Development and evaluation of olanzapine-loaded PLGA nanoparticles for nose-to-brain delivery: in vitro and in vivo studies

The Role of Cell-Penetrating Peptide and Transferrin on Enhanced Delivery of Drug to Brain

The challenge of effectively delivering therapeutic agents to brain has led to an entire field of active research devoted to overcome the blood brain barrier (BBB) and efficiently deliver drugs to brain. This review focusses on exploring the facets of a novel platform designed for the delivery of drugs to brain. The platform was constructed based on the hypothesis that a combination of receptor-targeting agent, like transferrin protein, and a cell-penetrating peptide (CPP) will enhance the delivery of associated therapeutic cargo across the BBB. The combination of these two agents in a delivery vehicle has shown significantly improved (p < 0.05) translocation of small molecules and genes into brain as compared to the vehicle with only receptor-targeting agents. The comprehensive details of the uptake mechanisms and properties of various CPPs are illustrated here. The application of this technology, in conjunction with nanotechnology, can potentially open new horizons for the treatment of central nervous system disorders.

Plant extracts: from encapsulation to application

INTRODUCTION

Plants are a natural source of various products with diverse biological activities offering treatment for several diseases. Plant extract is a complex mixture of compounds, which can have antioxidant, antibiotic, antiviral, anticancer, antiparasitic, antifungal, hypoglycemic, anti-hypertensive and insecticide properties. The extraction of these extracts requires the use of organic solvents, which not only complicates the formulations but also makes it difficult to directly use the extracts for humans. To overcome these problems, recent research has been focused on developing new ways to formulate the plant extracts and delivering them safely with enhanced therapeutic efficacy.

AREAS COVERED

This review focuses on the research done in the development and use of polymeric nanoparticles for the encapsulation and administration of plant extracts. It describes in detail, the different encapsulation techniques, main physicochemical characteristics of the nanoparticles, toxicity tests and results obtained from in vivo or in vitro assays.

EXPERT OPINION

Major obstacles associated with the use of plant extracts for clinical applications include their complex composition, toxicity risks and extract instability. It is observed that encapsulation can be successfully used to decrease plant extracts toxicity, to provide targeted drug delivery and to solve stability related problems.

Trans-nasal zolmitriptan novasomes: in-vitro preparation, optimization and in-vivo evaluation of brain targeting efficiency

Migraine attack is a troublesome physiological condition associated with throbbing, intense headache, in one half of the head. Zolmitriptan is a potent second-generation triptan, prescribed for patients with migraine attacks, with or without an aura, and cluster headaches. The absolute bioavailability of zolmitriptan is about 40% for oral administration; due to hepatic first metabolism. Nasal administration would circumvent the pre-systemic metabolism thus increasing the bioavailability of zolmitriptan. In addition, due to the presence of microvilli and high vasculature, the absorption is expected to be faster compared to oral route. However, the bioavailability of nasal administered drugs is particularly restricted by poor membrane penetration. Thus, the aim of this work is to explore the potential of novel nanovesicular fatty acid enriched structures (novasomes) for effective and enhanced nasal delivery of zolmitriptan and investigate their nose to brain targeting potential. Novasomes were prepared using nonionic surfactant, cholesterol in addition to a free fatty acid. A 2³ full factorial design was adopted to study the influence of the type of surfactant, type of free fatty acid and ratio between the free fatty acid and the surfactant on novasomes properties. The particle size, entrapment efficiency, polydispersity index, zeta potential and % zolmitriptan released after 2 h were selected as dependent variables. Novasomes were further optimized using Design Expert® software (version 7; Stat-Ease Inc., Minneapolis, MN), and an optimized formulation composed of Span® 80:Cholesterol:stearic acid (in the ratio 1:1:1) was selected. This formulation showed zolmitriptan entrapment of 92.94%, particle size of 149.9 nm, zeta potential of -55.57 mV, and released 48.43% zolmitriptan after 2 h. The optimized formulation was further examined using transmission electron microscope, which revealed non-aggregating multi-lamellar nanovesicles with narrow size distribution. DSC, XRD examination of the optimized formulation confirmed that the drug have been homogeneously dispersed throughout the novasomes in an amorphous state. In-vivo bio-distribution studies of ^99mTc radio-labeled intranasal zolmitriptan loaded novasomes were done on mice, the pharmacokinetic parameters were compared with those following administration of intravenous ^99mTc-zolmitriptan solution. Results revealed the great enhancement in zolmitriptan targeting to the brain, with drug targeting potential of about 99% following intranasal administration of novasomes compared with the intravenous drug solution. Zolmitriptan loaded novasomes administered via the nasal route may therefore constitute an advance in the management of acute migraine attacks.

Intranasal delivery of nanoparticle encapsulated tarenflurbil: A potential brain targeting strategy for Alzheimer's disease

Poor brain penetration of tarenflurbil (TFB) was one of the major reasons for its failure in phase III clinical trials conducted on Alzheimer's patients. Thus there is a tremendous need of developing efficient delivery systems for TFB. This study was designed with the aim of improving drug delivery to brain through intranasally delivered nanocarriers. TFB was loaded into two different nanocarriers i.e., poly (lactide-co-glycolide) nanoparticles (TFB-NPs) and solid lipid nanoparticles (TFB-SLNs). Particle size of both the nanocarriers (<200nm) as determined by dynamic light scattering technique and transmission electron microscopy, assured transcellular transport across olfactory axons whose diameter was ≈200nm and then paving a direct path to brain. TFB-NPs and TFB-SLNs resulted in 64.11±2.21% and 57.81±5.32% entrapment efficiencies respectively which again asserted protection of drug from chemical and biological degradation in nasal cavity. In vitro release studies proved the sustained release of TFB from TFB-NPs and TFB-SLNs in comparison with pure drug, indicating prolonged residence times of drug at targeting site. Pharmacokinetics suggested improved circulation behavior of nanoparticles and the absolute bioavailabilities followed this order: TFB-NPs (i.n.)>TFB-SLNs (i.n.)>TFB solution (i.n.)>TFB suspension (oral). Brain targeting efficiency was determined in terms of %drug targeting efficiency (%DTE) and drug transport percentage (DTP). The higher %DTE (287.24) and DTP (65.18) were observed for TFB-NPs followed by TFB-SLNs (%DTE: 183.15 and DTP: 45.41) among all other tested groups. These encouraging results proved that therapeutic concentrations of TFB could be transported directly to brain via olfactory pathway after intranasal administration of polymeric and lipidic nanoparticles.

