The role of AI-assisted drug repurposing in neurological disorders: a systematic review of validation strategies, challenges and opportunities.

Neurological disorders refer to a diverse group of conditions that affect the brain, peripheral nerves, and spinal cord and impair socioemotional, cognitive, motor, and sensory functions. Alzheimer's disease (AD), Multiple Sclerosis (MS), Parkinson's disease (PD), Huntington's disease (HD), and Amyotrophic Lateral Sclerosis (ALS) are some of the well-known neurodegenerative diseases that affect millions of people worldwide. Despite the advanced technologies and nano-drug delivery systems, the success rate of developing drugs for neurological disorders is significantly low. Among several constraints, including gastrointestinal irritation, rapid metabolism, and low stability, the blood-brain barrier (BBB) emerges as one of the key challenges in the development and application of drugs against neurological disorders. These challenges necessitate innovative approaches to develop cost-effective therapeutic strategies. Drug repurposing, the discovery of new therapeutic benefits of existing drugs, is a promising drug discovery approach for discovering potential treatment options for complex neurological disorders. This review aims to explore the advanced and significant progress in drug repurposing for major neurological disorders, including MS, AD, PD, ALS, HD, stroke, and neuropsychiatric conditions. It places an explicit emphasis on discussing the potential role of artificial intelligence (AI)-assisted drug repurposing and understanding of the biological mechanisms in discovering new drugs for these neurological conditions. This also examines current challenges in drug repurposing and provides a critical review of the available opportunities and limitations in AI-assisted drug repurposing.