Targeted killing of CD133+ lung cancer stem cells using paclitaxel-loaded PLGA-PEG nanoparticles with CD133 aptamers / 南方医科大学学报

OBJECTIVE@#To construct a polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) nanocarrier (N-Pac-CD133) coupled with a CD133 nucleic acid aptamer carrying paclitaxel for eliminating lung cancer stem cells (CSCs).@*METHODS@#Paclitaxel-loaded N-Pac-CD133 was prepared using the emulsion/solvent evaporation method and characterized. CD133+ lung CSCs were separated by magnetic bead separation and identified for their biological behaviors and gene expression profile. The efficiency of paclitaxel-loaded N-Pac-CD133 for targeted killing of lung cancer cells was assessed in vitro. SCID mice were inoculated with A549 cells and received injections of normal saline, empty nanocarrier linked with CD133 aptamer (N-CD133), paclitaxel, paclitaxel-loaded nanocarrier (N-Pac) or paclitaxel-loaded N-Pac-CD133 (n=8, 5 mg/kg paclitaxel) on days 10, 15 and 20, and the tumor weight and body weight of the mice were measured on day 40.@*RESULTS@#Paclitaxel-loaded N-Pac-CD133 showed a particle size of about 100 nm with a high encapsulation efficiency (>80%) and drug loading rate (>8%), and was capable of sustained drug release within 48 h. The CD133+ cell population in lung cancer cells showed the characteristic features of lung CSCs, including faster growth rate (30 days, P=0.001) and high expressions of tumor stem cell markers OV6(P < 0.001), CD133 (P=0.001), OCT3/4 (P=0.002), EpCAM (P=0.04), NANOG (P=0.005) and CD44 (P=0.02). Compared with N-Pac and free paclitaxel, paclitaxel-loaded N-Pac-CD133 showed significantly enhanced targeting ability and cytotoxicity against lung CSCs in vitro (P < 0.001) and significantly reduced the formation of tumor spheres (P < 0.001). In the tumor-bearing mice, paclitaxel-loaded N-Pac-CD133 showed the strongest effects in reducing the tumor mass among all the treatments (P < 0.001).@*CONCLUSION@#CD133 aptamer can promote targeted delivery of paclitaxel to allow targeted killing of CD133+ lung CSCs. N-Pac-CD133 loaded with paclitaxel may provide an effective treatment for lung cancer by targeting the lung cancer stem cells.

Preparation of tanshinone Ⅱ_A-glycyrrhetinic acid solid lipid nanoparticles and its inhibitory effect on acne / 中国中药杂志

The optimal prescription of tanshinone Ⅱ_A(TSN)-glycyrrhetinic acid(GA) solid lipid nanoparticles(GT-SLNs) was explored and evaluated in vivo and in vitro, and its effect on acne after oral administration was investigated. The preparation processing and prescription were optimized and verified by single factor and response surface methodology. The in vitro release of GA and TSN in GT-SLNs was determined by ultra-performance liquid chromatography(UPLC). The effect of GT-SLNs on acne was investigated by the levels of sex hormones in mice, ear swelling model, and tissue changes in sebaceous glands, and the pharmacokinetics was evaluated. The 24-hour cumulative release rates of GA and TSN in SLNs were 65.87%±5.63% and 36.13%±2.31% respectively. After oral administration of GT-SLNs and the mixture of GA and TSN(GT-Mix), the AUC_(0-t) and AUC_(0-∞) of TSN in GT-SLNs were 1.98 times and 4.77 times those in the GT-Mix group, respectively, and the peak concentration of TSN in the GT-SLNs group was 17.2 times that in the GT-Mix group. After intragastric administration of GT-SLNs, the serum levels of testosterone(T) and the ratio of testosterone to estradiol(T/E2) in the GT-SLNs group significantly declined, and the sebaceous glands of mice were atrophied to a certain extent. The results demonstrated that obtained GT-SLNs with good encapsulation efficiency and uniform particle size could promote the release of GA and TSN. GT-SLNs displayed therapeutic efficacy on acne manifested by androgen increase, abnormal sebaceous gland secretion, and inflammatory damage.

