Journal of Glycobiology
Open Access

Role and Functions of Polysialic Acid in Neural Development and Plasticity

Sangeeta Sharma^{* *}Correspondence: Sangeeta Sharma, Department of Biomedical Sciences, School of Biosciences and Technology, Vellore Institute of Technology, Vellore, India, Email:

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Description

Polysialic Acid (PSA) is a unique glycan consisting of long chains of repeating units of the sialic acid molecule, which is also known as N-acetylneuraminic acid. This glycan is primarily found on the cell surface of certain types of cells in vertebrates, including neurons and immune cells, and has been implicated in a variety of cellular processes and diseases.

The discovery of PSA dates back to the 1960s, when it was first identified as a component of a polysaccharide fraction isolated from human brain tissue. Since then, its presence and functions have been extensively studied, and research has shown that PSA is involved in a variety of biological processes, including cell-cell interactions, cell migration, and the regulation of neural plasticity.

One of the well-studied functions of PSA is its role in neural development and plasticity. During development, PSA is highly expressed in the nervous system, particularly in regions involved in learning and memory, such as the hippocampus. PSA has been shown to play a critical role in neuronal migration and axonal pathfinding, and it is also involved in the regulation of synaptic plasticity and the formation and maintenance of long-term memories.

In addition to its role in neural development, PSA has also been implicated in a variety of neurological diseases. For example, changes in PSA expression have been observed in several neurodegenerative disorders, including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. In these diseases, alterations in PSA expression may contribute to disease progression by affecting neuronal survival, plasticity, and function.

PSA has also been shown to play a role in the immune system. Specifically, PSA is expressed on the surface of certain immune cells, including B cells and dendritic cells, where it is thought to be involved in cell-cell interactions and the regulation of immune responses. For example, PSA on B cells has been shown to regulate B cell migration and maturation, and PSA on dendritic cells has been shown to modulate T cell activation and differentiation.

The functions of PSA in both the nervous system and the immune system suggest that this glycan may be involved in the interaction between these two systems. Indeed, recent research has suggested that there may be a link between the immune system and certain neurological disorders, such as autism and schizophrenia. It is possible that alterations in PSA expression or function may contribute to the development of these disorders by disrupting the communication between the nervous and immune systems.

Despite many functions of PSA that have been identified, much remains to be learned about this glycan. One area of research that is particularly promising is the use of PSA as a therapeutic target in cancer. PSA has been shown to be overexpressed in several types of cancer, including glioma, neuroblastoma and small cell lung cancer. Targeting PSA in these cancers may be an effective approach to treatment, as it could disrupt the interactions between cancer cells and their environment, inhibit cell migration and invasion, and sensitize cancer cells to chemotherapy and radiation therapy.

Another area of research that is currently being explored is the use of PSA as a biomarker for disease. Changes in PSA expression have been observed in several diseases, as mentioned above, and measuring PSA levels in blood or cerebrospinal fluid may be a useful diagnostic tool. For example, PSA levels have been shown to be elevated in patients with multiple sclerosis, and measuring PSA levels may help to diagnose the disease and monitor disease progression.

Conclusion

In conclusion, polysialic acid is a unique glycan with a variety of functions in the nervous and immune systems. Its involvement in neural development and plasticity, as well as its potential as a therapeutic target in cancer, make it an area of active research. Further investigation into the functions and mechanisms of PSA may lead to new treatments.