Curcumin-cyclodextrin encapsulated chitosan nanoconjugates with enhanced solubility and cell cytotoxicity

Postbiotics-peptidoglycan, lipoteichoic acid, exopolysaccharides, surface layer protein and pili proteins-Structure, activity in wounds and their delivery systems

Chronic wound healing is a pressing global public health concern. Abuse and drug resistance of antibiotics are the key problems in the treatment of chronic wounds at present. Postbiotics are a novel promising strategy. Previous studies have reported that postbiotics have a wide range of biological activities including antimicrobial, immunomodulatory, antioxidant and anti-inflammatory abilities. However, several aspects related to these postbiotic activities remain unexplored or poorly known. Therefore, this work aims to outline general aspects and emerging trends in the use of postbiotics for wound healing, such as the production, characterization, biological activities and delivery strategies of postbiotics. In this review, a comprehensive overview of the physiological activities and structures of postbiotic biomolecules that contribute to wound healing is provided, such as peptidoglycan, lipoteichoic acid, bacteriocins, exopolysaccharides, surface layer proteins, pili proteins, and secretory proteins (p40 and p75 proteins). Considering the presence of readily degradable components in postbiotics, potential natural polymer delivery materials and delivery systems are emphasized, followed by the potential applications and commercialization prospects of postbiotics. These findings suggest that the treatment of chronic wounds with postbiotic ingredients will help provide new insights into wound healing and better guidance for the development of postbiotic products.

Bioresponsive and multifunctional cyclodextrin-based non-viral nanocomplexes in cancer therapy: Building foundations for gene and drug delivery, immunotherapy and bioimaging

The interest towards application of nanomaterials in field of cancer therapy is that the drawbacks of conventional therapies including chemoresistance, radio-resistance and lack of specific targeting of tumor cells can be solved by nanotechnology. Cyclodextrins (CDs) are amphiphilic cyclic oligosaccharides that can be present in three forms of α-, β- and γ-CDs, and they can be synthesized from natural sources. The application of CDs in cancer shows an increasing trend due to benefits of these nanocomplexes in improving solubility and bioavailability of current bioactives and therapeutics for cancer. CDs are widely utilized in delivery of drugs and genes in cancer therapy, and by targeted delivery of these therapeutics into target site, they improve anti-proliferative and anti-cancer potential. The blood circulation time and tumor site accumulation of therapeutics can be improved using CD-based nanostructures. More importantly, the stimuli-responsive types of CDs including pH-, redox- and light-sensitive types can accelerate release of bioactive compound at tumor site. Interestingly, the CDs are able to mediate photothermal and photodynamic impact in impairing tumorigenesis in cancer, enhancing cell death and improving response to chemotherapy. In improving the targeting ability of CDs, their surface functionalization with ligands has been conducted. Moreover, CDs can be modified with green products such as chitosan and fucoidan, and they can be embedded in green-based nanostructures to suppress tumorigenesis. The internalization of CDs into tumor cells can occur through endocytosis and this can be clethrin-, caveolae- or receptor-mediated endocytosis. Furthermore, CDs are promising candidates in bioimaging, cancer cell and organelle imaging as well as isolating tumor cells. The main benefits of using CDs in cancer therapy including sustained and low release of drugs and genes, targeted delivery, bioresponsive release of cargo, ease of surface functionalization and complexation with other nanostructures. The application of CDs in overcoming drug resistance requires more investigation.

Recent developments in natural biopolymer based drug delivery systems

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

Encapsulation of Clofazimine by Cyclodextran: Preparation, Characterization, and In Vitro Release Properties

This study aimed to evaluate and compare the efficacy of cyclodextrans (CIs) and cyclodextrins (CDs) in improving the water solubility of a poorly water-soluble drug, clofazimine (CFZ). Among the evaluated CIs and CDs, CI-9 exhibited the highest percentage of drug inclusion and the highest solubility. Additionally, CI-9 showed the highest encapsulation efficiency, with a CFZ:CI-9 molar ratio of 0.2:1. SEM analysis indicated successful formation of inclusion complexes CFZ/CI and CFZ/CD, accounting for the rapid dissolution rate of the inclusion complex. Moreover, CFZ in CFZ/CI-9 demonstrated the highest drug release ratio, reaching up to 97%. CFZ/CI complexes were found to be an effective means of protecting the activity of CFZ against various environmental stresses, particularly UV irradiation, compared to free CFZ and CFZ/CD complexes. Overall, the findings provide valuable insights into designing novel drug delivery systems based on the inclusion complexes of CIs and CDs. However, further studies are needed to investigate the effects of these factors on the release properties and pharmacokinetics of encapsulated drugs in vivo, in order to ensure the safety and efficacy of these inclusion complexes. In conclusion, CI-9 is a promising candidate for drug delivery systems, and CFZ/CI complexes could be a potential formulation strategy for the development of stable and effective drug products.