Formulation optimization of emodin nanostructured lipid carriers by Box-Behnken response surface method and in vitro quality evaluation / 中国中药杂志

Emodin nanostructured lipid carriers(ED-NLC) were prepared and their quality was evaluated in vitro. Based on the results of single-factor experiments, the ED-NLC formulation was optimized by Box-Behnken response surface method with the dosages of emodin, isopropyl myristate and poloxamer 188 as factors and the nanoparticle size, encapsulation efficiency and drug loading as evaluation indexes. Then the evaluation was performed on the morphology, size and in vitro release of the nanoparticles prepared by emulsification-ultrasonic dispersion method in line with the optimal formulation, i.e., 3.27 mg emodin, 148.68 mg isopropyl myristate and 173.48 mg poloxamer 188. Under a transmission electron microscope(TEM), ED-NLC were spherical and their particle size distribution was uniform. The particle size of ED-NLC was(97.02±1.55) nm, the polymer dispersion index 0.21±0.01, the zeta potential(-38.96±0.65) mV, the encapsulation efficiency 90.41%±0.56% and the drug loading 1.55%±0.01%. The results of differential scanning calorimeter(DSC) indicated that emodin may be encapsulated into the nanostructured lipid carriers in molecular or amorphous form. In vitro drug release had obvious characteristics of slow release, which accorded with the first-order drug release equation. The fitting model of Box-Behnken response surface methodology was proved accurate and reliable. The optimal formulation-based ED-NLC featured concentrated particle size distribution and high encapsulation efficiency, which laid a foundation for the follow-up study of ED-NLC in vivo.

Progresses on active targeting liposome drug delivery systems for tumor therapy / 生物医学工程学杂志

Liposome is an ideal drug carrier with many advantages such as excellent biocompatibility, non-immunogenicity, and easy functionalization, and has been used for the clinical treatment of many diseases including tumors. For the treatment of tumors, liposome has some passive targeting capability, but the passive targeting effect alone is very limited in improving the drug enrichment in tumor tissues, and active targeting is an effective strategy to improve the drug enrichment. Therefore, active targeting liposome drug-carriers have been extensively studied for decades. In this paper, we review the research progresses on active targeting liposome drug-carriers based on the specific binding of the carriers to the surface of tumor cells, and summarize the opportunities, challenges and future prospects in this field.

Nanopartículas como transportadores de fármacos: una herramienta prometedora contra la tuberculosis / Nanoparticles as drug transporters: a promising tool against tuberculosis

RESUMEN La Organización Mundial de la Salud (OMS) ubica a la tuberculosis (TB) como uno de los problemas de salud más preocupantes en la actualidad, y señala que se requieren de acciones novedosas para controlar su expansión y, de esta manera, alcanzar una de las metas establecidas en los Objetivos de Desarrollo Sostenible: reducir para 2030 la morbilidad e incidencia de TB. Para lograr este objetivo, está claro que las herramientas empleadas actualmente para su diagnóstico y tratamiento ya no son las adecuadas. En este sentido, es necesario desarrollar nuevos medicamentos y vacunas, así como novedosos procedimientos de administración de fármacos que generen una mejor respuesta, disminuyan el tiempo y optimicen los tratamientos. La nanotecnología ha incorporado en los últimos años un gran número de nuevas herramientas que incrementan considerablemente, la diversidad de mecanismos para la administración de tratamientos antituberculosos. Dicho esto, la presente revisión describe brevemente el estado actual de la farmacorresistencia en TB, así como las características generales de las nanopartículas que están evaluándose como herramientas para transportar antibióticos antituberculosos.

ABSTRACT The World Health Organization (WHO) places Tuberculosis (TB) as one of the most important health problems today. According to the WHO, this disease requires novel actions to control its expansion and, in this way, achieve one of the goals established in the sustainable development goals: to reduce TB morbidity and incidence by 2030 and regain control. To achieve this goal, the tools currently used for diagnosis and treatment are no longer adequate. In this sense, it is necessary to develop new drugs and vaccines, as well as novel drug administration procedures that generate a better response, reduce times, and optimize treatments. Nanotechnology has incorporated in recent years a considerable number of new tools that significantly increase the diversity of mechanisms for the administration of anti-tuberculosis drugs. Therefore, the present review briefly describes the current state of drug resistance in tuberculosis, as well as the general characteristics of nanoparticles being evaluated as tools to transport new antibiotics against tuberculosis.

