Versatile redox-sensitive pullulan nanoparticles for enhanced liver targeting and efficient cancer therapy

Nanotechnological Approaches to Enhance the Potential of α-Lipoic Acid for Application in the Clinic

α-lipoic acid is a naturally occurring compound with potent antioxidant properties that helps protect cells and tissues from oxidative stress. Its incorporation into nanoplatforms can affect factors like bioavailability, stability, reactivity, and targeted delivery. Nanoformulations of α-lipoic acid can significantly enhance its solubility and absorption, making it more bioavailable. While α-lipoic acid can be prone to degradation in its free form, encapsulation within nanoparticles ensures its stability over time, and its release in a controlled and sustained manner to the targeted tissues and cells. In addition, α-lipoic acid can be combined with other compounds, such as other antioxidants, drugs, or nanomaterials, to create synergistic effects that enhance their overall therapeutic benefits or hinder their potential cytotoxicity. This review outlines the advantages and drawbacks associated with the use of α-lipoic acid, as well as various nanotechnological approaches employed to enhance its therapeutic effectiveness, whether alone or in combination with other bioactive agents. Furthermore, it describes the engineering of α-lipoic acid to produce poly(α-lipoic acid) nanoparticles, which hold promise as an effective drug delivery system.

Preparation, In Vitro Characterization, and Evaluation of Polymeric pH-Responsive Hydrogels for Controlled Drug Release

The purpose of the current research is to formulate a smart drug delivery system for solubility enhancement and sustained release of hydrophobic drugs. Drug solubility-related challenges constitute a significant concern for formulation scientists. To address this issue, a recent study focused on developing PEG-g-poly(MAA) copolymeric nanogels to enhance the solubility of olmesartan, a poorly soluble drug. The researchers employed a free radical polymerization technique to formulate these nanogels. Nine formulations were formulated. The newly formulated nanogels underwent comprehensive tests, including physicochemical assessments, dissolution studies, solubility evaluations, toxicity investigations, and stability examinations. Fourier transform infrared (FTIR) investigations confirmed the successful encapsulation of olmesartan within the nanogels, while thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) studies verified their thermal stability. Scanning electron microscopy (SEM) images revealed the presence of pores on the surface of the nanogels, facilitating water penetration and promoting rapid drug release. Moreover, powder X-ray diffraction (PXRD) studies indicated that the prepared nanogels exhibited an amorphous structure. The nanogel carrier system led to a significant enhancement in olmesartan's solubility, achieving a remarkable 12.3-fold increase at pH 1.2 and 13.29-fold rise in phosphate buffer of pH 6.8 (NGP3). Significant swelling was observed at pH 6.8 compared to pH 1.2. Moreover, the formulated nexus is nontoxic and biocompatible and depicts considerable potential for delivery of drugs and protein as well as heat-sensitive active moieties.

Recent advances of novel targeted drug delivery systems based on natural medicine monomers against hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the most prevalent type of liver cancer, is often diagnosed at an advanced stage. Surgical interventions are often ineffective, leading HCC patients to rely on systemic chemotherapy. Unfortunately, commonly used chemotherapeutic drugs have limited efficacy and can adversely affect vital organs, causing significant physical and psychological distress for patients. Natural medicine monomers (NMMs) have shown promising efficacy and safety profiles in HCC treatment, garnering attention from researchers. In recent years, the development of novel targeted drug delivery systems (TDDS) combining NMMs with nanocarriers has emerged. These TDDS aim to concentrate drugs effectively in HCC cells by manipulating the characteristics of nanomedicines, leveraging receptor and ligand interactions, and utilizing endogenous stimulatory responses to promote specific nanomedicines distribution. This comprehensive review presents recent research on TDDS for HCC treatment using NMMs from three perspectives: passive TDDS, active TDDS, and stimuli-responsive drug delivery systems (SDDS). It consolidates the current state of research on TDDS for HCC treatment with NMMs and highlights the potential of these innovative approaches in improving treatment outcomes. Moreover, the review also identifies research gaps in the related fields to provide references for future targeted therapy research in HCC.

Review of the Application of Dual Drug Delivery Nanotheranostic Agents in the Diagnosis and Treatment of Liver Cancer

Liver cancer has high incidence and mortality rates and its treatment generally requires the use of a combination treatment strategy. Therefore, the early detection and diagnosis of liver cancer is crucial to achieving the best treatment effect. In addition, it is imperative to explore multimodal combination therapy for liver cancer treatment and the synergistic effect of two liver cancer treatment drugs while preventing drug resistance and drug side effects to maximize the achievable therapeutic effect. Gold nanoparticles are used widely in applications related to optical imaging, CT imaging, MRI imaging, biomarkers, targeted drug therapy, etc., and serve as an advanced platform for integrated application in the nano-diagnosis and treatment of diseases. Dual-drug-delivery nano-diagnostic and therapeutic agents have drawn great interest in current times. Therefore, the present report aims to review the effectiveness of dual-drug-delivery nano-diagnostic and therapeutic agents in the field of anti-tumor therapy from the particular perspective of liver cancer diagnosis and treatment.

