Effect of Leuprolide Acetate, a GnRH Agonist, on Neuroinflammation and Anxiety-Like Behavior after Mild Hypoxic-Ischemic Encephalopathy in Rat Model.

BACKGROUND

Mild hypoxic-ischemic encephalopathy (HIE) is a condition that predisposes to negative outcomes such as neuroanatomical injury, mood disorders, and motor or cognitive disabilities. The neuroinflammation plays an important role in the neurological damage; therefore, reducing it could provide neuroprotection. The leuprolide acetate (LA) has shown to have neuroregenerative and immunomodulator properties in other nervous system injuries.

OBJECTIVE

The aim of this study was to evaluate the immunomodulatory effect of LA in the acute phase of mild HIE and its effects in motor activity and behavior in a subacute phase.

METHOD: Forty-five Wistar rats on postnatal day 7 were divided into Sham, HIE treated with saline solution (HIE-SS), and HIE-LA. The HIE was performed cutting of the right carotid artery followed by 60 min of hypoxia. The expression of the inflammatory cytokines interleukin (IL)-1β, tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and the chemokine CXCL-1 were evaluated 72 h after HIE by RT-qPCR and the motor activity and behavior were evaluated by open field test at postnatal day 33.

RESULTS

HIE-SS animals showed increased expression of IL-1β, TNF-α, IFN-γ, and CXCL-1 genes in injured tissue. However, the HIE-LA group exhibited similar expression levels of IL-1β and TNF-α to the Sham group, while IFN-γ and CXCL-1 mRNA expression were attenuated with LA treatment. LA treatment also prevented anxiety-like behavior in the open field test.

CONCLUSION

Treatment with LA partially reverses HIE-induced neuroinflammation and prevents anxiety-like behavior in neonatal rats.