Anticancer potential of curcumin-cyclodextrin complexes and their pharmacokinetic properties

Cancer is one of the most common diseases throughout the world, with many treatment modalities currently being used, and new treatment strategies being sought. Most chemotherapeutic molecules have shown extensive toxicity for normal cells, which leads to severe adverse effects. Chemotherapy may also lead to drug resistance, which is one of the major obstacles to the clinical treatment of cancer. Curcumin, a polyphenolic natural compound, has long been considered a therapeutic molecule for a variety of diseases and possesses anti-cancer, anti-oxidant, and anti-inflammatory properties. However, its use is limited due to its hydrophobic nature, poor solubility in water at acidic or neutral pH, and limited bioavailability at the tumor site. Cyclodextrin complexes of curcumin increase curcumin's water solubility, as well as its physicochemical stability to hydrolysis and photochemical decomposition. The most common type of cyclodextrin used for pharmaceutical preparations is β-cyclodextrin. This review focuses on different curcumin-cyclodextrin formulations and compares their pharmacokinetic parameters and efficacy.

A Review of Cyclodextrin Encapsulation and Intelligent Response for the Release of Curcumin

To overcome the low water solubility and low bioavailability of curcumin (CUR), multiple delivery strategies have been proposed. Among these, cyclodextrin-based carriers have been widely used for the encapsulation and delivery of CUR. Cyclodextrins (CDs), as natural oligosaccharides, have been well known for their biodegradability, biocompatibility, non-toxicity, and internal hydrophobic and external hydrophilic structural features. This paper summarizes the recently reported CD-based carriers for encapsulating CUR. Particularly, the polymerization properties of CD self-assembly to enhance the encapsulation of CUR are discussed. In addition, the current progress on stimuli-responsive CD carriers for controlled release of CUR is described, which laid an important foundation for the development of CUR-based precision therapy in clinical practice. In conclusion, this review may provide ideas for the future development of a CD-based encapsulant for CUR.

Chitosan-Polyphenol Conjugates for Human Health

Human health deteriorates due to the generation and accumulation of free radicals that induce oxidative stress, damaging proteins, lipids, and nucleic acids; this has become the leading cause of many deadly diseases such as cardiovascular, cancer, neurodegenerative, diabetes, and inflammation. Naturally occurring polyphenols have tremendous therapeutic potential, but their short biological half-life and rapid metabolism limit their use. Recent advancements in polymer science have provided numerous varieties of natural and synthetic polymers. Chitosan is widely used due to its biomimetic properties which include biodegradability, biocompatibility, inherent antimicrobial activity, and antioxidant properties. However, due to low solubility in water and the non-availability of the H-atom donor, the practical use of chitosan as an antioxidant is limited. Therefore, chitosan has been conjugated with polyphenols to overcome the limitations of both chitosan and polyphenol, along with increasing the potential synergistic effects of their combination for therapeutic applications. Though many methods have been evolved to conjugate chitosan with polyphenol through activated ester-modification, enzyme-mediated, and free radical induced are the most widely used strategies. The therapeutic efficiency of chitosan-polyphenol conjugates has been investigated for various disease treatments caused by ROS that have shown favorable outcomes and tremendous results. Hence, the present review focuses on the recent advancement of different strategies of chitosan-polyphenol conjugate formation with their advantages and limitations. Furthermore, the therapeutic applicability of the combinatorial efficiency of chitosan-based conjugates formed using Gallic Acid, Curcumin, Catechin, and Quercetin in human health has been described in detail.

Combinatorial therapy using RNAi and curcumin nano-architectures regresses tumors in breast and colon cancer models

Cancer is a debilitating disease and one of the leading causes of death in the world. In spite of the current clinical management being dependent on applying robust pathological variables and well-defined therapeutic strategies, there is an imminent need for novel and targeted therapies with least side effects. RNA interference (RNAi) has gained attention due to its precise potential for targeting multiple genes involved in cancer progression. Nanoparticles with their enhanced permeability and retention (EPR) effect have been found to overcome the limitations of RNAi-based therapies. With their high transportation capacity, nanocarriers can target RNAi molecules to tumor tissues and protect them from enzymatic degradation. Accumulating evidence has shown that tyrosine kinase Ephb4 is overexpressed in various cancers. Therefore, we report here the development and pre-clinical validation of curcumin-chitosan-loaded: eudragit-coated nanocomposites conjugated with Ephb4 shRNA as a feasible bio-drug to suppress breast and colon cancers. The proposed bio-drug is non-toxic and bio-compatible with a higher uptake efficiency and through our experimental results we have demonstrated the effective site-specific delivery of this biodrug and the successfull silencing of their respective target genes in vivo in autochthonous knockout models of breast and colon cancer. While mammary tumors showed a considerable decrease in size, oral administration of the biodrug conjugate to Apc knockout colon models prolonged the animal survival period by six months. Hence, this study has provided empirical proof that the combinatorial approach involving RNA interference and nanotechnology is a promising alliance for next-generation cancer therapeutics.

The Effects of Curcumin Nanoparticles Incorporated into Collagen-Alginate Scaffold on Wound Healing of Skin Tissue in Trauma Patients

Wound healing is a biological process that is mainly crucial for the rehabilitation of injured tissue. The incorporation of curcumin (Cur) into a hydrogel system is used to treat skin wounds in different diseases due to its hydrophobic character. In this study, sodium alginate and collagen, which possess hydrophilic, low toxic, and biocompatible properties, were utilized. Collagen/alginate scaffolds were synthesized, and nanocurcumin was incorporated inside them; their interaction was evaluated by FTIR spectroscopy. Morphological studies investigated structures of the samples studied by FE-SEM. The release profile of curcumin was detected, and the cytotoxic test was determined on the L929 cell line using an MTT assay. Analysis of tissue wound healing was performed by H&E staining. Nanocurcumin was spherical, its average particle size was 45 nm, and the structure of COL/ALG scaffold was visible. The cell viability of samples was recorded in cells after 24 h incubation. Results of in vivo wound healing remarkably showed CUR-COL/ALG scaffold at about 90% (p < 0.001), which is better than that of COL/ALG, 80% (p < 0.001), and the control 73.4% (p < 0.01) groups at 14 days/ The results of the samples’ FTIR indicated that nanocurcumin was well-entrapped into the scaffold, which led to improving the wound-healing process. Our results revealed the potential of nanocurcumin incorporated in COL/ALG scaffolds for the wound healing of skin tissue in trauma patients.

