advertisement
Saturated fatty acids and sugar-sweetened beverages are major components of the Western diet, a nutritional consumption pattern associated with several adverse health outcomes. Chrysostomou and colleagues placed mice on a high-fat, high-sucrose (HFS) diet for 6 weeks and found no changes in retinal ganglion cell (RGC) function as measured by electroretinography (ERG) and no changes in intraocular pressure (IOP) compared to a control diet containing a lower content of fat and sucrose. Then IOP was raised to ~50mmHg for 30 minutes via cannulation of the anterior chamber. This IOP elevation did not cause structural changes in the retina but did result in reduced positive scotopic threshold response (pSTR) amplitudes, responses that localize to the RGC layer. At one week after exposure to elevated IOP, pSTR amplitudes recovered to near normal in mice on the control diet but remained reduced in mice on the HFS diet. This vulnerability to RGC dysfunction was not rescued with an exercise regimen consisting of 60 minutes of swimming, 5 days per week for 1 week after induction of elevated IOP. More significant IOP insults resulting or longer periods of exercise were not tested. The authors note that the HSF diet did not produce statistically significant changes in body mass index or serum glucose levels. They hypothesize that the HSF diet induces oxidative stress in neuronal cells and provide evidence for increased glial fibrillary acidic protein immunoreactivity in the RGC layer of mice fed the HFS diet after IOP elevation compared to mice on the control diet who also had similar exposure to elevated IOP. The authors discuss other mechanisms but do not provide data to address them. Overall, these data provide another reason to curtail intakes of foods high in saturated fats and sucrose.