Recent developments in natural biopolymer based drug delivery systems

Targeted delivery of drug molecules to diseased sites is a great challenge in pharmaceutical and biomedical sciences. Fabrication of drug delivery systems (DDS) to target and/or diagnose sick cells is an effective means to achieve good therapeutic results along with a minimal toxicological impact on healthy cells. Biopolymers are becoming an important class of materials owing to their biodegradability, good compatibility, non-toxicity, non-immunogenicity, and long blood circulation time and high drug loading ratio for both macros as well as micro-sized drug molecules. This review summarizes the recent trends in biopolymer-based DDS, forecasting their broad future clinical applications. Cellulose chitosan, starch, silk fibroins, collagen, albumin, gelatin, alginate, agar, proteins and peptides have shown potential applications in DDS. A range of synthetic techniques have been reported to design the DDS and are discussed in the current study which is being successfully employed in ocular, dental, transdermal and intranasal delivery systems. Different formulations of DDS are also overviewed in this review article along with synthesis techniques employed for designing the DDS. The possibility of these biopolymer applications points to a new route for creating unique DDS with enhanced therapeutic qualities for scaling up creative formulations up to the clinical level.

Nanodrug delivery systems for metabolic chronic liver diseases: advances and perspectives

Nanomedicines are revolutionizing healthcare as recently demonstrated by the Pfizer/BioNTech and Moderna COVID-2019 vaccines, with billions of doses administered worldwide in a safe manner. Nonalcoholic fatty liver disease is the most common noncommunicable chronic liver disease, posing a major growing challenge to global public health. However, due to unmet diagnostic and therapeutic needs, there is great interest in the development of novel translational approaches. Nanoparticle-based approaches offer novel opportunities for efficient and specific drug delivery to liver cells, as a step toward precision medicines. In this review, the authors highlight recent advances in nanomedicines for the generation of novel diagnostic and therapeutic tools for nonalcoholic fatty liver disease and related liver diseases.

Engineering Transferrin-Decorated Pullulan-Based Prodrug Nanoparticles for Redox Responsive Paclitaxel Delivery to Metastatic Lung Cancer Cells

Paclitaxel (PTX) remains a cornerstone in the treatment of locally advanced and metastatic lung cancer. To improve its therapeutic indices against lung cancer, novel redox-sensitive pullulan/PTX-based prodrug NPs (PULL-SS-PTX NPs) were accomplished, which were further surface-decorated with transferrin (TF), a cancer cell-targeting ligand, to afford TF-PULL-SS-PTX NPs. These prodrug NPs (drug content, >37% and average size, 134-163 nm) rapidly dismantled their self-assembled architecture upon exposure to simulated reducing conditions, causing a triggered drug release as compared to the control scaffold (PULL-CC-PTX NPs). These scaffolds also evidenced outstanding colloidal stability, cellular uptake efficiency, and discriminating cytotoxicity between the cancer and healthy cells. Intravenously delivered redox-sensitive NPs exhibited improved tumor-suppressing properties as compared to the control nanovesicles (PULL-CC-PTX NPs) in a B16-F10 melanoma lung metastasis mice model. The targeting efficiency and associated augmented anticancer potentials of TF-PULL-SS-PTX NPs relative to TF-free redox-responsive NPs and Taxol intravenous injection were also established on the transferrin receptor (TFR) overexpressed Lewis lung carcinoma (LLC-luc) cell-bearing mice model. Moreover, the TF-functionalized scaffold displayed a reduced systemic toxicity compared to that of Taxol intravenous injection. Overall, the proposed TF-decorated prodrug NPs could be a promising nanomedicine for intracellular PTX delivery against metastatic lung cancer.

Tumor Microenvironment-Activated Hydrogel Platform with Programmed Release Property Evokes a Cascade-Amplified Immune Response against Tumor Growth, Metastasis and Recurrence

In situ tumor vaccines (ITV) have been recognized as a promising antitumor strategy since they contain the entire tumor-specific antigens, avoiding tumor cells from evading immune surveillance due to antigen loss. However, the therapeutic benefits of ITV are limited by obstacles such as insufficient antigen loading, inadequate immune system activation, and immunosuppressive tumor microenvironments (TME). Herein, a tumor microenvironment-activated hydrogel platform (TED-Gel) with programmed drug release property is constructed for cascaded amplification of the anti-tumor immune response elicited by ITV. Both doxorubicin (Dox) and cytosine-phosphate-guanosine oligodeoxynucleotides (CpG) are released first, in which Dox induces immunogenic tumor cell death causing additional tumor antigen release and leading the dying primary tumor cells into autologous tumor vaccine, and the released CpG promotes antigen presenting cell activation. Subsequently, the decomposed scaffold materials in conjunction with CpG, turn the anti-inflammatory M2-like macrophages into the M1 type, reversing the immunosuppressive TME. With decomposition of the TED-Gel, large amounts of macromolecule anti-PD-L1 antibodies are liberated, reinvigorating the exhausted effector T cells. In vivo studies demonstrate that TED-Gel significantly inhibits the primary, distant and rechallenged tumor growth. Overall, the simple and powerful TED-Gel provides an alternative strategy for the future development of tumor vaccines with broad application.

