Maternal dexamethasone exposure inhibits the gonadotropin-releasing hormone neuronal movement in the preoptic area of rat offspring.

Dev Neurosci

Brain Research Institute, School of Medicine and Health Sciences, Monash University Malaysia, Petaling Jaya, Selangor, Malaysia.

Published: February 2015

Migration and final positioning of gonadotropin-releasing hormone (GnRH) neurons in the preoptic area (POA) is critical for reproduction. It is known that maternal dexamethasone (DEX) exposure impairs reproductive function and behaviour in the offspring. However, it is still not known whether maternal DEX exposure affects the postnatal GnRH neurons in the offspring. This study determined the neuronal movement of enhanced green fluorescent protein (EGFP)-tagged GnRH neurons in slice culture of postnatal day 0 (P0), P5 and P50-60 transgenic male rats. Effect of maternal DEX treatment on EGFP-GnRH neuronal movement and F-actin distribution on GnRH neurons at P0 stage were studied. Time-lapse analysis of P0 and P5 EGFP-GnRH neurons displayed active cellular movement within the POA compared to young adult P50-60 stages, suggesting possible fine-tuning movement for positioning of early postnatal GnRH neurons. The DEX-treated EGFP-GnRH neurons demonstrated decreased motility in the POA and reduced F-actin distribution in the GnRH neurons at 60 h culture compared to the vehicle-treated. These results suggest that the P0 GnRH neuronal movement in the POA is altered by maternal DEX exposure, which possibly disrupts the fine-tuning process for positioning and development of early postnatal GnRH neurons in the brain, potentially linked to reproductive dysfunction in adulthood.

Download full-text PDF

Source
http://dx.doi.org/10.1159/000360416DOI Listing

Publication Analysis

Top Keywords

gnrh neurons
28
neuronal movement
16
dex exposure
12
maternal dex
12
postnatal gnrh
12
neurons
9
maternal dexamethasone
8
gonadotropin-releasing hormone
8
preoptic area
8
gnrh
8

Similar Publications

Kisspeptin and Neurokinin B: roles in reproductive health.

Physiol Rev

January 2025

Department of Investigative Medicine, Imperial College London, Hammersmith Hospital, London, United Kingdom.

Kisspeptin and neurokinin B (NKB) play a key role in several physiological processes including in puberty, adult reproductive function including the menstrual cycle, as well as mediating the symptoms of menopause. Infundibular kisspeptin neurons, which co-express NKB, regulate the activity of gonadotropin releasing hormone (GnRH) neurons, and thus the physiological pulsatile secretion of GnRH from the hypothalamus. Outside of their hypothalamic reproductive roles, these peptides are implicated in several physiological functions including sexual behavior and attraction, placental function, and bone health.

View Article and Find Full Text PDF

Multi-dimensional oscillatory activity of mouse GnRH neurons in vivo.

Elife

January 2025

Department of Physiology, Development and Neuroscience, Downing site, University of Cambridge, Cambridge, United Kingdom.

The gonadotropin-releasing hormone (GnRH) neurons represent the key output cells of the neural network controlling mammalian fertility. We used GCaMP fiber photometry to record the population activity of the GnRH neuron distal projections in the ventral arcuate nucleus where they merge before entering the median eminence to release GnRH into the portal vasculature. Recordings in freely behaving intact male and female mice revealed abrupt ~8 min duration increases in activity that correlated perfectly with the appearance of a subsequent pulse of luteinizing hormone (LH).

View Article and Find Full Text PDF

GnRH pulse generator activity in mouse models of polycystic ovary syndrome.

Elife

January 2025

Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom.

Article Synopsis
  • One in ten women of reproductive age have PCOS, characterized by subfertility, high LH levels, and potential dysfunction in the kisspeptin neurons that regulate GnRH.
  • Researchers studied the GnRH pulse generator in two mouse models of PCOS: the peripubertal androgen (PPA) model showed fewer synchronized neuron events, while the prenatal androgen (PNA) model revealed variable GnRH activity but cyclical patterns indicating complexity.
  • Findings indicate that in the PNA model, ARN neurons had increased activity during specific stages and less sensitivity to progesterone, highlighting the need to understand GnRH regulation in PCOS-related conditions.
View Article and Find Full Text PDF

While hypothalamic kisspeptin (KP) neurons play well-established roles in the estrogen-dependent regulation of reproduction, little is known about extrahypothalamic KP-producing (KP) neurons of the lateral septum. As established previously, expression in this region is low and regulated by estrogen receptor- and GABA receptor-dependent mechanisms. Our present experiments on knock-in mice revealed that transgene expression in the LS begins at P33-36 in females and P40-45 in males and is stimulated by estrogen receptor signaling.

View Article and Find Full Text PDF

Hypothalamic SIRT1-mediated regulation of the hormonal trigger of ovulation and its repression in energy deficit.

Metabolism

December 2024

Instituto Maimónides de Investigación Biomédica de Cordoba (IMIBIC), Department of Cell Biology, Physiology and Immunology, University of Cordoba; and Hospital Universitario Reina Sofia, Cordoba, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, Instituto de Salud Carlos III, Madrid, Spain. Electronic address:

Female reproduction is highly sensitive to body energy stores; persistent energy deficit, as seen in anorexia or strenuous exercise, is known to suppress ovulation via ill-defined mechanisms. We report herein that hypothalamic SIRT1, a key component of the epigenetic machinery that links nutritional status and puberty onset via modulation of Kiss1, plays a critical role in the control of the preovulatory surge of gonadotropins, i.e.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!