Investigating the role of Hippo pathway in Type 1 Diabetes

The prevalence of type 1 diabetes (T1D) is on the rise, posing a significant burden on healthcare systems. T1D results from the immune system mistakenly attacking insulinproducing pancreatic βcells, necessitating lifelong insulin treatment and continuous monitoring of blood sugar levels. The complex inflammatory nature of T1D, coupled with substantial gaps in our understanding of the molecular drivers behind βcell destruction, presents challenges in developing effective treatment strategies.

The primary challenge this project tackles is the need for more effective approaches to treat T1D by addressing the underlying causethe destruction of pancreatic βcells. This requires a thorough understanding of the molecular mechanisms responsible for βcell damage. This project centers around the role of the Hippo signalling pathway, known for its involvement in regulating organ size and tissue hemostasis. We were the first to demonstrate the pivotal role of the Hippo signaling pathway in βcell apoptosis, regeneration, and function. Pilot data indicate that the terminal effector of the Hippo pathway, YesAssociated Protein (YAP), typically repressed in mature βcells, is upregulated in both exocrine and endocrine compartments of individuals with T1D, acting as a potential regulator of βcell apoptosis and islet inflammation. Therefore, elevated expression of YAP is a novel metabolic aspect of T1D. We hypothesize that elucidating the molecular mechanisms linked to YAPinduced damage is crucial for the development of targeted therapies for T1D.

The project’s primary objectives are to unravel the role of YAP and its molecular partners in T1D. These objectives include: (1) Identifying how YAP expression is activated in T1D and characterizing the cell types responsible for YAP upregulation. (2) Investigating the expression and cellular localization of YAP partners. (3) Determining spatial transcriptome profiling of YAPexpressing pancreatic cells in T1D to identify and characterize gene programs and signaling events shaping their niche identities. Utilizing the nPOD collection of healthy and diseased human pancreatic tissue, the project aims to unravel the molecular aspects of islet autoimmunity and βcell destruction in T1D. This knowledge will serve as the foundation for new therapeutic strategies targeting the Hippo pathway to protect βcells in T1D.