Enhanced brain targeting efficacy of Olanzapine through solid lipid nanoparticles

Olanzapine (OLZ) is a typical anti-psychotic drug, which is highly lipophilic in nature, belongs to Biopharmaceutical Classification System (BCS) class II category. Though OLZ is an effective agent in the treatment of Schizophrenia, but it exhibits poor bioavailability (57%) due to extensive first-pass metabolism resulted in high dose is required to achieve therapeutic concentration in brain. Emerging evidences are indicating that high dose administration of OLZ may cause Extrapyramidal symptoms (EPS) in the psychotic patients. Hence, the present study is designed to develop Olanzapine solid lipid (OLZ-SLNs) using minimal dose of OLZ thereby enhancing the brain efficacy as well as to reduce the side effects associated with OLZ. OLZ-SLNs have been prepared by "solvent diffusion method" using lipids, such as glyceryl monostearate (GMS), tripalmitin (TP), Tween 80, and Stearyl amine as positive charge inducer. The prepared OLZ-SLNs were subjected to particle size analysis, zeta potential, and poly dispersity index measurement by using Malvern Zetasizer. Pharmacokinetics assessments of OLZ-SLNs were carried in conscious male Wistar rats through intravenous administration. Results have shown that average particle size and zeta potential of SLNs of GMS and TP were ranged from 165.1 ± 2.2 to 110.5 ± 0.5 and 35.29 ± 1.2 and 66.50 ± 0.7 mV, respectively. Relative bioavailability of OLZ in the brain was increased up to 23-fold and clearance was decreased when OLZ-SLNs while administrated intravenously. The area under the curve (AUC) and mean residence time (MRT) of OLZ-SLNs in brain were higher than OLZ suspension. These results indicate that SLNs are a promising drug delivery for OLZ. It may be an effective tool to enhance the bioavailability of OLZ in the brain with less dose administration, which could reduce the EPS associated with OLZ.

Quantification and evaluation of thymoquinone loaded mucoadhesive nanoemulsion for treatment of cerebral ischemia

Stroke is an important cause of deaths worldwide, resulting in an irreversible deterioration of the central nervous system. Finally, production of more free radicals. Therefore, Thymoquinone is having antioxidant property and reported to have a potential role in the amelioration of cerebral ischemia but due to low solubility and poor absorption; they exhibit low serum and tissue levels. Present work aims to prepare nanoemulsions in order enhance the bioavailability of drug and hence evaluate the drug targeting in brain via non-invasive nasal route administration. Thymoquinone Mucoadhesive Nanoemulsion (TMNE) was prepared by ionic gelation method; characterized for particles size, entrapment efficiency, zeta potential, and ex vivo permeation study. Optimized TMNE ended up with a mean globule size 94.8±6.61nm; zeta potential -13.5±1.01mV; drug content 99.86±0.35% and viscosity 110±12cp. Ultra Performance Liquid Chromatography-Photodiode Array (UPLC-PDA) based bioanalytical method was developed and validated for pharmacokinetics, biodistribution, brain-targeting efficiency (628.5786±44.79%) and brain drug-targeting potential (89.97±2.94%) studies via post intranasal administration which revealed enhanced bioavailability of TQ in brain as compared to intravenous administration. Improved neurobehavioural activity (locomotor and grip strength) was observed in middle cerebral artery occlusion induced cerebral ischemic rats after i.n. administration of TMNE.

Robust neuroprotective effects of intranasally delivered iNOS siRNA encapsulated in gelatin nanoparticles in the postischemic brain

The therapeutic efficacy of intranasal iNOS siRNA delivery was investigated in the postischemic rat brain after encapsulating on in gelatin nanoparticles (GNPs; diameter 188.0 ± 60.9 nm) cross-linked with 0.0667% glutaraldehyde (GA). Intranasally delivered GNPs were found in extracellular and intracellular compartments of many brain regions, including the olfactory bulb, cerebral cortex, and striatum at 1 hour after infusion and continued to be detected for days. Infarct volumes were markedly suppressed (maximal reduction to 42.1 ± 2.6%) at 2 days after 60 minutes of middle cerebral artery occlusion (MCAO) when iNOS siRNA/GNPs were delivered at 6 hours post-MCAO. In addition, this protective effect was manifested by reductions in neurological and behavioral deficits that were sustained for 2 weeks. Therapeutic potency of iNOS siRNA/GNPs was significantly greater and sustained longer than that of bare siRNA and prolonged and efficient iNOS by iNOS siRNA/GNP is responsible for the robust neuroprotective effect.

Oral nanomedicine approaches for the treatment of psychiatric illnesses

Psychiatric illnesses are a leading cause of disability and morbidity globally. However, the preferred orally dosed pharmacological treatment options available for depression, anxiety and schizophrenia are often limited by factors such as low drug aqueous solubility, food effects, high hepatic first-pass metabolism effects and short half-lives. Furthermore, the discovery and development of more effective psychotropic agents has stalled in recent times, with the majority of new drugs reaching the market offering similar efficacy, but suffering from the same oral delivery concerns. As such, the application of nanomedicine formulation approaches to currently available drugs is a viable option for optimizing oral drug delivery and maximizing treatment efficacy. This review focuses on the various delivery challenges encountered by psychotropic drugs, and the ability of nanomedicine formulation strategies to overcome these. Specifically, we critically review proof of concept in vitro and in vivo studies of nanoemulsions/microemulsions, solid lipid nanoparticles, dendrimers, polymeric micelles, nanoparticles of biodegradable polymers and nanosuspensions, and provide new insight into the various mechanisms for improved drug performance. The advantages and limitations of current oral nanomedicine approaches for psychotropic drugs are discussed, which will provide guidance for future research directions and assist in fostering the translation of such delivery systems to the clinical setting. Accordingly, emphasis has been placed on correlating the in vitro/in vivo performance of these nanomedicine approaches with their potential clinical outcomes and benefits for patients.

