Development and evaluation of alginate-chitosan gastric floating beads loading with oxymatrine solid dispersion

The potential therapeutic value of the natural plant compounds matrine and oxymatrine in cardiovascular diseases

Matrine (MT) and Oxymatrine (OMT) are two natural alkaloids derived from plants. These bioactive compounds are notable for their diverse pharmacological effects and have been extensively studied and recognized in the treatment of cardiovascular diseases in recent years. The cardioprotective effects of MT and OMT involve multiple aspects, primarily including antioxidative stress, anti-inflammatory actions, anti-atherosclerosis, restoration of vascular function, and inhibition of cardiac remodeling and failure. Clinical pharmacology research has identified numerous novel molecular mechanisms of OMT and MT, such as JAK/STAT, Nrf2/HO-1, PI3 K/AKT, TGF-β1/Smad, and Notch pathways, providing new evidence supporting their promising therapeutic potential against cardiovascular diseases. Thus, this review aims to investigate the potential applications of MT and OMT in treating cardiovascular diseases, encompassing their mechanisms, efficacy, and safety, confirming their promise as lead compounds in anti-cardiovascular disease drug development.

Screening of Electrospray-operating Parameters in the Production of Alginate-Royal Jelly Microbeads Using Factorial Design

Introduction:

Royal jelly (RJ) has been consumed as food or as a supplement because of its high nutritional and medicinal values. A fresh harvested RJ is yellowish to whitish in color and contains proteins, free amino acids, lipids, vitamins, and sugar. Without proper storage conditions, such as at 4°C, the color of RJ changes to much darker yellow and produces a rancid smell. To prolong its shelf life, RJ is usually mixed with honey. Alginate, a natural and edible polymer derived from seaweed, is commonly used to encapsulate drugs and food due to its ability to form gels by reacting with divalent cations. However, there is a lack of research on the microencapsulation of RJ in alginate using electrospray. The electrospray technique has the advantage in producing consistent size and shape of alginate microbeads under optimum parameters.

Aim:

This research aimed to optimize electrospray-operating parameters in producing alginate–RJ microbeads.

Materials and Methods:

Optimization of alginate–RJ microbeads electrospray parameters was carried out using 2⁴ factorial design with three center points (19 runs). The studied parameters were flow rate, high voltage, nozzle size, and tip-to-collector distance, whereas the responses were particle size, particle size distribution, and sphericity factor. The responses of each run were analyzed using Design-Expert software.

Results:

Nozzle size is a significant parameter that influences the particle size. Flow rate is a significant parameter influencing the sphericity factor.

Conclusion:

Screening of the electrospray-operating parameters paves the way in determining the significant parameters and their design space to produce consistent alginate–RJ microbeads.

A comparative study of the effects of concentrated growth factors in two different forms on osteogenesis in vitro

Extending the release cycle of growth factors to match the cycle of bone remodeling is difficult. When using concentrated growth factors (CGFs), the release of growth factors is excessively rapid. In the present study, CGF samples were prepared by centrifugation. CGF samples were then lyophilized and grinded into a powder, which was termed freeze‑dried CGF. The freeze‑dried CGF samples were mixed with chitosan‑alginate composite hydrogels, and the mixture was lyophilized. The result was a chitosan‑alginate composite CGF membrane, which was called sustained‑release CGF. This study investigated whether freeze‑dried CGF in a chitosan‑alginate composite gel can release CGF steadily to achieve effective osteogenesis. The proliferation and osteogenic expression of MC3T3‑E1 cells induced by the supernatants from incubation with freeze‑dried CGF and sustained‑release CGF were evaluated. The concentrations of the growth factors, transforming growth factor β1 (TGF‑β1), insulin‑like growth factor‑1 (IGF‑1), platelet‑derived growth factor‑AB (PDGF‑AB) and vascular endothelial growth factor (VEGF), in these two experimental groups at different times were determined by ELISA kits. The freeze‑dried CGF showed better osteogenic performance than the sustained‑release CGF in the early stages. At later stages, the sustained‑release CGF had significant advantages over freeze‑dried CGF in terms of promoting osteogenic mineralization. By characterizing the biologic properties of the CGF in the two different forms in vitro, we obtained a better understanding of their clinical effects.

A novel controlled drug delivery system based on alginate hydrogel/chitosan micelle composites

In this study, we present a novel cross-linked unimolecular micelle based on chitosan. For controlling drug delivery via oral administration, emodin (EMO) encapsulated micelles were loaded into sodium alginate hydrogel matrix to construct the pH-sensitive hydrogel/micelle composites. The optimized formulation of micelle that consists of 8.06% CaCl₂, 1.71% chitosan and 26.52% β-GP was obtained by the combination of Box-Behnken experimental design and response surface methodology. The morphological analysis showed that the micelles exhibited a smaller diameter of about 80nm in aqueous solution, but dilated to 100-200nm in hydrogel owing to the formation of polyelectrolyte complexes. The physical characteristics in simulated digestive fluids were investigated, demonstrating that the ratio of hydrogel to micelle distinctly affected swelling, degradation and in vitro drug release behaviors. The hydrogel/micelle (1:1) exhibited a sustained-release profile, while hydrogel/micelle (3:1) exhibited a colon-specific profile. Their corresponding release mechanisms revealed that the release of drug from these two formulations followed a complex process, in which several mechanisms were involved or occurred simultaneously. These results demonstrated that the pH-sensitive hydrogel/micelle composites constructed with biocompatible materials can be a promising sustained-release or site-specific drug delivery system for instable or hydrophobic drugs.