視網膜神經可影響食物攝入信號
作者:
小柯機器人發布時間:2020/4/23 14:26:19
美國國立衛生研究院Samer Hattar、Diego Carlos Fernandez等研究人員合作發現,視網膜神經可影響食物攝入信號。這一研究成果於2020年4月22日在線發表在《自然》上。
研究人員測試了視網膜輸入是否調節了對非光信號的傳輸,例如限時餵養。通過固有的光敏性視網膜神經節細胞(ipRGCs),光信息傳遞到視交叉上核(SCN)–中央晝夜節律起搏器–以及脈間小葉(IGL)。
研究人員發現,從出生後早期階段缺乏ipRGCs的成年小鼠對限時進食的傳輸能力受損,而在後期階段ipRGCs的敲除則沒有效果。產後早期的ipRGC神經分布會影響表達神經肽Y(NPY)的IGL神經元(以下簡稱IGLNPY神經元),並指導功能性IGLNPY-SCN迴路的構建。
此外,在成年小鼠中使IGLNPY神經元沉默可模仿出生後早期ipRGC敲除產生的缺陷,而SCN中IGLNPY末端的急性抑制降低了食物預期活力。因此,在產後早期對ipRGCs的神經分布可以調節IGLNPY-SCN迴路,從而可以影響限時進食。
據介紹,光照和食物供應量的每日變化是影響晝夜節律的主要時間線索。然而,對於將這些時間信息如何整合從而影響晝夜節律的迴路知之甚少。
附:英文原文
Title: Retinal innervation tunes circuits that drive nonphotic entrainment to food
Author: Diego Carlos Fernandez, Ruchi Komal, Jennifer Langel, Jun Ma, Phan Q. Duy, Mario A. Penzo, Haiqing Zhao, Samer Hattar
Issue&Volume: 2020-04-22
Abstract: Daily changes in light and food availability are major time cues that influence circadian timing1. However, little is known about the circuits that integrate these time cues to drive a coherent circadian output1,2,3. Here we investigate whether retinal inputs modulate entrainment to nonphotic cues such as time-restricted feeding. Photic information is relayed to the suprachiasmatic nucleus (SCN)—the central circadian pacemaker—and the intergeniculate leaflet (IGL) through intrinsically photosensitive retinal ganglion cells (ipRGCs)4. We show that adult mice that lack ipRGCs from the early postnatal stages have impaired entrainment to time-restricted feeding, whereas ablation of ipRGCs at later stages had no effect. Innervation of ipRGCs at early postnatal stages influences IGL neurons that express neuropeptide Y (NPY) (hereafter, IGLNPY neurons), guiding the assembly of a functional IGLNPY–SCN circuit. Moreover, silencing IGLNPY neurons in adult mice mimicked the deficits that were induced by ablation of ipRGCs in the early postnatal stages, and acute inhibition of IGLNPY terminals in the SCN decreased food-anticipatory activity. Thus, innervation of ipRGCs in the early postnatal period tunes the IGLNPY–SCN circuit to allow entrainment to time-restricted feeding.
DOI: 10.1038/s41586-020-2204-1
Source: https://www.nature.com/articles/s41586-020-2204-1