Nanoparticle transport across in vitro olfactory cell monolayers

Drug access to the CNS is hindered by the presence of the blood-brain barrier (BBB), and the intranasal route has risen as a non-invasive route to transport drugs directly from nose-to-brain avoiding the BBB. In addition, nanoparticles (NPs) have been described as efficient shuttles for direct nose-to-brain delivery of drugs. Nevertheless, there are few studies describing NP nose-to-brain transport. Thus, the aim of this work was (i) to develop, characterize and validate in vitro olfactory cell monolayers and (ii) to study the transport of polymeric- and lipid-based NPs across these monolayers in order to estimate NP access into the brain using cell penetrating peptide (CPPs) moieties: Tat and Penetratin (Pen). All tested poly(d,l-lactide-co-glycolide) (PLGA) and nanostructured lipid carrier (NLC) formulations were stable in transport buffer and biocompatible with the olfactory mucosa cells. Nevertheless, 0.7% of PLGA NPs was able to cross the olfactory cell monolayers, whereas 8% and 22% of NLC and chitosan-coated NLC (CS-NLC) were transported across them, respectively. Moreover, the incorporation of CPPs to NLC surface significantly increased their transport, reaching 46% of transported NPs. We conclude that CPP-CS-NLC represent a promising brain shuttle via nose-to-brain for drug delivery.

Fabrication and in vivo evaluation of Nelfinavir loaded PLGA nanoparticles for enhancing oral bioavailability and therapeutic effect

Nelfinavir mesylate (NFV) is an anti-viral drug, used in the treatment of Acquired Immunodeficiency Syndrome (AIDS). Poor oral bioavailability and shorter half-life (3.5-5 h) remain a major clinical limitation of NFV leading to unpredictable drug bioavailability and frequent dosing. In this context, the objective of the present study was to formulate NFV loaded poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), which can increase the solubility and oral bioavailability along with sustained release of the drug. NFV loaded PLGA-NPs were prepared by nanoprecipitation method using PLGA and Poloxomer 407. The prepared NPs were evaluated for particle size, zeta potential, morphology, drug content, entrapment efficiency (EE) and in vitro dissolution studies. Oral bioavailability studies were carried out in New Zealand rabbits by administering developed NFV PLGA-NPs and pure drug suspension. PLGA-NPs prepared by using 1:4 ratio of drug and PLGA, with a stirring rate of 1500 rpm for 4 h. The prepared NPs were in the size of 185 ± 0.83 nm with a zeta potential of 28.7 ± 0.09 mV. The developed NPs were found to be spherical with uniform size distribution. The drug content and EE of the optimized formulation were found to be 36 ± 0.19% and 72 ± 0.47% respectively. After oral administration of NFV PLGA-NPs, the relative bioavailability was enhanced about 4.94 fold compared to NFV suspension as a control. The results describe an effective strategy for oral delivery of NFV loaded PLGA NPs that helps in enhancing bioavailability and reduce the frequency of dosing.

Nose-To-Brain Delivery of PLGA-Diazepam Nanoparticles

The objective of the present investigation was to optimize diazepam (Dzp)-loaded poly(lactic-co-glycolic acid) nanoparticles (NP) to achieve delivery in the brain through intranasal administration. Dzp nanoparticles (DNP) were formulated by nanoprecipitation and optimized using Box-Behnken design. The influence of various independent process variables (polymer, surfactant, aqueous to organic (w/o) phase ratio, and drug) on resulting properties of DNP (z-average and drug entrapment) was investigated. Developed DNP showed z-average 148-337 d.nm, polydispersity index 0.04-0.45, drug entrapment 69-92%, and zeta potential in the range of -15 to -29.24 mV. Optimized DNP were further analyzed by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), ex-vivo drug release, and in-vitro cytotoxicity. Ex-vivo drug release study via sheep nasal mucosa from DNP showed a controlled release of 64.4% for 24 h. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay performed on Vero cell line showed less toxicity for DNP as compared to Dzp suspension (DS). Gamma scintigraphy and biodistribution study of DNP and DS was performed on Sprague-Dawley rats using technetium-99m-labeled ((99m)Tc) Dzp formulations to investigate the nose-to-brain drug delivery pathway. Brain/blood uptake ratios, drug targeting efficiency, and direct nose-to-brain transport were found to be 1.23-1.45, 258, and 61% for (99m)Tc-DNP (i.n) compared to (99m)Tc-DS (i.n) (0.38-1.06, 125, and 1%). Scintigraphy images showed uptake of Dzp from nose-to-brain, and this observation was in agreement with the biodistribution results. These results suggest that the developed poly(D,L-lactide-co-glycolide) (PLGA) NP could serve as a potential carrier of Dzp for nose-to-brain delivery in outpatient management of status epilepticus.

Formulation Strategy for the Delivery of Cyclosporine A: Comparison of Two Polymeric Nanospheres

A wide range of nanoparticles has been explored for the delivery of highly hydrophobic drugs, but very few publications provide comparative data of the performance of different nanoparticles. To address this need, this publication compares poly(lactic-co-glycolic acid) (PLGA) nanoparticles and nanospheres made from tyrosine-derived tri-block copolymers (termed TyroSpheres) for their respective performance as carriers for cyclosporine A (CSA). Using previously reported data on PLGA, we followed similar experimental protocols to evaluate the in vitro characteristics of TyroSpheres. Although there are some similarities between the two particle systems for the delivery of CSA, such as effective encapsulation and epidermal skin penetration, several differences were notable. First, the methods of preparation were different, i.e., self-assembly and emulsion-diffusion-evaporation process for TyroSpheres and PLGA, respectively. Second, TyroSpheres provided 7-day diffusion-controlled release, whereas PLGA nanoparticles provided >21-day erosion-controlled release. Third, the size of TyroSpheres was measured to be ~60–70 nm irrespective of drug loading, whereas the size of PLGA nanoparticles (~100–250 nm) was dependent on drug loading and the method of preparation. Overall, this publication provides a direct comparison between two different types of nanoparticles and illuminates the respective advantages and disadvantages, using CSA as a model for the release of highly hydrophobic drugs.

