Soluplus micelles for improving the oral bioavailability of scopoletin and their hypouricemic effect in vivo

New micelle myricetin formulation for ocular delivery: improved stability, solubility, and ocular anti-inflammatory treatment

Myricetin (Myr) is a naturally occurring flavonoid exhibiting diverse biological and pharmacological properties, but its characteristics such as water insolubility, poor aqueous stability, and poor bioavailability limit its clinical application, including in ophthalmology. To increase its clinical application in ophthalmology, Myr was designed to be encapsulated in a polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (PVCL-PVA-PEG) polymeric micelles to increases its aqueous solubility, stability, and corneal permeability to promote its efficacy in eye disease treatments. Thus, the Myr micelle ophthalmic solution was prepared and characterized encapsulation efficiency (EE), micelle size, and zeta potential. The chemical stability of Myr and the short-term storage stability of the Myr micelle ophthalmic solution were evaluated, followed by in vitro cytotoxicity and in vivo ocular irritation; in vitro cellular uptake and in vivo corneal permeation; and in vitro antioxidant activity and in vivo anti-inflammatory efficacy were also further evaluated. Myr could be incorporated into micelles with high EE. PVCL-PVA-PEG micelles significantly enhanced Myr's aqueous solubility and chemical stability. The Myr micelle ophthalmic solution also showed high storage stability. In rabbits, the Myr micelle ophthalmic solution displayed good in vitro cellular tolerance. Remarkable improvements in in vitro cellular uptake and in vivo corneal permeation were also observed in the Myr micelle ophthalmic solution, and significant improvements in the in vitro antioxidant activity and in vivo anti-inflammatory efficacy were also obtained. Overall, these results supported that the Myr micelle ophthalmic solution could be a promising nanomedicine for ocular tissues.

Scopoletin increases glucose uptake through activation of PI3K and AMPK signaling pathway and improves insulin sensitivity in 3T3-L1 cells

Coumarins have been shown to reduce blood glucose levels and improve insulin sensitivity in other studies. The purpose of this study was to investigate the effects of scopoletin, which is a type of coumarin family, on glucose uptake in 3T3-L1 cells to test the hypothesis that scopoletin exerts an antidiabetic function on adipocytes. Scopoletin significantly increased glucose uptake, which was associated with increased expression of the plasma membrane glucose transporter type 4 (PM-GLUT4) in 3T3-L1 adipocytes. This increase in PM-GLUT4 expression was promoted by phosphorylation of protein kinase B, activation of phosphatidylinositol-3-kinase (PI3K), and enhanced intracellular glucose uptake. Scopoletin also promoted phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and enhanced PM-GLUT4 expression. Scopoletin-induced glucose uptake in 3T3-L1 adipocytes was inhibited by treatment with the PI3K inhibitor wortmannin and the AMPK inhibitor compound C. These results suggest that scopoletin has an antidiabetic effect by stimulating GLUT4 translocation to the PM through activation of the PI3K and AMPK pathways in 3T3-L1 adipocytes, thereby upregulating glucose uptake.

Comparison of Chitosan Nanoparticles and Soluplus Micelles to Optimize the Bioactivity of Posidonia oceanica Extract on Human Neuroblastoma Cell Migration

Posidonia oceanica (L.) Delile is a marine plant endemic of Mediterranean Sea endowed with interesting bioactivities. The hydroalcholic extract of P. oceanica leaves (POE), rich in polyphenols and carbohydrates, has been shown to inhibit human cancer cell migration. Neuroblastoma is a common childhood extracranial solid tumor with high rate of invasiveness. Novel therapeutics loaded into nanocarriers may be used to target the migratory and metastatic ability of neuroblastoma. Our goal was to improve both the aqueous solubility of POE and its inhibitory effect on cancer cell migration. Methods: Chitosan nanoparticles (NP) and Soluplus polymeric micelles (PM) loaded with POE have been developed. Nanoformulations were chemically and physically defined and characterized. In vitro release studies were also performed. Finally, the inhibitory effect of both nanoformulations was tested on SH-SY5Y cell migration by wound healing assay and compared to that of unformulated POE. Results: Both nanoformulations showed excellent physical and chemical stability during storage, and enhanced the solubility of POE. PM-POE improved the inhibitory effect of POE on cell migration probably due to the high encapsulation efficiency and the prolonged release of the extract. Conclusions: For the first time, a phytocomplex of marine origin, i.e., P. oceanica extract, has enhanced in terms of acqueous solubility and bioactivity once encapsulated inside nanomicelles.

