Enhanced intestinal absorption of asenapine maleate by fabricating solid lipid nanoparticles using TPGS: elucidation of transport mechanism, permeability across Caco-2 cell line and in vivo pharmacokinetic studies

Enhanced bioavailability and efficacy in antimalarial treatment through QbD approach enteric encased inclusion delivery

Aim: In this study, we aimed to prepare enteric encapsulated spheroids containing inclusion complex using quality by design approach. Methods: A Box-Behnken design was employed to determine effects of variables on selected responses. Risk assessment was conducted using Ishikawa fishbone diagram. A model with a p-value was less than 0.5 for being a significant error of model was determined based on significance 'lack of fit' value. Spheroids were formulated using the extrusion spheronization technique and were characterized using analytical techniques. Results: In vitro release was performed in both acidic (pH 1.2) and simulated intestinal (pH 6.8) conditions. Permeability studies demonstrated tenfold enhancement compared with arteether. In vivo studies further validated increase of 51.8% oral bioavailability. Ex vivo studies revealed 3.4-fold enhancement in antimalarial activity compared with arteether. Conclusion: These findings highlight effectiveness of inclusion complexation technique as a viable approach to enhance solubility and bioavailability for drugs with low aqueous solubility.

Evaluation of Silybin Nanoparticles against Liver Damage in Murine Schistosomiasis mansoni Infection

Silybin (SIB) is a hepatoprotective drug known for its poor oral bioavailability, attributed to its classification as a class IV drug with significant metabolism during the first-pass effect. This study explored the potential of solid lipid nanoparticles with (SLN-SIB-U) or without (SLN-SIB) ursodeoxycholic acid and polymeric nanoparticles (PN-SIB) as delivery systems for SIB. The efficacy of these nanosystems was assessed through in vitro studies using the GRX and Caco-2 cell lines for permeability and proliferation assays, respectively, as well as in vivo experiments employing a murine model of Schistosomiasis mansoni infection in BALB/c mice. The mean diameter and encapsulation efficiency of the nanosystems were as follows: SLN-SIB (252.8 ± 4.4 nm, 90.28 ± 2.2%), SLN-SIB-U (252.9 ± 14.4 nm, 77.05 ± 2.8%), and PN-SIB (241.8 ± 4.1 nm, 98.0 ± 0.2%). In the proliferation assay with the GRX cell line, SLN-SIB and SLN-SIB-U exhibited inhibitory effects of 43.09 ± 5.74% and 38.78 ± 3.78%, respectively, compared to PN-SIB, which showed no inhibitory effect. Moreover, SLN-SIB-U demonstrated a greater apparent permeability coefficient (25.82 ± 2.2) than PN-SIB (20.76 ± 0.1), which was twice as high as that of SLN-SIB (11.32 ± 4.6) and pure SIB (11.28 ± 0.2). These findings suggest that solid lipid nanosystems hold promise for further in vivo investigations. In the murine model of acute-phase Schistosomiasis mansoni infection, both SLN-SIB and SLN-SIB-U displayed hepatoprotective effects, as evidenced by lower alanine amino transferase values (22.89 ± 1.6 and 23.93 ± 2.4 U/L, respectively) than those in control groups I (29.55 ± 0.7 U/L) and I+SIB (34.29 ± 0.3 U/L). Among the prepared nanosystems, SLN-SIB-U emerges as a promising candidate for enhancing the pharmacokinetic properties of SIB.

Zein-based nanospheres and nanocapsules for the encapsulation and oral delivery of quercetin

In this study, the ability of zein nanospheres (NS) and zein nanocapsules containing wheat germ oil (NC) to enhance the bioavailability and efficacy of quercetin was evaluated. Both types of nanocarriers had similar physico-chemical properties, including size (between 230 and 250 nm), spherical shape, negative zeta potential, and surface hydrophobicity. However, NS displayed a higher ability than NC to interact with the intestinal epithelium, as evidenced by an oral biodistribution study in rats. Moreover, both types of nanocarriers offered similar loading efficiencies and release profiles in simulated fluids. In C. elegans, the encapsulation of quercetin in nanospheres (Q-NS) was found to be two twice more effective than the free form of quercetin in reducing lipid accumulation. For nanocapsules, the presence of wheat germ oil significantly increased the storage of lipids in C. elegans; although the incorporation of quercetin (Q-NC) significantly counteracted the presence of the oil. Finally, nanoparticles improved the oral absorption of quercetin in Wistar rats, offering a relative oral bioavailability of 26% and 57% for Q-NS and Q-NC, respectively, compared to a 5% for the control formulation. Overall, the study suggests that zein nanocarriers, particularly nanospheres, could be useful in improving the bioavailability and efficacy of quercetin.

