Therapeutic Effects of Curcumin Liposomes and Nanocrystals on Inflammatory Osteolysis: In Vitro and In Vivo Comparative Study

Percutaneous Delivery of Hederacoside C-Loaded Nanoliposome Gel Alleviates Psoriasiform Skin Inflammation through the CCL17/Treg Axis

Psoriasis is a chronic, recurrent, and inflammatory skin disease. Topical agents, which can avoid the adverse effects of systemic treatment, are the first-choice therapy for patients with mild-to-moderate psoriasis. Hederacoside C (HSC) with anti-inflammatory properties has been used to treat some inflammatory diseases. We speculated that HSC might also be effective for psoriasis treatment. However, topical application of HSC for psoriasis treatment is challenging because of its low water solubility and poor skin permeability. Therefore, it is important to effectively deliver HSC percutaneously using certain biomaterials. Here we constructed a hydroxypropyl-β-cyclodextrin-coated liposome gel formulation for the loading and percutaneously delivering of HSC, referred to as HSC-Lipo@gel. The characterization, stability, release properties, and mechanical or transdermal features of the HSC-Lipo@gel were evaluated. Its therapeutic potential was also demonstrated using mouse models of IMQ-induced psoriasis. We found that HSC-Lipo@gel effectively improved the skin permeability of HSC with the property of good stability and sustained release. Importantly, HSC-Lipo@gel showed higher efficacy than HSC@gel without liposomes in alleviating psoriatic skin lesions. It attenuated epidermal hyperplasia and suppressed expression of IL-17A, TNF-α, IL-6, and IL-23 in lesional skin. Interestingly, HSC-Lipo@gel reduced the expression of CC chemokine ligand 17 (CCL17), but not CCL22, in the skin. Especially, HSC-Lipo@gel inhibited CCL17 expression by skin dendritic cells while increasing regulatory T cells (Tregs) in both skin and draining lymph nodes of psoriatic mice. Administration of CCL17 resulted in severe skin lesions and reduced CD4+FoxP3+ Tregs in psoriatic mice previously treated with HSC-Lipo@gel. Finally, HSC or HSC-Lipo also suppressed the CCL17 production by dendritic cells in vitro. Therefore, HSC-Lipo@gel alleviated psoriasiform skin inflammation by increasing cutaneous Tregs via downregulation of the expression of CCL17, but not CCL22. Thus, HSC-Lipo@gel may be a stable, highly permeable, and effective system for topical treatment of psoriasis.

Curcuma Longa: Nutraceutical Use and Association With Nanotechnology

Curcumin is a natural product found in the rhizome of Curcuma longa (L.) and other Curcuma spp. As a lipophilic molecule, it has greater affinity for polar, non-polar, alkaline, or extremely acidic organic solvents. Several studies indicate that curcumin has several benefits for human health, for example, against degenerative diseases, cancer, and infectious diseases. To obtain a quality product with nutraceutical properties, it is necessary to know its physicochemical characteristics and preserve it from cultivation until ingestion by the human. However, its low solubility leads to low absorption; in this context, nanotechnological systems can contribute to increase curcumin bioavailability. This review aims to highlight important issues in all stages that curcumin goes through: from aspects related to its extraction to its association with nanotechnology. Although curcumin extraction process is already well established, it is possible to observe more and more research focused on increasing yield and being more environmentally friendly. Further, curcumin's low absorption is notable due to its physicochemical characteristics, mainly due to its low aqueous solubility. However, its association with nanotechnology shows to be promising and an increasingly growing trend because the use of this "Indian solid gold" is the hope of many patients.

Curcumin nanopreparations: recent advance in preparation and application

Curcumin is a natural polyphenolic compound extracted from turmeric with antibacterial, antioxidant, antitumor, preventive and therapeutic neurological disorders and a variety of bioactivities, which is widely used in the field of food and medicine. However, the drawbacks of curcumin such as poor aqueous solubility and stability have limited the practical application of curcumin. To overcome these defects and enhance its functional properties, various nanoscale systems (liposomes, polymer nanoparticles, protein nanoparticles, solid lipid nanoparticles, metal nanoparticles, etc) have been extensively employed for curcumin encapsulation and delivery. Despite the rapid development of curcumin nanoformulations, there is a lack of comprehensive reviews on their preparation and properties. This review provides an overview of the construction of curcumin nano-delivery systems, mechanisms of action, nanocarrier preparation methods and the applications of curcumin nanocarriers in the food and pharmaceutical fields to provide a theoretical basis and technological support for the efficient bio-utilization, product development and early clinical application of curcumin.

Enhanced Dissolution and Bioavailability of Curcumin Nanocrystals Prepared by Hot Melt Extrusion Technology

Purpose

Curcumin nanocrystals (Cur-NCs) were prepared by hot melt extrusion (HME) technology to improve the dissolution and bioavailability of curcumin (Cur).

Methods

Cur-NCs with different drug-carrier ratios were prepared by one-step extrusion process with Eudragit® EPO (EEP) as the carrier. The dispersed size and solid state of Cur in extruded samples were characterized by dynamic light scattering (DLS), scanning electron microscope (SEM), differential scanning calorimetry (DSC), and X-ray diffraction (XRD). The thermal stability of Cur was analyzed by thermogravimetric analysis (TGA) and high performance liquid chromatography (HPLC). Dissolution and pharmacokinetics were studied to evaluate the improvement of dissolution and absorption of Cur by nano-preparation.

Results

Cur-NCs with particle sizes in the range of 50~150 nm were successfully prepared by using drug-carrier ratios of 1:1, 2:1 and 4:1, and the crystal form of Cur was Form 1 both before and after HME. The extrudate powders showed very efficient dissolution with the cumulative dissolution percentage of 80% in less than 2 min, and the intrinsic dissolution rates of them were 13.68 ± 1.20 mg/min/cm2, 11.78 ± 0.57 mg/min/cm2 and 4.35 ± 0.20 mg/min/cm2, respectively, whereas that of pure Cur was only 0.04 ± 0.00 mg/min/cm2. The TGA data demonstrated that the degradation temperature of Cur was about 250 °C, while the HPLC results showed Cur was degraded when extruded at the temperature over 150 °C. Pharmacokinetic experiment showed a significant improvement in the absorption of Cur. The Cmax of Cur in the Cur-NC group was 1.68 times that of pure Cur group, and the Cmax and area under the curve (AUC0-∞) of metabolites were 2.79 and 4.07 times compared with pure Cur group.

Conclusion

Cur-NCs can be prepared by HME technology in one step, which significantly improves the dissolution and bioavailability of Cur. Such a novel method for preparing insoluble drug nanocrystals has broad application prospects.

Nanocrystals and nanosuspensions: an exploration from classic formulations to advanced drug delivery systems

Nanocrystals and nanosuspensions have become realistic approaches to overcome the formulation challenges of poorly water-soluble drugs. They also represent a less-known but versatile platform for multiple therapeutic applications. They can be integrated into a broad spectrum of drug delivery systems including tablets, hydrogels, microneedles, microparticles, or even functionalized liposomes. The recent progresses, challenges, and opportunities in this field are gathered originally together with an informative case study concerning an itraconazole nanosuspension-in-hydrogel formulation. The translational aspects, historical and current clinical perspectives are also critically reviewed here to shed light on the incoming generation of nanocrystal formulations.

Macrophage-related therapeutic strategies: Regulation of phenotypic switching and construction of drug delivery systems

Macrophages, as highly phenotypic plastic immune cells, play diverse roles in different pathological conditions. Changing and controlling the phenotypes of macrophages is considered a novel potential therapeutic intervention. Meanwhile, specific transmembrane proteins anchoring on the surface of the macrophage membrane are relatively conserved, supporting its functional properties, such as inflammatory chemotaxis and tumor targeting. Thus, a series of drug delivery systems related to specific macrophage membrane proteins are commonly used to treat chronic inflammatory diseases. This review summarizes macrophages-based strategies for chronic diseases, discusses the regulation of macrophage phenotypes and their polarization processes, and presents how to design and apply the site-specific targeted drug delivery systems in vivo based on the macrophages and their derived membrane receptors. It aims to provide a better understanding of macrophages in immunoregulation and proposes macrophages-based targeted therapeutic approaches for chronic diseases.

Synthesis, optimization via response surface methodology, and structural properties of carboxymethylcellulose/curcumin/graphene oxide biocomposite films/coatings for the shelf-life extension of shrimp

