Chitosan Oligosaccharide Lactate Coated Hydroxyapatite Nanoparticles as a Vehicle for the Delivery of Steroid Drugs and the Targeting of Breast Cancer Cells

Exploring the promising role of chitosan delivery systems in breast cancer treatment: A comprehensive review

Breast cancer presents a significant global health challenge, driving the development of novel treatment strategies for therapeutic interventions. Nanotechnology has emerged as a promising avenue for addressing this challenge, with Chitosan (CS) nanoparticles receiving prominence due to their unique characteristics and multitude of potential applications. This review provides a comprehensive overview of the role of Chitosan nanoparticles in breast cancer therapy. The review begins by emphasizing the prevalence and importance of breast cancer as a major health issue, underscoring the necessity for effective treatments. It then delves into the application of Chitosan nanoparticles in breast cancer therapy. One key aspect discussed is their role as carriers for anticancer drugs, enabling targeted delivery and improved cellular uptake. Furthermore, the review explores modified Chitosan nanoparticles and strategies for enhancing their efficacy and specificity in breast cancer treatment. It also examines Chitosan conjugates and hybrids, which offer innovative approaches for combination therapy. Additionally, metal and magnetic Chitosan nanoparticles are discussed spanning their capacity to assist in imaging, hyperthermia, as well as targeted drug delivery. In conclusion, the review summarizes the current research landscape regarding Chitosan nanoparticles for breast cancer therapy and offers insights into future directions. Overall, the review highlights the versatility, potential benefits, and future prospects of Chitosan nanoparticles in combating breast cancer.

Diacerein-loaded surface modified iron oxide microparticles (SMIOMPs): an emerging magnetic system for management of osteoarthritis via intra-articular injection

Introduction

Osteoarthritis (OA) is regarded as one of the most prevealent irreversible joint degenerative disorder worldwide. Recently, considerable interest in utilizing intra-articular (IA) injections for managing OA has been raised.

Methods

In this study, IA injectable surface modified iron oxide microparticles (SMIOMPs) loaded with Diacerein (DCN) were developed. The effects of formulation parameters on particle size, entrapment efficiency, and zeta potential were explored using factorial design. The optimized formulation was characterized regarding morphology and in vitro release. Differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR) were done to assess interactions. Further, sterilization and in vivo performance in rats with induced arthritis has been performed for the optimized formulation.

Results and Discussion

The selected optimized system included 2M FeCL3 and 1% chitosan as a surface modifier achieved high drug entrapment of 85.25% with a PS of 1.54 µm and sustained DCN release. Morphological examination of the optimized formulation revealed spherical particles with chitosan coat. DSC and FTIR results indicated the absence of undesired interactions between DCN and the used components. No significant change in the measured parameters was observed following sterilization using gamma radiation. In vivo assessment revealed superior performance for the optimized formulation in reducing cartilage inflammation and degradation. Plasma levels of tumor necrosis factor α and Interleukin-1 beta, as well as knee diameter, were significantly reduced in the treated groups compared to the untreated ones.

Conclusion

Overall, the results suggest that the proposed DCN-loaded SMIOMPs represent a promising advancement in the arena of cartilage regeneration.

Designing and the anticancer activity of chitosan and chitosan oligosaccharide lactate nanobeads loaded with Biginelli hybrid

This study focuses on the designing and characterization, and anticancer evaluation of chitosan-based nanoparticles (NPs) loaded (enriched) with a Biginelli hybrid compound (BH). NPs based on chitosan (CH) or chitosan oligosaccharide lactate (CHOL), are carefully designed to encapsulate a tetrahydropyrimidine derivative (BH) with already proven anticancer properties. The formulations were evaluated for their physicochemical properties, including particle size distribution and morphology, using techniques such as infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The cytotoxicity profiles were assessed on different cancer cell lines, showing a higher selectivity towards HeLa and A549 cells related to BH. BH-CH showed better cytotoxic profile related to BH-CHOL NPs. A cell cycle analysis revealed an accumulation of cells in the G2/M phase after a treatment with these NPs, indicating the ability to induce mitotic arrest in cancer cells. In summary, the results underscore the promising application of CH-based natural nanocarriers for the targeted delivery of Biginelli hybrids, showcasing a significant potential for further in vivo testing.

