Nutlin-3

Glaucoma is a neurodegenerative disease characterized by the progressive and irreversible loss of retinal ganglion cells (RGCs). Elevated intraocular pressure (IOP) is a key factor in initiating pathological processes in acute glaucoma. This study aims to investigate the role of TRPV4 in mediating retinal inflammatory damage following acute glaucomatous injury. Using an in vitro elevated hydrostatic pressure (EHP) model established in BV2 microglia and an in vivo acute ocular hypertension (AOH) model in mice, we assessed microglial migration and polarization (M1/M2), lipid peroxidation, mitochondrial morphology, ferroptosis-related protein expression, and retinal ganglion cell survival. The function of TRPV4 was validated using the specific inhibitor HC-067047 and TRPV4 gene knockdown, and the p53/SLC7A11/GPX4 ferroptosis axis was investigated using the ferroptosis inhibitor Ferrostatin-1 (Fer-1), the p53 agonist Nutlin-3, and p53 gene knockdown. Results demonstrated that injury upregulates and activates TRPV4, inducing calcium influx in microglia. TRPV4 activation triggered ferroptosis by upregulating p53 and downregulating SLC7A11 and GPX4, thereby promoting pro-inflammatory M1 microglial polarization and exacerbating ganglion cell injury. Notably, pharmacological inhibition of TRPV4 reversed these responses, shifting microglia toward an anti-inflammatory M2 phenotype and mitigating ganglion cell loss. These findings demonstrate that TRPV4 activation drives ferroptosis via the p53/SLC7A11/GPX4 axis, thereby promoting microglial-mediated neuroinflammation, providing a new theoretical perspective for understanding the pathogenesis of neuroinflamation in glaucoma.

To investigate the neuroprotective effect of gastrodin (GAS) against hypobaric hypoxia (HH)-induced brain injury in rats and the underlying mechanism.

Twenty-four adult SD rats were randomized equally into normoxic control group, HH model group, low-dose (100 mg/kg) GAS group (HH+GAS-L group), and high-dose (200 mg/kg) GAS group (HH+GAS-H group). In the latter 3 groups, the rats were exposed to HH in a hypobaric oxygen chamber for 24 h to simulate the condition at an altitude of 6000 m, and GAS was administered intraperitoneally once daily for 7 days. Cerebral cortex tissues were collected for analysis of P53, SLC7A11, and GPX4 protein expressions using Western blotting and for determination of the levels of reactive oxygen species (ROS), malondialdehyde (MDA), glutathione (GSH), and ferrous ion (Fe²⁺). In cultured HT22 neurons exposed to oxygen-glucose deprivation (OGD), the effects of GAS (500 μmol/L), nutlin-3 (a P53 agonist; 10 μmol/L) or their combination were examined on ferroptosis-related protein expressions, intracellular ROS, lipid peroxidation, MDA, GSH, cell viability, mitochondrial membrane potential, and Fe²⁺ levels.

In the rat models of HH, GAS treatment significantly inhibited P53 expression, upregulated SLC7A11 and GPX4 proteins, markedly reduced Fe²⁺, ROS, and MDA levels, and increased GSH content in the cerebral cortex. In cultured HT22 neurons, GAS treatment effectively alleviated OGD-induced cell ferroptosis as shown by decreased P53 expression, increased SLC7A11 and GPX4 expressions, and lowered levels of intracellular ROS generation, lipid peroxidation, and Fe²⁺ accumulation, along with obvious restoration of GSH levels, cell viability, and mitochondrial membrane potential. The protective effects of GAS was markedly attenuated by activation of the P53 pathway using nutlin-3.

GAS produces neuroprotective effects against HH-induced brain injury in rats by inhibiting neuronal ferroptosis via regulating the P53/SLC7A11/GPX4 signaling pathway.