Stable cerasomes for simultaneous drug delivery and magnetic resonance imaging

Bile salt integrated cerasomes: A potential nanocarrier for enhancement of the oral bioavailability of idarubicin hydrochloride

Cerasomes are a modified form of liposomes containing both inorganic and organic parts and due to their strong polyorganosiloxane surface have remarkably high morphological stability and provide easier functionalization compared with conventional liposomes. To investigate the potential of these nanocarriers for oral delivery, bile salt integrated cerasomes (named bilocerasomes) encapsulating idarubicin hydrochloride (IDA) were prepared and characterized. The optimum formulation showed excellent stability in the simulated gastrointestinal fluids as well as under storage conditions. The oral pharmacokinetics of the IDA solution, empty nanocarrier + drug solution, and IDA-loaded bilocerasome were evaluated. The nanoformulation significantly increased the area under the drug concentration-time curve and the mean residence time (∼14.3- and 9-fold, respectively). The results obtained from cell uptake and chylomicron flow blocking approach revealed that bilocerasomes are absorbed into the intestinal cells via a clathrin/caveolin-independent endocytosis pathway and transported to the systemic circulation extensively via the intestinal lymphatic vessels. Considering the high stability of the prepared bilocerasome, noticeable participation of lymphatic transport in its systemic absorption and marked enhancement in the oral absorption of IDA, bilocerasomes can be introduced as a capable carrier for improving the oral bioavailability of drugs, particularly those that hepatic first-pass metabolism seriously limits their oral absorption.

A Moexitecan Magnetic Liposomal Strategy for Ferroptosis-Enhanced Chemotherapy

Moexitecan (Mex) is a novel camptothecin derivative that retains the potent antitumor properties of camptothecin drugs and has improved hydrophilicity to enhance biocompatibility in vitro. However, single-drug therapy still has limitations. In this study, magnetic liposomes loaded with both moexitecan and superparamagnetic iron oxide nanoparticles (SPIO) have been fabricated by a film hydration and filtration method, which is abbreviated as Mex@MLipo. By using liposomes as drug carriers, Mex can be delivered specifically to the target site, resulting in improved therapeutic efficacy and reduced toxicity. Morphology characterization results show that Mex@MLipo has a mean diameter of 180-200 nm with a round morphology. The loading efficiencies of Mex and SPIO are 65.86% and 76.86%, respectively. Cell toxicity, in vitro cell uptake, and in vivo fluorescence imaging experiments showed that Mex@MLipo was the most effective in killing HT-29 cells compared with HepG-2 and PC-3 cells, due to its ability to combine chemotherapy and induce ferroptosis, resulting in a strong anti-tumor effect. Thus, this study developed an innovative nanoscale drug delivery system that paves the way for clinical applications of moexitecan.

Cerasome Versus Liposome: A Comparative Pharmacokinetic Analysis Following Intravenous Administration into Rats

Background

Cerasomes, due to their external siloxane network, demonstrate markedly higher physicochemical stability and, therefore, easier handling and storage than liposomes.

Objectives

The main objective of this study was to compare the pharmacokinetics (PK) of cerasome and liposome following intravenous administration. The PK of PEGylated and non-PEGylated cerasomes was also compared to see whether the presence of a hydrophilic siloxane network on the surface of cerasomes can play the role of polyethylene glycol (PEG) in increasing the blood circulation of these vesicles.

Methods

Silver sulfide (Ag2S) quantum dots (Qds)-loaded PEGylated and non-PEGylated cerasomes and PEGylated liposomes were fabricated and thoroughly characterized in terms of particle size, polydispersity index, zeta potential, entrapment efficiency, and in vitro stability. For pharmacokinetic evaluation, the free Qds and the selected formulations were intravenously injected into rats, and blood samples were collected for up to 72 hours. Pharmacokinetic parameters were calculated by the non-compartmental method.

