Roots of Astragalus propinquus Schischkin Regulate Transmembrane Iron Transport and Ferroptosis to Improve Cerebral Ischemia-Reperfusion Injury

Abstract

Background. The dried roots of the Astragalus propinquus Schischkin (RAP) plant, as a traditional Chinese medicine, has been widely used to treat stroke, cerebral ischemia, qi deficiency, and hypertension. Buyang Huanwu decoction is traditionally used to treat stroke in China for more than 200 years and has a significant effect on cerebral ischemia, and RAP is monarch medicine of Buyang Huanwu decoction. Therefore, this study was designed to observe the regulatory effect of RAP on transmembrane iron transporters and ferroptosis-related factors in cerebral ischemia-reperfusion injury (CIRI) in rats. Methods. Middle cerebral artery occlusion (MCAO) was used to block blood flow in the blood supply area of the middle cerebral artery in seventy male SD rats to induce focal CIRI to establish a rat model of CIRI. RAP was administered to explore the regulatory effect of RAP on iron transmembrane transport under the condition of CIRI. The infarct size was measured using 2,3,5-triphenyl-tetrazolium chloride (TTC) staining, the pathological structure of brain tissue was observed by HE staining, and neuronal injury was evaluated by Nissl staining after treatment. Then, changes in the iron transporters ferritin (Fn), ferritin heavy chain (FHC), ferritin light chain (FLC), transferrin (Tf), transferrin receptor (TfR), divalent metal transporter 1 (DMT1), L-type calcium channel (LTCC), transient receptor potential canonical 6 (TRPC6), and ferroportin 1 (FPN1) were observed by immunohistochemistry staining (IHC) and Western blotting. The expression of key factors of ferroptosis, including the membrane sodium-dependent cystine/glutamate antiporter System Xc− (System Xc−) light chain subunit (XCT) and heavy chain subunit (SLC3A2), glutathione peroxidase 4 (GPX4), nuclear factor erythroid 2-related factor (NRF2), heme oxygenase-1 (HO-1), and iron-responsive element-binding protein 2 (IREB2) in the brain tissues of rats was assessed by Western blotting. RAP decreased the infarct size and neuronal injury after CIRI in rats. Similarly, RAP treatment regulated the expression of iron transporters. As such, RAP was able to reduce the expression of Fn, FHC, FLC, Tf, TfR, DMT1, and TRPC6 and increase the expression of FPN1 through a Tf/TfR-independent pathway after CIRI in rats. Conclusion. RAP stimulation inhibited ferroptosis by regulating the expression of the key ferroptosis factors XCT, SLC3A2, GPX4, NRF2, HO-1, and IREB2. In conclusion, RAP regulates transmembrane iron transport and ferroptosis to improve CIRI.

Dysregulation of iron homeostasis and ferroptosis in sevoflurane and isoflurane associated perioperative neurocognitive disorders

“…I/R injury was alleviated via ferroptosis inhibitory effect of nuclear receptor coactivator 4 (NCOA4) deletion 73 . In other words, regulation of iron transporters may facilitate to balance iron homeostasis and thus inhibiting ferroptosis in brain 74 . In addition, iron chelators including deferiprone (DFP) or deferoxamine (DFO) can protect brain from ferroptosis by decreasing iron content and inhibiting the downstream pathways 75,76 .…”

“…73 In other words, regulation of iron transporters may facilitate to balance iron homeostasis and thus inhibiting ferroptosis in brain. 74 In addition, iron chelators including deferiprone (DFP) or deferoxamine (DFO) can protect brain from ferroptosis by decreasing iron content and inhibiting the downstream pathways. 75,76 In summary, regulating iron metabolism-related proteins or chelating iron accumulation in brain can inhibit Fenton reaction and present protective effect on ferroptosis-induced brain damage.…”

Progress of medicinal plants and their active metabolites in ischemia-reperfusion injury of stroke: a novel therapeutic strategy based on regulation of crosstalk between mitophagy and ferroptosis

“…The Bu Yang Huan Wu Tang, which has been used in traditional Chinese medicine to treat stroke for more than 200 years, has a significant effect on cerebral ischemia, with A. membranaceus as the main ingredient. Therefore, Chen J et al ( Chen et al, 2022 ) studied the regulation of A. membranaceus on transmembrane iron transport proteins and iron-related factors in rat cerebral ischemia reperfusion injury. They established a rat cerebral ischemia reperfusion injury model by using MCAO to block the blood supply of the bilateral cerebral middle cerebral artery in two male SD rats.…”

Pharmacological Inhibition of Ferroptosis as a Therapeutic Target for Neurodegenerative Diseases and Strokes

“…[ 247 ] At 14 days, the iron is enriched predominately at macrophages of the entire ischemic lesion core, suggesting that astrocytes and macrophages play a role in regulating iron after cerebral ischemia. Ferritin, [ 248 ] TFR1, [ 249 , 250 , 251 , 252 , 253 ] and DMT1 [ 250 , 252 ] which may contribute to the influx of iron, are also increased in ischemic stroke. Meanwhile, decreased iron efflux following ischemic stroke may also contribute to iron accumulation.…”