Tumor-repopulating cells evade ferroptosis via PCK2-dependent phospholipid remodeling.

Whether stem-cell-like cancer cells avert ferroptosis to mediate therapy resistance remains unclear. In this study, using a soft fibrin gel culture system, we found that tumor-repopulating cells (TRCs) with stem-cell-like cancer cell characteristics resist chemotherapy and radiotherapy by decreasing ferroptosis sensitivity. Mechanistically, through quantitative mass spectrometry and lipidomic analysis, we determined that mitochondria metabolic kinase PCK2 phosphorylates and activates ACSL4 to drive ferroptosis-associated phospholipid remodeling. TRCs downregulate the PCK2 expression to confer themselves on a structural ferroptosis-resistant state. Notably, in addition to confirming the role of PCK2-pACSL4(T679) in multiple preclinical models, we discovered that higher PCK2 and pACSL4(T679) levels are correlated with better response to chemotherapy and radiotherapy as well as lower distant metastasis in nasopharyngeal carcinoma cohorts.

Regulation of hepatocyte phospholipid peroxidation signaling by a Chinese patent medicine against psychological stress-induced liver injury.

BACKGROUND: Psychological stress is associated with various diseases including liver dysfunction, yet effective intervention strategies remain lacking due to the unrevealed pathogenesis mechanism. PURPOSE: This study aims to explore the relevance between BMAL1-controlled circadian rhythms and lipoxygenase 15 (ALOX15)-mediated phospholipids peroxidation in psychological stress-induced liver injury, and to investigate whether hepatocyte phospholipid peroxidation signaling is involved in the hepatoprotective effects of a Chinese patent medicine, Pien Tze Huang (PZH). METHODS: Restraint stress models were established to investigate the underlying molecular mechanisms of psychological stress-induced liver injury and the hepatoprotective effects of PZH. Redox lipidomics based on liquid chromatography-tandem mass spectrometry was applied for lipid profiling. RESULTS: The present study discovered that acute restraint stress could induce liver injury. Notably, lipidomic analysis confirmed that phospholipid peroxidation was accumulated in the livers of stressed mice. Additionally, the essential core circadian clock gene Brain and Muscle Arnt-like Protein-1 (Bmal1) was altered in stressed mice. Circadian disruption in mice, as well as BMAL1-overexpression in human HepaRG cells, also appeared to have a significant increase in phospholipid peroxidation, suggesting that stress-induced liver injury is closely related to circadian rhythm and phospholipid peroxidation. Subsequently, arachidonate 15-lipoxygenase (ALOX15), a critical enzyme that contributed to phospholipid peroxidation, was screened as a potential regulatory target of BMAL1. Mechanistically, BMAL1 promoted ALOX15 expression via direct binding to an E-box-like motif in the promoter. Finally, this study revealed that PZH treatment significantly relieved pathological symptoms of psychological stress-induced liver injury with a potential mechanism of alleviating ALOX15-mediated phospholipid peroxidation. CONCLUSION: Our findings illustrate the critical role of BMAL1-triggered phospholipid peroxidation in psychological stress-induced liver injury and provide new insight into treating psychological stress-associated liver diseases by TCM intervention.

Antioxidant and Anti-Inflammatory Properties of Hydrolyzed Royal Jelly Peptide in Human Dermal Fibroblasts: Implications for Skin Health and Care Applications.

Hydrolyzed royal jelly peptide (RJP) has garnered attention for its health-promoting functions. However, the potential applications of RJP in skincare have not been fully explored. In this study, we prepared RJP through the enzymatic hydrolysis of royal jelly protein with trypsin and investigated its antioxidant and anti-inflammatory properties on primary human dermal fibroblasts (HDFs). Our results demonstrate that RJP effectively inhibits oxidative damage induced by H2O2 and lipid peroxidation triggered by AAPH and t-BuOOH in HDFs. This effect may be attributed to the ability of RJP to enhance the level of glutathione and the activities of catalase and glutathione peroxidase 4, as well as its excellent iron chelating capacity. Furthermore, RJP modulates the NLRP3 inflammasome-mediated inflammatory response in HDFs, suppressing the mRNA expressions of NLRP3 and IL-1ß in the primer stage induced by LPS and the release of mature IL-1ß induced by ATP, monosodium urate, or nigericin in the activation stage. RJP also represses the expressions of COX2 and iNOS induced by LPS. Finally, we reveal that RJP exhibits superior antioxidant and anti-inflammatory properties over unhydrolyzed royal jelly protein. These findings suggest that RJP exerts protective effects on skin cells through antioxidative and anti-inflammatory mechanisms, indicating its promise for potential therapeutic avenues for managing oxidative stress and inflammation-related skin disorders.

