Drosophila as a model system for studying lifespan and neuroprotective activities of plant-derived compounds

The fruit fly, Drosophila melanogaster, has been intensively used as a genetic model system for basic and applied research on human neurological diseases because of advantages over mammalian model systems such as ease of laboratory maintenance and genetic manipulations. Disease-associated gene mutations, whether endogenous or transgenically-inserted, often cause phenotypes in vivo that are similar to the clinical features of the human disorder. The Drosophila genome is simpler than that of mammals, in terms of gene and chromosome number, but nonetheless demonstrates extraordinary phylogenetic conservation of gene structure and function, especially notable among the genes whose mutations cause neurodevelopmental, neuropsychiatric, or neurodegenerative disorders. In addition, its well-established neuroanatomical, developmental, and molecular genetic research techniques allow many laboratories worldwide to study complex biological and genetic processes. Based on these merits of the Drosophila model system, it has been used for screening lifespan expansion and neuroprotective activities of plant extracts or their secondary metabolites to counteract pathological events such as mitochondrial damage by oxidative stress, which may cause sporadic neurodegenerative diseases. In this review, we have summarized that the fruit fly can be used for early-stage drug discovery and development to identify novel plant-derived compounds to protect against neurodegeneration in Alzheimer's disease and Parkinson's disease, and other neurological disorders caused by oxidative stress. Thus, the Drosophila system can directly or indirectly contribute to translational research for new therapeutic strategies to prevent or ameliorate neurodegenerative diseases.