Arsenic trioxide induces macrophage autophagy and atheroprotection by regulating ROS-dependent TFEB nuclear translocation and AKT/mTOR pathway

Melatonin Attenuates Arsenic-Induced Neurotoxicity in Rats Through the Regulation of miR-34a/miR-144 in Sirt1/Nrf2 Pathway

Arsenic (As) exposure is known to cause several neurological disorders through various molecular mechanisms such as oxidative stress, apoptosis, and autophagy. In the current study, we assessed the effect of melatonin (Mel) on As-induced neurotoxicity. Thirty male Wistar rat were treated daily for 28 consecutive days. As (15 mg/kg, gavage) and Mel (10 and 20 mg/kg, i.p.) were administered to rats. Morris water maze test was done to evaluate learning and memory impairment in training days and probe trial. Oxidative stress markers including MDA and GSH levels, SOD activity, and HO-1 levels were measured. Besides, the levels of apoptosis (caspase 3, Bax/Bcl2 ratio) and autophagy markers (Sirt1, Beclin-1, and LC3 II/I ratio) as well as the expression of miR-144 and miR-34a in cortex tissue were determined. As exposure disturbed learning and memory in animals and Mel alleviated these effects. Also, Mel recovered cortex pathological damages and oxidative stress induced by As. Furthermore, As increased the levels of apoptosis and autophagy proteins in cortex, while Mel (20 mg/kg) decreased apoptosis and autophagy. Also, Mel increased the expression of miR-144 and miR-34a which inhibited by As. In conclusion, Mel administration attenuated As-induced neurotoxicity through anti-oxidative, anti-apoptotic, and anti-autophagy mechanisms, which may be recommended as a therapeutic target for neurological disorders.

Hesperidin Alleviates Hepatic Injury Caused by Deoxynivalenol Exposure through Activation of mTOR and AKT/GSK3β/TFEB Pathways

Deoxynivalenol (DON) is a common agricultural mycotoxin that is chemically stable and not easily removed from cereal foods. When organisms consume food made from contaminated crops, it can be hazardous to their health. Numerous studies in recent years have found that hesperidin (HDN) has hepatoprotective effects on a wide range of toxins. However, few scholars have explored the potential of HDN in attenuating DON-induced liver injury. In this study, we established a low-dose DON exposure model and intervened with three doses of HDN, acting on male C57 BL/6 mice and AML12 cells, which served as in vivo and in vitro models, respectively, to investigate the protective mechanism of HDN against DON exposure-induced liver injury. The results suggested that DON disrupted hepatic autophagic fluxes, thereby impairing liver structure and function, and HDN significantly attenuated these changes. Further studies revealed that HDN alleviated DON-induced excessive autophagy through the mTOR pathway and DON-induced lysosomal dysfunction through the AKT/GSK3β/TFEB pathway. Overall, our study suggested that HDN could ameliorate DON-induced autophagy flux disorders via the mTOR pathway and the AKT/GSK3β/TFEB pathway, thereby reducing liver injury.

Mitophagy in relation to chronic inflammation/ROS in aging

Various assaults on mitochondria occur during the human aging process, contributing to mitochondrial dysfunction. This mitochondrial dysfunction is intricately connected with aging and diseases associated with it. In vivo, the accumulation of defective mitochondria can precipitate inflammatory and oxidative stress, thereby accelerating aging. Mitophagy, an essential selective autophagy process, plays a crucial role in managing mitochondrial quality control and homeostasis. It is a highly specialized mechanism that systematically removes damaged or impaired mitochondria from cells, ensuring their optimal functioning and survival. By engaging in mitophagy, cells are able to maintain a balanced and stable environment, free from the potentially harmful effects of dysfunctional mitochondria. An ever-growing body of research highlights the significance of mitophagy in both aging and age-related diseases. Nonetheless, the association between mitophagy and inflammation or oxidative stress induced by mitochondrial dysfunction remains ambiguous. We review the fundamental mechanisms of mitophagy in this paper, delve into its relationship with age-related stress, and propose suggestions for future research directions.

Transcription factor EB-mediated autophagy affects cell migration and inhibits apoptosis to promote endometriosis

Autophagy has emerged as an important process of cell metabolism. With continuous in-depth research on autophagy, TFEB has been a key transcription factor regulating autophagy levels in recent years. Studies have established that TFEB regulates autophagy and apoptosis in various diseases. However, the relationship between TFEB and the pathogenesis of endometriosis remains unclear. This study aimed to investigate the effect of TFEB on the mechanism of endometriosis progression. The results showed that TFEB and autophagy-related protein LC3 are highly expressed in ectopic endometrium of patients with endometriosis, overexpression of TFEB in cultured human endometrial stromal cells (HESCs) by lentivirus not only promoted autophagy but also inhibited apoptosis. In addition, the migration and invasion ability of HESCs were enhanced by TFEB overexpression. Furthermore, inhibiting autophagy with specific inhibitors can attenuate migration and invasion of HESCs induced by TFEB. The rat models of endometriosis show that TFEB knockdown can suppress lesion growth in vivo. Our results suggest that autophagy may be involved in the progression mechanism of endometriosis, and the mechanism of autophagy disorder in endometriosis is probably related to TFEB. TFEB may be a key molecule in promoting endometriosis.

Matrine induces autophagic cell death by triggering ROS/AMPK/mTOR axis and apoptosis in multiple myeloma

Despite significant advancements in multiple myeloma (MM) treatment in recent years, most patients will eventually develop resistance or experience relapse. Matrine, a primary active compound of traditional Chinese medicinal herb Sophora flavescens Ait, has been found to have anti-tumor properties in various types of malignant tumors. Whether autophagy plays a crucial role in the anti-MM effect of matrine remain unknown. Herein, we found that matrine could trigger apoptosis and cell cycle arrest, and meanwhile induce autophagy in MM cells in vitro. We further ascertained the role of autophagy by using ATG5 siRNA or the autophagy inhibitor spautin-1, which partially reversed matrine's inhibitory effect on MM cells. Conversely, the combination of matrine with the autophagy inducer rapamycin enhanced their anti-tumor activity. These findings suggest that autophagy induced by matrine can lead to cell death in MM cells. Further mechanism investigation revealed that matrine treatment increased the levels of reactive oxygen species (ROS) and AMPKα1 phosphorylation and decreased the phosphorylation of mTOR in MM cells. Additionally, co-treatment with AMPKα1 siRNA or the ROS scavenger N-acetyl-1-cysteine weakened the increase in autophagy that was induced by matrine. Finally, we demonstrated a synergistic inhibitory effect of matrine and rapamycin against MM in a xenograft mouse model. Collectively, our findings provided novel insights into the anti-MM efficacy of matrine and suggest that matrine induces autophagy by triggering ROS/AMPK/mTOR axis in MM cells, and combinatorial treatment of matrine and rapamycin may be a promising therapeutic strategy against MM.

