Bone marrow mesenchymal stem cells with PTBP1 knockdown protect against cerebral ischemia-reperfusion injury by inhibiting ferroptosis via the JNK/P38 pathway in rats.

PTBP1KD-BMSCs can reduce the cerebral infarction volume, neurological function score, and improve neuronal damage in rats with ischemia–reperfusion, which is attributed to the down-regulation of PTBP1 , which inhibits the proliferation of BMSCs, slows down cell aging, and enhances cell viability. PTBP1KD-BMSCs may play a protective role in regulating ferroptosis by inhibiting the JNK/P38 pathway to increase the antioxidant activity and inhibit lipid peroxidation in neurons with ischemia–reperfusion injury. [Display omitted] • PTBP1KD-BMSCs treat ischemia–reperfusion injury in neurons. • PTBP1 regulates the BMSC cell cycle and increases cell viability. • PTBP1KD-BMSCs conditioned medium protects PC12 cells from OGD/R. • It inhibits ferroptosis and regulates the P38/JNK pathway in PC12 cells. Over the years, the neuroprotective potential of bone marrow mesenchymal stem cells (BMSCs) in acute ischemic stroke has attracted significant attention. However, BMSCs face challenges like short metabolic cycles and low survival rates post-transplant. Polypyrimidine tract-binding protein 1 (PTBP1) is an immunomodulatory RNA-binding protein that regulates the cell cycle and increases cell viability. This study investigated the protective effects and underlying mechanism of PTBP1 knockdown in BMSCs (PTBP1KD-BMSCs) following ischemia–reperfusion injury (IRI) in neurons. BMSCs were isolated from Sprague-Dawley rat femurs and characterized through flow cytometry and differentiation induction. PTBP1 knockdown inhibited BMSCs proliferation. Co-culture with PTBP1KD-BMSCs decreased reactive oxygen species (ROS) and malondialdehyde (MDA) levels, while increasing glutathione (GSH) production in oxygen and glucose deprivation/reperfusion-induced PC12 cells. Transcriptome sequencing analysis of PC12 cells suggested that the protective effect of PTBP1KD-BMSCs against injury may involve ferroptosis. Furthermore, western blotting showed upregulation of glutathione synthetase (GSS), glutathione peroxidase 4 (GPX4), and solute carrier family 7 member 11 (SLC7A11) in PTBP1KD-BMSCs, known negative regulators of ferroptosis. Moreover, PTBP1KD-BMSCs inhibited p38MAPK and JNK activation. In addition, PTBP1KD-BMSCs transplantation into middle cerebral artery occlusion/reperfusion (MCAO/R) rats reduced cerebral infarction volume and improved neurological function. Immunofluorescence analysis confirmed the upregulation of GSS expression in neurons of the ischemic cortex, while immunohistochemistry indicated a downregulation of p-P38. These result suggest that PTBP1KD-BMSCs can alleviate neuronal IRI by reducing oxidative stress, inhibiting ferroptosis, and modulating the MAPK pathway, providing a theoretical basis for potential treatment strategies for cerebral IRI. [ABSTRACT FROM AUTHOR]