Stimuli-responsive crosslinked nanomedicine for cancer treatment

Nanomedicines are attractive paradigms to deliver drugs, contrast agents, immunomodulators, and gene editors for cancer therapy and diagnosis. However, the currently developed nanomedicine suffers from poor serum stability, premature drug release, and lack of responsiveness. Crosslinking strategy can be utilized to overcome these shortcomings by employing stimuli-responsive chemical bonds to tightly hold the nanostructure and releasing the payloads spatiotemporally in a highly controlled manner. In this Review, we summarize the recently ingenious design of the stimuli-responsive crosslinked nanomedicines (SCN) in the field of cancer treatment and their advances in circumventing the drawbacks of the conventional drug delivery system. We classify the SCNs into three categories based on the crosslinking strategies, including built-in, on-surface, and inter-particle crosslinking nanomedicines. Thanks to the stimuli-responsive crosslinkages, SCNs are capable of keeping robust stability during systemic circulation. They also respond to the particular tumoral conditions to experience a series of dynamic changes, such as the changes in size, surface charge, targeting moieties, integrity, and imaging signals. These characteristics allow them to efficiently overcome different biological barriers and substantially improve the drug delivery efficiency, tumor-targeting ability, and imaging sensitivities. With the examples discussed, we envision that our perspectives can inspire more attempts to engineer intelligent nanomedicine to achieve effective cancer therapy and diagnosis.

Light- and Redox-Responsive Block Copolymers of mPEG-SS-ONBMA as a Smart Drug Delivery Carrier for Cancer Therapy

The development of stimuli-responsive polymeric micelles for targeted drug delivery has attracted much research interest in improving therapeutic outcomes. This study designs copolymers responsive to ultraviolet (UV) light and glutathione (GSH). A disulfide linkage is positioned between a hydrophilic poly(ethylene glycol) monomethyl ether (mPEG) and a hydrophobic o-nitrobenzyl methacrylate (ONBMA) to yield amphiphilic copolymers termed mPEG-SS-pONBMA. Three copolymers with different ONBMA lengths are synthesized and formulated into micelles. An increase in particle size and a decrease in critical micelle concentration go together with increasing ONBMA lengths. The ONB cleavage from mPEG-SS-pONBMA-formed micelles results in the transformation of hydrophobic cores into hydrophilic ones, accelerating drug release from the micelles. Obvious changes in morphology and molecular weight of micelles upon combinational treatments account for the dual-stimuli responsive property. Enhancement of a cell-killing effect is clearly observed in doxorubicin (DOX)-loaded micelles containing disulfide bonds compared with those containing dicarbon bonds upon UV light irradiation. Collectedly, the dual-stimuli-responsive mPEG-SS-pONBMA micelle is a better drug delivery carrier than the single-stimuli-responsive mPEG-CC-pONBMA micelle. After HT1080 cells were treated with the DOX-loaded micelles, the high expression levels of RIP-1 and MLKL indicate that the mechanism involved in cell death is mainly via the DOX-induced necroptosis pathway.

Hyaluronic acid-modified redox-sensitive hybrid nanocomplex loading with siRNA for non-small-cell lung carcinoma therapy

A novel hyaluronic acid (HA)-modified hybrid nanocomplex HA-SeSe-COOH/siR-93C@PAMAM, which could efficiently deliver siRNA into tumor cells via a redox-mediated intracellular disassembly, was constructed for enhanced antitumor efficacy. Thereinto, siR-93C (siRNA) and positive PAMAM were firstly mixed into the electrostatic nano-intermediate, and then diselenide bond (-SeSe-)-modified HA was coved to shield excessive positive charges. This hybrid nanocomplex displayed uniform dynamic sizes, high stability, controlled zeta potential and narrow PDI distribution. Moreover, the -SeSe- linkage displayed GSH/ROS dual responsive properties, improving intracellular trafficking of siRNA. In vitro assays in A549 cell line presented that HA-SeSe-COOH/siR-93C@PAMAM has low cytotoxicity, rapid lysosomal escape and significant transfection efficiency; besides, an efficient proliferation inhibition ability and enhanced apoptosis. Furthermore, in animal studies, this negative-surfaced hybrid nanocomplex showed a prolonged circulation in blood and improved inhibition of tumor growth. All these results verified our hypothesis in this study that diselenide bonds-modified HA could promote not only stability and safety of nanoparticles in vivo but also intracellular behavior of siRNA via redox-dual sensitive properties; furthermore, this hybrid nanocomplex provided a visible potential approach for siRNA delivery in the antitumor field.

Nanomedicine in Hepatocellular Carcinoma: A New Frontier in Targeted Cancer Treatment

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death and is associated with a dismal median survival of 2-9 months. The fundamental limitations and ineffectiveness of current HCC treatments have led to the development of a vast range of nanotechnologies with the goal of improving the safety and efficacy of treatment for HCC. Although remarkable success has been achieved in nanomedicine research, there are unique considerations such as molecular heterogeneity and concomitant liver dysfunction that complicate the translation of nanotheranostics in HCC. This review highlights the progress, challenges, and targeting opportunities in HCC nanomedicine based on the growing literature in recent years.