Promotion of a quality standard for Porana sinensis Hemsl. based on the efficacy-oriented Effect-Constituent Index

Multicompound determination for the quality control of traditional Chinese medicine (TCM) may often be inadequate, since these compounds may not be associated with, or fully represent, the clinical effects of TCM. Moreover, the individual contributions of each constituent to the pharmacological effect are often not considered. In China, Porana sinensis is widely used as a substitute for Erycibe sources to treat joint pain and rheumatoid arthritis. The existing quality control methods for P. sinensis neither consider the individual contributions of various compounds nor control the actual quality associated with different clinical efficacies. In the present study, a novel efficacy-oriented approach, named the effect-constituent index (ECI), was established for P. sinensis. Analyses of the spectrum-effect relationship and components in rat plasma were conducted to systematically and scientifically select quality markers. Quantitative analysis of multicomponents via a single marker method was introduced to enhance the practical application value of the established ECI. The established ECI shows a good ability to distinguish and predict the bioeffect-based quality of P. sinensis. The present study also provides a reference for the establishment and application of ECI as a quality control method for TCMs.

Polymeric Nanomicelles of Soluplus® as a Strategy for Enhancing the Solubility, Bioavailability and Efficacy of Poorly Soluble Active Compounds

:

Soluplus® is a commercially available graft amphipathic copolymer consisting of polyvinyl caprolactam, polyvinyl acetate, and polyethyleneglycol (13% PEG 6000/57% vinyl caprolactam/30% vinyl acetate). Among the various applications of this solubilizer excipient, produced by BASF, such as the production of amorphous solid dispersions of insoluble drugs, Soluplus® has shown to be able to form nano-sized micelles in water or other aqueous solutions, characterized by a very small diameter and an exceptionally narrow size distribution. These formulations allow to improve the solubility and physical stability in aqueous media of poorly soluble drugs. This review summarizes the recent data from literature on the methods of production and characterization of drugloaded nanomicelles based on Soluplus®, highlighting the potential fields of therapeutic application.

Scopoletin Suppresses Activation of Dendritic Cells and Pathogenesis of Experimental Autoimmune Encephalomyelitis by Inhibiting NF-κB Signaling

Scopoletin, a phenolic coumarin derived from many medical or edible plants, is involved in various pharmacological functions. In the present study, we showed that Scopoletin effectively ameliorated experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), through novel regulatory mechanisms involving inhibition of NF-κB activity in dendritic cells (DCs). Scopoletin treatment significantly improved the severity of the disease and prominently decreased inflammation and demyelination of central nervous system (CNS) in EAE mice. Disease alleviation correlated with the downregulation of major histocompatibility complex (MHC) class II, CD80 and CD86, expressed on DCs of CNS or spleens, and the infiltration and polarization of encephalitogenic Th1/Th17 cells. Consistent with the in vivo data, Scopoletin-treated, bone marrow-derived dendritic cells (BM-DCs) exhibited reduced expression of MHC class II and costimulatory molecules (e.g., CD80 and CD86) and reduced NF-κB phosphorylation. These findings, for the first time, demonstrated the ability of Scopoletin to impair DC activation, downregulating pathogenic Th1/Th17 inflammatory cell responses and, eventually, reducing EAE severity. Our study demonstrates new evidence that natural products derived from medical or edible plants, such as Scopoletin, will be valuable in developing a novel therapeutic agent for MS in the future.

Risk assessment and QbD based optimization of an Eprosartan mesylate nanosuspension: In-vitro characterization, PAMPA and in-vivo assessment

Quality by design (QbD) principles were implemented to understand the product and process variables of sonoprecipitation technique, for preparation of eprosartan mesylate (EM) nanosuspension. Quality risk management approach was utilized to identify and assess high-risk attributes affecting critical quality attributes (CQA's), prioritizing the number of experiments. The effect of critical material attributes (CMA's) and critical process parameters (CPP's) (soluplus concentration, drug concentration ultrasonication amplitude) on z-average particle size and PDI were investigated using a central composite face-centered design (CCF). Further, design space with criteria set of CMA's and CPP's was established to offer assurance of quality. The optimal formulation, identified using numerical optimization method, was further lyophilized and evaluated for redispersibility, solubility saturation, dissolution kinetic and in-vitro dissolution behavior. The EM nanoparticles were in an amorphous state as confirmed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. The stability study conducted for a span of 6 months attests physical and chemical stability of EM dry nanosuspension in an amorphous state when stored at 4 °C. The enhanced solubility and in-vitro dissolution of EM nanosuspension may be attributed to the reduced particle size and alteration of the physical state from a crystalline to an amorphous state. Further, the optimized formulation was subjected to in-vitro and ex-vivo transport study using parallel artificial membrane permeability assay (PAMPA) and rat everted gut sac model respectively. The transport studies revealed successful permeation enhancement of EM nanoparticle when compared with EM API and physical mixture (PM). The absolute bioavailability of EM API was 7.1% and improved to 39.9% for EM nanosuspension, suggesting that nanoformulation had overcome solubility and permeability limited bioavailability which was observed with EM API.