Brain delivery of buspirone hydrochloride chitosan nanoparticles for the treatment of general anxiety disorder

The present work discusses the preparation, characterization and in vivo evaluation of thiolated chitosan nanoparticles (TCS-NPs) of buspirone hydrochloride (BUH) for brain delivery through intranasal route. TCS NPs were prepared by ionic gelation method and characterized for various parameters. The NPs formed were having particle size of 226.7±2.52nm with PDI 0.483±0.031. Drug entrapment efficiency (EE) and loading capacity (LC) were found to be 81.13±2.8 and 49.67±5.5%. The cumulative percentage drug permeation through nasal mucosa was 76.21%. Bioadhesion study carried out on porcine mucin and showed a bioadhesion efficiency of 90.218±0.134%. Nose-to-brain delivery of placebo NPs was investigated by confocal laser scanning microscopy (CLSM) technique using rhodamine-123 as a marker. The brain concentration achieved after intranasal administration of TCS-NPs was 797.46±35.76ng/ml with tmax 120min which was significantly higher than achieved after intravenous administration on BUH solution 384.15±13.42ng/ml and tmax of 120min and intranasal administration of BUH solution 417.77±19.24ng/ml and tmax 60min.

Myelin repair in vivo is increased by targeting oligodendrocyte precursor cells with nanoparticles encapsulating leukaemia inhibitory factor (LIF)

Multiple sclerosis (MS) is a progressive demyelinating disease of the central nervous system (CNS). Many nerve axons are insulated by a myelin sheath and their demyelination not only prevents saltatory electrical signal conduction along the axons but also removes their metabolic support leading to irreversible neurodegeneration, which currently is untreatable. There is much interest in potential therapeutics that promote remyelination and here we explore use of leukaemia inhibitory factor (LIF), a cytokine known to play a key regulatory role in self-tolerant immunity and recently identified as a pro-myelination factor. In this study, we tested a nanoparticle-based strategy for targeted delivery of LIF to oligodendrocyte precursor cells (OPC) to promote their differentiation into mature oligodendrocytes able to repair myelin. Poly(lactic-co-glycolic acid)-based nanoparticles of ∼120 nm diameter were constructed with LIF as cargo (LIF-NP) with surface antibodies against NG-2 chondroitin sulfate proteoglycan, expressed on OPC. In vitro, NG2-targeted LIF-NP bound to OPCs, activated pSTAT-3 signalling and induced OPC differentiation into mature oligodendrocytes. In vivo, using a model of focal CNS demyelination, we show that NG2-targeted LIF-NP increased myelin repair, both at the level of increased number of myelinated axons, and increased thickness of myelin per axon. Potency was high: a single NP dose delivering picomolar quantities of LIF is sufficient to increase remyelination. Impact statement Nanotherapy-based delivery of leukaemia inhibitory factor (LIF) directly to OPCs proved to be highly potent in promoting myelin repair in vivo: this delivery strategy introduces a novel approach to delivering drugs or biologics targeted to myelin repair in diseases such as MS.

Nanoneurotherapeutics approach intended for direct nose to brain delivery

CONTEXT

Brain disorders remain the world's leading cause of disability, and account for more hospitalizations and prolonged care than almost all other diseases combined. The majority of drugs, proteins and peptides do not readily permeate into brain due to the presence of the blood-brain barrier (BBB), thus impeding treatment of these conditions.

OBJECTIVE

Attention has turned to developing novel and effective delivery systems to provide good bioavailability in the brain.

METHODS

Intranasal administration is a non-invasive method of drug delivery that may bypass the BBB, allowing therapeutic substances direct access to the brain. However, intranasal administration produces quite low drug concentrations in the brain due limited nasal mucosal permeability and the harsh nasal cavity environment. Pre-clinical studies using encapsulation of drugs in nanoparticulate systems improved the nose to brain targeting and bioavailability in brain. However, the toxic effects of nanoparticles on brain function are unknown.

RESULT AND CONCLUSION

This review highlights the understanding of several brain diseases and the important pathophysiological mechanisms involved. The review discusses the role of nanotherapeutics in treating brain disorders via nose to brain delivery, the mechanisms of drug absorption across nasal mucosa to the brain, strategies to overcome the blood brain barrier, nanoformulation strategies for enhanced brain targeting via nasal route and neurotoxicity issues of nanoparticles.

Ufasomes nano-vesicles-based lyophilized platforms for intranasal delivery of cinnarizine: preparation, optimization, ex-vivo histopathological safety assessment and mucosal confocal imaging

To circumvent the low and erratic absorption of orally administrated cinnarizine (CN), intranasal lyophilized gels containing unsaturated fatty acid liposomes (ufasomes) and encapsulating CN were prepared from oleic acid using a simple assembling strategy. The effects of varying drug concentration and cholesterol percentage on ufasomes size, polydispersity index and entrapment efficiency were investigated using 3(1)4(1) full factorial design. The optimized ufasomes that contained 14% cholesterol relative to oleic acid displayed spherical morphology with average size of 788 nm and entrapment efficiency of 80.49%. To overcome the colloidal instability of CN-loaded ufasomes dispersions and their short residence time in the nasal cavity, the ufasomes were incorporated into mucoadhesive hydrogels that were lyophilized into unit dosage forms for accurate dosing. Scanning electron micrographs of the lyophilized gel revealed that the included ufasomes were intact, non-aggregating and maintained their spherical morphology. Rheological characterization of reconstituted ufasomal lyophilized gel ensured ease of application. Furthermore, the gel induced minor histopathological alterations in sheeps' nasal mucosa. Ex-vivo confocal laser imaging confirmed the ability of ufasomes to penetrate deep through nasal mucosa layers. The results highlighted in the current work confirm the feasibility of using CN-loaded ufasomal gels for intranasal drug delivery.

Paclitaxel and etoposide co-loaded polymeric nanoparticles for the effective combination therapy against human osteosarcoma

BACKGROUND

The combination of chemotherapeutic drugs with different pharmacological action has emerged as a promising therapeutic strategy in the treatment of cancers. Present study examines the antitumor potential of paclitaxel (PTX) and etoposide (ETP)-loaded PLGA nanoparticles for the treatment of osteosarcoma.

