Improved pharmacokinetics and antihyperlipidemic efficacy of rosuvastatin-loaded nanostructured lipid carriers

In the present study, rosuvastatin calcium-loaded nanostructured lipid carriers were developed and optimized for improved efficacy. The ROS-Ca-loaded NLC was prepared using melt emulsification ultrasonication technique and optimized by Box–Behnken statistical design. The optimized NLC composed of glyceryl monostearate (solid lipid) and capmul MCM EP (liquid lipid) as lipid phase (3% w/v), poloxamer 188 (1%) and tween 80 (1%) as surfactant. The mean particle size, polydispersity index (PDI), zeta potential (ζ) and entrapment efficiency (%) of optimized NLC formulation was observed to be 150.3?±?4.67?nm, 0.175?±?0.022, ?32.9?±?1.36?mV and 84.95?±?5.63%, respectively. NLC formulation showed better in vitro release in simulated intestinal fluid (pH 6.8) than API suspension. Confocal laser scanning showed deeper permeation of formulation across rat intestine compared to rhodamine B dye solution. Pharmacokinetic study on female albino Wistar rats showed 5.4-fold increase in relative bioavailability with NLC compared to API suspension. Optimized NLC formulation also showed significant (p?<?0.01) lipid lowering effect in hyperlipidemic rats. Therefore, NLC represents a great potential for improved efficacy of ROS-Ca after oral administration.     

新型纳米粒给药系统——纳米结构的脂质载体

固体脂质纳米粒（SLN）已被公认是一种新型的纳米粒给药系统，但SLN有不同程度的潜在问题。作为新一代的纳米粒给药系统——纳米结构的脂质载体（Nanostructured lipid carriers，NLC）可减小或者避免SLN有限载药能力及储藏过程包封药物泄漏的问题，而且能调整SLN的释放曲线。NLC以固体脂质与物态上相异的液体脂质混合制备得到，形成3种类型特殊结构的脂质骨架：结晶不完全态、无定形态、复合态。现介绍一种特殊的制备方法，不仅适合于制备NLC，而且也可作为制备高粒子浓度（30％～95％）SLN分散液的方法。描述了NLC作为给药系统潜在的应用前景。     

Nanostructured lipid carriers as novel drug delivery system for lung cancer gene therapy

Context: Nanostructured lipid carriers (NLC) are potentially good colloidal drug carriers for gene delivery. They are advised to be the second lifetime of lipid nanocarriers.

Objective: The aim of this study is to develop novel modified NLC as nanomedicine for delivery of plasmid-containing enhanced green fluorescence protein (pEGFP). This system could target the lung cancer cells through receptor-mediated pathways to increase the nuclear uptake of genetic materials.

Methods: In the present study, pEGFP-loaded NLC (NLC/pEGFP) were prepared. Transferrin (Tf) containing ligands were used for the surface coating of the vectors. In vitro transfection efficiency of the modified vectors was evaluated in human alveolar adenocarcinoma cell line (A549 cells) and in vivo transfection efficiency of the modified vectors was evaluated on mice bearing A549 cells model.

Results: Tf-modified NLC/pEGFP (Tf-NLC/pEGFP) has a particle size of 157?nm, and ～82% of gene loading quantity. Tf-NLC/pEGFP displayed remarkably higher transfection efficiency than non-modified NLC/pEGFP both in vitro and in vivo.

Conclusion: The results demonstrate that the novel NLC gene delivery system offers an effective strategy for lung cancer gene therapy.     

Intracellular delivery of 10-hydroxycamptothecin with targeted nanostructured lipid carriers against multidrug resistance

