Administration of ghrelin associated with decreased expression of matrix metalloproteinase-9 following normobaric systemic hypoxia in the brain.

Objective: According to our previous studies, ghrelin protects blood brain barrier (BBB) integrity and it attenuates hypoxia-induced brain edema in the hypoxic conditions. However, the underlying mechanisms remain poorly understood. Several studies suggest a role for matrix metal-loproteinase-9 (MMP9) in the BBB disruption and cerebral edema formation.

Ghrelin ameliorates blood-brain barrier disruption during systemic hypoxia.

What is the central question of this study? Is an anti-oedematous effect of ghrelin associated with increased expression of tight junction proteins in the hypoxic brain? What is the main finding and its importance? We showed that injection of ghrelin during acute and chronic systemic hypoxia is associated with increased expression of tight junction proteins and protection of the blood-brain barrier. Ghrelin appears to be a new therapeutic strategy for protection of the blood-brain barrier from disruption and prevention of brain oedema in hypoxic conditions. The blood-brain barrier, which serves to protect the homeostasis of the CNS, is formed by tight junction proteins.

The Anti-Edematous Effect of Ghrelin in Brain Hypoxia is Associated with Decreasing Expression of Vascular Endothelial Growth Factor.

There is increasing evidence that vascular endothelial growth factor (VEGF) has a role in the development of vascular leakage in the hypoxic brain. Our recent work showed an anti-edematous effect of ghrelin on brain hypoxia. However, the underlying mechanisms by which ghrelin exerts its anti-edematous effect are still unclear.

Effect of ghrelin on brain edema induced by acute and chronic systemic hypoxia.

Hypoxia is an important pathogenic factor for the induction of vascular leakage and brain edema formation. Recent studies suggest a role for TNF-α in the induction of brain edema. Ghrelin attenuates the synthesis of TNF-α following subarachnoid hemorrhage and traumatic brain injury (TBI).