Limits...
A balanced diet is necessary for proper entrainment signals of the mouse liver clock.

Hirao A, Tahara Y, Kimura I, Shibata S - PLoS ONE (2009)

Bottom Line: When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein.Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment.These findings may assist in the development of dietary recommendations for on-board meals served to air travelers and shift workers to reduce jet lag-like symptoms.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan.

ABSTRACT

Background: The peripheral circadian clock in mice is entrained not only by light-dark cycles but also by daily restricted feeding schedules. Behavioral and cell culture experiments suggest an increase in glucose level as a factor in such feeding-induced entrainment. For application of feeding-induced entrainment in humans, nutrient content and dietary variations should be considered.

Principal finding: To elucidate the food composition necessary for dietary entrainment, we examined whether complete or partial substitution of dietary nutrients affected phase shifts in liver clocks of mice. Compared with fasting mice or ad libitum fed mice, the liver bioluminescence rhythm advanced by 3-4 h on the middle day in Per2::luciferase knock-in mice that were administered a standard mouse diet, i.e. AIN-93M formula [0.6-0.85 g/10 g mouse BW] (composition: 14% casein, 47% cornstarch, 15% gelatinized cornstarch, 10% sugar, 4% soybean oil, and 10% other [fiber, vitamins, minerals, etc.]), for 2 days. When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein. A combination of glucose and casein without oil, vitamin, or fiber caused a significant phase advance. When cornstarch in AIN-93M was substituted with glucose, sucrose, fructose, polydextrose, high-amylose cornstarch, or gelatinized cornstarch, the amplitude of phase advance paralleled the increase in blood glucose concentration.

Conclusions: Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment. These findings may assist in the development of dietary recommendations for on-board meals served to air travelers and shift workers to reduce jet lag-like symptoms.

Show MeSH
Effects of the substitution of cornstarch in AIN-93M by gelatinized cornstarch (GCS) or high-amylose cornstarch (HACS) on the phase of the liver circadian clock and relative blood glucose value.A: Percent component of each nutrient in AIN-93M. Substituted components are shown by the white column segments. B: Mice were administered a diet tablet containing 0.6 g/10 g BW of the substituted diet on the first day and 0.85 g/10 g BW of the substituted diet on the second day after 24-h food deprivation. The components of cornstarch and GCS in AIN-93M were replaced with GCS or HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting). #P<0.05 (vs. GCS). C: Time course of the blood glucose level after oral injection of 0.03 g/10 g BW of each substituted nutrient. The vertical axis indicates the content of glucose (mg/dL). The values indicate the mean±SEM. Symbol color of each treatment is same as column color in part D. D: Relative blood glucose value (% of glucose) of the nutrient-substituted group. Fisher's PLSD test. **P<0.01 (vs. water), ##P<0.01 (vs. GCS). The numbers in parentheses indicate the number of tested mice. E: Percent component of each nutrient in AIN-93M. Substituted components are shown by white column segments. F: All nutrient components in AIN-93M were completely substituted with 100% cornstarch, 100% GCS, or 100% HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting); fasting, 2-day fast # P<0.05, ## P<0.01 (vs. AIN-93M). The numbers in the parentheses indicate the number of tested mice. We used the same data of fasting or 100% cornstarch as mentioned in Fig. 2 to produce Fig. 4.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2734168&req=5