Research Progress on the Mechanism of Nanoparticles Crossing the Intestinal Epithelial Cell Membrane

Improving the stability of drugs in the gastrointestinal tract and their penetration ability in the mucosal layer by implementing a nanoparticle delivery strategy is currently a research focus in the pharmaceutical field. However, for most drugs, nanoparticles failed in enhancing their oral absorption on a large scale (4 folds or above), which hinders their clinical application. Recently, several researchers have proved that the intestinal epithelial cell membrane crossing behaviors of nanoparticles deeply influenced their oral absorption, and relevant reviews were rare. In this paper, we systematically review the behaviors of nanoparticles in the intestinal epithelial cell membrane and mainly focus on their intracellular mechanism. The three key complex intracellular processes of nanoparticles are described: uptake by intestinal epithelial cells on the apical side, intracellular transport and basal side exocytosis. We believe that this review will help scientists understand the in vivo performance of nanoparticles in the intestinal epithelial cell membrane and assist in the design of novel strategies for further improving the bioavailability of nanoparticles.

Amalgamation of solid dispersion and melt adsorption techniques for augmentation of oral bioavailability of novel anticoagulant rivaroxaban

The objective of the present study was to evaluate the potential of solid dispersion adsorbate (SDA) to improve the solubility and bioavailability of rivaroxaban (RXN). SDA of RXN was developed by fusion method using PEG 4000 as carrier and Neusilin as adsorbent. A 3² full factorial design was utilized to formulate various SDAs. The selected independent variables were the amount of carrier (X₁) and amount of adsorbent (X₂). The responses measured were the time required for 85% drug release (Y₁) and saturated solubility (Y₂). MTT assay was employed for cytotoxicity studies on Caco-2 cells. In vivo pharmacokinetics and pharmacodynamic evaluations were carried out to assess the prepared SDA. Pre-compression evaluation of SDA suggests the prepared batches (B1-B9) possess adequate flow properties and could be used for compression of tablets. Differential scanning calorimetry and X-ray diffraction data signified the conversion of the crystalline form of drug to amorphous form, a key parameter accountable for improvement in drug dissolution. Optimization data suggests that the amount of carrier and amount of adsorbent significantly (P < 0.05) influence both dependent variables. Post-compression data signifies that the compressibility behavior of prepared tablets was within the official standard limits. A significant increase (P < 0.0001) in the in vitro dissolution characteristics of RXN was noticed in optimized SDA (> 85% in 10 min) as compared to the pure drug, marketed product, and directly compressible tablet. Cytotoxicity studies confirmed the nontoxicity of prepared RXN SDA tablets. RXN SDA tablets exhibited 2.79- and 1.85-fold higher AUC in comparison to RXN suspension and Xarelto tablets respectively indicating improved oral bioavailability. Higher bleeding time and percentage of platelet aggregation noticed with RXN SDA tablets in comparison to RXN suspension further substantiate the efficacy of the prepared formulation. In summary, the results showed the potential of RXN SDA tablets to enhance the bioavailability of RXN and hence can be an alternate approach of solid dosage form for its development for commercial application.

Kaurenoic acid nanocarriers regulates cytokine production and inhibit breast cancer cell migration

