Danio rerio and Nothobranchius guentheri as Model Organisms in Preclinical Studies of Geroprotectors Using the Example of Meclofenoxate

The nootropic and antioxidant drug meclofenoxate (MF) is a promising candidate for geroprotectors with cholinergic and antioxidant effects. The study determined the toxicity of MF on Danio rerio embryos, as well as its effect on lifespan and external markers of aging in Nothobranchius guentheri, taking into account sex differences. The fish were kept in a closed water supply system at 27°C. According to the results of the studies, the LC50 of MF in D. rerio was 75 mg/L, which corresponds to moderate toxicity. When MF was tested on N. guentheri, the drug increased the median lifespan of males by 32.8% (up to 17.9 months) and females by 12.7% (up to 11 months) and did not affect the maximum lifespan. At the same time, males showed a slowdown in the manifestation of age-related signs (skeletal curvature, loss of coloration), while females, on the contrary, showed an increase in certain signs (cystic eggs, eye leukoma, spinal deformation).