Co-Delivery of siRNA and Docetaxel to Cancer Cells by NLC for Therapy

The present study aims to develop a delivery system that can carry small interference RNA (siRNA) with small-molecule chemotherapeutic drugs, which can be used in cancer treatment. The drug delivery system combines the advantages of a therapeutic agent with two different mechanisms to ensure that it is used efficiently for cancer therapy. In this study, a nanostructured lipid carrier system was prepared, Docetaxel was loaded to these systems, and the Eph siRNA was adsorbed to the outer surface. In addition, DOTAP was added to the lipophilic phase to load a positive charge on the lipidic structure for interaction with the cells. Moreover, characterization, cytotoxicity, and transfection procedures were performed on the whole system. This candidate system was also compared to Taxotere, which is the first approved Docetaxel-containing drug on the market. Given the results, it was determined that the particle size of NLC-DTX was 165.3 ± 3.5 nm, the ζ potential value was 38.2 ± 1.7 mV, and the PDI was 0.187 ± 0.024. Entrapment efficacy of nanoparticles was found to be 92.89 ± 0.21%. It was determined that the lipidic system prepared in vitro release analyses were able to provide sustained release and exhibit cytotoxicity, even at doses lower than the dose used for Taxotere. The formulations prepared had a higher level of effect on cells when compared with pure DTX and Taxotere, but they also exhibited time-dependent cytotoxicity. It was also observed that the use of Eph siRNA together with the chemotherapeutic agent via formulation also contributed to this cell death. The results of the present study indicate that there is a promising carrier system in order to deliver hydrophilic nucleic acids, such as siRNA, together with lipophilic drugs in cancer treatment.

Nanostructured Lipid Carrier Co-Loaded with Docetaxel and Magnetic Nanoparticles: Physicochemical Characterization and In Vitro Evaluation

Lung cancer is currently the most prevalent cause of cancer mortality due to late diagnosis and lack of curative therapies. Docetaxel (Dtx) is clinically proven as effective, but poor aqueous solubility and non-selective cytotoxicity limit its therapeutic efficacy. In this work, a nanostructured lipid carrier (NLC) loaded with iron oxide nanoparticles (IONP) and Dtx (Dtx-MNLC) was developed as a potential theranostic agent for lung cancer treatment. The amount of IONP and Dtx loaded into the Dtx-MNLC was quantified using Inductively Coupled Plasma Optical Emission Spectroscopy and high-performance liquid chromatography. Dtx-MNLC was then subjected to an assessment of physicochemical characteristics, in vitro drug release, and cytotoxicity. Dtx loading percentage was determined at 3.98% w/w, and 0.36 mg/mL IONP was loaded into the Dtx-MNLC. The formulation showed a biphasic drug release in a simulated cancer cell microenvironment, where 40% of Dtx was released for the first 6 h, and 80% cumulative release was achieved after 48 h. Dtx-MNLC exhibited higher cytotoxicity to A549 cells than MRC5 in a dose-dependent manner. Furthermore, the toxicity of Dtx-MNLC to MRC5 was lower than the commercial formulation. In conclusion, Dtx-MNLC shows the efficacy to inhibit lung cancer cell growth, yet it reduced toxicity on healthy lung cells and is potentially capable as a theranostic agent for lung cancer treatment.

Engineered Nano-carrier Systems for the oral targeted delivery of Follicle Stimulating Hormone: Development, characterization, and, assessment of in vitro and in vivo performance and targetability

Follicle stimulating hormone (FSH) is widely used for the treatment of female infertility, where the level of FSH is suboptimal due to which arrest in follicular development and anovulation takes place. Currently, only parenteral formulations are available for FSH in the market. Due to the drawbacks of parenteral administration and the high market shares of FSH, there is a need for easily accessible oral formulation. Therefore, enteric coated capsules filled with FSH loaded nanostructured lipid carriers (NLCs) or liposomes were prepared. Preliminary studies such as circular dichroism, SDS-PAGE, FTIR and ELISA were conducted to analyze FSH. Prepared formulations were optimized with respect to the size, polydispersity index, zeta potential, and entrapment efficiency using the design of experiments. Optimized formulations were subjected to particle counts and distribution analysis, TEM analysis, in vitro drug release, dissolution of enteric coated capsules, cell line studies, everted sac rat's intestinal uptake study, pharmacokinetics, pharmacodynamics, and stability studies. In the case of liposomes, RGD conjugation was done by carbodiimide chemistry and conjugation was confirmed by FTIR, ¹HNMR and Raman spectroscopy. The prepared formulations were discrete and spherical. The release of FSH from enteric coated capsules was slow and sustained. The increased permeability of nano-formulations was observed in Caco-2 monoculture as well as in Caco-2 and Raji-B co-culture models. NLCs and liposomes showed an improvement in oral bioavailability and efficacy of FSH in rats. This may be due to mainly chylomicron-assisted lymphatic uptake of NLCs; whereas, in the case of liposomes, RGD-based targeting of β1 integrins of M cells on Peyer's patches may be the main reason for the better effect by FSH. FSH was found to be stable chemically and conformationally. Overall, the study reveals the successful development and evaluation of FSH loaded NLCs and liposomes.