A potential early-atheroprotective target: Irgm1 mediates lymphangiogenesis through LEC autophagy by Tfeb translocation

Lymphatic dysfunction is a pivotal pathological mechanism underlying the development of early atherosclerotic plaques. Potential targets of lymphatic function must be identified to realize the early prevention and treatment of atherosclerosis (AS). The immunity-related GTPase Irgm1 is involved in orchestrating cellular autophagy and apoptosis. However, the effect of Irgm1 on early AS progression, particularly through alterations in lymphatic function, remains unclear. In this study, we confirmed the protective effect of lymphangiogenesis on early-AS in vivo. Subsequently, an in vivo model of early AS mice with Irgm1 knockdown shows that Irgm1 reduces early atherosclerotic plaque burden by promoting lymphangiogenesis. Given that lymphatic endothelial cell (LEC) autophagy significantly contributes to lymphangiogenesis, Irgm1 may enhance lymphatic circulation by promoting LEC autophagy. Moreover, Irgm1 orchestrates autophagy in LECs by inhibiting mTOR and facilitating nuclear translocation of Tfeb. Collectively, these processes lead to lymphangiogenesis. Thus, this study establishes a link between Irgm1 and early AS, thus revealing a novel mechanism by which Irgm1 exerts an early protective influence on AS within the context of lymphatic circulation. The insights gained from this study have the potential to revolutionize the approach and management of AS onset.

Sodium arsenite and arsenic trioxide differently affect the oxidative stress of lymphoblastoid cells: An intricate crosstalk between mitochondria, autophagy and cell death

Although the toxicity of arsenic depends on its chemical forms, few studies have taken into account the ambiguous phenomenon that sodium arsenite (NaAsO2) acts as a potent carcinogen while arsenic trioxide (ATO, As2O3) serves as an effective therapeutic agent in lymphoma, suggesting that NaAsO2 and As2O3 may act via paradoxical ways to either promote or inhibit cancer pathogenesis. Here, we compared the cellular response of the two arsenical compounds, NaAsO2 and As2O3, on the Burkitt lymphoma cell model, the Epstein Barr Virus (EBV)-positive P3HR1 cells. Using flow cytometry and biochemistry analyses, we showed that a NaAsO2 treatment induces P3HR1 cell death, combined with drastic drops in ΔΨm, NAD(P)H and ATP levels. In contrast, As2O3-treated cells resist to cell death, with a moderate reduction of ΔΨm, NAD(P)H and ATP. While both compounds block cells in G2/M and affect their protein carbonylation and lipid peroxidation, As2O3 induces a milder increase in superoxide anions and H2O2 than NaAsO2, associated to a milder inhibition of antioxidant defenses. By electron microscopy, RT-qPCR and image cytometry analyses, we showed that As2O3-treated cells display an overall autophagic response, combined with mitophagy and an unfolded protein response, characteristics that were not observed following a NaAsO2 treatment. As previous works showed that As2O3 reactivates EBV in P3HR1 cells, we treated the EBV- Ramos-1 cells and showed that autophagy was not induced in these EBV- cells upon As2O3 treatment suggesting that the boost of autophagy observed in As2O3-treated P3HR1 cells could be due to the presence of EBV in these cells. Overall, our results suggest that As2O3 is an autophagic inducer which action is enhanced when EBV is present in the cells, in contrast to NaAsO2, which induces cell death. That's why As2O3 is combined with other chemicals, as all-trans retinoic acid, to better target cancer cells in therapeutic treatments.

PCSK9 induces endothelial cell autophagy by regulating the PI3K/ATK pathway in atherosclerotic coronary heart disease

OBJECTIVE

Atherosclerosis is a chronic inflammatory disease of the arteries, and its pathogenesis is related to endothelial dysfunction. It has been found that the protein convertase subtilin/kexin9 type (PCSK9) plays an important role in AS, but its specific mechanism is still unclear.

METHODS

In this study, we first cultured human umbilical vein endothelial cells (HUVECs) with 50 or 100μg/ml oxidized low-density lipoprotein (ox-LDL) for 24 hours to establish a coronary atherosclerosis cell model.

RESULTS

The results showed that ox-LDL induced HUVEC injury and autophagy and upregulated PCSK9 protein expression in HUVECs in a concentration-dependent manner. Silencing PCSK9 expression with siRNA inhibited ox-LDL-induced HUVEC endothelial dysfunction, inhibited the release of inflammatory factors, promoted HUVEC proliferation and inhibited apoptosis. In addition, ox-LDL increased the expression of LC3B-I and LC3B-II and decreased the expression of p62. However, these processes are reversed by sh-PCSK9. In addition, sh-PCSK9 can inhibit PI3K, AKT and mTOR phosphorylation and promote autophagy.

CONCLUSION

Taken together, our research shows that silencing PCSK9 inhibits the PI3K/ATK/mTOR pathway to activate ox-LDL-induced autophagy in vascular endothelial cells, alleviating endothelial cell injury and inflammation.

Cathelicidin LL-37 promotes wound healing in diabetic mice by regulating TFEB-dependent autophagy

Diabetic patients often experience impaired wound healing. Human cathelicidin LL-37 possesses various biological functions, such as anti-microbial, anti-inflammatory, and pro-wound healing activities. Autophagy has important effects on skin wound healing. However, little is known about whether LL-37 accelerates diabetic wound healing by regulating autophagy. In the study, we aimed to investigate the role of autophagy in LL-37-induced wound healing and uncover the underlying mechanisms involved. A full-thickness wound closure model was established in diabetic mice to evaluate the effects of LL-37 and an autophagy inhibitor (3-MA) on wound healing. The roles of LL-37 and 3-MA in regulating keratinocyte migration were assessed using transwell migration and wound healing assays. The activation of transcription factor EB (TFEB) was measured using western blotting and immunofluorescence (IF) assays of its nuclear translocation. The results showed that LL-37 treatment improved wound healing in diabetic mice, whereas these effects were reversed by 3-MA. In vitro, 3-MA decreased the effects of LL-37 on promoting HaCat keratinocyte migration in the presence of high glucose (HG). Mechanistically, LL-37 promoted TFEB activation and resulted in subsequent activation of autophagy, as evidenced by increased nuclear translocation of TFEB and increased expression of ATG5, ATG7, and beclin 1 (BECN1), whereas these changes were blocked by TFEB knockdown. As expected, TFEB knockdown damaged the effects of LL-37 on promoting keratinocyte migration. Collectively, these results suggest that LL-37 accelerates wound healing in diabetic mice by activating TFEB-dependent autophagy, providing new insights into the mechanism by which LL-37 promotes diabetic wound healing.

Autophagy in Its (Proper) Context: Molecular Basis, Biological Relevance, Pharmacological Modulation, and Lifestyle Medicine

Autophagy plays a critical role in maintaining cellular homeostasis and responding to various stress conditions by the degradation of intracellular components. In this narrative review, we provide a comprehensive overview of autophagy's cellular and molecular basis, biological significance, pharmacological modulation, and its relevance in lifestyle medicine. We delve into the intricate molecular mechanisms that govern autophagy, including macroautophagy, microautophagy and chaperone-mediated autophagy. Moreover, we highlight the biological significance of autophagy in aging, immunity, metabolism, apoptosis, tissue differentiation and systemic diseases, such as neurodegenerative or cardiovascular diseases and cancer. We also discuss the latest advancements in pharmacological modulation of autophagy and their potential implications in clinical settings. Finally, we explore the intimate connection between lifestyle factors and autophagy, emphasizing how nutrition, exercise, sleep patterns and environmental factors can significantly impact the autophagic process. The integration of lifestyle medicine into autophagy research opens new avenues for promoting health and longevity through personalized interventions.