Preparation of paclitaxel-loaded and folic acid-modified poly (lactic-co-glycolic acid) nano-micelles and in vitro anticancer effect on cervical cancer HeLa cells / 中国中药杂志

The paclitaxel-loaded and folic acid-modified poly(lactic-co-glycolic acid) nano-micelles(PTX@FA-PLGA-NMs) were prepared by the emulsion solvent evaporation method, and the parameters of paclitaxel-loaded nano-micelles were optimized with the particle size and PDI as evaluation indexes. The morphology of the nano-micelles was observed by transmission electron microscopy(TEM), and the stability, drug loading and encapsulation efficiency were systematically investigated. In vitro experiments were performed to study the cytotoxic effects of nano-micelles, apoptosis, and cellular uptake. Under the optimal parameters, the nano-micelles showed the particle size of(125.3±1.2) nm, the PDI of 0.086±0.026, the zeta potential of(-20.0±3.8) mV, the drug loading of 7.2%±0.75%, and the encapsulation efficiency of 50.7%±1.0%. The nano-micelles were in regular spherical shape as observed by TEM. The blank FA-PLGA-NMs exhibited almost no inhibitory effect on the proliferation and growth of tumor cells, while the drug-loaded nano-micelles and free PTX exhibited significant inhibitory effects. The IC_(50) of PTX@FA-PLGA-NMs and PTX was 0.56 μg·mL~(-1) and 0.66 μg·mL~(-1), respectively. The paclitaxel-loaded nano-micelles were potent in inhibiting cell migration as assessed by the scratch assay. PTX@FA-PLGA-NMs had good pro-apoptotic effect on cervical cancer HeLa cells and significantly promoted the uptake of HeLa cells. The results of in vitro experiments suggested that PTX@FA-PLGA-NMs could target and treat cervical cancer HeLa cells. Therefore, as nanodrug carriers, PTX@FA-PLGA-NMs with anti-cancer activity are a promising nano-system for improving the-rapeutic effects on tumors.

Synthesis of folate modified chitosan-based nanomicelles and its anti-tumor activity / 浙江大学学报·医学版

OBJECTIVE@#To design and synthesize folate-modified pH-responsive chitosan-based nanomicelles and investigate the anti-tumor activity of the drug-loaded micelles.@*METHODS@#CHI-DMA was obtained by reductive amination reaction of aldehyde-based chitosan and hydrophilic amine compounds, and CHI-DMA-LA was obtained by condensation reaction with lauric acid; FA-CHI-DMA-LA was obtained after modification with folic acid (FA). The drug-loaded nanomicelles FA-CHI-DMA-LA/DOX were assembled by solvent change method. The physicochemical properties of polymers were characterized by hydrogen nuclear magnetic resonance and transmission electron microscope. The particle size and surface potential were determined by dynamic light scattering method. Folic acid access rate, doxorubicin (DOX) loading rate and entrapped efficiency were measured by UV-vis spectrophotometer. The drug release properties of DOX-loaded micelles were monitored by fluorescence spectrophotometer at different pHs (7.4, 6.5, 5.0). The cytotoxicity against human oral cancer KB cells was detected by MTT assay. Fluorescence microscope and flow cytometry were applied to investigate the phagocytosis of DOX-loaded micelles on KB cells.@*RESULTS@#FA-CHI-DMA-LA was synthesized. The particle sizes of FA-CHI-DMA-LA-1 and FA-CHI-DMA-LA-2 micelles which used for the subsequent experiments were (73±14) nm and (106±15) nm, zeta potential were (15.59±1.98) mV and (21.20±2.35) mV, respectively. The drug loading rates of drug-loaded micelles FA-CHI-DMA-LA-1/DOX and FA-CHI-DMA-LA-2/DOX are (4.08±1.12)%and (4.12±0.44)%, respectively. drug release is pH-responsive, with cumulative release of DOX up to 37%and 36%at pH 5.0, which is about 1.5 times higher than that of pH 7.4. For FA-CHI-DMA-LA micelles with 1.25 to 125 μg/mL concentration, the survival rate of KB cells is more than 70%after incubation for 24 hours. The cell uptake of FA-CHI-DMA-LA/DOX micelles was enhanced compared to CHI-DMA-LA/DOX, and the cell uptake was higher in incubation without FA medium than that with FA. Compared with free DOX or CHI-DMA-LA/DOX, FA-CHI-DMA-LA/DOX nanomicelles showed higher cyctoxicity to KB cells, especially the FA-CHI-DMA-LA-2/DOX nanomicelles, the cell survival rate was about 17% after incubation for 24 hours.@*CONCLUSIONS@#FA-modified chitosan-based nanomicelle with good biocompatibility was successfully prepared, which exhibits tumor microenvironmental pH responsive drug release and tumor targeting.