Characteristics and efficacy of traditional Chinese medicine in the therapeutic strategy of chronic coronary syndrome: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Chronic coronary syndrome (CCS) has always been controversial in its therapeutic strategy. Although invasive treatment and optimal medication therapy (OMT) are the most commonly used treatments, doctors continue to debate the best strategy. However, traditional Chinese medicine (TCM) for CCS is effective clinically. METHODS: To identify potentially eligible observational and experimental studies, we searched Pubmed, the Web of Science, and the China National Knowledge Internet. To be eligible, studies had to report with end-of treatment outcomes, such as major adverse cardiac events (MACE), deaths from myocardial infarctions (MI), all-cause mortality, angina, cardiac mortality, the effectiveness rate of electrocardiographs, and the reduction rate of the Nitroglycerin tablets. Risk differences (RDs) and 95 % confidence intervals (95 % CIs) were calculated based on random-effects models or fixed-effects models. Citation screening, data abstraction, risk assessment, and strength-of-evidence grading were completed by 2 independent reviewers. RESULTS: In Section 1 (13 studies, involving 17,287 patients), showed no significant difference between invasive treatment and medication treatment in MACE (RD = -0.04, 95% CI = -0.08 to 0.00, I2 = 76.4 %), all-cause mortality (RD = -0.01, 95%CI = -0.022 to 0.01, I2 = 73.44 %), MI (RD = 0.00, 95%CI = -0.00 to 0.01, I2 = 0.00 %) and cardiac mortality (RD = 0.00, 95 %CI = -0.01 to 0.01, I2 = 34.9 %). In Section 2 (21 studies, including 1820 patients), compared with WM treatment, TCM + WM treatment increased ECG effectiveness by 18 %, angina effectiveness by 20 %, and stopping or reducing Nitroglycerin tablets by 20 %. In Section 3 (25 studies, including 2859 patients) showed that TCM revealed a better electrocardiogram effective rate (RD = 0.10, 95 %CI = 0.05 to 0.14, I2 = 44.7 %) and angina effective rate (RD = 0.12, 95 %CI = 0.09 to 0.15, I2 = 44.9 %). We identified that TCM treatment properties of "Circulating blood and transforming stasis" and application of warm/heat-properties medicines were frequently used in CCS treatment. CONCLUSIONS: TCM treatment has shown superior beneficial cardioprotective in CCS therapy strategy, among which "Circulating blood and transforming stasis" and the application of warm/heat-properties medicine are its characteristics.

Discovery of a Potent Antiosteoporotic Drug Molecular Scaffold Derived from Angelica sinensis and Its Bioinspired Total Synthesis.

Angelica sinensis, commonly known as Dong Quai in Europe and America and as Dang-gui in China, is a medicinal plant widely utilized for the prevention and treatment of osteoporosis. In this study, we report the discovery of a new category of phthalide from Angelica sinensis, namely falcarinphthalides A and B (1 and 2), which contains two fragments, (3R,8S)-falcarindiol (3) and (Z)-ligustilide (4). Falcarinphthalides A and B (1 and 2) represent two unprecedented carbon skeletons of phthalide in natural products, and their antiosteoporotic activities were evaluated. The structures of 1 and 2, including their absolute configurations, were established using extensive analysis of NMR spectra, chemical derivatization, and ECD/VCD calculations. Based on LC-HR-ESI-MS analysis and DFT calculations, a production mechanism for 1 and 2 involving enzyme-catalyzed Diels-Alder/retro-Diels-Alder reactions was proposed. Falcarinphthalide A (1), the most promising lead compound, exhibits potent in vitro antiosteoporotic activity by inhibiting NF-κB and c-Fos signaling-mediated osteoclastogenesis. Moreover, the bioinspired gram-scale total synthesis of 1, guided by intensive DFT study, has paved the way for further biological investigation. The discovery and gram-scale total synthesis of falcarinphthalide A (1) provide a compelling lead compound and a novel molecular scaffold for treating osteoporosis and other metabolic bone diseases.

