Development of a new class of sulforaphane-enabled self-emulsifying drug delivery systems (SFN-SEDDS) by high throughput screening: A case study with curcumin

Fabrication of controlled-release polymeric microneedles containing progesterone-loaded self-microemulsions for transdermal delivery

Progesterone (PG) has been approved for hormone replacement therapy to mitigate the risk of endometrial carcinoma. However, there has been a lack of success in oral PG due to its rapid degradation. Transdermal PG has advantages but lacks efficacy due to its poor solubility (Log p = 3.9). Therefore, this study aimed to evaluate how combining self-microemulsifying drug delivery systems (SMEDDS) and polymeric microneedles (MNs) could improve the transdermal delivery of PG in a controlled-release manner. Among PG-SMEDDS, PG-SME5 was selected for its desirable properties and stability. The two-layer polymeric MNs formulation incorporating PG-SME5 (PG-SMEDDS-tMNs) was formulated from aqueous blends of polymers as a first layer and 20% PCL as a second layer. It successfully penetrated neonatal porcine skin with the dissolution of the first layer observed within 15 min after application. In vitro skin permeation revealed that the percentage of PG which permeated the skin over 82 h using PG-SMEDDS-tMNs was higher than a PG-suspension and PG-SMEDDS. The Higuchi kinetic showed controlled release over 15 days of PG from PG-SMEDDS-tMNs. These studies suggested that incorporating PG-SMEDDS into controlled-release two-layer polymeric MNs could be a promising approach for improving the transdermal delivery of PG.

Self-Emulsifying Systems for Delivery of Bioactive Compounds from Natural Origin

Nature has been used as therapeutic resources in the treatment of diseases for many years. However, some natural compounds have poor water solubility. Therefore, physicochemical strategies and technologies are necessary for development of systems for carrying these substances. The self-emulsifying drug delivery systems (SEDDS) have been used as carriers of hydrophobic compounds in order to increase the solubility and absorption, improving their bioavailability. SEDDS are constituted with a mixture of oils and surfactants which, when come into contact with an aqueous medium under mild agitation, can form emulsions. In the last years, a wide variety of self-emulsifying formulations containing bioactive compounds from natural origin has been developed. This review provides a comprehensive overview of the main excipients and natural bioactive compounds composing SEDDS. In addition, applications, new technologies and innovation are reviewed as well. Examples of self-emulsifying formulations administered in different sites are also considered for a better understanding of the use of this strategy to modify the delivery of compounds from natural origin.

Sustained release of curcumin self-emulsifying drug delivery system (SEDDS) from solvent-cast Soluplus® films

The objective of the present study was to investigate the feasibility of formulating and loading Curcumin SEDDS (Self-Emulsified Drug Delivery Systems) into films made from Soluplus^® as the film-forming polymer. Films with up to 30% of Curcumin SEDDS were prepared by the solvent casting technique and analyzed for their mechanical and dissolution properties. A nine-run, two-factor, three-level factorial design was utilized to investigate the effect of SEDDS load (10, 20, and 30% w/w) and film thickness (10, 25, and 40 mils) on the tensile strength, elongation, and adhesiveness of the films. The dissolution profile of the films was also investigated by a USP Type 1 method. SEDDS loading was found to plasticize Soluplus^® and to yield transparent films of good mechanical properties. Increasing SEDDS load, however, was found to reduce the tensile strength of the films, while increasing their adhesiveness and elongation. On the other hand, while an increase in film thickness was found to increase the tensile strength of the films, it reduced the elongation capacity of the films. Loading SEDDS into Soluplus^® films was also found to sustain their release over 6 h, where a significant delay in release was found at lower SEDDS loads. This study demonstrated that Soluplus^® can be used not only to formulate SEDDS into polymeric films but also to sustain their release over an extended time.

