Ginkgolide B attenuates cerebral ischemia-reperfusion injury via inhibition of ferroptosis through disrupting NCOA4-FTH1 interaction

Lactylation of nuclear receptor coactivator 4 promotes ferritinophagy and glycolysis of neuronal cells after cerebral ischemic injury

Ischemic stroke remains a major cause of disability and mortality. Nuclear receptor coactivator 4 (NCOA4)-mediated ferritinophagy is involved in cerebral ischemic injury. Additionally, lactylation regulates the progression of ischemia injury. This study aimed to investigate the impact of NCOA4 on ferritinophagy and glycolysis of hippocampal neuron cells and its lactylation modification. Middle cerebral artery occlusion (MCAO) mouse and oxygen-glucose deprivation (OGD)-treated HT22 cell models were generated. Ferritinophagy was evaluated via detecting ferrous iron (Fe 2+ ), glutathione, malondialdehyde, and protein levels. Glycolysis was assessed by examining the glucose consumption, lactate production, and extracellular acidification rate. The lactylation was evaluated using immunoprecipitation and immunoblotting. Brain injury in vivo was analyzed by measuring brain infarct and neurological function. The results showed that NCOA4 expression was increased in the blood of patients with acute ischemia stroke, the peri-infarct region of the brain in MCAO mice (increased percentage: 142.11%) and OGD-treated cells (increased percentage: 114.70%). Knockdown of NCOA4 inhibited ferritinophagy and glycolysis of HT22 cells induced by OGD. Moreover, OGD promoted the lactylation of NCOA4 at lysine (K)450 sites, which enhanced NCOA4 protein stability. Additionally, interfering with NCOA4 attenuated brain infarction and neurological dysfunction in MCAO mice. Lactylation of NCOA4 at K450 sites promotes ferritinophagy and glycolysis of hippocampal neuron cells, thereby accelerating cerebral ischemic injury. These findings suggest a novel pathogenesis of ischemic stroke.

Ferritinophagy and Ferroptosis in Cerebral Ischemia Reperfusion Injury

Cerebral ischemia-reperfusion injury (CIRI) is the second leading cause of death worldwide, posing a huge risk to human life and health. Therefore, investigating the pathogenesis underlying CIRI and developing effective treatments are essential. Ferroptosis is an iron-dependent mode of cell death, which is caused by disorders in iron metabolism and lipid peroxidation. Previous studies demonstrated that ferroptosis is also a form of autophagic cell death, and nuclear receptor coactivator 4(NCOA4) mediated ferritinophagy was found to regulate ferroptosis by interfering with iron metabolism. Ferritinophagy and ferroptosis are important pathogenic mechanisms in CIRI. This review mainly summarizes the link and regulation between ferritinophagy and ferroptosis and further discusses their mechanisms in CIRI. In addition, the potential treatment methods targeting ferritinophagy and ferroptosis for CIRI are presented, providing new ideas for the prevention and treatment of clinical CIRI in the future.

Ginsenoside Rg1 mitigates cerebral ischaemia/reperfusion injury in mice by inhibiting autophagy through activation of mTOR signalling

