Redox responsive xylan-SS-curcumin prodrug nanoparticles for dual drug delivery in cancer therapy

Better together: nanoscale co-delivery systems of therapeutic agents for high-performance cancer therapy

Combination therapies can enhance the sensitivity of cancer to drugs, lower drug doses, and reduce side effects in cancer treatment. However, differences in the physicochemical properties and pharmacokinetics of different therapeutic agents limit their application. To avoid the above dilemma and achieve accurate control of the synergetic ratio, a nanoscale co-delivery system (NCDS) has emerged as a prospective tool for combined therapy in cancer treatment, which is increasingly being used to co-load different therapeutic agents. In this study, we have summarized the mechanisms of therapeutic agents in combination for cancer therapy, nanoscale carriers for co-delivery, drug-loading strategies, and controlled/targeted co-delivery systems, aiming to give a general picture of these powerful approaches for future NCDS research studies.

Lignocellulosic-biomolecules conjugated systems: green-engineered complexes modified by covalent linkers

Lignocellulosic biomass represents an abundant and eco-friendly material widely explored in recent years. The main lignocellulosic fractions include cellulose, hemicellulose, and lignin. Nonetheless, the heterogeneity and complexity of these components pose challenges in achieving the desired properties. Conversely, their attractive functional groups can covalently link with other biomolecules, facilitating the creation and enhancement of material properties. Lignocellulosic molecules can form different linkages with other biomolecules through classic and modern methods. Bioconjugation has emerged as a suitable alternative to create new nuances, empowering the linkage between lignocellulosic materials and biomolecules through linkers. These conjugates (lignocellulosic-linkers-biomolecules) attract attention from stakeholders in medicine, chemistry, biology, and agriculture. The plural formations of these biocomplexes highlight the significance of these arrangements. Therefore, this review provides an overview of the progress of lignocellulosic-biomolecule complexes and discusses different types of covalent bioconjugated systems, considering the formation of linkers, applicability, toxicity, and future challenges.

Gd/hafnium oxide@gold@chitosan core-shell nanoparticles as a platform for multimodal theranostics in oncology research

In the current study, we synthesized thiolated chitosan-stabilized gold-coated, gadolinium-doped hafnium oxide nanoparticles (CAuGH NPs) with the capability of acting as a multifunctional system to deliver anticancer drug doxorubicin (DOX), to enhance radiosensitization by ROS generation, and to provide magnetic resonance (MR) imaging contrast for biomedical applications.

Stimuli-responsive (nano)architectures for phytochemical delivery in cancer therapy

The use of phytochemicals for purpose of cancer therapy has been accelerated due to resistance of tumor cells to conventional chemotherapy drugs and therefore, monotherapy does not cause significant improvement in the prognosis and survival of patients. Therefore, administration of natural products alone or in combination with chemotherapy drugs due to various mechanisms of action has been suggested. However, cancer therapy using phytochemicals requires more attention because of poor bioavailability of compounds and lack of specific accumulation at tumor site. Hence, nanocarriers for specific delivery of phytochemicals in tumor therapy has been suggested. The pharmacokinetic profile of natural products and their therapeutic indices can be improved. The nanocarriers can improve potential of natural products in crossing over BBB and also, promote internalization in cancer cells through endocytosis. Moreover, (nano)platforms can deliver both natural and synthetic anti-cancer drugs in combination cancer therapy. The surface functionalization of nanostructures with ligands improves ability in internalization in tumor cells and improving cytotoxicity of natural compounds. Interestingly, stimuli-responsive nanostructures that respond to endogenous and exogenous stimuli have been employed for delivery of natural compounds in cancer therapy. The decrease in pH in tumor microenvironment causes degradation of bonds in nanostructures to release cargo and when changes in GSH levels occur, it also mediates drug release from nanocarriers. Moreover, enzymes in the tumor microenvironment such as MMP-2 can mediate drug release from nanocarriers and more progresses in targeted drug delivery obtained by application of nanoparticles that are responsive to exogenous stimulus including light.

Encapsulation of Polyphenolic Compounds Based on Hemicelluloses to Enhance Treatment of Inflammatory Bowel Diseases and Colorectal Cancer

Inflammatory bowel diseases (IBD) and colorectal cancer (CRC) are difficult to cure, and available treatment is associated with troubling side effects. In addition, current therapies have limited efficacy and are characterized by high costs, and a large segment of the IBD and CRC patients are refractive to the treatment. Moreover, presently used anti-IBD therapies in the clinics are primarily aimed on the symptomatic control. That is why new agents with therapeutic potential against IBD and CRC are required. Currently, polyphenols have received great attention in the pharmaceutical industry and in medicine due to their health-promoting properties. They may exert anti-inflammatory, anti-oxidative, and anti-cancer activity, via inhibiting production of pro-inflammatory cytokines and enzymes or factors associated with carcinogenesis (e.g., matrix metalloproteinases, vascular endothelial growth factor), suggesting they may have therapeutic potential against IBD and CRC. However, their use is limited under both processing conditions or gastrointestinal interactions, reducing their stability and hence their bioaccessibility and bioavailability. Therefore, there is a need for more effective carriers that could be used for encapsulation of polyphenolic compounds. In recent years, natural polysaccharides have been proposed for creating carriers used in the synthesis of polyphenol encapsulates. Among these, hemicelluloses are particularly noteworthy, being characterized by good biocompatibility, biodegradation, low immunogenicity, and pro-health activity. They may also demonstrate synergy with the polyphenol payload. This review discusses the utility and potential of hemicellulose-based encapsulations of polyphenols as support for treatment of IBD and CRC.

