**5.** *Drosophila* **gut brain axis: role in health and disease**

Various studies have suggested that intestinal health has a significant impact on neurodegeneration. Specifically, dysregulation of GBA cross talk has been associated with metabolic syndrome [265, 266] and psychiatric disorders. GBA is largely mediated by CNS, ENS and intestinal microbiota. With its much simpler gut microbiota (1–30 taxa) as opposed to vertebrates intestine (1–500 taxa) [267], *Drosophila* intestine provides an experimental tools where whole microbiota can be removed in its entirety to perform screens to probe the relation between gut flora and the brain disorders.
