INS NYC 2024 Program

Poster	Poster Session 08 Program Schedule 02/16/2024 01:45 pm - 03:00 pm Room: Shubert Complex (Posters 1-60) Poster Session 08: Cognition \| Cognitive Reserve Variables Final Abstract #44 Exploring the Interplay Between Sleep Patterns, Hormones, and Cortisol: Insights from Mice and Human Studies Tommy Li, IYRC, New York, United States Paul Lewis, IYRC, New York, United States Category: Sleep and Sleep Disorders Keyword 1: sleep Keyword 2: hormones Keyword 3: sleep disorders Objective: What is the relationship between sleeping patterns and hormones, such as cortisol? Participants and Methods: In order to test for all these aspects, there would need to be multiple tests, one concerning just sleeping patterns, one concerning a diet that affects the hormones, and one concerning hormones. Mice were housed at a maximum of five mice per cage with food and water and maintained in the same conditions. All mice were injected with AAV-GCaMP6s, a calcium sensor, to track calcium activities during sleep. Regarding the diets, participants consumed control cereals providing 22.5 mg of tryptophan per 30 g, twice per day, as part of their usual diet, followed by 1 week of consuming 2 daily servings of 30 g of cereals enriched with 60 mg/serving of tryptophan and a final week in which participants returned to their habitual diet. To test for hormones, in this case, cortisol, participants ((N=17 [3 females]) aged 31.7 ± 6.1) were tested individually in an environment free of time cues. Conditions such as light, temperature, sleep-wake opportunities, and diet were all the same. Participants were initially subjected to 16 hours of wakefulness and 8 hours of sleep for six days. After that, a routine for days 7-8 was used to examine cortisol levels after 40 hours of sleep deprivation. Results: Activity in LPO neurons is highest during REM sleep. The mice were injected in LPO and the highest calcium activity occurred during REM sleep episodes. During NREM, LPO neurons showed a more irregular activity, with calcium activity generally low. Calcium entry through NMDA receptors is an essential part of sleep homeostasis, tracking the time spent awake, showing that at high calcium levels, the time asleep was being tracked. Regarding the cereal study, consumption of a high-tryptophan cereal for 1 week increased sleep duration, and efficiency, and reduced sleep onset latency. Excretion of melatonin and serotonin was significantly increased after 1 week of consumption of the high-tryptophan cereal, attributing to increases in both melatonin and serotonin synthesis following increased tryptophan consumption. The increase in hormones such as melatonin and serotonin increases sleep efficiency. Cortisol concentrations decrease rapidly in the first 20 minutes after SWS onset, and there is a consistent inverse temporal relationship between low cortisol concentrations and high SWS. However, after following sleep deprivation, cortisol levels increase, increasing sleep pressure. Conclusions: Regions such as the hypothalamus directly affect sleep, controlling the sleep-wake cycle. Neurons such as LPO neurons in the hypothalamus use calcium from NMDA receptors as a way to control the sleep-wake cycle. However, sleep is not only a neurological process, with many hormones controlling it as well. The most notable are melatonin and serotonin, which can be increased from a high Tryptophan diet. Tryptophan is also linked to significantly lower cortisol response to stress. With a low cortisol level, people fall into SWS (slow-wave sleep) more easily.

Poster

Poster Session 08 Program Schedule

02/16/2024
01:45 pm - 03:00 pm
Room: Shubert Complex (Posters 1-60)

Poster Session 08: Cognition | Cognitive Reserve Variables

Final Abstract #44

Exploring the Interplay Between Sleep Patterns, Hormones, and Cortisol: Insights from Mice and Human Studies

Tommy Li, IYRC, New York, United States
Paul Lewis, IYRC, New York, United States

Category: Sleep and Sleep Disorders

Keyword 1: sleep
Keyword 2: hormones
Keyword 3: sleep disorders

Objective:

What is the relationship between sleeping patterns and hormones, such as cortisol?

Participants and Methods:

In order to test for all these aspects, there would need to be multiple tests, one concerning just sleeping patterns, one concerning a diet that affects the hormones, and one concerning hormones. Mice were housed at a maximum of five mice per cage with food and water and maintained in the same conditions. All mice were injected with AAV-GCaMP6s, a calcium sensor, to track calcium activities during sleep. Regarding the diets, participants consumed control cereals providing 22.5 mg of tryptophan per 30 g, twice per day, as part of their usual diet, followed by 1 week of consuming 2 daily servings of 30 g of cereals enriched with 60 mg/serving of tryptophan and a final week in which participants returned to their habitual diet. To test for hormones, in this case, cortisol, participants ((N=17 [3 females]) aged 31.7 ± 6.1) were tested individually in an environment free of time cues. Conditions such as light, temperature, sleep-wake opportunities, and diet were all the same. Participants were initially subjected to 16 hours of wakefulness and 8 hours of sleep for six days. After that, a routine for days 7-8 was used to examine cortisol levels after 40 hours of sleep deprivation.

Results:

Activity in LPO neurons is highest during REM sleep. The mice were injected in LPO and the highest calcium activity occurred during REM sleep episodes. During NREM, LPO neurons showed a more irregular activity, with calcium activity generally low. Calcium entry through NMDA receptors is an essential part of sleep homeostasis, tracking the time spent awake, showing that at high calcium levels, the time asleep was being tracked.

Regarding the cereal study, consumption of a high-tryptophan cereal for 1 week increased sleep duration, and efficiency, and reduced sleep onset latency. Excretion of melatonin and serotonin was significantly increased after 1 week of consumption of the high-tryptophan cereal, attributing to increases in both melatonin and serotonin synthesis following increased tryptophan consumption. The increase in hormones such as melatonin and serotonin increases sleep efficiency.

Cortisol concentrations decrease rapidly in the first 20 minutes after SWS onset, and there is a consistent inverse temporal relationship between low cortisol concentrations and high SWS. However, after following sleep deprivation, cortisol levels increase, increasing sleep pressure.

Conclusions:

Regions such as the hypothalamus directly affect sleep, controlling the sleep-wake cycle. Neurons such as LPO neurons in the hypothalamus use calcium from NMDA receptors as a way to control the sleep-wake cycle. However, sleep is not only a neurological process, with many hormones controlling it as well. The most notable are melatonin and serotonin, which can be increased from a high Tryptophan diet. Tryptophan is also linked to significantly lower cortisol response to stress. With a low cortisol level, people fall into SWS (slow-wave sleep) more easily.