Decoding the PI3K/Akt/mTOR-JAK/STAT signaling axis in multiple sclerosis: mechanistic crosstalk and therapeutic opportunities.

Multiple Sclerosis (MS) is a chronic immune-mediated neurodegenerative disorder characterized by demyelination, axonal injury, and progressive neurological dysfunction. Emerging evidence identifies the phosphoinositide-3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K/Akt/mTOR) and Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathways as interconnected regulators of neuroinflammation and immune dysregulation in MS. This review critically examines the mechanistic crosstalk between these signaling networks and their contribution to disease progression. Dysregulated PI3K/Akt/mTOR signaling influences T-cell activation, immunometabolic reprogramming, autophagy, and oligodendrocyte survival, whereas aberrant activation of the JAK2/STAT3 axis promotes Th17-cell differentiation, cytokine amplification, and sustained inflammatory responses within the central nervous system. Importantly, convergence between Th17/STAT3 signaling and PI3K/Akt-mediated metabolic pathways establishes a regulatory network that enhances microglial activation, blood-brain barrier disruption, and neuronal injury. The review further highlights the context-dependent role of mTOR signaling, which may simultaneously support remyelination and oligodendrocyte maturation while contributing to neurodegeneration when excessively activated. In addition to immune-cell-mediated mechanisms, emerging evidence demonstrates critical contributions of neuronal, glial, endothelial, and oligodendrocyte precursor cell signaling to MS pathology. Preclinical and clinical findings indicate that pharmacological modulation of these pathways can attenuate inflammatory responses and improve neuroprotection; however, therapeutic translation remains challenging because of their dual physiological and pathological functions. Collectively, this review provides an integrated perspective on PI3K/Akt/mTOR-JAK/STAT signaling interactions and highlights cell-specific molecular targets that may facilitate the development of more precise therapeutic strategies for MS.