Autor(es): Fernandes, Ana R. ; Santos, Tiago dos ; Granja, Pedro L. ; Sanchez-Lopez, Elena ; Garcia, Maria L. ; Silva, Amelia M. ; Souto, Eliana B.
Data: 2022
Identificador Persistente: https://hdl.handle.net/1822/76243
Origem: RepositóriUM - Universidade do Minho
Assunto(s): Cationic nanoemulsions; Triamcinolone acetonide; Vascular Endothelial Growth Factor; Tumor Necrosis Factor alpha; Choroidal neovascularization; Tumor Necrosis Factor alpha, Choroidal neovascularization
Age-related macular degeneration (AMD) is defined as a degenerative, progressive and multifactorial disorder that affects the macula with a complex etiology. The retinal pigment epithelium is a monolayer of cells that has the function to separate the surface of the choroid from the neural retina that is involved in the signal transduction leading to vision. The blood-aqueous barrier and the blood retinal barrier limit the permeation of drugs into the retina and thereby reducing their efficacy. Triamcinolone acetonide (TA) is widely used as anti-inflammatory and immunomodulatory drug that promotes the inhibition of the inflammatory processes. The factors that stimulate or inhibit angiogenesis in AMD create a local balance that is responsible for the growth of sub-retinal neovascularization. In AMD, the main angiogenic stimulus is the vascular endothelial growth factor (VEGF). In this work, nanoemulsions with cationic surfactants (mono- and dicationic DABCO and quinuclidine) were produced to deliver TA, and were found to reduce the production of tumor necrosis factor alpha (TNF-), which stimulates the choroidal neovascularization development by upregulating the VEGF production, and consequently decreased the VEGF levels. Our results support the potential use of mono- and dicationic DABCO and quinuclidine-based cationic nanoemulsions for the delivery of TA in the treatment of AMD.