Preparation and Characterization of Semi-IPN Cryogels Based on Polyacrylamide and Poly(N,N-dimethylaminoethyl methacrylate); Functionalization of Carrier with Monochlorotriazinyl-β-cyclodextrin and Release Kinetics of Curcumin

Curcumin (CCM) is a natural hydrophobic polyphenol known for its numerous applications in the food industry as a colorant or jelly stabilizer, and in the pharmaceutical industry due to its anti-inflammatory, antibacterial, antioxidant, anti-cancer, and anti-Alzheimer properties. However, the large application of CCM is limited by its poor solubility in water and low stability. To enhance the bioavailability of CCM, and to protect it against the external degradation agents, a novel strategy, which consists in the preparation of semi-interpenetrating polymer networks, (s-IPNs) based on poly(N,N-dimethylaminoethyl methacrylate) entrapped in poly(acrylamide) networks, by a cryogelation technique, was developed in this work. All s-IPN cryogels were characterized by SEM, EDX, FTIR, and swelling at equilibrium as a function of pH. Functionalization of semi-IPN cryogel with monochlorotriazinyl-β-cyclodextrin (MCT-β-CD) led to IPN cryogel. The release profile of CCM from the composite cryogels was investigated at 37 °C, in pH 3. It was found that the cumulative release increased with the increase of the carrier hydrophobicity, as a result of increasing the cross-linking degree, the content and the molar mass of PDMAEMA. Fitting Higuchi, Korsmeyer–Peppas, and first order kinetic models on the CCM release profiles indicated the diffusion as the main driving force of drug release from the composite cryogels.

Antitumoral Activities of Curcumin and Recent Advances to ImProve Its Oral Bioavailability

Curcumin, a main bioactive component of the Curcuma longa L. rhizome, is a phenolic compound that exerts a wide range of beneficial effects, acting as an antimicrobial, antioxidant, anti-inflammatory and anticancer agent. This review summarizes recent data on curcumin's ability to interfere with the multiple cell signaling pathways involved in cell cycle regulation, apoptosis and the migration of several cancer cell types. However, although curcumin displays anticancer potential, its clinical application is limited by its low absorption, rapid metabolism and poor bioavailability. To overcome these limitations, several curcumin-based derivatives/analogues and different drug delivery approaches have been developed. Here, we also report the anticancer mechanisms and pharmacokinetic characteristics of some derivatives/analogues and the delivery systems used. These strategies, although encouraging, require additional in vivo studies to support curcumin clinical applications.

A Novel Folic Acid Receptor-Targeted Drug Delivery System Based on Curcumin-Loaded β-Cyclodextrin Nanoparticles for Cancer Treatment

Purpose

A novel folate receptor-targeted β-cyclodextrin (β-CD) drug delivery vehicle was constructed to improve the bioavailability, biosafety, and drug loading capacity of curcumin. Controlled release and targeted delivery was achieved by modifying the nanoparticles with folic acid (FA).

Methods

Folate-conjugated β-CD-polycaprolactone block copolymers were synthesized and characterized. Curcumin-loaded nanoparticles (FA-Cur-NPs) were structured by self-assembly. The physicochemical properties, stability, release behavior and tumor-targeting ability of the fabricated nanoparticles were studied.

Results

The average particle size and drug loading of FA-Cur-NPs was 151.8 nm and 20.27%, respectively. Moreover, the FA-Cur-NPs exhibited good stability in vitro for 72 h. The drug release profiles showed that curcumin from FA-Cur-NPs was released significantly faster in a pH 6.4 phosphate buffered solution (PBS) than in pH 7.4, indicating that curcumin can be enriched around the tumor site compared with normal cells. Additionally, the internalization of FA-Cur-NPs was aided by FA receptor-mediated endocytosis, and its cytotoxicity was proportional to the cellular uptake efficiency. Furthermore, in vivo studies confirmed that FA-Cur-NPs exhibited marked accumulation in the tumor site and excellent antitumor activity.

Conclusion

These findings suggest that FA-Cur-NPs are a promising approach for improving cancer therapy through active targeting and controllable release.

Therapeutic Effects of Curcumin against Bladder Cancer: A Review of Possible Molecular Pathways

There are concerns about the increased incidence of cancer both in developing and developed countries. In spite of recent progress in cancer therapy, this disease is still one of the leading causes of death worldwide. Consequently, there have been rigorous attempts to improve cancer therapy by looking at nature as a rich source of naturally occurring anti-tumor drugs. Curcumin is a well-known plant-derived polyphenol found in turmeric. This compound has numerous pharmacological effects such as antioxidant, anti-inflammatory, antidiabetic and anti-tumor properties. Curcumin is capable of suppressing the growth of a variety of cancer cells including those of bladder cancer. Given the involvement of various signaling pathways such as PI3K, Akt, mTOR and VEGF in the progression and malignancy of bladder cancer, and considering the potential of curcumin in targeting signaling pathways, it seems that curcumin can be considered as a promising candidate in bladder cancer therapy. In the present review, we describe the molecular signaling pathways through which curcumin inhibits invasion and metastasis of bladder cancer cells.

