-He-burning star), and stellar evolution modeling supports this with a coeval history for a pair of red clump stars. This system is a useful case study and paves the way for a detailed analysis of more red giants in eclipsing binaries, an important benchmark for asteroseismology.Comment: 20 pages, 12 figures, 4 tables; accepted for publication in The Astrophysical Journa
