Unconventional Small Molecule MNP-021 Protects Neuronal and Glial Function from Diabetes-Associated Glucotoxicity and Neuroinflammation

Abstract Background Diabetes-associated neurodegeneration is amplified by methylglyoxal (MGO)-driven dicarbonyl stress linking hyperglycemia to neuronal insulin resistance and maladaptive neuroinflammation. We tested the neuroprotective activity of MNP-021, a non-electrophilic TRPA1 modulator, in neurons and glial cells in vitro . Methods SH-SY5Y neurons were pretreated with MNP-021 and challenged with MGO, then profiled by high-content imaging, RNA-seq, Seahorse OCR/ECAR, glycolytic stress assays and AKT/ERK/CREB immunoblotting ± insulin. In parallel, HMC3 glial cells were treated with MNP-021, exposed to LPS/TNF-α or Aβ (25–35) and tested for viability and inflammatory markers by ELISA and qRT-PCR. Results MGO increased nucleus-to-cytoplasm area ratio by 49% and dysregulated glucose handling, increasing 2-NBDG uptake by ∼25%, with GLUT1/GLUT4 membrane redistribution; MNP-021 normalized morphology, uptake, and transporter localization without cytotoxicity up to 10 µM. RNA-seq identified 754 MGO-deregulated genes, including ISR/metabolic nodes (GCK, SESN2, PHGDH/PSAT1, PCK2); MNP-021 buffered stress-induced transcription with limited baseline effects, remodeled mitochondrial redox readouts consistent with controlled ROS signaling, while improving mitochondrial content/architecture and blunting stress-evoked compensatory glycolysis. MNP-021 restored pro-survival signaling (pAKT/pERK and nuclear pCREB), including insulin responsiveness during MGO exposure. MNP-021 reduced IL-6/TNF-α release while increasing IL-10 and ARG1 (∼1.9-fold vs LPS/TNF-α) in HMC3 glial cells, shifting them toward a pro-resolving IL-10/ARG1 program with reduced Aβ (25–35)- evoked cytokine release with GLP-1 remaining very low (≤10 pg/mL) and not significantly increased in this system. Conclusions MNP-021 coordinates transcriptomic restraint, transporter-level glucose handling, mitochondrial resilience, and pro-survival/pro-resolving signaling across neuron–microglia compartments, supporting TRPA1-tuned small-molecule modulation as a candidate strategy against dicarbonyl-linked neuro-metabolic stress.