Reperfusion injury, which is distinct from ischaemic injury, occurs when blood flow is restored in previously ischaemic brain tissue, further compromising neurons and other cells and worsening the injury. There is currently a lack of pharmaceutical agents and therapeutic interventions that specifically mitigate cerebral ischaemia/reperfusion (I/R) injury. Ginsenoside Rg1 (Rg1), a protopanaxatriol-type saponin isolated from Panax ginseng C. A. Meyer, has been found to protect against cerebral I/R injury, but its intricate protective mechanisms remain to be elucidated. Numerous studies have shown that autophagy plays a crucial role in protecting brain tissue during the I/R process and is emerging as a promising therapeutic strategy for effective treatment. In this study, we investigated whether Rg1 protected against I/R damage in vitro and in vivo by regulating autophagy. Both MCAO and OGD/R models were established. SK-N-AS and SH-SY5Y cells were subjected to OGD followed by reperfusion with Rg1 (4-32 μM). MCAO mice were injected with Rg1 (30 mg·kg-1·d-1. i.p.) for 3 days before and on the day of surgery. Rg1 treatment significantly mitigated ischaemia/reperfusion injury both in vitro and in vivo. Furthermore, we demonstrated that the induction of autophagy contributed to I/R injury, which was effectively inhibited by Rg1 in both in vitro and in vivo models of cerebral I/R injury. Rg1 inhibited autophagy through multiple steps, including impeding autophagy initiation, inducing lysosomal dysfunction and inhibiting cathepsin enzyme activities. We revealed that mTOR activation was pivotal in mediating the inhibitory effect of Rg1 on autophagy. Treatment with Torin-1, an autophagy inducer and mTOR-specific inhibitor, significantly reversed the impact of Rg1 on autophagy, decreasing its protective efficacy against I/R injury both in vitro and in vivo. In conclusion, our results suggest that Rg1 may serve as a promising drug candidate against cerebral I/R injury by inhibiting autophagy through activation of mTOR signalling.

Ginkgo biloba: A Leaf of Hope in the Fight against Alzheimer's Dementia: Clinical Trial Systematic Review

Alzheimer's disease (AD) is a stealthy and progressive neurological disorder that is a leading cause of dementia in the global elderly population, imposing a significant burden on both the elderly and society. Currently, the condition is treated with medications that alleviate symptoms. Nonetheless, these drugs may not consistently produce the desired results and can cause serious side effects. Hence, there is a vigorous pursuit of alternative options to enhance the quality of life for patients. Ginkgo biloba (GB), an herb with historical use in traditional medicine, contains bioactive compounds such as terpenoids (Ginkgolides A, B, and C), polyphenols, organic acids, and flavonoids (quercetin, kaempferol, and isorhamnetin). These compounds are associated with anti-inflammatory, antioxidant, and neuroprotective properties, making them valuable for cognitive health. A systematic search across three databases using specific keywords-GB in AD and dementia-yielded 1702 documents, leading to the selection of 15 clinical trials for synthesis. In eleven studies, GB extract/EGb 761® was shown to improve cognitive function, neuropsychiatric symptoms, and functional abilities in both dementia types. In four studies, however, there were no significant differences between the GB-treated and placebo groups. Significant improvements were observed in scores obtained from the Mini-Mental State Examination (MMSE), Short Cognitive Performance Test (SKT), and Neuropsychiatric Inventory (NPI). While the majority of synthesized clinical trials show that Ginkgo biloba has promising potential for the treatment of these conditions, more research is needed to determine optimal dosages, effective delivery methods, and appropriate pharmaceutical formulations. Furthermore, a thorough assessment of adverse effects, exploration of long-term use implications, and investigation into potential drug interactions are critical aspects that must be carefully evaluated in future studies.

The anti-apoptotic role of Ginkgolide B via mitochondrial permeability transition pore inhibition in retinal ischemia-reperfusion

This research delves into the effectiveness of Ginkgolide B (GB), a compound from Ginkgo biloba, in combating cell death caused by glaucoma, with a focus on mitochondrial impairment and the mitochondrial permeability transition pore (mPTP). Utilizing models of high intraocular pressure and in vitro glaucoma simulations, the study investigates GB's impact on retinal progenitor cells (RPCs) under oxygen-glucose deprivation/reperfusion (OGD/R) and in a rat glaucoma model. The study methodologies included apoptosis assessment, apoptotic marker analysis via Western blot, and mitochondrial structure and function evaluation. The findings reveal that GB notably decreases apoptosis in RPCs exposed to OGD/R in vitro, and reduces ischemia-reperfusion damage in vivo. GB's protective role is attributed to its ability to preserve mitochondrial integrity, maintain membrane potential, regulate calcium levels, and inhibit mPTP opening. These results underscore GB's potential as a therapeutic agent for acute primary angle-closure glaucoma, highlighting its capability to alleviate mitochondrial damage and apoptosis in RPCs and retinal nerve fiber layer cells.