Breast cancer is the type of cancer with the highest incidence in women around the world. Noteworthy, the triple-negative subtype affects 20% of the patients while presenting the highest death rate among subtypes. This is due to its aggressive phenotype and the capability of invading other tissues. In general, tumor-associated macrophages (TAM) and other immune cells, are responsible for maintaining a favorable tumor microenvironment for inflammation and metastasis by secreting several mediators such as pro-inflammatory cytokines IL-1β, IL-6, and TNF-α, chemokines like CCL2, and other proteins, as metalloproteinases of matrix (MMP). On the other hand, immunomodulatory agents can interfere in the immune response of TAM and change the disease prognosis. In this work, we prepared nanostructured lipid carriers containing kaurenoic acid (NLC-KA) to evaluate the effect on cytokine production in vitro of bone marrow-derived macrophages (BMDM) and the migratory process of 4 T1 breast cancer cells. NLC-KA prepared from a blend of natural lipids was shown to have approximately 90 nm in diameter with low polydispersity index. To test the effect on cytokine production in vitro in NLC-KA treated BMDM, ELISA assay was performed and pro-inflammatory cytokines IL-1β, IL-6, and TNF-α were quantified. The formulation reduced the secretion of IL-1β and TNF-α cytokines while presenting no hemolytic activity. Noteworthy, an anti-migratory effect in 4 T1 breast cancer cells treated with NLC-KA was observed in scratch assays. Further, MMP9 and CCL2 gene expressions in both BMDM and 4 T1 treated cells confirmed that the mechanism of inhibition of migration is related to the blockade of this pathway by KA. Finally, cell invasion assays confirmed that NLC-KA treatment resulted in less invasiveness of 4 T1 cells than control, and it is independent of CCL2 stimulus or BMDM direct stimulus. Ultimately, NLC-KA was able to regulate the cytokine production in vitro and reduce the migration of 4 T1 breast cancer cells by decreasing MMP9 gene expression.

Improved uptake and bioavailability of cinnamaldehyde via solid lipid nanoparticles for oral delivery

OBJECTIVE

The purpose of this experiment was to explore the effect of Solid lipid nanoparticles (SLNs) on improving the oral absorption and bioavailability of cinnamaldehyde (CA).

METHODS

CA-SLNs were prepared by high-pressure homogenization and characterized by particle size, entrapment efficiency, and morphology, thermal behavior and attenuated total reflection Fourier transform infrared (ATR-FTIR). In vitro characteristics of release, stability experiments, cytotoxicity, uptake and transport across Caco-2 cell monolayer of CA-SLNs were studied as well. In addition, CA-SLNs underwent pharmacokinetic and gastrointestinal mucosal irritation studies in rats.

RESULTS

CA-SLNs exhibited a spherical shape with a particle size of 44.57 ± 0.27 nm, zeta potential of -27.66 ± 1.9 mV and entrapment efficiency of 83.63% ± 2.16%. Differential scanning calorimetry (DSC) and ATR-FTIR confirmed that CA was well encapsulated. In vitro release of CA-SLNs displayed that most of the drug (90.77% ± 5%) was released in the phosphate buffer, and only a small amount of drug (18.55% ± 5%) was released in the HCl buffer. CA-SLNs were taken up by an energy-dependent, endocytic mechanism mediated by caveolae mediated endocytosis across Caco-2 cells. The CA permeation through Caco-2 cell was facilitated by CA-SLNs. The outcome of the gastrointestinal irritation test demonstrated that CA-SLNs had no irritation to the rats' intestines. Compared with CA dispersions, incorporation of SLNs increased the oral bioavailability of CA more than 1.69-fold.

CONCLUSIONS

It was concluded that CA-SLNs improved the absorption across Caco-2 cell model and improved the oral administration bioavailability of CA in rats.

Novel Phenobarbital-Loaded Nanostructured Lipid Carriers for Epilepsy Treatment: From QbD to In Vivo Evaluation

