Galactosamine-modified PEG-PLA/TPGS micelles for the oral delivery of curcumin

Naturally sourced amphiphilic peptides as paclitaxel vehicles for breast cancer treatment

The marketed paclitaxel (PTX) formulation Taxol relies on the application of Cremophor EL as a solubilizer. The major drawback of Taxol is its hypersensitivity reactions and a pretreatment of anti-allergic drugs is a necessity. Therefore, developing an efficient and safe delivery vehicle is a solution to increase PTX treatment outcomes with minimal adverse effects. In this work, we prepared the amphiphilic peptides (termed AmP) from soybean proteins using a facile two-step method. AmP could efficiently solubilize PTX by self-assembling into mixed micelles with D-α-tocopherol polyethylene glycol succinate (TPGS), a common pharmaceutical expedient (PTX@TPGS-AmP). The intravenously administrated PTX@TPGS-AmP exhibited a slow clearance (0.24 mL·(min·kg)-1) and an enhanced AUC (41.4 μg.h/mL), manifesting a 3.6-fold increase compared to Taxol. In a murine 4T1 tumor model, PTX@TPGS-AmP displayed a superior antitumor effect over Taxol. Importantly, safety assessment showed a high biocompatibility of AmP and an i.v. dose up to 2500 mg/kg led to no observable abnormalities in the mice. In summary, the AmP presents a new green and easily-prepared amphiphilic biomaterial, with promising potential as a pharmaceutical excipient for drug delivery.

Oral targeted drug delivery to post-gastrointestinal sites

As an essential branch of targeted drug delivery, oral targeted delivery is attracting growing attention in recent years. In addition to site-specific delivery for the treatment of locoregional diseases in the gastrointestinal tract (GIT), oral targeted delivery to remote sites beyond the GIT emerges as a cutting-edge research topic. This review aims to provide an overview of the fundamental concepts and most recent advances in this field. Owing to the physiological barriers existing in the GIT, carrier systems should be transported across the enteric epithelia to target remote sites. Recently, pioneer investigations have validated the transport of intact micro- or nanocarriers across gastrointestinal barriers and subsequently to various distal organs and tissues. The microfold (M) cell pathway is the leading mechanism underlying the oral absorption of particulates, but the contribution of the transcellular and paracellular pathways should not be neglected either. In addition to well-acknowledged physicochemical and biological factors, the formation of a protein corona may also influence the biological fate of carrier systems. Although in an early stage of conceptualization, oral targeted delivery to remote diseases has demonstrated promising potential for the treatment of inflammation, tumors, and diseases inflicting the lymphatic and mononuclear phagocytosis systems.

Synthesis and in vitro antitumor activity of galactosamine-docetaxel conjugates

Docetaxel (DTX) is a semi-synthetic analogue of paclitaxel which has attracted extensive attention in the treatment of cancer. However, the current clinically used DTX formulations display low tumor targeting ability, leading to unsatisfactory therapeutic outcomes with adverse effects, which poses significant challenges to the clinical application. In this study, three galactosamine (Gal) and docetaxel conjugates with different linkers were synthesized, namely DTX-(suc-Gal)2, DTX-(DTDPA-Gal)2, and DTX-(DSeDPA-Gal)2. These three conjugates were characterized by 1H NMR, FT-IR and HRMS. The in vitro drug release study shows that DTX-(DTDPA-Gal)2 and DTX-(DSeDPA-Gal)2 exhibit glutathione (GSH)-responsive drug release and DTX-(DSeDPA-Gal)2 displays higher GSH-responsiveness. The in vitro antitumor activity study shows that DTX-(DTDPA-Gal)2 and DTX-(DSeDPA-Gal)2 exhibit enhanced cytotoxicity, cell apoptosis rate and G2/M phase arrest against HepG2 cells as compared to DTX-(suc-Gal)2, DTX-(DSeDPA-Gal)2 displays the highest cytotoxicity, cell apoptosis rate and G2/M phase arrest among these three conjugates. In addition, DTX-(DSeDPA-Gal)2 exhibits higher selectivity to HepG2 cells as compared to free DTX. The DTX-(DSeDPA-Gal)2 developed in this study has been proven to be an effective DTX conjugate for selective killing hepatoma cells.

