Lind, E. B. | Search bioRxiv

bioRxiv2025

Cocaine sensitization and accumbens shell plasticity depend on biological sex and gonadal hormones in C57BL/6J mice

Biological sex as a defining variable in drug sensitivity remains poorly understood. Here, we combine behavioral and electrophysiological analyses to examine the influence of sex and gonadal hormones on cocaine-induced psychomotor sensitization and nucleus accumbens shell (NAcSh) plasticity in the prominent C57BL/6J mouse strain. Males exhibited greater cocaine-evoked locomotor activity than females; castration attenuated responses, whereas ovariectomy enhanced them. This behavioral phenotype is opposite to what occurs in rats. A 10-14 day abstinence period abolished the sex difference in intact animals, and gonadectomy reduced cocaine-induced behavioral plasticity. Recordings from 309 medium spiny neurons revealed sex-dependent NAcSh plasticity. In males, cocaine decreased neuronal excitability, while in females it induced estrous cycle-dependent plasticity characterized by reduced excitability during diestrus relative to estrus. These effects were driven by cocaine-induced modulation of voltage-gated sodium channels. Cocaine potentiated glutamatergic strength in males but elicited estrous cycle-dependent depotentiation in females. These adaptations in excitability and glutamatergic strength were abolished by gonadectomy, and paralleled diminished behavioral plasticity during abstinence. These data illustrate that biological sex and hormonal milieu critically shape cocaine-induced plasticity, offering a more nuanced framework than the traditional notion of heightened female sensitivity to drugs of abuse.

neuroscience↗

bioRxiv2025

Oral prodrug of a novel glutathione surrogate reverses metabolic dysregulation and attenuates neurodegenerative process in APP/PS1 mice

Glycation-induced oxidative stress underlies the numerous metabolic ravages of Alzheimers disease (AD). Reduced glutathione levels in AD lead to increased oxidative stress, including glycation-induced pathology. Previously, we showed that the accumulation of reactive 1,2-dicarbonyls such as methylglyoxal, the major precursor of non-enzymatic glycation products, was reduced by the increased function of GSH-dependent glyoxalase-1 enzyme in the brain. In this two-pronged study, we evaluate the therapeutic efficacy of an orally bioavailable prodrug of our lead glyoxalase substrate, pro-{psi}-GSH, for the first time in a transgenic Alzheimers disease mouse model. This prodrug delivers pharmacodynamically relevant brain concentrations of {psi}-GSH upon oral delivery. Chronic oral dosing of pro-{psi}-GSH effectively reverses the cognitive decline observed in the APP/PS1 mouse model. The prodrug successfully mirrors the robust effects of the parent drug i.e., reducing amyloid pathology, glycation stress, neuroinflammation, and the resultant neurodegeneration in these mice. We also report the first metabolomics study of such a treatment, which yields key biomarkers linked to the reversal of AD-related metabolic dysregulation. Collectively, this study establishes pro-{psi}-GSH as a viable, disease-modifying therapy for AD and paves the way for further preclinical advancement of such therapeutics. Metabolomic signatures identified could prove beneficial in the development of treatment-specific clinically translatable biomarkers. ABSTRACT GRAPHIC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=196 SRC="FIGDIR/small/633247v1_ufig1.gif" ALT="Figure 1"> View larger version (60K): org.highwire.dtl.DTLVardef@a9c2c0org.highwire.dtl.DTLVardef@130ed71org.highwire.dtl.DTLVardef@134a19corg.highwire.dtl.DTLVardef@5e0f89_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