Prospects and challenges of exosomes as drug delivery systems / 生物医学工程学杂志

Exosomes are nanoscale vectors with a diameter of 30~100 nm secreted by living cells, and they are important media for intercellular communication. Recent studies have demonstrated that exosomes can not only serve as biomarkers for diagnosis, but also have great potential as natural drug delivery vectors. Exosomes can be loaded with therapeutic cargos, including small molecules, proteins, and oligonucleotides. Meanwhile, the unique biological compatibility, high stability, and tumor targeting of exosomes make them attractive in future tumor therapy. Though exosomes can effectively deliver bioactive materials to receptor cells, there is a wide gap between our current understanding of exosomes and their application as ideal drug delivery systems. In this review, we will briefly introduce the function and composition of exosomes, and mainly summarize the potential advantages and challenges of exosomes as drug carriers. Finally, this review is expected to provide new ideas for the development of exosome-based drug delivery systems.

Preparation of evodiamine-glycyrrhizic acid micelles with glycyrrhizic acid as carrier and their anti-hepatic fibrosis activity / 中国中药杂志

This study aimed to prepare evodiamine-glycyrrhizic acid(EVO-GL) micelles to enhance the anti-hepatic fibrosis activity of evodiamine. Firstly, EVO-GL micelles were prepared with use of thin film dispersion method. With particle size, encapsulation efficiency, loading capacity of micelles and the solubility of evodiamine as the indexes, the effect of different factors on micelles was observed to screen the optimal preparation methods and process. Then the pharmaceutical properties and the therapeutic effects of EVO-GL micelles prepared by optimal process were evaluated on CCl_4-induced hepatic fibrosis. The results showed that the micelles prepared by the thin film dispersion method had an even size, with an average particle size of(130.80±12.40)nm, Zeta potential of(-41.61±3.12) mV, encapsulation efficiency of 91.23%±1.22%, drug loading of 8.42%±0.71%, high storage stability at 4 ℃ in 3 months, and slow in vitro release. Experimental results in the treatment of CCl_4-induced hepatic fibrosis in rats showed that EVO-GL micelles had a synergistic anti-hepatic fibrosis effect, which significantly reduced the liver function index of hepatic fibrosis rats. In conclusion, the EVO-GL micelles prepared with glycyrrhizic acid as a carrier would have a potential application prospect for the treatment of hepatic fibrosis.

Effect of ginsenoside Rg_3 nanostructured lipid carrier modified by pullulan on promoting absorption and its anti-tumor evaluation in vitro / 中国中药杂志

Ginsenoside Rg_3 is widely used in clinical practice as an anti-tumor adjuvant drug, but its application is limited due to its poor oral absorption. In this study, we intended to construct a ginsenoside Rg_3 nanostructured lipid carrier modified by the pullulan(PUL-Rg_3-NLC) to improve the adhesion properties of ginsenoside Rg_3, promote the drug uptake and improve the anti-tumor efficacy. PUL-Rg_3-NLC was characterized by morphology, particle size and Zeta potential. In vivo adhesion characteristics were evaluated by oral gavage tests, and the results were verified from multiple perspectives in combination with in vitro uptake behavior and in vitro pharmacodynamics. The results showed that PUL-Rg_3-NLC, with a particle size of(102±1.89) nm, was characterized by gastric adhesion and could be retained in gastric tissues for a long time, and its uptake by BGC-823 cells was promoted mainly through the pathway mediated by the caveolin-mediated endocytosis. In vitro MTT, cell apoptosis, wound-healing assay and invasion assay all showed some anti-tumor effects. Therefore, PUL-Rg_3-NLC can significantly promote the adhesion of Rg_3 in the stomach, promote the uptake of drugs by gastric cancer cells, and improve the anti-tumor effect. This study can provide some reference for the adjuvant treatment of gastric cancer.