Synergistic Antioxidant and Antibacterial Activity of Curcumin-C3 Encapsulated Chitosan Nanoparticles

BACKGROUND

Recent studies have focused on the nanoformulations of curcumin to enhance its solubility and bioavailability. The medicinal properties of curcumin-C3 complex, which is a combination of three curcuminoids (curcumin, demethoxycurcumin and bisdemethoxycurcumin) is less explored.

OBJECTIVE

The aim of this study was to prepare curcumin-C3 encapsulated in chitosan nanoparticles, characterize and evaluate their antioxidant and antibacterial potential.

METHODS

Ionic gelation method was used to prepare curcumin-C3 nanoparticles and was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy and nanoparticle tracking analysis. In vitro assays were performed to assess drug release, antioxidant and antibacterial activities.

RESULTS

Curcumin-C3-chitosan nanoparticle showed an increased entrapment efficiency of >90%, drug release and improved antioxidant potential. Moreover, curcumin-C3-chitosan nanoparticle showed stronger inhibition of Escherichia coli and Staphylococcus aureus.

CONCLUSION

Chitosan is a suitable carrier for curcumin-C3 nanoparticle and can be used as a drug delivery system in the treatment of inflammatory and bacterial diseases.

PGMD/curcumin nanoparticles for the treatment of breast cancer

The present study aims at developing PGMD (poly-glycerol-malic acid-dodecanedioic acid)/curcumin nanoparticles based formulation for anticancer activity against breast cancer cells. The nanoparticles were prepared using both the variants of PGMD polymer (PGMD 7:3 and PGMD 6:4) with curcumin (i.e. CUR NP 7:3 and CUR NP 6:4). The size of CUR NP 7:3 and CUR NP 6:4 were found to be ~ 110 and 218 nm with a polydispersity index of 0.174 and 0.36, respectively. Further, the zeta potential of the particles was - 18.9 and - 17.5 mV for CUR NP 7:3 and CUR NP 6:4, respectively. The entrapment efficiency of both the nanoparticles was in the range of 75-81%. In vitro anticancer activity and the scratch assay were conducted on breast cancer cell lines, MCF-7 and MDA-MB-231. The IC50 of the nanoformulations was observed to be 40.2 and 33.6 μM at 48 h for CUR NP 7:3 and CUR NP 6:4, respectively, in MCF-7 cell line; for MDA-MB-231 it was 43.4 and 30.5 μM. Acridine orange/EtBr and DAPI staining assays showed apoptotic features and nuclear anomalies in the treated cells. This was further confirmed by western blot analysis that showed overexpression of caspase 9 indicating curcumin role in apoptosis.

Cytotoxicity Effects of Curcumin Loaded on Chitosan Alginate Nanospheres on the KMBC-10 Spheroids Cell Line

Purpose

Breast cancer is one of the most lethal types of cancer in women. Curcumin showed therapeutic potential against breast cancer, but applying that by itself does not lead to the associated health benefits due to its poor bioavailability, which appears to be primarily due to poor absorption, rapid metabolism, and rapid elimination. Moreover, poor water solubility of curcumin causes accumulation of a high concentration of curcumin and so decrease its permeability to the cell. Many strategies are employed to reduce curcumin metabolism such as adjuvants and designing novel delivery systems. Therefore, in this study sodium alginate and chitosan were used to synthesize the hydrogels that are known as biocompatible, hydrophilic and low toxic drug delivery systems. Also, folic acid was used to link to chitosan in order to actively targetfolate receptors on the cells.

Methods

Chitosan-β-cyclodextrin-TPP-Folic acid/alginate nanoparticles were synthesized and then curcumin was loaded on them. Interaction between the constituents of the particles was characterized by FTIR spectroscopy. Morphological structures of samples were studied by FE-SEM. Release profile of curcumin was determined by dialysis membrane. The cytotoxic test was done on the Kerman male breast cancer (KMBC-10) cell line by using MTT assay. The viability of cells was detected by fluorescent staining. Gene expression was investigated by real-time PCR.

Results

The encapsulation of curcumin into nano-particles showed an almost spherical shape and an average particle size of 155 nm. In vitro cytotoxicity investigation was indicated as dose-respond reaction against cancer breast cells after 24 h incubation. On the other hand, in vitro cell uptake study revealed active targeting of CUR-NPs into spheroids. Besides, CXCR₄ expression was detected about 30-fold less than curcumin alone. The CUR-NPs inhibited proliferation and increased apoptosis in spheroid human breast cancer cells.

Conclusion

Our results showed the potential of NPs as an effective candidate for curcumin delivery to the target tumor spheroids that confirmed the creatable role of folate receptors.