Pharmacological treatments of central nervous system diseases are always challenging due to the restrictions imposed by the blood–brain barrier: while some drugs can effectively cross it, many others, some antiepileptic drugs among them, display permeability issues to reach the site of action and exert their pharmacological effects. The development of last-generation therapeutic nanosystems capable of enhancing drug biodistribution has gained ground in the past few years. Lipid-based nanoparticles are promising systems aimed to improve or facilitate the passage of drugs through biological barriers, which have demonstrated their effectiveness in various therapeutic fields, without signs of associated toxicity. In the present work, nanostructured lipid carriers (NLCs) containing the antiepileptic drug phenobarbital were designed and optimized by a quality by design approach (QbD). The optimized formulation was characterized by its entrapment efficiency, particle size, polydispersity index, and Z potential. Thermal properties were analyzed by DSC and TGA, and morphology and crystal properties were analyzed by AFM, TEM, and XRD. Drug localization and possible interactions between the drug and the formulation components were evaluated using FTIR. In vitro release kinetic, cytotoxicity on non-tumoral mouse fibroblasts L929, and in vivo anticonvulsant activity in an animal model of acute seizures were studied as well. The optimized formulation resulted in spherical particles with a mean size of ca. 178 nm and 98.2% of entrapment efficiency, physically stable for more than a month. Results obtained from the physicochemical and in vitro release characterization suggested that the drug was incorporated into the lipid matrix losing its crystalline structure after the synthesis process and was then released following a slower kinetic in comparison with the conventional immediate-release formulation. The NLC was non-toxic against the selected cell line and capable of delivering the drug to the site of action in an adequate amount and time for therapeutic effects, with no appreciable neurotoxicity. Therefore, the developed system represents a promising alternative for the treatment of one of the most prevalent neurological diseases, epilepsy.

Intestinal Absorption Study: Challenges and Absorption Enhancement Strategies in Improving Oral Drug Delivery

The oral route is the most common and practical means of drug administration, particularly from a patient’s perspective. However, the pharmacokinetic profile of oral drugs depends on the rate of drug absorption through the intestinal wall before entering the systemic circulation. However, the enteric epithelium represents one of the major limiting steps for drug absorption, due to the presence of efflux transporters on the intestinal membrane, mucous layer, enzymatic degradation, and the existence of tight junctions along the intestinal linings. These challenges are more noticeable for hydrophilic drugs, high molecular weight drugs, and drugs that are substrates of the efflux transporters. Another challenge faced by oral drug delivery is the presence of first-pass hepatic metabolism that can result in reduced drug bioavailability. Over the years, a wide range of compounds have been investigated for their permeation-enhancing effect in order to circumvent these challenges. There is also a growing interest in developing nanocarrier-based formulation strategies to enhance the drug absorption. Therefore, this review aims to provide an overview of the challenges faced by oral drug delivery and selected strategies to enhance the oral drug absorption, including the application of absorption enhancers and nanocarrier-based formulations based on in vitro, in vivo, and in situ studies.

Development of Self-Microemulsifying Drug Delivery System to Improve Nisoldipine Bioavailability: Cell Line and In Vivo Evaluations : Development of Self-Microemulsifying Drug Delivery System

The authors attempted to fabricate a novel lipid-based formulation of a lipophilic drug, nisoldipine (NISO). As NISO belongs to BCS class 2 drug, it suffers from low bioavailability (5%). Hence, the research was intended to ameliorate oral bioavailability of NISO via intestinal lymphatic transport. The NISO loaded self microemulsifying drug delivery system (SMEDDS) (NISO SMEDDS) was prepared using Peceol, Cremophor EL, and Transcutol HP. The Cremophor EL and Transcutol HP at 1:1 ratio showed maximum microemulsifying area, and average globule size was 16.78 ± 0.97 nm with PDI 0.121 ± 0.024. Cellular uptake studies (confocal microscopy and flow cytometry) using Caco-2 cells depicted higher fluorescence with coumarin-6 loaded SMEDDS as that of coumarin-6 solution which indicated deeper penetration. Mean fluorescence intensity (MFI) of coumarin-6 loaded SMEDDS was significantly improved (9.92-fold) in contrast to coumarin-6 solution. The NISO SMEDDS showed enhanced permeability (5.02 times) across Caco-2 cells compared to NISO suspension. The bioavailability improvement with NISO SMEEDS was 2.14 times relative to suspension, and lymphatic uptake was involved in oral absorption of NISO SMEDDS.