A carrier-free nano-drug assembled via π-π stacking interaction for the treatment of osteoarthritis

Osteoarthritis (OA) is considered to be the most common joint disorder. Exogenous drug intervention is one of the effective means for OA treatment. Clinical applications of numerous drugs are restricted owing to the short retention as well as rapid clearance in the joint cavity. A wide variety of carrier-based nanodrugs have been developed, but additional carriers may bring unexpected side effects or even toxicity. Herein, by exploiting the spontaneous fluorescence of Curcumin, we designed a new carrier-free self-assembly nanomedicine Curcumin (Cur)/icariin (ICA) nanoparticles with adjustable particle size, which is composed of two small-molecule natural drugs assembled via π-π stacking interaction. Experimental results revealed that Cur/ICA NPs endowed with little cytotoxicity, high cellular uptake and sustained drug release, could inhibit secretion of inflammatory cytokines and reduce cartilage degeneration. Moreover, both the in vitro and in vivo experiments showed the NPs exerted superior synergism effects in anti-inflammatory and cartilage protection than either Cur or ICA alone, and self-monitored its retention by autofluorescence. Thus, the new self-assembly nano-drug combining Cur and ICA represents a new strategy for the treatment of osteoarthritis.

Dextran/eudragit S-100 based redox sensitive nanoparticles for colorectal cancer therapy

Herein, we present disulfide crosslinked dextran/eudragit S-100 nanoparticles (DEEU NPs) (≈55 nm) for colorectal cancer treatment. These redox environment sensitive DEEU NPs are synthesized by simple oxidation of thiolated polymers in air. This approach allows avoiding the use of any additional chemical crosslinker. These DEEU NPs have high encapsulation efficiency for the doxorubicin (DOX) model drug (≈95%). The prepared DEEU NPs are redox sensitive owing to disulfide units and exhibit ≈80% DOX release in the reducing environment of GSH. Additionally, DOX-DEEU NPs display enhanced cytotoxicity for HCT116 cancer cells as compared to free DOX. Annexin V staining results also support the higher anticancer efficiency of DOX-DEEU NPs via induction of apoptosis. In vivo biodistribution results demonstrate that DEEU NPs can remain in the colon region for up to 24 hours. These results indicate that DEEU NPs can act as a promising platform for colorectal cancer treatment.

Poly(pro-curcumin) Materials Exhibit Dual Release Rates and Prolonged Antioxidant Activity as Thin Films and Self-Assembled Particles

Curcumin is a natural polyphenol that exhibits remarkable antioxidant and anti-inflammatory activities; however, its clinical application is limited in part by its physiological instability. Here, we report the synthesis of curcumin-derived polyesters that release curcumin upon hydrolytic degradation to improve curcumin stability and solubility in physiological conditions. Curcumin was incorporated in the polymer backbone by a one-pot condensation polymerization in the presence of sebacoyl chloride and polyethylene glycol (PEG, M_n = 1 kDa). The thermal and mechanical properties, surface wettability, self-assembly behavior, and drug-release kinetics all depend sensitively on the mole percentage of curcumin incorporated in these statistical copolymers. Curcumin release was triggered by the hydrolysis of phenolic esters on the polymer backbone, which was confirmed using a PEGylated curcumin model compound, which represented a putative repeating unit within the polymer. The release rate of curcumin was controlled by the hydrophilicity of the polymers. Burst release (2 days) and extended release (>8 weeks) can be achieved from the same polymer depending on curcumin content in the copolymer. The materials can quench free radicals for at least 8 weeks and protect primary neurons from oxidative stress in vitro. Further, these copolymer materials could be processed into both thin films and self-assembled particles, depending on the solvent-based casting conditions. Finally, we envision that these materials may have potential for neural tissue engineering application, where antioxidant release can mitigate oxidative stress and the inflammatory response following neural injury.

Novel pH-sensitive nanoparticles based on prodrug strategy to delivery All-Trans Retinoic Acid for breast cancer

Developing chemotherapy with nanoparticle-based prodrugs provides promising strategies for improving the safety and delivery of anti-cancer drugs therapeutics and effective cancer treatment. Herein, we developed a pH-sensitive prodrug delivery system (All-Trans-Retinoic Acid (ATRA) grafted poly (β-amino esters) (PBAE) copolymers, ATRA-g-PBAE) for delivery of ATRA with some physicochemical and biological properties. The in vitro release of ATRA-g-PBAE prodrug nanoparticles (PNPs) was sustained-release and pH-sensitive. The cytotoxicity and uptake of different preparations in vitro were evaluated on MCF-7 cells at pH 7.4 and 5.5. The carrier PBAE had no cytotoxicity, and ATRA-g-PBAE PNPs could significantly inhibit cell growth at pH 5.5. MCF-7 cells treated with Cy5.5 grafted PBAE (Cy5.5-PBAE) showed stronger fluorescence signals at pH 5.5. Meanwhile, ATRA-g-PBAE PNPs entered the cell via a clathrin-mediated endocytic pathway. Subsequently, PBAE protonation facilitated the escape of PNPs from the lysosome and released the drug. ATRA-g-PBAE seems promising as a novel pH-sensitive prodrug to overcome the limitations of ATRA for breast cancer therapy.