Surface-modified nanoparticles of docetaxel for chemotherapy of lung cancer: An intravenous to oral switch

Despite being potent, the marketed formulations of Docetaxel (DX) are associated with numerous side effects and are meant for intravenous administration. Advanced pharmaceutical nanotechnology has a significant potential to facilitate the 'intravenous (i.v) to oral switch'. The present research work deals with the development of an orally administrable, folate-receptor-targeted Nanostructured lipid carriers (NLCs) of DX (FA-DX-NLCs) for facilitating oral chemotherapy of lung cancer while overcoming the bioavailability and toxicity issues. The nanoformulation prepared to employ high-pressure homogenization and lyophilization, was evaluated and statistically analyzed for various in-vitro and in-vivo formulation characteristics. The lyophilized nanoparticles were observed to be spherical with a particle size of 183.4 ± 2.13 (D90), Pdi of 0.358 ± 0.03, % EE of 82.41 ± 2.44, % DL of 4.41 ± 0.54 and a zeta potential of -3.3 ± 0.7 mv. The increased oral in-vivo bioavailability of DX was evident from the plasma-concentration area under the time curve (AUC_0-t), which was ∼ 27-fold greater for FA-DX-NLCs as compared to DX suspension. The orally administered FA-DX-NLCs exhibited excellent antitumor efficacy in a pre-clinical model of lung carcinoma. Tumor staging, histopathology, and immunostaining of the tumors suggested greater anti-proliferative, apoptotic, anti-metastatic, and anti-angiogenic potential as compared to DX-suspension. The pre-clinical toxicity studies affirmed the excellent safety and bio-compatibility of FA-DX-NLCs. The research work presents immense translational potential for switching the DX-based chemotherapy for lung cancer from 'hospital to home.'

Design and Evaluation of Two-Step Biorelevant Dissolution Methods for Docetaxel Oral Formulations

Dissolution is a pivotal tool for oral formulations. Dissolution could be used to either reduce the risk of product failure through quality control or predict and understand in vivo performance of drug formulations. The latter is always challenging because multiple factors such as selection of media, gastrointestinal components, physiological factors, consideration of fasted and fed state are involved. Previously published dissolution methods such as one-step dissolution in individual simulated gastric fluid, simulated intestinal fluid, or phosphate buffer saline did not signify the realistic gastrointestinal transit effect. Docetaxel (DTX), a poorly water-soluble drug, is commercially available only as injectable dosage forms, and thus many publications studied the development of oral DTX formulations. In our previous report, we developed oral lipid-based DTX granules that showed higher oral absorption in rats compared to DTX powder. However, one-step dissolution in simulated gastric fluid showed no difference between DTX granules and DTX powder. Therefore, the present study aimed to develop new two-step biorelevant dissolution methods for DTX oral formulations. In the study, new two-step biorelevant dissolution methods in fasted or fed states with pancreatin were developed and compared with other previously reported dissolution methods. The new two-step biorelevant dissolution methods successfully discriminated the difference of dissolution between DTX granules and DTX powder, which reflected the in vivo difference of absorption of these two formulations. Moreover, food effects were confirmed for DTX. The new dissolution methods have the potential to be used to predict and understand in vivo performance of oral solid dosage forms.

Interaction of Docetaxel with Phosphatidylcholine Membranes: A Combined Experimental and Computational Study

The antineoplastic drug Docetaxel is a second generation taxane which is used against a great variety of cancers. The drug is highly lipophilic and produces a great array of severe toxic effects that limit its therapeutic effectiveness. The study of the interaction between Docetaxel and membranes is very scarce, however, it is required in order to get clues in relation with its function, mechanism of toxicity and possibilities of new formulations. Using phosphatidylcholine biomimetic membranes, we examine the interaction of Docetaxel with the phospholipid bilayer combining an experimental study, employing a series of biophysical techniques like Differential Scanning Calorimetry, X-Ray Diffraction and Infrared Spectroscopy, and a Molecular Dynamics simulation. Our experimental results indicated that Docetaxel incorporated into DPPC bilayer perturbing the gel to liquid crystalline phase transition and giving rise to immiscibility when the amount of the drug is increased. The drug promotes the gel ripple phase, increasing the bilayer thickness in the fluid phase, and is also able to alter the hydrogen-bonding interactions in the interfacial region of the bilayer producing a dehydration effect. The results from computational simulation agree with the experimental ones and located the Docetaxel molecule forming small clusters in the region of the carbon 8 of the acyl chain palisade overlapping with the carbonyl region of the phospholipid. Our results support the idea that the anticancer drug is embedded into the phospholipid bilayer to a limited amount and produces structural perturbations which might affect the function of the membrane.

Drug delivery to the intestinal lymph by oral formulations

Oral drug delivery systems (DDS) targeting lymphocytes in intestinal lymphatic vessels, ducts, and nodes are useful for treating diverse diseases. The intestinal lymph harbors numerous lymphocyte subsets, and DDS containing lipids such as triglycerides and fatty acids can deliver drugs to the lymph through the chylomicron pathway. DDS are efficient, thus allowing the administration of reduced drug doses, which mitigate systemic adverse effects. Here we review orally administered lipid formulations comprising oil solutions, suspensions, micro/nanoemulsions, self-micro/nano emulsifying DDS, liposomes, micelles, solid lipid nanoparticles, and nanostructured lipid carriers for targeting drugs to the lymph. We first describe the structures of lymphatic vessels and lymph nodes and the oral absorption of lipids and drugs into the intestinal lymph. We next summarize the effects of the properties and amounts of lipids and drugs delivered into the lymph and lymphocytes, as well as their effects on drug delivery ratios of lymph to blood. Finally, we describe lymphatic DDS containing saquinavir, tacrolimus, and methotrexate, and their potency that reduce drug concentrations in blood, which are associated with systemic adverse effects.