In Vivo Biodistribution, Clearance, and Biocompatibility of Multiple Carbon Dots Containing Nanoparticles for Biomedical Application

Current research on the use of carbon dots for various biological systems mainly focuses on the single carbon dots, while particles that contain multiple carbon dots have scarcely been investigated. Here, we assessed multiple carbon dots-crosslinked polyethyleneimine nanoparticles (CDs@PEI) for their in vivo biodistribution, clearance, biocompatibility, and cellular uptake. The in vivo studies demonstrate three unique features of the CDs@PEI nanoparticles: (1) the nanoparticles possess tumor-targeting ability with steady and prolonged retention time in the tumor region. (2) The nanoparticles show hepatobiliary excretion and are clear from the intestine in feces. (3) The nanoparticles have much better biocompatibility than the polyethyleneimine passivated single carbon dots (PEI-CD). We also found that pegylated CDs@PEI nanoparticles can be effectively taken up by the cells, which the confocal laser scanning microscope can image under different excitation wavelengths (at 405, 488, and 800 nm). These prior studies provide invaluable information and new opportunities for this new type of intrinsic photoluminescence nanoparticles in carbon dot-based biomedical applications.

The use of nanotechnology to combat liver cancer: Progress and perspectives

Liver cancer is one of the most common cancers worldwide and is also one of the most difficult cancers to treat, resulting in almost one million deaths per year, and the danger of this cancer is compounded when the tumor is nonresectable. Hepatocellular carcinoma (HCC) is the most common type of liver cancer and has the third highest mortality rate worldwide. Considering the morbid statistics surrounding this cancer it is a popular research topic to target for better therapy practices. This review summarizes the role of nanotechnology in these endeavors. Nanoparticles (NPs) are a very broad class of material and many different kinds have been used to potentially combat liver cancer. Gold, silver, platinum, metal oxide, calcium, and selenium NPs as well as less common materials are all inorganic NPs that have been used as a therapeutic, carrier, or imaging agent in drug delivery systems (DDS) and these efforts are described. Carbon-based NPs, including polymeric, polysaccharide, and lipid NPs as well as carbon dots, have also been widely studied for this purpose and the role they play in DDS for the treatment of liver cancer is illustrated in this review. The multifunctional nature of many NPs described herein, allows these systems to display high anticancer activity in vitro and in vivo and highlights the advantage of and need for combinatorial therapy in treating this difficult cancer. These works are summarized, and future directions are presented for this promising field.

Advances in siRNA delivery strategies for the treatment of MDR cancer

RNA interference (RNAi) represents a promising therapeutic method that uses siRNA for cancer treatment. Although the RNAi technique has been increasingly used for clinical trials, systemic siRNA delivery into targeted cells is still challenging. The barriers impeding siRNA therapeutics delivery and impacting the treatment outcome must overcome with negligible systemic toxicity for a desirable and successful delivery of siRNA to MDR cancer cells. Nano delivery strategies have been investigated for nanocarrier functionalization, cancer immunotherapy and cancer targeting. Lipid nanoparticles (LNPs), dynamic polyconjugates (DPC™), GalNAc-siRNA conjugates, exosome and RBC systems have shown potential for efficient delivery of siRNA to cancer cells. Delivery of siRNA to tumor cells, immune cells to regulate T cell functions for immunotherapy are promising approaches.

Enhanced cytotoxicity of a redox-sensitive hyaluronic acid-based nanomedicine toward different oncocytes via various internalization mechanisms

Receptor-mediated active targeting and tumor microenvironment responsive systems from polymeric micelles have been studied for rapid cellular internalization and triggered drug release. Previously we have constructed redox-responsive polymeric micelles composed of vitamin E succinate conjugated hyaluronic acid (HA-ss-TOS), which are able to actively target CD44 proteins and quickly release loaded drugs upon exposure to high levels of glutathione (GSH) in tumor cells. In the present study, we found that despite different cellular internalization mechanisms, micelles showed strong antineoplastic effects on 4T1 and B16F10 cells due to redox responsiveness. HA-ss-TOS-PTX micelles exhibited an excellent tumor targeting ability and prolonged retention time compared to Taxol in vivo. In addition, a superior antitumor effect was achieved compared to PTX-loaded insensitive micelles (HA-TOS-PTX) and Taxol. Our results revealed that PTX-loaded HA-ss-TOS micelles could enhance the antineoplastic efficacy of PTX for breast cancer and melanoma treatment and, thus, deserve further attention.

Folate Modified Long Circulating Nano-Emulsion as a Promising Approach for Improving the Efficiency of Chemotherapy Drugs in Cancer Treatment

PURPOSE

In order to improve the therapeutic efficiency of the chemotherapeutic drug paclitaxel in tumors, a folate-based Paclitaxel nanoemulsion (FNEs) was developed for tumor targeted treatment.

METHODS

In this study, we designed a folate-targeted nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) based on the traditional nanoemulsion using the principle of long-circulation targeting receptor mediated. The nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) was fabricated using high-pressure homogenization with a microfluidizer.