Redox-Responsive Drug Delivery Systems: A Chemical Perspective

With the widespread global impact of cancer on humans and the extensive side effects associated with current cancer treatments, a novel, effective, and safe treatment is needed. Redox-responsive drug delivery systems (DDSs) have emerged as a potential cancer treatment with minimal side effects and enhanced site-specific targeted delivery. This paper explores the physiological and biochemical nature of tumors that allow for redox-responsive drug delivery systems and reviews recent advances in the chemical composition and design of such systems. The five main redox-responsive chemical entities that are the focus of this paper are disulfide bonds, diselenide bonds, succinimide-thioether linkages, tetrasulfide bonds, and platin conjugates. Moreover, as disulfide bonds are the most commonly used entities, the review explored disulfide-containing liposomes, polymeric micelles, and nanogels. While various systems have been devised, further research is needed to advance redox-responsive drug delivery systems for cancer treatment clinical applications.

5-fluorouracil and curcumin with pectin coating as a treatment regimen for titanium dioxide with dimethylhydrazine-induced colon cancer model

Colorectal cancer was inducted in Wister rats using titanium dioxide nanoparticles (TiO₂NPs) and dimethylhydrazine (DMH) and treatment using 5-fluorouracil (5-FU) and curcumin (CUR), individually and following a synergistic approach. Compatibility studies are evaluated by using FT-IR spectra analysis, and Vero cell lines as well as HCT-116 cell lines are used for evaluating the synergistic approach. It was then followed by induction of colorectal cancer in rats for 70 days and treatment using 5-FU and CUR with pectin coating (individually and in combination) for 28 days. The reports state that 5-FU and CUR combination was found to be compatible. The synergistic effect was evaluated for1:1, 1:2, 1:4, and 2:1 ratio of 5-FU:CUR, where 1:4 ratio shows a CI₅₀ value of 0.853, selected further for the animal studies. The 1:4 ratio of 5-FU and CUR (50:200) shows to be effective for the treatment of colorectal cancer within 28 days, proven using histopathology report, bodyweight analysis, and hematological reports. 5-FU and CUR (1:4) ratio with pectin coating was proven effective for the treatment of colorectal cancer induced by TiO₂NPs with DMH and was found to produce a synergistic effect.

Synthesis, Characterization and Bioactivity Evaluation of a Novel Nano Bagasse Xylan/Andrographolide Grafted and Esterified Derivative

In the in-depth research that has been conducted on nanometer biomaterials, how to use the biomass resources with high activity and low toxicity to prepare nanomaterials for biomedical applications has attracted much attention. To realize efficient and comprehensive utilization of biomass, bagasse xylan/andrographolide (BX/AD) was ued as a raw material and glycyrrhetinic acid (GA) as an esterification agent to synthesize bagasse xylan/andrographolide esterified derivative (GA-BX/AD). Then, the bagasse xylan/andrographolide grafted and esterified derivative (GA-BX/AD-g-IA) was synthesized by the graft crosslinking reactions using itaconic acid (IA) as graft monomer. The better synthesis conditions were optimized by single factor experiments, the degree of esterification substitution (DS) was 0.43, and the grafting rate (G) of the product reached 42%. The structure and properties of the product were characterized by FTIR, XRD, DTG, SEM, and ¹H NMR. The results showed that the product morphology was significantly changed, and the nanoparticles were spherical with a particle size of about 100 nm. The anti-cancer activity of the product was measured. The molecular docking simulations revealed that the product had good docking activity with human glucocorticoid protein (6CFN) with a binding free energy of 14.38 kcal/mol. The MTT assay showed that the product had a strong inhibitory effect on the growth of human liver cancer cells (BEL-7407) and gastric cancer cells (MGC80-3), with inhibition ratio of 38.41 ± 5.32% and 32.69 ± 4.87%. Therefore, this nanomaterial is expected to be applied to the development and utilization of drug carriers and functional materials.

Synthesis and Anticancer Activity of Bagasse Xylan/Resveratrol Graft-Esterified Composite Nanoderivative

Biomass materials are high-quality raw materials for the preparation of natural, green and highly active functional materials due to their rich active groups, wide sources and low toxicity. Bagasse xylan (BX) and resveratrol (Res) were used as raw materials to introduce ethylene glycol dimethacrylate (EGDMA) via grafting reaction to obtain the intermediate product BX/Res-g-EGDMA. The intermediate was esterified with 3-carboxyphenylboronic acid (3-CBA) to obtain the target product 3-CBA-BX/Res-g-EGDMA. The BX/Res-composite-modified nanoderivative with antitumor activity was synthesized with the nanoprecipitation method. The effects of the reaction conditions on the grafting rate (G) of BX/Res-g-EGDMA and the degree of substitution (DS) of 3-CBA-BX/Res-g-EGDMA were investigated using single-factor experiments. The results showed that under the optimized process conditions, G and DS reached 142.44% and 0.485, respectively. The product was characterized with FTIR, XRD, TG-FTC, ¹H NMR and SEM, and its anticancer activity was simulated and tested. The results showed that 3-CBA-BX/Res-g-EGDMA had a spherical structure with an average particle size of about 100 nm and that its crystalline structure and thermal stability were different from those of the raw materials. In addition, 3-CBA-BX/Res-g-EGDMA showed the best docking activity with 2HE7 with a binding free energy of −6.3 kJ/mol. The inhibition rate of 3-CBA-BX/Res-g-EGDMA on MGC80-3 (gastric cancer cells) reached 36.71 ± 4.93%, which was 18 times higher than that of BX. Therefore, this material could be a potential candidate for biomedical applications.

GA&HA-Modified Liposomes for Co-Delivery of Aprepitant and Curcumin to Inhibit Drug-Resistance and Metastasis of Hepatocellular Carcinoma

Background

Tumor microenvironment (TME) plays a vital role in the development of hepatocellular carcinoma (HCC). Mounting evidence indicates that peripheral nerves could induce a shift from quiescent hepatic stellate cells (HSCs) to cancer-associated fibroblasts (CAFs) by secreting substance P (SP). The anti-tumor strategy by targeting “SP-HSCs-HCC” axis might be an effective therapy to inhibit tumor growth and metastasis.