Results

Both cerasomal and liposomal carriers significantly improved the PK of Qds. For example, the elimination half-life (t1/2) and the area under the plasma concentration-time curve from time 0 to time infinity (AUC0-∞) for the free Qds were 4.39 h and 8.01 µg/mL*h and for cerasomal and liposomal formulations were 28.82 versus 26.95 h and 73.25 versus 62.02 µg/mL*h, respectively. However, compared to each other, the plasma concentration-time profiles of PEGylated cerasomes and liposomes displayed similar patterns, and the statistical comparison of their pharmacokinetic parameters did not show any significant difference between the two types of carriers. For PEGylated cerasomes, t1/2 and AUC0-∞ values were respectively 1.6 and 3.3 times greater than the classic cerasome, indicating that despite the presence of a hydrophilic siloxane network, the incorporation of PEG is necessary to reduce the clearance of cerasomes.

Conclusions

The comparable PK of PEGylated cerasomes and liposomes, along with the higher physicochemical stability of cerasomes, can be considered an important advantage for the clinical application of cerasomes. Additionally, the easy surface functionalizing ability of cerasomes confers a dual advantage over liposomes. The study findings also showed that the presence of a hydrophilic siloxane network on the surface of cerasomes alone is not enough to make them circulate long.

Medical and Dental Applications of Titania Nanoparticles: An Overview

Currently, titanium oxide (TiO₂) nanoparticles are successfully employed in human food, drugs, cosmetics, advanced medicine, and dentistry because of their non-cytotoxic, non-allergic, and bio-compatible nature when used in direct close contact with the human body. These NPs are the most versatile oxides as a result of their acceptable chemical stability, lower cost, strong oxidation properties, high refractive index, and enhanced aesthetics. These NPs are fabricated by conventional (physical and chemical) methods and the latest biological methods (biological, green, and biological derivatives), with their advantages and disadvantages in this epoch. The significance of TiO₂ NPs as a medical material includes drug delivery release, cancer therapy, orthopedic implants, biosensors, instruments, and devices, whereas their significance as a dental biomaterial involves dentifrices, oral antibacterial disinfectants, whitening agents, and adhesives. In addition, TiO₂ NPs play an important role in orthodontics (wires and brackets), endodontics (sealers and obturating materials), maxillofacial surgeries (implants and bone plates), prosthodontics (veneers, crowns, bridges, and acrylic resin dentures), and restorative dentistry (GIC and composites).

Advancing the Pharmaceutical Potential of Bioinorganic Hybrid Lipid-Based Assemblies

Bioinspired lipid assemblies that mimic the elaborate architecture of natural membranes have fascinated researchers for a long time. These lipid assemblies have gone from being just an imperative platform for biophysical research to a pharmaceutical delivery system for biomedical applications. Despite success, these organized nanosystems are often subject to the mechanical instability and limited theranostic capability without adding any inconvenient modifications. To reach their advanced pharmaceutical potential, various bioinorganic hybrid lipid-based assembles, which provide new opportunities to synergistically complement and improve therapeutic/diagnostic potential of existing lipid-based nanomedicine with distinct mechanisms containing inorganic embedded surfactants, have recently been developed.

Nanomaterial-involved neural stem cell research: Disease treatment, cell labeling, and growth regulation

Neural stem cells (NSCs) have been widely investigated for their potential in the treatment of various diseases and transplantation therapy. However, NSC growth regulation, labeling, and its application to disease diagnosis and treatment are outstanding challenges. Recently, nanomaterials have shown promise for various applications including genetic modification, imaging, and controlled drug release. Here we summarize the recent progress in the use of nanomaterials in combination with NSCs for disease treatment and diagnosis, cell labeling, and NSC growth regulation. The toxicity of nanomaterials to NSCs is also discussed.

Cerasomes and Bicelles: Hybrid Bilayered Nanostructures With Silica-Like Surface in Cancer Theranostics

