Hederagenin protects against myocardial ischemia-reperfusion injury via attenuating ALOX5-mediated ferroptosis

Perillaldehyde protect chondrocytes from mitophagy-associated apoptosis and NLRP3-mediated inflammation by regulating ALOX5/NF-kB signaling in osteoarthritis

BACKGROUND

Osteoarthritis (OA) is an age-related progressive joint disease characterized by loss of cartilage and subsequent inflammation. Perillaldehyde is a compound extracted from Perilla, which has multiple pharmacological activities including anti-inflammatory, and anti-apoptosis. However, it still remains unknown whether and how perillaldehyde could regulate chondrocyte apoptosis and inflammation in OA.

METHODS

The interleukin-1beta (IL-1β)-treated chondrocytes and destabilized medial meniscus (DMM) -induced rats were used as in vitro and in vivo models of OA. Cell viability, proliferation, and apoptosis were investigated by cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assays. The mitochondrial membrane potential was analyzed by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining. Light chain 3 (LC3) location, and expression of NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) and apoptosis-associated speck-like protein (ASC) were detected by immunofluorescence staining. Relative protein levels were measured via western blotting. Tumor necrosis factor-alpha (TNF-α), IL-6 and IL-8 levels were measured by enzyme-linked immunosorbent assay (ELISA). The cartilage injury in rats was investigated via hematoxylin-eosin (HE) staining.

RESULTS

Perillaldehyde attenuated IL-1β-induced inhibition of viability (from 44.45 % to 92.72 %, p < 0.05) and proliferative potential of chondrocytes (p < 0.05). Perillaldehyde mitigated mitophagy-associated apoptosis of chondrocytes by enhancing mitophagy (p < 0.05) and reducing cell apoptosis (from 32.36 % to 8.00 %, p < 0.05). Perillaldehyde attenuated NLRP3-mediated inflammation through reducing NLRP3, ASC, TNF-α, IL-6 and IL-8 levels (p < 0.05). ALOX5 expression was upregulated in OA (fold change: 2.61, p < 0.05), and decreased by perillaldehyde treatment (fold change: 1.34, p < 0.05). Perillaldehyde inhibits p65 nuclear factor kappa B (NF-κB) signaling activation (fold change: 3.19 to 1.33, p < 0.05) by regulating ALOX5 expression. ALOX5 overexpression reversed the effects of perillaldehyde on mitophagy-associated apoptosis and NLRP3-mediated inflammation (p < 0.05), and these roles were mitigated due to NF-κB inactivation (p < 0.05). Perillaldehyde attenuated cartilage injury in OA rats (p < 0.05).

CONCLUSION

Perillaldehyde attenuated IL-1β-induced mitophagy-associated apoptosis and NLRP3-mediated inflammation through decreasing ALOX5 and inactivating NF-κB signaling, indicating the potentially protective potential of perillaldehyde in osteoarthritis.

Diselenide Nanogels Modulate Mitochondrial Function and Mitigate Oxidative Stress in Cardiomyocytes for Enhanced Cardiac Repair

Mitochondrial dysfunction and oxidative stress are pivotal factors contributing to the loss of cardiac function following heart injury, yet these aspects are frequently underappreciated in the medication design paradigm. Here we have developed diselenide-cross-linked zwitterionic nanogels to restore mitochondrial homeostasis and boost energy supply for damaged heart repair. These nanogels exhibit an enhanced circulation time within the bloodstream post systemic administration and have been observed to concentrate at the site of the damaged myocardium in both myocardial infarct (MI) rat model and cardiotoxic mouse model. Our mechanistic investigations have revealed that these nanogels have the capacity to mitigate the oxidative microenvironment, thereby preserving the mitochondrial function of cardiomyocytes. Moreover, the degradation products of these nanogels have been shown to upregulate intracellular ATP synthesis, which in turn increases cardiac contractility and promotes the recovery of cardiac function. The innovative nanogel system presented herein holds significant potential for clinical translation, offering a therapeutic strategy for the restoration of cardiac function and a fresh perspective on maintaining energy metabolism homeostasis in the treatment of heart injury.

Hederagenin ameliorates ferroptosis-induced damage by regulating PPARα/Nrf2/GPX4 signaling pathway in HT22 cells: An in vitro and in silico study

BACKGROUND

Hederagenin (HG), derived from ivy seeds, is known to offer protection against Alzheimer's disease (AD). However, the specific molecular pathways through which it counters ferroptosis-induced neurotoxicity are not fully elucidated. This investigation seeks to delineate the processes by which HG mitigates neurotoxic effects in HT22 cells subjected to glutamate (Glu)-induced ferroptosis.

