Pharmacokinetic interaction potential assessment of cladrin, a potent bioactive constituent of Butea monosperma, and raloxifene, a prescription anti-osteoporotic by in vitro ADME approach

Raloxifene is a well-known modulator of estrogen receptors which is structurally similar to tamoxifen. As flavonoids can interact with the estrogen modulator raloxifene in vitro, we performed an in vitro stability study and in situ permeability assay of raloxifene and cladrin in female Sprague-Dawley rats when administered alone and when co-administered. The in vitro study samples were analyzed by HPLC; raloxifene administered individually and in combination with cladrin was compared. In this study, we investigated the absorption, metabolic stability, plasma stability, determination of permeability and plasma protein binding of both drugs in SD rats using an established in situ single pass intestinal perfusion model. Increase in the bioavailability of raloxifene and cladrin alone or in co-administration also could be because of the activation of P-glycoprotein in the rat intestine. Further the present report concludes on the basis of ATPase assay of both raloxifene and cladrin alone and in combination showed that both drugs are P-gp substrate. In in situ permeability assay showed that the both drugs competitively lower the permeability of each other but still the predicted human permeability value lied in the range of high permeability drug.

Targeted chemotherapy of visceral leishmaniasis by lactoferrin-appended amphotericin B-loaded nanoreservoir: in vitro and in vivo studies

Aim: Exploitation of lactoferrin-appended amphotericin B bearing nanoreservoir (LcfPGNP-AmB) for targeted eradication of Leishmania donovani. Materials and Methods: LcfPGNP-AmB was architechtured through ionic adsorption of lactoferrin over core poly (d,l-lactide-co-glycolide) nanoparticles and characterized. Anti-Leishmania activity in visceral leishmaniasis models, immunomodulatory potential, biodistribution and toxicity profile were also assessed. Results: LcfPGNP-AmB (size, 196.0 ± 5.28 nm; zeta-potential, +21.7 ± 1.52 mV; encapsulation efficiency, ∼89%) showed reduced toxicity, increased protective proinflammatory mediators expression and down-regulation of disease-promoting cytokines. Biodistribution study illustrated preferential accumulation of LcfPGNP-AmB in liver and spleen. LcfPGNP-AmB showed augmented antileishmanial activity by significantly reducing (∼88%) splenic parasite burden of infected hamsters, compared with commercial-formulations. Conclusion: Superior efficacy, desired stability and reliable safety of cost-effective LcfPGNP-AmB, suggest its potential for leishmaniasis therapeutics

Overexpressed macrophage mannose receptor targeted nanocapsules-mediated cargo delivery approach for eradication of resident parasite: in vitro and in vivo studies

Purpose: Since, Leishmania protozoans are obligate intracellular parasites of macrophages, an immunopotentiating macrophage-specific Amphotericin B (AB) delivery system would be ideally appropriate to increase its superiority for leishmaniasis treatment and to eliminate undesirable toxicity. Herein, we report AB entrapped mannose grafted chitosan nanocapsules (MnosCNc-AB) that results in effective treatment of visceral leishmaniasis, while also enhancing L. donovani specific T-cell immune responses in infected host. Methods: MnosCNc-AB were prepared via synthesized mannosylated chitosan deposition on interface of oil/water nanoemulsion intermediate and were characterized. J774A.1 macrophage uptake potential, antileishmanial activity and immunomodulatory profile were evaluated in hamster. Tissue localization, biodistribution and toxicity profile were also investigated. Results: MnosCNc-AB had nanometric size (197.8 ± 8.84 nm), unimodal distribution (0.115 ± 0.04), positive zeta potential (+31.7 ± 1.03 mV) and 97.5 ± 1.13% cargo encapsulation efficiency. Superior macrophage internalization of mannosylated chitosan nanocapsules compared to unmodified chitosan nanocapsules was observed by fluorescence-based assessment, further confirmed by rapid blood clearance and, greater localization and higher accumulation in macrophage rich liver and spleen. While, MnosCNc-AB mediated cargo distribution to kidney decreased. Augmented in vitro antileishmanial activity and in vivo pro-inflammatory mediator’s expression were observed with MnosCNc-AB, led to significant reduction (∼90%) in splenic parasite burden. Conclusions: Results demonstrated that mannose ligand grafted chitosan nanocapsules could improve selective delivery of AB into macrophages via interactions with overexpressed mannose receptors thus reduce undesirable toxicity. Study provides evidence for MnosCNc-AB potential to leishmaniasis therapeutics and presents valuable therapeutic strategies for combating chronic macrophage-resident microbial infections

Th-1 biased immunomodulation and synergistic antileishmanial activity of stable cationic lipid–polymer hybrid nanoparticle: biodistribution and toxicity assessment of encapsulated amphotericin B