RESULTS

The resulting drug-loaded PLGA NP exhibited a nanosize dimension with uniform spherical morphology. The NP exhibited a sustained release profile for both PTX and ETP throughout the study period without any sign of initial burst release. The combinational drug-loaded PLGA NP enhanced the cytotoxic effect in MG63 and Saos-2 osteosarcoma cell lines, in comparison to either native drug alone or in cocktail combinations. Additionally, NPs showed an appreciable uptake in MG63 cells in a time-based manner. Co-delivery of anticancer drugs resulted in enhanced cell cycle arrest and cell apoptosis. The results clearly showed that combinational drugs remarkably improved the therapeutic index of chemotherapeutic drugs. The greater inhibitory effect of nanoparticle combination would be of great advantage during systemic cancer therapy.

CONCLUSION

Taken together, our study demonstrated that PTX-ETP/PLGA NP based combination therapy holds significant potential towards the treatment of osteosarcoma.

Nanotechnology-mediated nose to brain drug delivery for Parkinson's disease: a mini review

Nose to brain delivery of neurotherapeutics have been tried by several researchers to explore the virtues of this route viz. circumvention of BBB, avoidance of hepatic metabolism, practicality, safety, ease of administration and non-invasiveness. Nanoparticle (NP) therapeutics is an emerging modality for the treatment of Parkinson's disease (PD) as it offers targeted delivery and enhances the therapeutic efficacy and/or bioavailability of neurotherapeutics. This review presents a concise incursion into the nanomedicines suitable for PD therapy delivered via naso-brain transport. Clinical signs of PD, its pathophysiology, specific genetic determinants, diagnosis and therapy involved have been hashed out. Properties of brain-targeting NPs, transport efficacy and various nanocarriers developed so far also been furnished. In our opinion, nanotechnology-enabled naso-brain drug delivery is an excellent means of delivering neurotherapeutics and is a promising avenue for researchers to develop new formulations for the effective management of PD.

Biodegradable intranasal nanoparticulate drug delivery system of risedronate sodium for osteoporosis

CONTEXT

Osteoporosis (OP) is the most common metabolic bone disease predominantly found in elderly people. It is associated with reduced bone mineral density, results in a higher probability of fractures, especially of the hip, vertebrae, and distal radius. Worldwide prevalence of OP is considered a serious public health concern.

OBJECTIVE

The purpose of the present work was to develop and evaluate polymeric nanoparticles (NPs) of risedronate sodium (RIS) for the treatment of OP using intranasal (IN) route in order to reduce peripheral toxic effects.

MATERIALS AND METHODS

Polymeric NPs of RIS were prepared by nanoprecipitation methods. Formulations were developed and evaluated in context to in vitro drug release, ex vivo permeation, in vivo study, and biochemical studies.

RESULTS AND DISCUSSIONS

The particles size, entrapment efficiency (EE) (%), and loading capacity (LC) (%) of optimized formulations were found to be 127.84 ± 6.33 nm, 52.65 ± 5.21, and 10.57 ± 1.48, respectively. Release kinetics showed diffusion-controlled, Fickian release pattern. Ex vivo permeation study showed RIS from PLGA-NPs permeated significantly (p < 0.05) through nasal mucosa. In vivo study showed a marked difference in micro-structure (trabeculae) in bone internal environment. Biochemical estimation of treated group and RIS PLGA indicated a significant recovery (p < 0.01) as compared with the toxic group.

CONCLUSION

Polymeric NPs of RIS were prepared successfully using biodegradable polymer (PLGA). Intranasal delivery showed a good result in in vivo study. Thus PLGA-NPs have great potential for delivering the RIS for the treatment and prevention of OP after clinical evaluation in near future.

Biodegradable PLGA nanoparticles loaded with hydrophobic drugs: confocal Raman microspectroscopic characterization

PLGA nanoparticles with bicyclol and Br-NBP were for the first time successfully characterized by a laser trapping/confocal Raman spectroscopic technique only using individual nanoparticles.

Increasing the Efficiency of Parkinson's Disease Treatment Using a poly(lactic-co-glycolic acid) (PLGA) Based L-DOPA Delivery System

To compare the efficacy of L-DOPA administered intranasally in the form of nanoparticles (nano-DOPA) and in standard drug forms using a rat Parkinson's Disease (PD) model. L-DOPA-containing nanoparticles (250±50 nm) were synthesized using the double emulsion method. The efficacy of nano-DOPA therapy was studied in Wistar rats with 6-OHDA-induced PD. Drugs were administered daily, 0.35 mg/kg (by L-DOPA). Animals' motor coordination and behavior were analyzed using the forelimb placing task and several other tests. Thirty minutes after the first administration, animals treated with L-DOPA, L-DOPA+benserazide, and nano-DOPA showed equally significant (p<0.05) improvements in coordination performance in comparison to the non-treated group. After 4 weeks of treatment, coordination performance in the nano-DOPA group (89±13% of the intact control level) was twice as high as in the L-DOPA and L-DOPA+benserazide groups, which did not differ from non-treated animals. The effect of nano-DOPA was significantly higher and more long-lasting (90±13% at 24 h after administration); moreover, it was still significant one week after the treatment was discontinued. Intranasal nano-DOPA was found to provide a lasting motor function recovery in the 6-OHDA-induced rat PD model with the effect sustained for one week after discontinuation, while the same doses of standard drugs provided significant effect only after the first administration. L-DOPA administered in the form of PLGA-based nanoparticles had a higher effective half-life, bioavailability, and efficacy; it was also efficiently delivered to the brain by intranasal administration.

Green synthesis of pullulan stabilized gold nanoparticles for cancer targeted drug delivery

The aim of this study was to synthesize green chemistry based gold nanoparticles using liver specific biopolymer and to develop a liver cancer targeted drug delivery system with enhanced efficacy and minimal side effects. Pullulan stabilized gold nanoparticles (PAuNPs) were coupled with 5-Fluorouracil (5-Fu) and folic acid (Fa) which could be used as a tool for targeted drug delivery and imaging of cancer. The toxicity of 5-Fu, 5-Fu adsorbed gold nanoparticles (5-Fu@AuNPs), Fa-coupled 5-Fu adsorbed gold nanoparticles (5-Fu@AuNPs-Fa), was studied using zebrafish embryo as an in vivo model. The in vitro cytotoxicity of free 5-Fu, 5-Fu@AuNPs, 5-Fu@AuNPs-Fa against HepG2 cells was studied and found that the amount of 5-Fu required to achieve 50% of growth of inhibition (Ic50) was much lower in 5-Fu@AuNP-Fa than in free 5-Fu, 5-Fu@AuNPs. The in vivo biodistribution of PAuNPs showed that higher amount of gold had been accumulated in liver (54.42±5.96 μg) than in other organs.