Dual loaded nanostructured lipid carrier of nano-selenium and Etravirine as a potential anti-HIV therapy

There is a dire need for dual-long-acting therapy that could simultaneously target different stages of the HIV life cycle and providing a dual-prolonged strategy for improved anti-HIV therapy while reducing oxidative stress associated with the prolonged treatment. Thus, in the present work, nanostructured lipid carriers of Etravirine were developed and modified with nano-selenium. The dual-loaded nanocarrier system was fabricated using the double emulsion solvent evaporation method, further screened and optimized using the design of experiments methodology. The spherical core-shell type of a system was confirmed with an electron microscope and small-angle neutron scattering, while XPS confirmed the presence of selenium at the core-shell of the nanocarrier. In vitro assessment against HIV1 (R5 and X4 strains) infected TZM-bl cells exhibited higher efficacy for the dual-loaded nanocarrier system than the plain drug, which could be attributed to the synergistic effect of the nano-selenium. Confocal microscopy and flow cytometry results exhibited enhanced uptake in TZM-bl cells compared to plain drug. A significant increase of GSH, SOD, CAT was observed in animals administered with the dual-loaded nanocarrier system containing nano-selenium, suggesting the protective potential of the lipidic nanoparticle containing the nano-selenium. Improvement in the in vivo pharmacokinetic parameters was also observed, along with a higher accumulation of the dual-loaded nanocarrier in remote HIV reservoir organs like the brain, ovary, and lymph node. The results suggest the potential of a dual-loaded formulation for synergistically targeting the HIV1 infection while simultaneously improving the intracellular anti-oxidant balance for improving a prolonged anti-HIV therapy.

An update on oral drug delivery via intestinal lymphatic transport

Orally administered drug entities have to survive the harsh gastrointestinal environment, penetrate the enteric epithelia and circumvent hepatic metabolism before reaching the systemic circulation. Whereas the gastrointestinal stability can be well maintained by taking proper measures, hepatic metabolism presents as a formidable barrier to drugs suffering from first-pass metabolism. The pharmaceutical academia and industries are seeking alternative pathways for drug transport to circumvent problems associated with the portal pathway. Intestinal lymphatic transport is emerging as a promising pathway to this end. In this review, we intend to provide an updated overview on the rationale, strategies, factors and applications involved in intestinal lymphatic transport. There are mainly two pathways for peroral lymphatic transport-the chylomicron and the microfold cell pathways. The underlying mechanisms are being unraveled gradually and nowadays witness increasing research input and applications.

Quality by design (QbD)-based fabrication of atazanavir-loaded nanostructured lipid carriers for lymph targeting: bioavailability enhancement using chylomicron flow block model and toxicity studies

Atazanavir (ATV) is widely used as anti-HIV agent having poor aqueous solubility needs to modulate novel drug delivery system to enhance therapeutic efficiency and safety. The main objective of the present work was to fabricate ATV-loaded nanostructured lipid carriers (NLCs) employing quality by design (QbD) approach to address the challenges of bioavailability and their safety after oral administration. Herein, the main objective was to identify the influencing variables for the production of quality products. Considering this objective, quality target product profile (QTPP) was assigned and a systematic risk assessment study was performed to identify the critical material attributes (CMAs) and critical process parameter (CPP) having an influence on critical quality attributes (CQAs). Lipid concentrations, surfactant concentrations, and pressure of high-pressure homogenizer were identified as CMAs and CPP. ATV-NLCs were prepared by emulsification-high pressure homogenization method and further lyophilized to obtain solid-state NLCs. The effect of formulation variables (CMAs and CPP) on responses like particle size (Y₁), polydispersity index (Y₂), and zeta potential (Y₃) was observed by central composite rotatable design (CCRD). The data were statistically evaluated by ANOVA for confirmation of a significant level (p < 0.05). The optimal conditions of NLCs were obtained by generating design space and desirability value. The lyophilized ATV-NLCs were characterized by DSC, powder X-ray diffraction, and FT-IR analysis. The morphology of NLCs was revealed by TEM and FESEM. In vitro study suggested a sustained release pattern of drug (92.37 ± 1.03%) with a mechanism of Korsmeyer-Peppas model (r² = 0.925, and n = 0.63). In vivo evaluation in Wistar rats showed significantly higher (p < 0.001) plasma drug concentration of ATV-NLCs as compared to ATV-suspension using chylomicron flow block model. The relative bioavailability of ATV-NLCs was obtained to be 2.54 folds. Thus, a safe and promising drug targeting system was successfully developed to improve bioavailability and avoiding first-pass effect ensures to circumvent the acute-toxicity of liver.