Anti-Cancer Activities of Nano Amorphous Calcium Phosphates toward Premalignant and Oral Cancer Cells

Despite advancements in treatment, the squamous cell carcinoma (OSCC) patient survival rate remains stagnant. Conventional therapies have limited effectiveness, necessitating novel agents. Our study aims to synthesize and characterize amorphous calcium phosphate nanoparticles (nACPs), assess their potential cytotoxic effects on premalignant and malignant OSCC cells, and investigate possible mechanisms of action. The morphological features of nACP were investigated by field emission scanning coupled with energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and particle size distribution (PSD). Then, we examined the effect of nACPs on nanoparticle uptake, cell adhesion, viability, invasion ability, cell cycle, and gene expression. nACP uptake was dose-dependent, induced limited selectivity in cytotoxicity between healthy and malignant cells, and affected cellular adhesion and invasion. Early apoptosis was the predominant type of cell death. The nACP effect on viability was verified by alterations in the genes associated with apoptosis and proliferation. A high concentration of nACP was shown to arrest the cell cycle progression in the G0/G1 phase of both malignant and premalignant cells. This type of nACP justifies the development of a strategy for its potential use as an anti-cancer agent and/or anti-cancer active carrier for various drugs in oral cancer treatments.

Chitosan- and hyaluronic acid-based nanoarchitectures in phototherapy: Combination cancer chemotherapy, immunotherapy and gene therapy

Cancer phototherapy has been introduced as a new potential modality for tumor suppression. However, the efficacy of phototherapy has been limited due to a lack of targeted delivery of photosensitizers. Therefore, the application of biocompatible and multifunctional nanoparticles in phototherapy is appreciated. Chitosan (CS) as a cationic polymer and hyaluronic acid (HA) as a CD44-targeting agent are two widely utilized polymers in nanoparticle synthesis and functionalization. The current review focuses on the application of HA and CS nanostructures in cancer phototherapy. These nanocarriers can be used in phototherapy to induce hyperthermia and singlet oxygen generation for tumor ablation. CS and HA can be used for the synthesis of nanostructures, or they can functionalize other kinds of nanostructures used for phototherapy, such as gold nanorods. The HA and CS nanostructures can combine chemotherapy or immunotherapy with phototherapy to augment tumor suppression. Moreover, the CS nanostructures can be functionalized with HA for specific cancer phototherapy. The CS and HA nanostructures promote the cellular uptake of genes and photosensitizers to facilitate gene therapy and phototherapy. Such nanostructures specifically stimulate phototherapy at the tumor site, with particle toxic impacts on normal cells. Moreover, CS and HA nanostructures demonstrate high biocompatibility for further clinical applications.

Advances in the preparation, characterization, and biological functions of chitosan oligosaccharide derivatives: A review

Chitosan oligosaccharide (COS), which represent the positively charged basic amino oligosaccharide in nature, is the deacetylated and degraded products of chitin. COS has become the focus of intensive scientific investigation, with a growing body of practical and clinical studies highlighting its remarkable health-enhancing benefits. These effects encompass a wide range of properties, including antibacterial, antioxidant, anti-inflammatory, and anti-tumor activities. With the rapid advancements in chemical modification technology for oligosaccharides, many COS derivatives have been synthesized and investigated. These newly developed derivatives possess more stable chemical structures, improved biological activities, and find applications across a broader spectrum of fields. Given the recent interest in the chemical modification of COS, this comprehensive review seeks to consolidate knowledge regarding the preparation methods for COS derivatives, alongside discussions on their structural characterization. Additionally, various biological activities of COS derivatives have been discussed in detail. Lastly, the potential applications of COS derivatives in biomedicine have been reviewed and presented.

Chitosan-functionalized bioplatforms and hydrogels in breast cancer: immunotherapy, phototherapy and clinical perspectives

Breast cancer is the most common and malignant tumor among women. Chitosan (CS)-based nanoparticles have been introduced into breast cancer therapy as a way to increase the targeted delivery of drugs and genes to the tumor site. CS nanostructures suppress tumorigenesis by enhancing both the targeted delivery of cargo (drug and gene) and its accumulation in tumor cells. The tumor cells internalize CS-based nanoparticles through endocytosis. Moreover, chitosan nanocarriers can also induce phototherapy-mediated tumor ablation. Smart and multifunctional types of CS nanoparticles, including pH-, light- and redox-responsive nanoparticles, can be used to improve the potential for breast cancer removal. In addition, the acceleration of immunotherapy by CS nanoparticles has also been achieved, and there is potential to develop CS-nanoparticle hydrogels that can be used to suppress tumorigenesis.