Endoplasmic reticulum stress-related gene expression causes the progression of dilated cardiomyopathy by inducing apoptosis

Background: Previous studies have shown that endoplasmic reticulum stress (ERS) -induced apoptosis is involved in the pathogenesis of dilated cardiomyopathy (DCM). However, the molecular mechanism involved has not been fully characterized. Results: In total, eight genes were obtained at the intersection of 1,068 differentially expressed genes (DEGs) from differential expression analysis between DCM and healthy control (HC) samples, 320 module genes from weighted gene co-expression network analysis (WGCNA), and 2,009 endoplasmic reticulum stress (ERGs). These eight genes were found to be associated with immunity and angiogenesis. Four of these genes were related to apoptosis. The upregulation of MX1 may represent an autocompensatory response to DCM caused by a virus that inhibits viral RNA and DNA synthesis, while acting as an autoimmune antigen and inducing apoptosis. The upregulation of TESPA1 would lead to the dysfunction of calcium release from the endoplasmic reticulum. The upregulation of THBS4 would affect macrophage differentiation and apoptosis, consistent with inflammation and fibrosis of cardiomyocytes in DCM. The downregulation of MYH6 would lead to dysfunction of the sarcomere, further explaining cardiac remodeling in DCM. Moreover, the expression of genes affecting the immune micro-environment was significantly altered, including TGF-β family member. Analysis of the co-expression and competitive endogenous RNA (ceRNA) network identified XIST, which competitively binds seven target microRNAs (miRNAs) and regulates MX1 and THBS4 expression. Finally, bisphenol A and valproic acid were found to target MX1, MYH6, and THBS4. Conclusion: We have identified four ERS-related genes (MX1, MYH6, TESPA1, and THBS4) that are dysregulated in DCM and related to apoptosis. This finding should help deepen understanding of the role of endoplasmic reticulum stress-induced apoptosis in the development of DCM.

Macrophage polarization: an important role in inflammatory diseases

Macrophages are crucial cells in the human body's innate immunity and are engaged in a variety of non-inflammatory reactions. Macrophages can develop into two kinds when stimulated by distinct internal environments: pro-inflammatory M1-like macrophages and anti-inflammatory M2-type macrophages. During inflammation, the two kinds of macrophages are activated alternatively, and maintaining a reasonably steady ratio is critical for maintaining homeostasis in vivo. M1 macrophages can induce inflammation, but M2 macrophages suppress it. The imbalance between the two kinds of macrophages will have a significant impact on the illness process. As a result, there are an increasing number of research being conducted on relieving or curing illnesses by altering the amount of macrophages. This review summarizes the role of macrophage polarization in various inflammatory diseases, including autoimmune diseases (RA, EAE, MS, AIH, IBD, CD), allergic diseases (allergic rhinitis, allergic dermatitis, allergic asthma), atherosclerosis, obesity and type 2 diabetes, metabolic homeostasis, and the compounds or drugs that have been discovered or applied to the treatment of these diseases by targeting macrophage polarization.

Crosstalk between m6A modification and autophagy in cancer

Autophagy is a cellular self-degradation process that plays a crucial role in maintaining metabolic functions in cells and organisms. Dysfunctional autophagy has been linked to various diseases, including cancer. In cancer, dysregulated autophagy is closely associated with the development of cancer and drug resistance, and it can have both oncogenic and oncostatic effects. Research evidence supports the connection between m6A modification and human diseases, particularly cancer. Abnormalities in m6A modification are involved in the initiation and progression of cancer by regulating the expression of oncogenes and oncostatic genes. There is an interaction between m6A modification and autophagy, both of which play significant roles in cancer. However, the molecular mechanisms underlying this relationship are still unclear. m6A modification can either directly inhibit autophagy or promote its initiation, but the complex relationship between m6A modification, autophagy, and cancer remains poorly understood. Therefore, this paper aims to review the dual role of m6A and autophagy in cancer, explore the impact of m6A modification on autophagy regulation, and discuss the crucial role of the m6A modification-autophagy axis in cancer progression and treatment resistance.

Chronic arsenic exposure suppresses proteasomal and autophagic protein degradation

Ubiquitin Proteasomal System (UPS) and autophagy dysregulation initiate cancer. These pathways are regulated by zinc finger proteins. Trivalent inorganic arsenic (iAs) displaces zinc from zinc finger proteins disrupting functions of important cellular proteins. The effect of chronic environmental iAs exposure (100 nM) on UPS has not been studied. We tested the hypothesis that environmental iAs exposure suppresses UPS, activating autophagy as a compensatory mechanism. We exposed skin (HaCaT and Ker-CT; independent quadruplicates) and lung (BEAS-2B; independent triplicates) cell cultures to 0 or 100 nM iAs for 7 or 8 weeks. We quantified ER stress (XBP1 splicing employing Reverse Transcriptase -Polymerase Chain Reaction), proteasomal degradation (immunoblots), and initiation and completion of autophagy (immunoblots). We demonstrate that chronic iAs exposure suppresses UPS, initiates autophagy, but suppresses autophagic protein degradation in skin and lung cell lines. Our data suggest that chronic iAs exposure inhibits autophagy which subsequently suppresses UPS.

SLAMF7 Promotes Foam Cell Formation of Macrophage by Suppressing NR4A1 Expression During Carotid Atherosclerosis

Macrophage-derived lipid-laden foam cells from the subendothelium play a crucial role in the initiation and progression of atherosclerosis. However, the molecule mechanism that regulates the formation of foam cells is not completely understood. Here, we found that SLAMF7 was upregulated in mice bone marrow-derived macrophages and RAW264.7 cells stimulated with oxidized low-density lipoprotein (ox-LDL). SLAMF7 promoted ox-LDL-mediated macrophage lipid accumulation and M1-type polarization. SLAMF7 deficiency reduced serum lipid levels and improved the lesions area of carotid plaque and aortic arch in high-fat diet-fed ApoE-/- mice. In response to ox-LDL, SLAMF7 downregulated NR4A1 and upregulated RUNX3 through transcriptome sequencing analysis. Overexpression NR4A1 reversed SLAMF7-induced lipid uptake and M1 polarization via inhibiting RUNX3 expression. Furthermore, RUNX3 enhanced foam cell formation and M1-type polarization. Taken together, the study suggested that SLAMF7 play contributing roles in the pro-atherogenic effects by regulating NR4A1-RUNX3.

Marine-Fungus-Derived Natural Compound 4-Hydroxyphenylacetic Acid Induces Autophagy to Exert Antithrombotic Effects in Zebrafish

Marine natural products are important sources of novel drugs. In this study, we isolated 4-hydroxyphenylacetic acid (HPA) from the marine-derived fungus Emericellopsis maritima Y39-2. The antithrombotic activity and mechanism of HPA were reported for the first time. Using a zebrafish model, we found that HPA had a strong antithrombotic activity because it can significantly increase cardiac erythrocytes, blood flow velocity, and heart rate, reduce caudal thrombus, and reverse the inflammatory response caused by Arachidonic Acid (AA). Further transcriptome analysis and qRT-PCR validation demonstrated that HPA may regulate autophagy by inhibiting the PI3K/AKT/mTOR signaling pathway to exert antithrombotic effects.

