NOS2 and Parkinson disease: In consistent with the immunofluorescence data, Peli1 deficiency markedly inhibited LPS-induced expression of Nos2 and proinflammatory genes (Il1b, Il6, Tnf) in SN as compared to that injected with PBS (Fig. 3b), suggesting that Peli1 served as a positive regulator of neuroinflammation in PD pathology.