Platelet activating factor induces nerve growth factor production by rat astrocytes

Area of Science:

• Neuroscience
• Cell Biology
• Neuroinflammation

Background:

• Brain injury and inflammation trigger the release of neurotrophic factors.
• Platelet activating factor (PAF) is implicated in central nervous system pathologies.

Purpose of the Study:

• To investigate the effect of PAF on nerve growth factor (NGF) secretion by astrocytes.
• To determine if PAF plays a role in neurotrophic signaling following brain injury.

Main Methods:

• Primary rat cortical astrocyte cultures were treated with varying concentrations and durations of PAF.
• NGF secretion levels were measured.
• The effect of a specific PAF antagonist (WEB 2086) and co-treatment with tumor necrosis factor-alpha (TNF-alpha) were assessed.

Main Results:

• PAF induced a dose-dependent increase in NGF secretion, with a maximum 120% increase at 50 nM after 48 hours.
• The PAF-induced NGF secretion was blocked by the antagonist WEB 2086.
• PAF did not induce astrocyte proliferation.
• Concomitant treatment with PAF and TNF-alpha resulted in a synergistic increase in NGF secretion.

Conclusions:

• PAF acts as a potent stimulator of NGF secretion from astrocytes.
• PAF may contribute to neuroprotection by providing a neurotrophic signal to injured neurons.
• PAF cooperates with TNF-alpha in modulating neurotrophic factor release.