The AAPS Journal

, 20:18 | Cite as

Therapeutic Delivery of Simvastatin Loaded in PLA-PEG Polymersomes Resulted in Amplification of Anti-inflammatory Effects in Activated Microglia

  • Dharani Manickavasagam
  • Kimberly Novak
  • Moses O. OyewumiEmail author
Research Article


Simvastatin (Sim), a lipid-lowering drug has been studied in chronic neuroinflammation associated with degenerative brain disorders due to its potential protective properties against inflammatory reaction, oxidative damage, neuronal dysfunction, and death. Meanwhile, potential application of Sim in neuroinflammation will require a suitable delivery system that can overcome notable challenges pertaining to poor blood–brain barrier (BBB) permeability and side/off-target effects. Herein, we engineered and characterized nano-sized polymersomes loaded with Sim (Sim-Ps) using PEG-PdLLA (methoxy polyethylene glycol-poly(d,l) lactic acid) diblock co-polymers. Studies in BV2 microglia indicated that Sim-Ps was superior to Sim alone in suppressing nitric oxide (NO) and proinflammatory cytokines (interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) secretion against LPS activation. The effectiveness of Sim-Ps as compared with Sim alone, in attenuating NO and cytokine production by activated BV2 cells can be attributed to (a) colloidal stability of the delivery platform, (b) protracted release of biologically active Sim, and (c) particulate internalization coupled with enhanced Sim exposure to BV2 cells. Intranasal delivery in BALB/c mice demonstrated enhanced brain distribution with increasing time after administration. Overall data demonstrated suitability of PEG-PdLLA polymersomes in Sim delivery for potential application in treating neuroinflammation.

Key Words

inflammation microglia neuroprotection polymersomes simvastatin 


Funding Information

The research was supported by a grant from the College of Pharmacy, NEOMED priority project fund to MOO.

Compliance with Ethical Standards

Conflict Interest

The authors declare that they have no conflict of interest.


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Copyright information

© American Association of Pharmaceutical Scientists 2017

Authors and Affiliations

  1. 1.Department of Biomedical SciencesKent State UniversityKentUSA
  2. 2.Department of Pharmaceutical Sciences, College of PharmacyNortheast Ohio Medical UniversityRootstownUSA

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