The critical role of ceramide in mental health and psychiatric diseases.

Ceramides (Cer) are lipid signaling molecules regulating cell proliferation, differentiation, senescence and apoptosis, whose metabolic disturbance disrupts organismal homeostasis. Accumulating evidence links ceramide imbalance to psychiatric and neurodegenerative diseases, yet few systematic reviews summarize subtype-specific ceramide functions. This review outlines ceramide anabolic and catabolic pathways, compares functional distinctions among ceramides with distinct acyl chain lengths, describes substrate preferences of ceramide metabolic enzymes, and introduces ceramide detection techniques. On this basis, we discuss regulatory roles and underlying molecular mechanisms of ceramides in schizophrenia, Alzheimer's disease, epilepsy, depression, bipolar disorder and anxiety disorders, identify disease-specific effects of distinct ceramide subtypes, and provide theoretical evidence for lipid-targeted pharmacological research on psychiatric disorders.