10-Hydroxycamptothecin (HCPT) is a clinical therapy agent against hepatoma. The chemotherapy of HCPT is strongly obstructed by the emergence of multidrug resistance (MDR), serious systemic toxicity, malfunction of rapid phagocytic and renal clearance disorder which are undesirable for its chemotherapy. In this paper, a drug delivery system (DDS) for HCPT has been developed in order to overcome MDR. Nanostructured lipid carriers (NLC) coated with xyloglucan (XG) was prepared by soya oil and XG consisting of side chains with galactose residues, a terminal moiety that can be used to target HCPT to hepatoma. The therapeutic potential of XG-NLC/HCPT was investigated on HepG2/HCPT cells and on human tumor xenograft nude mouse model (implanted with HepG2/HCPT cells). XG-NLC/HCPT not only indicated superior cytotoxicity against the drug resistant HepG2 cells but also in vivo, generated a higher therapeutic effect. Systemic toxicity study demonstrated that the carrier reduced systemic toxicity. XG-NLC/HCPT proved a great potential to serve as DDS to overcome MDR of HepG2/HCPT cells. These results suggested that XG NLC/HCPT represent a promising carrier for drug delivery to the hepatoma and reverse the drug resistant of HepG2 cells and XG could be exploited as a potential targeting device for liver tissue.     

Quality by design approach to understand the process of optimization of iloperidone nanostructured lipid carriers for oral bioavailability enhancement

Abstract

Context: The current work was carried out by exploring the principles of quality by design approach to develop an optimized nanostructured lipid carrier (NLC) formulation of poorly water soluble active iloperidone (ILO) through systematic statistical study. The potential of NLC for improving the oral bioavailability of ILO was also evaluated.

Objective: To understand the effect of formulation variables (critical parameters) on the performance characteristics (critical quality attributes) of NLC.

Materials and methods: A 3-factor, 3-level Box–Behnken factorial design was explored to predict the responses such as particle size (Y₁) and % entrapment efficiency (EE) (Y₂) when concentration of lipid (X₁), concentration of drug (X₂) and concentration of surfactant (X₃) were selected as independent variables.

Results and discussion: Particle size analysis revealed that all the batches were within the nanometer range. The % EE was found to be between 63% and 96%. In-vitro release study demonstrated sustained release profile of ILO NLC. The pharmacokinetic study in Wistar rats over the period of 24?h demonstrated 8.30-fold increase in oral bioavailability of ILO NLC as compared with ILO pure drug suspension.

Conclusion: The NLC formulation remarkably improved the oral bioavailability of ILO and demonstrated a promising perspective for oral delivery of poorly water-soluble drugs.     

Liver-targeted delivery of asiatic acid nanostructured lipid carrier for the treatment of liver fibrosis

Liver fibrosis is a major global health concern. Management of chronic liver disease is severely restricted in clinics due to ineffective treatment approaches. However, a lack of targeted therapy may aggravate this condition. Asiatic acid (AA), a pentacyclic triterpenoid acid, can effectively protect the liver from hepatic disorders. However, the pharmaceutical application of AA is limited by low oral bioavailability and poor targeting efficiency. This study synthesized a novel liver-targeting material from PEG-SA, chemically linked to ursodeoxycholic acid (UA), and utilized it to modify AA nanostructured lipid carriers (UP-AA-NLC) with enhanced targeting and improved efficacy. The formulation of UP-AA-NLC was optimized via the Box–Behnken Experimental Design (BBD) and characterized by size, zeta potential, TEM, DSC, and XRD. Furthermore, in vitro antifibrotic activity and proliferation of AA and NLCs were assessed in LX-2 cells. The addition of UP-AA-NLC significantly stimulated the TGF-beta1-induced expression of α-SMA, FN1, and Col I α1. In vivo near-infrared fluorescence imaging and distribution trials in rats demonstrated that UP-AA-NLC could significantly improve oral absorption and liver-targeting efficiency. Oral UP-AA-NLC greatly alleviated carbon tetrachloride-induced liver injury and fibrosis in rats in a dosage-dependent manner, as reflected by serum biochemical parameters (AST, ALT, and ALB), histopathological features (H&E and Masson staining), and antioxidant activity parameters (SOD and MDA). Also, treatment with UP-AA-NLC lowered liver hydroxyproline levels, demonstrating a reduction of collagen accumulation in the fibrotic liver. Collectively, optimized UP-AA-NLC has potential application prospects in liver-targeted therapy and holds great promise as a drug delivery system for treating liver diseases.     