Nanocurcumin-Loaded UCNPs for Cancer Theranostics: Physicochemical Properties, In Vitro Toxicity, and In Vivo Imaging Studies

Formulation of promising anticancer herbal drug curcumin as a nanoscale-sized curcumin (nanocurcumin) improved its delivery to cells and organisms both in vitro and in vivo. We report on coupling nanocurcumin with upconversion nanoparticles (UCNPs) using Poly (lactic-co-glycolic Acid) (PLGA) to endow visualisation in the near-infrared transparency window. Nanocurcumin was prepared by solvent-antisolvent method. NaYF4:Yb,Er (UCNP1) and NaYF4:Yb,Tm (UCNP2) nanoparticles were synthesised by reverse microemulsion method and then functionalized it with PLGA to form UCNP-PLGA nanocarrier followed up by loading with the solvent-antisolvent process synthesized herbal nanocurcumin. The UCNP samples were extensively characterised with XRD, Raman, FTIR, DSC, TGA, UV-VIS-NIR spectrophotometer, Upconversion spectrofluorometer, HRSEM, EDAX and Zeta Potential analyses. UCNP1-PLGA-nanocurcumin exhibited emission at 520, 540, 660 nm and UCNP2-PLGA-nanocurmin showed emission at 480 and 800 nm spectral bands. UCNP-PLGA-nanocurcumin incubated with rat glioblastoma cells demonstrated moderate cytotoxicity, 60-80% cell viability at 0.12-0.02 mg/mL marginally suitable for therapeutic applications. The cytotoxicity of UCNPs evaluated in tumour spheroids models confirmed UCNP-PLGA-nanocurcumin therapeutic potential. As-synthesised curcumin-loaded nanocomplexes were administered in tumour-bearing laboratory animals (Lewis lung cancer model) and showed adequate contrast to enable in vivo and ex vivo study of UCNP-PLGA-nanocurcumin bio distribution in organs, with dominant distribution in the liver and lungs. Our studies demonstrate promise of nanocurcumin-loaded upconversion nanoparticles for theranostics applications.

Curcumin in cancer therapy: A novel adjunct for combination chemotherapy with paclitaxel and alleviation of its adverse effects

Dealing with cancer is of importance due to enhanced incidence rate of this life-threatening disorder. Chemotherapy is an ideal candidate in overcoming and eradication of cancer. To date, various chemotherapeutic agents have been applied in cancer therapy and paclitaxel (PTX) is one of them. PTX is a key member of taxane family with potential anti-tumor activity against different cancers. Notably, PTX has demonstrated excellent proficiency in elimination of cancer in clinical trials. This chemotherapeutic agent is isolated from Taxus brevifolia, and is a tricyclic diterpenoid. However, resistance of cancer cells into PTX chemotherapy has endangered its efficacy. Besides, administration of PTX is associated with a number of side effects such as neurotoxicity, hepatotoxicity, cardiotoxicity and so on, demanding novel strategies in obviating PTX issues. Curcumin is a pharmacological compound with diverse therapeutic effects including anti-tumor, anti-oxidant, anti-inflammatory, anti-diabetic and so on. In the current review, we demonstrate that curcumin, a naturally occurring nutraceutical compound is able to enhance anti-tumor activity of PTX against different cancers. Besides, curcumin administration reduces adverse effects of PTX due to its excellent pharmacological activities. These topics are discussed with an emphasis on molecular pathways to provide direction for further studies in revealing other signaling networks.

Development of Topical/Transdermal Self-Emulsifying Drug Delivery Systems, Not as Simple as Expected

Self-emulsifying drug delivery systems (SEDDSs) originated as an oral lipid-based drug delivery system with the sole purpose of improving delivery of highly lipophilic drugs. However, the revolutionary drug delivery possibilities presented by these uniquely simplified systems in terms of muco-adhesiveness and zeta-potential changing capacity lead the way forward to ground-breaking research. Contrarily, SEDDSs destined for topical/transdermal drug delivery have received limited attention. Therefore, this review is focused at utilising principles, established during development of oral SEDDSs, and tailoring them to fit evaluation strategies for an optimised topical/transdermal drug delivery vehicle. This includes a detailed discussion of how the authentic pseudo-ternary phase diagram is employed to predict phase behaviour to find the self-emulsification region most suitable for formulating topical/transdermal SEDDSs. Additionally, special attention is given to the manner of characterising oral SEDDSs compared to topical/transdermal SEDDSs, since absorption within the gastrointestinal tract and the multi-layered nature of the skin are two completely diverse drug delivery territories. Despite the advantages of the topical/transdermal drug administration route, certain challenges such as the relatively undiscovered field of skin metabolomics as well as the obstacles of choosing excipients wisely to establish skin penetration enhancement might prevail. Therefore, development of topical/transdermal SEDDSs might be more complicated than expected.