pone-0006909-g004: Effects of the substitution of cornstarch in AIN-93M by gelatinized cornstarch (GCS) or high-amylose cornstarch (HACS) on the phase of the liver circadian clock and relative blood glucose value.A: Percent component of each nutrient in AIN-93M. Substituted components are shown by the white column segments. B: Mice were administered a diet tablet containing 0.6 g/10 g BW of the substituted diet on the first day and 0.85 g/10 g BW of the substituted diet on the second day after 24-h food deprivation. The components of cornstarch and GCS in AIN-93M were replaced with GCS or HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting). #P<0.05 (vs. GCS). C: Time course of the blood glucose level after oral injection of 0.03 g/10 g BW of each substituted nutrient. The vertical axis indicates the content of glucose (mg/dL). The values indicate the mean±SEM. Symbol color of each treatment is same as column color in part D. D: Relative blood glucose value (% of glucose) of the nutrient-substituted group. Fisher's PLSD test. **P<0.01 (vs. water), ##P<0.01 (vs. GCS). The numbers in parentheses indicate the number of tested mice. E: Percent component of each nutrient in AIN-93M. Substituted components are shown by white column segments. F: All nutrient components in AIN-93M were completely substituted with 100% cornstarch, 100% GCS, or 100% HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting); fasting, 2-day fast # P<0.05, ## P<0.01 (vs. AIN-93M). The numbers in the parentheses indicate the number of tested mice. We used the same data of fasting or 100% cornstarch as mentioned in Fig. 2 to produce Fig. 4.

Mentions: There are two different kinds of cornstarch: HACS and low-amylose cornstarch. In the present experiment, we substituted the components of cornstarch and gelatinized cornstarch in the AIN-93M diet with GCS or HACS (Fig. 4A). Substitution with GCS produced a stronger phase advance as compared to HACS with regard to the percent of glucose value (Fig. 4B, P<0.05, Fisher's PLSD test). As expected, the increase in blood glucose was faster and higher in the GCS group than in the HACS group (Fig. 4C and D). In order to confirm that 100% cornstarch caused a weak phase advance of the liver clock (Fig. 2B), we examined the effect of 100% GCS or 100% HACS on phase shift (Fig. 4E). Neither 100% GCS nor 100% HACS caused a phase advance of the liver clock (P>0.05 vs. fasting) (Fig. 4F). Thus, there were significant differences between the effects of AIN-93M containing cornstarch, GCS, or HACS (P<0.05, 0.01).


A balanced diet is necessary for proper entrainment signals of the mouse liver clock.

Hirao A, Tahara Y, Kimura I, Shibata S - PLoS ONE (2009)

Effects of the substitution of cornstarch in AIN-93M by gelatinized cornstarch (GCS) or high-amylose cornstarch (HACS) on the phase of the liver circadian clock and relative blood glucose value.A: Percent component of each nutrient in AIN-93M. Substituted components are shown by the white column segments. B: Mice were administered a diet tablet containing 0.6 g/10 g BW of the substituted diet on the first day and 0.85 g/10 g BW of the substituted diet on the second day after 24-h food deprivation. The components of cornstarch and GCS in AIN-93M were replaced with GCS or HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting). #P<0.05 (vs. GCS). C: Time course of the blood glucose level after oral injection of 0.03 g/10 g BW of each substituted nutrient. The vertical axis indicates the content of glucose (mg/dL). The values indicate the mean±SEM. Symbol color of each treatment is same as column color in part D. D: Relative blood glucose value (% of glucose) of the nutrient-substituted group. Fisher's PLSD test. **P<0.01 (vs. water), ##P<0.01 (vs. GCS). The numbers in parentheses indicate the number of tested mice. E: Percent component of each nutrient in AIN-93M. Substituted components are shown by white column segments. F: All nutrient components in AIN-93M were completely substituted with 100% cornstarch, 100% GCS, or 100% HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting); fasting, 2-day fast # P<0.05, ## P<0.01 (vs. AIN-93M). The numbers in the parentheses indicate the number of tested mice. We used the same data of fasting or 100% cornstarch as mentioned in Fig. 2 to produce Fig. 4.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2734168&req=5

