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Molet, J.

Publications and source records attributed to Molet, J..

2 recordsLinked to original sources

A receptor-independent signaling pathway for BDNF

In addition to its well-known receptor-mediated function in cell survival, differentiation and growth, we report that the extracellular brain-derived neurotrophic factor (BDNF) also controls the intracellular KEAP1-NRF2 cytoprotective system by a receptor-independent pathway. Extracellular BDNF can cross the cell membrane as it possesses a protein-translocation domain, also known as cell-penetrating peptide. This membrane crossing process is energy-independent, ruling out endocytosis and receptor-dependent mechanisms. Once in the cytosol, BDNF binds to KEAP1 with a nanomolar affinity, enabling nuclear translocation of NRF2 and transcription of NRF2-target genes. BDNF is thus a major regulator of NRF2 activation. A dysfunction of this BDNF-KEAP1-NRF2 pathway may be involved in most diseases where antioxidant and cytoprotective functions are altered. This novel form of communication, whereby a receptor ligand protein exerts a biological activity by crossing the cell membrane, opens new avenues for cell signaling.

cell biology↗

On the origins of a selective vulnerability to opioid addiction.

The origins and neural bases of the current opioid addiction epidemic are unclear. Genetics plays a major role in addiction vulnerability, but cannot account for the recent exponential rise in opioid abuse, so environmental factors must contribute. Individuals with history of early-life adversity (ELA) are disproportionately prone to opioid addiction, yet whether ELA interacts with factors such as increased access to opioids to directly influence brain development and function and cause opioid addiction vulnerability is unknown. We simulated ELA in female rats and this led to a striking opioid addiction-like phenotype. This was characterized by resistance to extinction, increased relapse-like behavior, and, as in addicted humans, major increases in opioid economic demand. By contrast, seeking of a less salient natural reward was unaffected by ELA, whereas demand for highly palatable treats was augmented. These discoveries provide novel insights into the origins and nature of reward circuit malfunction that may set the stage for addiction.

neuroscience↗