Inhibitory effect of a new orally active cedrol-loaded nanostructured lipid carrier on compound 48/80-induced mast cell degranulation and anaphylactic shock in mice.

BACKGROUND: Type I hypersensitivity is an allergic reaction characterized by the overactivity of the immune system provoked by normally harmless substances. Glucocorticoids, anti-histamines, or mast cell stabilizers are the choices of treatment for type I hypersensitivity. Even though these drugs have the anti-allergic effect, they can have several side effects in prolong use. Cedrol is the main bioactive compound of Cedrus atlantica with anti-tumor, anti-oxidative, and platelet-activating factor inhibiting properties. METHODS: In this study, the preparation and anti-anaphylactic effect of cedrol-loaded nanostructured lipid carriers (NLCs) were evaluated. NLCs were prepared using Compritol® 888 ATO and triolein as lipid phase and vitamin E d-α-tocopherylpolyethyleneglycol 1000 succinate, soya lecithin, and sodium deoxycholate as nanoparticle stabilizers. RESULTS: The average diameter of cedrol-NLCs (CR-NLCs) was 71.2 nm (NLC-C1) and 91.93 nm (NLC-C2). The particle had negative zeta potential values of -31.9 mV (NLC-C1) and -44.5 mV (NLC-C2). Type I anaphylactoid reaction in the animal model is significantly reduced by cedrol and cedrol-NLC. This in vivo activity of cedrol resulted that cedrol suppressed compound 48/80-induced peritoneal mast cell degranulation and histamine release from mast cells. Furthermore, compound 48/80-evoked Ca2+ uptake into mast cells was reduced in a dose-dependent manner by cedrol and cedrol-NLC. Studies confirmed that the inhibition of type I anaphylactoid response in vivo in mice and compound 48/80-induced mast cell activation in vitro are greatly enhanced by the loading of cedrol into the NLCs. The safety of cedrol and CR-NLC was evaluated as selectivity index (SI) with prednisolone and cromolyn sodium as positive control. SI of CR-NLC-C2 was found to be 11.5-fold greater than both prednisolone and cromolyn sodium. CONCLUSION: Administration of CR-NLC 24 hours before the onset of anaphylaxis can prevent an anaphylactoid reaction. NLCs could be a promising vehicle for the oral delivery of cedrol to protect anaphylactic reactions.

Development and evaluation of a cedrol-loaded nanostructured lipid carrier system for in vitro and in vivo susceptibilities of wild and drug resistant Leishmania donovani amastigotes.

Leishmaniasis is an epidemic in various countries, and the parasite Leishmania donovani is developing resistance against available drugs. In the present study the antileishmanial action of cedrol was evaluated in vitro and in vivo. Activity potentiation was achieved via nanostructured lipid carrier (NLC) complexation of cedrol. Cedrol-loaded NLC was prepared through the hot-melting emulsification-ultrasonication method. The cedrol- NLC prepared did not require the use of any organic solvents. The characterization of NLC-C1 and NLC-C2 revealed that particle size was 46.62nm and 54.73nm for 3.85%, and 7.48% drug loading, respectively and negative charge of -19.2mV and -23.7mV. The cedrol-loaded NLC were found to be spherical with a smooth surface. Drug-carrier interactions were clearly visualized in FT-IR studies. Incorporation of cedrol in NLC was ascertained in DSC and XRD analysis. Antileishmanial activities of free cedrol and cedrol-NLC were performed against L. donovani wild-type, sodium stibogluconate, paromomycin and field isolated resistant strains in axenic amastigotes and amastigotes in macrophage model. Coumarin-6 loaded NLC nanoparticles were assessed for macrophage internalization in confocal microscopic studies. Cedrol showed significant antileishmanial activity in wild-type (IC50=1.5µM), sodium stibogluconate resistant (IC50=2µM), paromomycin resistant (IC50=1.8µM) and field isolated resistant (IC50=1.35µM) strains in macrophage together with cytotoxicity (CC50=74µM) in mouse peritoneal macrophage cells. Incorporation of cedrol in NLC-C2 resulted in 2.1-fold and 2-fold increase in selectivity indexes (CC50/IC50) for wild-type and drug resistant strains, respectively. In addition, in vivo studies revealed that bioactivity of NLC-C2 were 2.3 to 3.8-fold increased in wild-type and 3 to 4.9-fold increased in drug resistant strains when compared with free cedrol; administered orally in mouse leishmaniasis model. Overall, NLC-C2 showed superior antileishmanial activity to free cedrol and miltefosine in oral dose. These findings support the use of NLCs for oral delivery of poorly water-soluble antileishmanial drugs in treatment of leishmaniasis. CHEMICAL COMPOUNDS: Cedrol (PubChem CID: 65575); Compritol® 888 ATO (PubChem CID: 62726); Triolein (PubChem CID: 5497163); Pluronic F68 (PubChem CID: 24751); Soya lecithin (PubChem CID: 57369748); Sodium deoxycholate (PubChem CID: 23668196); Miltefosine (PubChem CID: 3599); Paromomycin (PubChem CID: 165580); Amphotericin B (PubChem CID: 5280965); Sodium stibogluconate (PubChem CID: 16683012).