Formulation and optimization of polymeric nanoparticles for intranasal delivery of lorazepam using Box-Behnken design: in vitro and in vivo evaluation

The aim of the present study was to optimize lorazepam loaded PLGA nanoparticles (Lzp-PLGA-NPs) by investigating the effect of process variables on the response using Box-Behnken design. Effect of four independent factors, that is, polymer, surfactant, drug, and aqueous/organic ratio, was studied on two dependent responses, that is, z-average and % drug entrapment. Lzp-PLGA-NPs were successfully developed by nanoprecipitation method using PLGA as polymer, poloxamer as surfactant and acetone as organic phase. NPs were characterized for particle size, zeta potential, % drug entrapment, drug release behavior, TEM, and cell viability. Lzp-PLGA-NPs were characterized for drug polymer interaction using FTIR. The developed NPs showed nearly spherical shape with z-average 167–318 d·nm, PDI below 0.441, and −18.4 mV zeta potential with maximum % drug entrapment of 90.1%. In vitro drug release behavior followed Korsmeyer-Peppas model and showed initial burst release of 21.7 ± 1.3% with prolonged drug release of 69.5 ± 0.8% from optimized NPs up to 24 h. In vitro drug release data was found in agreement with ex vivo permeation data through sheep nasal mucosa. In vitro cell viability study on Vero cell line confirmed the safety of optimized NPs. Optimized Lzp-PLGA-NPs were radiolabelled with Technitium-99m for scintigraphy imaging and biodistribution studies in Sprague-Dawley rats to establish nose-to-brain pathway.

Distribution of α-asarone in brain following three different routes of administration in rats

The goal of the present paper is to compare the distributions of α-asarone administered to rats through three different routes: oral, intravenous and intranasal. The concentrations of α-asarone in seven distinct brain regions, the olfactory bulb, cerebellum, hypothalamus, frontal cortex, striatum, hippocampus and medulla/pons as well as in plasma and cerebrospinal fluid (CSF), were determined by HPLC. The quantities of α-asarone accumulated in liver were measured to determine whether α-asarone could generate hepatotoxicity when administered via the three different routes. The results indicated that α-asarone could be absorbed via two different routes into the brain, after intranasal administration of dry powders. In the systemic route, α-asarone immediately entered the brain through the blood-brain barrier (BBB) after uptake into the circulatory system. In the olfactory bulb route, α-asarone traveled from the olfactory epithelium in the nasal cavity straight into brain tissue via the olfactory bulb. Furthermore, intranasal administration of α-asarone as a dry powder can ensure quick absorption and avoid excessive concentrations in the blood and liver, while achieving concentrations in the brain comparable to those attained by intravenous and oral administration routes.

Surface engineered nanostructured lipid carriers for efficient nose to brain delivery of ondansetron HCl using Delonix regia gum as a natural mucoadhesive polymer

The objective of this investigation was to fabricate ondansetron hydrochloride [OND] loaded mucoadhesive nanostructured lipid carriers [NLCs] for efficient delivery to brain through nasal route. Mucoadhesive NLCs thereby sustaining drug release for longer time in nasal cavity. NLCs were prepared by high pressure homogenization [HPH] technique using glycerol monostearate [GMS]; as solid lipid, Capryol 90; as liquid lipid, soya lecithin; as surfactant and poloxamer 188; as cosurfactant. In the fabrication of NLCs, Delonix regia gum [DRG], isolated from seeds of D. regia belonging to family fabiaceae was used as a mucoadhesive polymer. The NLCs were evaluated for particle size, morphology, drug-entrapment efficiency [%EE], mucoadhesive strength, in vitro drug release, histological examination, ex vivo permeation study, in vivo biodistribution and pharmacokinetic studies in the brain/blood following intravenous [i.v.] and intranasal [i.n.] administration. Particle size, PDI, Zeta potential was observed in the range of 92.28-135nm, 0.32-0.46, and -11.5 to -36.2 respectively. Prepared NLCs achieved thermodynamic stability, control release pattern with minor histopathological changes in sheep nasal mucosa. The significantly [P<0.05] higher values for selected batch was observed, when administered by i.n. route showed higher drug targeting efficiency [506%] and direct transport percentage [97.14%] which confirms the development of promising OND-loaded NLC for efficient nose-to-brain delivery.

Multidrug resistance in cancer or inefficacy of neuroactive agents: innovative strategies to inhibit or circumvent the active efflux transporters selectively

Multidrug resistance (MDR) is a crucial issue in the treatment of cancer cells that protect themselves by overexpression of active efflux transporters (AETs). AET expression maintains the homeostasis in healthy tissues and in the blood-brain barrier it often prevents drugs from reaching the brain. Inhibition of AETs could therefore be a valuable solution for preventing MDR; but nonselective long-term AET blocking can be harmful toward healthy tissues and, in particular, the brain. This review looks at the development of innovative formulations suitable for selectively blocking or avoiding AETs as promising ways to overcome the challenges of MDR and inefficacy of neuroactive agents.

Nasal-nanotechnology: revolution for efficient therapeutics delivery

CONTEXT

In recent years, nanotechnology-based delivery systems have gained interest to overcome the problems of restricted absorption of therapeutic agents from the nasal cavity, depending upon the physicochemical properties of the drug and physiological properties of the human nose.

OBJECTIVE

The well-tolerated and non-invasive nasal drug delivery when combined with the nanotechnology-based novel formulations and carriers, opens the way for the effective systemic and brain targeting delivery of various therapeutic agents. To accomplish competent drug delivery, it is imperative to recognize the interactions among the nanomaterials and the nasal biological environment, targeting cell-surface receptors, drug release, multiple drug administration, stability of therapeutic agents and molecular mechanisms of cell signaling involved in patho-biology of the disease under consideration.

METHODS

Quite a few systems have been successfully formulated using nanomaterials for intranasal (IN) delivery. Carbon nanotubes (CNTs), chitosan, polylactic-co-glycolic acid (PLGA) and PLGA-based nanosystems have also been studied in vitro and in vivo for the delivery of several therapeutic agents which shown promising concentrations in the brain after nasal administration.