Enhanced solubility and biopharmaceutical performance of atorvastatin and metformin via electrospun polyvinylpyrrolidone-hyaluronic acid composite nanoparticles

The study was aimed to improve the aqueous solubility of atorvastatin (AT) and ameliorate permeability of metformin (MT) in a combination formulation, improving their oral bioavailability. Several AT-MT loaded polyvinylpyrrolidone (PVP) and hyaluronic acid (HA) based nanoparticles were prepared through electrospraying method (ES-NPs), and tested for physicochemical, in vitro, and in vivo parameters. Among the trialed formulations, a sample consisting of AT, MT, PVP, and HA at the weight ratio of 1/6.25/3.75/15 furnished the most satisfying solubility and release rate results. It enhanced approximately 10.3-fold and 3.6-fold solubility of AT as compared with AT powder and marketed product (Lipilow) in phosphate buffer pH = 6.8, respectively. Whereas, permeation of MT was 1.60-fold and 1.47-fold improved as compared with MT powder and marketed product (Glucophage), respectively. As compared with Lipilow, AUC _(0-∞) and C_max of AT with ES-NPs in rats were improved to 3.6-fold and 3.2-fold, respectively. Similarly, as compared with Glucophage, AUC _(0-∞) and C_max of MT were improved to 2.3-fold and 1.8-fold, respectively. Thus, ES-NPs significantly enhanced the solubility of AT (a BCS class II drug) and permeability of MT (a BCS class III drug) and might be a promising drug delivery system for co-delivery of these drugs.

Enhanced oral bioavailability of nintedanib esylate with nanostructured lipid carriers by lymphatic targeting: In vitro, cell line and in vivo evaluation

The present research work was aimed to explore the ability of nanostructured lipid carriers (NLCs) to improve oral bioavailability of Nintedanib esylate (NE) via lymphatic uptake. The NE loaded NLCs (NE-NLCs) were fabricated using high speed homogenization followed by probe sonication method and physiochemically characterized. The NE-NLCs had particle size of 125.7 ± 5.5 nm, entrapment efficiency of 88.5 ± 2.5% and zeta potential of -17.3 ± 3.5 mV. DSC and XRD studies indicated that NE was converted to amorphous form. TEM images showed uniformly distributed spherical shaped particles. In vitro release study of NE-NLCs showed drug release of 6.87 ± 2.72% in pH 1.2 and 92.72 ± 3.40% in phosphate buffer pH 6.8 and obeyed higuchi model. Lipolysis study showed higher amount of drug in aqueous layer in NE-NLCs compared to NE-suspension. Tissue distribution study showed deeper penetration of FITC loaded NLCs compared to FITC solution. The cellular uptake across Caco-2 cells exhibited more uptake of FITC loaded NLCs. Cytotoxicity study using A549 cell line revealed higher potential of NE-NLCs in inhibiting tumor cell growth in comparison to that of suspension. The oral bioavailability of NE was ameliorated over 26.31 folds after inclusion into NLCs in contrast to NE-suspension. Intestinal lymphatic uptake of NE-NLCs in cycloheximide treated mice was lower as compared to control without cycloheximide treatment. Thus, the developed NE-NLCs can be an encouraging delivery strategy for increasing oral bioavailability of NE via lymphatic uptake.

Development, in vitro and in vivo evaluation of miltefosine loaded nanostructured lipid carriers for the treatment of Cutaneous Leishmaniasis

The purpose of this study was to enhance the anti-leishmanial efficacy of miltefosine (MTF) and reduce its toxic effects by loading it into nanostructured lipid carriers (NLCs). Micro-emulsion technique was used to prepare MTF-loaded NLCs. The optimized NLCs were characterized in terms of various physicochemical parameters including particle size, poly dispersity index (PDI), zeta potential, transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) technique. In vitro and in vivo assays were performed to evaluate the potential of NLCs as an effective nanocarrier system for oral delivery of MTF in Cutaneous Leishmaniasis. The optimized MTF-loaded NLCs exhibited mean particle size of 160.8 ± 5.3 nm with narrow PDI and high incorporation efficiency (IE%) of 96.17 ± 1.3%. MTF-loaded NLCs demonstrated slow release of the incorporated drug as compared to the drug solution. The optimized formulation showed significant decrease in hemolytic potential, 2.5~folds increase in anti-leishmanial efficacy and 6~fold decrease in macrophage cytotoxicity as compared to MTF solution, in vitro. Macrophage uptake study confirmed passive targeting ability of MTF-loaded NLCs. In-vivo analysis demonstrated enhanced anti-leishmanial effect of the MTF-loaded NLCs and better pharmacokinetic profiles with no gastrointestinal (GI) toxicity. NLCs are potential nanocarriers for the oral delivery of MTF with enhanced anti-leishmanial activity, better safety profile and reduced hemolytic potential.

Advanced delivery strategies facilitating oral absorption of heparins

Heparins show great anticoagulant effect with few side effects, and are administered by subcutaneous or intravenous route in clinics. To improve patient compliance, oral administration is an alternative route. Nonetheless, oral administration of heparins still faces enormous challenges due to the multiple obstacles. This review briefly analyzes a series of barriers ranging from poorly physicochemical properties of heparins, to harsh biological barriers including gastrointestinal degradation and pre-systemic metabolism. Moreover, several approaches have been developed to overcome these obstacles, such as improving stability of heparins in the gastrointestinal tract, enhancing the intestinal epithelia permeability and facilitating lymphatic delivery of heparins. Overall, this review aims to provide insights concerning advanced delivery strategies facilitating oral absorption of heparins.

