Binding effects of Alpinia galanga oil and its nanoemulsion 1 to GABAA receptors in rat cortical membranes

Anesthetic activity of Alpinia galanga oil (AGO) has been reported however the mechanism of action in mammals has not been clear. In the present study, the binding effects of AGO and its three active components to gamma-aminobutyric acid type A (GABAA) receptor in cortical membranes of Sprague-Dawley rats were firstly investigated using a [3H]muscimol binding assay. Dimethyl sulfoxide (DMSO) was used to deliver these test samples. The results showed that only AGO and methyl eugenol displayed positive modulation at the highest concentration whereas 1,8-cineole and 4-allylphenyl acetate were inactive. An oil-in-water nanoemulsion containing 20%w/w AGO (NE-AGO) was formulated to deliver AGO instead of DMSO. This NE-AGO significantly enhanced a specific [3H]muscimol binding to 179% of the control with EC50 of 391 µg/mL. The result correlates well to the amount of methyl eugenol in AGO. This result confirms that the anesthetic activity of AGO and methyl eugenol is associated with GABAA receptor modulation, while that of 1,8-cineole and 4-allylphenyl acetate is not and may instead be related to other mechanisms. AGO showed well-tolerated by human cells. Therefore, the formulated NE-AGO might be a promising alternative anesthetic product for humans.

Covalent Decoration of Cortical Membranes with Graphene Oxide as a Substrate for Dental Pulp Stem Cells

(1) Background: The aim of this study was to optimize, through a cheap and facile protocol, the covalent functionalization of graphene oxide (GO)-decorated cortical membrane (Lamina®) in order to promote the adhesion, the growth and the osteogenic differentiation of DPSCs (Dental Pulp Stem Cells); (2) Methods: GO-coated Laminas were fully characterized by Scannsion Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) analyses. In vitro analyses of viability, membrane integrity and calcium phosphate deposition were performed; (3) Results: The GO-decorated Laminas demonstrated an increase in the roughness of Laminas, a reduction in toxicity and did not affect membrane integrity of DPSCs; and (4) Conclusions: The GO covalent functionalization of Laminas was effective and relatively easy to obtain. The homogeneous GO coating obtained favored the proliferation rate of DPSCs and the deposition of calcium phosphate.