Poly-ε-Caprolactone Microsphere Polymers Containing Usnic Acid: Acute Toxicity and Anti-Inflammatory Activity

Jéssica A. P. Barbosa, Eryvelton S. Franco, Camilla V. N. S. Silva, Tatiane O. Bezerra, Carlson Carvalho Junior, Marllon A. N. Santana, Teresinha Gonçalves da Silva, Noemia P. S. Santos, Maria Bernadete Sousa Maia

Research output: Contribution to journalArticlepeer-review


Usnic acid (UA) has been studied by its pharmacological properties; however, it presents moderate toxicity, low solubility, and absorption by biological membranes. The aim of this study was to develop poly-ε-caprolactone microsphere polymers containing UA (UA-micro) and evaluate their acute toxicity and anti-inflammatory activity. The microspheres were prepared by multiple emulsion technique (water/oil/water) and characterized by the encapsulation efficiency, particle size, polydispersity index, and zeta potential. The acute toxicity of UA and UA-micro (25–50 mg/kg; p.o.) was evaluated in mice. The anti-inflammatory activity of UA and UA-micro was evaluated by subcutaneous air pouch and carrageenan-induced paw edema in rat, with measurement of inflammatory cytokines and MPO levels. The UA presented encapsulation efficiency of 97.72%, particle size of 13.54 micrometers, polydispersity index of 2.36, and zeta potential of 44.5 ± 2.95 mV. The UA-micro presented lower acute toxicity (LD50 value up to 2000 mg/kg; p.o.) when compared to UA. UA-micro and UA (25 mg/kg) significantly reduced paw volume and decreased MPO levels, whereas only UA-micro (50 mg/kg) reduced significantly IL-1β, TNF-α, and NO levels in inflammatory exudate. These results suggest that controlled release systems, as microspheres, can be a promising alternative to reduce the toxicity of UA, making it a viable compound for inflammation therapy.
Original languageEnglish
Article number7392891
Pages (from-to)1-9
Number of pages9
JournalEvidence-Based Complementary and Alternative Medicine
Publication statusPublished - 4 Dec 2017


Dive into the research topics of 'Poly-ε-Caprolactone Microsphere Polymers Containing Usnic Acid: Acute Toxicity and Anti-Inflammatory Activity'. Together they form a unique fingerprint.

Cite this