Andrographolide (AG) is the main diterpenoid of Andrographis paniculata (Burm. f.) Wall. ex Nees (Acanthaceae) and it has been reported to exhibit a wide spectrum of biological activities including anti-inflammatory, anticancer, antihyperlipidemic and so on. However it is insoluble in water, it is unstable under alkaline conditions and it is rapidly metabolized in the intestine [1]. In this work nanocochleates (NCs) based on phosphatidylcholine, cholesterol and calcium ions were prepared by trapping method. The multi-layered cylindrical structures of NCs protect the incorporated drug from degradation in hazardous environmental conditions, resulting in enhanced oral bioavailability [2]. Oral administration is characterized by good patient compliance, lower medical expenses and fewer side effects. AG-NCs exhibit an average size of 140 nm with good homogeneity and zeta potential of -22 mV. TEM observations provided details on the morphology: AG-NCs had a cigar-like shape with a regular size distribution which was comparable with Light Scattering data. AG-NCs were freeze dried without cryoprotectant and were stored at room temperature. After 60 days no variations of size, homogeneity and zeta potential were observed. The encapsulation efficiency determined by HPLC-DAD analyses was 71%. In vitro release studies in PBS at pH 7.4 indicated that after 24h approximately 95% of AG was released and Hixson model was shown to be the best-fit model to describe the kinetic of release. In vitro gastrointestinal stability studies were also performed. Finally J77A.1 macrophage cells were cultured to investigate the potential cytotoxicity and uptake of NCs.
References:
[1] Chen LL, Wang ZH. Investigation of basic physical and chemical properties of andrographolide. Pharm Today 2010 ; 20 (1): 41-43.
[2] Asprea M, Leto I, Bergonzi MC, Bilia, AR. Thyme essential oil loaded in nanocochleates: Encapsulation efficiency, in vitro release study and antioxidant activity. LWT-Food Science and Technology 2017; 77 : 497-502.