Sulforaphane as an anticancer molecule: mechanisms of action, synergistic effects, enhancement of drug safety, and delivery systems

Sulforaphane is an isothiocyanate compound that has been derived from cruciferous vegetables. It was shown in numerous studies to be active against multiple cancer types including pancreatic, prostate, breast, lung, cervical, and colorectal cancers. Sulforaphane exerts its therapeutics action by a variety of mechanisms, such as by detoxifying carcinogens and oxidants through blockage of phase I metabolic enzymes, and by arresting cell cycle in the G2/M and G1 phase to inhibit cell proliferation. The most striking observation was the ability of sulforaphane to potentiate the activity of several classes of anticancer agents including paclitaxel, docetaxel, and gemcitabine through additive and synergistic effects. Although a good number of reviews have reported on the mechanisms by which sulforaphane exerts its anticancer activity, a comprehensive review on the synergistic effect of sulforaphane and its delivery strategies is lacking. Therefore, the aim of the current review was to provide a summary of the studies that have been reported on the activity enhancement effect of sulforaphane in combination with other anticancer therapies. Also provided is a summary of the strategies that have been developed for the delivery of sulforaphane.

Development and validation of a HPLC-UV method for the simultaneous detection and quantification of paclitaxel and sulforaphane in lipid based self-microemulsifying formulation

Paclitaxel (PTX) and sulforaphane (SFN) are known anticancer molecules. Their activity was found to be potentiated when tested concurrently. Only recently, however, a novel SFN enabled PTX self-microemulsifying formulation (SMEDDS) was developed for their simultaneous delivery. This necessitated the development of an analytical method for the simultaneous detection and quantitation of PTX and SFN. In this study, a simple and sensitive isocratic high performance liquid chromatography-ultraviolet (HPLC-UV) analytical method was developed and validated per International Conference on Harmonization guidelines to satisfy this objective. Its application was demonstrated when quantifying the amount of PTX and SFN released from the SMEDDS in various dissolution media. The separation of the analytes was performed with the aid of a reversed phase C18 column at ambient temperature using a 60:40 mixture of acetonitrile and KH2PO4 buffer (pH 5.0) as the mobile phase. PTX and SFN peaks were detected at 202 nm with high resolution without interference from excipients. This method showed linearity within 2.5-100 μg/mL range with r2 > 0.999. The limit of detection and lower limit of quantitation were 0.1638 and 0.4964 μg/mL for PTX and 0.4419 and 1.3389 μg/mL for SFN, respectively. A total of 98-101% of the injected samples was recovered with RSD of 0.06-0.68% indicating the suitability of the method for the simultaneous detection and quantitation of the molecules in dissolution media.

Dialysis encephalopathy: precipitating factors and improvement in prognosis

Cancer stem cells (CSCs) contribute to the initiation, recurrence, and metastasis of cancer; however, there are still no drugs targeting CSCs in clinical application. There are several signaling pathways playing critical roles in CSC progression, such as the Wnt, Hedgehog, Notch, Hippo, and autophagy signaling pathways. Additionally, targeting the ferroptosis signaling pathway was recently shown to specifically kill CSCs. Therefore, targeting these pathways may suppress CSC progression. The structure of small-molecule drugs shows a good spatial dispersion, and its chemical properties determine its good druggability and pharmacokinetic properties. These characteristics make small-molecule drugs show a great advantage in drug development, which is increasingly popular in the market. Thus, in this review, we will summarize the current researches on the small-molecule compounds suppressing CSC progression, including inhibitors of Wnt, Notch, Hedgehog, and autophagy pathways, and activators of Hippo and ferroptosis pathways. These small-molecule compounds emphasize CSC importance in tumor progression and propose a new strategy to treat cancer in clinic via targeting CSCs.