To address issues related to Amphotericin B (AmpB) clinical applications, we developed macrophage targeted cationic stearylamine lipid–polymer hybrid nanoparticles (LPNPs) with complementary characteristics of both polymeric nanoparticles and liposomes, for enhancement of therapeutic efficacy and diminishing toxic effect of encapsulated AmpB. The LPNPs (size 198.3 ± 3.52 nm, PDI 0.135 ± 0.03, zeta potential +31.6 ± 1.91 mV) provide core-shell type structure which has the ability to encapsulate amphiphilic AmpB in higher amount (Encapsulation efficiency 96.1 ± 2.01%), sustain drug release and stabilize formulation tremendously. Attenuated erythrocytes and J774A.1 toxicity of LPNPs demonstrated safe applicability for parenteral administration. Elevated macrophage uptake of LPNPs, rapid plasma clearance and higher drug allocation in macrophage abundant liver and spleen illustrated admirable antileishmanial efficacy of AmpB-LPNPs in vitro (IC50, 0.16 ± 0.04 μg AmpB/ml) and in vivo (89.41 ± 3.58% parasite inhibition) against visceral leishmaniasis models. Augmentation in antileishmanial activity due to Th-1 biased immune-alteration mediated by drug-free LPNPs which elevated microbicidal mediators of macrophages. Moreover, minimal distribution to kidney tissues and low level of nephrotoxicity markers (creatinine and BUN) demonstrated the safety profile of AmpB-LPNPs. Conclusively, reliable safety and macrophage directed therapeutic performance of AmpB-LPNPs suggest it as promising alternative to commercial AmpB-formulations for the eradication of intra-macrophage diseases

Chitosan-assisted immunotherapy for intervention of experimental leishmaniasis via amphotericin B-loaded solid lipid nanoparticles

Solid lipid nanoparticles (SLNs) have emerged as an excellent substitute over polymeric nanoparticles and, when incorporated with chitosan which activates the macrophage to impart an immune response, produce excellent results to fight against deleterious diseases like leishmaniasis where its parasite diminishes the immunity of the host to induce resistance. Based upon this hypothesis, chitosan-coated SLNs were developed and loaded with amphotericin B (AmB) for immunoadjuvant chemotherapy of Leishmania infection. Both uncoated and chitosan-coated AmB-loaded SLNs (AmB-SLNs) were fabricated using solvent emulsification and evaporation method. The various processes and formulation parameters involved in AmB-SLN preparation were optimized with respect to particle size and stability of the particles. In vitro hemolytic test credited the formulations to be safe when injected in the veins. The cellular uptake analysis demonstrated that the chitosan-coated AmB-SLN was more efficiently internalized into the J774A.1 cells. The in vitro antileishmanial activity revealed their high potency against Leishmania-infected cells in which chitosan-coated AmB-SLNs were distinguishedly efficacious over commercial formulations (AmBisome and Fungizone). An in vitro cytokine estimation study revealed that chitosan-coated AmB-SLNs activated the macrophages to impart a specific immune response through enhanced production of TNF-α and IL-12 with respect to normal control. Furthermore, cytotoxic studies in macrophages and acute toxicity studies in mice evidenced the better safety profile of developed formulation in comparison to marketed formulations. This study indicates that the AmB-SLNs are a safe and efficacious drug delivery system which promises strong competence in antileishmanial chemotherapy and immunotherapy

Immunoadjuvant chemotherapy of visceral leishmaniasis in hamsters using amphotericin B-encapsulated nanoemulsion template-based chitosan nanocapsules

The accessible treatment options for life-threatening neglected visceral leishmaniasis (VL) disease have problems with efficacy, stability, adverse effects, and cost, making treatment a complex issue. Here we formulated nanometric amphotericin B (AmB)-encapsulated chitosan nanocapsules (CNC-AmB) using a polymer deposition technique mediated by nanoemulsion template fabrication. CNC-AmB exhibited good steric stability in vitro, where the chitosan content was found to be efficient at preventing destabilization in the presence of protein and Ca2+. A toxicity study on the model cell line J774A and erythrocytes revealed that CNC-AmB was less toxic than commercialized AmB formulations such as Fungizone and AmBisome. The results of in vitro (macrophage-amastigote system; 50% inhibitory concentration [IC50], 0.19 ± 0.04 μg AmB/ml) and in vivo (Leishmania donovani-infected hamsters; 86.1% ± 2.08% parasite inhibition) experiments in conjunction with effective internalization by macrophages illustrated the efficacy of CNC-AmB at augmenting antileishmanial properties. Quantitative mRNA analysis by real-time PCR (RT-PCR) showed that the improved effect was synergized with the upregulation of tumor necrosis factor alpha (TNF-α), interleukin-12 (IL-12), and inducible nitric oxide synthase and with the downregulation of transforming growth factor β (TGF-β), IL-10, and IL-4. These research findings suggest that a cost-effective CNC-AmB immunoadjuvant chemotherapeutic delivery system could be a viable alternative to the current high-cost commercial lipid-based formulations

