Acetic acid triggers cytochrome c release in yeast heterologously expressing human Bax

Forsythiaside A ameliorates bleomycin-induced pulmonary fibrosis by inhibiting oxidative stress and apoptosis

BACKGROUND

Pulmonary fibrosis (PF) is a common clinically critical disease characterized by high morbidity and high mortality. Forsythiaside A (FA) is a phenylethanol glycoside component in Forsythia suspensa, which has anti-inflammatory, antioxidant, and antiviral activities. However, the effects of FA on bleomycin (BLM)-induced PF are unclear.

PURPOSE

The present study explored the role of FA in the amelioration of oxidative stress and apoptosis in BLM-induced PF as well as the possible underlying mechanisms, in vivo and in vitro.

METHODS

Network pharmacology was used to collect the effects of FA on BLM-induced PF. Subsequently, further observation of the effects of FA on mice with PF by pulmonary pathological changes, transmission electron microscopy, real-time polymerase chain reaction, Western blot analysis, immunofluorescence, and immunohistochemistry. An in vitro model was constructed by inducing A549 with transforming growth factor beta-1 (TGF-β1) to observe the effect of FA on epithelial cell apoptosis.

RESULTS

Network pharmacology predicted signaling pathways such as IL-17 signaling pathway and Relaxin signaling pathway. The results of in vivo studies showed that FA ameliorated BLM-induced PF through inhibition of fibrosis, modulation of apoptosis, and oxidative stress. In addition, FA promoted TGF-β1-induced apoptosis in A549 cells.

CONCLUSIONS

The results of our study suggested that FA could protect mice against BLM-induced PF by regulating oxidative stress and apoptosis as well as the Epithelial mesenchymal transition pathway.

Paeonia lactiflora Pall. ameliorates acetaminophen-induced oxidative stress and apoptosis via inhibiting the PKC-ERK pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Paeonia lactiflora Pall. (PLP), a traditional Chinese medicine, is recognized for its antioxidative and anti-apoptotic properties. Despite its potential medicinal value, the mechanisms underlying its efficacy have been less explored, particularly in alleviating acute liver injury (ALI) caused by excessive intake of acetaminophen (APAP).

AIM OF THE STUDY

This study aims to elucidate the role and mechanisms of PLP in mitigating oxidative stress and apoptosis induced by APAP.

MATERIALS AND METHODS

C57BL/6 male mice were pre-treated with PLP for seven consecutive days, followed by the induction of ALI using APAP. Liver pathology was assessed using HE staining. Serum indicators, immunofluorescence (IF), immunohistochemical (IHC), and transmission electron microscopy were employed to evaluate levels of oxidative stress, ferroptosis and apoptosis. Differential expression proteins (DEPs) in the APAP-treated and PLP pre-treated groups were analyzed using quantitative proteomics. Subsequently, the potential mechanisms of PLP pre-treatment in treating ALI were validated using western blotting, molecular docking, molecular dynamics simulations, and surface plasmon resonance (SPR) analysis.

RESULTS

The UHPLC assay confirmed the presence of three compounds, i.e., albiflorin, paeoniflorin, and oxypaeoniflorin. Pre-treatment with PLP was observed to ameliorate liver tissue pathological damage through HE staining. Further confirmation of efficacy of PLP in alleviating APAP-induced liver injury and oxidative stress was established through liver function serum biochemical indicators, IF of reactive oxygen species (ROS) and IHC of glutathione peroxidase 4 (GPX4) detection. However, PLP did not demonstrate a significant effect in alleviating APAP-induced ferroptosis. Additionally, transmission electron microscopy and TUNEL staining indicated that PLP can mitigate hepatocyte apoptosis. PKC-ERK pathway was identified by proteomics, and subsequent molecular docking, molecular dynamics simulations, and SPR verified binding of the major components of PLP to ERK protein. Western blotting demonstrated that PLP suppressed protein kinase C (PKC) phosphorylation, blocking extracellular signal-regulated kinase (ERK) phosphorylation and inhibiting oxidative stress and cell apoptosis.

CONCLUSION

This study demonstrates that PLP possesses hepatoprotective abilities against APAP-induced ALI, primarily by inhibiting the PKC-ERK cascade to suppress oxidative stress and cell apoptosis.

COG1410 regulates microglial states and protects retinal ganglion cells in retinal ischemia-reperfusion injury

Progressive loss of retinal ganglion cells (RGCs) caused by retinal ischemia-reperfusion (IR) injury can lead to irreversible vision impairment, with neuroinflammatory responses playing an important role in this process. COG1410, a mimetic peptide of apolipoprotein E, has demonstrated protective potential in the central nervous system, but its effects on retinal IR injury remain unexplored. In this study, we established a mouse model of retinal IR injury to investigate the effects of COG1410 on retinal microglia and RGCs. We observed CD16/32-marked and CD206-marked microglia and RGCs using immunofluorescence staining, detected the expression of inflammatory factors by PCR, and evaluated retinal apoptosis with TUNEL staining. We further investigated the potential mechanism by detecting the expression of key proteins via Western blot. The results reveal that COG1410 decreased the number of CD16/32-marked microglia and increased the number of CD206-marked microglia, alleviated the expression of IL-1β and TNF-α, and reduced the loss of RGCs by inhibiting the mitochondrial-related apoptotic pathway. COG1410 was found to increase the expression of ERK1/2 and Nr4a1 but decrease the expression of NF-κB. The expression of TREM2 showed an increasing trend after COG1410 administration, but it was not statistically significant. In conclusion, COG1410 regulates microglial states and protects RGCs in retinal IR injury, showing promising potential for the treatment of eye diseases.

Pregabalin Mediates Retinal Ganglion Cell Survival From Retinal Ischemia/Reperfusion Injury Via the Akt/GSK3β/β-Catenin Signaling Pathway

Purpose

Progressive retinal ganglion cell (RGC) loss induced by retinal ischemia/reperfusion (RIR) injury leads to irreversible visual impairment. Pregabalin (PGB) is a promising drug for neurodegenerative diseases. However, with regard to RGC survival, its specific role and exact mechanism after RIR injury remain unclear. In this study, we sought to investigate whether PGB could protect RGCs from mitochondria-related apoptosis induced by RIR and explore the possible mechanisms.

Methods

C57BL/6J mice and primary RGCs were pretreated with PGB prior to ischemia/reperfusion modeling. The retinal structure and cell morphology were assessed by immunochemical assays and optical coherence tomography. CCK8 was used to assay cell viability, and an electroretinogram was performed to detect RGC function. Mitochondrial damage was assessed by a reactive oxygen species (ROS) assay kit and transmission electron microscopy. Western blot and immunofluorescence assays quantified the expression of proteins associated with the Akt/GSK3β/β-catenin pathway.

Results

Treatment with PGB increased the viability of RGCs in vitro. Consistently, PGB preserved the normal thickness of the retina, upregulated Bcl-2, reduced the ratio of cleaved caspase-3/caspase-3 and the expression of Bax in vivo. Meanwhile, PGB improved mitochondrial structure and prevented excessive ROS production. Moreover, PGB restored the amplitudes of oscillatory potentials and photopic negative responses following RIR. The mechanisms underlying its neuroprotective effects were attributed to upregulation of the Akt/GSK3β/β-catenin pathway. However, PGB-mediated neuroprotection was suppressed when using MK2206 (an Akt inhibitor), whereas it was preserved when treated with TWS119 (a GSK3β inhibitor).

Conclusions

PGB exerts a protective effect against RGC apoptosis induced by RIR injury, mediated by the Akt/GSK3β/β-catenin pathway.