Intraocular Pressure-Lowering Efficacy and Safety of Fermented Cordyceps cicadae Mycelia

Abstract

High intraocular pressure is one of the main risk factors for glaucoma. Chronic intraocular pressure may result in compression of the optic nerve with a consequence of optic nerve damage and atrophy, which can cause problems with vision and blindness in severe cases. Cordyceps cicadae is a traditional Chinese medicine that has a long history of use. It has important physiological roles in renal protection, blood sugar regulation, and eye health care. However, there is limited evidence regarding the effect of Cordyceps cicadae on intraocular pressure reduction. Therefore, this study aims to use Cordyceps cicadae mycelia using liquid fermentation and evaluate its safety and ability to lower intraocular pressure in the animal model of white rabbits. For safety assessment, 2.5 (low dose) and 25 (high-dose) mg/kg b.w. of Cordyceps cicadae mycelia were orally administered. After continuous feeding for 10 days, blood and tissues were collected for analysis. Results showed that in hematological, serum biochemical, and liver and kidney histological analyses, no observable lesions related to the test substance were found. For efficacy assessment, a single dose of Cordyceps cicadae mycelia from different fermentation days was orally administered, and the intraocular pressures of the rabbits were measured at different time points after feeding. All rabbits showed reduced intraocular pressure reduction in the first and third hour after feeding Cordyceps cicadae mycelia from different fermentation days. Taken together, these findings suggest that short-term oral supplementation of Cordyceps cicadae mycelia shows no toxicity in rabbits and has a beneficial effect on intraocular pressure-lowering efficacy.