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Mouhi, S.

Publications and source records attributed to Mouhi, S..

2 recordsLinked to original sources

Human spinal cord organoids recapitulate developmental and disease-associated oligodendrocyte lineage signatures

Oligodendrocytes play essential roles in central nervous system development and homeostasis, and their dysfunction is a hallmark of numerous neurological disorders. However, human in vitro systems that support oligodendrocyte lineage progression while enabling the study of disease-relevant states remain limited. Here, we establish human spinal cord organoids (hSpO) and cortico-motor assembloids as platforms to model oligodendrocyte development, neuron-glia interactions, and cytokine-induced dysfunction. We show that hSpO generate oligodendrocyte lineage populations that transcriptionally resemble those found in the developing human spinal cord, and oligodendrocyte progenitor cells that exhibit physiologically-relevant functional properties, including migration and monosynaptic input from neurons. Exposure of assembloids to pro-inflammatory cytokines induces transcriptional changes across the oligodendrocyte lineage, characterized by altered lineage progression and acquisition of disease-associated gene expression programs that mirror signatures observed in multiple sclerosis patient tissue. Together, this work establishes hSpO and assembloids as in vitro systems for studying oligodendrocyte lineage development and disease-associated states in a human multi-cellular context.

cell biology↗

The pyrethroid insecticide deltamethrin disrupts neuropeptide and monoamine signaling pathways in the gastrointestinal tract

Enteroendocrine cells (EECs) are a rare cell type of the intestinal epithelium. Various subtypes of EECs produce distinct repertoires of monoamines and neuropeptides which modulate intestinal motility and other physiologies. EECs also possess neuron-like properties, suggesting a potential vulnerability to ingested environmental neurotoxicants. One such group of toxicants are pyrethroids, a class of prevalent insecticides used residentially and agriculturally. Pyrethroids agonize voltage-gated sodium channels (VGSCs), inducing neuronal excitotoxicity, and affect the function of monoamine-producing neurons. Given their anatomical location at the interface with the environment and their expression of VGSCs, EECs likely represent a vulnerable cell-type to oral pyrethroid exposure. In this study, we used the EEC cell line, STC-1 cells, to evaluate the effects of the common pyrethroid deltamethrin on the functional status of EECs. We find that deltamethrin impacts both expression of serotonergic pathways and inhibits the adrenergic-evoked release of an EEC hormone, GLP-1, in vitro. In a mouse model of oral exposure, we found that deltamethrin induced an acute, yet transient, loss of intestinal motility, in both fed and fasted conditions. This constipation phenotype was accompanied by a significant decrease in peripheral serotonin production and an inhibition of nutrient-evoked intestinal hormone release. Together, these data demonstrate that deltamethrin alters monoaminergic signaling pathways in EECs and regulates intestinal motility. This work demonstrates a mechanistic link between pyrethroid exposure and intestinal impacts relevant to pyrethroid-associated diseases, including inflammatory bowel disease, neurodegenerative disease, and metabolic disorders.

pharmacology and toxicology↗