Development and Optimization of Asenapine Sublingual Film Using QbD Approach

Asenapine, an atypical antipsychotic agent, has been approved for the acute and maintenance treatment of schizophrenia and manic episodes of bipolar disorder. However, the extensive hepatic metabolism limits its oral bioavailability. Therefore, the objective of the current investigation was to develop sublingual film containing asenapine to enhance the therapeutic efficacy. Sublingual films containing asenapine were fabricated using polyethylene oxide and hydroxypropyl methylcellulose by solvent casting method. Design of experiment was used as a statistical tool to optimize the proportion of the film-forming polymers in order to establish the critical quality attributes of the drug formulation. The process was studied in detail by assessing risk of each step as well as parameters and material attributes to reduce the risk to a minimum. A control strategy was defined to ensure manufacture of films according to the target product profile by evaluation of intermediate quality attributes at the end of each process step. Results of optimized formulations showed rapid disintegration, adequate folding endurance, good percentage elongation, tensile strength, and viscosity. Besides, the results from the in vitro dissolution/ex vivo permeation studies showed rapid dissolution (100% in 6 min) and higher asenapine permeation (~ 80% in 90 min) through the sublingual epithelium. In vivo study indicates greater asenapine absorption (31.18 ± 5.01% of administered dose) within 5 min and was comparable with marketed formulation. In summary, the designing plan to develop asenapine formulation was successfully achieved with desired characteristics of the delivery tool for sublingual administration.

Applications of innovative technologies to the delivery of antipsychotics

Psychosis is a high-incidence pathology associated with a profound alteration in the perception of reality. The limitations of drugs available on the market have stimulated the search for alternative solutions to achieve effective antipsychotic therapies. In this review, we evaluate innovative formulations of antipsychotic drugs developed through the application of modern pharmaceutical technologies, including classes of micro and nanocarriers, such as lipid formulations, polymeric nanoparticles (NPs), solid dispersions, and cyclodextrins (CDs). We also consider alternative routes of administration to the oral and parenteral ones currently used. Improved solubility, stability of preparations, and pharmacokinetic (PK) and pharmacodynamic (PD) parameters confirm the potential of these new formulations in the treatment of psychotic disorders.

Nanoparticulate Drug Delivery Strategies to Address Intestinal Cytochrome P450 CYP3A4 Metabolism towards Personalized Medicine

Drug dosing in clinical practice, which determines optimal efficacy, toxicity or ineffectiveness, is critical to patients' outcomes. However, many orally administered therapeutic drugs are susceptible to biotransformation by a group of important oxidative enzymes, known as cytochrome P450s (CYPs). In particular, CYP3A4 is a low specificity isoenzyme of the CYPs family, which contributes to the metabolism of approximately 50% of all marketed drugs. Induction or inhibition of CYP3A4 activity results in the varied oral bioavailability and unwanted drug-drug, drug-food, and drug-herb interactions. This review explores the need for addressing intestinal CYP3A4 metabolism and investigates the opportunities to incorporate lipid-based oral drug delivery to enable precise dosing. A variety of lipid- and lipid-polymer hybrid-nanoparticles are highlighted to improve drug bioavailability. These drug carriers are designed to target different intestinal regions, including (1) local saturation or inhibition of CYP3A4 activity at duodenum and proximal jejunum; (2) CYP3A4 bypass via lymphatic absorption; (3) pH-responsive drug release or vitamin-B12 targeted cellular uptake in the distal intestine. Exploitation of lipidic nanosystems not only revives drugs removed from clinical practice due to serious drug-drug interactions, but also provide alternative approaches to reduce pharmacokinetic variability.

Determination of Asenapine Maleate in Pharmaceutical and Biological Matrices: A Critical Review of Analytical Techniques over the Past Decade

Asenapine maleate is a second-generation atypical antipsychotic agent used in the treatment of schizophrenia, a neuropsychiatric disorder. It is available as a fast-dissolving sublingual tablet to avoid extensive first-pass metabolism with higher bioavailability as compared to oral formulations. Although, the established therapeutic solutions do not sufficiently satisfy the patient's safety and efficacy needs. Thus, the core research emphasis is to investigate strategies to produce novel formulations with enhanced safety and efficacy. This necessitates the development of robust, precise, and accurate methods for quantification of asenapine maleate in different sample matrices. Given the foregoing information, the current analysis concentrates on the different analytical techniques used to assess asenapine maleate in bulk, pharmaceutical formulations, and biological specimens. Reverse-phase HPLC coupled with UV detection is a majorly (nearly 50% of papers investigated) used technique for the estimation of asenapine maleate in formulations. On the other hand, for its quantification in the biological matrix, hyphenated techniques using mass spectrometry are widely used. This critical review reveals different analytical methodologies, including spectrophotometric, chromatographic, capillary electrophoresis techniques reported from 2011 to 2020, for the measurement of asenapine maleate in various sample matrices. The information presented in this review would be useful in future research for robust analytical method development for asenapine maleate utilizing a more scientific and risk-based approach. Also, it would aid to minimize analytical failure as well as method fine-tuning throughout the product life cycle. Further, this review may also direct scientists toward the development of methodologies for green research.