Drop-On-Powder 3D Printing of Tablets with an Anti-Cancer Drug, 5-Fluorouracil

This study reports the first case of an innovative drop-on-powder (DoP) three-dimensional (3D) printing technology to produce oral tablets (diameters of 10 mm and 13 mm) loaded with an anticancer model drug, 5-fluorouracil (FLU). For this study, a composition of the powder carrier containing CaSO₄ hydrates, vinyl polymer, and carbohydrate was used as the matrix former, whereas 2-pyrrolidone with a viscosity like water was used as a binding liquid or inkjet ink. All tablets were printed using a commercial ZCorp 3D printer with modification. The resultant tablets were subject to coating with various polymeric solutions containing the drug. The composition of the polymeric solutions was adjusted at drug: polymer(s) 1:1 (w/w) ratio. Either Soluplus^® (SOL) alone or in combination with polyethylene glycol (PEG) was used to develop the coating solution of 2.5% (w/v) concentration. The particle size analysis, flow test, and particle morphology studies revealed mono-modal narrow size distribution, good flow properties, and porous loosely bound texture (of the tablets), respectively. Moreover, the advanced application of the fluorescence microscopy showed a homogenous distribution of the drug throughout the surface of the 3D printed tablets. The in vitro dissolution studies showed that the tablet compositions, dimensions, and the coating solution compositions influenced the release of the drug from the tablets. It can be concluded that our innovative DoP 3D printing technology can be used to fabricate personalized dosage forms containing optimized drug content with high accuracy and shape fidelity. This is particularly suitable for those drugs that are highly unstable in thermal processing and cannot withstand the heat treatment, such as in fused deposition modeling (FDM) 3D printing.

Anti-gout Potential of Malaysian Medicinal Plants

Gout is a type of arthritis that causes painful inflammation in one or more joints. In gout, elevation of uric acid in the blood triggers the formation of crystals, causing joint pain. Malaysia is a mega-biodiversity country that is rich in medicinal plants species. Therefore, its flora might offer promising therapies for gout. This article aims to systematically review the anti-gout potential of Malaysian medicinal plants. Articles on gout published from 2000 to 2017 were identified using PubMed, Scopus, ScienceDirect, and Google Scholar with the following keyword search terms: “gout,” “medicinal plants,” “Malaysia,” “epidemiology,” “in vitro,” and “in vivo.” In this study, 85 plants were identified as possessing anti-gout activity. These plants had higher percentages of xanthine oxidase inhibitory activity (>85%); specifically, the Momordica charantia, Chrysanthemum indicum, Cinnamomum cassia, Kaempferia galanga, Artemisia vulgaris, and Morinda elliptica had the highest values, due to their diverse natural bioactive compounds, which include flavonoids, phenolics, tannin, coumarins, luteolin, and apigenin. This review summarizes the anti-gout potential of Malaysian medicinal plants but the mechanisms, active compounds, pharmacokinetics, bioavailability, and safety of the plants still remain to be elucidated.

Amorphous Solid Dispersion of Epigallocatechin Gallate for Enhanced Physical Stability and Controlled Release

Epigallocatechin gallate (EGCG) has been recognized as the most prominent green tea extract due to its healthy influences. The high instability and low bioavailability, however, strongly limit its utilization in food and drug industries. This work, for the first time, develops amorphous solid dispersion of EGCG to enhance its bioavailability and physical stability. Four commonly used polymeric excipients are found to be compatible with EGCG in water-dioxane mixtures via a stepwise mixing method aided by vigorous mechanical interference. The dispersions are successfully generated by lyophilization. The physical stability of the dispersions is significantly improved compared to pure amorphous EGCG in stress condition (elevated temperature and relative humidity) and simulated gastrointestinal tract environment. From the drug release tests, one of the dispersions, EGCG-Soluplus^® 50:50 (w/w) shows a dissolution profile that only 50% EGCG is released in the first 20 min, and the remains are slowly released in 24 h. This sustained release profile may open up new possibilities to increase EGCG bioavailability via extending its elimination time in plasma.

Synthesis and structure-activity relationships of sinenxan A derivatives as multidrug resistance reversal agents

Two types of sinenxan A derivatives with different side chains at C-5 were synthesized and evaluated for their in vitro multidrug resistant reversal activities. Several derivatives exhibited better activities than the positive control verapamil. The structure-activity relationships of these derivatives suggested that a carbonyl group at C-13 and the length of side chain at C-5 are important for the activity.