Title:Nanomedicine and its Application in Treatment of Microglia-mediated Neuroinflammation
VOLUME: 21 ISSUE: 37
Author(s):N. Baby, R. Patnala, Eng-Ang Ling and S.T. Dheen
Affiliation:Department of Anatomy, Yong Loo Lin School of Medicine, National University of Singapore, Blk MD10, 4 Medical Drive, Singapore 117594.
Keywords:Microglia, nano particles, neurodegeneration.
Abstract:Nanomedicine, an emerging therapeutic tool in current medical frontiers, offers targeted drug delivery for many
neurodegenerative disorders. Neuroinflammation, a hallmark of many neurodegenerative disorders, is mediated by microglia,
the resident immunocompetent cells of the central nervous system (CNS). Microglial cells respond to various stimuli
in the CNS resulting in their activation which may have a beneficial or a detrimental effect. In general, the activated microglia
remove damaged neurons and infectious agents by phagocytosis, therefore being neuroprotective. However, their
chronic activation exacerbates neuronal damage through excessive release of proinflammatory cytokines, chemokines and
other inflammatory mediators which contribute to neuroinflammation and subsequent neurodegeneration in the CNS.
Hence, controlling microglial inflammatory response and their proliferation has been considered as an important aspect in
treating neurodegenerative disorders. Regulatory factors that control microglial activation and proliferation also play an
important role in microglia-mediated neuroinflammation and neurotoxicity. Various anti-inflammatory drugs and herbal
compounds have been identified in treating microglia-mediated neuroinflammation in the CNS. However, hurdles in
crossing blood brain barrier (BBB), expression of metabolic enzymes, presence of efflux pumps and several other factors
prevent the entry of these drugs into the CNS. Use of non-degradable delivery systems and microglial activation in response
to the drug delivery system further complicate drug delivery to the CNS. Nanomedicine, a nanoparticle-mediated
drug delivery system, exhibits immense potential to overcome these hurdles in drug delivery to the CNS enabling new alternatives
with significant promises in revolutionising the field of neurodegenerative disease therapy. This review attempts
to summarise various regulatory factors in microglia, existing therapeutic strategies in controlling microglial activation,
and how nanotechnology can serve to improve the delivery of therapeutic drugs across the BBB for treating microglia-
mediated neuroinflammation and neurodegeneration.
