Stearoyl-CoA desaturase-1: a potential therapeutic target for neurological disorders.

Disturbances in the fatty acid lipidome are increasingly recognized as key drivers in the progression of various brain disorders. In this review article, we delve into the impact of Δ9 fatty acid desaturases, with a particular focus on stearoyl-CoA desaturase-1 (SCD1), within the setting of neuroinflammation, neurodegeneration, and brain repair. Over the past years, it was established that inhibition or deficiency of SCD1 not only suppresses neuroinflammation but also protects against neurodegeneration in conditions such as multiple sclerosis, Alzheimer's disease, and Parkinson's disease. This protective effect is achieved through different mechanisms including enhanced remyelination, reversal of synaptic and cognitive impairments, and mitigation of α-synuclein toxicity. Intriguingly, metabolic rerouting of fatty acids via SCD1 improves the pathology associated with X-linked adrenoleukodystrophy, suggesting context-dependent benign and harmful effects of SCD1 inhibition in the brain. Here, we summarize and discuss the cellular and molecular mechanisms underlying both the beneficial and detrimental effects of SCD1 in these neurological disorders. We explore commonalities and distinctions, shedding light on potential therapeutic challenges. Additionally, we touch upon future research directions that promise to deepen our understanding of SCD1 biology in brain disorders and potentially enhance the clinical utility of SCD1 inhibitors.