Mitigating phospholipid peroxidation of macrophages in stress-induced tumor microenvironment by natural ALOX15/PEBP1 complex inhibitors.

BACKGROUND: The intricate interactions between chronic psychological stress and susceptibility to breast cancer have been recognized, yet the underlying mechanisms remain unexplored. Danzhi Xiaoyao Powder (DZXY), a traditional Chinese medicine (TCM) formula, has found clinical utility in the treatment of breast cancer. Macrophages, as the predominant immune cell population within the tumor microenvironment (TME), play a pivotal role in orchestrating tumor immunosurveillance. Emerging evidence suggests that lipid oxidation accumulation in TME macrophages, plays a critical role in breast cancer development and progression. However, a comprehensive understanding of the pharmacological mechanisms and active components of DZXY related to its clinical application in the treatment of stress-aggravated breast cancer remains elusive. PURPOSE: This study sought to explore the plausible regulatory mechanisms and identify the key active components of DZXY contributing to its therapeutic efficacy in the context of breast cancer. METHODS: Initially, we conducted an investigation into the relationship between the phagocytic capacity of macrophages damaged by psychological stress and phospholipid peroxidation using flow cytometry and LC-MS/MS-based phospholipomics. Subsequently, we evaluated the therapeutic efficacy of DZXY based on the results of the tumor size, tumor weight, the phospholipid peroxidation pathway and phagocytosis of macrophage. Additionally, the target-mediated characterization strategy based on binding of arachidonate 15-lipoxygenase (ALOX15) to phosphatidylethanolamine-binding protein-1 (PEBP1), including molecular docking analysis, microscale thermophoresis (MST) assay, co-immunoprecipitation analysis and activity verification, has been further implemented to reveal the key bio-active components in DZXY. Finally, we evaluated the therapeutic efficacy of isochlorogenic acid C (ICAC) based on the results of tumor size, tumor weight, the phospholipid peroxidation pathway, and macrophage phagocytosis in vivo. RESULTS: The present study demonstrated that phospholipid peroxides, as determined by LC-MS/MS-based phospholipidomics, triggered in macrophages, which in turn compromised their capacity to eliminate tumor cells through phagocytosis. Furthermore, we elucidate the mechanism behind stress-induced PEBP1 to form a complex with ALOX15, thereby mediating membrane phospholipid peroxidation in macrophages. DZXY, demonstrates potent anti-breast cancer therapeutic effects by disrupting the ALOX15/PEBP1 interaction and inhibiting phospholipid peroxidation, ultimately enhancing macrophages' phagocytic capability towards tumor cells. Notably, ICAC emerged as a promising active component in DZXY, which can inhibit the ALOX15/PEBP1 interaction, thereby mitigating phospholipid peroxidation in macrophages. CONCLUSION: Collectively, our findings elucidate stress increases the susceptibility of breast cancer by driving lipid peroxidation of macrophages and suggest the ALOX15/PEBP1 complex as a promising intervention target for DZXY.

Association of glutamate receptor gene polymorphisms with attention-deficit hyperactivity disorder susceptibility: a systematic review and meta-analysis.

