Preparation and in vitro evaluation of thienorphine-loaded PLGA nanoparticles

Sustained Drug Release from Smart Nanoparticles in Cancer Therapy: A Comprehensive Review

Although nanomedicine has been highly investigated for cancer treatment over the past decades, only a few nanomedicines are currently approved and in the market; making this field poorly represented in clinical applications. Key research gaps that require optimization to successfully translate the use of nanomedicines have been identified, but not addressed; among these, the lack of control of the release pattern of therapeutics is the most important. To solve these issues with currently used nanomedicines (e.g., burst release, systemic release), different strategies for the design and manufacturing of nanomedicines allowing for better control over the therapeutic release, are currently being investigated. The inclusion of stimuli-responsive properties and prolonged drug release have been identified as effective approaches to include in nanomedicine, and are discussed in this paper. Recently, smart sustained release nanoparticles have been successfully designed to safely and efficiently deliver therapeutics with different kinetic profiles, making them promising for many drug delivery applications and in specific for cancer treatment. In this review, the state-of-the-art of smart sustained release nanoparticles is discussed, focusing on the design strategies and performances of polymeric nanotechnologies. A complete list of nanomedicines currently tested in clinical trials and approved nanomedicines for cancer treatment is presented, critically discussing advantages and limitations with respect to the newly developed nanotechnologies and manufacturing methods. By the presented discussion and the highlight of nanomedicine design criteria and current limitations, this review paper could be of high interest to identify key features for the design of release-controlled nanomedicine for cancer treatment.

Design and evaluation of hyaluronic acid-coated PLGA nanoparticles of raloxifene hydrochloride for treatment of breast cancer

CONTEXT

In the present study, hyaluronic acid (HA)-coated raloxifene-loaded poly(l-lactic-co-glycolic acid) (PLGA) nanoparticles have been developed to improve the anticancer potential and reduce side effects associated with the drug.

AIM AND OBJECTIVES

The investigation was aimed to formulate and optimize raloxifene hydrochloride (RALH)-loaded PLGA nanoparticles with surface modification using HA as a targeting moiety. To perform physicochemical characterization, in vitro cytotoxicity study (using MCF-7), in vitro drug release study and in vivo pharmacodynamic study of optimized formulation.

METHODOLOGY

Raloxifene hydrochloride-loaded PLGA nanoparticles were prepared by nanoprecipitation technique, followed by surface modification with HA. Formulation was optimized by using 23 factorial design and characterized by physicochemical, in vitro drug release, in vitro cytotoxicity studies, and in vivo pharmacokinetics.

RESULTS AND DISCUSSION

The particle size, PDI, zeta potential, entrapment efficiency, and loading capacity of spherically shaped RALH-loaded nanoparticles were 207.3 ± 4.2 d.nm, 0.218 ± 0.127, -.127 mV, 43.75 ± 1.2%, and 7.55 ± 1.14%, respectively. The in vitro drug release showed sustained release and followed Korsmeyer-Peppas model with non-Fickian release pattern. The in vitro cytotoxicity study of drug-loaded NPs by MTT assay on MCF-7 breast carcinoma cell showed anti-cancer activity after 48 h of treatment.

CONCLUSION

The results of the present investigation suggested that RALH-loaded HA-modified PLGA nanoparticles showed sustained drug release with anticancer activity and can be a promising approach for treatment of breast cancer.

Quaternary ammonium silane, calcium and phosphorus-loaded PLGA submicron particles against Enterococcus faecalis infection of teeth: An in vitro and in vivo study

Refractory root canal infection of human teeth is the primary cause of dental treatment failure. Enterococcus faecalis is the major cause of refractory root canal infection. In the present study, poly(D,L-lactic-co-glycolide) (PLGA) submicron particles were used as carriers to deliver an antimicrobial quaternary ammonium silane (code-named K21) as well as calcium and phosphorus elements. The release profiles, antibacterial ability against E. faecalis, extent of infiltration into dentinal tubules, biocompatibility and in vitro mineralization potential of the particles were investigated. In addition, the antimicrobial effects of the particles against E. faecalis infection were evaluated in vivo in the teeth of beagle dogs. The encapsulated components were released from the PLGA particles in a sustained-release manner. The particles also displayed good biocompatibility, in vitro mineralization ability and antibacterial activity against E. faecalis. The particles could be driven into dentinal tubules of dentin slices by ultrasonic activation and inhibited E. faecalis colonization. In the root canals of beagle dogs, PLGA submicron particles loaded with K21, calcium and phosphorus demonstrated strong preventive effects against E. faecalis infection. The system may be developed into a new intracanal disinfectant for root canal treatment.

A comparison of models for the analysis of the kinetics of drug release from PLGA-based nanoparticles

Purpose

Poly (lactic-co-glycolic acid) has received much academic attention for developing nanotherapeutics and FDA has approved it for several applications. An important parameter that dictates the bioavailability and hence the biological effect of the drug is drug release from its delivering system. This study offers a comparative mathematical analysis of drug release from Poly (lactic-co-glycolic acid)–based nanoparticles to suggest a general model explaining multi-mechanistic release they provide.

Methods

Eight release models, zero order, first order, Higuchi, Hixson-Crowell, the square root of mass, the three-second root of mass, Weibull and Korsmeyer-Peppas, as well as the second degree polynomial equation were applied to 60 data sets. The models analysed regarding several types of errors, regression parameters and average Akaike information criterion.

Results and discussion

Most of the data sets present the highest R², the lowest overall error and AIC for the Weibull model. Weibull model with the mean AIC = -36.37 and mean OE = 7.24 and the highest NE less than 5, 10, 15 and 20 % in most of the cases best fits the release data from various PLGA-based drug delivery systems that are studied. Weibull model seems to show enough flexibility to describe various release patterns PLGA provides.