In vivo anti-tumor activity of tumor-targeting pH-sensitive lipoprotein-mimic nanocarrier with paclitaxel loaded / 中国中药杂志

Paclitaxel( PTX) is used as a broad spectrum anti-tumor medicine. However,serious drawbacks restrict clinical application of PTX. In this study,we prepared tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier containing paclitaxel( BSALC/DOPE-PTX) to study the effective antitumor activity. The in vivo targeting ability of the nanocarrier in tumor bearing nude mice was evaluated by using a Kodak in vivo imaging system FX PRO. The in vivo anti-tumor activity was evaluated in MDA-MB-231 tumor bearing mice,and representative sections were stained with hematoxylin and eosin( H&E),and examined by light microscopy. The results showed that DiR-loaded FA-BSA-LC/DOPE selectively targeted tumor,and had a relatively long residence in the tumor tissue. According to the in vivo anti-tumor activity study,FA-BSA-LC/DOPE-PTX exhibited an outstanding tumor inhibition effect with a tumor growth inhibition rate of 79.3%,and tumor tissue sections stained by hematoxylin and eosin( HE) showed severe necrosis areas and many dead cells with condensed nuclei in the FA-BSA-LC/DOPE-PTX group. Therefore,FA-BSA-LC/DOPE-PTX is a biocompatible,tumor-targeting and pH-sensitive lipoprotein-mimic nanocarrier,with a very marked anti-tumor activity in tumor-bearing mice in vivo.

Preparation of docetaxel-loaded nanomicelles and their anti-Lewis lung cancer effect in vitro / 中国中药杂志

Docetaxel-loaded nanomicelles were prepared in this study to improve the solubility and tumor targeting effect of docetaxel(DTX),and further evaluate their anticancer effects in vitro. PBAE-DTX nanomicelles were prepared by film-hydration method with amphiphilic block copolymer polyethyleneglycol methoxy-polylactide(PELA) and pH sensitive triblock copolymer polyethyleneglycol methoxy-polylactide-poly-β-aminoester(PBAE) were used respectively to prepare PELA-DTX nanomicelles and PBAE-DTX nanomicelles. The nanomicelles were characterized by physicochemical properties and the activity of mice Lewis lung cancer cells was studied. The results of particle size measurement showed that the blank micelles and drug-loaded micelles had similar particle sizes, ranging from 10 to 100 nm. The particle size of PBAE micelles was changed under weak acidic conditions, with good pH response. The encapsulation efficiency of the above two types of DTX-loaded nanomicelles determined by HPLC was(93.8±1.70)% and(87.2±4.10)%, and the drug loading amount was(5.3±0.10)% and(4.9±0.05)%,respectively. Furthermore,the DTX micelles also showed significant inhibitory effects on Lewis lung cancer cells by MTT assay, and pH-sensitive PBAE-DTX showed better cytotoxicity. The results of flow cytometry indicated that,the apoptosis rate of lung cancer Lewis cells was(20.72±1.47)%,(29.71±2.38)%,and(40.91±1.90)%(P<0.05) at 48 h after treatment in DTX,PELA-DTX,and PBAE-DTX groups. The results showed that different docetaxel preparations could promote the apoptosis of Lewis cells, and PBAE-DTX had stronger apoptotic-promoting effect. The pH-sensitive DTX-loaded micelles are promising candidates in developing stimuli triggered drug delivery systems in acidic tumor micro-environments with improved inhibitory effects of tumor growth on Lewis lung cancer.

