A cataract is a clouding of the normally clear lens of an eye. Changes in the lens proteins affect how the lens refracts light and reduce its clarity, therefore decreasing visual perception. Chemical modification of these lens proteins lead to a change in lens colour. New cortical fibres are produced concentrically and lead to thickening and hardening of the lens in nuclear sclerosis, which often appears yellow and can increase the focusing power of the natural lens. Increasing myopia can also be evidence of a progressing nuclear sclerotic cataract.
Advanced glycation end products (AGEs) are one of the key substances that lead to cataract. Carnosine not only suppresses the formation of AGEs, but also protects the normal proteins from the toxic effects of the already-formed AGEs. This finding is quite new, from 2000, when were published works of the Royal College, University of London (C. Brownson, Hipkiss AR, et al.) on the effects of carnosine. Their experiments are based on the following: glycosylated ovalbumin has been created (egg white protein is damaged by methylglyoxal, a known substance for glycosylation), then damaged ovalbumin was mixed with a crystalline, eye lens protein and caused the formation of cross-links into the crystalline and subsequently its opacity. Carnosine not only prevented damage of the crystalline, but has caused the recovery of its structure. Confirming carnosine-induced anti-glycating effect in cataract, another group of researchers suggested that carnosine represents a promising agent in the treatment of diabetic cataract Abdelkader, Longman, Alany, Pierscionek, 2016).
A glaucoma is a disease that damages an eye’s optic nerve. It usually happens when fluid accumulates in the front part of an eye. That extra fluid increases the pressure in the eye, damaging the optic nerve.
Additional studies have confirmed the positive effects of carnosine in developed glaucoma, as well as for the prevention of the same. This discovery is extremely important for patients suffering from Alzheimer’s and Parkinson’s disease, in which glaucoma often occurs. The influence of eye drops on the basis of carnosine to delay eye and vision aging has been definitely proven. It was revealed that it is almost 100% effective in cases of primary senile cataract and 80% effective in cases of developed senile cataract. The effect of carnosine as an agent that acts as an antioxidant at the mitochondrial level is associated showed significant improvements in alleviation of glaucoma symptoms (Rolle et al, 2020; Babizhayev, 2016, Babizhayev, 2016). In the blood-depleted retina, carnosine has a protective effect as it prevents the loss of retinal ganglion cells (Ji, Park, Heo, Park & Park, 2014)
Abdelkader, H., Longman, M., Alany, R. G., & Pierscionek, B. (2016). On the anticataractogenic effects of L-carnosine: is it best described as an antioxidant, metal-chelating agent or glycation inhibitor?. Oxidative medicine and cellular longevity, 2016.
Babizhayev M. A. (2016). Generation of reactive oxygen species in the anterior eye segment. Synergistic codrugs of N-acetylcarnosine lubricant eye drops and mitochondria-targeted antioxidant act as a powerful therapeutic platform for the treatment of cataracts and primary open-angle glaucoma. BBA clinical, 6, 49–68. https://doi.org/10.1016/j.bbacli.2016.04.004
Babizhayev, M. A., & Yegorov, Y. E. (2016). Reactive Oxygen Species and the Aging Eye: Specific Role of Metabolically Active Mitochondria in Maintaining Lens Function and in the Initiation of the Oxidation-Induced Maturity Onset Cataract–A Novel Platform of Mitochondria-Targeted Antioxidants With Broad Therapeutic Potential for Redox Regulation and Detoxification of Oxidants in Eye Diseases. American journal of therapeutics, 23(1), e98–e117. https://doi.org/10.1097/MJT.0b013e3181ea31ff
Rolle, T., Dallorto, L., Rossatto, S., Curto, D., & Nuzzi, R. (2020). Assessing the Performance of Daily Intake of a Homotaurine, Carnosine, Forskolin, Vitamin B2, Vitamin B6, and Magnesium Based Food Supplement for the Maintenance of Visual Function in Patients with Primary Open Angle Glaucoma. Journal of ophthalmology, 2020, 7879436. https://doi.org/10.1155/2020/7879436
(2014) The Neuroprotective Effect of Carnosine (β-Alanyl-l-Histidine) on Retinal Ganglion Cell Following Ischemia-Reperfusion Injury, Current Eye Research, 39:6, 634-641, DOI: 10.3109/02713683.2013.855235