RESULTS

The nanoemulsion (folate/PEG-DSPE/nanoemulsion, FNEs) can improve the delivery efficiency of nanocarriers at the tumor site by virtue of the high expression of folate receptors on the tumor surface. Malvern Nanoseries device and transmission electron microscopy (TEM) analyses showed that the nanoemulsions were spherical with an average diameter of 140 nm. The nanoemulsions can effectively carry paclitaxel (PTX) with an encapsulation rate of about 95%. And in vitro experiments have shown that it can efficiently increase the uptake of PTX in 4 T1 breast cancer cells and FNEs had a targeting capability hundredfold higher than that of PTX-loaded nanoemulsions (PTX-NEs) without folate. In vivo experiments have shown that the pharmacokinetic parameters of FNEs were better than those of other PTX groups and FNEs can significantly enhance circulation time in the body of the subcutaneously implanted 4 T1 breast cancer in mice, increase the accumulation of chemotherapy drugs at tumor sites and effectively inhibit tumor growth with lower system toxicity.

CONCLUSIONS

This study can effectively improve the therapeutic efficiency of chemotherapy drugs for tumors, and provide an useful reference for solving the problem of low efficacy of chemotherapy drugs in clinical treatment of tumors. Graphical Abstract Schematic representation of Folic acid/PEG-DSPE/nano-emulsion (FNEs) specifically target tumor cells and enhanced anti-tumor effects.

Multi-Stimuli-Responsive DOX Released from Magnetosome for Tumor Synergistic Theranostics

Background

To improve responses to tumor microenvironments for achieving a better therapeutic outcome in combination cancer therapy, poly(ε-caprolactone)-SS-poly(methacrylic acid) diblock copolymer (PCL-SS-PMAA) with a disulfide linkage between the hydrophobic and hydrophilic junctions was synthesized.

Materials and Methods

Repeating units of PCL and PMAA in PCL-SS-PMAA were controlled and formulated into polymersomes (PSPps). Truncated octahedral Fe₃O₄ nanoparticles (IONPs) were synthesized and encapsulated to produce IONPs-PSPps NPs and doxorubicin (DOX) was further loaded to produce IONPs-PSPps@DOX NPs for theranostic applications.

Results

IONPs-PSPps NPs remained a superparamagnetic property with a saturation magnetization value of 85 emu⋅g_Fe3O4 ^-1 and a relaxivity value of 180 mM^-1⋅s^-1. Upon exposure to an alternating magnetic field (AMF), IONPs-PSPps NPs increased temperature from 25°C to 54°C within 15 min. Among test groups, the cell apoptosis was greatest in the group exposed to IONPs-PSPps@DOX NPs with AMF and magnet assistance. In vivo T₂-weighted magnetic resonance images of A549 tumor-bearing mice also showed highest contrast and greatest tumor suppression in the tumor with AMF and magnet assistance.

Conclusion

IONPs-PSPps@DOX NPs are a potential theranostic agent having multifaceted applications involving magnetic targeting, MRI diagnosis, hyperthermia and chemotherapy.

Chemoresponsive polymer systems for selective molecular recognition of organic molecules in biological systems

Smart polymer materials that respond to a chemical stimulus are applied for the construction of biomedical devices and purification/separation systems. Small organic molecules are a particular type of stimulus. Their abnormal concentration indisputably indicates certain diseases. They are also hazardous environment contaminants. Polymer materials, which structure is selectively changed in the presence of a defined organic compound are promising in view of regulation of certain biomedical functions, as well as in view of chemical detectors construction. This review summarizes the state of the art in the self-assemblies of amphiphilic copolymers and polymer networks sensitive toward organic species, with an emphasis on the reports from the last decade. We focus on the relationship between the selectivity of introduced receptor moieties responsible for the change of material structure, the overall structure of material and its functionality.

Microbial Exopolysaccharides as Drug Carriers

Microbial exopolysaccharides are peculiar polymers that are produced by living organisms and protect them against environmental factors. These polymers are industrially recovered from the medium culture after performing a fermentative process. These materials are biocompatible and biodegradable, possessing specific and beneficial properties for biomedical drug delivery systems. They can have antitumor activity, they can produce hydrogels with different characteristics due to their molecular structure and functional groups, and they can even produce nanoparticles via a self-assembly phenomenon. This review studies the potential use of exopolysaccharides as carriers for drug delivery systems, covering their versatility and their vast possibilities to produce particles, fibers, scaffolds, hydrogels, and aerogels with different strategies and methodologies. Moreover, the main properties of exopolysaccharides are explained, providing information to achieve an adequate carrier selection depending on the final application.

