Development and Entrainment of the Fetal Clock in the Suprachiasmatic Nuclei: The Role of Glucocorticoids

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985823%3A_____%2F19%3A00506579" target="_blank" >RIV/67985823:_____/19:00506579 - isvavai.cz</a>

Výsledek na webu

<a href="https://journals.sagepub.com/doi/10.1177/0748730419835360" target="_blank" >https://journals.sagepub.com/doi/10.1177/0748730419835360</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1177/0748730419835360" target="_blank" >10.1177/0748730419835360</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Development and Entrainment of the Fetal Clock in the Suprachiasmatic Nuclei: The Role of Glucocorticoids

Popis výsledku v původním jazyce

The adult circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus is resilient to glucocorticoids (GCs). The fetal rodent SCN resembles that of the adult in its organization of GC-sensitive peripheral tissues. We tested the hypothesis that the fetal SCN clock is sensitive to changes in GC levels. Maternal GCs must pass through the placenta to reach the fetal SCN. We show that the maternal but not the fetal part of the placenta harbors the autonomous circadian clock, which is reset by dexamethasone (DEX) and rhythmically expresses Hsd11b2. The results suggest the presence of a mechanism for rhythmic GC passage through the placental barrier, which is adjusted according to actual GC levels. GC receptors are expressed rhythmically in the laser-dissected fetal SCN samples. We demonstrate that hypothalamic explants containing the SCN of the mPer2(Luc) mouse prepared at embryonic day (E)15 spontaneously develop rhythmicity within several days of culture, with dynamics varying among fetuses from the same litter. Culturing these explants in media enriched with DEX accelerates the development. At E17, treatment of the explants with DEX induces phase advances and phase delays of the rhythms depending on the timing of treatments, and the shifts are completely blocked by the GC receptor antagonist, mifepristone. The DEX-induced phase-response curve differs from that induced by the vehicle. The fetal SCN is sensitive to GCs in vivo because DEX administration to pregnant rats acutely downregulates c-fos expression specifically in the laser-dissected fetal SCN. Our results provide evidence that the rodent fetal SCN clock may respond to changes in GC levels.

Název v anglickém jazyce

Development and Entrainment of the Fetal Clock in the Suprachiasmatic Nuclei: The Role of Glucocorticoids

Popis výsledku anglicky

The adult circadian clock in the suprachiasmatic nucleus (SCN) of the hypothalamus is resilient to glucocorticoids (GCs). The fetal rodent SCN resembles that of the adult in its organization of GC-sensitive peripheral tissues. We tested the hypothesis that the fetal SCN clock is sensitive to changes in GC levels. Maternal GCs must pass through the placenta to reach the fetal SCN. We show that the maternal but not the fetal part of the placenta harbors the autonomous circadian clock, which is reset by dexamethasone (DEX) and rhythmically expresses Hsd11b2. The results suggest the presence of a mechanism for rhythmic GC passage through the placental barrier, which is adjusted according to actual GC levels. GC receptors are expressed rhythmically in the laser-dissected fetal SCN samples. We demonstrate that hypothalamic explants containing the SCN of the mPer2(Luc) mouse prepared at embryonic day (E)15 spontaneously develop rhythmicity within several days of culture, with dynamics varying among fetuses from the same litter. Culturing these explants in media enriched with DEX accelerates the development. At E17, treatment of the explants with DEX induces phase advances and phase delays of the rhythms depending on the timing of treatments, and the shifts are completely blocked by the GC receptor antagonist, mifepristone. The DEX-induced phase-response curve differs from that induced by the vehicle. The fetal SCN is sensitive to GCs in vivo because DEX administration to pregnant rats acutely downregulates c-fos expression specifically in the laser-dissected fetal SCN. Our results provide evidence that the rodent fetal SCN clock may respond to changes in GC levels.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

30105 - Physiology (including cytology)

Projekt

<a href="/cs/project/GA16-03932S" target="_blank" >GA16-03932S: Mechanismy mateřské synchronizace fetálních cirkadiánních hodin savců</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Biological Rhythms

ISSN

0748-7304

e-ISSN

—

Svazek periodika

34

Číslo periodika v rámci svazku

3

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

307-322

Kód UT WoS článku

000473506900007

EID výsledku v databázi Scopus

2-s2.0-85062854977