Over years, theranostic nanoplatforms have provided a new avenue for the diagnosis and treatment of various cancer types. To this end, a myriad of nanocarriers such as polymeric micelles, liposomes, and inorganic nanoparticles (NPs) with distinct physiochemical and biological properties are routinely investigated for preclinical and clinical studies. So far, liposomes have received great attention for various biomedical applications, however, it still suffers from insufficient morphological stability. On the other hand, inorganic NPs depicting excellent therapeutic ability have failed to address biocompatibility issues. This has raised a serious concern about the clinical approval of multifunctional organic or inorganic-based theranostic agents. Recently, partially silica coated nanohybrids such as cerasomes and bicelles demonstrating both diagnostic and therapeutic ability in a single system, have drawn profound attention as a fascinating novel drug delivery system. Compared with traditional liposomal or inorganic-based nanoformulations, this new and highly stable nanocarriers integrates the functional attributes of biomimetic liposomes and silica NPs, therefore, synergize strengths and functions, or even surpass weaknesses of individual components. This review at its best enlightens the emerging concept of such partially silica coated nanohybrids, fabrication strategies, and theranostic opportunities to combat cancer and related diseases.

Target-specific delivery of oxaliplatin to HER2-positive gastric cancer cells in vivo using oxaliplatin-au-fe3o4-herceptin nanoparticles

Gastric cancer is the fourth most common malignancy globally. In order to decrease the dosage and side effects of conventional chemotherapy, and achieve improved benefits from molecular targeted therapy, novel drug delivery systems were developed in the present study. Oxaliplatin-Au-Fe₃O₄-Herceptin^® acts as a dual-functional nanoparticles (NPs) conjugate and possesses the capability of human epithelial growth factor receptor 2 (HER2) targeting and oxaliplatin delivery. The 8-20 nm Au-Fe₃O₄ were synthesized by decomposing iron pentacarbonyl on the surfaces of Au NPs in the presence of oleic acid and oleylamine. Following being coated with polyethylene glycol, the NPs possessed a ζ-potential of 13.8±1.6 mV and were demonstrated to exhibit no cytotoxicity when Fe concentration is <100 µg/ml via an MTS assay. Mass spectrometry analysis detected a peak at m/z 148,000, and Nuclear Magnetic Resonance indicated peaks at δ 3.51 (8.00H, s, 3-H), 2.97-3.02 (3.80H, t, 2-H) and 2.72-2.76 (3.72H, t, 1-H) following successful loading with Herceptin and oxaliplatin probes. A drug release assay via dialysis cassettes demonstrated that 25% of the oxaliplatin was released at pH 8.0, however >58% was released at pH 6.0 following 4 h incubation, indicating its pH-dependent release characteristic. The active targeting feature of oxaliplatin-Au-Fe₃O₄-Herceptin was verified in a subcutaneous xenograft mouse model containing SGC-7901 cells via detecting aggregated low intensity in T₂-weighted magnetic resonance imaging, which was further confirmed by immunohistochemistry. Therefore, oxaliplatin-Au-Fe₃O₄-Herceptin is a promising multifunctional platform for simultaneous magnetic traceable and HER2 targeted chemotherapy for gastric cancer.

Potential applications and human biosafety of nanomaterials used in nanomedicine

With the rapid development of nanotechnology, potential applications of nanomaterials in medicine have been widely researched in recent years. Nanomaterials themselves can be used as image agents or therapeutic drugs, and for drug and gene delivery, biological devices, nanoelectronic biosensors or molecular nanotechnology. As the composition, morphology, chemical properties, implant sites as well as potential applications become more and more complex, human biosafety of nanomaterials for clinical use has become a major concern. If nanoparticles accumulate in the human body or interact with the body molecules or chemical components, health risks may also occur. Accordingly, the unique chemical and physical properties, potential applications in medical fields, as well as human biosafety in clinical trials are reviewed in this study. Finally, this article tries to give some suggestions for future work in nanomedicine research. Copyright © 2017 John Wiley & Sons, Ltd.

Efficient induction of apoptosis in cancer cells by paclitaxel-loaded selenium nanoparticles

Aim: To develop selenium nanoparticles (SeNPs)-based delivery systems for paclitaxel (PTX) and assess their antiproliferative efficacy against cancer cells in vitro with potential mechanistic insight. Methods: Pluronic F-127 stabilized SeNPs were prepared and characterized. Effects of PTX-loaded SeNPs on lung (A549), breast (MCF7), cervical (HeLa) and colon (HT29) cancer cells were studied by viability assay complemented with flow-cytometric analyses of cell cycle, apoptosis, mitochondrial membrane potential, intracellular reactive oxygen species and caspase activity. Results: PTX-loaded SeNPs demonstrated significant antiproliferative activity against cancer cells. Cell cycle analyses of PTX-SeNPs treated cells established G2/M phase arrest in a dose-dependent manner leading to apoptosis. Further investigation revealed disruption of mitochondrial membrane potential orchestrated with induction of reactive oxygen species leading to the activation of caspases, key players of apoptotic cell death. Conclusion: Efficient induction of apoptosis in various cancer cells by PTX-loaded SeNPs, with appropriate future studies, might lead to potential anticancer strategies.