Background: There is a growing body of evidence indicating a possible association between genetic variations and attention-deficit hyperactivity disorder (ADHD), although the results have been inconsistent. The objective of this study was to evaluate the correlation between the GRIN2A, GRIN2B and GRM7 gene polymorphisms and ADHD. Methods: A comprehensive meta-analysis and subgroup evaluation was conducted using a fixed-effects model to analyze the association between ADHD and GRIN2B (rs2284411), GRIN2A (rs2229193), and GRM7 (rs3792452) in six genetic models (dominant, recessive, overdominant, homozygous, heterozygous, and allele models). Results: The meta-analysis comprised 8 studies. The overall analysis showed that the GRIN2B rs2284411 T allele and T carries were significantly associated with a decreased risk of ADHD (dominant model:TT + CT vs. CC: OR = 0.783; 95% CI: 0.627-0.980; p = 0.032, allele model:T vs. C: OR = 0.795; 95% CI: 0.656-0.964; p = 0.019), especially in the Korean subgroup (dominant model:TT + CT vs. CC: OR = 0.640; 95% CI: 0.442-0.928; p = 0.019, overdominant model: CT vs. TT + CC: OR = 0.641; 95% CI: 0.438-0.938; p = 0.022, allele model:T vs. C: OR = 0.712; 95% CI: 0.521-0.974; p = 0.034 and heterozygous model: CT vs. CC: OR = 0.630; 95% CI: 0.429-0.925; p = 0.018). However, no meaningful associations were found for rs2229193 and rs3792452. Conclusion: The results of the meta-analysis provide strong evidence that the rs2284411 T allele is significantly associated with reduced susceptibility to ADHD, particularly in the Korean population.

Unveiling the antioxidant superiority of α-tocopherol: Implications for vitamin E nomenclature and classification.

Since the discovery of tocopherols a century ago, α-tocopherol has been distinguished for its unique biological functions. In this study, we aim to elucidate the unique characteristics of α-tocopherol from a chemical perspective. Utilizing density functional theory (DFT) calculations, we evaluated the thermodynamic and kinetic properties of tocopherols, tocotrienols and their oxidation products. Our findings highlight the superior thermodynamic and kinetic properties of α-tocopherol. Although tocopherol substrates generally exhibit similar reactivities, α-tocopherol is distinguished by a larger gap between the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) in intermediates, indicating a potential for greater energy release and favoring reaction progression. Moreover, α-tocopherol shows enhanced efficiency in quenching radical intermediates, especially when combined with vitamin C. All these dates provide valuable support for the naming of vitamin E.

Prenatal hormone stress triggers embryonic cardiac hypertrophy outcome by ubiquitin-dependent degradation of mitochondrial mitofusin 2.

Prenatal stress has been extensively documented as a contributing factor to adverse cardiac development and function in fetuses and infants. The release of glucocorticoids (GCs), identified as a significant stressor, may be a potential factor inducing cardiac hypertrophy. However, the underlying mechanism remains largely unknown. Herein, we discovered that corticosterone (CORT) overload induced cardiac hypertrophy in embryonic chicks and fetal mice in vivo, as well as enlarged cardiomyocytes in vitro. The impaired mitochondria dynamics were observed in CORT-exposed cardiomyocytes, accompanied by dysfunction in oxidative phosphorylation and ATP production. This phenomenon was found to be linked to decreased mitochondrial fusion protein mitofusin 2 (MFN2). Subsequently, we found that CORT facilitated the ubiquitin-proteasome-system-dependent degradation of MFN2 with an enhanced binding of appoptosin to MFN2, serving as the underlying cause. Collectively, our findings provide a comprehensive understanding of the mechanisms by which exposure to stress hormones induces cardiac hypertrophy in fetuses.

Fufang Luohanguo Qingfei granules reduces influenza virus susceptibility via MAVS-dependent type I interferon antiviral signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Fufang Luohanguo Qingfei granules (LQG) is a Chinese patent medicine, clinically used to treat flu-like symptoms including cough with yellow phlegm, impeded phlegm, dry throat and tongue. However, the protective activity of LQG against influenza infection is indeterminate. AIM OF THE STUDY: This study is to investigate the therapeutic effect of LQG on influenza infection and elucidate its underlying mechanism. MATERIALS AND METHODS: In vivo: A viral susceptible mouse model induced by restraint stress was established to investigate LQG's beneficial effects on influenza susceptibility. MAVS knockout (Mavs-/-) mice were used to verify the potential mechanism of LQG. In vitro: Corticosteroid (CORT)-treated A549 cells were employed to identify the active ingredients in LQG. Mice morbidity and mortality were monitored daily for 21 days. Histopathologic changes and inflammatory cytokines in lung tissues were examined by H&E staining and ELISA. RNA-seq was used to explore the signaling pathway influenced by LQG and further confirmed by qPCR. Immunoblotting and immunohistochemistry (IHC) were used to determine the protein levels. CO-IP and DARTS were applied to detect protein-protein interaction and compound-protein interaction, respectively. RESULTS: LQG effectively attenuated the susceptibility of restrained mice to H1N1 infection. LQG significantly boosted the production of IFN-ß transduced by mitochondrial antiviral-signaling protein (MAVS), while MAVS deficiency abrogated its protective effects on restrained mice infected with H1N1. Moreover, in vitro studies further revealed that mogroside Ⅱ B, amygdalin, and luteolin are potentially active components of LQG. CONCLUSION: These results suggested that LQG inhibited the mitofusin 2 (Mfn2)-mediated ubiquitination of MAVS by impeding the E3 ligase synoviolin 1 (SYVN1) recruitment, thereby enhancing IFN-ß antiviral response. Overall, our work elaborates a potential regimen for influenza treatment through reduction of stress-induced susceptibility.

