To investigate whether olfactory mucosa mesenchymal stem cells (OM-MSCs attenuate oxygen glucose deprivation and recovery (OGD/R)-induced ferroptosis in neurons through glutathione oxidase 4 (GPX4).

The middle nasal tissue were collected from a patient with nasal polyps admitted in our hospital, and then OM-MSCs were isolated from the tissue, which were confirmed by morphological observation under light microscopy and phenotypic characterization through flow cytometry for surface markers, including CD34, CD45, CD73, CD90, CD105, and CD146. Mouse hippocampal neuronal cell line HT22 was randomly divided into control, Control, OGD/R, OGD/R+OM-MSCs, OGD/R+sh-NC, OGD/R+sh-GPX4 and OGD/R+sh-GPX4+OM-MSCs groups. After the cells were subjected to OGD/R modeling, the cells were subsequently co-cultured with OM-MSCs and/or knockdown of GPX4. Neuronal apoptosis was quantified by flow cytometry, while cell viability was assessed using CCK-8 assay. Biochemical markers associated with ferroptosis, including MDA, ROS, GSH, and Fe²⁺ levels, were measured with corresponding reagent kits. The GPX4 expression at both mRNA and protein levels was determined through qPCR and Western blotting, respectively.

The isolated and primarily cultured OM-MSCs showed typical characteristics of OM-MSCs in cell surface markers (negative expression of CD34 and CD45 but positive expression of CD73, CD90, CD105, and CD146 on cell surface) and morphology (adherent cells in a spindle-like shape). Significant differences were observed among the control, OGD/R, and OGD/R+OM-MSCs groups in terms of cell viability, MDA, ROS, GSH, Fe²⁺ and GPX4 (P<0.05). The OGD/R group showed notable decreases in cell activity and GSH (P<0.05), increases in MDA, ROS, and Fe²⁺ (P<0.05), and down-regulation of GPX4 when compared with the control group (P<005). Co-culture with OM-MSCs enhanced cell activity and GSH (P<0.05), decreased MDA, ROS, and Fe²⁺ (P<0.05), and up-regulated GPX4 as compared to the conditions in the OGD/R group (P<0.05). While, OGD/R+sh-GPX4 treament developed the decreases in cell viability, GSH, and GPX4 and the increases in MDA, ROS, and Fe²⁺ as compared to the OGD/R+sh-NC group (P<0.05), however, all of these could be reversed by OM-MSCs.

OM-MSCs inhibit OGD/R-induced ferroptosis in HT22 cells by up-regulating GPX4.