Roseburia intestinalis sensitizes colorectal cancer to radiotherapy through the butyrate/OR51E1/RALB axis

The radioresistant signature of colorectal cancer (CRC) hampers the clinical utility of radiotherapy. Here, we find that fecal microbiota transplantation (FMT) potentiates the tumoricidal effects of radiation and degrades the intertwined adverse events in azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced CRC mice. FMT cumulates Roseburia intestinalis (R. intestinalis) in the gastrointestinal tract. Oral gavage of R. intestinalis assembles at the CRC site and synthetizes butyrate, sensitizing CRC to radiation and alleviating intestinal toxicity in primary and CRC hepatic metastasis mouse models. R. intestinalis-derived butyrate activates OR51E1, a G-protein-coupled receptor overexpressing in patients with rectal cancer, facilitating radiogenic autophagy in CRC cells. OR51E1 shows a positive correlation with RALB in clinical rectal cancer tissues and CRC mouse model. Blockage of OR51E1/RALB signaling restrains butyrate-elicited autophagy in irradiated CRC cells. Our findings highlight that the gut commensal bacteria R. intestinalis motivates radiation-induced autophagy to accelerate CRC cell death through the butyrate/OR51E1/RALB axis and provide a promising radiosensitizer for CRC in a pre-clinical setting.

Targeting autophagy drug discovery: Targets, indications and development trends

Autophagy plays a vital role in sustaining cellular homeostasis and its alterations have been implicated in the etiology of many diseases. Drugs development targeting autophagy began decades ago and hundreds of agents were developed, some of which are licensed for the clinical usage. However, no existing intervention specifically aimed at modulating autophagy is available. The obstacles that prevent drug developments come from the complexity of the actual impact of autophagy regulators in disease scenarios. With the development and application of new technologies, several promising categories of compounds for autophagy-based therapy have emerged in recent years. In this paper, the autophagy-targeted drugs based on their targets at various hierarchical sites of the autophagic signaling network, e.g., the upstream and downstream of the autophagosome and the autophagic components with enzyme activities are reviewed and analyzed respectively, with special attention paid to those at preclinical or clinical trials. The drugs tailored to specific autophagy alone and combination with drugs/adjuvant therapies widely used in clinical for various diseases treatments are also emphasized. The emerging drug design and development targeting selective autophagy receptors (SARs) and their related proteins, which would be expected to arrest or reverse the progression of disease in various cancers, inflammation, neurodegeneration, and metabolic disorders, are critically reviewed. And the challenges and perspective in clinically developing autophagy-targeted drugs and possible combinations with other medicine are considered in the review.

LncRNA XXYLT1-AS2 promotes tumor progression via autophagy inhibition through ubiquitinated degradation of TFEB in hepatocellular carcinoma

PURPOSE

There is compelling evidence that long-stranded non-coding RNAs (lncRNAs) play an important role in the progression of hepatocellular carcinoma (HCC). The aim of this study was to investigate the role of lncRNA XXYLT1 antisense-2 (XXYLT1-AS2) in HCC progression.

METHODS

Real-time PCR was used to assess the levels of XXYLT1-AS2 in plasma from HCC and normal patients. Cell proliferation, apoptosis, migration, and invasion were monitored, and tumor xenografts were established to investigate the biological functions of XXYLT1-AS2 by gain-of-function and loss-of-function studies in vitro and in vivo, the expression of autophagy biomarkers and transcriptional factor EB (TFEB) was examined by immunoprecipitation, ubiquitination assays, and western blotting. Autophagy inhibitor, 3-methyladenine (3MA), and proteasome inhibitor, MG132, were used to verify the role of autophagy in HCC progression and the effect of XXYLT1-AS2 on TFEB ubiquitination, respectively.

RESULTS

In this study, we identified that lncRNA XXYLT1-AS2 is highly expressed in HCC plasma and promotes tumor growth in vivo. In functional studies, it was found that silent expression of XXYLT1-AS2 inhibited HCC proliferation, migration, invasion, and activated autophagy of HCC cells, which were attenuated by autophagy inhibitor, 3MA. Mechanistically, XXYLT1-AS2 decreased the protein level of TFEB through promoting its degradation by ubiquitin proteasome pathway.

CONCLUSION

XXYLT1-AS2 plays an oncogenic role in HCC progression through inhibition of autophagy via promoting the degradation of TFEB, and thus could be a novel target for HCC treatment.

Arsenic trioxide: applications, mechanisms of action, toxicity and rescue strategies to date

Arsenical medicine has obtained its status in traditional Chinese medicine for more than 2,000 years. In the 1970s, arsenic trioxide was identified to have high efficacy and potency for the treatment of acute promyelocytic leukemia, which promoted many studies on the therapeutic effects of arsenic trioxide. Currently, arsenic trioxide is widely used to treat acute promyelocytic leukemia and various solid tumors through various mechanisms of action in clinical practice; however, it is accompanied by a series of adverse reactions, especially cardiac toxicity. This review presents a comprehensive overview of arsenic trioxide from preclinical and clinical efficacy, potential mechanisms of action, toxicities, and rescue strategies for toxicities to provide guidance or assistance for the clinical application of arsenic trioxide.

Effect of reactive oxygen, nitrogen, and sulfur species on signaling pathways in atherosclerosis

Atherosclerosis is a chronic inflammatory disease in which fats, lipids, cholesterol, calcium, proliferating smooth muscle cells, and immune cells accumulate in the intima of the large arteries, forming atherosclerotic plaques. A complex interplay of various vascular and immune cells takes place during the initiation and progression of atherosclerosis. Multiple reports indicate that tight control of reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive sulfur species (RSS) production is critical for maintaining vascular health. Unrestricted ROS and RNS generation may lead to activation of various inflammatory signaling pathways, facilitating atherosclerosis. Given these deleterious consequences, it is important to understand how ROS and RNS affect the signaling processes involved in atherogenesis. Conversely, RSS appears to exhibit an atheroprotective potential and can alleviate the deleterious effects of ROS and RNS. Herein, we review the literature describing the effects of ROS, RNS, and RSS on vascular smooth muscle cells, endothelial cells, and macrophages and focus on how changes in their production affect the initiation and progression of atherosclerosis. This review also discusses the contribution of ROS, RNS, and RSS in mediating various post-translational modifications, such as oxidation, nitrosylation, and sulfation, of the molecules involved in inflammatory signaling.

Mebendazole induces apoptosis and inhibits migration via the reactive oxygen species-mediated STAT3 signaling downregulation in non-small cell lung cancer

Background

The incidence and mortality of non-small cell lung cancer (NSCLC) are extremely high. Previous research has confirmed that the signal transducer and activator of the transcription 3 (STAT3) protein critically participate in the tumorigenesis of NSCLC. Mebendazole (MBZ) has exerts a larger number of pharmacological activities and has anticancer effects in lung cancer, but its mechanism of action remains unclear. This study thus aimed to clarify the impacts of MBZ on NSCLC cell.

Methods

Cell proliferation, migration, and apoptosis were investigated via cell counting kit 8 (CCK-8) assay, Transwell assay, colony formation assay, wound-healing assay, and flow cytometry. Reactive oxygen species (ROS) were detected with a multifunctional microplate reader. Markers of cell migration and apoptosis were detected with Western blotting. The transcriptional activity of STAT3 was detected via luciferase assay. ROS scavenger N-acetylcysteine (NAC) was used to determine the effect of MBZ on NSCLC via ROS-regulated STAT3 inactivation and apoptosis. A xenograft model was constructed in vivo to investigate the role of MBZ in NSCLC tumor growth.