Membrane phospholipid peroxidation promotes loss of dopaminergic neurons in psychological stress-induced Parkinson's disease susceptibility.

Parkinson's disease (PD) is a neurodegenerative disorder associated with α-synuclein aggregation and dopaminergic neuron loss in the midbrain. There is evidence that psychological stress promotes PD progression by enhancing glucocorticoids-related oxidative damage, however, the mechanisms involved are unknown. The present study demonstrated that plasma membrane phospholipid peroxides, as determined by phospholipidomics, triggered ferroptosis in dopaminergic neurons, which in turn contributed to stress exacerbated PD-like motor disorder in mice overexpressing mutant human α-synuclein. Using hormonomics, we identified that stress stimulated corticosteroid release and promoted 15-lipoxygenase-1 (ALOX15)-mediated phospholipid peroxidation. ALOX15 was upregulated by α-synuclein overexpression and acted as a fundamental risk factor in the development of chronic stress-induced parkinsonism and neurodegeneration. Further, we demonstrated the mechanism by which corticosteroids activated the PKC pathway and induced phosphatidylethanolamine-binding protein-1 (PEBP1) to form a complex with ALOX15, thereby facilitating ALOX15 to locate on the plasma membrane phospholipids. A natural product isolated from herbs, leonurine, was screened with activities of inhibiting the ALOX15/PEBP1 interaction and thereby attenuating membrane phospholipid peroxidation. Collectively, our findings demonstrate that stress increases the susceptibility of PD by driving membrane lipid peroxidation of dopaminergic neurons and suggest the ALOX15/PEBP1 complex as a potential intervention target.

LC-MS-Based Redox Phosphoipidomics Analysis in Ferroptosis.

Ferroptosis is a regulated form of cell death characterized by the accumulation of oxidized phospholipids, particularly oxidized phosphatidylethanolamines (PE), which serve as important biomarkers in the progression of various diseases. To facilitate the comprehensive investigation of ferroptosis in biological systems, we present a robust and versatile untargeted redox phospholipidomics method employing normal-phase liquid chromatography-mass spectrometry (LC-MS). This high-throughput technique enables the identification and quantification of dozens of oxidized phospholipid species in a single run, providing valuable insights into the molecular mechanisms underlying ferroptosis. It has been successfully applied to diverse biological samples, including human patients, animals, and cell cultures, and offers a powerful tool for investigating the roles of oxidized phospholipids in the development and progression of various diseases.

A ferroptosis-targeting ceria anchored halloysite as orally drug delivery system for radiation colitis therapy.

Radiation colitis is the leading cause of diarrhea and hematochezia in pelvic radiotherapy patients. This work advances the pathogenesis of radiation colitis from the perspective of ferroptosis. An oral Pickering emulsion is stabilized with halloysite clay nanotubes to alleviate radiation colitis by inhibiting ferroptosis. Ceria nanozyme grown in situ on nanotubes can scavenge reactive oxygen species, and deferiprone was loaded into the lumen of nanotubes to relieve iron stress. These two strategies effectively inhibit lipid peroxidation and rescue ferroptosis in the intestinal microenvironment. The clay nanotubes play a critical role as either a medicine to alleviate colitis, a nanocarrier that targets the inflamed colon by electrostatic adsorption, or an interfacial stabilizer for emulsions. This ferroptosis-based strategy was effective in vitro and in vivo, providing a prospective candidate for radiotherapy protection via rational regulation of specific oxidative stress.