Enhanced Tumor Accumulation of Low-Molecular-Weight Hyaluronic Acid/Chitosan Nanocomplexes for Photothermal Therapy

Targeted phototheranostic nanosystems involving both cancer-specific near-infrared (NIR) fluorescence imaging and NIR light-induced phototherapy have shown great potential to improve cancer detection and treatment. In this study, a bifunctional nanocomplex based on low-molecular-weight hyaluronic acid (LMW-HA) and chitosan oligosaccharide lactate (COL) conjugating a zwitterionic NIR dye (ZW800-1) was rationally designed and prepared, and it was simultaneously used to enhance tumor accumulation and photothermal therapy (PTT). When HA-COL-ZW nanocomplexes were intravenously injected into mice bearing NCI-H460 tumors, HA-COL-ZW revealed increased tumor accumulation with prolonged tumor retention. Moreover, the ZW800-1 incorporated in HA-COL-ZW nanocomplexes showed excellent capability to convert NIR light into heat energy at the tumor site, acting as a PTT agent. Therefore, the targeted phototherapeutic HA-COL-ZW nanocomplex is a biocompatible and effective photothermal nanoagent, which could be a good candidate for future clinical use.

Synthesis of hydroxyapatite nanoparticles using Acacia falcata leaf extract and study of their anti-cancerous activity against cancerous mammalian cell lines

This study deals with the synthesis of hydroxyapatite nanoparticles (HAPnps) mediated by Acacia falcata leaf extract. Aggregates of needle-shaped crystalline nanostructures were confirmed by FE-SEM and TEM analysis. Well-defined rings in the SAED patterns corroborated the polycrystalline nature of the HAPnps. Individual elements present in the HAPnps were attested by the specific signals for Ca, P, and O in the EDS and XPS analyses. The distinct peaks observed in the XRD spectrum matched well with the HAP hexagonal patterns with a mean crystallite size of 55.04 nm. The FTIR study unveiled the coating of the nanoparticles with the biomolecules from Acacia falcata leaves. The suspension HAPnps exhibited polydispersity (0.446) and remarkable stability (zeta potential: - 31.9 mV) as evident from DLS studies. The pore diameter was 25.7 nm as obtained from BET analysis, suggesting their mesoporous nature. The HAPnps showed the cytotoxic effect on A549 lung and MDA-MB231 breast carcinoma cell lines, with an IC₅₀ value of 55 μg/mL. The distortion of the cell membrane and cell morphology, along with the chromatin condensation and cell necrosis on treatment with HAPnps were detected under fluorescence microscopy post acridine orange/ethidium bromide dye staining. This study reports the anti-cancerous potential of non-drug-loaded plant-mediated HAPnps. Therefore, the HAPnps obtained in this investigation could play a vital role in the biomedical field of cancer therapy.

Hydroxyapatite Biobased Materials for Treatment and Diagnosis of Cancer

Great advances in cancer treatment have been undertaken in the last years as a consequence of the development of new antitumoral drugs able to target cancer cells with decreasing side effects and a better understanding of the behavior of neoplastic cells during invasion and metastasis. Specifically, drug delivery systems (DDS) based on the use of hydroxyapatite nanoparticles (HAp NPs) are gaining attention and merit a comprehensive review focused on their potential applications. These are derived from the intrinsic properties of HAp (e.g., biocompatibility and biodegradability), together with the easy functionalization and easy control of porosity, crystallinity and morphology of HAp NPs. The capacity to tailor the properties of DLS based on HAp NPs has well-recognized advantages for the control of both drug loading and release. Furthermore, the functionalization of NPs allows a targeted uptake in tumoral cells while their rapid elimination by the reticuloendothelial system (RES) can be avoided. Advances in HAp NPs involve not only their use as drug nanocarriers but also their employment as nanosystems for magnetic hyperthermia therapy, gene delivery systems, adjuvants for cancer immunotherapy and nanoparticles for cell imaging.

Polymeric Nanotechnologies for the Treatment of Periodontitis: A Chronological Review

Periodontitis is a chronic infectious and inflammatory disease of periodontal tissues estimated to affect 70 - 80 % of all adults. At the same time, periodontium, the site of periodontal pathologies, is an extraordinarily complex plexus of soft and hard tissues, the regeneration of which using even the most advanced forms of tissue engineering continues to be a challenge. Nanotechnologies, meanwhile, have provided exquisite tools for producing biomaterials and pharmaceutical formulations capable of elevating the efficacies of standard pharmacotherapies and surgical approaches to whole new levels. A bibliographic analysis provided here demonstrates a continuously increasing research output of studies on the use of nanotechnologies in the management of periodontal disease, even when they are normalized to the total output of studies on periodontitis. The great majority of biomaterials used to tackle periodontitis, including those that pioneered this interesting field, have been polymeric. In this article, a chronological review of polymeric nanotechnologies for the treatment of periodontitis is provided, focusing on the major conceptual innovations since the late 1990s, when the first nanostructures for the treatment of periodontal diseases were fabricated. In the opening sections, the etiology and pathogenesis of periodontitis and the anatomical and histological characteristics of the periodontium are being described, along with the general clinical manifestations of the disease and the standard means of its therapy. The most prospective chemistries in the design of polymers for these applications are also elaborated. It is concluded that the amount of innovation in this field is on the rise, despite the fact that most studies are focused on the refinement of already established paradigms in tissue engineering rather than on the development of revolutionary new concepts.