Anti-Melanoma Activity of Single Intratumoral Injection of ZnPc Micelles Mixed With in situ Gel in B16 Bearing Mouse

Photodynamic therapy (PDT) is a potential treatment strategy for melanoma. As a second-generation photosensitizer, Zinc phthalocyanine (ZnPc) has many advantages for anti-tumor PDTs, such as strong absorption in the red and near infrared regions, high photo and chemical stability, etc. However, ZnPc has a poor water solubility and is apt to aggregate due to the π-π interaction between molecules, which limits its applications. In this study, various solvents and surfactants were screened for dissolving ZnPc and preparing ZnPc@SDC-TPGS micelle and thermosensitive in situ gel. After the cytotoxic effects of thermosensitive gels on PDT were tested, the antitumor effects on PDT of them in mice by intratumoral injection were evaluated, including body weight, and tumor weight, volume and morphology. The cell death pathway and the relationship of reactive oxygen species yield with apoptotic rate of tumor cells induced by ZnPc in situ gel were investigated. The results were that N-methyl-pyrrolidone (NMP) mixed with 2 % SDC and aqueous solution containing 2 % TPGS and 2 % SDC were used to synthesize ZnPc@SDC-TPGS micelle and the thermosensitive in situ gel. The cytotoxic effects of thermosensitive gels showed good tumor suppression of ZnPc@SDC-TPGS in situ gel and no toxicity of the blank gel. Intratumoral injection in situ gel containing 3 µg ZnPc under irradiation demonstrated good tumor inhibition in mice with melanoma. Apoptosis has been established as the primary pathway of cell death, and the production of reactive oxygen species (ROS) plays a crucial role in cellular apoptosis induced by ZnPc@SDC-TPGS in situ gel. In conclusion, the intratumoral injection of ZnPc@SDC-TPGS thermosensitive in situ gel provides a promising local treatment option for melanoma.

Curcumin-Loaded RH60/F127 Mixed Micelles: Characterization, Biopharmaceutical Characters and Anti-Inflammatory Modulation of Airway Inflammation

Curcumin's ability to impact chronic inflammatory conditions, such as metabolic syndrome and arthritis, has been widely researched; however, its poor bioavailability limits its clinical application. The present study is focused on the development of curcumin-loaded polymeric nanomicelles as a drug delivery system with anti-inflammatory effects. Curcumin was loaded in PEG-60 hydrogenated castor oil and puronic F127 mixed nanomicelles (Cur-RH60/F127-MMs). Cur-RH60/F127-MMs was prepared using the thin film dispersion method. The morphology and releasing characteristics of nanomicelles were evaluated. The uptake and permeability of Cur-RH60/F127-MMs were investigated using RAW264.7 and Caco-2 cells, and their bioavailability and in vivo/vitro anti-inflammatory activity were also evaluated. The results showed that Cur-RH60/F127-MMs have regular sphericity, possess an average diameter smaller than 20 nm, and high encapsulation efficiency for curcumin (89.43%). Cur-RH60/F127-MMs significantly increased the cumulative release of curcumin in vitro and uptake by cells (p < 0.01). The oral bioavailability of Cur-RH60/F127-MMs was much higher than that of curcumin-active pharmaceutical ingredients (Cur-API) (about 9.24-fold). The treatment of cell lines with Cur-RH60/F127-MMs exerted a significantly stronger anti-inflammatory effect compared to Cur-API. In addition, Cur-RH60/F127-MMs significantly reduced OVA-induced airway hyperresponsiveness and inflammation in an in vivo experimental asthma model. In conclusion, this study reveals the possibility of formulating a new drug delivery system for curcumin, in particular nanosized micellar aqueous dispersion, which could be considered a perspective platform for the application of curcumin in inflammatory diseases of the airways.