Chondroitin nanocapsules enhanced doxorubicin induced apoptosis against leishmaniasis via Th1 immune response

Current leishmaniasis treatment is strangled due to concealed residence of parasite and reduced host cell mediated immune response. To circumvent above challenges, novel macrophage targeted oily core polymeric shell based doxorubicin (DOX) loaded nanocapsules (NCAPs) were fabricated employing chondroitin sulphate (CHD) for complimentary immunotherapy coupled chemotherapy against leishmaniasis. Excellent encapsulation efficiency along with pH dependent drug release was demonstrated by NCAPs. Improved cell cycle arrest at G1-S phase (1.56 folds) and apoptosis against promastigotes (6.26 folds), support the remarkable in-vitro antileishmanial activity of NCAPs (IC50: 0.254 ± 0.038 μg/ml) compared to free DOX (IC50: 0.543 ± 0.012 μg/ml). In-vivo antileishmanial activity in hamsters represented a significantly enhanced parasitic inhibition by NCAPs (1.42 folds). Improved activity was mediated via immunotherapeutic activity of NCAPs which up-regulated Th1 immune response (IL-12, INF-γ, and TNF-α) and down-regulated Th2 immune response (IL-4, IL-10, and TGF-β). In conclusion, current novel nano-formulation could be a viable option against leishmaniasis

Bioinspired calcium phosphate nanoparticles featuring as efficient carrier and prompter for macrophage intervention in experimental leishmaniasis

Purpose: To develop a biocompatible and bioresorbable calcium phosphate (CaP) nanoparticles (NPs) bearing Amphotericin B (AmB) with an aim to provide macrophage specific targeting in visceral leishmaniasis (VL). Materials & Methods: CaP-AmB-NPs were architectured through emulsion precipitation method. The developed formulation was extensively characterized for various parameters including in-vitro and in-vivo antileishmanial activity. Moreover, plasma pharmacokinetics, tissue biodistribution and toxicity profile were also assessed. Results: Optimized CaP-AmB-NPs exhibited higher entrapment (71.1 ± 6.68%) of AmB. No trend related to higher hemolysis was apparent in the developed formulation as evidenced in commercially available colloidal and liposomal formulations. Cellular uptake of the developed CaP-AmB-NPs was quantified through flow cytometry in J774A.1 cell line, and a 23.90 fold rise in uptake was observed. Fluorescent microscopy also confirmed the time dependent rise in uptake. In-vivo multiple dose toxicity study demonstrated no toxicity upto 5 mg/kg dose of AmB. Plasma kinetics and tissue distribution studies established significantly higher concentration of AmB in group treated with CaP-AmB-NPs in liver and spleen as compared to CAmB, LAmB and AmB suspension group. In-vivo animal experimental results revealed that the CaP-AmB-NPs showed higher splenic parasite inhibition compared to CAmB and LAmB in leishmania parasite infected hamsters. Conclusions: The investigated CaP-AmB-NPs are effective in provoking macrophage mediated uptake and collectively features lower toxicity and offers a suitable replacement for available AmB-formulations for the obliteration of intra-macrophage VL parasite

Enhanced oral bioavailability of levormeloxifene and raloxifene by nanoemulsion: simultaneous bioanalysis using liquid chromatography-tandem mass spectrometry

Aim & objective: Levormeloxifene (L-ORM) and raloxifene (RAL) are selective estrogen receptor modulators used in the treatment of postmenopausal osteoporosis and breast cancer. Here, we developed and validated a liquid chromatography-tandem mass spectrometry (LC–MS/MS) method for the simultaneous estimation of both drugs. Materials & methods: A quality-by-design (QbD) approach was used for the optimization of the nanoemulsion, and US FDA guidelines were followed for method validation. Results: Multiple reaction monitoring transitions were used for L-ORM (459.05→98.50), RAL (475.00→112.02) and internal standard (180.10→110.2). Analytes were resolved in a C18 column with 80:20 v/v% acetonitrile (ACN), 0.1% formic acid in triple-distilled water as a mobile phase. The developed method was linear over a concentration range of 1–600 ng/ml. Pharmacokinetic results of free L-ORM–RAL and the L-ORM–RAL nanoemulsion showed Cmax of free L-ORM – 70.65 } 16.64, free RAL 13.53 } 2.72, LORM nanoemulsion 65.07 } 14.0 and RAL-nanoemulsion 59.27 } 17.44 ng/ml. Conclusion: Future findings will contribute to the treatment of postmenopausal osteoporosis and breast cancer using L-ORM and RAL.</p