Objective

In this study, we prepared novel liposomes (CUR-APR/HA&GA-LPs) modified with hyaluronic acid (HA) and glycyrrhetinic acid (GA) for co-delivery aprepitant (APR) and curcumin (CUR), in which APR was chosen to inhibit the activation of HSCs by blocking SP/neurokinin-1 receptor (NK-1R), and CUR was used to induce apoptosis of tumor cells.

Results

To mimic the TME, we established “SP+HSCs+HCC” co-cultured cell model in vitro. The results showed that CUR-APR/HA&GA-LPs could be taken up by CAFs and HCC simultaneously, and inhibit tumor cell migration. Meanwhile, the “SP+m-HSCs+HCC” co-implanted mice model was established to evaluate the anti-tumor effect in vivo. The results showed that CUR-APR/HA&GA-LPs could inhibit tumor proliferation and metastasis, and reduce extracellular matrix (ECM) deposition and tumor angiogenesis, indicating a superior anti-HCC effect.

Conclusion

Overall, the combination therapy based on HA&GA-LPs could be a potential nano-sized formulation for anti-HCC therapy.

Polysaccharide-Based Theranostic Systems for Combined Imaging and Cancer Therapy: Recent Advances and Challenges

Designing novel systems for efficient cancer treatment and improving the quality of life for patients is a prime requirement in the healthcare sector. In this regard, theranostics have recently emerged as a unique platform, which combines the benefits of both diagnosis and therapeutics delivery. Theranostics have the desired contrast agent and the drugs combined in a single carrier, thus providing the opportunity for real-time imaging to monitor the therapy results. This helps in reducing the hazards related to treatment overdose or underdose and gives the possibility of personalized therapy. Polysaccharides, as natural biomolecules, have been widely explored to develop theranostics, as they act as a matrix for simultaneously loading both contrast agents and drugs for their utility in drug delivery and imaging. Additionally, their remarkable physicochemical attributes (biodegradability, satisfactory safety profile, abundance, and diversity in functionality and charge) can be tuned via postmodification, which offers numerous possibilities to develop theranostics with desired characteristics. Hence, we provide an overview of recent advances in polysaccharide matrix-based theranostics for drug delivery combined with magnetic resonance imaging, computed tomography, positron emission tomography, single photon emission computed tomography, and ultrasound imaging. Herein, we also summarize the toxicity assessment of polysaccharides, associated contrast agents, and nanotoxicity along with the challenges and future research directions.

Preparation, physicochemical and pharmacological study of 10-hydroxycamptothecin solid dispersion with complexation agent - xylan-nonanoic acid amphiphilic conjugates

An amphiphilic conjugate of carboxymethyl xylan-nonanoic acid (CX-NA) was synthesized with molecular weight of 38.35 kDa, HLB value of 13.59, and critical micelle concentration of 23.17 μg/ml. CX-NA could efficiently encapsulate the model drug of 10-hydroxycamptothecin (HCPT). The drug loaded amphiphilic conjugate could self-assembled to micelles with an average diameter of 110 nm, zeta potential of -42.88 mV, and drug encapsulation efficiency of 79.8%. In vitro experiments confirmed that the drug-loaded micelles exhibited excellent stability and permeability in the intestinal environment. Transport pathway demonstrated that HCPT was uptake by cells through clathrin-mediated endocytosis. Intestinal in situ absorption study further confirmed CX-NA vehicle could enhance HPCT to transport across intestinal epithelial cells in colonic tissues. Furthermore, the formulation showed excellent anti-tumor activity in vitro and improved bioavailability of 3.4 times in vivo as comparing with free HCPT. These findings imply that this amphiphilic conjugate is a potential and promising vehicle for delivery anticancer drug.

A dual-responsive nanoplatform with feedback amplification improves antitumor efficacy of photodynamic therapy

A good photosensitizer (PS) delivery system could enhance the efficiency and reduce the side effects of anti-tumor photodynamic therapy (PDT) by improving accumulation in the tumor, uptake by tumor cells, and intracellular release of the PS. Thus, we rationally developed a multi-stimulus-responsive PS nanocarrier with a double-layered core-shell structure: mPEG-azo-hyaluronic acid-sulfide-Ce6 (PaHAsC). In PaHAsC, the mPEG coat provides protection before entering the hypoxic tumor microenvironment, where mPEG leaves to expose the HA layer. HA then targets overexpressed CD44 on tumor cells for enhanced internalization. Finally, GSH-mediated intracellular release of Ce6 augments ROS generation and O₂ consumption under light stimulation. This also aggravates hypoxia in tumor sites to accelerate mPEG removal, forming a positive feedback loop. Data show that PaHAsC dramatically improved the PDT efficacy of Ce6, eliminating most tumors and 80% of tumor-bearing mice survived. With a safe profile, PaHAsC has potential for further development and is a useful example of a PS delivery system.

Targeted Delivery Methods for Anticancer Drugs

Simple Summary

The current main technological strategies for the delivery of anticancer drugs are discussed herein. This comprehensive review may help researchers design suitable delivery systems.