固体脂质纳米粒和纳米结构脂质载体在经皮给药系统中的研究进展

目的介绍固体脂质纳米粒和纳米结构脂质载体在经皮给药系统中的应用与优势,为其开发利用提供参考。方法查阅国内外相关文献共30余篇,从固体脂质纳米粒和纳米结构脂质载体用于经皮给药系统的优势、药物在固体脂质纳米粒和纳米结构脂质载体中的分布形式及固体脂质纳米粒和纳米结构脂质载体在经皮给药领域中的应用等方面进行综述。结果固体脂质纳米粒和纳米结构脂质载体可以增强药物稳定性,能在皮肤表面产生包封效应,增加皮肤水合作用,具有药物靶向性。结论固体脂质纳米粒和纳米结构脂质载体是极有发展前景的新型经皮给药系统。     

Mucoadhesive chitosan-coated nanostructured lipid carriers for oral delivery of amphotericin B

This study describes the properties of an amphotericin B-containing mucoadhesive nanostructured lipid carrier (NLC), with the intent to maximize uptake within the gastrointestinal tract. We have reported previously that lipid nanoparticles can significantly improve the oral bioavailability of amphotericin B (AmpB). On the other hand, the aggregation state of AmpB within the NLC has been ascribed to some of the side effects resulting from IV administration. In the undissolved state, AmpB (UAmpB) exhibited the safer monomeric conformation in contrast to AmpB in the dissolved state (DAmpB), which was aggregated. Chitosan-coated NLC (ChiAmpB NLC) presented a slightly slower AmpB release profile as compared to the uncoated formulation, achieving 26.1% release in 5?hours. Furthermore, the ChiAmpB NLC formulation appeared to prevent the expulsion of AmpB upon exposure to simulated gastrointestinal pH media, whereby up to 63.9% of AmpB was retained in the NLC compared to 56.1% in the uncoated formulation. The ChiAmpB NLC demonstrated mucoadhesive properties in pH 5.8 and 6.8. Thus, the ChiAmpB NLC formulation is well-primed for pharmacokinetic studies to investigate whether delayed gastrointestinal transit may be exploited to improve the systemic bioavailability of AmpB, whilst simultaneously addressing the side-effect concerns of AmpB.     

Anti-inflammatory activity of injectable dexamethasone acetate-loaded nanostructured lipid carriers

This work studied the intravenous injection formulation of nanostructured lipid carriers (NLCs) loaded with dexamethasone acetate (DA), a poorly water-soluble drug. The goal of this study was to design nanoparticles which could improve therapeutic efficacy of DA on inflammations. Based on the optimized results of single-factor screening experiment, DA-loaded NLCs (DA-NLCs) prepared by an emulsification-ultrasound method were found to be relatively uniform in size (178?±?4?nm) with a negative zeta potential (-38?±?4 mV). The average drug entrapment efficiency was 91?±?3 %. In vitro release tests indicated DA-NLCs possessed a sustained release characteristic and the accumulative release percentage was near 80 % at 23?h. DA-NLCs exhibited an average peak concentration of DA (7.6 μg/ml) in the pleural exudate after intravenous administration to an experimental model of γ-carrageenan-induced pleuritis rats, which was 8.3 times higher than that of free DA (0.9 μg/ml). The γ-carrageenan-induced edema test showed that the anti-acute inflammatory activity of DA-NLCs was stronger than that of free drug at the same drug concentration (P<0.05). In addition, biodistribution results clearly indicated that DA-NLCs preferentially accumulated in mice livers and lungs after intravenous injection. These results revealed that injectable NLCs may serve as a promising carrier for DA, greatly enhancing the selective effect on inflammatory sites, reducing systematic side effects and may be a potential carrier to increase therapeutic efficacy on inflammatory diseases.     

Co-delivery of etoposide and curcumin by lipid nanoparticulate drug delivery system for the treatment of gastric tumors

Context: Gastric carcinoma (GC) is one of the most common cancers and the second most frequent cause of cancer-related deaths. Chemotherapy is an important therapeutic modality for GC. However, chemoresistance limited its success rate. Combination chemotherapy is often applied to prevent drug-induced resistance in cancers.

Objective: The aim of this study is to evaluate whether the co-delivery of etoposide (ETP) and curcumin (CUR) with one nanoparticle can result in synergistic effects of both drugs.