Effects of three drying methods on the physical properties and drug delivery in chitosan microspheres / 华西口腔医学杂志

OBJECTIVE@#The purpose of this study is to investigate the effects of different drying methods on the physical properties and drug delivery of chitosan microspheres.@*METHODS@#Three types of drying methods were utilized, including air drying and freeze drying after freezing at -20 ℃ (slow cooling) and at -80 ℃ (fast cooling). The physical properties of microspheres were characterized. Utilizing bovine serum albumin (BSA) as the model drug, the in-vitro release behaviors of drug-loaded beads were investigated.@*RESULTS@#By comparing the physical properties of the different drying methods, the microspheres' diameters, porosities, and surface area were observed to increase successively from air drying and slow cooling to fast cooling, whereas the pore size and the swelling and degradation rates varied. The drug-loading experiments revealed that the loading capacity of air-dried microspheres was the lowest and the release rate was the slowest. Although the loading capacity of fast cooling microspheres was high, an obvious burst release was observed. The loading capacity of slow cooling microspheres was similar to that of the fast cooling microspheres and the loaded BSA can be released continuously.@*CONCLUSIONS@#The results indicate that different drying methods can affect the physical properties of chitosan microspheres, which further influence drug loading and release.

Role of bacterial minicells in cancer therapy / 生物工程学报

Cancer is one of the most important diseases threatening human health. Frequently-used traditional cancer treatment methods, like radiotherapy, chemotherapy and surgery, have serious toxic side effects and limitations. The widely-used drug delivery carriers (liposomes, nanoparticles, etc.) have also possessed many issues such as drug leakage and incomplete loading in the late clinical stage. Currently, using tumor-targeting vectors to deliver anti-tumor drugs or small molecules is one of the promising strategies for mediating safe and effective tumor therapy. In recent years, bacterial-derived non-replicating minicells, which are nanoscale non-nucleated cells produced during abnormal bacterial division, have got more and more attention. With a diameter of 200-400 nm, minicells have a large drug loading capacity. Meanwhile, the surface of minicells are able to be modified to load the assembly of antibodies/ligands that bind to tumor cell surface specific antigens or receptors, which can significantly improve tumor targeting of minicells. This tumor-targeting nanomaterials of minicells not only are used to deliver anti-tumor chemotherapeutic drugs, functional nucleic acids or plasmids encoding functional small molecules to mammalian cells, but also greatly increase drug loading and reduce drug penetration. Thus, the use of minicells combining with chemical therapy could help reduce the toxicity and maximize the effectiveness of the drug in the body. This paper summarizes the research and development of production purification, drug loading, tumor cells targeting, and internalization process of minicells, as well as its use in the delivery of anti-tumor drugs, to provide some information for the development and utilization of minicell carriers.

Construction of engineered exosomes with high loading efficiency of cellular endogenous proteins / 生物工程学报

Exosomes have many advantages as natural drug delivery carriers, but their application is limited by the inefficient loading of intracellular drugs (such as proteins and nucleic acids). In this study, mCherry, a red fluorescent protein, was used as the endogenous cargo target. Through gene modification of donor cells and fusion expression of membrane localization elements (PB, CAAX, Palm and CD63), mCherry was specifically sorted into exosomes through biogenesis. Results show that CD63 had the highest sorting efficiency, followed by Palm. PB and CAAX led enrichment of mCherry on the plasma membrane, but not in exosomes. The approach provides an alternative to facilitate packaging of cargo by exosomes and thus to increase the efficient delivery of endogenous protein drugs.

Effect of cell penetrating peptide TAT-modified liposomes loaded with salvianolic acid B on proliferation,migration and cell cycle of human skin fibroblasts / 中国中药杂志

Hypertrophic scar( HS) is a very common skin fibrosis disorder after human skin injury and wound healing. The objective of this study was to investigate the efficacy of cell penetrating peptide TAT-modified liposomes loaded with salvianolic acid B( SAB-TAT-LIP) on proliferation,migration and cell cycle of human skin fibroblasts( HSF),and preliminarily evaluate its effect on prevention and treatment of HS. HSF were cultured in vitro,and MTT assay was used to detect the inhibitory effect of SAB-TAT-LIP on cell proliferation. Cell migration was assessed by Transwell chamber method and scratch method; and cell cycle change was detected by flow cytometry. In vitro cell studies showed that blank liposome basically had no toxic effect on HSF. Different concentrations of SABTAT-LIP inhibited proliferation on HSF in varying degrees after intervention for different periods in a dose and time dependent manner;meanwhile,SAB-TAT-LIP significantly inhibited the migration and invasion of HSF. At the same time,SAB-TAT-LIP could block the cell cycle at G0/G1 phase after intervention for 48 h,P<0.01 as compared with the blank control group. Conclusively,our experimental data quantitatively demonstrate that SAB-TAT-LIP has significant inhibitory effect on cells proliferation,invasion and migration,with blocking effect on G0/G1 phase. This may offer a promising therapeutic strategy for transdermal delivery in prevention and treatment of HS.