Hepatic targeting of glycyrrhetinic acid via nanomicelles based on stearic acid-modified fenugreek gum

This study aimed to increase the solubility of glycyrrhetinic acid (GA) in water and enhance its liver-targeting ability using self-assembling nanomicelles (NMs) based on stearic acid-modified fenugreek gum (FG-C₁₈). The GA/FG-C₁₈ NMs were prepared by an ultrasonication dispersion method. The nanomicelles were spherical particles with a particle size of 198.61 ± 1.58 nm and a zeta potential of -30.12 ± 0.28 mV. The drug loading and encapsulation efficiency were 13.34 ± 0.24% and 80.07 ± 1.44%, respectively. The results of differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) indicated that GA was successfully encapsulated into the nanomicelles in a molecularly dispersed state. An in vitro release test showed that GA/FG-C₁₈ NMs possessed a slow drug release profile in PBS (pH 7.4) over 200 h. The cytotoxicity assay indicated that GA/FG-C₁₈ NMs showed much higher inhibitory efficacy in HepG2 cells than in MCF-7 cells. Tissue section studies indicated that the accumulation of DiR-loaded FG-C₁₈ nanomicelles in the liver of mice was higher than that of the DiR solution, and the fluorescence intensity decreased over time. GA/FG-C₁₈ NMs showed a larger area under the curve (AUC) and mean residence time (MRT) compared with free GA after intravenous administration in mice. The in vivo studies showed that GA mainly accumulated in the liver after encapsulation by FG-C₁₈ NMs, and the drug concentration was higher than that of free GA. These results suggested that FG-C₁₈ NMs could serve as a potential drug delivery system for targeting GA to liver tissue.

Construction of Ginsenoside Nanoparticles with pH/Reduction Dual Response for Enhancement of Their Cytotoxicity Toward HepG2 Cells

The aim of this study is to construct a pH- and reduction-responsive nanodrug delivery system to effectively deliver a ginsenoside (Rh₂) and enhance its cytotoxicity against human hepatocarcinoma cells (HepG2). Here, pullulan polysaccharide was grafted by urocanic acid and α-lipoic acid (α-LA) to obtain a copolymer, α-LA-conjugated N-urocanyl pullulan (LA-URPA), which was expected to have pH and redox dual response. Then, the copolymer LA-URPA was used to encapsulate ginsenoside Rh₂ to form Rh₂ nanoparticles (Rh₂ NPs). The results showed that Rh₂ NPs exhibited an average size of 119.87 nm with a uniform spherical morphology. Of note, Rh₂ NPs showed a high encapsulation efficiency of 86.00%. Moreover, Rh₂ NPs possessed excellent pH/reduction dual-responsive drug release under acidic conditions (pH 5.5) and glutathione (GSH) stimulation with a low drug leakage of 14.8% within 96 h. Furthermore, Rh₂ NPs with pH/reduction dual response had higher cytotoxicity than Rh₂ after incubation with HepG2 cells for 72 h, indicating that Rh₂ NPs had a longer circulation time. After the treatment with Rh₂ NPs, the excessive increase of reactive oxygen species and the decrease of superoxide dismutase, glutathione (GSH), and mitochondrial membrane potential suggested that the mitochondrial pathway mediated by oxidative stress played a role in this Rh₂ NP-induced apoptosis. In conclusion, this study provides a new strategy for improving the application of ginsenoside Rh₂ in the food and pharmaceutical fields.

PH and redox dual-responsive polymeric micelles with charge conversion for paclitaxel delivery

Here we demonstrate a type of pH and redox dual-responsive micelles, which were self-assembled in aqueous solution by an amphiphilic polymer, methoxypoly(ethylene glycol)-cystamine-poly(L-glutamic acid)-imidazole (mPEG-SS-PGA-IM). Considering tumor cells or tissues exhibiting low pH values and high glutathione (GSH) concentration, mPEG-SS-PGA-IM micelles possessed the charge conversion at pH of tumor tissues, which can facilitate cellular uptake of tumor cells. Furthermore, mPEG-SS-PGA-IM micelles can escape from endo/lysosomes based on the proton sponge effect, following degraded by higher concentration of GSH in cytoplasm. CLSM images of HCT116 cells indicated that mPEG-SS-PGA-IM micelles can escape from endo/lysosomes and enter cytoplasm. MTT assay showed that (paclitaxel) PTX-loaded mPEG-SS-PGA-IM micelles had higher cytotoxicity against HCT116 cells compared with PTX-loaded mPEG-PBLG and mPEG-SS-PBLG micelles. These results indicated that these mPEG-SS-PGA-IM micelles, as novel and effective pH- and redox-responsive nanocarriers, have great potential to both improve drug targeting efficiency while also enhancing the antitumor efficacy of PTX.

Pullulan for Advanced Sustainable Body- and Skin-Contact Applications

The present review had the aim of describing the methodologies of synthesis and properties of biobased pullulan, a microbial polysaccharide investigated in the last decade because of its interesting potentialities in several applications. After describing the implications of pullulan in nano-technology, biodegradation, compatibility with body and skin, and sustainability, the current applications of pullulan are described, with the aim of assessing the potentialities of this biopolymer in the biomedical, personal care, and cosmetic sector, especially in applications in contact with skin.

Recent advances of nanomedicines for liver cancer therapy

This review highlights recent advancements in nanomedicines for liver cancer therapy.

