PURPOSE. Leptin is a cytokine that regulates energy metabolism and is linke
d to diabetes mellitus through its metabolic actions. Leptin is angiogenic
and promotes wound healing, and therefore this investigation was conducted
to determine whether leptin is associated with neovascular and fibrotic com
plications of diabetes and other retinopathies.
METHODS. Serum and vitreous samples were collected from patients classified
by the presence and type of diabetic retinopathy or other ocular diseases.
Leptin was measured in serum and vitreous by radioimmunoassay, and leptin
and Leptin receptor were localized in epiretinal membranes immunohistochemi
cally.
RESULTS. Leptin levels in serum and vitreous were higher in patients with d
iabetes than in those without, and vitreous leptin concentrations were espe
cially elevated in patients with proliferative diabetic retinopathy or reti
nal detachment. Leptin and leptin receptor were detected in fibrovascular e
piretinal membrane of patients with diabetes.
CONCLUSIONS. Leptin in human vitreous is elevated in proliferative diabetic
retinopathy and retinal detachment and is present in fibrovascular epireti
nal tissue. These data suggest an involvement of leptin in retinal disease.