Purchase this article with an account.
Takahiro Suzuki, Kenji Kawai; Effect of Autophagy in retinal pigment epithelium by amino acids starvation, high glucose, and inhibition of Neuraminidase1. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):2406.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Autophagy, self-degradative process, plays pivotal roles in cellular homeostasis. Recent years, it has been reported that autophagy control is involved in the pathology of age-related macular degeneration (AMD). Increasing attention has been paid to the implication of autophagy to various retinal diseases. In this study, we examined the conditions that affect the autophagy flux in human retinal pigment epithelium.
<br /> Human retinal pigment epithelium-derived cell line, ARPE-19 cells were cultured with/without amino acids and high glucose in the absence or presence of chloroquine. After the culture, immunofluorescent staining to LC3 was performed to assess the “LC3 puncta” formation. The expressions of LC3-I/II and p62 were quantified by Western blotting. Using small interfering RNA (siRNA), neuraminidase 1 gene was silenced in ARPE-19 cells and resultant neuraminidase 1-knock down ARPE cells were subjected to autophagy flux experiments.
Amino acids starvation and high glucose induced LC3 puncta and LC3-II and p62 expressions. Compared to amino acids starvation and high glucose induced significantly higher number of LC3 puncta and increased expressions of LC3 and p62 (9.65 fold and 7.52 fold), respectively. Neuraminidase 1 knock down ARPE-19 cells did not show significant difference.
In human retinal pigment epithelium-derived cell, ARPE-19 cell, while efficient autophagy flux was induced by amino acids starvation and high glucose, the efficiency was significantly greater under high glucose condition. This observation suggests that autophagy is implicated in diabetic retinopathy. It is reported that autophagy is required for sialylsaccharides catabolism and that neuraminidase deficiency results in retinal cell damage through the accumulation of sialyl glycoconjugates. Although significant effects were not observed in autophagy flux in<br /> neuraminidase 1 knock down cells in this study, further study will be needed to clarify whether neuraminidases are involved in autophagy in retinal cells.
This PDF is available to Subscribers Only