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Golding, P.

Publications and source records attributed to Golding, P..

3 recordsLinked to original sources

Preclinical Comparison of DMT and 5-MeO-DMT Reveals Behavioral Dissociation, Distinct TrkB Activation and Differential Plasticity Profiles

N, N-dimethyltryptamine (DMT) and 5-methoxy-N, N-dimethyltryptamine (5-MeO-DMT) are structurally related tryptamine psychedelics with emerging therapeutic potential, yet their comparative acute pharmacology and longer-term neuroplastic effects remain incompletely defined. Here we show that DMT produces a bell-shaped dose-response curve in the mouse head-twitch response (HTR) assay, whereas 5-MeO-DMT elicits a monotonic increase. Selective antagonism at 5-HT2A or 5-HT1D receptors, or agonism at 5-HT1A, robustly attenuates HTR for both compounds without abolishing their ability to reduce marble burying, a screening assay for OCD-like behavior. Acutely, both agents elevate TrkB phosphorylation in a region-specific manner, with broader engagement by DMT across default-mode-network and hippocampal territories. Twelve days after a single dose, both compounds increase synaptic proteins (PSD-95, synaptophysin; SV2A for DMT), while DMT uniquely lowers hippocampal BDNF and reprograms frontal-cortex glutathione and energy metabolism. These findings demonstrate that acute hallucinogenic-like activity and selected therapeutic-like behavioral and plasticity outcomes can be pharmacologically dissociated, informing the rational design of more tolerable, scalable psychedelic-based treatments.

neuroscience↗

MDMA-Enhanced Exposure Therapy Reverses PTSD-Like Features In a Learned Helplessness Mouse Model

Post-traumatic stress disorder (PTSD) is a highly prevalent, debilitating psychiatric condition. Existing treatments are ineffective for many patients. 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy has demonstrated substantial clinical efficacy but relies on prolonged, resource-intensive therapeutic protocols that limit scalability and accessibility. Here, we investigated whether combining MDMA with exposure-based intervention could enhance therapeutic efficiency in a preclinical model of PTSD-like behavior. Using a learned helplessness paradigm in mice, we identified trauma-susceptible individuals based on persistent escape failures following inescapable stress. Traumatised mice subsequently received brief treatment regimens consisting of MDMA or saline vehicle administered with or without exposure to the traumatic cue. Behavioral outcomes were tracked longitudinally using active avoidance performance as the primary endpoint, complemented by assays of anxiety-like, depressive-like, cognitive, and social behaviors. MDMA treatment markedly reduced trauma-associated behavioral deficits. MDMA combined with exposure produced rapid and sustained recovery compared to control conditions. Statistical analyses revealed significant treatment- and time-dependent effects on avoidance behavior, indicating accelerated resilience acquisition in MDMA-treated groups. Additional behavioral assays demonstrated dose-dependent effects of MDMA on anxiety- and depression-related measures. Together, these findings provide proof-of-principle that pharmacological modulation with MDMA can enhance exposure-driven behavioral recovery, supporting a strategy to integrate MDMA into more efficient and accessible PTSD treatment frameworks. This work establishes a preclinical foundation for clinical studies aimed at optimizing MDMA-assisted interventions to improve scalability and patient access.

neuroscience↗

Intramuscular mRNA BNT162b2 vaccine against SARS-CoV-2 induces robust neutralizing salivary IgA

Intramuscularly administered vaccines stimulate robust serum neutralizing antibodies, yet they are often less competent in eliciting sustainable sterilizing immunity at the mucosal level. Our study uncovers, strong neutralizing mucosal component (NT50 [≤] 50pM), emanating from intramuscular administration of an mRNA vaccine. We show that saliva of BNT162b2 vaccinees contains temporary IgA targeting the Receptor-Binding-Domain (RBD) of SARS-CoV-2 spike protein and demonstrate that these IgAs are key mediators of potent neutralization. RBD-targeting IgAs were found to associate with the Secretory Component, indicating their bona-fide transcytotic origin and their dimeric tetravalent nature. The mechanistic understanding of the exceptionally high neutralizing activity provided by mucosal IgA, acting at the first line of defence, will advance vaccination design and surveillance principles, pointing to novel treatment approaches, and to new routes of vaccine administration and boosting. Significance statementWe unveiled powerful mucosal neutralization upon BNT162b2 vaccination, mediated by temporary polymeric IgA and explored its longitudinal properties. We present a model, whereby the molecular architecture of polymeric mucosal IgA and its spatial properties are responsible for the outstanding SARS-CoV-2 neutralization potential. We established a methodology for quantitative comparison of immunoreactivity and neutralization for IgG and IgAs in serum and saliva in molar equivalents for standardization in diagnostics, surveillance of protection and for vaccine evaluations.

microbiology↗