Results

The findings demonstrated that MBZ inhibited NSCLC cell proliferation and migration while promoting apoptosis through triggering ROS generation. In addition, the Janus kinase 2 (JAK2)-STAT3 signaling pathway was abrogated with the treatment of MBZ. NAC could distinctly weaken MBZ-induced apoptosis and STAT3 inactivation. Moreover, MBZ inhibited the tumor growth of NSCLC in vivo.

Conclusions

In summary, MBZ inhibited NSCLC cell viability and migration by inducing cell apoptosis via the ROS-JAK2-STAT3 signaling pathway. These data provide a theoretical basis for the use of MBZ in treating NSCLC.

Arsenic trioxide alleviates atherosclerosis by inhibiting CD36-induced endocytosis and TLR4/NF-κB-induced inflammation in macrophage and ApoE-/- mice

BACKGROUND

Inflammation and lipid accumulation are key events in atherosclerosis progression. Despite arsenic trioxide's (ATO) toxicity, at appropriate doses, it is a useful treatment for various diseases treatment. ATO prevents vascular restenosis; however, its effects on atherosclerotic plaque development and instability remain unclear.

METHODS

ApoE-/- mice were fed high-fat diet for 4 months, and starting at the third month, ATO was intravenously administered every other day. Atherosclerotic lesion size, histological characteristics, and related protein and lipid profiles were assessed using samples from the aorta, carotid artery, and serum. The anti-inflammatory and anti-pyroptosis effects of ATO were investigated by stimulating RAW264.7 and THP-1 cell lines with oxidized low-density lipoprotein (ox-LDL) or lipopolysaccharide (LPS).

RESULTS

ATO reduced atherosclerotic lesion formation and plasma lipid levels in ApoE-/- mice. In the serum and aortic plaques, ATO reduced the levels of pro-inflammatory factors, including interleukin (IL) 6 and tumor necrosis factor α, but increased IL-10 levels. Mechanistically, ATO promoted the CD36-mediated internalization of ox-LDL in a peroxisome proliferator-activated receptor γ-dependent manner. Furthermore, ATO downregulated Toll-like receptor 4 (TLR4) expression in plaques and macrophages and inhibited p65 nuclear translocation and IκBα degradation. ATO reduced macrophage pyroptosis by downregulating NLR family pyrin domain-containing 3 (NLRP3) expression and caspase 1 activation.

CONCLUSION

ATO has potential atheroprotective effects, especially in macrophages. The mechanisms were inhibition of CD36-mediated foam cell formation and suppression of inflammatory responses and pyroptosis mediated by TLR4/nuclear factor κB and NLRP3 activation. Our findings provide evidence supporting the potential atheroprotective value of ATO.

Proteome signatures of joint toxicity to arsenic (As) and lead (Pb) in human brain organoids with optic vesicles

Arsenic (As) and lead (Pb) are toxins found in the natural surroundings, and the harmful health outcomes caused by the co-exposure of such toxins have become a considerable problem. However, the joint neurotoxicity of As and Pb to neurodevelopment and the underlying mechanisms remain unclear. Pluripotent stem cell-derived human brain organoids are emerging animal model alternatives for understanding neurological-related diseases. Therefore, we utilized brain organoids with optic vesicles (OVB-organoids) to systematically analyze the neurotoxicity of As and Pb. After 24 h of As and/or Pb exposure, hematoxylin-eosin staining revealed that As and Pb exposure could cause disorders in the structure of the ventricular zone and general cell disarrangement in OVB-organoids. Immunostaining displayed that OVB-organoids are more susceptible to As and Pb co-exposure than independent exposure in apoptosis, proliferation, and cell differentiation. Meanwhile, even though As and Pb could both hinder cell proliferation, contrary to Pb, As could induce an increasing proportion of mitotic (G2/M) cells. The proteome landscape of OVB-organoids illustrated that Pb synergized with As in G2/M arrest and the common role of As and Pb in carcinogenesis. Besides, proteomics analyses suggested the consequential role of autophagy and Wnt pathway in the neurotoxicity of As and Pb co-exposure. Overall, our findings provide penetrating insights into the cell cycle, carcinogenesis, autophagy, and Wnt pathway underlying the As and Pb binary exposure scenarios, which could enhance our understanding of the mixture neurotoxicity mechanisms.

TFEB and TFE3 cooperate in regulating inorganic arsenic-induced autophagy-lysosome impairment and immuno-dysfunction in primary dendritic cells

Arsenic (As) is a prevalent and hazardous environmental toxicant associated with cancer and various health problems, which has been shown suppressive effects on dendritic cells (DCs). Autophagy is essential for the innate and adaptive immune responses of DCs, and the transcription factors TFEB and TFE3 are key regulators of autophagic and lysosomal target genes. However, the detrimental alterations of the autophagy-lysosome pathway in As-exposed DCs and the possible coordinating roles of TFEB and TFE3 in the immune dysfunction of this cell are less understood. In this paper, we found that As exposure significantly impaired lysosomal number, lysosomal acidic environment, and lysosomal membrane permeabilization, which might lead to blocked autophagic flux in cultured DCs. Furthermore, our results confirmed that TFEB or TFE3 knockdown exacerbated the disorders of lysosome and the blockade of autophagic flux in As-exposed DCs, and also enhanced the inhibitory expression of co-stimulatory molecules Cd80 and Cd83; adhesion molecule Icam1; cytokines TNF-α, IL-1β, and IL-6; chemokine receptor Ccr7; and antigen-presenting molecules MHC II and MHC I. By contrast, overexpression of TFEB or TFE3 partially alleviated the above-mentioned impairment of DCs by inorganic As exposure. In conclusion, these findings reveal a previously unappreciated inhibition of lysosome-mediated degradation and damage of lysosomal membrane integrity leading to dysregulated autophagy and impaired immune functions of DCs by arsenicals, and also suggest TFEB and TFE3 as potential therapeutic targets for ameliorating As toxicity.

Dapagliflozin alleviates arsenic trioxide-induced hepatic injury in rats via modulating PI3K/AkT/mTOR, STAT3/SOCS3/p53/MDM2 signaling pathways and miRNA-21, miRNA-122 expression

Dapagliflozin (DPG) is a sodium-glucose co-transporter 2 inhibitor that is commonly used in the treatment of type 2 diabetes. However, studies have shown that DPG has a protective effect under a variety of experimental conditions through its antioxidative and anti-inflammatory properties. DPG's effect on experimental hepatotoxicity caused by arsenic trioxide (ATO) has yet to be investigated. The purpose of this study was to investigate the protective effect of DPG in preventing hepatic damage caused by ATO and discover the underlying mechanisms. The effect of DPG (1 mg/kg, orally) on ATO (5 mg/kg, i.p.)-induced hepatic injury was evaluated in rats. Serum liver function parameters, as well as oxidative stress biomarkers and inflammatory cytokine levels were assessed. Histopathological changes in the liver were detected using H&E staining. Using Western blotting and PCR techniques, the molecular mechanisms of DPG in ameliorating hepatic injury were investigated. DPG improved liver function by inhibiting histopathological changes, decreasing levels of hepatic function and toxicity parameters measured in both serum and tissues, and exhibiting antioxidant and anti-inflammatory effects, according to the findings. Consistent with the PCR results, DPG also decreased the expression of LC3-II, micro-RNA-122, and micro-RNA-21 while increased the expression of SOCS3. Furthermore, according to western blotting results, DPG was able to reduce the protein expression of AKT, mTOR, PI3K, and STAT3. Although further clinical research is necessary, this study highlights the potential of DPG in preventing liver damage in a rat model of hepatotoxicity induced by ATO.