Recent Advances in Nanotechnology-Based Targeted Delivery Systems of Active Constituents in Natural Medicines for Cancer Treatment

Owing to high efficacy and safety, natural medicines have found their way into the field of cancer therapy over the past few decades. However, the effective ingredients of natural medicines have shortcomings of poor solubility and low bioavailability. Nanoparticles can not only solve the problems above but also have outstanding targeting ability. Targeting preparations can be classified into three levels, which are target tissues, cells, and organelles. On the premise of clarifying the therapeutic purpose of drugs, one or more targeting methods can be selected to achieve more accurate drug delivery and consequently to improve the anti-tumor effects of drugs and reduce toxicity and side effects. The aim of this review is to summarize the research status of natural medicines' nano-preparations in tumor-targeting therapies to provide some references for further accurate and effective cancer treatments.

Synthesis of a light-responsive platinum curcumin complex, chemical and biological investigations and delivery to tumor cells by means of polymeric nanoparticles

Platinum-based anticancer drugs are common in chemotherapy, but problems such as systemic toxicity and acquired resistance of some tumors hamper their clinical applications and therapeutic efficacy. It is necessary to synthesize Pt-based drugs and explore strategies to reduce side effects and improve pharmacokinetic profiles. Photo-responsive chemotherapeutics have emerged as an alternative strategy against several cancers, as photoactivation offers spatial selectivity and fewer side effects. Here, we combine chemical synthesis and nanotechnology to create a multifunctional platinum drug delivery system based on the novel metal complex [Pt(ppy)(curc)] (ppy = deprotonated 2-phenylpyridine, curc = deprotonated curcumin)] embodying the naturally occurring bioactive molecule, curcumin. The ultrasonication method coupled with the layer-by-layer technology was employed to produce nanocolloids, which demonstrated a good biocompatibility, higher solubility in aqueous solution, stability, large drug loading, and good biological activity in comparison with the free drug. In vitro release experiments revealed that the polymeric nanoformulation is relatively stable under physiological conditions (pH = 7.4 and 37 °C) but sensitive to acidic environments (pH = 5.6 and 37 °C) which would trigger the release of the loaded drug. Our approach modifies the bioavailability of this Pt-based drug increasing its therapeutic action in terms of both cytotoxic and anti-metastasis effects.

Curcumin nanocrystals self-stabilized Pickering emulsion freeze-dried powder: Development, characterization, and suppression of airway inflammation

Curcumin, a diketone compound extracted from turmeric's rhizome, is an effective anti-inflammatory drug with multiple pharmacological activities. However, its low oral bioavailability due to its low water solubility and permeability severely limits its clinical applications. Therefore, to enhance the oral bioavailability of curcumin, further enhance its anti-inflammatory effects, and improve its potential in the treatment of airway inflammation, a curcumin nanocrystalline self-stabilizing Pickering emulsion (Cur-NSSPE) was prepared through high-pressure homogenization. Next, Cur-NSSPE was dried using a freeze-drying method to produce Cur-NSSPE-FDP. The prepared Cur-NSSPE and Cur-NSSPE-FDP were physically characterized. The release behavior and transmembrane transport capability of Cur-NSSPE-FDP in vitro were evaluated. Pharmacokinetic study was performed to evaluate its oral bioavailability. The anti-inflammatory effects of Cur-NSSPE-FDP in vivo and in vitro were investigated using RAW 264.7 macrophage inflammation model induced by LPS and IFN-γ and asthma model in BALB/c mice induced by OVA. The average particle size of Cur-NSSPE was (163.66 ± 6.78) nm, and the average drug content was (2.78 ± 0.01) mg/mL. The transmission electron microscopy results showed that the droplets were spherical in shape with a relatively uniform size, and the curcumin nanocrystals formed a spherical core-shell structure wrapped at the interface of the droplets. The scanning electron microscopy showed that Cur-NSSPE-FDP was a neatly arranged, having loose and porous network structure. Furthermore, it can significantly improve the cumulative release of curcumin in vitro and improve oral bioavailability in rats, increase the uptake of RAW264.7 and Caco-2 cells, promote the transport of curcumin across Caco-2 cells, significantly inhibit the expression of inflammatory factors NO, IL-6, TNF-a, MDA, IgE and ICAM-1, and improve the expression of IL-10 and SOD. These results indicated that the curcumin nanocrystalline self-stabilizing Pickering emulsion-freeze dried powder improved the oral bioavailability of curcumin and enhanced its therapeutic effect in airway inflammation.

