Improved hepatoprotective activity of silymarin via encapsulation in the novel vesicular nanosystem bilosomes

Anionic versus cationic bilosomes as oral nanocarriers for enhanced delivery of the hydrophilic drug risedronate

Albeit its well known potency as a postmenopausal osteoporosis treatment, Risedronate suffers from poor oral bioavailability and high oral toxicity. This is the first work to assess the potential of bilosomes to address challenges of RS oral delivery. Furthermore, impact of integrating cationic moiety into bilosomes on intestinal digestability and toxicity of RS nanovesicles was first investigated in this article. Prepared formulations were optimized based on physicochemical properties, digestibility, intestinal permeation and local toxicity studies. Optimized preparations were prepared by reversed phase evaporation technique with three extrusion cycles and loaded by 10 mg/ml RS. Molar lipid to bile salt to cholesterol ratio was adjusted to 4:1:1 at pH 5. Addition of cholesterol had significantly improved bilosomes stability to digestive media. Results also revealed that permeation of anionic vesicles increased permeation by 1.5 times more than RS solution and reduced drug toxicity by 2 folds. On the other hand, Cationic bilosomes showed good stability in GIT fluids but their induced oral toxicity could limit their use. In conclusion, bilosomes are superior over liposomes regarding protection of delivery system from the damaging effect of external in digestive bile salts. In addition, it decreases toxicity issues of orally administered drugs.

Application of Spray Drying Particle Engineering to a High-Functionality/Low-Solubility Milk Thistle Extract: Powders Production and Characterization

Many natural compounds having antioxidant and anti-inflammatory activity are a potential target for new therapies against chronic inflammatory syndromes. The oral administration of functional herbal supplements may become a prevention strategy or therapy adjuvant for susceptible patients. A case study is our milk thistle (Silybum marianum) extract rich in silymarin complex. A water-soluble microencapsulated powder system was developed by a spray drying technique to improve the poor silymarin bioactivity after oral administration. Sodium carboxymethylcellulose (NaCMC) was employed as coating/swelling polymer matrix and sodium lauryl sulfate (SLS) as the surfactant (1:1:0.05 w/w/w). A H₂O/EtOH/acetone (50/15/35 v/v/v) solvent system was used as liquid feed. The microsystems were capable of improving the in vitro dissolution and permeation rates, suggesting an enhancement of bioactivity after oral administration. The microsystems protect the antioxidant activity of silymarin after harsh storage conditions period and do not affect the anti-inflammatory properties of the raw extract (efficient already at lower concentrations of 0.312 mg/mL) to reduce dendritic cells (DCs) inflammatory cytokine secretion after lipopolysaccharide administration. This approach allows managing particle size, surface properties and release of bioactive agents improving the bioactivity of a herbal supplement and is also possibly applicable to many other similar natural products.

Formulation and evaluation of pH-sensitive rutin nanospheres against colon carcinoma using HCT-116 cell line

The objective of this study was to target rutin, in a more solubilized form, to the colon aiming at treatment of colon carcinoma. pH sensitive nanospheres were prepared by the nanoprecipitation technique employing Eudragit S100. Different drug: polymer ratios as well as different concentrations of the stabilizer Poloxamer-188 were used. The developed rutin nanospheres exhibited entrapment efficiency ranging from 94.19% to 98.1%, with a zeta potential values <−20 mV. They were spherical in shape and their sizes were in the nanometric dimensions. The in vitro release study of nanospheres formulations revealed enhancement of aqueous solubility of rutin and indicated drug targeting to the colon. The selected formulations were stable after storage for 6 months at ambient room and refrigeration temperatures. In vitro cytotoxic study was conducted on human colon cancer (HCT-116) as well as normal human fibroblasts (BHK) cell lines, employing Sulphorhodamine-B assay. Rutin nanospheres showed significantly (P = .001) higher area under inhibition percentage curve, when compared to free drug, revealing more than 2-fold increase in rutin cytotoxic activity. These results reveal that Eudragit S100 nanospheres could be a potential drug delivery system to the colon with enhanced solubility and hence improved the cytotoxic activity of rutin.