Enzyme-Catalytic Self-Triggered Release of Drugs from a Nanosystem for Efficient Delivery to Nuclei of Tumor Cells

Stimulus-responsive drug delivery nanosystems (DDSs) are of great significance in improving cancer therapy for intelligent control over drug release. However, among them, many DDSs are unable to realize rapid and sufficient drug release because most internal stimulants might be consumed during the release process. To address the plight, an abundant supply of stimulants is highly desirable. Herein, a core crosslinked pullulan-di-(4,1-hydroxybenzylene)diselenide nanosystem, which could generate abundant exogenous-stimulant reactive oxygen species (ROS) via tumor-specific NAD(P)H:quinone oxidoreductase-1 (NQO1) catalysis, was constructed by the encapsulation of β-lapachone. The enzyme-catalytic-generated ROS induced self-triggered cascade amplification release of loaded doxorubicin (DOX) in the tumor cells, thus achieving efficient delivery of DOX to the nuclei of tumor cells by breaking the diselenide bond of the nanosystem. As a result, the antitumor effect of this nanosystem was significantly improved in the HepG2 xenograft model. In general, this study offers a new paradigm for utilizing the interaction between the loaded agent and carrier in the tumor cells to obtain self-triggered drug release in the design of DDSs for enhanced cancer therapy.

Mild photothermal therapy potentiates anti-PD-L1 treatment for immunologically cold tumors via an all-in-one and all-in-control strategy

One of the main challenges for immune checkpoint blockade antibodies lies in malignancies with limited T-cell responses or immunologically “cold” tumors. Inspired by the capability of fever-like heat in inducing an immune-favorable tumor microenvironment, mild photothermal therapy (PTT) is proposed to sensitize tumors to immune checkpoint inhibition and turn “cold” tumors “hot.” Here we present a combined all-in-one and all-in-control strategy to realize a local symbiotic mild photothermal-assisted immunotherapy (SMPAI). We load both a near-infrared (NIR) photothermal agent IR820 and a programmed death-ligand 1 antibody (aPD-L1) into a lipid gel depot with a favorable property of thermally reversible gel-to-sol phase transition. Manually controlled NIR irradiation regulates the release of aPD-L1 and, more importantly, increases the recruitment of tumor-infiltrating lymphocytes and boosts T-cell activity against tumors. In vivo antitumor studies on 4T1 and B16F10 models demonstrate that SMPAI is an effective and promising strategy for treating “cold” tumors.

Active Cellular and Subcellular Targeting of Nanoparticles for Drug Delivery

Nanoparticle (NP)-mediated drug delivery (NMDD) for active targeting of diseases is a primary goal of nanomedicine. NPs have much to offer in overcoming the limitations of traditional drug delivery approaches, including off-target drug toxicity and the need for the administration of repetitive doses. In the last decade, one of the main foci in NMDD has been the realization of NP-mediated drug formulations for active targeted delivery to diseased tissues, with an emphasis on cellular and subcellular targeting. Advances on this front have included the intricate design of targeted NP-drug constructs to navigate through biological barriers, overcome multidrug resistance (MDR), decrease side effects, and improve overall drug efficacy. In this review, we survey advancements in NP-mediated drug targeting over the last five years, highlighting how various NP-drug constructs have been designed to achieve active targeted delivery and improved therapeutic outcomes for critical diseases including cancer, rheumatoid arthritis, and Alzheimer's disease. We conclude with a survey of the current clinical trial landscape for active targeted NP-drug delivery and how we envision this field will progress in the near future.

Polymeric nanoparticles as carrier for targeted and controlled delivery of anticancer agents

In recent decades, many novel methods by using nanoparticles (NPs) have been investigated for diagnosis, drug delivery and treatment of cancer. Accordingly, the potential of NPs as carriers is very significant for the delivery of anticancer drugs, because cancer treatment with NPs has led to the improvement of some of the drug delivery limitations such as low blood circulation time and bioavailability, lack of water solubility, drug adverse effect. In addition, the NPs protect drugs against enzymatic degradation and can lead to the targeted and/or controlled release of the drug. The present review focuses on the potential of NPs that can help the targeted and/or controlled delivery of anticancer agents for cancer therapy.

Enzymatically Disulfide-Crosslinked Chitosan/Hyaluronic Acid Layer-by-Layer Self-Assembled Microcapsules for Redox-Responsive Controlled Release of Protein

