Astragaloside IV ameliorates peritoneal fibrosis by promoting PGC-1α to reduce apoptosis in vitro and in vivo

Icariin attenuates oxidative stress via SIRT1/PGC-1α pathway in SAH mice

Oxidative stress plays a pivotal role in the pathological response of subarachnoid hemorrhage (SAH). Icariin (ICA), with its potent antioxidant properties, exerts neuroprotective effects in stroke. This study investigated the beneficial effects of ICA on SAH-induced oxidative damage and its possible molecular mechanisms. The results indicated that ICA treatment improved both short-term and long-term neurobehavioral functions in mice with SAH. ICA significantly inhibited SAH-induced reactive oxygen species (ROS) generation and lipid peroxidation. Simultaneously, ICA restored the activity of the endogenous antioxidant enzyme system. Furthermore, ICA mitigated mitochondrial damage, improved mitochondrial morphology, further reduced neuronal apoptosis, and decreased brain edema following SAH. Mechanistically, ICA suppressed oxidative stress after SAH by activating Sirtuin 1 (SIRT1), subsequently upregulating the expression of PGC-1α. The SIRT1 inhibitor EX527 significantly inhibited ICA-induced SIRT1 activation and abolished the antioxidant and neuroprotective effects of ICA. In cellular experiments, ICA also inhibited ROS production and enhanced cell viability. These effects were associated with SIRT1 activation and were reversed by EX527 treatment. In conclusion, this study explored the protective effects of ICA against SAH-induced oxidative damage, suggesting that ICA could be a potential therapeutic agent for SAH.

Integrated serum metabolomics and network pharmacology reveal molecular mechanism of Qixue Huazheng formula on peritoneal fibrosis

Background

Peritoneal fibrosis (PF) causes peritoneal dialysis (PD) withdrawal due to ultrafiltration failure. Qixue Huazheng formula (QXHZF), comprising Astragalus membranaceus, Centella asiatica, and Ligusticum sinense, is applied to treat PD-related peritoneum injury related; however, the active components, core genes, and underlying mechanism involved remain unclear.

Methods

The anti-PF effects of QXHZF were verified in vivo and in vitro. Targets underlying QXHZF-mediated improvement of PD-induced PF were predicted using network pharmacology analysis. Metabolites associated with QXHZF treatment of PD-related PF were analyzed by serum metabolomics. Integration of network pharmacology and serum metabolomics findings identified potentially important pathways, metabolites, and targets, and molecular docking studies confirmed the interactions of key components and targets. Western blotting (WB), quantitative real-time PCR (qRT-PCR), TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, and flow cytometry were conducted.

Results

QXHZF had potent therapeutic efficacy against PF according to WB, qRT-PCR, and pathological section examination. Network pharmacological analysis indicated that multiple QXHZF compounds contributed to improving PF by modulating various targets and pathways. Differential metabolites were identified by serum metabolomics analysis. Integrated data analysis indicated that steroid hormone biosynthesis, the Ras signaling pathway, apoptosis, and estrogen signaling contributed to the effects of QXHZF. Metabolite-target network and molecular docking analyses revealed that QXHZF can bind to estrogen receptor 1 (ESR1) and rapidly accelerated fibrosarcoma 1 (RAF1) through its components. WB demonstrated that QXHZF treatment reversed activation of the above-mentioned signaling pathways, thereby inhibiting PD fluid-induced PF.

Conclusion

QXHZF can significantly ameliorate PD-induced PF and may regulate estrogen signaling, the Ras pathway, and apoptosis in this context.

BET Protein Inhibitor JQ1 Ameliorates Experimental Peritoneal Damage by Inhibition of Inflammation and Oxidative Stress

Peritoneal dialysis (PD) is a current replacement therapy for end-stage kidney diseases (ESKDs). However, long-term exposure to PD fluids may lead to damage of the peritoneal membrane (PM) through mechanisms involving the activation of the inflammatory response and mesothelial-to-mesenchymal transition (MMT), leading to filtration failure. Peritoneal damage depends on a complex interaction among external stimuli, intrinsic properties of the PM, and subsequent activities of the local innate-adaptive immune system. Epigenetic drugs targeting bromodomain and extra-terminal domain (BET) proteins have shown beneficial effects on different experimental preclinical diseases, mainly by inhibiting proliferative and inflammatory responses. However the effect of BET inhibition on peritoneal damage has not been studied. To this aim, we have evaluated the effects of treatment with the BET inhibitor JQ1 in a mouse model of peritoneal damage induced by chlorhexidine gluconate (CHX). We found that JQ1 ameliorated the CHX-induced PM thickness and inflammatory cell infiltration. Moreover, JQ1 decreased gene overexpression of proinflammatory and profibrotic markers, together with an inhibition of the nuclear factor-κB (NF-κB) pathway. Additionally, JQ1 blocked the activation of nuclear factor erythroid 2-related factor 2 (NRF2) and restored changes in the mRNA expression levels of NADPH oxidases (NOX1 and NOX4) and NRF2/target antioxidant response genes. To corroborate the in vivo findings, we evaluated the effects of the BET inhibitor JQ1 on PD patients' effluent-derived primary mesothelial cells and on the MeT-5A cell line. JQ1 inhibited tumor necrosis factor-α (TNF-α)-induced proinflammatory gene upregulation and restored MMT phenotype changes, together with the downmodulation of oxidative stress. Taken together, these results suggest that BET inhibitors may be a potential therapeutic option to ameliorate peritoneal damage.