Structural Characterization of a Cyclodextrin/l-menthol Inclusion Complex in the Solid-state by Solid-state NMR and Vibrational Circular Dichroism

Hydrophobic and volatile flavor molecules can be encapsulated inside cyclodextrins (CyDs). Inclusion complexes are frequently used in solid or dispersed states in preserved food and cosmetics. In this study, the solid-state structures of spray-dried inclusion complexes of l-menthol in α-CyD and β-CyD were analyzed using ¹³C solid-state NMR and vibrational circular dichroism (VCD). The NMR signals of l-menthol and CyDs were identified in the physical mixture and the l-menthol inclusion complex of α- and β-CyD. The NMR signal of the isopropyl-methyl group of menthol in the α-CyD inclusion complex exhibited a large low-field shift, which suggested a steric hindrance between menthol and α-CyD. VCD exhibited specific changes in the intensity of bands corresponding to C-C vibrations in α-CyD and O-C stretching vibrations in l-menthol. Our results indicated that l-menthol specifically fitted the narrow space within α-CyD. The combined solid-state NMR and VCD analysis provided structural insights into the flavor inclusion complex in the solid-state.

Stoichiometrically Governed Curcumin Solid Dispersion and Its Cytotoxic Evaluation on Colorectal Adenocarcinoma Cells

Background

Colorectal cancer (CRC) is the third most commonly occurring cancer in men and the second most commonly occurring cancer in women. Curcumin (CMN) is obtained from a natural source and has no toxicity, even at high doses (8,000 mg/kg body weight in 24 hours) and was determined to have anticancer potency on several kinds of carcinoma. However, its medical applications were limited because of its low solubility and poor bioavailability.

Materials and Methods

To improve the medical applications of CMN, various hydrophilic carriers such as poloxamer 407 (PMX-407), poloxamer 188 (PMX-188), Gelucire 50/13 (Gel-50/13), and mannitol (MNL) were used to prepare a binary complex solid dispersion (SD). These binary SDs were characterized for aqueous solubility in various solvents. Physical stability, thermal behaviors, and morphology were determined by Fourier transform infrared spectrophotometric analysis, powder X-ray diffraction analysis, thermogravimetric analysis, differential scanning calorimetric analysis, scanning electron microscopy, dynamic light scattering study, and the novel dyeing test. In vitro drug release was determined by dissolution study. Based on the characterization, the better SD complex was optimized using Box-Behnken design (BBD). The cytotoxicity and apoptosis study of prepared CMN (C-SD) were used to test for colorectal adenocarcinoma cell lines.

Results

These results showed that the solubility of CMN is greatly improved after complexation with PXM-407 in SD. CMN is practically insoluble in water at acidic and neutral pH; however, the SD of CMN with PXM-407 produced significant improvement in solubility (1.266±0.0242 mg/mL) and dissolution (91.36±0.431% at 30 minutes); similarly, these data fit with a phase solubility study and in silico molecular modeling. Moreover, the solid-state characterization revealed that the SD complex exhibits the intermolecular hydrogen bond with drug and carrier. Also, the complex does not undergo any chemical modification owing to the amorphous form, and the dye test showed better coloring impact indicating the solubility of CMN. The cell cycle arrest confirmed at G2/M phase from flow cytometry analysis, and Western blot investigation was recognized molecular level cell death and the complex induced more exploit DNA during apoptosis.

Conclusion

This study confirmed that the ideal stoichiometric ratio of CMN with carrier to enhance its solubility was 1:1. This molecular complex of PXM-407 was found to be more effective against colorectal cancer (CRC) than pure CMN.

Cyclodextrin Based Nanoparticles for Drug Delivery and Theranostics

Colloidal nanoparticulate technology has been described in the literature as a versatile drug delivery system. But it possesses some inherent lacunae in their formulation. Cyclodextrins (CDs) have been extensively reported for the solubility enhancement of poorly water-soluble drugs. The CDs can cause intervention in aspects related to nanoparticles (NPs) that include improving drug loading in nano-system, improving stability, site-specific/targeted drug delivery, improving solubility profile and absorption of the drug in nanosystem with consequent improvement in bioavailability, with the possibility of controlled release, safety and efficacy. They find application in for simultaneous diagnosis and therapeutics for better treatment procedures. The current communication is focused on the application of CDs to overcome troubles in nanoparticulate formulation and enhancement of their performance. It also envisages the theranostic aspects of CDs.

Antioxidant, antibacterial and anti-cancer activities of β-and γ-CDs/curcumin loaded in chitosan nanoparticles

Curcumin, as a naturally occurring polyphenol, has been extensively used as anticancer and antioxidant agent due to its ability to protect cells from oxidative damage. In the present study, we have prepared highly soluble CUR-β-cyclodextrin (β-CD) and γ-cyclodextrin (γ-CD) hollow spheres. UV-Vis method was employed to approve the successful formation of the inclusion complex where the aromatic ring of CUR has been encapsulated by the hydrophobic cavity of CDs. CUR-CDs were then encapsulated into positively charged biodegradable chitosan (CUR-CDs-CS) nanoparticles. The CUR-CD-CS were characterized by UV-Vis, FTIR, ¹HNMR, XRD, SEM analysis. Antibacterial efficacy was evaluated by measuring the zone of inhibition scale and MIC value which was recorded as 32 μg/mL and 64 μg/mL for both Gram positive S. aureus and Gram negative E. coli bacteria respectively. We tested the efficacy of these CUR-CD-CS nanoparticles in A549 cell lines using MTT assay and investigated its cellular uptake mechanism. Our results demonstrated that CUR-CD-CS nanoparticles showed superior in vitro release performance and higher cytotoxicity in A549 cell line among all tested formulations. Antioxidant activity and release behavior of the curcumin-loaded CDs-CS was investigated. The IC₅₀ value for CUR/CD-CS was estimated based on their inhibition percent-concentration curves using DPPH assay.