Lycium barbarum (Wolfberry) glycopeptide prevents stress-induced anxiety disorders by regulating oxidative stress and ferroptosis in the medial prefrontal cortex.

BACKGROUND: Lycium barbarum (Wolfberry) extract has been shown to be effective in neuroprotection against aging or neural injury. Knowledge of its potential roles and biological mechanisms in relieving mental disorders, however, remains limited. PURPOSE: To investigate the potency of Lycium barbarum glycopeptide (LbGp) in alleviating anxiety disorders and the related biological mechanisms. METHODS: LbGp was administrated to mice subjected to 14 days of chronic restrain stress (CRS) via the intragastric route. The anxiolytic effect was evaluated by a battery of behavioral assays. The morphology of neurons and glial cells was evaluated, and cortical neuronal calcium transients were recorded in vivo. The molecular mechanism of LbGp was also investigated. RESULTS: LbGp effectively relieved anxiety-like and depressive behaviors under CRS. Mechanistic studies further showed that LbGp treatment relieved oxidative stress and lipid peroxidation in the medial prefrontal cortex (mPFC). In particular, the ferroptosis pathway was inhibited by LbGp, revealing a previously unrecognized mechanism of the anxiolytic role of wolfberry extract. CONCLUSION: In summary, our results supported the future development of LbGp to prevent or ameliorate stress-induced anxiety disorders. Our work provides a promising strategy for early intervention for pateitents with mental disorders by applying natural plant extracts.

Midbrain dopamine oxidation links ubiquitination of glutathione peroxidase 4 to ferroptosis of dopaminergic neurons.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by the gradual loss of midbrain dopaminergic neurons in association with aggregation of α-synuclein. Oxidative damage has been widely implicated in this disease, though the mechanisms involved remain elusive. Here, we demonstrated that preferential accumulation of peroxidized phospholipids and loss of the antioxidant enzyme glutathione peroxidase 4 (GPX4) were responsible for vulnerability of midbrain dopaminergic neurons and progressive motor dysfunctions in a mouse model of PD. We also established a mechanism wherein iron-induced dopamine oxidation modified GPX4, thereby rendering it amenable to degradation via the ubiquitin-proteasome pathway. In conclusion, this study unraveled what we believe to be a novel pathway for dopaminergic neuron degeneration during PD pathogenesis, driven by dopamine-induced loss of antioxidant GPX4 activity.

Reducing lipid peroxidation attenuates stress-induced susceptibility to herpes simplex virus type 1.

Psychological stress increases the susceptibility to herpes simplex virus type 1 (HSV-1) infection. There is no effective intervention due to the unknown pathogenesis mechanisms. In this study we explored the molecular mechanisms underlying stress-induced HSV-1 susceptibility and the antiviral effect of a natural compound rosmarinic acid (RA) in vivo and in vitro. Mice were administered RA (11.7, 23.4 mg·kg-1·d-1, i.g.) or acyclovir (ACV, 206 mg·kg-1·d-1, i.g.) for 23 days. The mice were subjected to restraint stress for 7 days followed by intranasal infection with HSV-1 on D7. At the end of RA or ACV treatment, mouse plasma samples and brain tissues were collected for analysis. We showed that both RA and ACV treatment significantly decreased stress-augmented mortality and alleviated eye swelling and neurological symptoms in HSV-1-infected mice. In SH-SY5Y cells and PC12 cells exposed to the stress hormone corticosterone (CORT) plus HSV-1, RA (100 µM) significantly increased the cell viability, and inhibited CORT-induced elevation in the expression of viral proteins and genes. We demonstrated that CORT (50 µM) triggered lipoxygenase 15 (ALOX15)-mediated redox imbalance in the neuronal cells, increasing the level of 4-HNE-conjugated STING, which impaired STING translocation from the endoplasmic reticulum to Golgi; the abnormality of STING-mediated innate immunity led to HSV-1 susceptibility. We revealed that RA was an inhibitor of lipid peroxidation by directly targeting ALOX15, thus RA could rescue stress-weakened neuronal innate immune response, thereby reducing HSV-1 susceptibility in vivo and in vitro. This study illustrates the critical role of lipid peroxidation in stress-induced HSV-1 susceptibility and reveals the potential for developing RA as an effective intervention in anti-HSV-1 therapy.