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 death of cells can occur through various pathways, including apoptosis, necroptosis, mitophagy, pyroptosis, endoplasmic reticulum stress, oxidative stress, ferroptosis, cuproptosis, and disulfide-driven necrosis. Increasing evidence suggests that mitophagy and ferroptosis play crucial regulatory roles in the development of stroke. In recent years, the incidence of stroke has been gradually increasing, posing a significant threat to human health. Hemorrhagic stroke accounts for only 15% of all strokes, while ischemic stroke is the predominant type, representing 85% of all stroke cases. Ischemic stroke refers to a clinical syndrome characterized by local ischemic-hypoxic necrosis of brain tissue due to various cerebrovascular disorders, leading to rapid onset of corresponding neurological deficits. Currently, specific therapeutic approaches targeting the pathophysiological mechanisms of ischemic brain tissue injury mainly include intravenous thrombolysis and endovascular intervention. Despite some clinical efficacy, these approaches inevitably lead to ischemia-reperfusion injury. Therefore, exploration of treatment options for ischemic stroke remains a challenging task. In light of this background, advancements in targeted therapy for cerebrovascular diseases through mitophagy and ferroptosis offer a new direction for the treatment of such diseases. In this review, we summarize the progress of mitophagy and ferroptosis in regulating ischemia-reperfusion injury in stroke and emphasize their potential molecular mechanisms in the pathogenesis. Importantly, we systematically elucidate the role of medicinal plants and their active metabolites in targeting mitophagy and ferroptosis in ischemia-reperfusion injury in stroke, providing new insights and perspectives for the clinical development of therapeutic drugs for these diseases.

Endoplasmic Reticulum Stress Promotes Neuronal Damage in Neonatal Hypoxic-Ischemic Brain Damage by Inducing Ferroptosis

Hypoxic-ischemic brain damage (HIBD) poses a significant risk of neurological damage in newborns. This study investigates the impact of endoplasmic reticulum stress (ERS) on neuronal damage in neonatal HIBD and its underlying mechanisms. HIBD neonatal rat model was constructed and pre-treated with 4-phenylbutiric acid (4-PBA). Nissl and TUNEL staining were utilised to assess neuronal damage and apoptosis in rat brains. HIBD cell model was established by inducing oxygen-glucose deprivation (OGD) in rat H19-7 neurons, which were then pre-treated with Thapsigargin (TG), Ferrostatin-1 (Fer-1), or both. Cell viability and apoptosis of H19-7 neurons were analysed using cell counting kit-8 assay and TUNEL staining. GRP78-PERK-CHOP pathway activity and glutathione peroxidase-4 (GPX4) expression in rat brains and H19-7 neurons were assessed using Western blot. Ferroptosis-related indicators, including glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (MDA) and iron content, were measured using commercial kits in both rat brains and H19-7 neurons. GRP78-PERK-CHOP pathway was overactivated in HIBD neonatal rats' brains, which was mitigated by 4-PBA treatment. 4-PBA treatment demonstrated a reduction in neuronal damage and apoptosis in HIBD-affected neonatal rat brains. Furthermore, it attenuated ferroptosis in rats by increasing GPX4, GSH and SOD while decreasing MDA and iron content. In the OGD-induced H19-7 neurons, Fer-1 treatment counteracted the suppressive effects of TG on viability, the exacerbation of apoptosis, the promotion of ferroptosis and the activation of the GRP78-PERK-CHOP pathway. Overall, ERS facilitates neuronal damage in neonatal HIBD by inducing ferroptosis. Consequently, the suppression of ERS may represent a promising therapeutic strategy for treating neonatal HIBD.