The potential role of GSK-3ß signaling pathway for amelioration actions of ketamine on the PTSD rodent model.

RATIONALE: Post-traumatic stress disorder (PTSD) is a complex, chronic psychiatric disorder typically triggered by life-threatening events and, as yet, lacks a specialized pharmacological treatment. The potential therapeutic role of ketamine, an N-methyl-D-aspartate receptor antagonist, in mitigating PTSD has been the subject of investigation. OBJECTIVE: The aim of this study was to elucidate alterations in the glycogen synthase kinase-3ß (GSK-3ß) signaling pathway in response to ketamine intervention, using the single prolonged stress (SPS) model of PTSD at a molecular level. METHODS: PTSD-like symptoms were simulated using the SPS model. Ketamine (10 mg/kg) and GSK-3ß antagonist SB216763 (5 mg/kg) were then administered intraperitoneally. Stress-related behavior was evaluated through the open field test (OFT) and the elevated plus maze test (EMPT). Additionally, brain activity was analyzed using quantitative electroencephalography (qEEG). Changes in protein and mRNA expressions of glucocorticoid receptor (GR), brain-derived neurotrophic factor (BDNF), GSK-3ß, phosphorylated ser-9 GSK-3ß (p-GSK-3ß), FK506 binding protein 5 (FKBP5), and corticotropin-releasing hormone (CRH) were assessed in the hypothalamus via western blot and qPCR. RESULTS: SPS-exposed rats exhibited reduced distance and time spent in the center of the open arms, a pattern divergent from control rats. qEEG readings revealed SPS-induced increases in alpha power, low gamma and high gamma power. Furthermore, SPS triggered an upregulation in the protein and gene expression of GSK-3ß, GR, BDNF, p-GSK-3ß, and FKBP5, and downregulated CRH expression in the hypothalamus. Ketamine administration following the SPS procedure counteracted these changes by increasing the time spent in the center of the OFT, the distance traversed in the open arms of the EMPT, and mitigating SPS-induced alterations in cerebral cortex oscillations. Moreover, ketamine reduced the protein levels of GSK-3ß, GR, p-GSK-3ß, and altered the ratio of p-GSK-3ß to GSK-3ß. Gene expression of GSK-3ß, GR, BDNF, and FKBP5 decreased in the SPS-Ket group compared to the SPS-Sal group. CONCLUSIONS: Ketamine appeared to remediate the abnormal GSK-3ß signaling pathway induced by SPS. These findings collectively suggest that ketamine could be a promising therapeutic agent for PTSD symptoms, working through the modulation of the GSK-3ß signaling pathway.

Layer-by-Layer Assembly of Lipid Nanobubbles on Microneedles for Ultrasound-Assisted Transdermal Drug Delivery.

Microneedles as a typical device for transdermal drug delivery provide an alternative route for drug administration with minimal digestion by organs and better patient compliance. However, diffusion of passively released drug molecules within the skin tissue mainly depends on the interstitial fluid, which may be affected by different physiological conditions of individuals. Herein, we propose a nanobubble-modified microneedle patch for ultrasound-assisted drug delivery, which provides additional driving force for penetration and diffusion of the drug molecules. Layer-by-layer self-assembled drug-containing nanobubbles on the surfaces of microneedles trigger active drug release upon application of ultrasound. The concomitant microstreaming caused by cavitation effects facilitates the penetration and diffusion of drug molecules in the gelatin gel model and the ex vivo porcine skin model. The proposed drug delivery strategy holds great promise for rapid transdermal drug delivery with enhanced penetration and diffusion of the released drugs.