Abstract

Several drug-delivery systems have been reported on and often successfully applied in cancer therapy. Cell-targeted delivery can reduce the overall toxicity of cytotoxic drugs and increase their effectiveness and selectivity. Besides traditional liposomal and micellar formulations, various nanocarrier systems have recently become the focus of developmental interest. This review discusses the preparation and targeting techniques as well as the properties of several liposome-, micelle-, solid-lipid nanoparticle-, dendrimer-, gold-, and magnetic-nanoparticle-based delivery systems. Approaches for targeted drug delivery and systems for drug release under a range of stimuli are also discussed.

Synergistic action of curcumin and cisplatin on spinel ferrite/hierarchical MCM-41 nanocomposite against MCF-7, HeLa and HCT 116 cancer cell line

Background

Platinum-based drugs are widely used in cancer therapy, but are known for toxic side effects and resistance. Combinational drug delivery represents an effective chemotherapeutic strategy, but often leads to an increased toxicity. Aim of this study is to test the co-delivery of cisplatin with natural antioxidants on hierarchial porous large surface area hexagonal nanocarriers for synergistic action.

Results

A series of structured mesoporous materials were impregnated with magnetic spinel ferrite (30% CuFe2O4) and then coated with curcumin (25% wt/wt). Mesosilicalite and MCM-41 with high curcumin release abilities were functionalized with cisplatin (5% wt/wt) for synergistic effect of combinational drugs. The cytotoxic efficiency of our nanocomposites was tested on cell viability of MCF7 (human breast cancer), human cervical cancer (HeLa), colorectal cancer (HCT116), and HFF (human foreskin fibroblasts) cell lines using the MTT cell viability assay. At a concentration of 0.1 mg/ml, CuFe2O4/mesosilicalite/curcumin/cisplatin resulted in 89.53% reduction in viability in MCF7, 94.03% in HeLa, 64% in HCT116 and 87% in HFF; whereas, CuFe2O4/MCM-41/curcumin/cisplatin resulted in 76% reduction in viability in MCF7, 64.46% in HeLa, 64% in HCT116 and 24% in HFF. The EC50 for CuFe2O4/mesosilicalite/curcumin/cisplatin was 81.23 µg/ml in MCF7, 47.55 µg/ml in HeLa, 48.96 µg/ml in HCT116 and 76.83 µg/ml in HFF. The EC50 for CuFe2O4/MCM-41/curcumin/cisplatin was 72.51 µg/ml in MCF7, 58.6 µg/ml in HeLa, 62.58 µg/ml in HCT116 and 154.2 µg/ml in HFF. Furthermore, cells treated with both nanocomposites had a high number of cleaved Caspase 3-positive cells suggesting that the reduction in cell viability was triggered by activating the apoptotic signaling pathway.

Conclusion

Our results show that CuFe2O4/MCM-41/curcumin/cisplatin is a better candidate for combinational drug therapy due to its lowest EC50 value and the wider difference in EC50 (a fold change) between cancerous and non-cancerous cell line.

Imaging application and radiosensitivity enhancement of pectin decorated multifunctional magnetic nanoparticles in cancer therapy

In this contribution, we report the fabrication of multifunctional nanoparticles with gold shell over an iron oxide nanoparticles (INPs) core. The fabricated system combines the magnetic property of INPs and the surface plasmon resonance of gold. The developed nanoparticles are coated with thiolated pectin (TPGINs), which provides stability to the nanoparticles dispersion and allows the loading of hydrophobic anticancer drugs. Curcumin (Cur) is used as the model drug and an encapsulation efficiency of approximately 80% in TPGINs is observed. Cytotoxicity study with HeLa cells shows that Cur-loaded TPGINs have better viability percent (~30%) than Cur alone (~40%) at a dose of 30 μg of TPGINs. Further, annexin V-PI assay demonstrated the enhanced anticancer activity of Cur-loaded TPGINs via induction of apoptosis. The use of TPGINs leads to a significant enhancement in generating reactive oxygen species (ROS) in HeLa cells through improved radiosensitization by gamma irradiation (0.5 Gy). TPGINs are further evaluated for imparting contrast in magnetic resonance imaging (MRI) with the r₂ relaxivity in the range of 11.06-13.94 s^-1 μg^-1 mL when measured at 7 Tesla. These experimental results indicate the potential of TPGINs for drug delivery and MR imaging.

Role of ACE2-Ang (1-7)-Mas axis in post-COVID-19 complications and its dietary modulation

Severe acute respiratory syndrome-coronavirus-2 (COVID-19) virus uses Angiotensin-Converting Enzyme 2 (ACE2) as a gateway for their entry into the human body. The ACE2 with cleaved products have emerged as major contributing factors to multiple physiological functions and pathogenic complications leading to the clinical consequences of the COVID-19 infection Decreased ACE2 expression restricts the viral entry into the human cells and reduces the viral load. COVID-19 infection reduces the ACE2 expression and induces post-COVID-19 complications like pneumonia and lung injury. The modulation of the ACE2-Ang (1–7)-Mas (AAM) axis is also being explored as a modality to treat post-COVID-19 complications. Evidence indicates that specific food components may modulate the AAM axis. The variations in the susceptibility to COVID-19 infection and the post-COVID its complications are being correlated with varied dietary habits. Some of the food substances have emerged to have supportive roles in treating post-COVID-19 complications and are being considered as adjuvants to the COVID-19 therapy. It is possible that some of their active ingredients may emerge as the direct treatment for the COVID-19.