Curcumin in the treatment of liver cancer: From mechanisms of action to nanoformulations

Liver cancer is the sixth most prevalent cancer and ranks third in cancer-related death, after lung and colorectal cancer. Various natural products have been discovered as alternatives to conventional cancer therapy strategies, including radiotherapy, chemotherapy, and surgery. Curcumin (CUR) with antiinflammatory, antioxidant, and antitumor activities has been associated with therapeutic benefits against various cancers. It can regulate multiple signaling pathways, such as PI3K/Akt, Wnt/β-catenin, JAK/STAT, p53, MAPKs, and NF-ĸB, which are involved in cancer cell proliferation, metastasis, apoptosis, angiogenesis, and autophagy. Due to its rapid metabolism, poor oral bioavailability, and low solubility in water, CUR application in clinical practices is restricted. To overcome these limitations, nanotechnology-based delivery systems have been applied to use CUR nanoformulations with added benefits, such as reducing toxicity, improving cellular uptake, and targeting tumor sites. Besides the anticancer activities of CUR in combating various cancers, especially liver cancer, here we focused on the CUR nanoformulations, such as micelles, liposomes, polymeric, metal, and solid lipid nanoparticles, and others, in the treatment of liver cancer.

Crizotinib loaded polydopamine-polylactide-TPGS nanoparticles in targeted therapy for non-small cell lung cancer

To evaluate the effect and safety of crizotinib loaded polydopamine-polylactide-TPGS nanoparticles (CZT/pD-PT NPs) on non-small cell lung cancer (NSCLC). CZT/pD-PT NPs were synthesized and characterized, and their effects on PC-9 cell viability and apoptosis were determined. In vivo experiment was further performed to evaluate the anti-NSCLC efficacy of CZT/pD-PT NPs. TUNEL assay and Western blot were respectively applied for the determination of cell apoptosis and apoptosis-related protein expression, while liver function-related index expression detection and liver histopathological detection were used to evaluate the hepatotoxicity of CZT/pD-PT NPs. Compared with free CZT, CZT/pD-PT NPs had a sustained-release effect and promoted the cellular uptake of CZT. In addition, CZT/pD-PT NPs significantly inhibited PC-9 cell viability and promoted cell apoptosis both in vitro and in vivo, exhibiting superior cytotoxicity. At the same time, CZT/pD-PT NPs had no significant effect on liver tissue morphology and liver function-related indicators such as ALP, ALT, AST, and DBIL. CZT/pD-PT NPs have excellent anti-NSCLC effect with low hepatotoxicity, which can be served as a novel drug delivery system to improve the efficacy of chemotherapy for NSCLC.

Biomaterials and Extracellular Vesicle Delivery: Current Status, Applications and Challenges

In this review, we will discuss the current status of extracellular vesicle (EV) delivery via biopolymeric scaffolds for therapeutic applications and the challenges associated with the development of these functionalized scaffolds. EVs are cell-derived membranous structures and are involved in many physiological processes. Naïve and engineered EVs have much therapeutic potential, but proper delivery systems are required to prevent non-specific and off-target effects. Targeted and site-specific delivery using polymeric scaffolds can address these limitations. EV delivery with scaffolds has shown improvements in tissue remodeling, wound healing, bone healing, immunomodulation, and vascular performance. Thus, EV delivery via biopolymeric scaffolds is becoming an increasingly popular approach to tissue engineering. Although there are many types of natural and synthetic biopolymers, the overarching goal for many tissue engineers is to utilize biopolymers to restore defects and function as well as support host regeneration. Functionalizing biopolymers by incorporating EVs works toward this goal. Throughout this review, we will characterize extracellular vesicles, examine various biopolymers as a vehicle for EV delivery for therapeutic purposes, potential mechanisms by which EVs exert their effects, EV delivery for tissue repair and immunomodulation, and the challenges associated with the use of EVs in scaffolds.

