Rozenblit-Susan Sigal, Chapnik Nava, Genzer Yoni, Froy Oren
Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
Institute of Biochemistry, Food Science and Nutrition, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
Behav Brain Res. 2016 Jan 15;297:150-4. doi: 10.1016/j.bbr.2015.10.019. Epub 2015 Oct 20.
The serotonergic and circadian systems are intertwined as serotonin modulates the response of the central brain suprachiasmatic nuclei (SCN) clock to light. Time-restricted feeding (RF) is characterized by increased food anticipatory activity (FAA) and controlled by the food-entrainable oscillator (FEO) rather than the SCN. Our objective was to test whether serotonin affects the FEO. Mice were treated with the selective serotonin reuptake inhibitor (SSRI) fluvoxamine (FLX) or the tryptophan hydroxylase inhibitor parachlorophenylalanine (PCPA) and locomotor activity under ad libitum feeding, RF and different lighting conditions was monitored. Under AL, FLX administration did not affect 24-h locomotor activity, while mice treated with PCPA exhibited increased activity. RF-FLX-treated mice showed less FAA 2h before food availability (ZT2-ZT4) compared to RF- or RF-PCPA-fed mice. Under DD, RF-PCPA-treated mice displayed increased activity, as was seen under LD conditions. Surprisingly, RF-PCPA-treated mice showed free running in the FAA component. These results emphasize the role of serotonin in SCN-mediated activity inhibition and FEO entrainment and activity.
血清素能系统和昼夜节律系统相互交织，因为血清素调节中枢脑视交叉上核（SCN）时钟对光的反应。限时进食（RF）的特征是食物预期活动（FAA）增加，且由食物可调节振荡器（FEO）而非SCN控制。我们的目的是测试血清素是否影响FEO。给小鼠注射选择性血清素再摄取抑制剂（SSRI）氟伏沙明（FLX）或色氨酸羟化酶抑制剂对氯苯丙氨酸（PCPA），并在自由进食、RF和不同光照条件下监测其运动活动。在自由进食（AL）条件下，给予FLX不影响24小时运动活动，而用PCPA处理的小鼠活动增加。与RF或RF-PCPA喂养的小鼠相比，RF-FLX处理的小鼠在食物可得前2小时（ZT2-ZT4）表现出较少的FAA。在持续黑暗（DD）条件下，RF-PCPA处理的小鼠活动增加，这与在光照/黑暗（LD）条件下观察到的情况相同。令人惊讶的是，RF-PCPA处理的小鼠在FAA成分中表现出自由运行。这些结果强调了血清素在SCN介导的活动抑制和FEO同步化及活动中的作用。
