Increased levels of vascular endothelial growth factor and interleukin-6 in the aqueous humor of diabetics with macular edema.
OBJECTIVE
To investigate the relationship between diabetic macular edema and the levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) in aqueous humor and plasma.


METHODS
Comparative cross-sectional study.


METHODS
Fifty-four eyes from 54 diabetic patients were used. The concentrations of VEGF and IL-6 in undiluted aqueous specimens (obtained from the eyes during cataract surgery) and in plasma were measured by an enzyme-linked immunosorbent assay. To assess blood-aqueous barrier function, the aqueous flare intensity was measured by a laser flare-cell meter as an estimate of the aqueous protein level.


RESULTS
The aqueous levels of VEGF and IL-6 were significantly correlated with the severity of macular edema (rho = 0.628, P <.001 and rho = 0.517, P <.01, respectively), as well as with the aqueous protein concentration (rho = 0.618, P <.001 and rho = 0.588, P <.001, respectively). Aqueous levels of VEGF and IL-6 were significantly higher than their respective plasma levels (both P <.001). In addition, the aqueous level of VEGF was significantly correlated with that of IL-6 (rho = 0.537, P <.01). Furthermore, the status of the posterior vitreous significantly correlated with the severity of macular edema (rho = 0.618, P <.0001).


CONCLUSIONS
These results suggest that both VEGF and IL-6 are produced together in the intraocular tissues, and are involved in the pathogenesis of macular edema.
Funatsu
Hideharu
H
Department of Ophthalmology, Diabetes Center, Tokyo Women's Medical University, Tokyo, Japan. tfunatsu@nifty.com
Yamashita
Hidetoshi
H
Noma
Hidetaka
H
Mimura
Tatsuya
T
Yamashita
Tetsuji
T
Hori
Sadao
S
D000328:Adult; D000368:Aged; D001082:Aqueous Humor / Q000378:metabolism*; D018916:Blood-Aqueous Barrier; D003430:Cross-Sectional Studies; D003930:Diabetic Retinopathy / Q000145:classification / Q000150:complications / Q000378:metabolism*; D016228:Endothelial Growth Factors / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005136:Eye Proteins / Q000378:metabolism; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D008222:Lymphokines / Q000378:metabolism*; D008269:Macular Edema / Q000145:classification / Q000209:etiology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors
D016228:Endothelial Growth Factors; D005136:Eye Proteins; D015850:Interleukin-6; D008222:Lymphokines; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors