Increasing evidence on the adverse health impacts of microplastics (MPs) is available, but their associated risks to the well-being of humans and long-term impacts are poorly understood. An indicator of the remote effects of MPs may be their influence on the rate of aging. To assess the effects of MPs on the aging process, we used accelerated senescence OXYS rats that develop a complex of geriatric diseases. We prepared the polyethylene terephthalate MPs (2-6 microns in size) and in OXYS and Wistar (maternal strain) rats assessed the influence of chronic administration of MPs (10 or 100 mg/kg per day from age 1.5 to 3.5 months,) on the hematological and biochemical blood parameters, spatial learning, and memory. In addition, the effects of MPs on the development of cataracts and retinopathy, similar to age-related macular degeneration (AMD), in OXYS rats were assessed. We found that in the absence of significant changes in standard clinical blood parameters, chronic MP administration negatively affected the cognitive functions of both Wistar rats and OXYS rats. Additionally, a dose of 100 mg/kg MPs contributed to cataract and AMD progression in OXYS rats. Our results suggest that MPs may increase the rate of aging and, in the long term, lifespan.
Keywords: Alzheimer’s disease; OXYS rats; age-related macular degeneration; cognitive ability; memory; microplastic; polymers.