Smart stimuli-responsive nanocarriers for the cancer therapy – nanomedicine

Nanomedicine is ongoing current research in the applications of nanotechnology for cancer therapy. Simply from a technology perspective, this field of research has an enormous broadening and success to date. Recently, nanomedicine has also made inroads in the treatment of cancer. Stimuli-responsive nanoparticles are an emerging field of research because its targeting capacity is of great interest in the treatment of cancer. The responsive nanoparticles are efficient in encountering different internal biological stimuli (acidic, pH, redox, and enzyme) and external stimuli (temperature, ultrasounds, magnetic field, and light), which are used as smart nanocarriers for delivery of the chemotherapeutic and imaging agents for cancer therapy. In-depth, the responsive nanocarrier that responds to the biological cues is of pronounced interest due to its capability to provide a controlled release profile at the tumor-specific site. The outlook of this review focuses on the stimuli-responsive nanocarrier drug delivery systems in sequence to address the biological challenges that need to be evaluated to overcome conventional cancer therapy.

Glutathione-responsive prodrug conjugates for image-guided combination in cancer therapy

Theranostic prodrug was highly desirable for precise diagnosis and anti-cancer therapy to decrease side effects. However, it is difficult to conjugate chemo-drug and molecular probe for combined therapy due to the complex pharmacokinetics of different molecules. Here, a novel anticancer theranostic prodrug (BTMP-SS-PTX) had been designed and synthesized by conjugating paclitaxel (PTX) with 2-(benzo[d]thiazol-2-yl)-4-methoxyphenol (BTMP) through a disulphide (-S-S-) linkage, which was redox-sensitive to the high concentration of glutathione in tumors. Upon activation with glutathione in weakly acid media, the BTMP-SS-PTX can be dissociated to release free PTX and visible BTMP, which realized the visual tracking of free drug. The cytotoxicity study demonstrated that soluble prodrug BTMP-SS-PTX displayed more outstanding anticancer activity in HepG2, MCF-7 and HeLa cells, lower toxicity to non-cancer cells (293 T) than free drugs. Furthermore, BTMP-SS-PTX was still able to induce apoptosis of HeLa cells and significantly inhibited tumor growth in HeLa-xenograft mouse model. On the basis of these findings, BTMP-SS-PTX could play a potential role in cancer diagnosis and therapy.

Curcumin nanoformulations to combat aging-related diseases

Aging increases the susceptibility to a diverse set of diseases and disorders, including neurodegeneration, cancer, diabetes, and arthritis. Natural compounds are currently being explored as alternative or complementary agents to treat or prevent aging-related malfunctions. Curcumin, a phytochemical isolated from the spice turmeric, has garnered great interest in recent years. With anti-oxidant, anti-inflammatory, anti-microbial, and other physiological activities, curcumin has great potential for health applications. However, the benefits of curcumin are restricted by its low bioavailability and stability in biological systems. Curcumin nanoformulations, or nano-curcumin, may overcome these limitations. This review discusses different forms of nano-curcumin that have been evaluated in vitro and in vivo to treat or prevent aging-associated health impairments. We describe current barriers for the routine use of curcumin nanoformulations in the clinic. Our review highlights outstanding questions and future work that is needed to ensure nano-curcumin is efficient and safe to lessen the burden of aging-related health problems.

A review of stimuli-responsive polymeric micelles for tumor-targeted delivery of curcumin

Despite a potential drug with multiple pharmacological activities, curcumin has disadvantages of the poor water solubility, rapid metabolism, low bioavailability, which considerably limit its clinical application. Currently, polymeric micelles (PMs) have gained widespread concern due to their advantageous physical and chemical properties, easy preparation, and biocompatibility. They can be used to improve drug solubility, prolong blood circulation time, and allow passive targeted drug delivery to tumor through enhanced penetration and retention effect. Moreover, studies focused on tumor microenvironment offer alternatives to design stimulus-responsive smart PMs based on low pH, high levels of glutathione, altered enzyme expression, increased reactive oxygen species production, and hypoxia. There are various external stimuli, such as light, ultrasound, and temperature. These endogenous/exogenous stimuli can be used for the research of intelligent micelles. Intelligent PMs can effectively load curcumin with improved solubility, and intelligently respond to release the drug at a controlled rate at targeted sites such as tumors to avoid early release, which markedly improves the bioavailability of curcumin. The present review is aimed to discuss and summarize recent developments in research of curcumin-loaded intelligent PMs based on endogenous and exogenous stimuli, and facilitates the development of novel delivery systems for future research.

Current Landscape in Organic Nanosized Materials Advances for Improved Management of Colorectal Cancer Patients

Globally, colorectal cancer (CRC) ranks as one of the most prevalent types of cancers at the moment, being the second cause of cancer-related deaths. The CRC chemotherapy backbone is represented by 5-fluorouracil, oxaliplatin, irinotecan, and their combinations, but their administration presents several serious disadvantages, such as poor bioavailability, lack of tumor specificity, and susceptibility to multidrug resistance. To address these limitations, nanomedicine has arisen as a powerful tool to improve current chemotherapy since nanosized carriers hold great promise in improving the stability and solubility of the drug payload and enhancing the active concentration of the drug that reaches the tumor tissue, increasing, therefore, the safety and efficacy of the treatment. In this context, the present review offers an overview of the most recent advances in the development of nanosized drug-delivery systems as smart therapeutic tools in CRC management and highlights the emerging need for improving the existing in vitro cancer models to reduce animal testing and increase the success of nanomedicine in clinical trials.