Lymphatic Transport of Drugs after Intestinal Absorption: Impact of Drug Formulation and Physicochemical Properties

PURPOSE

To provide a comprehensive and up-to-date overview focusing on the extent of lymphatic transport of drugs following intestinal absorption and to summarize available data on the impact of molecular weight, lipophilicity, formulation and prandial state.

METHODS

Literature was searched for in vivo studies quantifying extent of lymphatic transport of drugs after enteral dosing. Pharmacokinetic data were extracted and summarized. Influence of molecular weight, log P, formulation and prandial state was analyzed using relative bioavailability via lymph (F_RL) as the parameter for comparison. The methods and animal models used in the studies were also summarized.

RESULTS

Pharmacokinetic data on lymphatic transport were available for 103 drugs. Significantly higher F_RL [median (IQR)] was observed in advanced lipid based formulations [54.4% (52.0)] and oil solutions [38.9% (60.8)] compared to simple formulations [2.0% (27.1)], p < 0.0001 and p = 0.004, respectively. Advanced lipid based formulations also provided substantial F_RL in drugs with log P < 5, which was not observed in simple formulations and oil solutions. No relation was found between F_RL and molecular weight. There were 10 distinct methods used for in vivo testing of lymphatic transport after intestinal absorption so far.

CONCLUSION

Advanced lipid based formulations provide superior ability to increase lymphatic absorption in drugs of various molecular weights and in drugs with moderate to low lipophilicity.

Excipient selection and aerodynamic characterization of nebulized lipid-based nanoemulsion loaded with docetaxel for lung cancer treatment

Docetaxel has demonstrated extraordinary anticancer effects on lung cancer. However, lack of optimal bioavailability due to poor solubility and high toxicity at its therapeutic dose has hampered the clinical use of this anticancer drug. Development of nanoemulsion formulation along with biocompatible excipients aimed for pulmonary delivery is a potential strategy to deliver this poorly aqueous soluble drug with improved bioavailability and biocompatibility. In this work, screening and selection of pharmaceutically acceptable excipients at their minimal optimal concentration have been conducted. The selected nanoemulsion formulations were prepared using high-energy emulsification technique and subjected to physicochemical and aerodynamic characterizations. The formulated nanoemulsion had mean particle size and ζ-potential in the range of 90 to 110 nm and - 30 to - 40 mV respectively, indicating high colloidal stability. The pH, osmolality, and viscosity of the systems met the ideal requirement for pulmonary application. The DNE4 formulation exhibited slow drug release and excellent stability even under the influence of extreme environmental conditions. This was further confirmed by transmission electron microscopy as uniform spherical droplets in nanometer range were observed after storage at 45 ± 1 °C for 3 months indicating high thermal stability. The nebulized DNE4 exhibited desirable aerosolization properties for pulmonary delivery application and found to be more selective on human lung carcinoma cell (A549) than normal cell (MRC-5). Hence, these characteristics make the formulation a great candidate for the potential use as a carrier system for docetaxel in targeting lung cancer via pulmonary delivery.

Fabrication, optimization, and in vitro evaluation of docetaxel-loaded nanostructured lipid carriers for improved anticancer activity

Lung cancer is the leading cause of cancer-related deaths in both men and women worldwide. It is the leading cancer killer in both men and women in every Ethnic Group. A major problem associated with chemotherapies against their lung cancer is the lack of selective toxicity, which results in a narrow therapeutic index thereby compromising clinical prognosis. To circumvent these challenges, the present investigation sought to develop a docetaxel-loaded nanostructured lipid carrier system (DTX-NLCS) for the treatment of lung cancer. A 3-factor/3-level Box-Behnken Design was applied to systematically optimize the DTX-NLCS parameters. The amount of drug, emulsifier concentration, and homogenization speed was selected as independent variables, while the particle size and % entrapment efficiency (%EE) were selected as dependent variables. The optimized batch parameters were 29.81 mg drug, 19.97% w/w emulsifier, and 13 200 (rpm) speed of homogenization with a mean particle size of 154.1 ± 3.13 nm and a mean %EE of 86.12 ± 3.48%. The in vitro lipolysis experiments revealed that the optimized DTX-NLCs were stabilized by 10% w/w PEG 4000 mono-stearate and exhibited an anti-lipolytic effect. Furthermore, the in vitro gastrointestinal stability studies (at pH-1.2, pH-4.5, pH-6.8, and pH-7.4) revealed that the optimized developed system could withstand various GI tract media. The in vitro dissolution studies depicted a pH-independent controlled-release consistent with the Weibull model. In vitro cytotoxicity studies using NCI-H460 cell lines further revealed that there was a reduction in IC₅₀ values in the DTX-NLCS treated cells as compared to those treated with the pure drug, indicating an improved efficiency for the developed system.

Silymarin and silymarin nanoparticles guard against chronic unpredictable mild stress induced depressive-like behavior in mice: involvement of neurogenesis and NLRP3 inflammasome

BACKGROUND

The neuropathology of depression is quite complex. Thus, treatment failures are frequent with current antidepressants, raising the need for more effective ones.

AIMS

This study aimed to investigate the influence of silymarin on depressive-like behavior induced by chronic unpredictable mild stress (CUMS) and explore the underlying mechanisms.

