Purchase this article with an account.
R. J. Walker, J. J. Steinle; Inflammatory Cytokines Modulated by Beta-Adrenergic Receptors in Retinal Muller Cells. Invest. Ophthalmol. Vis. Sci. 2007;48(13):4989.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To determine if ß-adrenergic receptors are involved in the regulation of inflammatory cytokines in Muller cells in a hyperglycemic environment.
Real-time polymerase chain reaction was carried out to measure steady-state mRNA expression for the following inflammatory markers: iNOS, TNFα, Il-1ß, and ICAM1. Western blot analysis and ELISA assays were performed to determine the protein expression of these inflammatory markers and PGE2.
Isoproterenol significantly decreased protein levels of iNOS, TNFα, and Il-1ß in cells treated with high glucose as early as one hour, compared to cells with no treatment. There were no significant changes observed in protein levels of ICAM1 and PGE2. Steady-state mRNA levels for iNOS were significantly decreased after one hour, whereas ICAM1 gene expression was significantly increased after one hour. Gene expression of Il-1ß was significantly increased after six hours of treatment, whereas TNFα showed no significant changes in steady-state mRNA levels.
These results suggest that adrenergic receptors are involved in the increase in protein levels of TNFα, IL-1ß, and both gene expression and protein levels of iNOS. ß-adrenergic receptor agonists had no effect on PGE2 levels. Overall, agonists to ß-adrenergic receptor signaling may alleviate some of the increased cytokine release noted in diabetic retinopathy.
This PDF is available to Subscribers Only