Co-Delivery of Curcumin and Capsaicin by Dual-Targeting Liposomes for Inhibition of aHSC-Induced Drug Resistance and Metastasis

Recent research studies have shown that the low survival rate of liver cancer is due to drug resistance and metastasis. In the tumor microenvironment (TME), activated hepatic stellate cells (aHSCs) have been proven to favor the development of liver cancer. Hence, the combination therapy dual-targeting aHSCs and tumor cells might be an effective strategy for treatment of liver cancer. In this study, the novel multifunctional liposomes (CAPS-CUR/GA&Gal-Lip) were prepared for co-delivery of curcumin (CUR) and capsaicin (CAPS), in which glycyrrhetinic acid (GA) and galactose (Gal) were chosen as targeting ligands to modify the liposomes (Lip) for dual-targeting liver cancer. To mimic TME, a novel HSCs+HepG2 (human hepatoma cell line) cocultured model was established for the antitumor effect in vitro. The results showed that, compared to HepG2 cells alone, the cocultured model promoted drug resistance and migration by upregulating the expression of P-glycoprotein (P-gp) and Vimentin, which were effectively inhibited by CAPS-CUR/GA&Gal-Lip. The efficacy of the in vivo antitumor was evaluated by three mice models: subcutaneous H22 (mouse hepatoma cell line) tumor-bearing mice, H22+m-HSC (mouse hepatic stellate cell) tumor-bearing mice, and orthotopic H22 cells-bearing mice. The results showed that CAPS-CUR/GA&Gal-Lip exhibited lesser extracellular matrix (ECM) deposition, lesser tumor angiogenesis, and superior antitumor effect compared with the no- and/or Gal-modified Lip, which was attributed to the simultaneous blocking of the activation of HSCs and inhibition of the metastasis of tumor cells. The dual-targeting method using Lip is thus a potential strategy for liver cancer treatment.

Natural products based nanoformulations for cancer treatment: Current evolution in Indian research

The use of medicinal plants is as ancient as human civilization. The development of phytochemistry and pharmacology facilitates the identification of natural bioactive compounds and their mechanisms of action, including against cancer. The efficacy and the safety of a bioactive compound depend on its optimal delivery to the target site. Most natural bioactive compounds (phenols, flavonoids, tannins, etc.) are unable to reach their target sites due to their low water solubility, less cellular absorption, and high molecular weight, leading to their failure into clinical translation. Therefore, many scientific studies are going on to overcome the drawbacks of natural products for clinical applications. Several studies in India, as well as worldwide, have proposed the development of natural products-based nanoformulations to increase their efficacy and safety profile for cancer therapy by improving the delivery of natural bioactive compounds to their target site. Therefore, we are trying to discuss the development of natural products-based nanoformulations in India to improve the efficacy and safety of natural bioactive compounds against cancer.

Co-delivery Systems of Multiple Drugs Using Nanotechnology for Future Cancer Therapy

Cancer treatments have improved significantly during the last decade but are not yet satisfactory. Combination therapy is often administered to improve efficacy and safety. Drug delivery systems can also improve efficacy and safety. To control the spatiotemporal distribution of drugs, nanotechnology involving liposomes, solid lipid nanoparticles, and polymeric micelles has been developed. Co-delivery systems of multiple drugs are a promising approach to combat cancer. Synergistic effects and reduced side effects are expected from the use of co-delivery systems. In this review, we summarize various co-delivery systems for multiple drugs, including small-molecule drugs, nucleic acids, genes, and proteins. Co-delivery of drugs with different properties is relatively difficult, but some researchers have succeeded in developing such co-delivery systems. Environment-responsive carrier designs can control the release of cargos. Although their preparation is more complicated than that of mono-delivery systems, co-delivery systems can simplify clinical procedures and improve patient QOL.

A Review of Lignocellulosic-Derived Nanoparticles for Drug Delivery Applications: Lignin Nanoparticles, Xylan Nanoparticles, and Cellulose Nanocrystals

Due to their biocompatibility, biodegradability, and non-toxicity, lignocellulosic-derived nanoparticles are very potential materials for drug carriers in drug delivery applications. There are three main lignocellulosic-derived nanoparticles discussed in this review. First, lignin nanoparticles (LNPs) are an amphiphilic nanoparticle which has versatile interactions toward hydrophilic or hydrophobic drugs. The synthesis methods of LNPs play an important role in this amphiphilic characteristic. Second, xylan nanoparticles (XNPs) are a hemicellulose-derived nanoparticle, where additional pretreatment is needed to obtain a high purity xylan before the synthesis of XNPs. This process is quite long and challenging, but XNPs have a lot of potential as a drug carrier due to their stronger interactions with various drugs. Third, cellulose nanocrystals (CNCs) are a widely exploited nanoparticle, especially in drug delivery applications. CNCs have low cytotoxicity, therefore they are suitable for use as a drug carrier. The research possibilities for these three nanoparticles are still wide and there is potential in drug delivery applications, especially for enhancing their characteristics with further surface modifications adjusted to the drugs.

Redox-sensitive nanoparticles based on xylan-lipoic acid conjugate for tumor targeted drug delivery of niclosamide in cancer therapy

In this study, novel redox-sensitive nanoparticles based on xylan-lipoic acid (Xyl-LA) conjugate were developed for tumor targeted delivery of niclosamide (Nic) in cancer therapy. The niclosamide loaded xylan-lipoic acid conjugate nanoparticles (Xyl-LA/Nic NPs) showed redox responsive behaviour in presence of reductive glutathione (GSH), which indicate their suitability for intracellular drug release. The obtained Xyl-LA/Nic NPs exhibited uniform particle size (196 ± 1.64 nm), high loading capacity (~28.6 wt %) and excellent blood compatibility. The anticancer activity of the Niclosamide and the Xyl-LA/Nic NPs against the colon carcinoma cell lines (HCT-15, Colo-320) were evaluated by MTT assay and the overall results indicate that the Xyl-LA/Nic NPs significantly enhanced the therapeutic efficiency of niclosamide in cancer therapy.

