Neuroprotective potential of phycocyanobilin and C-phycocyanin: from molecular targets to translational applications

Phycocyanobilin (PCB), the covalently bound chromophore of the cyanobacterial protein C-phycocyanin (CPC), is recognized as a bioactive molecule with neuroprotective and anti-inflammatory properties. PCB and CPC, frequently coexisting in Spirulina extracts or experimental formulations, have demonstrated beneficial effects in preclinical models of multiple sclerosis, ischemic stroke, and Alzheimer’s disease. Reported mechanisms include attenuation of oxidative stress, reduction of neuroinflammation, and preservation of mitochondrial function, thereby contributing to a reparative microenvironment within the central nervous system. PCB can be obtained through two complementary approaches: Extraction from cyanobacterial biomass, where it remains covalently bound to CPC, and heterologous biosynthesis in Escherichia coli (E. coli), which enables production of free PCB as a high-purity, scalable linear tetrapyrrole suitable for translational applications. This mini-review summarizes current evidence on the neuroprotective actions of PCB and CPC, highlights their molecular targets, and discusses biotechnological advances that support their potential role in remyelination. By bridging natural pigment pharmacology with recombinant production strategies, PCB is positioned as a multitarget candidate of growing interest for the development of future neuroprotective and neurorepair therapies.