Hormone receptor binding, selectivity and cytotoxicity of steroid D-homo lactone loaded chitosan nanoparticles for the treatment of breast and prostate cancer cells

Chemically modified steroids have a long history as anti-neoplastic drugs. Incorporation of a lactone moiety in the steroid nucleus, as in previously obtained 3β-acetoxy-17-oxa-17a-homoandrost-5-en-16-one (A) and 3β-hidroxy-17-oxa-17a-homoandrost-5-en-16-one (B), often results in enhanced anticancer properties. In this work, chitosan-based (Ch) nanoparticles were created and loaded with potent anticancer steroidal compounds, A and B. Changes to hormone receptor binding and cytotoxicity were then measured. In agreement with our previous results for A and B, A- and B-loaded Ch displayed cytotoxic properties against cancer cell lines. Both A-Ch and B-Ch showed activity toward estrogen negative breast cancer (MDA-MB-231) and androgen negative prostate cancer cell lines (PC-3). Greater selectivity toward cancer cells versus healthy lung fibroblast (MRC-5) was observed for B-Ch particles. Cell viability and cytotoxicity measurements after a recovery period indicate more robust recovery of healthy cells versus malignant cells. Compounds A and B or their Ch-encapsulated forms were shown to have negligible affinity for the ligand binding domain of estrogen receptor β or the androgen receptor in a fluorescent yeast screen, suggesting a lack of estrogenicity and androgenicity. Steroid-loaded chitosan nanoparticles display strong cytotoxicity towards MDA-MB-231 and PC-3 with a lack of hormone activity, indicating their safety and efficacy.

The Microstructure, Antibacterial and Antitumor Activities of Chitosan Oligosaccharides and Derivatives

Chitosan obtained from abundant marine resources has been proven to have a variety of biological activities. However, due to its poor water solubility, chitosan application is limited, and the degradation products of chitosan oligosaccharides are better than chitosan regarding performance. Chitosan oligosaccharides have two kinds of active groups, amino and hydroxyl groups, which can form a variety of derivatives, and the properties of these derivatives can be further improved. In this review, the key structures of chitosan oligosaccharides and recent studies on chitosan oligosaccharide derivatives, including their synthesis methods, are described. Finally, the antimicrobial and antitumor applications of chitosan oligosaccharides and their derivatives are discussed.

Systematic Review of Cancer Targeting by Nanoparticles Revealed a Global Association between Accumulation in Tumors and Spleen

Active targeting of nanoparticles toward tumors is one of the most rapidly developing topics in nanomedicine. Typically, this strategy involves the addition of cancer-targeting biomolecules to nanoparticles, and studies on this topic have mainly focused on the localization of such formulations in tumors. Here, the analysis of the factors determining efficient nanoparticle targeting and therapy, various parameters such as types of targeting molecules, nanoparticle type, size, zeta potential, dose, and the circulation time are given. In addition, the important aspects such as how active targeting of nanoparticles alters biodistribution and how non-specific organ uptake influences tumor accumulation of the targeted nanoformulations are discussed. The analysis reveals that an increase in tumor accumulation of targeted nanoparticles is accompanied by a decrease in their uptake by the spleen. There is no association between targeting-induced changes of nanoparticle concentrations in tumors and other organs. The correlation between uptake in tumors and depletion in the spleen is significant for mice with intact immune systems in contrast to nude mice. Noticeably, modulation of splenic and tumor accumulation depends on the targeting molecules and nanoparticle type. The median survival increases with the targeting-induced nanoparticle accumulation in tumors; moreover, combinatorial targeting of nanoparticle drugs demonstrates higher treatment efficiencies. Results of the comprehensive analysis show optimal strategies to enhance the efficiency of actively targeted nanoparticle-based medicines.