Oleanolic acid loaded poly lactic co- glycolic acid- vitamin E TPGS nanoparticles for the treatment of Leishmania donovani infected visceral leishmaniasis.

Oleanolic acid (OA) has low aqueous solubility and low permeability, which results poor bioavailability. To surmount the inadequacy, our aim was to fabricate oleanolic acid loaded poly lactic co- glycolic acid (PLGA)- d-α- tocopheryl polyethylene glycol 1000 succinate (TPGS) nanoparticles, which could be efficacious for the treatment of Leishmania donovani mediated visceral leishmaniasis (VL). OA loaded PLGA- TPGS nanoparticles were prepared by emulsion solvent evaporation technique. Cellular uptake was investigated. In vitro cumulative drug release study was carried out. In vitro susceptibility was confirmed against the amastigotes of Leishmania donovani AG83 wild and drug resistant strains. In vivo antileishmanial activity was evaluated against wild type amastigotes of L. donovani. OA loaded nanoparticles were successfully formulated. The highest drug loading was found to be 11.08%±0.35%. 85.66%±0.56% was the highest in vitro OA release for 30days among the formulations. In vivo study revealed that, 98.82±1.92% amastigote burden in spleen of BALB/c mice were suppressed by the polymeric nanoformulation of OA. Experimental OA nanoparticle formulation proved itself as an attractive carrier for OA which was significantly efficacious against both in vitro and in vivo amastigote form of Leishmania donovani than pure OA for chemotherapeutic intervention of visceral leishmaniasis.

Immuno-modulation effect of sulphated polysaccharide (porphyran) from Porphyra vietnamensis.

Our investigation explores the immuno-efficiency of sulphated polysaccharides enriched Porphyra vietnamenis. Isolated polysaccharide fraction (17.1-25.8%) was characterized by FTIR and NMR spectroscopy which showed the presence of typical linear backbone structure called as porphyran. Oral administration of porphyran (200-500 mg/kg) evoked a significant (P ≤ 0.05) increase in weight of the thymus, spleen and lymphoid organ cellularity. The total leucocyte and lymphocyte count was increased significantly (P<0.005). The increase in the percent neutrophil adhesion to nylon fibres as well as a dose-dependent increase in antibody titre values was observed. A decreased response to DTH reaction induced by SRBC was recorded. A potential phagocytic response was seen and significant changes were observed in the formation of formazone crystals. It also prevented myelosuppression in cyclophosphamide drug treated rats. The results indicated that P. vietnamenis possesses potential immunomodulatory activity and has therapeutic potential for the prevention of autoimmune diseases.