Long-term wheel-running and acute 6-h advances alter glucose tolerance and insulin levels in TALLYHO/JngJ mice

Abstract

Studies have shown a relationship between circadian rhythm disruptions and type-2 diabetes. This investigation examined the effects of circadian disruption (6-h phase advances) on the progression of diabetes in a type-2 diabetic mouse model -TALLYHO/JngJ - and whether wheel-running can alleviate the effects of the phase advances. 6-h advances alter fasting glucose, glucose tolerance and insulin production. Wheel-running reduced body mass, improved glucose tolerance and reduced insulin in TALLYHO/JngJ and alleviated some of the changes in diabetic symptoms due to 6-h advances. These results indicate that individuals with type-2 diabetes can benefit from physical activity and exercise can be a countermeasure to offset the effects of an acute phase advance.

The behavioral and physiological effects of high‐fat diet and alcohol consumption: Sex differences in C57BL6/J mice

“…Home‐cage locomotor activity was continuously recorded by IR beams located on the middle of each cage, above the cage lid (Starr Life Sciences, Oakmont, PA, USA) through the number of beam breaks. Total average locomotor activity, using Actiview (Starr Life Sciences) and a bout analysis ClockLab (Actimetrics, Wilmette, IL, USA), was calculated as previously described (Nascimento, Hicks, Carlson, Hatzidis, Amaral, Logan, et al., ; Nascimento, Hicks, Carlson, Hatzidis, Amaral, & Seggio, ) for both before (weeks 10–12) and after (weeks 13–15) the diet/drink switch.…”

Strain specific behavioral and physiological responses to constant light in male CBA/J and CBA/CaJ mice

“…This result may be the manifestation of baseline hyperglycemia and hyperinsulinemia within CBA/CaJ mice as found here (in LD elevated glucose and insulin compared to CBA/J) and elsewhere 34 . Another possibility is that the oscillations of glucose and insulin may be at different phases in LL compared to the behavioral rhythm, which may explain the lower glucose levels, as was seen in an example of a type 2 diabetic rodent model experiencing simulated jet-lag 13 . Previous work also illustrates that type 2 diabetes itself can affect the rhythmicity of insulin 35 and melatonin 36 , potentially leading to peripheral oscillators being at a different phase compared to behavioral rhythms.…”

“…Upon arrival, were housed individually and placed in a 12:12 h LD cycle (lights on 0600-1800H; lights off 1800-0600h, ceiling LED lights ~150 lux) with regular chow (LabDiet 5001, St. Louis, MO, USA) and water ad libitum . Circadian rhythms were measured using infrared home-cage sensors (StarrLife Sciences, Oakmount, PA, USA) as previously described 13 . After a one-week acclimation period, half of each substrain of mice were placed into constant light (LL) cycle while the other half remained in a LD cycle at room level lighting.…”