A Conjugate of Pentamethine Cyanine and 18F as a Positron Emission Tomography/Near-Infrared Fluorescence Probe for Multimodality Tumor Imaging

The novel synthesis of a dual-modality, pentamethine cyanine (Cy5) fluorescent, ¹⁸F positron emission tomography (PET) imaging probe is reported. The probe shows a large extinction coefficient and large quantum yield in the biologically transparent, near-infrared window (650–900 nm) for in vivo fluorescent imaging. This fluorophore bears the isotope, ¹⁸F, giving a ¹⁸F-PET/near-infrared fluorescent (NIRF), bi-modal imaging probe, that combines the long-term stability of NIRF and the unlimited penetration depth of PET imaging. The bi-modal probe is labeled with ¹⁸F in a quick, one-step reaction, which is important in working with the rapid decay of ¹⁸F. The bi-modal probe bears a free carboxyl group, highlighting a PET/NIRF synthon that can be conjugated onto many advanced biomolecules for biomarker-specific in vivo dual-modal PET/NIR tumor imaging, confocal histology, and utility in multi-fluorophore, fluorescence-guided surgery. Its potential in vivo biocompatibility is explored in a quick proof-of-principal in vivo study. The dye is delivered to A549 xenograft flank-tumors to generate PET and NIRF signals at the tumor site. The tumor distribution is confirmed in ex vivo gamma counting and imaging. Pentamethine cyanine (Cy5) has the ability to preferentially accumulate in tumor xenografts. We substitute the PET/NIRF probe for Cy5, and explore this phenomenon.

Chitosan coated gold nanorod chelating gadolinium for MRI-visible photothermal therapy of cancer

The multifunctional nanoparticles synthesized via nonsolvent counterion complexation method are applied for in vivo MR imaging and photothermal therapy of cancer.

Upconversion nanoparticle-mediated photodynamic therapy induces THP-1 macrophage apoptosis via ROS bursts and activation of the mitochondrial caspase pathway

Atherosclerosis (AS) is the most vital cardiovascular disease, which poses a great threat to human health. Macrophages play an important role in the progression of AS. Photodynamic therapy (PDT) has emerged as a useful therapeutic modality not only in the treatment of cancer but also in the treatment of AS. The purpose of this study was to determine the molecular mechanisms underlying the activity of PDT, using mesoporous-silica-coated upconversion fluorescent nanoparticles encapsulating chlorin e6 (UCNPs-Ce6) in the induction of apoptosis in THP-1 macrophages. Here, we investigated the ability of UCNPs-Ce6-mediated PDT to induce THP-1 macrophage apoptosis by facilitating the induction of reactive oxygen species (ROS) and regulation of mitochondrial permeability transition pore (MPTP) to depolarize mitochondrial membrane potential (MMP). Both Bax translocation and the release of cytochrome C were examined using immunofluorescence and Western blotting. Our results indicated that the levels of ROS were significantly increased in the PDT group, resulting in both MPTP opening and MMP depolarization, which led to apoptosis. In addition, immunofluorescence and Western blotting revealed that PDT induced both Bax translocation and the release of cytochrome C, as well as upregulation of cleaved caspase-9, cleaved caspase-3, and cleaved poly(ADP-ribose) polymerase. Therefore, we demonstrated that UCNPs-Ce6-mediated PDT induces apoptosis in THP-1 macrophages via ROS bursts. The proapoptotic factor Bax subsequently translocates from the cytosol to the mitochondria, resulting in the MPTP opening and cytochrome C release. This study demonstrated the great potential of UCNPs-Ce6-mediated PDT in the treatment of AS.