Promoting Recovery by Inhibiting PDE10A-Mediated Inflammation
Abstract
The first goal was to determine the effects of TP-10 treatment in nerve and muscle recovery after sciatic nerve injury. Using sciatic nerve crush injury, we obtained reproducible damage as measured by muscle force and CatWalk gait analyses. To find the optimal dose of PDE10A inhibitor to improve these parameters, we used two different PDE10A specific inhibitors, MP-10 and TP-10. We optimized the dose using an in vitro macrophage model. Specifically, we stimulated inflammasome activation and pyroptosis to show the importance of PDE10A in macrophage mediated inflammation, inflammasome activation and pyroptosis (a specific type of programmed cell death that releases high amounts of inflammatory cytokines such as IL-b and IL-18. To stimulate pyroptosis, we incubated macrophages with lipopolysaccharide (LPS) and nigericin. Optimal protection was a 50 percent reduction in cell death with 3 (Mu)M MP-10 which correlated with a 60 percent reduction in IL-Ib release. We studied the process of pyroptosis that requires the clustering an adaptor protein called ASC in freshly isolated peritoneal macrophages.TP-10 at 3 M inhibited ASC clustering and pyroptosis by 66 percent. The second goal was to define the effect of PDE10A inhibition on cytokine expression and after nerve injury. We performed immunohistochemistry on sham and crush injury sciatic nerve sections. There was a 5-fold increase in PDE10A after crush injury. Next, we performed a cytokine array on injured nerve and found significantly increased IL-1b, IL-18, and myeloperoxidase. We confirmed increases in these cytokines by performing an immunoblot. In summary, we showed that pyroptosis and "cytokine storm" were present after sciatic crush injury. TP-10 or MP-10 reduced inflammasome formation and activation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2022
- Accession Number
- AD1179178
Entities
People
- Bradford C. Berk
Organizations
- University of Rochester