Protective effects of SA-31 in a psychostimulant-induced neurotoxicity model using SH-SY5Y cells
Charles E Amankwa1, Biddut DebNath1, Arlene Abraham2
1Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA.
Background:
Cocaine- and methamphetamine (METH)-induced mitochondrial dysfunction and oxidative stress are key contributors to the neuropathology of psychostimulant addiction. These effects are often accompanied by epigenetic alterations, mitochondrial damage, and the accumulation of reactive oxygen species (ROS). Methionine synthase (MS) plays a critical role in epigenetic regulation and neuronal survival and may offer neuroprotection against psychostimulant-induced toxicity. We hypothesize that SA-31, a novel thiourea-based analog of TEMPOL, will attenuate cocaine or METH induced decrease in antioxidant, anti-inflammatory, and MS activities in neuronal cells.
Methods:
SA-31 was synthesized and characterized via 1H NMR and mass spectrometry. Human SH-SY5Y dopaminergic neural cells were exposed to tert‑butyl hydrogen peroxide (TBHP), cocaine hydrochloride, or methamphetamine (METH), with or without co-treatment with SA-31 for 24 h. Cell viability was measured using MTT assays. MS activity, IL-1β, superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase levels were assessed via ELISA. Mitochondrial function was evaluated using Seahorse-based oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) assays.
Results:
SA-31 (10-100 µM) significantly protected cells from TBHP-, cocaine-, and METH-induced cytotoxicity. TBHP and METH reduced MS activity, which was significantly restored by SA-31. The compound also reversed cocaine-induced reductions in SOD, GPx, and catalase and lowered pro-inflammatory IL-1β levels. Additionally, SA-31 (1-100 µM) enhanced mitochondrial respiration and glycolytic activity.
Conclusion:
These findings suggest that SA-31 confers neuroprotection by enhancing MS activity, upregulating antioxidant defenses, and improving mitochondrial function. Further studies in rodent models of addiction are planned to evaluate its therapeutic potential for psychostimulant use disorders and related neurodegenerative conditions.
