Valdecoxib Protects against Cell Apoptosis Induced by Endoplasmic Reticulum Stress via the Inhibition of PERK-ATF4-CHOP Pathway in Experimental Glaucoma.

The purpose of this study was to investigate the effects of valdecoxib on the retina in retinal ischemia-reperfusion injury (IRI) and R28 cells following oxygen-glucose deprivation/recovery (OGD/R) injury, as well as the underlying mechanisms. Immunofluorescence and Cell Counting Kit-8 (CCK-8) analyses were used to identify the proper timepoint and concentration of valdecoxib's protective effect on the R28 cells in the OGD/R model. Hematoxylin-eosin (HE) staining and immunofluorescence were used to explore valdecoxib's effect on the retina and retina ganglion cell (RGC) in IRI. Cell apoptosis was determined by a TUNEL Apoptosis Detection Kit and Annexin V-FITC/PI flow cytometry. The expression levels of p-PERK, transcription factor 4 (ATF4), GRP78, CHOP, cleaved caspase 3, bax and bcl-2 were measured by Western blot analyses. The valdecoxib protected the R28 cells from OGD/R injury by decreasing the cell apoptosis rate, and it exerted a protective effect on retinas in I/R injury by inhibiting RGC apoptosis. The valdecoxib pretreatment reversed the expression of p-PERK, ATF4, CHOP, GRP78, cleaved caspase 3 and bax induced by the glaucomatous model. Meanwhile, the CCT020312 reversed the valdecoxib's anti-apoptosis effect by activating PERK-ATF4-CHOP pathway-mediated endoplasmic reticulum (ER) stress. These findings suggest that valdecoxib protects against glaucomatous injury by inhibiting ER stress-induced apoptosis via the inhibition of the PERK-ATF4-CHOP pathway.

Microglia are necessary for probiotics supplementation to improve impaired fear extinction caused by pregnancy stress in adult offspring of rats.

The prevention and treatment of fear-related disorders in offspring affected by pregnancy stress remains challenging at clinic. Here, we examined the effects of gut microbiota of stressed pregnant rats on the fear extinction of their offsprings, and the potential mechanisms. We found that gut microbiota transplantation from rats with pregnancy stress to normal pregnant rats impaired fear extinction, induced microglial activation and synaptic phagocytosis, increased synapse loss in offsprings. Probiotics supplement during pregnancy stress partly normalized pregnancy stress-induced gut microbiota dysbiosis of pregnant rats, and promoted fear memory extinction, inhibited fear memory reappearance, and limited microglial activation and synaptic phagocytosis in offsprings. These data revealed that gut microbiota of stressed pregnant mother improved the development of fear-related disorders of offspring, which may be associated with microglial synaptic pruning.