Akt Signaling and Nitric Oxide Synthase as Possible Mediators of the Protective Effect of N-acetyl-L-cysteine in Prediabetes Induced by Sucrose

The aim of this work was to evaluate possible mechanisms involved in the protective effect of N-acetyl-L-cysteine (NAC) on hepatic endocrine-metabolic, oxidative stress, and inflammatory changes in prediabetic rats. For that, normal male Wistar rats (60 days old) were fed for 21 days with 10% sucrose in their drinking water and 5 days of NAC administration (50 mg/kg, i.p.) and thereafter, we determined: serum glucose, insulin, transaminases, uric acid, and triglyceride levels; hepatic fructokinase and glucokinase activities, glycogen content, lipogenic gene expression; enzymatic and non-enzymatic oxidative stress, insulin signaling pathway, and inflammatory markers. Results showed that alterations evinced in sucrose-fed rats (hypertriglyceridemia, hyperinsulinemia, and high liver fructokinase activity together with increased liver lipogenic gene expression and oxidative stress and inflammatory markers) were prevented by NAC administration. P-endothelial nitric oxide synthase (P-eNOS)/eNOS and pAKT/AKT ratios, decreased by sucrose ingestion, were restored after NAC treatment. In conclusion, the results suggest that NAC administration improves glucose homeostasis, oxidative stress, and inflammation in prediabetic rats probably mediated by modulation of the AKT/NOS pathway. Administration of NAC may be an effective complementary strategy to alleviate or prevent oxidative stress and inflammatory responses observed in type 2 diabetes at early stages of its development (prediabetes).

Dictamnine Ameliorates DNFB-Induced Atopic Dermatitis Like Skin Lesions in Mice by Inhibiting M1 Macrophage Polarization and Promoting Autophagy

Autophagy and M1 macrophage polarization play important roles in the regulation of inflammation in atopic dermatitis (AD). Dictamnine is one of the main ingredients in Cortex Dictamni, a widely used traditional Chinese medicine for the treatment of dermatitis. In the present study, we investigated the anti-inflammatory effects of dictamnine on AD like skin lesions and M1 macrophage polarization. A 2,4-dinitrofluorobenzene (DNFB) triggered AD like skin lesions models in mice was established to identify the ameliorative effects of dictamnine on AD in vivo. In addition, an M1 macrophage polarization model was co-stimulated by lipopolysaccharide (LPS) and interferon-γ (IFN-γ) using phorbol myristate acetate (PMA) differentiated THP-1 cells, to investigate the effect of dictamnine on promoting autophagy and inhibiting inflammatory factor release. Dictamnine suppressed DNFB-induced skin inflammation by inhibiting M1 macrophage polarization, up-regulating the expression of microtubule-associated protein 1A/1B-light chain 3 (LC3) expression, and promoting macrophage autophagy at inflammatory sites. Dictamnine also could reduce the release of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), and interleukin-8 (IL-8), and down-regulate the mRNA expression of these genes in LPS-IFN-γ triggered M1 polarized macrophages. Dictamnine ameliorates AD like skin lesions by inhibiting M1 macrophage polarization and promoting autophagy. Hence, dictamnine is expected to be a potential therapeutic candidate for AD.

Novel treatment from a botanical formulation Si-Miao-Yong-an decoction inhibits vasa vasorum angiogenesis and stabilizes atherosclerosis plaques via the Wnt1/β-catenin signalling pathway

CONTEXT

Si-Miao-Yong-An (SMYA) has been widely used for the clinical treatment of atherosclerosis (AS). Yet, its complete mechanism of action is not fully understood.

OBJECTIVE

To investigate the mechanism by which SMYA stabilizes AS plaques from the perspective of inhibiting vasa vasorum (VV) angiogenesis.

MATERIALS AND METHODS

We used male ApoE-/- mice to establish an AS model. The mice were divided into model, SMYA (11.7 mg/kg/d), and simvastatin (SVTT) (2.6 mg/kg/d) groups. Mice were given SMYA or SVTT by daily gavage for 8 weeks. HE staining, immunofluorescence double-labelling staining, and immunohistochemical staining were used to observe the pathological changes in the plaques. Finally, the protein and mRNA expression levels of the Wnt1/β-catenin signalling pathway were detected by Western blot and qRT-PCR, respectively.

RESULTS

SMYA significantly attenuated cholesterol crystallization, and lipid accumulation in AS plaques, resulting in smaller plaque size (0.25 mm2 vs. 0.46 mm2), and lowering ratio of plaque to lumen area (20.04% vs. 38.33%) and VV density (50.64/mm2 vs. 98.02/mm2). Meanwhile, SMYA suppressed both the positive area percentage of Wnt1 (2.53 vs. 3.56), β-catenin (3.33 vs. 5.65) and Cyclin D1 (2.10 vs. 3.27) proteins in the aortic root plaques, and mRNA expression of Wnt1 (1.38 vs. 2.09), β-catenin (2.05 vs. 3.25) and Cyclin D1 (1.39 vs. 2.57).

DISCUSSION AND CONCLUSIONS

SMYA has a protective effect against AS, which may be related to its anti-VV angiogenesis in plaques, suggesting that SMYA has the potential as a novel botanical formulation in the treatment of AS.

Arsenic and Tau Phosphorylation: a Mechanistic Review

Arsenic poisoning can affect the peripheral nervous system and cause peripheral neuropathy. Despite different studies on the mechanism of intoxication, the complete process is not explained yet, which can prevent further intoxication and produce effective treatment. In the following paper, we would like to consider the idea that arsenic might cause some diseases via inflammation induction, and tauopathy in neurons. Tau protein, one of the microtubule-associated proteins expressed in neurons, contributes to neuronal microtubules structure. Arsenic may be involved in cellular cascades involved in modulating tau function or hyperphosphorylation of tau protein, which ultimately leads to nerve destruction. For proof of this assumption, some investigations have been planned to measure the association between arsenic and quantities of phosphorylation of tau protein. Additionally, some researchers have investigated the association between microtubule trafficking in neurons and the levels of tau protein phosphorylation. It should be noticed that changing tau phosphorylation in arsenic toxicity may add a new feature to understanding the mechanism of poisonousness and aid in discovering novel therapeutic candidates such as tau phosphorylation inhibitors for drug development.

Blockade of CXCR4 promotes macrophage autophagy through the PI3K/AKT/mTOR pathway to alleviate coronary heart disease

OBJECTIVE

Autophagy is important in regulating inflammation and cholesterol efflux, suggesting that targeting autophagy may slow down atherosclerosis (AS). Since the pathological basis of coronary artery disease (CAD) is atherosclerosis, it is crucial to investigate the role of autophagy in atherosclerosis. This study aimed to investigate the role of the chemokine CXC chemokine receptor 4 (CXCR4) in promoting macrophage autophagy through the phosphoinositide-3 kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway to alleviate coronary artery disease.

