In a Parkinson’s disease (PD) model, the TG2 KO mice reversed the behavioral manifestations of PD by downregulating the release of inflammatory mediators such as histamine, leukotrienes, and cytokines by mast cells in the substantia nigra, suggesting that TG2 might contribute to neuroinflammation and neurodegeneration [98]. Here, TGM2 is linked to Parkinson disease.