In this study, carboxymethylcellulose (CMC), curcumin (Cur), and graphene oxide (GO) were used to prepare a novel biocomposite film (CMC-Cur-GO). A central composite design under response surface methodology was employed to optimize the films in terms of water vapor permeability (WVP) and swelling percentage (SP). Under the optimum conditions, which the rates of CMC, GO and curcumin were found to be 1350 mg, 29.99 mg, and 0.302 g, respectively, WVP and SP of CMC-Cur-GO were obtained 0.902 × 10-8 (g/m·h·Pa) and 13.62 %, respectively. The biocomposite films (CMC, CMC-Cur, CMC-GO and CMC-Cur-GO) were characterized by Fourier transform infrared spectroscopy, field-emission scanning electron microscope, thermal gravimetric analysis, X-ray diffraction analysis, ultraviolet-vis light transmittance, moisture content, and mechanical properties. Compared with pure CMC film, the tensile strength, elongation at break and Young's modulus of CMC-Cur-GO were significantly improved by up to 75 %, 41 % and 23 %, respectively (p < 0.05). Then, CMC-Cur-GO was applied as a coating solution for the shrimps. The coated shrimps with the CMC-Cur-GO significantly (p < 0.05) showed a noteworthy improvement in microbial quality (total and psychrotrophic bacterial count), chemical deterioration and lipid oxidation (pH and total volatile basic nitrogen, peroxide value and thiobarbituric acid) and physical characteristic (weight loss) as compared to other samples. The CMC-Cur-GO coating could increase the shelf life of shrimp under refrigerated storage.

Enhancing Transdermal Delivery of Curcumin-Based Ionic Liquid Liposomes for Application in Psoriasis

To improve the permeation of curcumin, we prepared curcumin-based ionic liquid (Cur-Bet-IL) (IL formed using curcumin succinic anhydride and betaine) from curcumin by combining theoretical calculation and experimental research and then prepared curcumin-based ionic liquid liposome (Cur-Bet-IL-Lip). The Cur-Bet-IL-Lip has good stability (stored for 10 days without significant changes) and biocompatibility, which encompasses not only the properties of curcumin but also the characteristics of ionic liquids and liposomes. Cur-Bet-IL-Lip can penetrate the stratum corneum and deliver curcumin to the epidermis and dermis of the skin, and the cumulative permeability of curcumin after 24 h was 49%. Compared to Cur-Bet-IL, Cur-Bet-IL-Lip has a good uptake ability on human immortalized keratinocyte (HaCaT) cells (1.87-fold), which can reduce the expression of TNF-α (1.59-fold), IL-1β (1.19-fold), IL-17A (1.53-fold), IL-17F (1.18-fold), and IL-22 (1.49-fold) in HaCaT cells and then increase the expression of collagen-I (1.14-fold). Therefore, Cur-Bet-IL-Lip has guiding significance in improving the solubility and permeation of insoluble drugs, which also provides a potential value for the clinical application of curcumin.

Targeting different phenotypes of macrophages: A potential strategy for natural products to treat inflammatory bone and joint diseases

BACKGROUND

Macrophages, a key class of immune cells, have a dual role in inflammatory responses, switching between anti-inflammatory M2 and pro-inflammatory M1 subtypes depending on the specific environment. Greater numbers of M1 macrophages correlate with increased production of inflammatory chemicals, decreased osteogenic potential, and eventually bone and joint disorders. Therefore, reversing M1 macrophages polarization is advantageous for lowering inflammatory factors. To better treat inflammatory bone disorders in the future, it may be helpful to gain insight into the specific mechanisms and natural products that modulate macrophage polarization.

OBJECTIVE

This review examines the impact of programmed cell death and different cells in the bone microenvironment on macrophage polarization, as well as the effects of natural products on the various phenotypes of macrophages, in order to suggest some possibilities for the treatment of inflammatory osteoarthritic disorders.

METHODS

Using 'macrophage polarization,' 'M1 macrophage' 'M2 macrophage' 'osteoporosis,' 'osteonecrosis of femoral head,' 'osteolysis,' 'gouty arthritis,' 'collagen-induced arthritis,' 'freund's adjuvant-induced arthritis,' 'adjuvant arthritis,' and 'rheumatoid arthritis' as search terms, the relevant literature was searched using the PubMed, the Cochrane Library and Web of Science databases.

RESULTS

Targeting macrophages through different signaling pathways has become a key mechanism for the treatment of inflammatory bone and joint diseases, including HIF-1α, NF-κB, AKT/mTOR, JAK1/2-STAT1, NF-κB, JNK, ERK, p-38α/β, p38/MAPK, PI3K/AKT, AMPK, AMPK/Sirt1, STAT TLR4/NF-κB, TLR4/NLRP3, NAMPT pathway, as well as the programmed cell death autophagy, pyroptosis and ERS.

CONCLUSION

As a result of a search of databases, we have summarized the available experimental and clinical evidence supporting herbal products as potential treatment agents for inflammatory osteoarthropathy. In this paper, we outline the various modulatory effects of natural substances targeting macrophages in various diseases, which may provide insight into drug options and directions for future clinical trials. In spite of this, more mechanistic studies on natural substances, as well as pharmacological, toxicological, and clinical studies are required.