Preparation, characterization and antitumor activity of a cationic starch-derivative membrane embedded with a β-cyclodextrin/curcumin inclusion complex

A membrane of cationic starch-derivative/poly(vinyl alcohol) was prepared and utilized as a support to immobilize a β-cyclodextrin/curcumin inclusion complex. The resulting material (denote as β-CD/CUR-MBN) was characterized in detail by different techniques. In vitro experiments revealed that β-CD/CUR-MBN enables the controlling of the curcumin release process, which is guided by the relaxation of the polymer matrix. Moreover, cytotoxic assays were performed to investigate the effect of β-CD/CUR-MBN on two cancer cell lines (melanoma and glioblastoma). The results showed that the polymeric membrane exerts higher cytotoxicity against these cells than free curcumin. Also, β-CD/CUR-MBN exerted a prolonged cytotoxic effect (up to 96 h), even using a low concentration (50 μg mL^-1), indicating that the curcumin in the polymeric membrane showed increased bioavailability under the tested condition. β-CD/CUR-MBN was non-cytotoxic against normal cells suggesting a specific action of this material against target cancer cells. The results reported here allow ranks β-CD/CUR-MBN as a promising biomaterial to act as a local drug delivery system to treat cancer.

Anti-breast cancer activity of resveratrol encapsulated in liposomes

Resveratrol (RES) is a naturally occurring and effective drug for tumor prevention and treatment. However, its low levels of aqueous solubility, stability, and poor bioavailability limit its application, especially when used as a free drug. In this study, RES was loaded into peptide and sucrose liposomes (PSL) to enhance the physico-chemical properties of RES and exploit RES delivery mediated by liposomes to effectively treat breast cancer. RES loaded PSL (the complex: PSL@RES) were stable, had a good RES encapsulation efficiency, and prolonged RES-release in vitro. PSL@RES was exceptionally efficient for inhibiting the growth of cancer cells, as the IC50 of PSL@RES in MCF-7 cells was found to be only 20.89 μmol L-1. The therapeutic efficacy of PSL@RES was evaluated in mice bearing breast cancer. The results showed that PSL@RES at a dosage of 5 mg kg-1 was more effective than 10 mg kg-1 free RES, and PSL@RES inhibited tumor growth completely at a dosage of 10 mg kg-1. PSL@RES induced apoptosis in breast tumor by upregulation of p53 expression. This then downregulated Bcl-2 and upregulated Bax, thereby inducing Caspase-3 activation. More importantly, encapsulation of RES within peptide liposomes greatly reduced the toxicity of free RES to mice. Overall, the simple formulation of liposomal nanocarriers of RES developed in this study produces satisfactory outcomes to encourage further applications of liposomal carriers for the treatment of breast cancer.

Curcumin-Loaded Nanostructured Lipid Carrier Modified with Partially Hydrolyzed Ginsenoside

The objective of the present study was to investigate the effect of partially hydrolyzed ginsenoside on the physicochemical properties and in vitro release of curcumin from phospholipid-based nanostructured lipid carrier (NLC). NLC formulas modified with partially hydrolyzed ginsenoside (NLC-PG) were prepared with different amounts of ginsenoside using the conventional hot-melt method. The average particle size of curcumin-loaded NLC-PG ranged from 150 to 200 nm, and polydispersity index was in the range of 0.101-0.177, indicating monodispersed particle size distribution. Optical microscopy showed no sedimentation or recrystallization of curcumin even at 10,000 μg/ml concentration as NLC-PG in distilled water, indicating significantly enhanced solubility. TEM image showed that the nanoparticles were monodispersed with a multilayered core/shell structure. X-ray diffraction and FTIR spectroscopy showed that curcumin was amorphous in the NLC-PG, and there was no interaction between curcumin and the excipients. In vitro release study using simulated gastric/intestinal fluid media revealed that the release rate (J_ss) of curcumin from the NLC-PG increased as a function of the ginsenoside content in the lipid carrier. Moreover, the J_ss of curcumin kept gradually increasing in the presence of lipase, whereas in the presence of viscozyme, it sharply increased until the ginsenoside content reached 9.09% and subsequently plateaued. Partially hydrolyzed ginsenoside increased the J_ss of curcumin from curcumin-loaded NLC-PG and therefore may be useful for improving the bioavailability of curcumin.

