Lnc-USP28-6/ZBTB16 axis orchestrates NLRP3 inflammasome activation and α-synuclein SUMOylation to drive Parkinson's disease pathogenesis.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by neuroinflammation and the aggregation of α-synuclein (α-syn), which lead to progressive neuronal loss, yet regulatory mechanisms remain elusive. Zinc finger and BTB domain-containing protein 16 (ZBTB16) has been implicated as a critical nexus integrating proteostatic dysregulation with neuroimmune axis activation in neuropathogenesis. However, its specific role and molecular mechanisms in PD remain poorly understood. Building upon the initial RNA sequencing analysis showing ZBTB16 upregulation in peripheral blood mononuclear cells (PBMCs) of PD patients, we further analyzed its expression in PBMCs from 57 PD patients and postmortem striatal tissues, revealing significant upregulation relative to controls. In rotenone (ROT)-induced PD models, elevated ZBTB16 correlated with increased apoptotic activity. Mechanistic investigations in SH-SY5Y dopaminergic neurons and BV2 microglia-like cells (BV2 cells) showed that ZBTB16 overexpression enhanced α-syn expression through transcriptional activation and post-translational modifications, promoting aggregation independent of mutation status. Confocal microscopy confirmed α-syn/SUMO1 colocalization in PD striatal tissues, with microglial models demonstrating ZBTB16-dependent UBC9 upregulation that increased SUMO1+/α-syn+ cells; knockdown reversed this effect. Additionally, in BV2 cells co-expressing mutant LRRK2 and α-syn, ZBTB16 amplified pathogenicity by boosting NLRP3 inflammasome activation, Gasdermin D (GSDMD) expression, and IL-1β/IL-18 secretion, with significant GSDMD/α-syn co-localization in PD tissues. Based on initial RNA sequencing analysis indicating that lnc-USP28-6 regulates ZBTB16 expression, systematic analysis of the ZBTB16 promoter identified lnc-USP28-6. Clinical data identified elevated lnc-USP28-6 in PD peripheral blood, which transcriptionally upregulated ZBTB16 and α-syn in SH-SY5Y cells independently of ROT. These findings unveil a novel lnc-USP28-6/ZBTB16 axis driving PD pathogenesis via dual mechanisms: exacerbating neuroinflammation through inflammasome activation and promoting α-syn aggregation via SUMOylation, indicating promising therapeutic targets.