Solid Lipid Nanoparticles for Drug Delivery: Pharmacological and Biopharmaceutical Aspects

In the golden age of pharmaceutical nanocarriers, we are witnessing a maturation stage of the original concepts and ideas. There is no doubt that nanoformulations are extremely valuable tools for drug delivery applications; the current challenge is how to optimize them to ensure that they are safe, effective and scalable, so that they can be manufactured at an industrial level and advance to clinical use. In this context, lipid nanoparticles have gained ground, since they are generally regarded as non-toxic, biocompatible and easy-to-produce formulations. Pharmaceutical applications of lipid nanocarriers are a burgeoning field for the transport and delivery of a diversity of therapeutic agents, from biotechnological products to small drug molecules. This review starts with a brief overview of the characteristics of solid lipid nanoparticles and discusses the relevancy of performing systematic preformulation studies. The main applications, as well as the advantages that this type of nanovehicles offers in certain therapeutic scenarios are discussed. Next, pharmacokinetic aspects are described, such as routes of administration, absorption after oral administration, distribution in the organism (including brain penetration) and elimination processes. Safety and toxicity issues are also addressed. Our work presents an original point of view, addressing the biopharmaceutical aspects of these nanovehicles by means of descriptive statistics of the state-of-the-art of solid lipid nanoparticles research. All the presented results, trends, graphs and discussions are based in a systematic (and reproducible) bibliographic search that considered only original papers in the subject, covering a 7 years range (2013-today), a period that accounts for more than 60% of the total number of publications in the topic in the main bibliographic databases and search engines. Focus was placed on the therapeutic fields of application, absorption and distribution processes and current efforts for the translation into the clinical practice of lipid-based nanoparticles. For this, the currently active clinical trials on lipid nanoparticles were reviewed, with a brief discussion on what achievements or milestones are still to be reached, as a way of understanding the reasons for the scarce number of solid lipid nanoparticles undergoing clinical trials.

Recent advances in the development of asenapine formulations

INTRODUCTION

Asenapine maleate (AM) is an atypical antipsychotic agent, that has been widely prescribed for the management of schizoaffective disorders. However, the bioavailability of AM is extremely poor due to the extensive first-pass metabolism. With the advancement in pharmaceutical technologies, significant strides have been made to create novel formulations to address the bioavailability problem of AM.

AREAS COVERED

This review article provides an insight into all the formulation approaches undertaken by researchers to increase the bioavailability of AM encompassing the works utilizing ultrasound mediated transdermal delivery, nose to brain delivery, intestinal lymphatic system targeting, in situ implants, etc. All the patents associated with AM formulation have also been discussed and summarized.

EXPERT OPINION

Numerous studies have been carried out on AM formulations over the recent years, many of these studies have shown significant improvement in bioavailability. We have also mentioned the unexplored domains which can be exploited for further enhancing the bioavailability of AM. Nonetheless, most of these studies are still limited to the research laboratory level and face multiple hurdles before making into the market. Attaining controllability and reproducibility for the production of novel formulations is needed to enable its transition from bench to bedside.

Screening of nanoemulsion components for asenapine maleate using validated RP-HPLC method

A novel, simple reversed-phase high-performance liquid chromatographic (RP-HPLC) analytical method was developed and validated for the quantitative determination of asenapine from various nanoemulsion components during pre-formulation screening. The developed method was validated according to ICH Q2 (R1) guidelines. The developed and validated method was precisely and accurately quantified asenapine in various oils, surfactants and co-surfactants. The separation of asenapine was carried out on Hypersil BDS C18, 250×4.6mm, 5μm particle size column using methanol: acetonitrile (90:10) as mobile phase with a flow rate of 1mL.min^-1. Measurement at 270nm for the concentration range of 5 to 50μg.mL^-1 of the analyte was found to be linear with the determination coefficient (r²) of 0.999 as calculated by the least square regression method. The validated method was sensitive with LOD of 10.0ng.mL^-1 and LOQ of 30.0ng.mL^-1. Further, the method was precise and accurate, where the intraday and interday precision values were ranged from 0.70-0.95 and 0.36-0.95, respectively with the corresponding accuracy were ranged from 98.80-100.63 and 98.36-100.63. This developed and validated RP-HPLC method for asenapine was applied in the quantitative determination and screening of various oils, surfactants, and co-surfactants during the development of the asenapine maleate nanoemulsion.