Orally Administered Halofuginone-Loaded TPGS Polymeric Micelles Against Triple-Negative Breast Cancer: Enhanced Absorption and Efficacy with Reduced Toxicity and Metastasis

Background

Halofuginone (HF)-loaded TPGS polymeric micelles (HTPM) were successfully fabricated using the thin-film hydration technique. HTPM via intravenous injection have been demonstrated to exert an excellent anticancer effect against triple-negative breast cancer (TNBC) cells and subcutaneous xenografts. In the present study, we further explored the potential treatment effect and mechanism of orally administered HTPM alone and in combination with surgical therapy on TNBC in subcutaneous and orthotopic mouse models.

Methods

Herein, the stability and in vitro release behavior of HTPM were first evaluated in the simulated gastrointestinal fluids. Caco-2 cell monolayers were then used to investigate the absorption and transport patterns of HF with/without encapsulation in TPGS polymeric micelles. Subsequently, the therapeutic effect of orally administered HTPM was checked on subcutaneous xenografts of TNBC in nude mice. Ultimately, orally administered HTPM, combined with surgical therapy, were utilized to treat orthotopic TNBC in nude mice.

Results

Our data confirmed that HTPM exhibited good stability and sustained release in the simulated gastrointestinal fluids. HF was authenticated to be a substrate of P-glycoprotein (P-gp), and its permeability across Caco-2 cell monolayers was markedly enhanced via heightening intracellular absorption and inhibiting P-gp efflux due to encapsulation in TPGS polymeric micelles. Compared with HF alone, HTPM showed stronger tumor-suppressing effects in subcutaneous xenografts of MDA-MB-231 cells when orally administered. Moreover, compared with HTPM or surgical therapy alone, peroral HTPM combined with partial surgical excision synergistically retarded the growth of orthotopic TNBC. Fundamentally, HTPM orally administered at the therapeutic dose did not cause any pathological injury, while HF alone led to weight loss and jejunal bleeding in the investigated mice.

Conclusion

Taken together, HTPM could be applied as a potential anticancer agent for TNBC by oral administration.

Improved solubility and corneal permeation of PEGylated curcumin complex used for the treatment of ophthalmic bacterial infections

Naturally occurring curcumin can be used for the treatment of corneal bacterial infections with its limitation of poor solubility. Aim of the present study was to enhance solubility and permeation of curcumin for the treatment of corneal bacterial infections. For increasing solubility, curcumin and polyethylene glycol (PEG 6000) complex (1:3) was prepared by fusion melting method. Phase solubility studies were used for the calculation of Gibbs free energy of curcumin. Central composite rotatable design (CCRD) was applied for optimization of Curcumin (CUR), PEGylated Curcumin (PEG-CUR), penetration enhancer cremophore (CR). Optimized ointments were further evaluated by mucous permeation, membrane permeability and cell toxicity studies by Transwell cell, ussing chamber and Caco-2 cells respectively. Antibacterial test was also performed by agar well diffusion method. Solubility of PEG-CUR was increased up to 93±3.2% as compared to pure curcumin and content uniformity was in the range of 95–110%. Curcumin permeation from PEG-CUR ointment was increased up to 12 folds. No toxicity of Caco-2 cells for PEG-CUR even after 24h was observed. Activity index of pure CUR, PEG-CUR ointment with or without CR against S. aureus and P. aeruginosa was 97±2.3, 96±1.6, 95±2.5% respectively. Ointment with solubility enhanced PEG-CUR and cremophore can be used as a promising tool for the treatment of corneal bacterial infections.

No Solid Colloidal Carriers: Aspects Thermodynamic the Immobilization Chitinase and Laminarinase in Liposome

The present review describes the basic properties of colloidal and vesicular vehicles that can be used for immobilization of enzymes. The thermodynamic aspects of the immobilization of enzymes (laminarinase and chitinase) in liposomes are discussed. These systems protect enzymes against environmental stress and allow for a controlled and targeted release. The diversity of colloidal and vesicular carriers allows the use of enzymes for different purposes, such as mycolytic enzymes used to control phytopathogenic fungi.

