Circadian Regulation of Peripheral Serotonin in Mice
| dc.contributor.author | Karaganis, Stephen | |
| dc.contributor.author | Karaganis, Stephen | |
| dc.date.accessioned | 2023-02-27T20:18:32Z | |
| dc.date.available | 2023-02-27T20:18:32Z | |
| dc.date.issued | 2023-03-02 | |
| dc.description | C57BL/6 mice were fed ad libitum (AL) or placed on a gradual daytime restricted feeding regimen (DRF) while maintained in a 12:12 light-dark cycle (LD) or constant darkness (DD). Tissue samples were collected every fours in LD or DD conditions, beginning at ZT 2. Serotonin levels in tissues were quantified using ELISA (blood serum) or LC/MS/MS (duodenum and stools). Tph1 gene expression was measured using qPCR. Statistical analysis was performed using cosinor analysis (CircWave). | en_US |
| dc.description.abstract | Most organisms possess biological clocks which control and coordinate numerous physiological processes over each 24-hour day. Circadian oscillators play a role in generating biological rhythms and coordinating numerous processes with environmental stimuli, such as timing of a meal or exposure to light. The indolamine molecule serotonin is an important peripheral hormone produced by the intestinal mucosa of mammals, but its regulation as an output of the circadian clock is not well understood. Recent studies in my lab have investigated circadian rhythmicity of serotonin and its entrainment to light stimuli or food availability in various tissues or compartments in mice, including blood serum, stools, and the intestinal wall. In these experiments, mice were fed ad libitum (AL) or placed on a gradual daytime restricted feeding regimen (DRF) while maintained in a 12:12 light-dark cycle (LD) or constant darkness (DD). Using a repeated measures design, we demonstrated a high-amplitude circadian rhythm of serotonin in stool samples that persisted in constant conditions and entrained to both light and food availability, with a peak occurring close to the day-night transition under LD conditions. In contrast to some published findings, no circadian rhythm of serotonin was detected in blood serum. Preliminary data suggest that duodenal serotonin is rhythmic in LD and peaks later during the late night. This is consistent with our measurements of tph1 mRNA rhythms, which peaked during the late night in LD or DD, respectively. Taken together, these data suggest that peripheral serotonin is differentially regulated by the circadian clock in different compartments, and the rhythm of serotonin in stools is likely contributed to by oscillators outside the duodenum. | en_US |
| dc.identifier.uri | https://hdl.handle.net/11310/5062 | |
| dc.language.iso | en_US | en_US |
| dc.subject | 2023 Faculty and Student Research Poster Session and Research Fair | en_US |
| dc.subject | West Texas A&M University | en_US |
| dc.subject | Department of Life, Earth and Environmental Sciences | en_US |
| dc.subject | Poster | en_US |
| dc.subject | Circadian oscillators | en_US |
| dc.subject | Biological rhythms | en_US |
| dc.subject | Serotonin | en_US |
| dc.subject | Circadian clock | en_US |
| dc.title | Circadian Regulation of Peripheral Serotonin in Mice | en_US |
| dc.type | Presentation | en_US |