METHODS

Silymarin was formulated as nanostructured lipid carriers (a lipid-based type of nanoparticle with the advantages of physical stability, good release profile, and targeted delivery). Mice were subjected to CUMS paradigm during 14 days. During this period, mice received silymarin (200 mg/kg, p.o.) per se or in its nanoparticle form or fluoxetine (10 mg/kg, p.o.). On the 15th day behavioral and biochemical parameters were analyzed.

RESULTS

Oral administration of silymarin (200 mg/kg), particularly in its nanoparticulate form, exerted an antidepressant-like effect, comparable with fluoxetine in mice, as demonstrated in the behavioral despair tests. Silymarin also reversed prefrontal cortical and hippocampal CUMS-induced oxidative stress and neuroinflammation. Furthermore, silymarin augmented neurotransmitter levels, enhanced neurogenesis and inhibited nod-like receptor protein 3 inflammasome activation. Silymarin nanoparticles were superior to silymarin in certain parameters probably due to significantly higher brain silybinin (the major active component of silymarin) concentration by 12.46 fold in the group administered silymarin nanoparticles compared with the mice which were administered silymarin per se.

CONCLUSIONS

The antidepressant-like effect of silymarin can be attributed to its antioxidant and anti-inflammatory effects as well as increased neurogenesis in the prefrontal cortex and hippocampus, which delineates silymarin, especially in nanoparticle form, as a promising strategy for treatment of depression.

Asenapine maleate-loaded nanostructured lipid carriers: optimization and in vitro, ex vivo and in vivo evaluations

AIM

To prepare nanostructured lipid carriers (NLCs) loaded with asenapine maleate (ASPM) to increase its oral bioavailability by intestinal lymphatic uptake.

MATERIALS & METHODS

ASPM-NLCs were prepared by ultrasound dispersion technique, by adopting Design of Experiment approach, and characterized.

RESULTS

The optimized formulation exhibited good physicochemical parameters. Differential scanning calorimetry and x-ray diffraction studies indicated the amorphized nature of ASPM in lipid matrix. In vitro drug release study indicated the sustained release of drug from NLCs. ASPM-NLCs showed greater permeability across Caco2 cells and everted rat ileum. ASPM-NLCs showed greater cellular uptake, superior preclinical oral bioavailability and higher efficacy in reducing the L-DOPA-carbidopa-induced locomotor count compared with plain drug.

CONCLUSION

ASPM-NLCs were successfully developed that showed enhanced performance both in vitro and in vivo.

Potential of Lipid Nanoparticles (SLNs and NLCs) in Enhancing Oral Bioavailability of Drugs with Poor Intestinal Permeability

Lipid-based drug delivery systems has become a popular choice for oral delivery of lipophilic drugs with dissolution rate limited oral absorption. Lipids are known to enhance oral bioavailability of poorly water-soluble drugs in multiple ways like facilitating dissolution as micellar solution, enhancing the lymphatic uptake and acting as inhibitors of efflux transporters. Lipid nanoparticles are matrix type lipid-based carrier systems which can effectively encapsulate both lipophilic and hydrophilic drugs. Lipid nanoparticles namely solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) are versatile drug delivery system and can be used for multiple routes of delivery like parenteral, topical, ocular, transdermal, and oral. Lipid nanoparticles are particularly attractive vehicles for peroral delivery of drugs with oral bioavailability problems as they are composed of lipid excipients which are cheap, easily available, and non-toxic; manufacturing technique is simple and readily scalable for large-scale production; the formulations provide controlled release of active components and have no stability issue. A large number of drugs have been incorporated into lipid nanoparticles with the objective of overcoming their poor oral bioavailability. This review tries to assess the potential of lipid nanoparticles for enhancing the oral bioavailability of drugs with permeability limited oral absorption such as drugs belonging to class IV of Biopharmaceutic Classification System (BCS) and protein and peptide drugs and also discusses the mechanism behind the bioavailability enhancement and safety issues related to such delivery systems.

Nanocolloidal lipidic carriers of olmesartan medoxomil surface-tailored with Concavalin-A for lectin receptor targeting

Aim: The present work involves the development of Concavalin A-conjugated nanostructured lipidic carriers (NLCs) of olmesartan medoxomil for lectin receptor targeting. Materials & methods: Excipient selection was performed by drug solubility in solid and liquid lipids. Factor screening was carried out by evaluating the impact of formulation and process variables on the critical quality attributes. Surface modification of NLCs was carried out using Concavalin A and extensively characterized. Results & conclusion: NLCs exhibited the particle size of 273.6 nm, ζ-potential of -30.2 nm, encapsulation efficiency of 73.3% and sustained drug release profile. Nearly 4.2-fold improvement in cell uptake, four- to eightfold increase in Cmax and AUC, and 37% reduction in blood pressure was observed from NLCs over the pure drug.