Methods: ETP- and CUR-loaded nanostructured lipid carriers (ETP-CUR-NLC) were prepared by the solvent injection technique. Their average size, zeta potential and drug loading were evaluated. Human gastric cancer cell lines (SGC7901 cells) were used for the testing of in vitro cytotoxicity studies, and in vivo anti-tumor efficacies of the carriers were evaluated on mice bearing SGC7901 cells xenografts.

Results: ETP-CUR-NLC has a particle size of 114?nm, EPT-loading quantity of 83% and CUR-loading quantity of 82%. ETP-CUR-NLC displayed high cytotoxicity and enhanced antitumor activity in vitro and in vivo. Meanwhile, ETP-CUR-NLC displayed low cytotoxicity in normal tissues in vivo.

Discussion and conclusion: The results demonstrate that ETP-CUR-NLC can achieve impressive anti-tumor activity. By combining CUR, an effective NF-κB inhibitor, with ETP, a powerful anticancer drug, in NLC, we could improve the therapeutic efficacy in cancer treatments. Our results showed that such co-loaded delivery systems could serve as a promising therapeutic approach to improve clinical outcomes against various malignancies.     

Long circulation nanostructured lipid carriers for gambogenic acid: formulation design,characterization, and pharmacokinetic

1.?GNA-PEG-NLC and GNA-NLC were prepared by emulsification and low-temperature solidification methods. The optimized GNA-PEG-NLC and GNA-NLC were not only found to have small mean size (146.33?±?2.11 and 144.07?±?1.44) nm, high Zeta potential (?25.10?±?1.35 and ?28.03?±?0.29) mV, but also great entrapment efficiency (79.07?±?1.11 and 84.65?±?0.98%). TEM proved that particles were nearly spherical with smooth surface shape. Furthermore, in vitro release revealed a burst release initially, followed by a sustained profiles up to 48?h, and the cumulative drug release of GNA-PEG-NLC and GNA-NLC was 65.90?±?2.34% and 69.25?±?1.77%, respectively.

2.?In pharmacokinetic, GNA-PEG-NLC exhibited prolonged MRT and higher AUC values compared with GNA-NLC and GNA solution. Moreover, the tissue distribution demonstrated a high uptake of GNA-PEG-NLC in stomach.

3.?These results indicated that PEG-NLC is a promising delivery system for GNA, which could prolong drug circulation time in body and thus improved its bioavailability.     

Atorvastatin-loaded nanostructured lipid carriers (NLCs): strategy to overcome oral delivery drawbacks

Atorvastatin (AT) is a widely used lipid-regulating drug to reduce cholesterol and triglycerides. Its poor aqueous solubility and hepatic metabolism require development of drug delivery systems able to improve its solubility and bypass hepatic effect. For this purpose, atorvastatin nanostructured lipid carriers (AT-NLCs) were prepared and characterized. AT-NLCs were prepared by emulsification using high-speed homogenization followed by ultrasonication. The prepared NLCs showed particle size between 162.5?±?12 and 865.55?±?28?nm while zeta potential values varied between ?34?±?0.29 and ?23?±?0.36?mV. They also showed high encapsulation efficiency (>87%) and amorphous state of the drug in lipid matrix. Pharmacokinetic parameters of optimized formulation (NLC-1; composed of 2% Gelucire^® 43/01, 8% Capryol^® PGMC, 2% Pluronic^®F68 and 0.5% lecithin) revealed 3.6- and 2.1-fold increase in bioavailability as compared to atorvastatin suspension and commercial product (Lipitor^®), respectively. Administration of NLC-1 led to significant reduction (p?in vivo performance of AT.     

纳米结构脂质载体肺部给药研究进展

传统吸入疗法不能使药物靶向到肺的特定部位,而纳米载体药物的肺部给药系统可克服传统吸入药物的不足。其中纳米结构脂质载体是固体和液体脂质的混合物经表面活性剂乳化后形成的纳米粒,具有更好的胶体稳定性和持续的药物释放行为。其组成成分具有无毒、生理惰性和生物相容性的特点,还具有良好的雾化特性,特别适用于肺部应用,并且生产过程简单（高压均质）,适合大规模生产。本文介绍了常见肺部给药纳米载体,概述了纳米结构脂质载体应用于肺部的优势,为其在肺部给药领域中的深度开发提供参考。     

Preparation and characteristics of oridonin-loaded nanostructured lipid carriers as a controlled-release delivery system