Blockade of CD73 using siRNA loaded chitosan lactate nanoparticles functionalized with TAT-hyaluronate enhances doxorubicin mediated cytotoxicity in cancer cells both in vitro and in vivo

Chemotherapy drugs are still one of the first treatment options used in many cancers; however, problems such as cytotoxic side effects on normal cells after systemic administration and resistance to treatment have reduced the use of chemotherapeutics day by day. Targeted delivery of these drugs to the tumor site and sensitization of cancer cells to death induced by chemotherapy drugs are ways that can overcome the limitations of the use of these drugs. In this study, we designed and generated a novel nanocarrier composed of chitosan lactate nanoparticles (NPs) functionalized by HIV-1 derived TAT peptide (Transactivating transcriptional activator) and hyaluronate (HA) to deliver CD73 siRNA and doxorubicin to 4T1 and CT26 cancer cells, both in vivo and in vitro, as a novel combinatorial treatment strategy. The CD73 molecule plays a key role in many cancer cell behaviors such as proliferation, angiogenesis, metastasis, imunosuppression, and resistance to chemotherapy. Therefore, we decided to reduce the side effects of DOX by simultaneously transmitting CD73 siRNA and DOX by CL-TAT-HA NPs, increase the susceptibility of cancer cells to DOX-induced cell death, and stimulate anti-tumor immune responses, for the first time. These results indicated that simultaneous transfer of CD73 siRNA and DOX to cancer cells (4 T1 and CT26) increased cell death and inhibited the prolifration and spread of cancer cells. Also, the preferential aggregation of NPs in the tumor microenvironment reduced tumor growh, promoted the survival of tumor-bearing mice, and induced anti-tumor immune responses. These findings indicate that CL-TAT-HA NPs are a good candidate for targeted siRNA/drug delivery to cancer cells and the simultaneous transfer of CD73 siRNA and DOX to cancer cells using this nanocarrier can be used to treat cancer.

Naturally-derived targeted therapy for wound healing: Beyond classical strategies

This review summarizes the four processes of wound healing in the human body (hemostasis, inflammatory, proliferation, and remodeling) and the most current research on the most important factors affecting cutaneous wound healing and the underlying cellular and/or molecular pathways. Local factors, including temperature, oxygenation, and infection, and systemic factors, such as age, diabetes, sex hormones, genetic components, autoimmune diseases, psychological stress, smoking and obesity are also addressed. A better understanding of the role of these factors in wound repair could result in the development of therapeutics that promote wound healing and resolve affected wounds. Additionally, natural products obtained from plants and animals are critical targets for the discovery of novel biologically significant pharmacophores, such as medicines and agrochemicals. This review outlines the most recent advances in naturally derived targeted treatment for wound healing. These are plant-derived natural products, insect-derived natural products, marine-derived natural products, nanomaterial-based wound-healing therapeutics (metal- and non-metal-based nanoparticles), and natural product-based nanomedicine to improve the future direction of wound healing. Natural products extracted from plants and animals have advanced significantly, particularly in the treatment of wound healing. As a result, the isolation and extraction of bioactive compounds from a variety of sources can continue to advance our understanding of wound healing. Undescribed bioactive compounds or unexplored formulations that could have a role in today's medicinal arsenal may be contained in the abundance of natural products and natural product derivatives.

Anodizing/Anaphoretic Electrodeposition of Nano-Calcium Phosphate/Chitosan Lactate Multifunctional Coatings on Titanium with Advanced Corrosion Resistance, Bioactivity, and Antibacterial Properties

The aim of this work was to investigate corrosion resistivity, bioactivity, and antibacterial activity of novel nano-amorphous calcium phosphate (ACP) potentially multifunctional composite coatings with and without chitosan oligosaccharide lactate (ChOL), ACP + ChOL/TiO₂ and ACP/TiO₂ ACP + ChOL/TiO₂, respectively, on the titanium substrate. The coatings were obtained by new single-step in situ anodization of the substrate to generate TiO₂ and the anaphoretic electrodeposition process of ACP and ChOL. The obtained coatings were around 300 ± 15 μm thick and consisted of two phases, namely, TiO₂ and hybrid composite phases. Both ACP/TiO₂ and ACP + ChOL/TiO₂ have improved corrosion stability, whereas the ACP + ChOL/TiO₂ coating showed better corrosion stability. It was shown that at the very start of the deposition process, the formation of the ChOL/TiO₂ layer takes place predominantly, which is followed by the inclusion of ChOL into ACP with simultaneous growth of TiO₂. This deposition mechanism resulted in the formation of strongly bonded uniform stable coating with high corrosion resistance. In vitro bioactivity was investigated by immersion of the samples in simulated body fluid (SBF). There is in-bone-like apatite formation on both ACP/TiO₂ and ACP + ChOL/TiO₂ surfaces upon immersion into SBF, which was proven by X-ray diffraction and Fourier transform infrared spectroscopy. While ACP/TiO₂ shows no antibacterial activity, ACP + ChOL/TiO₂ samples exhibited three- to fourfold decreases in the number of Staphylococcus aureus and Pseudomonas aeruginosa, respectively, after 420 min. The probable mechanism is binding ChOL with the bacterial cell wall, inhibiting its growth, altering the permeability of the cell membrane, and leading to bacterial death.