Application of nanodrug carriers in the prevention and treatment of infection around orthopedic prosthesis / 生物医学工程学杂志

Despite the continuous improvement in perioperative use of antibiotics and aseptic techniques, the incidence of infection continues to rise as the need for surgery increasing and brings great challenges to orthopedic surgery. The rough or porous structure of the prosthesis provides an excellent place for bacterial adhesion, proliferation and biofilm formation, which is the main cause of infection. Traditional antibiotic therapy and surgical debridement are difficult to determine whether the infected focus have been removed completely and whether the infection will recur. In recent years, nanotechnology has shown obvious advantages in biomaterials and drug delivery. Nano drug carriers can effectively achieve local antimicrobial therapy, prevent surgical infection by local sustained drug release or intelligent controlled drug release under specific stimuli, and reduce the toxic side effects of drugs. The unique advantages of nanotechnology provide new ideas and options for the prevention and treatment of periprosthetic infection. At present, the application of nano-technology in the prevention and treatment of infection can be divided into the addition of nano-drug-loaded materials to prosthesis materials, the construction of drug-loaded nano-coatings on the surface of prosthesis, the perfusable nano-antimicrobial drug carriers, and the stimulation-responsive drug controlled release system. This article reviews the methods of infection prevention and treatment in orthopaedic surgery, especially the research status of nanotechnology in the prevention and treatment of periprosthetic infection.

Immune response and biochemistry of calves immunized with rMSP1a ( Anaplasma marginale) using carbon nanotubes as carrier molecules / Resposta imunológica e bioquímica de bezerros imunizados com rMSP1 a (Anaplasma marginale) utilizando nanotubos de carbono como moléculas carreadoras

Abstract Vaccination against Anaplasma marginale has been considered an important control strategy for bovine anaplasmosis. Recently, mice immunized with rMSP1 a linked to carbon nanotubes (MWNT) showed significant immune responses, generating a new possibility for use of an inactivated vaccine. The objective of this study was to investigate the cellular and humoral responses in calves immunized with MWNT+rMSP1a , associated with inactivated vaccine of A. marginale produced in vitro, and evaluate the toxic effects of the MWNT on renal and hepatic function. rMSP1a was covalently linked to MWNT. Inactivated vaccine (AmUFMG2) was produced by cultivating A. marginale in IDE8 cells. Twenty-four Holstein calves were divided (four groups) and immunized subcutaneously with PBS and non-carboxylated MWNT (control, G1), AmUFMG2 (G2), MWNT+rMSP1a (G3), and AmUFMG2 with MWNT+rMSP1a (G4). Blood samples were collected for total leukocyte counts, biochemical profiling and evaluation of the cellular and humoral response. Immunization with MWNT+rMSP1a induced increase in the total number of leukocytes, NK cells, in the lymphocyte populations and higher levels of antibodies compared to calves immunized only with AmUFMG2. Furthermore, MWNT did not induce changes in the biochemical profile. These data indicate that MWNT+rMSP1a were able to induce the immune responses more efficiently than AmUFMG2 alone, without generating toxicity.