Overcoming Biological Barriers With Block Copolymers-Based Self-Assembled Nanocarriers. Recent Advances in Delivery of Anticancer Therapeutics

Cancer is one of the most common life-threatening illness and it is the world's second largest cause of death. Chemotherapeutic anticancer drugs have many disadvantages, which led to the need to develop novel strategies to overcome these shortcomings. Moreover, tumors are heterogenous in nature and there are various biological barriers that assist in treatment reisistance. In this sense, nanotechnology has provided new strategies for delivery of anticancer therapeutics. Recently, delivery platforms for overcoming biological barriers raised by tumor cells and tumor-bearing hosts have been reported. Among them, amphiphilic block copolymers (ABC)-based self-assembled nanocarriers have attracted researchers worldwide owing to their unique properties. In this work, we addressed different biological barriers for effective cancer treatment along with several strategies to overcome them by using ABC-based self-assembled nanostructures, with special emphasis in those that have the ability to act as responsive nanocarriers to internal or external environmental clues to trigger release of the payload. These nanocarriers have shown promising properties to revolutionize cancer treatment and diagnosis, but there are still challenges for their successful translation to clinical applications.

Reduction-responsive polymers for drug delivery in cancer therapy-Is there anything new to discover?

Among various types of stimuli-responsive drug delivery systems, reduction-responsive polymers have attracted great interest. In general, these systems have high stability in systemic circulation, however, they can respond quickly to differences in the concentrations of reducing species in specific physiological sites associated with a pathology. This is a particularly relevant strategy to target diseases in which hypoxic regions are present, as polymers which are sensitive to in-situ expressed antioxidant species can, through a local response, release a therapeutic at high concentration in the targeted site, and thus, improve the selectivity and efficacy of the treatment. At the same time, such reduction-responsive materials can also decrease the toxicity and side effects of certain drugs. To date, polymers containing disulfide linkages are the most investigated of the class of reduction-responsive nanocarriers, however, other groups such as selenide and diselenide have also been used for the same purpose. In this review article, we discussed the rationale behind the development of reduction-responsive polymers as drug delivery systems and highlight examples of recent progress. We include the most popular design methods to generate reduction-responsive polymeric carriers and their applications in cancer therapy, and question what areas may still need to be explored in a field with already a very large number of research articles. Finally, we consider the main challenges associated with the clinical translation of these nanocarriers and the future perspectives in this area. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

pH-sensitive curcumin conjugated micelles for tumor triggered drug delivery

Development of new drugs are confronted with some barriers and challenges, since these projects are mainly expensive, complex, time consuming with lack of success, there is an urgent need to reformulate the current poorly water soluble anti-cancer drugs. In this study, a new type of polymer-curcumin conjugates based on glycidyl azide polymer (GAP) was developed for cancer therapy. The copolymer was used for delivery of curcumin (CUR) as an anticancer drug to cancer cells. Our method is based on the facile conjugation of CUR to amine-containing polymeric vehicles through imine linkage bonds, which could remain stable in normal physiological condition while readily dissociate by an acidic environment and make the prodrug active to liberate its payload CUR to inhibit cell growth. The results demonstrated that fabricated amphiphilic PDCs were self-assembled into nanosized micelles in aqueous solution and the micelles showed an average size of 180 nm with a good polydispersity index. Drug release studies demonstrated that this nano-conjugate is fairly stable at physiologic environments but prone to mild acidic conditions which would trigger the release of conjugated CUR. Moreover, the PDCs micelles exhibited excellent cytotoxicity effect on 4T1 mouse breast cancer cell line but no significant toxicity was observed for the copolymer. In addition, the copolymer did not display remarkable toxicity against A. salina even at high doses of copolymer. In addition, the synthesized PDCs exhibited hemolysis lowers than 6%. The safety of copolymers as a drug vehicle was also confirmed by LD₅₀, since all mice which treated with 5000 mg/Kg (limited dose) were still alive after one week. Our findings revealed that these unique pH-sensitive PDCs may provide a promising approach for delivery of the anticancer drugs to cancer cells.[Formula: see text].

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.

Synthesis of Biocompatible Cholesteryl-Carboxymethyl Xylan Micelles for Tumor-Targeting Intracellular DOX Delivery

Patients with cancer suffer from severe side effects and reduced life quality, as chemotherapeutic drugs are cytotoxic toward normal cells as well as toward cancer cells. In recent years, nanoparticles have been explored as targeted drug delivery systems; however, problems such as toxicity and instability prevent their practical application. Here, we report the synthesis of cholesteryl-carboxymethyl xylan (CCMX) via an esterification reaction between the carboxyl group of carboxymethyl xylan and the hydroxyl group of cholesterol to form biocompatible micelles as a vehicle for targeted drugs. With its critical micelle concentration (CMC) depending on the degree of substitution (DS) of cholesteryl and ranging from 0.0024 to 0.017 mg/mL, CCMX could self-assemble and form nanoscale micelles in aqueous media. Taking doxorubicin (DOX) as a model drug, the drug encapsulation efficiency (EE%) of CCMX-3 (DS of 0.35 for cholesteryl) reached 91.3%, and this system exhibited excellent internalization ability, as verified by tumor cellular uptake tests. The results of in vitro cytotoxicity and in vivo antitumor activity tests of nude mice demonstrated that CCMX-3/DOX micelles effectively suppressed the growth of tumor cells by maintaining the cytotoxicity of commercial DOX injection while reducing the toxicity against normal cells and increasing the survival time.