Evaluation of epithelial transport and oxidative stress protection of nanoengineered curcumin derivative-cyclodextrin formulation for ocular delivery

Ocular drug delivery has been a well-known route for the drug administration for the treatment of ocular diseases. However, numerous anatomical and physiological barriers prevailing in the eye itself create considerable challenges for achieving the necessitated therapeutic efficacy along with ocular bioavailability. However, recent advances in nanoengineered strategies hold definite promises in terms of devising improved ophthalmic medicines for the effective drug delivery to target the sites with enhanced ocular bioavailability. Curcumin, a hydrophobic polyphenol yellow colored compound, and its metabolic reduced product, tetrahydrocurcumin (THC), have been known for their beneficial pharmacological functions, such as anti-inflammatory or anti-oxidant activities at various tissue sites. However, the low aqueous solubility of these compounds results in their poor bioavailability, thereby limiting their widespread application. Therefore, in the present study, we investigated the changes in drug solubility by forming inclusion complexes with different derivatives of hydroxypropyl (HP)-cyclodextrins (CD). To this end, the spray drying technique was used for nanoengineering curcumin or THC-loaded formulations to improve the stability of formulations during the storage. The formulations were characterized in terms of physicochemical properties and cellular permeability. The results demonstrated that the encapsulation of curcumin (or THC) into the HP-CDs significantly increased the drug solubility and enhanced the corneal and retinal epithelial permeability. Curcumin or THC complexes in HP-CDs with improved bioavailability also induced anti-oxidant activity (SOD1, CAT1, and HMOX1) in higher levels in the ocular epithelial cells and showed oxidative protection effects in rabbit cornea tissues that will boost up their application in ocular medicine.

Mesoporous Silica Nanomaterials: Versatile Nanocarriers for Cancer Theranostics and Drug and Gene Delivery

Mesoporous silica nanomaterials (MSNs) have made remarkable achievements and are being thought of by researchers as materials that can be used to effect great change in cancer therapies, gene delivery, and drug delivery because of their optically transparent properties, flexible size, functional surface, low toxicity profile, and very good drug loading competence. Mesoporous silica nanoparticles (MSNPs) show a very high loading capacity for therapeutic agents. It is well known that cancer is one of the most severe known medical conditions, characterized by cells that grow and spread rapidly. Thus, curtailing cancer is one of the greatest current challenges for scientists. Nanotechnology is an evolving field of study, encompassing medicine, engineering, and science, and it has evolved over the years with respect to cancer therapy. This review outlines the applications of mesoporous nanomaterials in the field of cancer theranostics, as well as drug and gene delivery. MSNs employed as therapeutic agents, as well as their importance and future prospects in the ensuing generation of cancer theranostics and drug and therapeutic gene delivery, are discussed herein. Thus, the use of mesoporous silica nanomaterials can be seen as using one stone to kill three birds.

Chitosan-based delivery systems for curcumin: A review of pharmacodynamic and pharmacokinetic aspects

Effective drug delivery is one of the most important issues associated with the administration of therapeutic agents that have low oral bioavailability. Curcumin is an active ingredient in the turmeric plant, which has low oral bioavailability due to its poor aqueous solubility. One strategy that has been considered for enhancing the aqueous solubility, and, thus, its oral bioavailability, is the use of chitosan as a carrier for curcumin. Chitosan is a biodegradable and biocompatible polymer that is relatively water-soluble. Therefore, various studies have sought to improve the aqueous solubility of chitosan. The use of different pharmaceutical excipients and formulation strategies has the potential to improve aqueous solubility, formulation processing, and the overall delivery of hydrophobic drugs. This review focuses on various methods utilized for chitosan-based delivery of curcumin.

Advances of nanosystems containing cyclodextrins and their applications in pharmaceuticals

For many years, researchers have worked with supramolecular structures involving inclusion complexes with cyclodextrins. These studies have resulted in new commercially available drugs which have been of great benefit. More recently, studies using nanoparticles, including nanosystems containing cyclodextrins, have become a focus of academic research due to the versatility of the systems and their remarkable therapeutic potential. This review focuses on studies published between 2002 and 2018 involving nanosystems containing cyclodextrins. We consider the type of nanosystems, their importance in a health context, the physicochemical techniques used to show the quality of these systems and their potential for the development of novel pharmaceutical formulations. These have been developed in recent studies which have mainly been focusing on basic science with no clinical trials as yet being performed. This is important to note because it means that the studies do not include any toxicity tests. Despite this limitation, the characterization assays performed suggest that these new formulations may have therapeutic potential. However, more research is required to assess the efficacy and safety of these nanosystems.

N-(2-Hydroxy)-propyl-3-trimethylammonium, O-Mysristoyl Chitosan Enhances the Solubility and Intestinal Permeability of Anticancer Curcumin

An amphiphilic derivative of chitosan containing quaternary ammonium and myristoyl groups, herein named as ammonium myristoyl chitosan (DMCat), was synthesized by reacting glycidyltrimethylammonium chloride (GTMAC) and myristoyl chitosan (DMCh). The success of the modification was confirmed using Fourier-transform infrared spectroscopy (FTIR) and ¹H nuclear magnetic resonance (NMR) spectroscopy. The average degrees of alkylation and quaternization (DQ¯) were determined by using ¹H NMR and conductometric titration. The zeta potential of the micelles was higher than 28 mV while its average size and encapsulation efficiency ranged from 280 nm to 375 nm and 68% to 100%, respectively. The in vitro cytotoxicity of the unloaded and curcumin (CUR)-loaded micelles was tested against Caco-2 and HT29-MTX intestinal epithelial cell lines. The results showed no cytotoxic effect from loaded and unloaded micelles as compared to free CUR. In the permeability test, it was observed that both types of micelles, i.e., DMCh and DMCat, improved CUR permeability. Additionally, higher permeability was verified for both systems in Caco-2/HT29-MTX:Raji B because of the mucoadhesive character of chitosan and its ability to open tight junctions. The results indicated that DMCat micelles, due to the physico-chemical, improved characteristics may be a promising carrier to encapsulate CUR aiming cancer therapy.