RESULTS AND CONCLUSION

The use of nanomaterials including peptide-based nanotubes and nanogels (NGs) for vaccine delivery via nasal route is a new approach to control the disease progression. In this review, the recent developments in nanotechnology utilized for nasal drug delivery have been discussed.

Preparation of surface multiple-coated polylactide acid drug-loaded nanoparticles for intranasal delivery and evaluation on its brain-targeting efficiency

PURPOSE

To prepare a mixture of multiple-coated aniracetam nasal polylactic-acid nanoparticles (M-C-PLA-NP) and evaluate its stability preliminarily in vitro and its brain-targeting efficiency in vivo.

METHODS

The solvent diffusion-evaporation combined with magnetic stirring method has been chosen for the entrapment of aniracetam. The M-C-PLA-NP was characterized with respect to its morphology, particle size, size distribution and aniracetam entrapment efficiency. The in vivo distribution was studied in male SD rats after an intranasal administration.

RESULTS

In vitro release of M-C-PLA-NP showed two components with an initial rapid release due to the surface-associated drug and followed by a slower exponential release of aniracetam, which was dissolved in the core. The AUC0 → 30 min of M-C-PLA-NP in brain tissues resulted in a 5.19-fold increase compared with aniracetam solution. The ratios of AUC in brain to that in other tissues obtained after nasal application of M-C-PLA-NP were significantly higher than those of aniracetam solution.

CONCLUSION

Therefore, it can be concluded that M-C-PLA-NP demonstrated its potential on increasing the brain-targeting efficiency of drugs and will be used as novel brain-targeting agent for nasal drug delivery.

Enhanced bioavailability and intestinal uptake of Gemcitabine HCl loaded PLGA nanoparticles after oral delivery

The aim of study was to formulate PLGA nanoparticles (NPs) of Gemcitabine HCl for enhanced oral bioavailability via absorption through M cells of Peyer's patches. Commercially, the drug is available as i.v. infusion due to its short half life (8-17 min), rapid metabolism and limited tumor uptake. The NPs were prepared by multiple solvent emulsification method. Optimized formulation had particle size of 166.4±2.42 nm, and entrapment of 56.48±3.63%. TEM image revealed discrete spherical structures of NPs. DSC and FTIR studies confirmed absence of interaction between drug and polymer. In vitro and ex vivo studies demonstrated sustained release from the NPs. The enhanced absorption and uptake of NPs in Caco-2 cells and in vivo absorption in intestinal tissue after oral delivery in rats was confirmed by confocal microscopy. Transport studies in Caco-2 cells confirmed 6.37-fold permeability for NPs. In vitro antiproliferative studies confirmed marked cytotoxicity of NPs on K562 leukemia cell lines. In vivo pharmacokinetic studies in rats showed 21.47-folds bioavailability enhancement from NPs. Hence, orally delivered Gemcitabine HCl loaded NPs have the potential for improving its bioavailability and avoiding side effects associated with iv infusions as well as enhancing patient compliance through "Chemotherapy at Home".

Optimization of artemether-loaded NLC for intranasal delivery using central composite design

The objective of the study was to optimize artemether-loaded nanostructured lipid carriers (ARM-NLC) for intranasal delivery using central composite design. ARM-NLC was prepared by microemulsion method with optimized formulation having particle size of 123.4 nm and zeta potential of -34.4 mV. Differential scanning calorimetry and powder X-ray diffraction studies confirmed that drug existed in amorphous form in NLC formulation. In vitro cytotoxicity assay using SVG p12 cell line and nasal histopathological studies on sheep nasal mucosa indicated the developed formulations were non-toxic and safe for intranasal administration. In vitro release studies revealed that NLC showed sustained release up to 96 h. Ex vivo diffusion studies using sheep nasal mucosa revealed that ARM-NLC had significantly lower flux compared to drug solution (ARM-SOL). Pharmacokinetic and brain uptake studies in Wistar rats showed significantly higher drug concentration in brain in animals treated intranasally (i.n.) with ARM-NLC. Brain to blood ratios for ARM-NLC (i.n.), ARM-SOL (i.n.) and ARM-SOL (i.v.) were 2.619, 1.642 and 0.260, respectively, at 0.5 h indicating direct nose to brain transport of ARM. ARM-NLC showed highest drug targeting efficiency and drug transport percentage of 278.16 and 64.02, respectively, which indicates NLC had better brain targeting efficiency compared to drug solution.

Improvement in antihypertensive and antianginal effects of felodipine by enhanced absorption from PLGA nanoparticles optimized by factorial design

Objective of the present investigation was to enhance the bioavailability of felodipine by targeting the M cells of Peyer's patches using PLGA nanoparticles (NPs). Felodipine exhibits poor bioavailability due to limited aqueous solubility and extensive first pass metabolism. NPs were prepared using nanoprecipitation and optimized by 3(2) factorial design. Particle size (PS) and entrapment efficiency (% EE) were dependent on Drug/PLGA ratio (X1) and Pluronic F-68 (X2) concentration. % EE, PS and Zeta potential for optimized batch were 91.56±3.21%, 161.3±2.23 nm and -25.7±2.52 mV respectively. DSC, XRD and FTIR studies confirmed compatibility of PLGA and drug. TEM image confirmed the spherical shape. The in vitro and ex vivo studies using rat stomach and intestinal segment confirmed sustained release from NPs. Pharmacodynamic studies in rats showed control of blood pressure and ECG changes for extended duration. Hence, NPs can be a suitable alternative to the current available therapy in hypertension and angina by enhancing the bioavailability.

Optimization of curcumin nanoemulsion for intranasal delivery using design of experiment and its toxicity assessment

The objective of the study was to optimize curcumin nanoemulsion for intranasal delivery using design of experiment. Box-Behnken design was constructed using oil, surfactant and co-surfactant concentration as independent variables and their affect on response y1 (globule size) and y2 (zeta potential) were studied. The ANOVA test identified the significant factors that affected the responses. For globule size, percentage of oil, surfactant and co-surfactant were identified as significant model terms whereas for zeta potential, oil and co-surfactant were found to be significant. Critical factors affecting the responses were identified using perturbation and contour plots. The derived polynomial equation and contour graph aid in predicting the values of selected independent variables for preparation of optimum nanoemulsion with desired properties. Further, 2(4) factorial design was used to study influence of chitosan on particle size and zeta potential. The formulations were subjected to in vitro cytotoxicity using SK-N-SH cell line and nasal ciliotoxicity studies. The developed formulations did not show any toxicity and were safe for intranasal delivery for brain targeting. In vitro diffusion studies revealed that nanoemulsions had a significantly higher release compared to drug solution. Ex vivo diffusion studies were carried out using sheep nasal mucosa fixed onto Franz diffusion cells. Mucoadhesive nanoemulsion showed higher flux and permeation across sheep nasal mucosa.