Enrichment of cancer-initiating cells from colon cancer cells through porous polymeric membranes by a membrane filtration method

Cancer-initiating cells (CICs) or cancer stem cells (CSCs) are primarily responsible for tumor initiation, growth, and metastasis and represent a few percent of the total tumor cell population. We designed a membrane filtration protocol to enrich CICs (CSCs) from the LoVo colon cancer cell line via nylon mesh filter membranes with 11 and 20 μm pore sizes and poly(lactide-co-glycolic acid)/silk screen (PLGA/silk screen) porous membranes (pore sizes of 20-30 μm). The colon cancer cell solution was filtered through the membranes to obtain a permeate solution. Subsequently, the cell culture medium was filtered through the membranes to collect the recovery solution where the cells attached to the membranes were rinsed off into the recovery solution. Then, the membranes were cultivated in the cultivation medium to collect the migrated cells from the membranes. The cells migrated from any membrane had higher expression of the CSC surface markers CD44 and CD133, had higher colony formation levels, and produced more carcinoembryonic antigen (CEA) than the colon cancer cells cultivated on conventional tissue culture plates (control). We established a method to enrich the CICs (CSCs) of colon cancer cells from migrated cells through porous polymeric membranes by the membrane filtration protocol developed in this study.

Limited hydrolysis and conjugation of zein with chitosan oligosaccharide by enzymatic reaction to improve functional properties

In order to improve its aqueous solubility and emulsifying function, zein was partially hydrolyzed by trypsin and conjugated to chitosan oligosaccharide lactate by transglutaminase. Hydrolysis and covalent linkage to chitosan oligosaccharide was confirmed by free amine content, gel electrophoresis, and infrared spectroscopy. Enzymatic glycosylation was optimized at pH 6, 44 °C, and 4 h to bind approximately 95% of the free amines in the hydrolysates to chitosan oligosaccharide. Hydrolysis and conjugation increased solubility of zein by 47.60% and 72.93%. Hydrolysis and conjugation also decreased surface hydrophobicity by more than 20% and more than doubled emulsifying activity index, emulsion stability index, and foaming capacity. This enzymatic modification has potential to be applied to improve functional properties of other prolamins.

Chitosan nanobeads loaded with Biginelli hybrids as cell-selective toxicity systems with a homogeneous distribution of the cell cycle in cancer treatment

Tetrahydropyrimidines are a class of azaheterocycles, also called Biginelli hybrids (obtained from the Biginelli reaction), that have attracted an enormous interest in the medicinal chemistry community in recent years, due to a broad biological activity, such as anticancer, antiviral, anti-inflammatory, antidiabetic, antituberculosis activities, etc. According to SciFinder®, more than 70 000 different Biginelli-like compounds have been covered in publications. However, although the Biginelli reaction can yield a large number of compounds with a broad range of activities, none of them have been captured in a carrier. In this study, chitosan-based (Ch) nanoparticles (NPs) containing three different molecules (Biginelli hybrids) were developed and tested for the first time as simple and promising vehicles for anticancer Biginelli-based drugs. The key features of NPs, such as size, surface morphology, drug encapsulation efficiency, and in vitro release were systematically investigated. Rather weak cell selectivity of pure Biginelli hybrids (A–C) to selected cancer cell lines has improved and this has been accompanied with two-to-four times stronger cytotoxic effect of A–C loaded Ch NPs, with a triple reduction in toxicity to healthy cells (MRC-5). It has been observed that the examined NPs induce apoptosis. The cell cycle analysis has confirmed the influence of A-loaded Ch (A-Ch), B-loaded Ch (B-Ch), and C-loaded Ch (C-Ch) on the cell cycle distribution, which was homogenously affected. This is the difference with regard to the effect of A, B, and C on the cell cycle. It has been established that the increased selectivity and antitumor activity of NPs are related to the presence of the carrier.

Chitosan nanoparticles containing tetrahydropyrimidines were developed and tested for the first time as simple and promising vehicles for anticancer Biginelli-based drugs.