Pluronic-Based Mixed Polymeric Micelles Enhance the Therapeutic Potential of Curcumin

Curcumin is a naturally occurring constituent of turmeric that is a good substitute for synthetic medicines for the treatment of different diseases, due to its comparatively safer profile. However, there are certain shortcomings that limit its use as an ideal therapeutic agent. In order to overcome these drawbacks, we prepared novel curcumin-loaded mixed polymeric micelles using different biocompatible polymers by the thin-film hydration method. We investigated the critical micelle concentration and temperature, drug loading and encapsulation efficiency, and minimum inhibitory concentration by spectrophotometry. Surface morphology, stability, particle size, drug-polymer interaction, and physical state of the prepared formulations were investigated using scanning electron microscopy, zeta potential, particle size analyzer, Fourier-transform infrared spectroscopy, and X-ray diffraction, respectively. The drug loading and entrapment efficiency were significantly increased (P < 0.01) when curcumin was encapsulated with pluronic-based mixed polymeric micelles as compared to that of pluronic-based micelles alone. In vitro studies exhibited that pluronic-based mixed polymeric micelles significantly increased anticancer (P < 0.01), antimicrobial (P < 0.001), antioxidant (P < 0.001), and α-amylase inhibitory (P < 0.001) activities when compared to pure curcumin and/or pluronic-based micelles alone. These findings suggest that the formation of mixed polymeric micelles increases the stability and solubility of curcumin.

Advancements and Challenges in Multidomain Multicargo Delivery Vehicles

Reparative and regenerative processes are well-orchestrated temporal and spatial events that are governed by multiple cells, molecules, signaling pathways, and interactions thereof. Yet again, currently available implantable devices fail largely to recapitulate nature's complexity and sophistication in this regard. Herein, success stories and challenges in the field of layer-by-layer, composite, self-assembly, and core-shell technologies are discussed for the development of multidomain/multicargo delivery vehicles.

Augmentation of therapeutic potential of curcumin using nanotechnology: current perspectives

Curcumin, an active principle of Curcuma longa, is extracted from the rhizome. Its therapeutic efficiency has been proved using various in vitro and in vivo models. Inflammatory, neoplastic and preneoplastic diseases are the major targets using curcumin as therapeutic agent. Feasible clinical formulations could not be obtained because of its lack of solubility, stability and higher degradation rate. Recently, many techniques have been evolved to improve the physicochemical properties of pharmacological compounds, thereby increasing their biological activity. Curcumin has been developed using various techniques, particularly micro and nanotechnology to improve its stability and bioavailability. This review focuses on the studies pertaining to the delivery of curcumin in the form of micro and nanosize formulations for the treatment of a variety of diseases.

Evaluation of mesoporous silica nanoparticles for oral drug delivery - current status and perspective of MSNs drug carriers

The oral pathway is considered as the most common method for drug administration, although many drugs, especially the highly pH- and/or enzymatic biodegradable peptide drugs, are very difficult to formulate and achieve a good intestinal absorption. Efficient systematic absorption of an active substance, delivered via oral ingestion, is only achievable if the drug (1) is substantially present as a solution in the gastrointestinal tract, (2) is able to penetrate through the intestinal mucus, (3) overcomes the different gastrointestinal barriers, and (4) provides an effective therapeutic dose. Therefore, optimization of oral bioavailability of poorly-soluble drugs still remains a significant challenge for the pharmaceutical industry. Even though numerous conventional drug carriers have successfully solved some of the issues related to oral delivery of poorly-soluble drugs, only few of them met commercialization requirements. These drawbacks have led the scientific world to reconsider its approaches toward targeted drug delivery systems and researchers started looking for alternative vectorized carriers. In this area, nanoparticle-based materials have several significant advantages over free and non-formulated drugs. For example, nanosized porous silica carriers allow for more sustained and controlled drug release or improved oral bioavailability. Thus, in the present review, we will highlight the most important features of nanostructured silica drug carriers, such as particle size, particle shape, surface roughness or surface functionalization, and underline the key advantages of these nanosupports. In particular, this article will discuss recent progress and challenges in the area of mesoporous silica nanocarriers used for oral drug delivery. Additional emphasis will be set on the biological and chemical features of the gastrointestinal tract as well as currently tested nanoformulations and strategies to avoid drug degradation in the gastrointestinal environment.

Tumor Microenvironment Responsive Nanogel for the Combinatorial Antitumor Effect of Chemotherapy and Immunotherapy

A biomimetic nanogel with tumor microenvironment responsive property is developed for the combinatorial antitumor effects of chemotherapy and immunotherapy. Nanogels are formulated with hydroxypropyl-β-cyclodextrin acrylate and two opposite charged chitosan derivatives for entrapping anticancer drug paclitaxel and precisely controlling the pH responsive capability, respectively. The nanogel supported erythrocyte membrane can achieve "nanosponge" property for delivering immunotherapeutic agent interleukin-2 without reducing the bioactivity. By responsively releasing drugs in tumor microenvironment, the nanogels significantly enhanced antitumor activity with improved drug penetration, induction of calreticulin exposure, and increased antitumor immunity. The tumor microenvironment is remodeled by the combination of these drugs in low dosage, as evidenced by the promoted infiltration of immune effector cells and reduction of immunosuppressive factors.