ALOX5 inhibition protects against dopaminergic neurons undergoing ferroptosis.

Oxidative disruption of dopaminergic neurons is regarded as a crucial pathogenesis in Parkinson's disease (PD), eventually causing neurodegenerative progression. (-)-Clausenamide (Clau) is an alkaloid isolated from plant Clausena lansium (Lour.), which is well-known as a scavenger of lipid peroxide products and exhibiting neuroprotective activities both in vivo and in vitro, yet with the in-depth molecular mechanism unrevealed. In this study, we evaluated the protective effects and mechanisms of Clau on dopaminergic neuron. Our results showed that Clau directly interacted with the Ser663 of ALOX5, the PKCα-phosphorylation site, and thus prevented the nuclear translocation of ALOX5, which was essential for catalyzing the production of toxic lipids 5-HETE. LC-MS/MS-based phospholipidomics analysis demonstrated that the oxidized membrane lipids were involved in triggering ferroptotic death in dopaminergic neurons. Furthermore, the inhibition of ALOX5 was found to significantly improving behavioral defects in PD mouse model, which was confirmed associated with the effects of attenuating the accumulation of lipid peroxides and neuronal damages. Collectively, our findings provide an attractive strategy for PD therapy by targeting ALOX5 and preventing ferroptosis in dopaminergic neurons.

Regulation of phospholipid peroxidation signaling by a traditional Chinese medicine formula for coronary heart disease.

BACKGROUND: Phospholipid peroxidation signaling was recently revealed as a novel pathological mechanism of coronary heart disease (CHD), and small molecules involved in this redox-metabolic pathway are suggested as the potential anti-CHD drugs. Danlou Tablet (DLT), a famous traditional Chinese medicine (TCM) formula characterized by multi-component and multi-target regulation, is widely used in the clinical treatment of CHD by regulating lipid metabolism. However, little information is available addressing the corresponding pharmacological mechanisms and associated active components of DLT. PURPOSE: To study whether phospholipid peroxidation involves a novel mechanism of DLT for the therapeutic effect of CHD and to explain the essential active components. METHODS: Firstly, the HPLC fingerprint was constructed to ensure the controllability of the quality of DLT. Then, a CHD animal model with the characteristics of lipid disorder and myocardial ischemia was established by a high-fat diet (HFD) combined with left anterior descending coronary artery (LAD) ligation. The therapeutic effect of DLT was further evaluated based on the results of the rat survival rate, cardiac function, cardiac histopathology, and myocardial ischemia indicators. Correspondingly, whether DLT can regulate the key indicators (ALOX15, GPX4, MDA, GSH, and NADPH) of the phospholipid peroxidation pathway was investigated, and Alox15-/- mice have been applied to confirm the mechanism of DLT. Finally, the target-mediated characterization strategy based on ALOX15, including the integration of in vivo component characterization, network pharmacology, molecular docking analysis, and activity verification, has been further implemented to reveal the key bio-active components in DLT. RESULTS: In this study, a high-fat diet (HFD) combined with left anterior descending coronary artery (LAD) ligation was utilized to generate a CHD model, and DLT significantly improved the cardiac dysfunction and reduced the myocardial cell death susceptibility. Further results revealed that DLT reversed the protein expression of ALOX15 and GPX4, the key proteins of phospholipid peroxidation pathways, which subsequently influenced the parameters of phospholipid peroxidation (MDA, GSH, and NADPH). The ALOX15 knockout transgenic animal model confirmed that Alox15-/- mice lost their cardioprotective effects with DLT, suggesting that DLT exerted therapeutic effects on CHD by regulating ALOX15-mediated phospholipid peroxidation. Finally, the target-mediated characterization strategy identified that daidzein is an active component in DLT against CHD by modulating ALOX15. CONCLUSION: Innovatively, ALOX15-mediated phospholipid peroxidation was identified as one of the critical mechanisms of DLT exerting cardioprotective effects. Our findings elucidate a novel mechanism of DLT and provide some new drug evaluation targets and therapeutic strategies for CHD.