Formulations for Intranasal Delivery of Pharmacological Agents to Combat Brain Disease: A New Opportunity to Tackle GBM?

Despite recent advances in tumor imaging and chemoradiotherapy, the median overall survival of patients diagnosed with glioblastoma multiforme does not exceed 15 months. Infiltration of glioma cells into the brain parenchyma, and the blood-brain barrier are important hurdles to further increase the efficacy of classic therapeutic tools. Local administration methods of therapeutic agents, such as convection enhanced delivery and intracerebral injections, are often associated with adverse events. The intranasal pathway has been proposed as a non-invasive alternative route to deliver therapeutics to the brain. This route will bypass the blood-brain barrier and limit systemic side effects. Upon presentation at the nasal cavity, pharmacological agents reach the brain via the olfactory and trigeminal nerves. Recently, formulations have been developed to further enhance this nose-to-brain transport, mainly with the use of nanoparticles. In this review, the focus will be on formulations of pharmacological agents, which increase the nasal permeation of hydrophilic agents to the brain, improve delivery at a constant and slow release rate, protect therapeutics from degradation along the pathway, increase mucoadhesion, and facilitate overall nasal transport. A mounting body of evidence is accumulating that the underexplored intranasal delivery route might represent a major breakthrough to combat glioblastoma.

Application of multiple regression analysis in optimization of anastrozole-loaded PLGA nanoparticles

The present investigation deals with development of anastrozole-loaded PLGA nanoparticles (NPs) as an alternate to conventional cancer therapy. The NPs were prepared by nanoprecipitation method and optimized using multiple regression analysis. Independent variables included drug:polymer ratio (X1), polymer concentration in organic phase (X2) and surfactant concentration in aqueous phase (X3) while dependent variables were percentage drug entrapment (PDE) and particle size (PS). Results of desirability criteria, check point analysis and normalized error were considered for selecting the formulation with highest PDE and lowest PS. Prepared NPs were characterized for zeta potential, transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and in vitro drug release studies. DSC and TEM studies indicated absence of any drug-polymer interaction and spherical nature of NPs, respectively. In vitro drug release showed biphasic pattern exhibiting Fickian diffusion-based release mechanism. This delivery system of anastrozole is expected to reduce the side effects associated with the conventional cancer therapy by reducing dosing frequency.

Evaluation of neuropeptide loaded trimethyl chitosan nanoparticles for nose to brain delivery

Leucine-enkephalin (Leu-Enk) is a neurotransmitter or neuromodulator in pain transmission. Due to non-addictive opioid analgesic activity of this peptide, it might have great potential in pain management. Leu-Enk loaded N-trimethyl chitosan (TMC) nanoparticles were prepared and evaluated as a brain delivery vehicle via nasal route. TMC biopolymer was synthesized and analyzed by (1)H NMR spectroscopy. TMC nanoparticles were prepared by ionic gelation method. Mean peptide encapsulation efficiency and loading capacity were 78.28±3.8% and 14±1.3%, respectively. Mean particle size, polydispersity index and zeta potential were found to be 443±23 nm, 0.317±0.17 and +15±2 mV respectively for optimized formulations. Apparent permeability coefficient (Papp) of Leu-Enk released from nanoparticles across the porcine nasal mucosa was determined to be 7.45±0.30×10(-6) cm s(-1). Permeability of Leu-Enk released from nanoparticles was 35 fold improved from the nasal mucosa as compared to Leu-Enk solution. Fluorescent microscopy of brain sections of mice showed higher accumulation of fluorescent marker NBD-F labelled Leu-Enk, when administered nasally by TMC nanoparticles, while low brain uptake of marker solution was observed. Furthermore, enhancement in brain uptake resulted into significant improvement in the observed antinociceptive effect of Leu-Enk as evidenced by hot plate and acetic acid induced writhing assay.

Fabrication and statistical optimization of surface engineered PLGA nanoparticles for naso-brain delivery of ropinirole hydrochloride: in-vitro-ex-vivo studies

Ropinirole hydrochloride (RPN), a nonergot dopamine D2-agonist used in the management of Parkinson's disease, has poor oral bioavailability (52%) due to extensive hepatic metabolism. The intent of present research work was aimed at design and statistical optimization of RPN-loaded poly (lactic-co-glycolic acid) (PLGA)-based biodegradable nanoparticles (NPs) surface modified using natural emulsifier, vitamin E (d-α-tocopheryl polyethylene glycol 1000 succinate [TPGS]) for direct nose-to-brain delivery in order to avoid hepatic first-pass metabolism, and improve therapeutic efficacy with sustained drug release. RPN-NPs were prepared by modified nanoprecipitation technique and optimized using 2(3) factorial design of experiment. The effect of polymer and emulsifier concentration was evaluated on particle size and entrapment efficiency (EE%). Formulation PL6 was considered as desirable with highest EE% (72.3 ± 6.1%), PS (279.4 ± 1.8 nm), zeta potential (-29.4 ± 2.6 mV), and cumulative drug diffusion of 96.43 ± 3.1% in 24 h. The ANOVA results for the dependent variables demonstrated that the model was significant (p value < 0.05) for response variables. Histopathological study of optimized batch (PL6) demonstrated good retention of NPs with no severe signs of damage on the integrity of nasal mucosa. Differential scanning calorimetry revealed the absence of any chemical interaction between RPN, PLGA, and TPGS while SEM study confirmed spherical shape of optimized NPs. Accelerated stability studies of freeze-dried optimized batch demonstrated negligible change in the average PS and EE% after storage at 25 ± 2 °C/60 ± 5% (relative humidity (RH) for the period of three months. The promising results of optimized batch suggested practicability of investigated system for enhancement of bioavailability and brain targeting of CNS acting drugs like RPN.