Disulfide-crosslinked hollow polyelectrolyte microcapsules composed of thiolated chitosan (CS-SH) and hyaluronic acid (HA-SH) were prepared by combining the layer-by-layer (LBL) technique and horseradish peroxidase (HRP)-mediated oxidative cross-linking reaction in mild conditions. FITC-dextran-doped CaCO₃ microspheres were used as template core and removed after LBL depositing CS-SH and HA-SH on the surface. The disulfide-crosslinked (CS/HA) microcapsules were readily fabricated by HRP-mediated oxidative coupling of the thiol groups in CS/HA shell layer in the presence of HRP (10 units/mL) and Tyramine hydrochloride (Tyr, 35 mmol/L). The kinetics of enzymatic disulfide-crosslinking reaction was investigated through the real-time monitoring of the consumption of thiol groups by UV absorption spectra. It found that the formation of disulfide linkages by the enzymatic thiol oxidation reaction showed a gradual acceleration. The disulfide-crosslinked CS/HA hydrogel were rapidly formed in gelation time between approximately 17 and 30 min, which were dependent on the concentrations of HRP and Tyr. The disulfide linkages endowed the microcapsule-enhanced physical stability and low permeability under physiological conditions and redox-responsive degradability in reducing environments. The structural stability of disulfide-crosslinked (CS/HA) microcapsules was visualized by confocal laser scanning microscopy in phosphate-buffered saline containing 5.0 mmol/L dithiothreitol (DTT) to evaluate the redox-responsive disassembly process. Redox-responsive controlled release of encapsulated FITC-dextran from the disulfide-crosslinked (CS/HA) microcapsules were obtained. The release profiles of FITC-dextran could be manipulated by controlling the shell thickness and the concentration of DTT. The conformational stability analyses and more than 94% esterase activity of released bovine serum albumin (BSA) from (CS/HA) microcapsules conformed that the structural integrity and bioactivity were well preserved during the encapsulation and release process. The microcapsules exhibited excellent cytocompatibility for HEK 293 cells up to a concentration of 1.0 mg/mL. The microcapsules efficiently delivered loaded FITC-BSA into HeLa cells and released the protein in the reducing cytosol. This study proposed a novel approach for producing disulfide-crosslinked microcarriers for intracellular delivery and redox-responsive controlled release of protein.

Galactosylated chitosan triptolide nanoparticles for overcoming hepatocellular carcinoma: Enhanced therapeutic efficacy, low toxicity, and validated network regulatory mechanisms

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths worldwide. Current therapies present significant limitations. Triptolide (TP) is highly effective against multiple cancers including HCC. However, high toxicity, low water solubility, and unknown therapeutic targets limit its clinical application. Herein, we designed galactosylated-chitosan-TP-nanoparticles (GC-TP-NPs) with high drug loading capacities for targeted delivery to HCC. In addition to a sustained release pattern, an efficient asialoglycoprotein receptor mediated cellular uptake in vitro, and high liver tumor accumulation in vivo, GC-TP-NPs showed lower systemic and male reproductive toxicities than free TP. Importantly, GC-TP-NPs retained the anti-cancer activities of the free TP, exerting the same pro-apoptotic and anti-proliferative effects on HCC cells in vitro, and displayed higher efficacies in reducing tumor sizes in vivo. Further investigation revealed that GC-TP-NPs induced cancer cell apoptosis via blocking TNF/NF-κB/BCL2 signaling. Collectively, GC-TP-NP represents a promising candidate in halting liver cancer progression while minimizing systemic toxicity.

A dual-targeting reconstituted high density lipoprotein leveraging the synergy of sorafenib and antimiRNA21 for enhanced hepatocellular carcinoma therapy

Sorafenib (So) is a multi-target kinase inhibitor extensively used in clinic for hepatocellular carcinoma therapy. It demonstrated strong inhibition both in tumor proliferation and tumor angiogenesis, while hampered by associated cutaneous side-effect and drug resistance. The knockdown of miR-21 with antisense oligonucleotides (antimiRNA21) was regarded as an efficient strategy for increasing tumor sensibility to chemotherapy, which could be employed to appreciate the efficacy of So. Herein, we successfully formulated a dual-targeting delivery system for enhanced hepatocellular carcinoma therapy by encapsulating So and antimiRNA21 in RGD pentapeptide-modified reconstituted high-density lipoprotein (RGD-rHDL/So/antimiRNA21). The RGD and apolipoprotein A-I (ApoA-I) on nanoparticles (NPs) could drive the system simultaneously to tumor neovascular and parenchyma by binding to the overexpressed ανβ3-integrin and SR-B1 receptors, achieving precise delivery of therapeutics to maximize the efficacy. A series in vitro and in vivo experiments revealed that co-delivery of So and antimiRNA21 by RGD-rHDL significantly strengthened the anti-tumor and anti-angiogenic effect of So with negligible toxicity towards major organs, reversed drug-resistance and was capable of remodeling tumor environments. The constructed RGD-rHDL/So/antimiRNA21 with improved efficacy and excellent tumor targeting ability provided new idea for chemo-gene combined therapy in hepatocellular carcinoma.

STATEMENT OF SIGNIFICANCE

Sorafenib (So) is a multi-target kinase inhibitor which was approved by FDA as first-line drug for hepatocellular carcinoma (HCC) therapy. However, long term application of So in clinic was hampered by serious dermal toxicity and drug resistance. Although numerous researchers were devoted to finding alternatives or therapies as combination treatments with So to reach more desired therapeutic efficacy, the therapeutic options were still limited. The present study prepares RGD pentapeptide decorated biomimic reconstituted high-density lipoprotein (rHDL) loaded with So and antimiRNA21 (RGD-rHDL/So/antimiRNA21) for enhanced HCC therapy. The RGD-rHDL/So/antimiRNA21 NPs offer an effective platform for anti-tumor and anti-angiogenesis therapy in HCC and provide new approach to reverse drug-resistance of So for feasible clinical application.