The last decade has witnessed an increasing interest for the role played by the
peroxisome proliferator-activated receptor-gamma (
PPAR-gamma) in controlling
inflammation in peripheral organs as well as in the brain. Activation of
PPAR-gamma has been shown to control the response of microglial cells, the main macrophage population found in brain parenchyma, and limit the
inflammation. The anti-inflammatory capacity of
PPAR-gamma agonists has led to the hypothesis that
PPAR-gamma might be targeted to modulate degenerative
brain diseases in which
inflammation has been increasingly recognized as a significant component. Recent experimental evidence suggests that
PPAR-gamma agonists could be exploited to treat ocular diseases such as
diabetic retinopathy,
age-related macular degeneration, autoimmune
uveitis, and
optic neuritis where
inflammation has relevant role. Additional
PPAR-gamma agonist beneficial effects could involve amelioration of
retinal microcirculation and inhibition of neovascularization. However,
PPAR-gamma activation could, in some instances, aggravate the ocular pathology, for example, by increasing the synthesis of
vascular endothelial growth factor, a proangiogenic factor that could trigger a vicious circle and further deteriorate
retinal perfusion. The development of new in vivo and in vitro models to study ocular
inflammation and how to modulate for the eye benefit will be instrumental for the search of effective
therapies.