Formulation and optimization of Dryopteris cochleata extract-laden liposomes for immunostimulant activity in rats: in vitro and in vivo evaluation.

Abstract

Objective: This study sought to develop Dryopteris cochleata (DC) extract encapsulated liposomes and their characterization in order to increase its immunomodulatory activity.

Significance: The significance of DC extract-laden liposomes is to improve their immunostimulant activity. Thus, this technology offers a novel immunotherapeutic strategy to combat a range of diseases.

Methods: DC extract was obtained using supercritical fluid extraction and screened for acute oral toxicity in Wistar rats. The extract-laden liposomes were optimized by Box-Behnken Design (BBD) and were evaluated for different in vitro parameters. Moreover, extract and liposomes were investigated for immunomodulatory activity in Wistar albino rats.

Results: The extract was found to be safe in Wistar rats at a dose of 2000 mg/kg. The optimized liposomes fabricated with phosphatidylcholine (4.5 mg) and cholesterol (3.1 mg), and probe cycle number of 56.5, displayed particle size of 147.5 ± 8 nm and PDI of 0.239 ± 0.03, respectively. The liposomes exhibited zeta potential of -27.6 ± 4.6 mV and spherical morphology. The Fourier transformed infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) revealed compatibility and thermal stability of the formulation components. Moreover, Powder X-ray diffraction (PXRD) studies signify the amorphous nature of extract following incorporation into liposomes. The antioxidant activity of extract and liposome was observed to be similar to ascorbic acid. Furthermore, significant phagocytic index was shown by both extract and liposome in rats, revealing their potent immunostimulant activity.

Conclusions: Thus, DC extract-laden liposomes may serve as a promising immunostimulant, particularly in recurrent infections, immunodeficiencies, and recovery from chronic illness.