Abstract
Purpose:
Although a wide availability of oral nutraceutical antioxidants for the apparent protection of age-related ocular diseases are available, numerous clinical studies fail to support their efficacy. Based on the hypothesis that nutraceuticals do not adequately reach the lens by oral administration, we have evaluated the ability of a unique topical nutraceutical antioxidant formulation, called Optixcare EH, to ameliorate oxidative stress in the lens and retina of rats.
Methods:
Rats were exposed to 1600 mW/cm2 of UV light for 20 minutes to induce lens changes. Diabetes was induced in rats by tail vein injection of streptozotocin. For retinal light damage Wistar rats were dark adapted for 2 weeks in dim light (5 lx) and then exposed to 1000 lx light for 3 h. Glutathione (GSH) levels were spectrophotometrically measured while retinal oxidative stress markers were measured by ELISA and western blot. Optixcare was administered b.i.d. Similarly, JHX-4 (Randazzo J.et al. PLoS One. 2011;6(7):e21926 and 26;6(4):e18980) was administered as an additional positive control (topical b.i.d. 3% suspension in Optixcare and oral 80 mg/kg/day).
Results:
Optixcare EH is composed of a viscous carbomer based vehicle containing cetrimide that delivers select antioxidants to the anterior chamber. In rats exposed to UV light both Optixcare EH and topical and oral JHX-4 is able to protect lenses against the decrease in GSH levels induced by exposure to UV light. Similarly these treatments were able to delay the progression of cataracts induced by diabetes. In light damaged rats, Optixcare EH partially reduced the levels of retinal 4-hydroxynonenal and thioredoxin while oral administration of JHX resulted in a significantly greater protection of oxidative stress in the retina.
Conclusions:
These studies suggest that topical administration of Optixcare EH as well as JHX-4 provide antioxidant protection to rats. The ingredients in Optixcare are also able to reach the posterior segment following topical administration. These studies suggest that this topical antioxidant may fill the unmet therapeutic need of providing a topical antioxidant formulation that delay the progression of cataracts and reduces the risk of AMD.
Keywords: 445 cataract •
424 antioxidants •
413 aging