Abstract
Purpose :
We previously reported that three novel agents, which contain the oral sodium-dependent glucose cotransporter (SGLT) 2 inhibitor tofogliflozin and supplementation with trapa bispinosa roxb. extract (TBE) and lutein and fenofibrate nano-eyedrops (FenoNano), improved retinal blood flow (RBF) dysregulation in diabetic mice. We examined the role of oxidative stress in RBF dysregulation in type 2 diabetic mice using these therapeutic agents.
Methods :
We divided the mice into 5 groups: normal blood glucose mice (db/m mice), untreated type 2 diabetic mice (db/db mice), db/db mice treated with SGLT2 inhibitor tofogliflozin (feed containing tofogliflozin), supplemented mice (feed containing TBE and lutein), and FenoNano eyedrop-treated mice (1% FenoNano eyedrops twice daily) (n=6 each). We compared the intensity of fluorescence immunostaining with oxidative stress markers nitrotyrosine (NO2-Y) and 8-OHdG in retinal tissue sections from the ganglion cell layer (GCL) to the outer nuclear layer (ONL). We also evaluated the intensity of the oxidative stress markers in the retinal vascular area detected by co-staining with lectin.
Results :
The intensities of NO2-Y and 8-OHdG from the GCL to the ONL and retinal vascular areas increased in the untreated diabetic mice compared to the db/m control mice and significantly decreased with the SGLT2 inhibitor tofogliflozin, supplementation, and FenoNano Eyedrop groups. No significant differences were seen in the intensities of NO2-Y and 8-OHdG in treated mice compared with those in normal glucose db/m mice.
Conclusions :
The beneficial effects of novel treatment agents, SGLT2 inhibitor, supplementation with TBE and lutein, and Feno-Nano Eyedrops on the improved RBF dysregulation in type 2 diabetic mice may result from decreased retinal oxidative stress.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.