Prenatal Inflammation Reprograms Hypothalamic-Pituitary-Gonadal Axis Development in Female Rats

Area of Science:

• Neuroendocrinology
• Developmental Biology
• Immunology

Background:

• Maternal immune activation during pregnancy can disrupt fetal development.
• Bacterial lipopolysaccharide (LPS) induces inflammation and cytokine release, potentially affecting the hypothalamic-pituitary-gonadal (HPG) axis.
• Epigenetic changes may mediate long-term effects of prenatal inflammation on fertility.

Purpose of the Study:

• To investigate the long-term consequences of prenatal LPS exposure on HPG axis development in female rats.
• To evaluate the efficacy of anti-inflammatory treatments (polyclonal IgG and anti-IL-6 receptor antibodies) in mitigating LPS-induced effects.

Main Methods:

• Pregnant rats were exposed to LPS on embryonic day 12.
• Offspring were assessed as adults for HPG axis parameters, including hypothalamic neuronal connections, ovarian morphology, and steroidogenesis.
• Specific treatments were administered post-LPS exposure to assess their protective effects.

Main Results:

• Prenatal LPS exposure resulted in reduced synaptic inputs to GnRH neurons, increased follicular atresia, and suppressed ovarian steroidogenesis in adult female offspring.
• Treatment with polyclonal IgG or IL-6 receptor blockade prevented these adverse long-term effects.
• These findings implicate IL-6 in the developmental disruption caused by prenatal inflammation.

Conclusions:

• Prenatal exposure to LPS negatively impacts HPG axis development and reproductive function in female rats.
• Targeting IL-6 signaling, possibly through anti-inflammatory interventions, can prevent these detrimental effects.
• IL-6 plays a crucial role in the neuroendocrine programming of the HPG axis during development.