Nanoformulation strategies for improving intestinal permeability of drugs: A more precise look at permeability assessment methods and pharmacokinetic properties changes

The therapeutic efficacy of orally administered drugs is often restricted by their inherent limited oral bioavailability. Low water solubility, limited permeability through the intestinal barrier, instability in harsh environment of the gastrointestinal (GI) tract and being substrate of the efflux pumps and the cytochrome P450 (CYP) can impair oral drug bioavailability resulting in erratic and variable plasma drug profile. As more drugs with low membrane permeability are developed, new interest is growing to enhance their intestinal permeability and bioavailability. A wide variety of nanosystems have been developed to improve drug transport and absorption. Sufficient evidence exists to suggest that nanoparticles are able to increase the transepithelial transport of drug molecules. However, key questions remained unanswered. What types of nanoparticles are more efficient? What are preclinical (or clinical) achievements of each type of nanoformulation in terms of pharmacokinetic (PK) parameters? Addressing this issue in this paper, we have reviewed the current literature regarding permeability enhancement, permeability assessment methods and changes in PK parameters following administration of various nanoformulations. Although permeability enhancement by various nanoformulations holds great promise for oral drug delivery, many challenges still need to be addressed before development of more clinically successful nanoproducts.

Evaluation of Intestinal Absorption Mechanism and Pharmacokinetics of Curcumin-Loaded Galactosylated Albumin Nanoparticles

Background

Most of the oral drugs have the properties of weak intestinal absorption and low bioavailability, which leads to little treatment to diseases. By nanotechnology, these drugs can be efficiently delivered to pass biological barriers and promote the cell uptake ability for the enhancement of the oral bioavailability.

Methods

The present work chose the prepared curcumin-loaded galactosylated albumin nanoparticles (Gal-BSA NPs) as the nano-drug samples to study the intestinal capacity and the oral bioavailability.

Results

The cell uptake assay showed that the Gal-BSA NPs could promote the internalization of more curcumin into the Caco-2 cells. Moreover, the cell uptake mechanism of Gal-BSA-Cur NPs depended on the clathrin-mediated endocytosis transport. The intestinal permeation assay using one Ussing chamber exhibited that the absorptive amounts of curcumin in Gal-BSA-Cur NPs group were 1.5-fold of pure curcumin group. Meanwhile, the permeation mechanism of Gal-BSA-Cur NPs across the intestine mainly depended on the passive transport. The pharmacokinetics study in vivo suggested that the oral bioavailability of Gal-BSA-Cur NPs was improved by 1.4-fold compared with pure curcumin.

Conclusion

All results demonstrated that Gal-BSA NPs could improve the intestinal absorption capacity and oral bioavailability of curcumin through the double absorption mechanisms of the clathrin-mediated endocytosis and the passive transport.

Nanoparticles for antiparasitic drug delivery

As an emerging novel drug carrier, nanoparticles provide a promising way for effective treatment of parasitic diseases by overcoming the shortcomings of low bioavailability, poor cellular permeability, nonspecific distribution and rapid elimination of antiparasitic drugs from the body. In recent years, some kinds of ideal nanocarriers have been developed for antiparasitic drug delivery. In this review, the progress of the enhanced antiparasitic effects of different nanoparticles payload and their influencing factors were firstly summarized. Secondly, the transport and disposition process in the body were reviewed. Finally, the challenges and prospects of nanoparticles for antiparasitic drug delivery were proposed. This review will help scholars to understand the development trend of nanoparticles in the treatment of parasitic diseases and explore strategies in the development of more efficient nanocarriers to overcome the difficulty in the treatment of parasite infections in the future.