Cell penetrating peptides functionalized gambogic acid-nanostructured lipid carrier for cancer treatment

Tumor-targeted delivery is considered a crucial component of current anticancer drug development and is the best approach to increase the efficacy and reduce the toxicity. Nanomedicine, particularly ligand-based nanoparticles have shown a great potential for active targeting of tumor. Cell penetrating peptide is one of the promising ligands in a targeted cancer therapy. In this study, the gambogic acid-loaded nanostructured lipid carrier (GA-NLC) was modified with two kinds of cell penetrating peptides (cRGD and RGERPPR). The GA-NLC was prepared by emulsification and solvent evaporation method and coupled with cRGD, RGERPPR, and combination cRGD and RGERPPR to form GA-NLC-cRGD, GA-NLC-RGE, and GA-NLC-cRGD/RGE, respectively. The formulations were characterized by their particle size and morphology, zeta potential, encapsulation efficiency, and differential scanning calorimetry. In vitro cytotoxicity and cellular uptake study of the formulations were performed against breast cancer cell (MDA-MB-231). Furthermore, in vivo biodistribution and antitumor activity of the formulations were determined by in vivo imaging and in tumor-bearing nude mice, respectively. The result of in vitro cytotoxicity study showed that GA-NLC-RGE exhibited a significantly higher cytotoxicity on MDA-MB-231 as compared with GA-NLC and GA-Sol. Similarly, RGE-Cou-6-NLC showed remarkably higher uptake by the cells than other NLCs over the incubation period. The in vivo imaging study has demonstrated that among the formulations, the RGE-decorated DiR-NLC were more accumulated in the tumor site. The in vivo antitumor activity revealed that RGE-GA-NLC inhibits the tumor growth more efficiently than other formulations. In conclusion, RGERPPR has a potential as an effective carrier in targeting drug delivery of anticancer agents.

VE-Albumin Core-Shell Nanoparticles for Paclitaxel Delivery to Treat MDR Breast Cancer

Multi-drug resistance (MDR) presents a serious problem in cancer chemotherapy. In this study, Vitamin E (VE)-Albumin core-shell nanoparticles were developed for paclitaxel (PTX) delivery to improve the chemotherapy efficacy in an MDR breast cancer model. The PTX-loaded VE-Albumin core-shell nanoparticles (PTX-VE NPs) had small particle sizes (about 100 nm), high drug entrapment efficiency (95.7%) and loading capacity (12.5%), and showed sustained release profiles, in vitro. Docking studies indicated that the hydrophobic interaction and hydrogen bonds play a significant role in the formation of the PTX-VE NPs. The results of confocal laser scanning microscopy analysis demonstrated that the cell uptake of PTX was significantly increased by the PTX-VE NPs, compared with the NPs without VE (PTX NPs). The PTX-VE NPs also exhibited stronger cytotoxicity, compared with PTX NPs with an increased accumulation of PTX in the MCF-7/ADR cells. Importantly, the PTX-VE NPs showed a higher anti-cancer efficacy in MCF-7/ADR tumor xenograft model than the PTX NPs and the PTX solutions. Overall, the VE-Albumin core-shell nanoparticles could be a promising nanocarrier for PTX delivery to improve the chemotherapeutic efficacy of MDR cancer.

QbD-driven development and evaluation of nanostructured lipid carriers (NLCs) of Olmesartan medoxomil employing multivariate statistical techniques

PURPOSE

This research work entails quality by design (QbD)-based systematic development of nanostructured lipid carriers (NLCs) of Olmesartan medoxomil (OLM) with improved biopharmaceutical attributes.

METHODS

Quality target product profile (QTPP) was defined and critical quality attributes (CQAs) were earmarked. Solubility of drug was performed in various lipids for screening of them. NLCs were prepared by hot-microemulsion method using solid lipids, liquid lipids and surfactants with maximal solubility. Failure mode and effect analysis (FMEA) was carried out for identifying high risk formulation and process parameters. Further, principal component analysis (PCA) was applied on high risk parameters for evaluating the effect of type and concentration of lipids and surfactants on CQAs. Further, systematic optimization of critical material attributes (CMAs) was carried out using face centered cubic design and optimized formulation was identified in the design space.

RESULTS

FMEA and PCA suggested suitability of stearic acid, oleic acid and Tween 80 as the CMAs for NLCs. Response surface optimization helped in identifying the optimized NLC formulation with particle size ∼250 nm, zeta potential <25 mV, entrapment efficiency >75%, in vitro drug release >80% within 6 h. Release kinetic modeling indicated drug release through Fickian-diffusion mechanism.

CONCLUSIONS

Overall, these studies indicated successful development of NLCs using multivariate statistical approaches for improved product and process understanding.

Polyester-Solid Lipid Mixed Nanoparticles with Improved Stability in Gastro-Intestinal Tract Facilitated Oral Delivery of Larotaxel

The objective of this study was to investigate the role of core stability of nanoparticles on their performances in oral drug delivery. Solid lipids (Geleol Mono and Diglycerides Nf) were incorporated into nanoparticles composed of mPEG-b-PCL by the dialysis method. The prepared solid lipid loaded nanoparticles were found to be spherical nanoparticles with a core state and size distribution dependent on the amount of solid lipid incorporated. The critical aggregation concentrations of lipid-loaded nanoparticles were determined using pyrene fluorescence. Then, the stability of block copolymer in nanoparticles with different solid lipid contents was studied in simulated gastric fluid and simulated intestinal fluid. Solid lipids were found to stabilize nanoparticle cores by improving not only the thermodynamic stability (lowered CAC) of the nanoparticle but also the chemical stability of the block copolymer in the gastrointestinal environment. The stability of the loaded drug (larotaxel, LTX) in nanoparticles with different solid lipid contents was challenged by intestinal homogenate and rat liver microsome, and solid lipid loaded nanoparticles showed superior drug-protecting capability. Solid lipid incorporation exhibited limited influence on the cytotoxicity and cellular uptake but improved the transcytosis of nanoparticles in Caco-2 monolayers. The results of pharmacokinetic study indicated that core stabilization was helpful in promoting oral larotaxel absorption as the absolute bioavailability of LTX delivered by solid lipid loaded nanoparticles was found to be 13.17%, compared with that by the lipid-free nanoparticles (6.264%) and LTX solution (2.435%). Additionally, the results of biodistribution study indicated relatively higher particle integrity of solid lipid loaded nanoparticles, shown by slower liver and spleen accumulation rate, compared with its lipid-free counterpart. Overall, incorporation of solid lipids made the nanoparticles more suitable for oral drug delivery.

