Diabetic Retinopathy: Vascular and Inflammatory Disease

Table 2

Vitreous mediators involved in the pathogenesis of DR.

Vitreous mediators		Function
Cytokines	IL-6	(i) Regulating immune responses; (ii) Increasing vascular permeability; (iii) Angiogenesis; (iv) Regulating expression of metalloproteinases
	IL-8	(i) Chemoattractant; (ii) Angiogenesis
	IL-1β	(i) Angiogenesis; (ii) Synthesizing collagen
	TNF-α	(i) Antiangiogenic activity, but also proangiogenic effects under certain conditions; (ii) Increasing retinal endothelial permeability; (iii) Leukocyte adhesion; (iv) Oxidation
	HMGB1	(i) Stabilizing the formation of nucleosomes and gene transcription; (ii) Attenuating retinal injury after ischemia-reperfusion; (iii) Mediating the secretion of survival factors
Transcription factors	NF-κB	(i) Regulating immune response, cell proliferation, and apoptosis; (ii) Synthesizing cytokines, chemokines, and proinflammatory molecules
	HIF-1	(i) Regulating cellular responses under acute and chronic hypoxic condition; (ii) Regulating VEGF expression
Chemokines	MCP-1	(i) Recruiting and activating macrophages; (ii) Fibrosis and angiogenesis
	IP-10	Inhibiting angiogenesis
	MIG	Angiostatic activity
	SDF-1	(i) Stimulating the mobilization of cells involved in tissue repair and promoting migration, proliferation, and differentiation of endothelial progenitor cells; (ii) Promoting repair after ischemic injury; (iii) Angiogenesis
	Fractalkine	Angiogenesis
	MIF	(i) Recruiting macrophages to the sites of inflammation; (ii) Enhancing macrophages adherence, motility, and phagocytosis
Growth factors	VEGF	(i) Increasing vascular permeability; (ii) Angiogenesis; (iii) Endothelial cell migration and survival; (iv) Expression of ICAM and VCAM-1
	PGF	(i) Potentiating the action of VEGF; (ii) Stimulating endothelial cell proliferation, migration, and angiogenesis
	Tenascin-C	(i) Modulating cell growth and cell adhesion; (ii) Involved in sprouting of endothelial cells
	IGF 1	(i) Regulating the proliferation and differentiation of several cell types; (ii) Stimulating the production of VEGF
	bFGR	(i) Survival/maturation of neurons and glial cells; (ii) Angiogenesis
	HGF	(i) Modulating the motility, growth, and morphogenesis of various cell types; (ii) Angiogenesis
	NGF	Stimulating Muller cells to produce bFGF, which in turn stimulates endothelial cell proliferation and secretion of VEGF
	CTGF	Stimulating proliferation, angiogenesis, migration, extracellular matrix production, cell attachment, cell survival, and apoptosis
	Stem cell factor	(i) Involved in survival and differentiation of hematopoietic stem cells; (ii) Promoting survival, migration, differentiation, and capillary tube formation of endothelial cells
	EPO	Antioxidant, anti-inflammatory, proangiogenic, neuroprotective, and antiapoptotic properties
	Adiponectin	Anti-inflammatory and antiatherosclerotic properties
Adhesion molecules	ICAM-1, VCAM-1, and E-selectin	Recruiting leukocytes
	Soluble vascular adhesion protein	Recruiting leukocytes