Liposome Loaded Ion/Temperature Dual Responsive Gellan Gum Hydrogel as Potential Nasal-To-Brain Delivery System

In Vitro and In Vivo Evaluation of Lactoferrin-Modified Liposomal Etomidate with Enhanced Brain-Targeting Effect for General Anesthesia

Etomidate is a general anesthetic that has shown good hemodynamic stability without significant cardiovascular or respiratory depression. Despite several kinds of dosage forms having been reported for this drug, formulation types are very limited in clinical practice, and brain-targeted formulations for this central nervous system (CNS) drug have been rarely reported. Moreover, studies on the biocompatibility, toxicity, and anesthetic effects of the etomidate preparations in vivo were inadequate. The present study was to develop lactoferrin-modified liposomal etomidate (Eto-lip-LF) for enhanced drug distribution in the brain and improved anesthetic effects. Eto-lip-LF had good stability for storage and hemocompatibility for intravenous injection. Compared with the non-lactoferrin-containing liposomes, the lactoferrin-modified liposomes had notably enhanced brain-targeting ability in vivo, which was probably realized by the binding of transferrin with the transferrin and lactoferrin receptors highly distributed in the brain. Eto-lip-LF had a therapeutic index of about 25.3, higher than that of many other general anesthetics. Moreover, compared with the commercial etomidate emulsion, Eto-lip-LF could better achieve rapid onset of general anesthesia and rapid recovery from anesthesia, probably due to the enhanced drug delivery to the brain. The above results demonstrated the potential of this lactoferrin-modified liposomal etomidate to become an alternative preparation for clinical general anesthesia.

Hydrogels for Mucosal Drug Delivery

Mucosal tissues are often a desirable site of drug action to treat disease and engage the immune system. However, systemically administered drugs suffer from limited bioavailability in mucosal tissues where technologies to enable direct, local delivery to these sites would prove useful. In this Spotlight on Applications article, we discuss hydrogels as an attractive means for local delivery of therapeutics to address a range of conditions affecting the eye, nose, oral cavity, gastrointestinal, urinary bladder, and vaginal tracts. Considering the barriers to effective mucosal delivery, we provide an overview of the key parameters in the use of hydrogels for these applications. Finally, we highlight recent work demonstrating their use for inflammatory and infectious diseases affecting these tissues.

Temperature-Ion-pH Triple Responsive Gellan Gum as In Situ Hydrogel for Long-Acting Cancer Treatment

Background: Promising cancer chemotherapy requires the development of suitable drug delivery systems (DDSs). Previous research has indicated that a hydrogel is a powerful DDS for tumor therapy and holds great potential to offer a feasible method for cancer management. Methods: In this study, glutathione-gellan gum conjugate (GSH-GG) was synthesized through chemical reaction. Doxorubicin hydrochloride (DOX) was loaded into GSH-GG to accomplish DOX-loaded GSH-GG. The properties, injectability, drug release, and in vitro and in vivo anticancer effects of DOX-loaded GSH-GG were tested. Results: DOX-loaded GSH-GG showed a temperature-ion dual responsive gelling property with good viscosity, strength, and injectability at an optimized gel concentration of 1.5%. In addition, lower drug release was found under acidic conditions, offering beneficial long-acting drug release in the tumor microenvironment. DOX-loaded GSH-GG presented selective action by exerting substantially higher cytotoxicity on cancer cells (4T1) than on normal epithelial cells (L929), signifying the potential of complete inhibition of tumor progression, without affecting the health quality of the subjects. Conclusions: GSH-GG can be applied as a responsive gelling material for delivering DOX for promising cancer therapy.

Antitumor Effect of Co-Loading Natural Active Compound of Okofuran (Usenamine) and Photosensitizer Nano-Liposomes

Objective: In this study, we developed a nano-liposome (LIP-RUA) to evaluate the in vitro anti-lung cancer activity. In this regard, nano-liposome co-loaded with photosensitizer (RB), upconverting nanoparticles (UCNPs), and natural active compound usenamine (ACU). Methods: LIP-RUA was obtained by encapsulating ACU/RB/UCNPs by thin film dispersion method. The physicochemical properties were investigated by using an instrument; the efficiency of liposomes producing reactive oxygen species (ROS) was detected by SOSG probe; the uptake of LIP-RUA by A549 lung cancer cells was observed by confocal microscopy. Results: The particle size of the prepared LIP-RUA was about 150 nm, the surface potential was about −12 mV, and the entrapment efficiency of RB and ACU reached 54.5% and 86.5%, respectively. Experimental tasks showed that LIP-RUA could significantly improve the growth inhibitory effect of the drug on lung cancer cells, and the median effective inhibitory concentration (IC50) under laser irradiation was 15.33 μmol/L. Conclusion: LIP-RUA provides a new idea for the combination of photodynamic chemotherapy for the treatment of lung cancer. The liposome platform is expected to enhance the in vivo penetration of photodynamic therapy and the combined effect of photodynamic chemotherapy.