Sustained release docetaxel-incorporated lipid nanoparticles with improved pharmacokinetics for oral and parenteral administration

The aim of this study was to develop docetaxel-incorporated lipid nanoparticles (DTX-NPs) to improve the pharmacokinetic behaviour of docetaxel (DTX) after oral and parenteral administration via sustained release. DTX-NPs were prepared by nanotemplate engineering technique with palmityl alcohol as a solid lipid and Tween-40/Span-40/Myrj S40 as a surfactants mixture. Spherical DTX-NPs below 100 nm were successfully prepared with a narrow particle size distribution, 96% of incorporation efficiency and 686 times increase in DTX solubility. DTX-NPs showed a sustained release over 24 h in phosphate-buffered saline and simulated gastric and intestinal fluids, while DTX-micelles released DTX completely within 12 h. The half-maximal inhibitory concentration (IC₅₀) of DTX-NPs against human breast cancer MCF-7 cells was 1.9 times lower than that of DTX-micelles and DTX solution. DTX-NPs demonstrated 3.7- and 2.8-fold increase in the area under the plasma concentration-time curve compared with DTX-micelles after oral and parenteral administration, respectively.

High payload itraconazole-incorporated lipid nanoparticles with modulated release property for oral and parenteral administration

OBJECTIVES

The aim of this study was to develop high payload itraconazole-incorporated lipid nanoparticles (HINP) with modulated release property using a binary mixture core of solid and liquid lipid for oral and parenteral administration.

METHODS

High payload itraconazole-incorporated lipid nanoparticles were prepared by hot high-pressure homogenization method using tristearin (TS) as a solid lipid, triolein (TO) as a liquid lipid and egg phosphatidylcholine/Tween 80/DSPE-PEG₂₀₀₀ as a surfactants mixture. To investigate the effects of liquid lipid in lipid core on itraconazole (ITZ) dissolution and release, TS/TO ratio was varied as 100/0, 90/10 and 80/20 (mg/mg).

KEY FINDINGS

All HINP formulations showed particle size around 300 nm and polydispersity index below 0.3. The incorporation efficiencies of HINP formulations were above 80%, and more than 40 mg of ITZ was incorporated into each HINP formulation. In-vitro dissolution and release rate of ITZ from HINP increased as the amount of TO in lipid core increased. Compared with commercial formulations of ITZ, the pharmacokinetics of ITZ was improved after oral and parenteral administration of HINP formulations containing 0% or 10% of TO in lipid core.

CONCLUSION

High payload itraconazole-incorporated lipid nanoparticles with a binary mixture lipid core have a great potential for the development of controlled release formulation of ITZ.

Chitosan-based nanoparticles for improved anticancer efficacy and bioavailability of mifepristone

In addition to its well-known abortifacient effect, mifepristone (MIF) has been used as an anticancer drug for various cancers in many studies with an in-depth understanding of the mechanism of action. However, application of MIF is limited by its poor water solubility and low oral bioavailability. In this work, we developed a drug delivery system based on chitosan nanoparticles (CNs) to improve its bioavailability and anticancer activity. The MIF-loaded chitosan nanoparticles (MCNs) were prepared by convenient ionic gelation techniques between chitosan (Cs) and tripolyphosphate (TPP). The preparation conditions, including Cs concentration, TPP concentration, Cs/MIF mass ratio, and pH value of the TPP solution, were optimized to gain better encapsulation efficiency (EE) and drug loading capacity (DL). MCNs prepared with the optimum conditions resulted in spherical particles with an average size of 200 nm. FTIR and XRD spectra verified that MIF was successfully encapsulated in CNs. The EE and DL of MCNs determined by HPLC were 86.6% and 43.3%, respectively. The in vitro release kinetics demonstrated that MIF was released from CNs in a sustained-release manner. Compared with free MIF, MCNs demonstrated increased anticancer activity in several cancer cell lines. Pharmacokinetic studies in male rats that were orally administered MCNs showed a 3.2-fold increase in the area under the curve from 0 to 24 h compared with free MIF. These results demonstrated that MCNs could be developed as a potential delivery system for MIF to improve its anticancer activity and bioavailability.

Ivy leaves extract based – lipid nanocarriers and their bioefficacy on antioxidant and antitumor activities

Two issues were addressed in the paper: (1) the use of medicinal herbs as functional ingredients entrapped into lipid-based nanocarriers; (2) the efficacy of phytochemical-based nanocarriers with promising antioxidant and antitumor benefits.