METHODS

HT22 cell ferroptosis was prompted by Glu exposure. Cell viability was assessed using CCK-8 and LDH assays, while Fe2+ fluorescence and assays of iron-related proteins served to gauge intracellular Fe2+ concentrations. Evaluations of mitochondrial structure and functionality employed JC-1 staining and transmission electron microscopy. Assessments of ROS, lipid peroxidation, MDA, 4-HNE, and the GSSG/GSH ratio were conducted to ascertain HG's antioxidative efficacy. The expression of proteins within the PPARα/Nrf2/GPX4 pathway was quantified via western blotting, with molecular docking (MD), and molecular dynamics simulations (MDS) used to explore protein interactions.

RESULTS

HG diminished the cellular toxicity triggered by Glu in HT22 cells, lowered Fe2+ within cells, and rejuvenated mitochondrial morphology and performance. Concurrently, it modulated proteins critical to Fe2+ metabolism, diminished ROS and lipid peroxidation, and elevated GSH/GSSG ratios. Enhanced PPARα/Nrf2/GPX4 protein levels were corroborated by western blot results. Furthermore, molecular docking revealed favorable binding of HG to the proteins PPARα, Nrf2, and GPX4, with binding energies of -7.751, -7.535, and -7.414 kcal/mol, respectively. MDS confirmed robust interactions between HG and these pivotal targets.

CONCLUSION

The evidence suggests that HG effectively mitigates Glu-induced ferroptosis in HT22 cells by activating the PPARα/Nrf2/GPX4 signaling pathway. These findings endorse HG's potential as a nutritional adjunct for AD management.

An emerging double‑edged sword role of ferroptosis in cardiovascular disease (Review)

The pathophysiology of cardiovascular disease (CVD) is complex and presents a serious threat to human health. Cardiomyocyte loss serves a pivotal role in both the onset and progression of CVD. Among various forms of programmed cell death, ferroptosis, along with apoptosis, autophagy and pyroptosis, is closely linked to the advancement of CVD. Ferroptosis, a mechanism of cell death, is driven by the buildup of oxidized lipids and excess iron. This pathway is modulated by lipid, amino acid and iron metabolism. Key characteristics of ferroptosis include disrupted iron homeostasis, increased peroxidation of polyunsaturated fatty acids due to reactive oxygen species, decreased glutathione levels and inactivation of glutathione peroxidase 4. Treatments targeting ferroptosis could potentially prevent or alleviate CVD by inhibiting the ferroptosis pathway. Ferroptosis is integral to the pathogenesis of several types of CVD and inhibiting its occurrence in cardiomyocytes could be a promising therapeutic strategy for the future treatment of CVD. The present review provided an in‑depth analysis of advancements in understanding the mechanisms underlying ferroptosis. The present manuscript summarized the interplay between ferroptosis and CVDs, highlighting its dual roles in these conditions. Additionally, potential therapeutic targets within the ferroptosis pathway were discussed, alongside the current limitations and future directions of these novel treatment strategies. The present review may offer novel insights into preventive and therapeutic approaches for CVDs.

Quercetin Alleviates LPS-Stimulated Myocardial Injury through Regulating ALOX5/PI3K/AKT Pathway in Sepsis

Quercetin (QUE) has been found to inhibit the progression of sepsis-related diseases, including sepsis-induced cardiomyopathy (SIC). More information about the role and mechanism of QUE in SIC progression deserves further exploration. Human cardiomyocytes (AC16) were induced with LPS to mimic SIC cell models. Cell proliferation and apoptosis were determined using CCK8 assay, EdU assay, and flow cytometry. Cell inflammation and ferroptosis were evaluated by detecting IL-1β, TNF-α, Fe2+, ROS, GSH, and GPX4 levels. 5-lipoxygenase (ALOX5) expression was examined by quantitative real-time PCR and western blot. LPS treatment reduced AC16 cell proliferation, while enhanced apoptosis, inflammation, and ferroptosis. QUE repressed LPS-induced AC16 cell apoptosis, inflammation, and ferroptosis. ALOX5 was upregulated in SIC patients, and its expression was reduced by QUE. ALOX5 knockdown restrained LPS-induced apoptosis, inflammation, and ferroptosis in AC16 cells. The inhibitory effect of QUE on LPS-induced myocardial injury could be reversed by ALOX5 overexpression. QUE promoted the activity of PI3K/AKT pathway by reducing ALOX5 expression. QUE could alleviate LPS-induced myocardial injury by regulating ALOX5/PI3K/AKT pathway, suggesting that QUE might be used for treating SIC.

Pentacyclic triterpenes, potential novel therapeutic approaches for cardiovascular diseases

Cardiovascular diseases (CVDs) involve dysfunction of the heart and blood vessels and have become major health concerns worldwide. Multiple mechanisms may be involved in the occurrence and development of CVDs. Although therapies for CVDs are constantly being developed and applied, the incidence and mortality of CVDs remain high. The roles of natural compounds in CVD treatment are being explored, providing new approaches for the treatment of CVD. Pentacyclic triterpenes are natural compounds with a basic nucleus of 30 carbon atoms, and they have been widely studied for their potential applications in the treatment of CVDs, to which various pharmacological activities contribute, including anti-inflammatory, antioxidant, and antitumor effects. This review introduces the roles of triterpenoids in the prevention and treatment of CVDs, summarizes their potential underlying mechanisms, and provides a comprehensive overview of the therapeutic potential of triterpenoids in the management of CVDs.