Resumo Vacinação contra Anaplasma marginale tem sido considerada uma importante estratégia de controle da anaplasmose bovina. Recentemente, camundongos imunizados com rMSP1a funcionalizada à nanotubos de carbono (MWNT) apresentaram resposta imune significante, gerando nova possibilidade para o uso da vacina inativada. O objetivo desse estudo foi investigar a resposta celular e humoral em bezerros imunizados com MWNT+rMSP1a, associado com a vacina inativada de A. marginale produzida in vitro, e avaliar os efeitos tóxicos dos MWNT nas funções hepática e renal. rMSP1 a foi ligada covalentemente aos MWNT. Vacina inativada (AmUFMG2) foi produzida através do cultivo de A. marginale em células IDE8. Vinte e quatro bezerros Holandeses foram divididos (quatro grupos) e imunizados subcutaneamente com: PBS e MWNT não-carboxilados (controle, G1), AmUFMG2 (G2), MWNT+rMSP1 a (G3), e AmUFMG2 com MWNT+rMSP1a (G4). Amostras de sangue foram coletadas para contagem de leucócitos, perfil bioquímico e avaliação da resposta celular e humoral. Imunização com MWNT+rMSP1a induziu aumento dos leucócitos totais, células NK, na população de linfócitos e altos níveis de anticorpos comparado com animais imunizados apenas com AmUFMG2. Além disso, MWNT não induziu alterações no perfil bioquímico. Esses dados indicam que MWNT+rMSP1a foram capazes de induzir eficientemente a resposta imune comparado com AmUFMG2 sozinho, sem gerar toxicidade.

Improved stability and oral bioavailability of Ganneng dropping pills following transforming lignans of herpetospermum caudigerum into nanosuspensions / 中国天然药物

The present study was designed to improve storage stability and oral bioavailability of Ganneng dropping pills (GNDP) by transforming lignans of Herpetospermum caudigerum (HL) composed of herpetrione (HPE) and herpetin (HPN) into nanosuspension (HL-NS), the main active ingredient of GNDP, HL-NS was prepared by high pressure homogenization and lyophilized to transform into solid nanoparticles (HL nanoparticles), and then the formulated HL nanoparticles were perfused into matrix to obtain NS-GNDP by melting method. For a period of 3 months, the content uniformity, storage stability and pharmacokinetics test in vivo of NS-GNDP were evaluated and compared with regular GNDP at room temperature. The results demonstrated that uniformity of dosage units of NS-GNDP was acceptable according to the criteria of Chinese Pharmacopoeia 2015J. Physical stability of NS-GNDP was investigated systemically using photon correlation spectroscopy (PCS), zeta potential measurement, and scanning electron microscopy (SEM). There was a slight increase in particles and PI of HL-NS re-dispersed from NS-GNDP after storage for 3 months, compared with new formulated NS-GNDP, which indicated a good redispersibility of the NS-GNDP containing HL-NS after storage. Besides, chemical stability of NS-GNDP was studied and the results revealed that HPE and HPN degradation was less when compared with that of GNDP, providing more than 99% of drug residue after storage for 3 months. In the dissolution test in vitro, NS-GNDP remarkably exhibited an increased dissolution velocity compared with GNDP and no distinct dissolution difference existed within 3 months. The pharmacokinetic study showed that HPE and HPN in NS-GNDP exhibited a significant increase in AUC, C and decrease in T when compared with regular GNDP. These results indicated that NS-GNDP possessed superiority with improved storage stability and increased dissolution rate and oral bioavailability.

Formulation development and evaluation of gastroretentive floating beads with Brucea javanica oil using ionotropic gelation technology / 中国天然药物

In the present study, a gastric retention floating system for Brucea javanica oil, composed of alginate and carrageenan, was prepared using ionotropic gelation. Parameters for floatability, drug load, encapsulation efficiency, bead morphology, in vitro release, and in vivo gastric retention were evaluated. The optimized formulation via Box-Behnken design consisted of 1.7% alginate (W/V), 1.02% carrageenan (W/V), 1.4% CaCO (W/V), and a gelling bath of pH 0.8. The alginate-carrageenan-Brucea javanica oil beads had a porous structure and exhibited up to 24 h of in vitro floatability with a load capacity of 45%-55% and an encapsulation efficiency of 70%-80%. A 6-h sustained release was observed in vitro. The beads had a prolonged gastric retention (> 60% at 6 h) in fasted rats, compared to non-floating beads (15% at 6 h), as measured by gamma scintigraphy with single-photon emission tomography/computed tomography (SPET/CT). In conclusion, the alginate-carrageenan-Brucea javanica oil system showed enhanced oil encapsulation efficiency, excellent floating and gastric retention abilities, and a favorable release behavior.