Intravitreal itraconazole inhibits laser-induced choroidal neovascularization in rats

Abstract

Choroidal neovascularization (CNV) is a major cause of severe visual loss in patients with age-related macular degeneration (AMD). Recently, itraconazole has shown potent and dose-dependent inhibition of tumor-associated angiogenesis. We evaluated the anti-angiogenic effect of itraconazole in a rat model of laser-induced CNV. After laser photocoagulation in each eye to cause CNV, right eyes were administered intravitreal injections of itraconazole; left eyes received balanced salt solution (BSS) as controls. On day 14 after laser induction, fluorescein angiography (FA) was used to assess abnormal vascular leakage. Flattened retinal pigment epithelium (RPE)-choroid tissue complex was stained with Alexa Fluor 594-conjugated isolectin B4 to measure the CNV area and volume. Vascular endothelial growth factor receptor 2 (VEGFR2) mRNA and protein expression was determined 1, 4, 7, and 14 days after intravitreal injection by quantitative RT-PCR or Western blot. VEGF levels were analyzed by enzyme-linked immunosorbent assay (ELISA). Intravitreal itraconazole significantly reduced leakage from CNV as assessed by FA and CNV area and volume on flat mounts compared with intravitreal BSS (p = 0.002 for CNV leakage, p<0.001 for CNV area and volume). Quantitative RT-PCR showed significantly lower expression of VEGFR2 mRNA in the RPE-choroid complexes of itraconazole-injected eyes than those of BSS-injected eyes on days 7 and 14 (p = 0.003 and p = 0.006). Western blots indicated that VEGFR2 was downregulated after itraconazole treatment. ELISA showed a significant difference in VEGF level between itraconazole-injected and BSS-injected eyes on days 7 and 14 (p = 0.04 and p = 0.001). Our study demonstrated that intravitreal itraconazole significantly inhibited the development of laser-induced CNV in rats. Itraconazole had anti-angiogenic activity along with the reduction of VEGFR2 and VEGF levels. Itraconazole may prove beneficial for treating CNV as an alternative or adjunct to other therapies.

Intravitreal injection of peptides PnPa11 and PnPa13, derivatives of Phoneutria nigriventer spider venom, prevents retinal damage

“…Besides that, the needle was held in place for 30seconds to prevent it from escaping the application site. The volume of intravitreal injection was set to 10 µL [28]. Each concentration was calculated based on the dilution that occurs in the vitreous humor (for adult rats, the vitreous volume is about 50 μL) [29].…”

Activator of G-protein signaling 8 is involved in VEGF-induced choroidal neovascularization

“…Furthermore, the expression of c-terminal AGS8 increases the expression of VEGFR-2 in cultured cells 15 , which might due to the stabilization of VEGFR-2 in the AGS8-Gβγ protein complex. Recently, it was reported that VEGF mRNA and protein expression are induced in RPE cells and the receptor VEGFR-2 is also present in choroidal ECs in a laser-induced murine AMD model 33 . Here, AGS8 was induced into the choroidal ECs in the neovasculature and might have contributed to development of CNV in choroidal ECs by regulating the VEGF signaling pathway.…”

Antiviral Activity of Itraconazole against Echovirus 30 InfectionIn Vitro

“…Itraconazole is a triazole antifungal drug that inhibits the enzyme lanosterol 14-α-demethylase, which is important in ergosterol synthesis in fungi [ 6 ]. It possesses greater activity than fluconazole, is less expensive than newer triazoles, and unlike its predecessor, ketoconazole, exerts minimal effects on mammalian enzymes [ 7 ].…”