METHODS

The human left coronary artery and myocardium were collected to detect CXCR4, MAP1LC3(LC3) and SQSTM1(p62) expression. ApoE-/- mice were used to establish an atherosclerosis mice model, while human monocytes (THP-1) were used to establish a foam cell model and co-cultured with foam cells using siRNACXCR4. Western blotting was conducted to quantify CXCR4, PI3K/AKT/mTOR pathway protein, LC3, Beclin1 and p62 protein levels. The left coronary artery from humans and mouse aorta and myocardium were stained with Hematoxylin and Eosin (H&E), macrophages with Oil Red O staining and foam cells were assessed by Movat's staining. CXCR4 levels, PI3K/AKT/mTOR pathway protein, LC3 and p62 were detected by immunohistochemistry (IHC) and immunofluorescence assays. Detection of autophagosomes in macrophages using transmission electron microscopy. We further assessed whether the effect of CXCR4-mediated macrophage autophagy on the formation of atherosclerosis and structural changes in the myocardium was mediated via the PI3K/AKT/mTOR signaling pathway.

RESULTS

CXCR4 and p62 proteins were upregulated in human coronary lesions, mouse aorta, myocardial tissue, and foam cells, while LC3II/LC3I was downregulated. p85 (P-PI3K), Ser473 (P-AKT), and Ser2448 (P-mTOR) phosphorylated proteins associated with the PI3K/AKT/mTOR pathway were detected in AS and foam cell models. Upregulated CXCR4 inhibited autophagy of macrophages and increased the severity of atherosclerotic lesions. After specific knockdown of CXCR4 by adeno-associated virus (AAV9-CXCR4-RNAi) and siRNACXCR4, the above indicators were reversed, macrophage autophagy was promoted, the severity of atherosclerotic lesions was reduced, and the disorganized arrangement of myocardial architecture was improved.

CONCLUSION

Knockdown of CXCR4 reduces the extent of coronary artery disease by promoting macrophage autophagy through the PI3K/AKT/mTOR pathway to attenuate atherosclerosis.

TFEB SUMOylation in macrophages accelerates atherosclerosis by promoting the formation of foam cells through inhibiting lysosomal activity

Atherosclerosis (AS) is a serious cardiovascular disease. One of its hallmarks is hyperlipidemia. Inhibiting the formation of macrophage foam cells is critical for alleviating AS. Transcription factor EB (TFEB) can limit the formation of macrophage foam cells by upregulating lysosomal activity. We examined whether TFEB SUMOylation is involved in this progress during AS. In this study, we investigated the role of TFEB SUMOylation in macrophages in AS using TFEB SUMOylation deficiency Ldlr-/- (TFEB-KR: Ldlr-/-) transgenic mice and TFEB-KR bone marrow-derived macrophages. We observed that TFEB-KR: Ldlr-/- atherosclerotic mice had thinner plaques and macrophages with higher lysosomal activity when compared to WT: Ldlr-/- mice. TFEB SUMOylation in macrophages decreased after oxidized low-density lipoprotein (OxLDL) treatment in vitro. Compared with wild type macrophages, TFEB-KR macrophages exhibited less lipid deposition after OxLDL treatment. Our study demonstrated that in AS, deSUMOylation of TFEB could inhibit the formation of macrophage foam cells through enhancing lysosomal biogenesis and autophagy, further reducing the accumulation of lipids in macrophages, and ultimately alleviating the development of AS. Thus, TFEB SUMOylation can be a switch to modulate macrophage foam cells formation and used as a potential target for AS therapy.

Treponema pallidum membrane protein Tp47 induced autophagy and inhibited cell migration in HMC3 cells via the PI3K/AKT/FOXO1 pathway

The migratory ability of microglia facilitates their rapid transport to a site of injury to kill and remove pathogens. However, the effect of Treponema pallidum membrane proteins on microglia migration remains unclear. The effect of Tp47 on the migration ability and autophagy and related mechanisms were investigated using the human microglial clone 3 cell line. Tp47 inhibited microglia migration, the expression of autophagy-associated protein P62 decreased, the expression of Beclin-1 and LC3-II/LC3-I increased, and the autophagic flux increased in this process. Furthermore, autophagy was significantly inhibited, and microglial cell migration was significantly increased after neutralisation with an anti-Tp47 antibody. In addition, Tp47 significantly inhibited the expression of p-PI3K, p-AKT, and p-mTOR proteins, and the sequential activation of steps in the PI3K/AKT/mTOR pathways effectively prevented Tp47-induced autophagy. Moreover, Tp47 significantly inhibited the expression of p-FOXO1 protein and promoted FOXO1 nuclear translocation. Inhibition of FOXO1 effectively suppressed Tp47-induced activation of autophagy and inhibition of migration. Treponema pallidum membrane protein Tp47-induced autophagy and inhibited cell migration in HMC3 Cells via the PI3K/AKT/FOXO1 pathway. These data will contribute to understanding the mechanism by which T. pallidum escapes immune killing and clearance after invasion into the central nervous system.

E2F1-driven histone demethylase KDM6B enhances thyroid malignancy via manipulating TFEB-dependent autophagy axis

Aberrant epigenetic modifications or events regulate autophagy to influence tumor progression, which has gained increasing attention. KDM6B is an essential histone demethylase that participates in multiple processes of tumors, but its role in thyroid carcinoma (THCA) remains to be unknown. Here, in this study, we used the MTT assay to screen and validate that KDM6B is an essential demethylase for THCA. KDM6B promotes THCA proliferation, migration, invasion in vitro and in vivo. Transcriptional factor E2F1 directly binds to the promoter region of KDM6B and regulates its mRNA levels in THCA. E2F1 partially depended on KDM6B to exert its oncogenic functions. Mechanistically, KDM6B binds to TFEB promoter region and mediates the demethylation of H3K27me3. KDM6B depended on TFEB to activate a series of lysosomal-related genes. KDM6B enhances autophagy process, as evidenced by elevated p62 and Beclin-1 proteins. KDM6B depended on TFEB-driven autophagy activity to accelerate THCA progression. Lastly, targeting autophagy with 3-MA could notably abrogate growth of KDM6Bhigh THCA, but has mild influence on KDM6Blow THCA. Together, this study identified KDM6B as an essential epigenetic regulator for THCA, functioning as an autophagy regulator. The fundamental mechanisms underlying E2F1/KDM6B/TFEB axis provided novel vulnerabilities for THCA treatment.

The Anti-atherosclerosis Mechanism of Ziziphora clinopodioides Lam. Based On Network Pharmacology

We investigated the mechanisms underlying the effects of Ziziphora clinopodioides Lam. (ZCL) on atherosclerosis (AS) using network pharmacology and in vitro validation.We collected the active components of ZCL and predicted their targets in AS. We constructed the protein-protein interaction, compound-target, and target-compound-pathway networks, and performed GO and KEGG analyses. Molecular docking of the active components and key targets was constructed with Autodock and Pymol software. Validation was performed with qRT-PCR, ELISA, and Western blot.We obtained 80 components of ZCL. The network analysis identified that 14 components and 37 genes were involved in AS. Then, 10 key nodes in the PPI network were identified as the key targets of ZCL because of their importance in network topology. The binding energy of 8 components (Cynaroside, α-Spinasterol, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin) to 4 targets (MMP9, TP53, AKT1, SRC) was strong and <-1 kJ/mol. In addition, 13 of the 14 components were flavonoids and thus total flavonoids of Ziziphora clinopodioides Lam. (ZCF) were used for in vitro validation. We found that ZCF reduced eNOS, P22phox, gp91phox, and PCSK9 at mRNA and protein levels, as well as the levels of IL-1β, TNF-α, and IL-6 proteins in vitro (P < 0.05).We successfully predicted the active components, targets, and mechanisms of ZCL in treating AS using network pharmacology. We confirmed that ZCF may play a role in AS by modulating oxidative stress, lipid metabolism, and inflammatory response via Cynaroside, Linarin, Kaempferide, Acacetin, Genkwanin, Chrysin, and Apiin.

