Leaf miRNAs of Withania somnifera Negatively Regulate the Aging-Associated Genes in C. elegans

Abstract

Aging is a physiological process that culminates in cellular senescence, a phenomenon that has significant implications for health and longevity. Plant-based therapeutics, particularly the root of Withania somnifera, have been reported to delay the onset and progression of aging and its associated disorders, including Alzheimer's disease, Parkinson's disease, and other neurodegenerative disorders. However, the role of leaf-derived microRNAs (miRNAs) from W. somnifera in the molecular regulation of genes involved in aging remains poorly understood. Caenorhabditis elegans serves as an indispensable model organism for studying aging-associated gene regulation due to its short lifespan, conserved human orthologs, and ease of laboratory cultivation. In this study, we explored the regulatory interactions between miRNAs derived from the leaf tissues of W. somnifera and aging-associated genes, utilizing C. elegans as a model organism. We employed bioinformatics to identify miRNAs that interact with aging-associated genes in C. elegans and found that three specific miRNAs in the leaf tissue of W. somnifera interacted with these genes. To assess the physiological effects of these miRNAs on C. elegans, we conducted biochemical assays, including lifespan, chemotaxis, and stress resistance assays. Additionally, we investigated the differential gene expression of the interacting genes in the presence and absence of W. somnifera leaf miRNA treatment using real-time PCR. The results indicated that the expression levels of the age-1 and sel-12 genes were significantly downregulated, while the apl-1 gene was upregulated following treatment with leaf miRNAs in C. elegans. These findings suggest that miRNAs derived from W. somnifera leaves may play a crucial role in regulating aging-associated gene expression. This is the first study, to our knowledge, that identifies the miRNAs of W. somnifera leaf involved in aging-associated gene regulation, thereby paving the way for future research into the therapeutic potential of plant-derived miRNAs in combating age-related disorders.

Keywords: C. elegans; W. somnifera; Aging; Cross-kingdom regulation; MiRNAs.