Abstract
Abstract: :
Purpose:To investigate the mRNA expression of facilitative and sodium–dependent glucose transporters in bovine CBE, with the aim of furthering our understanding of the mechanisms by which glucose is transported into the anterior chamber. This may help in developing strategies for better ocular glycemic control and the prevention of diabetic cataract formation. Methods:Bovine CBE were isolated within an hour post mortem and immersed in RNAlater. RNA was extracted from the fresh bovine CBE in the pars plicata and pars plana regions. Reverse transcriptase – polymerase chain reaction (RT–PCR) was carried out to examine the mRNA expression of five members of the facilitative glucose transporter family (GLUT1–5), and two members of the sodium–dependent glucose transporter family (SGLT1–2) in these tissues. The amplified PCR products were sequenced to confirm their identity. RNA from fresh bovine kidney was used as a positive control for RT–PCR. Results:RT–PCR revealed the presence of mRNAs for GLUT1, GLUT3, GLUT4 and GLUT5, but not GLUT2 and SGLT1, in both the pars plicata and pars plana of the bovine CBE. In addition, SGLT2–like mRNA expression was found in the pars plana only. The results of the DNA sequencing were analysed by BLAST searches against the GenBank non–redundant database, and in each case the results showed the highest degree of alignment to their corresponding sequence in the nucleotide database. Conclusion:These results confirm electrophysiological findings that glucose transport across the bovine CBE is mainly driven by facilitative glucose transporter proteins. Therefore, the regulation of these GLUT proteins is likely to be fundamental in controlling the aqueous glycemic level and may help to lower the risk of diabetic cataract development.
Keywords: ciliary body • cataract