Hederagenin promotes lung cancer cell death by activating CHAC1-dependent ferroptosis pathway

Lung cancer poses a significant threat globally, especially in China. This puts higher demands on the treatment methods and drugs for lung cancer. Natural plants provide valuable resources for the development of anti-cancer drugs. Hederagenin (Hed) is a triterpenoid compound extracted from ivy leaves and has anti-tumor activity against multifarious cancers, including lung cancer. However, the regulatory mechanism of Hed in lung cancer remains unclear. In this study, we used Hed to treat lung cancer cells, and observed the effect of Hed on cell proliferation (including CCK-8 and colony formation experiments), apoptosis (including flow cytometry and apoptosis gene detection (BAX and Bcl-2)). The results showed that Hed induced lung cancer cell death (inhibiting proliferation and promoting apoptosis). Next, we performed bioinformatics analysis of the expression profile GSE186218 and found that Hed treatment significantly increased the expression of CHAC1 gene. CHAC1 is a ferroptosis-inducing gene. RT-qPCR detection of lung cancer clinical tissues and related cell lines also showed that CHAC1 was lowly expressed in lung cancer. Therefore, we knocked down and overexpressed CHAC1 in lung cancer cells, respectively. Subsequently, cell phenotype experiments showed that down-regulating CHAC1 expression inhibited lung cancer cell death (promoting proliferation and inhibiting apoptosis); on the contrary, up-regulating CHAC1 expression promoted lung cancer cell death. To further verify that Hed exerts anti-tumor effects in lung cancer by promoting CHAC1 expression, we performed functional rescue experiments. The results showed that down-regulating CHAC1 expression reversed the promoting effect of Hed on lung cancer cell death. Mechanistically, in vitro and in vivo experiments jointly demonstrated that Hed exerts anti-cancer effects by promoting CHAC1-induced ferroptosis. In summary, our study further enriches the regulatory mechanism of Hed in lung cancer.

An updated review of the pharmacological effects and potential mechanisms of hederagenin and its derivatives

Hederagenin (HG) is a natural pentacyclic triterpenoid that can be isolated from various medicinal herbs. By modifying the structure of HG, multiple derivatives with superior biological activities and safety profiles have been designed and synthesized. Accumulating evidence has demonstrated that HG and its derivatives display multiple pharmacological activities against cancers, inflammatory diseases, infectious diseases, metabolic diseases, fibrotic diseases, cerebrovascular and neurodegenerative diseases, and depression. Previous studies have confirmed that HG and its derivatives combat cancer by exerting cytotoxicity, inhibiting proliferation, inducing apoptosis, modulating autophagy, and reversing chemotherapy resistance in cancer cells, and the action targets involved mainly include STAT3, Aurora B, KIF7, PI3K/AKT, NF-κB, Nrf2/ARE, Drp1, and P-gp. In addition, HG and its derivatives antagonize inflammation through inhibiting the production and release of pro-inflammatory cytokines and inflammatory mediators by regulating inflammation-related pathways and targets, such as NF-κB, MAPK, JAK2/STAT3, Keap1-Nrf2/HO-1, and LncRNA A33/Axin2/β-catenin. Moreover, anti-pathogen, anti-metabolic disorder, anti-fibrosis, neuroprotection, and anti-depression mechanisms of HG and its derivatives have been partially elucidated. The diverse pharmacological properties of HG and its derivatives hold significant implications for future research and development of new drugs derived from HG, which can lead to improved effectiveness and safety profiles.

Emerging regulatory mechanisms in cardiovascular disease: Ferroptosis

Ferroptosis, distinct from apoptosis, necrosis, autophagy, and other types of cell death, is a novel iron-dependent regulated cell death characterized by the accumulation of lipid peroxides and redox imbalance with distinct morphological, biochemical, and genetic features. Dysregulation of iron homeostasis, the disruption of antioxidative stress pathways and lipid peroxidation are crucial in ferroptosis. Ferroptosis is involved in the pathogenesis of several cardiovascular diseases, including atherosclerosis, cardiomyopathy, myocardial infarction, ischemia-reperfusion injury, abdominal aortic aneurysm, aortic dissection, and heart failure. Therefore, a comprehensive understanding of the mechanisms that regulate ferroptosis in cardiovascular diseases will enhance the prevention and treatment of these diseases. This review discusses the latest findings on the molecular mechanisms of ferroptosis and its regulation in cardiovascular diseases, the application of ferroptosis modulators in cardiovascular diseases, and the role of traditional Chinese medicines in ferroptosis regulation to provide a comprehensive understanding of the pathogenesis of cardiovascular diseases and identify new prevention and treatment options.