The Anti-Inflammatory Effect of a γ-Lactone Isolated from Ostrich Oil of Struthio camelus (Ratite) and Its Formulated Nano-Emulsion in Formalin-Induced Paw Edema

• Published in: Molecules (Basel, Switzerland) Switzerland), 2021-06, Vol.26 (12), p.3701
• Main Authors: Eltom, Salah E. M., Abdellatif, Ahmed A. H., Maswadeh, Hamzah, Al-Omar, Mohsen S., Abdel-Hafez, Atef A., Mohammed, Hamdoon A., Agabein, Eiman ME, Alqasoomi, Ibrahim, Alrashidi, Salem A., Sajid, Mohammed S. M., Mobark, Mugahid A.
• Format: Article
• Language: English
• Subjects: Contact dermatitis; Diclofenac; Diuretics; Drowsiness; Eczema; Edema; Ibuprofen; Inflammation; Lethargy; methylcellulose; nano-emulsion; Nanoparticles; Natural products; NMR; Nonsteroidal anti-inflammatory drugs; Nuclear magnetic resonance; Oil; Oral administration; Ostrich oil; Particle size; Skin; Skin diseases; Spectrum analysis; Struthio camelus; Surfactants; Toxicity; γ-lactone
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules26123701

The ostrich oil of Struthio camelus (Ratite) found uses in folk medicine as an anti-inflammatory in eczema and contact dermatitis. The anti-inflammatory effect of a γ-lactone (5-hexyl-3H-furan-2-one) isolated from ostrich oil and its formulated nano-emulsion in formalin-induced paw edema was investigated in this study. Ostrich oil was saponified using a standard procedure; the aqueous residue was fractionated, purified, and characterized as γ-lactone (5-hexyl-3H-furan-2-one) through the interpretation of IR, NMR, and MS analyses. The γ-lactone was formulated as nano-emulsion using methylcellulose (MC) for oral solubilized form. The γ-lactone methylcellulose nanoparticles (γ-lactone-MC-NPs) were characterized for their size, shape, and encapsulation efficiency with a uniform size of 300 nm and 59.9% drug content. The γ-lactone was applied topically, while the formulated nanoparticles (NPs) were administered orally to rats. A non-steroidal anti-inflammatory drug (diclofenac gel) was used as a reference drug for topical use and ibuprofen suspension for oral administration. Edema was measured using the plethysmograph method. Both γ-lactone and γ-lactone-MC-NPs showed reduction of formalin-induced paw edema in rats and proved to be better than the reference drugs; diclofenac gel and ibuprofen emulsion. Histological examination of the skin tissue revealed increased skin thickness with subepidermal edema and mixed inflammatory cellular infiltration, which were significantly reduced by the γ-lactone compared to the positive control (p-value = 0.00013). Diuretic and toxicity studies of oral γ-lactone-MC-NPs were performed. No diuretic activity was observed. However, lethargy, drowsiness, and refusal to feeding observed may limit its oral administration.