Near-infra-red fluorescent chitosan oligosaccharide lactate for targeted cancer imaging and photothermal therapy

Photothermal therapy (PTT) is a promising approach for effective cancer treatment because of its non-invasive procedure, low toxicity to normal tissues, and high tumour ablation efficiency. Developing a PTT agent with precise tumour imaging capabilities is an essential prerequisite for effective PTT. In this study, we developed a bifunctional near-infra-red (NIR) fluorescent conjugate consisting of chitosan oligosaccharide lactate (COL) and the ZW800-1 NIR fluorophore (COL-ZW). We demonstrate that this conjugate is easy to use and that it is an effective theranostic agent for fluorescence-guided photothermal treatment. The temperature of COL-ZW increased by 62.3 °C after NIR laser irradiation (1.1 W/cm²) for 5 min in HT-29 tumour-bearing mice. The HT-29 tumours targeted by COL-ZW showed a remarkable decrease in tumour volume until a week after photothermal treatment. These in vivo results demonstrate that the bifunctional COL-ZW generates strong fluorescence and light-triggered PTT in tumour sites, indicating successful fluorescence-guided PTT. Importantly, no tumour recurrence or treatment-induced toxicity was observed after a single dose of COL-ZW with laser irradiation. Therefore, a combinatorial treatment with COL-ZW and NIR laser irradiation could serve as a promising strategy for photothermal cancer therapy.

Hydroxyapatite as a biomaterial - a gift that keeps on giving

The synthetic analogue to biogenic apatite, hydroxyapatite (HA) has a number of physicochemical properties that make it an attractive candidate for diagnosis, treatment of disease and augmentation of biological tissues. Here we describe some of the recent studies on HA, which may provide bases for a number of new medical applications. The content of this review is divided to different medical application modes utilizing HA, including tissue engineering, medical implants, controlled drug delivery, gene therapies, cancer therapies and bioimaging. A number of advantages of HA over other biomaterials emerge from this discourse, including (i) biocompatibility, (ii) bioactivity, (iii) relatively simple synthesis protocols for the fabrication of nanoparticles with specific sizes and shapes, (iv) smart response to environmental stimuli, (v) facile functionalization and surface modification through noncovalent interactions, and (vi) the capacity for being simultaneously loaded with a wide range of therapeutic agents and switched to bioimaging modalities for uses in theranostics. A special section is dedicated to analysis of the safety of particulate HA as a component of parenterally administrable medications. It is concluded that despite the fact that many benefits come with the usage of HA, its deficiencies and potential side effects must be addressed before the translation to the clinical domain is pursued. Although HA has been known in the biomaterials world as the exemplar of safety, this safety proves to be the function of size, morphology, surface ligands and other structural and compositional parameters defining the particles. For this reason, each HA, especially when it comes in a novel structural form, must be treated anew from the safety research angle before being allowed to enter the clinical stage.

Effective Targeting of Colon Cancer Cells with Piperine Natural Anticancer Prodrug Using Functionalized Clusters of Hydroxyapatite Nanoparticles

Targeted drug delivery offers great opportunities for treating cancer. Here, we developed a novel anticancer targeted delivery system for piperine (Pip), an alkaloid prodrug derived from black pepper that exhibits anticancer effects. The tailored delivery system comprises aggregated hydroxyapatite nanoparticles (HAPs) functionalized with phosphonate groups (HAP-Ps). Pip was loaded into HAPs and HAP-Ps at pH 7.2 and 9.3 to obtain nanoformulations. The nanoformulations were characterized using several techniques and the release kinetics and anticancer effects investigated in vitro. The Pip loading capacity was >20%. Prolonged release was observed with kinetics dependent on pH, surface modification, and coating. The nanoformulations fully inhibited monolayer HCT116 colon cancer cells compared to Caco2 colon cancer and MCF7 breast cancer cells after 72 h, whereas free Pip had a weaker effect. The nanoformulations inhibited ~60% in HCT116 spheroids compared to free Pip. The Pip-loaded nanoparticles were also coated with gum Arabic and functionalized with folic acid as a targeting ligand. These functionalized nanoformulations had the lowest cytotoxicity towards normal WI-38 fibroblast cells. These preliminary findings suggest that the targeted delivery system comprising HAP aggregates loaded with Pip, coated with gum Arabic, and functionalized with folic acid are a potentially efficient agent against colon cancer.

Anti-osteosarcoma effect of hydroxyapatite nanoparticles both in vitro and in vivo by downregulating the FAK/PI3K/Akt signaling pathway

Schematic representing the anti-cancer effects of nano-HAPs both in vitro and in vivo by downregulating the FAK/PI3K/Akt signaling pathway.