Application of a Quality-By-Design Approach to Optimise Lipid-Polymer Hybrid Nanoparticles Loaded with a Splice-Correction Antisense Oligonucleotide: Maximising Loading and Intracellular Delivery

BACKGROUND

Antisense oligonucleotides (ASOs) are promising therapeutics for specific modulation of cellular RNA function. However, ASO efficacy is compromised by inefficient intracellular delivery. Lipid-polymer hybrid nanoparticles (LPNs) are attractive mediators of intracellular ASO delivery due to favorable colloidal stability and sustained release properties.

METHODS

LPNs composed of cationic lipidoid 5 (L₅) and poly(DL-lactic-co-glycolic acid) were studied for delivery of an ASO mediating splice correction of a luciferase gene transcript (Luc-ASO). Specific purposes were: (i) to increase the mechanistic understanding of factors determining the loading of ASO in LPNs, and (ii) to optimise the LPNs and customise them for Luc-ASO delivery in HeLa pLuc/705 cells containing an aberrant luciferase gene by using a quality-by-design approach. Critical formulation variables were linked to critical quality attributes (CQAs) using risk assessment and design of experiments, followed by delineation of an optimal operating space (OOS).

RESULTS

A series of CQAs were identified based on the quality target product profile. The L₅ content and L₅:Luc-ASO ratio (w/w) were determined as critical formulation variables, which were optimised systematically. The optimised Luc-ASO-loaded LPNs, defined from the OOS, displayed high loading and mediated splice correction at well-tolerated, lower doses as compared to those required for reference L₅-based lipoplexes, L₅-modified stable nucleic acid lipid nanoparticles or LPNs modified with dioleoyltrimethylammonium propane (conventional cationic lipid).

CONCLUSIONS

The optimal Luc-ASO-loaded LPNs represent a robust formulation that mediates efficient intracellular delivery of Luc-ASO. This opens new avenues for further development of LPNs as a broadly applicable technology platform for delivering nucleic acid cargos intracellularly.

Chitosan-functionalized lipid-polymer hybrid nanoparticles for oral delivery of silymarin and enhanced lipid-lowering effect in NAFLD

Background

Non-alcoholic fatty liver disease (NAFLD) is a chronic disease that causes excessive hepatic lipid accumulation. Reducing hepatic lipid deposition is a key issue in treatment and inhibition of NAFLD evolution. Silymarin is a potent hepatoprotective agent; however, it has low oral bioavailability due to its poor aqueous solubility and low membrane permeability. Unfortunately, few studies have addressed the development of convenient oral nanocarriers that can efficiently deliver silymarin to the liver and enhance its lipid-lowering effect. We designed silymarin-loaded lipid polymer hybrid nanoparticles containing chitosan (CS-LPNs) to improve silymarin bioavailability and evaluated their lipid-lowering effect in adiponutrin/patatin-like phospholipase-3 I148M transgenic mice, an NAFLD model.

Results

Compared to chitosan-free nanoparticles, CS-LPNs showed 1.92-fold higher uptake by fatty liver cells. Additionally, CS-LPNs significantly reduced TG levels in fatty liver cells in an in vitro lipid deposition assay, suggesting their potential lipid-lowering effects. The oral bioavailability of silymarin from CS-LPNs was 14.38-fold higher than that from suspensions in rats. Moreover, compared with chitosan-free nanoparticles, CS-LPNs effectively reduced blood lipid levels (TG), improved liver function (AST and ALT), and reduced lipid accumulation in the livers of mice in vivo. Reduced macrovesicular steatosis in pathological tissue after CS-LPN treatment indicated their protective effect against liver steatosis in NAFLD.

Conclusions

CS-LPNs enhanced oral delivery of silymarin and exhibited a desirable lipid-lowering effect in a mouse model. These findings suggest that CS-LPNs may be a promising oral nanocarrier for NAFLD therapeutics.

Electronic supplementary material

The online version of this article (10.1186/s12951-018-0391-9) contains supplementary material, which is available to authorized users.

Assessment of synergistic effect of combining hyperthermia with irradiation and calcium carbonate nanoparticles on proliferation of human breast adenocarcinoma cell line (MCF-7 cells)

The present study was undertaken to evaluate the synergistic effect of combining hyperthermia with irradiation and calcium carbonate nanoparticles (CC NPs) on proliferation of MCF-7 cells. The cells were randomly allocated to 19 groups: one negative control, three positive controls and 15 treatment groups. MCF-7 cells were treated with three concentrations of CC NPs (50, 100 and 150 μg/mL), gamma radiation (200 cGy), hyperthermia (41 °C for 1 h) and three concentrations of doxorubicin (200, 400 and 800 nm) and incubated at 37 °C for 24 h. Then the cell viability, the percentage of apoptosis and the levels of caspase-3, -8 and -9 proteins were measured. The results indicated that the combination group (150 µg/mL CC NPs + thermoradiotherapy) had a significant (p < .001) decrease in cell viability (48.65 ± 4.8%) and a significant (p < .001) increase in apoptosis percentage (45 ± 1.63%) of MCF-7 cells, as compared with the negative control and most of the other treatment groups. Moreover, a significant (p < .05) increase was observed in the activity of caspase-3 and caspase-9. Our findings revealed that CC NPs in combination with irradiation and hyperthermia could significantly reduce the cell viability and enhance the apoptosis of the MCF-7 breast cancer cells, the same as doxorubicin anti-cancer drug.