Author Archives: samweiss
Multisystem stress response biotypes: a precision psychiatry approach to identifying and treating multidimensional risk factors for anhedonia in adolescence
Adolescence is a critical period of developmental changes in neurobiological and psychological systems, rendring it both a period of vulnerability for the emergence of risk factors associated with psychopathology and a period of opportunity for the implementation of targeted prevention and interventions. Anhedonia (i.e., the reduced ability to anticipate or experience pleasure) is a core … Read more
Neurosteroid [3α,5α]3-hydroxypregnan-20-one inhibition of chemokine monocyte chemoattractant protein-1 in alcohol-preferring rat brain neurons, microglia, and astroglia
Background: Neuroimmune dysfunction in alcohol use disorder (AUD) is associated with activation of myeloid differentiation primary response 88 (MyD88)-dependent Toll-like receptors (TLR) resulting in overexpression of the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). MCP-1 overexpression in the brain is linked to anxiety, higher alcohol intake, neuronal death, and activation of microglia observed in AUD. The neurosteroid … Read more
Interneuron-selective HCN channel knockdown in prelimbic cortex of female rats mimics effects of chronic ethanol exposure
Our laboratory has previously shown that chronic ethanol exposure elicits enhanced working memory performance in female, but not male, adult Sprague-Dawley rats, indicative of a fundamental sex difference in cortical plasticity. Recent studies have furthermore revealed that females display markedly reduced HCN-mediated channel activity in inhibitory Martinotti interneurons after chronic ethanol exposure that is similarly … Read more
Neurosteroid [3α,5α]-3-Hydroxy-pregnan-20-one Enhances the CX3CL1-CX3CR1 Pathway in the Brain of Alcohol-Preferring Rats with Sex-Specificity
This study investigates the impact of allopregnanolone ([3α,5α]3-hydroxypregnan-20-one or 3α,5α-tetrahydroprogesterone (3α,5α-THP); 10 mg/kg, IP) on fractalkine/CX3-C motif chemokine ligand 1 (CX3CL1) levels, associated signaling components, and markers for microglial and astrocytic cells in the nucleus accumbens (NAc) of male and female alcohol-preferring (P) rats. Previous research suggested that 3α,5α-THP enhances anti-inflammatory interleukin-10 (IL-10) cytokine production … Read more
Psychiatry Researchers Investigate Why Some Adolescents Lose Motivation and Pleasure
CHAPEL HILL, NC – Anhedonia, the inability to anticipate or experience pleasure, can emerge during adolescence and often precedes the onset of more severe psychopathology such as mood disorders and psychosis. The condition is difficult to treat, but UNC Psychiatry researchers hope that by examining the physiological and neural response mechanisms associated with acute stress … Read more