Fabrication of timed-release indomethacin core-shell tablets for chronotherapeutic drug delivery using dual nozzle Fused Deposition Modeling (FDM) 3D printing

Development of multiple structured extended release tablets via hot melt extrusion and dual-nozzle fused deposition modeling 3D printing

The study aims to fabricate extended release (ER) tablets using a dual-nozzle fused deposition modeling (FDM) three-dimensional (3D) printing technology based on hot melt extrusion (HME), using caffeine as the model compound. Three different ER tablets were developed, which obtained "delayed-release", "rapid-sustained release", and "release-lag-release" properties. Each type of tablet was printed with two different formulations. A novel printing method was employed in this study, which is to push the HME filament from behind with polylactic acid (PLA) to prevent sample damage by gears during the printing process. Powder X-ray diffractometry (PXRD) and differential scanning calorimetry (DSC) results showed that caffeine was predominately amorphous in the final tablets. The dissolution of 3D printed tablets was assessed using a USP-II dissolution apparatus. ER tablets containing PVA dissolved faster than those developed with Kollicoat IR. Overall, this study revealed that ER tablets were successfully manufactured through HME paired with dual-nozzle FDM 3D printing and demonstrated the power of 3D printing in developing multi-layer tablets with complex structures.

3D Printing Direct Powder Extrusion in the Production of Drug Delivery Systems: State of the Art and Future Perspectives

The production of tailored, on-demand drug delivery systems has gained attention in pharmaceutical development over the last few years, thanks to the application of 3D printing technology in the pharmaceutical field. Recently, direct powder extrusion (DPE) has emerged among the extrusion-based additive manufacturing techniques. It is a one-step procedure that allows the direct processing of powdered formulations. The aim of this systematic literature review is to analyze the production of drug delivery systems using DPE. A total of 27 articles have been identified through scientific databases (Scopus, PubMed, and ScienceDirect). The main characteristics of the three types of 3D printers based on DPE have been discussed. The selection of polymers and auxiliary excipients, as well as the flowability of the powder mixture, the rheological properties of the molten material, and the printing temperatures have been identified as the main critical parameters for successful printing. A wide range of drug delivery systems with varied geometries and different drug release profiles intended for oral, buccal, parenteral, and transdermal routes have been produced. The ability of this technique to manufacture personalized, on-demand drug delivery systems has been proven. For all these reasons, its implementation in hospital settings in the near future seems promising.

Leonurine alleviates rheumatoid arthritis by regulating the Hippo signaling pathway

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease that can cause joint inflammation and damage. Leonurine (LE) is an alkaloid found in Leonurus heterophyllus. It has anti-inflammatory effects.

HYPOTHESIS/PURPOSE

The molecular mechanisms by which LE acts in RA are unclear and further investigation is required.

METHODS

Mice with collagen-induced arthritis (CIA), and RA-fibroblast-like synoviocytes (FLSs) isolated from them were used as in vivo and in vitro models of RA, respectively. The therapeutic effects of LE on CIA-induced joint injury were investigated by micro-computed tomography, and staining with hematoxylin and eosin and Safranin-O/Fast Green. Cell Counting Kit-8, a Transwell® chamber, enzyme-linked immunosorbent assays, RT-qPCR, and western blotting were used to investigate the effects of LE on RA-FLS viability, migratory capacity, inflammation, microRNA-21 (miR-21) levels, the Hippo signaling pathway, and the effects and intrinsic mechanisms of related proteins. Dual luciferase was used to investigate the binding of miR-21 to YOD1 deubiquitinase (YOD1) and yes-associated protein (YAP). Immunofluorescence was used to investigate the localization of YAP within the nucleus and cytoplasm.

RESULTS

Treatment with LE significantly inhibited joint swelling, bone damage, synovial inflammation, and proteoglycan loss in the CIA mice. It also reduced the proliferation, cell colonization, migration/invasion, and inflammation levels of RA-FLSs, and promoted miR-21 expression in vitro. The effects of LE on RA-FLSs were enhanced by an miR-21 mimic and reversed by an miR-21 inhibitor. The dual luciferase investigation confirmed that both YOD1 and YAP are direct targets of miR-21. Treatment with LE activated the Hippo signaling pathway, and promoted the downregulation and dephosphorylation of MST1 and LATS1 in RA, while inhibiting the activation of YOD1 and YAP. Regulation of the therapeutic effects of LE by miR-21 was counteracted by YOD1 overexpression, which caused the phosphorylation of YAP and prevented its nuclear ectopic position, thereby reducing LE effect on pro-proliferation-inhibiting apoptosis target genes.

CONCLUSION

LE regulates the Hippo signaling pathway through the miR-21/YOD1/YAP axis to reduce joint inflammation and bone destruction in CIA mice, thereby inhibiting the growth and inflammation of RA-FLSs. LE has potential for the treatment of RA.

Development of 3D-Printed Bicompartmental Devices by Dual-Nozzle Fused Deposition Modeling (FDM) for Colon-Specific Drug Delivery

Dual-nozzle fused deposition modeling (FDM) is a 3D printing technique that allows for the simultaneous printing of two polymeric filaments and the design of complex geometries. Hence, hybrid formulations and structurally different sections can be combined into the same dosage form to achieve customized drug release kinetics. The objective of this study was to develop a novel bicompartmental device by dual-nozzle FDM for colon-specific drug delivery. Hydroxypropylmethylcellulose acetate succinate (HPMCAS) and polyvinyl alcohol (PVA) were selected as matrix-forming polymers of the outer pH-dependent and the inner water-soluble compartments, respectively. 5-Aminosalicylic acid (5-ASA) was selected as the model drug. Drug-free HPMCAS and drug-loaded PVA filaments suitable for FDM were extruded, and their properties were assessed by thermal, X-ray diffraction, microscopy, and texture analysis techniques. 5-ASA (20% w/w) remained mostly crystalline in the PVA matrix. Filaments were successfully printed into bicompartmental devices combining an outer cylindrical compartment and an inner spiral-shaped compartment that communicates with the external media through an opening. Scanning electron microscopy and X-ray tomography analysis were performed to guarantee the quality of the 3D-printed devices. In vitro drug release tests demonstrated a pH-responsive biphasic release pattern: a slow and sustained release period (pH values of 1.2 and 6.8) controlled by drug diffusion followed by a faster drug release phase (pH 7.4) governed by polymer relaxation/erosion. Overall, this research demonstrates the feasibility of the dual-nozzle FDM technique to obtain an innovative 3D-printed bicompartmental device for targeting 5-ASA to the colon.