Changes in aqueous and vitreous inflammatory cytokine levels in proliferative diabetic retinopathy: a systematic review and meta-analysis

Abstract

BACKGROUND: Diabetic retinopathy is a major complication of diabetes mellitus, where in its most advanced form ischemic changes lead to the development of retinal neovascularization, termed proliferative diabetic retinopathy (PDR). While the development of PDR is often associated with angiogenic and inflammatory cytokines, studies differ on which cytokines are implicated in disease pathogenesis and on the strength of these associations. We therefore conducted a systematic review and meta-analysis to quantitatively assess the existing body of data on intraocular cytokines as biomarkers in PDR. METHODS: A comprehensive search of the literature without year limitation was conducted to January 18, 2021, which identified 341 studies assessing vitreous or aqueous cytokine levels in PDR, accounting for 10379 eyes with PDR and 6269 eyes from healthy controls. Effect sizes were calculated as standardized mean differences (SMD) of cytokine concentrations between PDR and control patients.

Vitreous protein networks around ANG2 and VEGF in proliferative diabetic retinopathy and the differential effects of aflibercept versus bevacizumab pre-treatment

“…However, in general the results confirm the data of our previous study. Our results are also in accordance with previously published studies (reviewed by Kaštelan et al 35 and Mason et al 36 ), but we present several novel findings.…”

Convolvulus pluricaulis Choisy’s Extraction, Chemical Characterization and Evaluation of the Potential Effects on Glycaemic Balance in a 3T3-L1 Adipocyte Cell Model

“…Of note, high levels of eotaxin in serum from diabetic patients have recently been reported by Okdahl et al [ 58 ], as well as in the vitreous fluid of subjects affected by diabetic retinopathy [ 59 ], which represents an important and invalidating complication of diabetes. A similar involvement has been demonstrated for GM-CSF, whose concentrations resulted significantly elevated in proliferative diabetic retinopathy [ 60 , 61 ]. This clear correlation between diabetes and its complications and inflammation, calls for a continuous effort in researching alternative therapeutic approaches which are able to act in a double direction, performing an anti-inflammatory effect and lowering circulating glucose levels.…”

Systemic Cytokines in Retinopathy of Prematurity

“…It primarily attracts eosinophils, mediates inflammation, and promotes angiogenesis via the receptor CCR3 [ 195 , 196 ]. Its expression in the vitreous, neurosensory retina, or choroid has been implicated in the pathogenesis of AMD [ 196 ], proliferative diabetic retinopathy, and choroidal neovascularization [ 197 ]. Likewise, vitreous eotaxin concentrations were significantly higher in ROP eyes than in non-ROP controls [ 23 ].…”