Curcumin-based ionic Pt(ii) complexes: antioxidant and antimicrobial activity

Four new Pt(ii) ionic complexes assembled from N-donor ligands and curcumin display interesting antioxidant and antimicrobial properties.

Drug Delivery Strategies for Curcumin and Other Natural Nrf2 Modulators of Oxidative Stress-Related Diseases

Oxidative stress is associated with a wide range of diseases characterised by oxidant-mediated disturbances of various signalling pathways and cellular damage. The only effective strategy for the prevention of cellular damage is to limit the production of oxidants and support their efficient removal. The implication of the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway in the cellular redox status has spurred new interest in the use of its natural modulators (e.g., curcumin, resveratrol). Unfortunately, most natural Nrf2 modulators are poorly soluble and show extensive pre-systemic metabolism, low oral bioavailability, and rapid elimination, which necessitates formulation strategies to circumvent these limitations. This paper provides a brief introduction on the cellular and molecular mechanisms involved in Nrf2 modulation and an overview of commonly studied formulations for the improvement of oral bioavailability and in vivo pharmacokinetics of Nrf2 modulators. Some formulations that have also been studied in vivo are discussed, including solid dispersions, self-microemulsifying drug delivery systems, and nanotechnology approaches, such as polymeric and solid lipid nanoparticles, nanocrystals, and micelles. Lastly, brief considerations of nano drug delivery systems for the delivery of Nrf2 modulators to the brain, are provided. The literature reviewed shows that the formulations discussed can provide various improvements to the bioavailability and pharmacokinetics of natural Nrf2 modulators. This has been demonstrated in animal models and clinical studies, thereby increasing the potential for the translation of natural Nrf2 modulators into clinical practice.

N-trimethyl chitosan coated nano-complexes enhance the oral bioavailability and chemotherapeutic effects of gemcitabine

N-trimethyl chitosan (TMC) is a multifunctional polymer that can be used in various nanoparticle forms in the pharmaceutical, nutraceutical and biomedical fields. In this study, TMC was used as a mucoadhesive adjuvant to enhance the oral bioavailability and hence antitumour effects of gemcitabine formulated into nanocomplexes composed of poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) conjugated with d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). A central composite design was applied to achieve the optimal formulation. Cellular uptake and drug transportation studies revealed the nanocomplexes permeate over the intestinal cells via adsorptive-mediated and caveolae-mediated endocytosis. Pharmacokinetic studies demonstrated the oral drug bioavailability of the nanocomplexes was increased 5.1-fold compared with drug solution. In pharmacodynamic studies, the formulation reduced tumour size 3.1-fold compared with the drug solution. The data demonstrates that TMC modified nanocomplexes can enhance gemcitabine oral bioavailability and promote the anticancer efficacy.

Poly(lactic Acid): A Versatile Biobased Polymer for the Future with Multifunctional Properties-From Monomer Synthesis, Polymerization Techniques and Molecular Weight Increase to PLA Applications

Environmental problems, such as global warming and plastic pollution have forced researchers to investigate alternatives for conventional plastics. Poly(lactic acid) (PLA), one of the well-known eco-friendly biodegradables and biobased polyesters, has been studied extensively and is considered to be a promising substitute to petroleum-based polymers. This review gives an inclusive overview of the current research of lactic acid and lactide dimer techniques along with the production of PLA from its monomers. Melt polycondensation as well as ring opening polymerization techniques are discussed, and the effect of various catalysts and polymerization conditions is thoroughly presented. Reaction mechanisms are also reviewed. However, due to the competitive decomposition reactions, in the most cases low or medium molecular weight (MW) of PLA, not exceeding 20,000-50,000 g/mol, are prepared. For this reason, additional procedures such as solid state polycondensation (SSP) and chain extension (CE) reaching MW ranging from 80,000 up to 250,000 g/mol are extensively investigated here. Lastly, numerous practical applications of PLA in various fields of industry, technical challenges and limitations of PLA use as well as its future perspectives are also reported in this review.