In order to improve drug entrapment efficiency and loading capacity, nanostructured lipid carriers consisting of solid lipid and liquid lipid as a new type of colloidal drug delivery system were prepared. The dispersions of oridonin-loaded solid lipid nanoparticles and nanostructured lipid carriers were successfully prepared by the emulsion-evaporation and low temperature-solidification technique using monostearin as the solid lipid, caprylic/capric triglycerides as the liquid lipid and oridonin as the model drug. Their physicochemical properties of oridonin-loaded nanostructured lipid carriers and release behaviours were investigated and compared with those of solid lipid nanoparticles. As a result, the mean particle size was ～200 nm with narrow polydispersity index lower than 0.4 for all developed formulations. Zeta potential values were in the range ?35 mV ～ ?50 mV, providing good physical stability of all formulations. The differential scanning calorimetry and X-ray diffraction analysis results demonstrated lipid nanoparticles exhibited crystal order disturbance and thus left more space to accommodate drug molecules. The improved drug entrapment efficiency and loading capacity were observed for nanostructured lipid carriers and they enhanced with increasing the caprylic/capric triglycerides content. In vitro drug release experiments exhibited biphasic drug release patterns with burst release initially and prolonged release afterwards. These results indicated that nanostructured lipid carriers could potentially be exploited as a delivery system with improved drug entrapment efficiency and controlled drug release.     

Solid lipid nanoparticles for ocular drug delivery

Ocular drug delivery remains challenging because of the complex nature and structure of the eye. Conventional systems, such as eye drops and ointments, are inefficient, whereas systemic administration requires high doses resulting in significant toxicity. There is a need to develop novel drug delivery carriers capable of increasing ocular bioavailability and decreasing both local and systemic cytotoxicity. Nanotechnology is expected to revolutionize ocular drug delivery. Many nano-structured systems have been employed for ocular drug delivery and yielded some promising results. Solid lipid nanoparticles (SLNs) have been looked at as a potential drug carrier system since the 1990s. SLNs do not show biotoxicity as they are prepared from physiological lipids. SLNs are especially useful in ocular drug delivery as they can enhance the corneal absorption of drugs and improve the ocular bioavailability of both hydrophilic and lipophilic drugs. SLNs have another advantage of allowing autoclave sterilization, a necessary step towards formulation of ocular preparations. This review outlines in detail the various production, characterization, sterilization, and stabilization techniques for SLNs. In-vitro and in-vivo methods to study the drug release profile of SLNs have been explained. Special attention has been given to the nature of lipids and surfactants commonly used for SLN production. A summary of previous studies involving the use of SLNs in ocular drug delivery is provided, along with a critical evaluation of SLNs as a potential ocular delivery system.     

星点设计效应面法优化氟比洛芬纳米结构脂质载体的处方

目的采用星点设计法以总评"归一值"为指标优化氟比洛芬纳米结构脂质载体的处方。方法以粒径、包封率、载药量、Zeta电位等为评价指标,考察了氟比洛芬(flurbiprofen,FP)加入量、卵磷脂用量、吐温-80和泊洛沙姆188的总量以及去氧胆酸钠的用量对FP-NLC性质的影响。用多元线性方程和二次多项式描述各指标及总评"归一值"和3个影响因素之间的数学关系,根据总评"归一值"的最佳数学模型描绘效应面,选择最佳处方,并进行预测分析。结果 4个影响因素和4个评价指标及总评"归一值"之间存在定量关系。优选的最佳处方为氟比洛芬0.222 g,卵磷脂0.300 g,吐温-80和泊洛沙姆188总质量2.000 g,去氧胆酸钠0.100 g。优化处方各指标的预测值和目标值接近。结论所建立的模型预测性良好,可用于预测和优化氟比洛芬纳米结构脂质载体处方。     

Application of lipid nanoparticles to ocular drug delivery

ABSTRACT

Introduction: Although eye drops are widely used as drug delivery systems for the anterior segment of the eye, they are also associated with poor drug bioavailability due to transient contact time and rapid washout by tearing. Moreover, effective drug delivery to the posterior segment of the eye is challenging, and alternative routes of administration (periocular and intravitreal) are generally needed, the blood–retinal barrier being the major obstacle to systemic drug delivery.