Waiting for Aπαταω: 250 Years Later

Scientific articles have been traditionally written from single points of view. In contrast, new knowledge is derived strictly from a dialectical process, through interbreeding of partially disparate perspectives. Dialogues, therefore, present a more veritable form for representing the process behind knowledge creation. They are also less prone to dogmatically disseminate ideas than monologues, alongside raising awareness of the necessity for discussion and challenging of differing points of view, through which knowledge evolves. Here we celebrate 250 years since the discovery of the chemical identity of the inorganic component of bone in 1769 by Johan Gottlieb Gahn through one such imaginary dialogue between two seasoned researchers and aficionados of this material. We provide the statistics on ups and downs in the popularity of this material throughout the history and also discuss important achievements and challenges associated with it. The shadow of Samuel Beckett's Waiting for Godot is cast over the dialogue, acting as its frequent reference point and the guide. With this dialogue presented in the format of a play, we provide hope that conversational or dramaturgical compositions of scientific articles - albeit virtually prohibited from the scientific literature of the day - may become more pervasive in the future.

Optimation for preparation of oligosaccharides from flaxseed gum and evaluation of antioxidant and antitumor activities in vitro

Flaxseed oligosaccharides (FGOS) were prepared by degradation of flaxseed gum (FG) using enzymatic method. Factors affecting the enzymatic hydrolysis of FG were investigated by single factor and orthogonal tests. In the optimum hydrolysis conditions (reaction time 12 h, temperature 50 °C, pH 4.5, cellulase concentration 100 U/mL), the reducing sugar ratio and extraction yield of FGOS were 33.6 ± 0.35% and 56.8 ± 0.41%, respectively. The average molecular weight of FGOS was about 1.6 kDa, which consists of mannose, galactose, glucose, arabinose, glucuronic acid, xylose, rhamnose, ribose, galacturonic acid. Fourier-transform infrared spectra and NMR indicated that FG was successfully degraded to FGOS. FGOS exhibited better antioxidant activities than FG on scavenging hydroxyl, ABTS and DPPH radicals. In vitro cytotoxicities experiments reveal FGOS acquire the ability of antiproliferation against HepG2 and Hela cells in a dose-dependent manner.

Polyglutamic acid-coordinated assembly of hydroxyapatite nanoparticles for synergistic tumor-specific therapy

Nanotechnology offers exciting and innovative therapeutic strategies in the fight against cancer. Nano-scale hydroxyapatite, the inorganic constituent of the hard tissues of humans and animals, is not only an ideal carrier for the delivery of drugs but also exerts selective inhibitory effects on tumor cells. To perform the dual functions, we propose polyglutamic acid-coordinated hydroxyapatite nanoparticles (HA-PGA NP) as both DOX delivery vehicle and sustained calcium flow supplier to achieve a synergistic, tumor-specific therapy in this study. With PGA as the coordinator, the HA-PGA NPs were easily assembled into spherical nano-clusters with low crystallinity. The excellent dispersibility and solubility in the tumor environment endowed the HA-PGA NPs with an improved internalization into the tumor cells, thereby causing a dramatic elevation in the intracellular calcium influx by about 40%, which further induced a cascade of mitochondrial membrane damage, ATP content reduction, and reinforced sensitivity to chemotherapy. After the encapsulation of the model drug DOX, a pH-responsive release profile was achieved via the degradation of the nanoparticles and the deprotonation of PGA in the acidic tumor micro-environment. Consequently, the hybrid system, with the synergistic effects of sustained DOX and calcium overload, exhibited selectively intensified toxicity to tumor cells. The in vivo test further confirmed that the current system exhibited highly selective tumor inhibition and reduced heart toxicity, thus representing an effective anti-tumor platform.

Nanostructured Calcium-based Biomaterials and their Application in Drug Delivery

In the past several decades, various types of nanostructured biomaterials have been developed. These nanostructured biomaterials have promising applications in biomedical fields such as bone repair, tissue engineering, drug delivery, gene delivery, antibacterial agents, and bioimaging. Nanostructured biomaterials with high biocompatibility, including calcium phosphate, hydroxyapatite, and calcium silicate, are ideal candidates for drug delivery. This review article is not intended to offer a comprehensive review of the nanostructured biomaterials and their application in drug delivery but rather presents a brief summary of the recent progress in this field. Our recent endeavors in the research of nanostructured biomaterials for drug delivery are also summarized. Special attention is paid to the synthesis and properties of nanostructured biomaterials and their application in drug delivery with the use of typical examples. Finally, we discuss the problems and future perspectives of nanostructured biomaterials in the drug delivery field.