Self microemulsifying drug delivery system of lurasidone hydrochloride for enhanced oral bioavailability by lymphatic targeting: In vitro, Caco-2 cell line and in vivo evaluation

The global aim of this research was to develop and evaluate self-microemulsifying drug delivery system (SMEDDS) to improve oral bioavailability of Lurasidone Hydrochloride (LH). A chylomicron flow blocking approach was used to evaluate lymphatic drug transport. The developed LH-SMEDDS was composed of Capmul MCM C8 (oil), Cremophor EL (surfactant) and Transcutol HP (co-surfactant). Highest microemulsifying area was obtained at 3:1 ratio (surfactant:cosurfactant) and mean globule size was found to be 49.22 ± 1.60 nm. More than 98% drug release was obtained with LH-SMEDDS in phosphate buffer pH 6.8. Confocal microscopy and flow cytometry studies revealed higher fluorescence indicating deeper penetration across Caco-2 cells with Coumarin-6 SMEDDS as compared to Coumarin-6 solution. Mean Fluorescence Intensity (MFI) with Coumarin-6 loaded SMEDDS was increased 25.57 times with respect to Coumarin-6 solution. The permeability across Caco-2 cells was enhanced 3 times with LH-SMEDDS as compared to LH-suspension. Furthermore, Area Under Curve with LH-SMEDDS was found to be 2.92 times higher than that of LH suspension indicating improved bioavailability after formulating SMEDDS. Lymphatic transport in oral absorption of LH-SMEDDS was proved via lymphatic uptake study. All the findings suggest the effectiveness of lipid-based formulation i.e. SMEDDS of LH to augment the oral bioavailability via intestinal lymphatic pathway.

Anti-Angiogenic Effect of Orally Available Pemetrexed for Metronomic Chemotherapy

Metronomic chemotherapy (MCT) is defined as the frequent administration of low-dose chemotherapeutics, without long drug-free periods, with the exertion of antitumor activity exclusively through anti-angiogenic mechanisms. In this study, we have developed an orally available formulation of pemetrexed (PMX) for MCT. PMX was first complexed ionically with N^α-deoxycholyl-l-lysyl-methylester (DCK) as the permeation enhancer. This was followed by dispersion with poloxamer 188 and Labrasol to form the solid oral formulation of PMX (PMX/DCK-OP). PMX/DCK-OP exhibited a 10.6-fold increase in permeability across a Caco-2 cell monolayer compared to PMX alone. This resulted in a 70-fold increase in the oral bioavailability of PMX/DCK-OP in mice over oral PMX alone. In the A549 xenograft model, tumor volume was reduced by 51.1% in the PMX/DCK-OP treated group compared to only 32.8% in the maximum tolerated dose (MTD)-treated group. Furthermore, PMX/DCK-OP exhibited a significant anti-angiogenic effect on the A549 xenograft mice when compared to the MTD-treated group, as indicated by microvessel density quantification for CD-31. In addition, PMX/DCK-OP enhanced the release of an endogenous angiogenesis inhibitor, thrombospondin-1 (TSP-1), into both the blood circulation and the tumor microenvironment. Therefore, due to its oral route of administration, PMX/DCK-OP appears to be a better alternative to the conventional treatment of PMX.

Biological fate of ingested lipid-based nanoparticles: current understanding and future directions

In recent decades, lipid-based nanoparticles (LN) have received considerable attention as nanoscale delivery systems to improve oral bioavailability of poorly absorbed bioactive compounds for health promotion and disease prevention. However, scientific studies on the biological fate of orally administered LN are very limited and the molecular mechanisms by which they are absorbed through the intestinal lumen into the circulation remain unclear. This paper aims to provide an overview of the biological fate of orally administered LN by reviewing recent studies on both cell and animal models. In general, the biological fate of ingested LN in the gastrointestinal tract is primarily determined by their initial physicochemical characteristics (such as the particle size, surface properties, composition and structure), and their absorption mainly occurs within the small intestine. In particular, depending upon the composition, LN can be either digestible or indigestible, with two distinct biological fates for each type of LN. The detailed absorption mechanisms and uptake pathways at molecular, cellular and whole body levels for each type of LN are discussed in detail. Limitations of current research and our vision for future directions to study the biological fate of ingested LN are also provided in this critical review.