pone-0006909-g004: Effects of the substitution of cornstarch in AIN-93M by gelatinized cornstarch (GCS) or high-amylose cornstarch (HACS) on the phase of the liver circadian clock and relative blood glucose value.A: Percent component of each nutrient in AIN-93M. Substituted components are shown by the white column segments. B: Mice were administered a diet tablet containing 0.6 g/10 g BW of the substituted diet on the first day and 0.85 g/10 g BW of the substituted diet on the second day after 24-h food deprivation. The components of cornstarch and GCS in AIN-93M were replaced with GCS or HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting). #P<0.05 (vs. GCS). C: Time course of the blood glucose level after oral injection of 0.03 g/10 g BW of each substituted nutrient. The vertical axis indicates the content of glucose (mg/dL). The values indicate the mean±SEM. Symbol color of each treatment is same as column color in part D. D: Relative blood glucose value (% of glucose) of the nutrient-substituted group. Fisher's PLSD test. **P<0.01 (vs. water), ##P<0.01 (vs. GCS). The numbers in parentheses indicate the number of tested mice. E: Percent component of each nutrient in AIN-93M. Substituted components are shown by white column segments. F: All nutrient components in AIN-93M were completely substituted with 100% cornstarch, 100% GCS, or 100% HACS. The horizontal axis indicates the pZT at the peak of the bioluminescence rhythm. Fisher's PLSD test. *P<0.05 (vs. fasting); fasting, 2-day fast # P<0.05, ## P<0.01 (vs. AIN-93M). The numbers in the parentheses indicate the number of tested mice. We used the same data of fasting or 100% cornstarch as mentioned in Fig. 2 to produce Fig. 4.
Mentions: There are two different kinds of cornstarch: HACS and low-amylose cornstarch. In the present experiment, we substituted the components of cornstarch and gelatinized cornstarch in the AIN-93M diet with GCS or HACS (Fig. 4A). Substitution with GCS produced a stronger phase advance as compared to HACS with regard to the percent of glucose value (Fig. 4B, P<0.05, Fisher's PLSD test). As expected, the increase in blood glucose was faster and higher in the GCS group than in the HACS group (Fig. 4C and D). In order to confirm that 100% cornstarch caused a weak phase advance of the liver clock (Fig. 2B), we examined the effect of 100% GCS or 100% HACS on phase shift (Fig. 4E). Neither 100% GCS nor 100% HACS caused a phase advance of the liver clock (P>0.05 vs. fasting) (Fig. 4F). Thus, there were significant differences between the effects of AIN-93M containing cornstarch, GCS, or HACS (P<0.05, 0.01).

Bottom Line: When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein.Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment.These findings may assist in the development of dietary recommendations for on-board meals served to air travelers and shift workers to reduce jet lag-like symptoms.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Shinjuku-ku, Tokyo, Japan.

ABSTRACT

Background: The peripheral circadian clock in mice is entrained not only by light-dark cycles but also by daily restricted feeding schedules. Behavioral and cell culture experiments suggest an increase in glucose level as a factor in such feeding-induced entrainment. For application of feeding-induced entrainment in humans, nutrient content and dietary variations should be considered.

Principal finding: To elucidate the food composition necessary for dietary entrainment, we examined whether complete or partial substitution of dietary nutrients affected phase shifts in liver clocks of mice. Compared with fasting mice or ad libitum fed mice, the liver bioluminescence rhythm advanced by 3-4 h on the middle day in Per2::luciferase knock-in mice that were administered a standard mouse diet, i.e. AIN-93M formula [0.6-0.85 g/10 g mouse BW] (composition: 14% casein, 47% cornstarch, 15% gelatinized cornstarch, 10% sugar, 4% soybean oil, and 10% other [fiber, vitamins, minerals, etc.]), for 2 days. When each nutrient was tested alone (100% nutrient), an insignificant weak phase advance was found to be induced by cornstarch and soybean oil, but almost no phase advance was induced by gelatinized cornstarch, high-amylose cornstarch, glucose, sucrose, or casein. A combination of glucose and casein without oil, vitamin, or fiber caused a significant phase advance. When cornstarch in AIN-93M was substituted with glucose, sucrose, fructose, polydextrose, high-amylose cornstarch, or gelatinized cornstarch, the amplitude of phase advance paralleled the increase in blood glucose concentration.

Conclusions: Our results strongly suggest the following: (1) balanced diets containing carbohydrates/sugars and proteins are good for restricted feeding-induced entrainment of the peripheral circadian clock and (2) a balanced diet that increases blood glucose, but not by sugar alone, is suitable for entrainment. These findings may assist in the development of dietary recommendations for on-board meals served to air travelers and shift workers to reduce jet lag-like symptoms.

Show MeSH