Abstract
Purpose :
The administration of high-fat diets (HFD) can induce hyperglycemia and metabolic disorders in mice and has been associated with diabetic retinopathy. The purpose of the current study was to determine the effects of acute high-fat diet feeding on retinal degenerative diseases.
Methods :
Retinal degeneration 10 (rd10) and C57BL/6J mice 19 days old were fed for 2 or 3 weeks either with a normal chow (5,5% fat kcal) or with a high-fat diet (61,6% fat kcal). The animals were weighed and blood glucose curves were determined before and after each of the two dietary periods. The retinal function was evaluated by optomotor test and electroretinography, and the morphology of the retinas was performed using vertical retinal cryostat sections stained either with hematoxylin or immunohistochemistry techniques.
Results :
The animals fed with short-term HFD gained significantly more weight (C57BL/6J: p<0.05 after 3 weeks of diet; rd10: p<0.05 after 2 and 3 weeks of diet) and developed reversible glucose intolerance (p<0.05 and p<0.001 30 min after glucose administration in C57BL/6J and rd10, respectively). There were no significative differences between C57BL/6J mice electroretinographic responses. Otherwise, in rd10 mice, 2 or 3 weeks of high-fat diet produced faster deterioration of retinal responsiveness with decreased a- and b-wave amplitudes (p<0.001 in both of them) and lower visual acuity (p<0.001). This functional decrease was paralleled by higher reduction in the number of photoreceptor rows and shorter outer and inner segments. Moreover, a worsening of synaptic connectivity was observed with decreased density of presynaptic photoreceptor terminals and retraction of bipolar and horizontal cell dendrites. High-fat diet-induced changes in retinal neurons were accompanied by an increment of microglial cells and higher Müller cell reactivity.
Conclusions :
Short-term high-fat feeding accelerates pathology progression in retinal degenerative diseases. The results suggest that the consumption of a high-fat diet in patients suffering from ocular neurodegenerative diseases could exacerbate the progress of the disease.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.