Areas covered: Nanotechnology, and especially lipid nanoparticles, can improve the therapeutic efficiency, compliance and safety of ocular drugs, administered via different routes, to both the anterior and posterior segment of the eye. This review highlights the main ocular barriers to drug delivery, as well as the most common eye diseases suitable for pharmacological treatment in which lipid nanoparticles have proved efficacious as alternative delivery systems.

Expert opinion: Lipid-based nanocarriers are among the most biocompatible and versatile means for ocular delivery. Mucoadhesion with consequent increase in pre-corneal retention time, and enhanced permeation due to cellular uptake by corneal epithelial cells, are the essential goals for topical lipid nanoparticle delivery. Gene delivery to the retina has shown very promising results after intravitreal administration of lipid nanoparticles as non-viral vectors.     

Vincristine and temozolomide combined chemotherapy for the treatment of glioma: a comparison of solid lipid nanoparticles and nanostructured lipid carriers for dual drugs delivery

Context: Glioma is a common malignant brain tumor originating in the central nervous system. Efficient delivery of therapeutic agents to the cells and tissues is a difficult challenge. Co-delivery of anticancer drugs into the cancer cells or tissues by multifunctional nanocarriers may provide a new paradigm in cancer treatment.

Objective: In this study, solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were constructed for co-delivery of vincristine (VCR) and temozolomide (TMZ) to develop the synergetic therapeutic action of the two drugs. The antitumor effects of these two systems were compared to provide a better choice for gliomatosis cerebri treatment.

Methods: VCR- and TMZ-loaded SLNs (VT-SLNs) and NLCs (VT-NLCs) were formulated. Their particle size, zeta potential, drug encapsulation efficiency (EE) and drug loading capacity were evaluated. The single TMZ-loaded SLNs and NLCs were also prepared as contrast. Anti-tumor efficacies of the two kinds of carriers were evaluated on U87 malignant glioma cells and mice bearing malignant glioma model.

Results: Significantly better glioma inhibition was observed on NLCs formulations than SLNs, and dual drugs displayed the highest antitumor efficacy in vivo and in vitro than all the other formulations used.

Conclusion: VT-NLCs can deliver VCR and TMZ into U87MG cells more efficiently, and inhibition efficacy is higher than VT-SLNs. This dual drugs-loaded NLCs could be an outstanding drug delivery system to achieve excellent therapeutic efficiency for the treatment of malignant gliomatosis cerebri.     

星点设计-效应面法优化依托泊苷自微乳化释药系统

目的 研制稳定的依托泊苷自微乳制剂并评价其质量.方法 通过溶解度试验、处方配比、三元相图的绘制及星点设计-效应面法的优化,以粒径、溶解度和zeta电位为指标,筛选各组分的最佳组合和处方配比,并对依托泊苷自微乳的理化性质和体外溶出进行测定.结果 依托泊苷自微乳最佳处方为:依托泊苷(2.0％)、Capryol 90(15.1％)、Cremophor RH40(30.4％)、Transcutol HP(52.5％),平均粒径为18.31 nm,自乳化时间＜1min,乳化后载药量＞ 25 mg· mL-1.结论 制备的依托泊苷自微乳稳定性好,载药量高.     

Preparation,characterization and biodistribution of nanostructured lipid carriers for parenteral delivery of bifendate

Nanostructured lipid carrier (NLC)-loaded bifendate (DDB) was prepared by melt-emulsification method to improve drug payloads and liver targeting. The particle size of the prepared formulation analysed by photon correlation spectroscopy (PCS) was 217.4?nm with a narrow polydispersity index (PI) lower than 0.2, meanwhile the loading capacity increased from 4.3% to 15.7% in comparison with DDB-loaded SLN reported in previous study. The zeta potential value was ?21.91?mV, and transmission electron microscopy studies revealed NLC of irregularly spherical shape. With respect to lipid polymorphism, a less ordered structure of NLC was confirmed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). In addition, tissue distribution of DDB-loaded NLC and DDB solution were carried out in Kunming strain mice. In tested organs, the distribution of DDB-loaded NLC to liver was higher than that of free drug. These results support the potential applications of NLC for the delivery of DDB.