Chronic activation of microglial cells endangers neuronal survival through the release of various proinflammatory and neurotoxic factors. The root of Paeonia lactiflora Pall has been considered useful for the treatment of various disorders in
traditional oriental medicine.
Paeonol, found in the root of Paeonia lactiflora Pall, has a wide range of pharmacological functions, including anti-oxidative, anti-inflammatory and neuroprotective activities. The objective of this study was to examine the efficacy of
paeonol in the repression of
inflammation-induced neurotoxicity and microglial cell activation. Organotypic hippocampal slice cultures and primary microglial cells from rat brain were stimulated with bacterial
lipopolysaccharide.
Paeonol pretreatment was performed for 30 minutes prior to
lipopolysaccharide addition. Cell viability and
nitrite (the production of
nitric oxide),
tumor necrosis factor-alpha and
interleukin-1beta products were measured after
lipopolysaccharide treatment. In organotypic hippocampal slice cultures,
paeonol blocked
lipopolysaccharide-related hippocampal cell death and inhibited the release of
nitrite and
interleukin-1beta.
Paeonol was effective in inhibiting
nitric oxide release from primary microglial cells. It also reduced the
lipopolysaccharide-stimulated release of
tumor necrosis factor-alpha and interleukin-1β from microglial cells.
Paeonol possesses neuroprotective activity in a model of
inflammation-induced neurotoxicity and reduces the release of neurotoxic and proinflammatory factors in activated microglial cells.