CircRREB1 mediates lipid metabolism related senescent phenotypes in chondrocytes through FASN post-translational modifications

Osteoarthritis is a prevalent age-related disease characterized by dysregulation of extracellular matrix metabolism, lipid metabolism, and upregulation of senescence-associated secretory phenotypes. Herein, we clarify that CircRREB1 is highly expressed in secondary generation chondrocytes and its deficiency can alleviate FASN related senescent phenotypes and osteoarthritis progression. CircRREB1 impedes proteasome-mediated degradation of FASN by inhibiting acetylation-mediated ubiquitination. Meanwhile, CircRREB1 induces RanBP2-mediated SUMOylation of FASN and enhances its protein stability. CircRREB1-FASN axis inhibits FGF18 and FGFR3 mediated PI3K-AKT signal transduction, then increased p21 expression. Intra-articular injection of adenovirus-CircRreb1 reverses the protective effects in CircRreb1 deficiency mice. Further therapeutic interventions could have beneficial effects in identifying CircRREB1 as a potential prognostic and therapeutic target for age-related OA.

PCSK9 inhibitors suppress oxidative stress and inflammation in atherosclerotic development by promoting macrophage autophagy

OBJECTIVES

Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, a novel class of cholesterol-lowering drugs, can reduce atherosclerosis independent of systemic lipid changes. However, the mechanism by which PCSK9 inhibition protects against arteriosclerosis has not been fully elucidated. Recent evidence has demonstrated a correlation between PCSK9 inhibitors and oxidative stress, which accelerates atherosclerotic development. Moreover, an increasing number of studies have shown that autophagy protects the vasculature against atherosclerosis. Therefore, the aims of this study were to investigate the effect of PCSK9 inhibition on oxidative stress and autophagy in atherosclerosis and determine whether autophagy regulates PCSK9 inhibition-mediated oxidative stress and inflammation in macrophages.

METHODS

Male apolipoprotein E (ApoE)-/- mice were fed a high-fat diet (HFD) for 8 weeks and then received the PCSK9 inhibitor (evolocumab), vehicle, or evolocumab plus chloroquine (CQ) for another 8 weeks. ApoE-/- mice in the control group were fed a regular (i.e., non-high-fat) diet for 16 weeks. Additional in vitro experiments were performed in oxidized low-density lipoprotein (ox-LDL)-treated human acute monocytic leukemia cell line THP-1-derived macrophages to mimic the pathophysiologic process of atherosclerosis.

RESULTS

PCSK9 inhibitor treatment reduced oxidative stress, lipid deposition, and plaque lesion area and induced autophagy in HFD-fed ApoE-/- mice. Most importantly, the administration of chloroquine (CQ), an autophagy inhibitor, significantly reduced the beneficial effects of PCSK9-inhibitor treatment on oxidative stress, lipid accumulation, inflammation, and atherosclerotic lesions in HFD-fed ApoE-/- mice. The in vitro experiments further showed that the PCSK9 inhibitor enhanced autophagic flux in ox-LDL-treated THP-1-derived macrophages, as indicated by increases in the numbers of autophagosomes and autolysosomes. Moreover, the autophagy inhibitor CQ also reduced PCSK9 inhibition-mediated protection against oxidative stress, generation of reactive oxygen species (ROS) and inflammation in ox-LDL-treated THP-1-derived macrophages.

CONCLUSIONS

This study reveals a novel protective mechanism by which PCSK9 inhibition enhances autophagy and thereby reduces oxidative stress and inflammation in atherosclerosis.

The role of ROS/p38 MAPK/NLRP3 inflammasome cascade in arsenic-induced depression-/anxiety-like behaviors of mice

Arsenic pollution in groundwater remains a serious public health concern around the world. Recent years, arsenic-related neurological and psychiatric disorders have been reported increasingly. However, the exact mechanisms of it remains elusive. In this study, arsenic exposure through drinking water resulted in depression-/anxiety-like behaviors in mice accompanied by oxidative stress and NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome activation in prefrontal cortex (PFC) and hippocampus, two main affected areas found in neurobehavioral disorders. Intervention by NAC, a ROS scavenger, diminished the social behavior impairments in mice as well as ROS generation and NLRP3 inflammasome activation. Further study revealed that it was p38 MAPK signaling pathway that mediated ROS-induced NLRP3 inflammasome activation. Overall, our findings suggested that ROS/p38 MAPK/NLRP3 inflammasome cascade was involved in arsenic-induced depression-/anxiety-disorders. Furthermore, NAC might be a potential therapeutic agent for arsenic-induced depression-/anxiety-disorders by inhibiting both ROS generation and ROS-induced NLRP3 inflammasome activation.

Vinblastine resets tumor-associated macrophages toward M1 phenotype and promotes antitumor immune response

BACKGROUND

Massive tumor-associated macrophage (TAM) infiltration is observed in many tumors, which usually display the immune-suppressive M2-like phenotype but can also be converted to an M1-like antitumor phenotype due to their high degree of plasticity. The macrophage polarization state is associated with changes in cell shape, macrophage morphology is associated with activation status. M1 macrophages appeared large and rounded, while M2 macrophages were stretched and elongated cells. Manipulating cell morphology has been shown to affect the polarization state of macrophages. The shape of the cell is largely dependent on cytoskeletal proteins, especially, microtubules. As a microtubule-targetting drug, vinblastine (VBL) has been used in chemotherapy. However, no study to date has explored the effect of VBL on TAM shape changes and its role in tumor immune response.

METHOD

We used fluorescent staining of the cytoskeleton and quantitative analysis to reveal the morphological differences between M0, M1, M2, TAM and VBL-treated TAM. Flow cytometry was used to confirm the polarization states of these macrophages using a cell surface marker-based classification. In vivo antibody depletion experiments in tumor mouse models were performed to test whether macrophages and CD8+ T cell populations were required for the antitumor effect of VBL. VBL and anti-PD-1 combination therapy was then investigated in comparison with monotherapy. RNA-seq of TAM of treated and untreated with VBL was performed to explore the changes in pathway activities. siRNA mediated knockdown experiments were performed to verify the target pathway that was affected by VBL treatment.

RESULTS

Here, we showed that VBL, an antineoplastic agent that destabilizes microtubule, drove macrophage polarization into the M1-like phenotype both in vitro and in tumor models. The antitumor effect of VBL was attenuated in the absence of macrophages or CD8+ T cells. Mechanistically, VBL induces the activation of NF-κB and Cyba-dependent reactive oxygen species generation, thus polarizing TAMs to the M1 phenotype. In parallel, VBL promotes the nuclear translocation of transcription factor EB, inducing lysosome biogenesis and a dramatic increase in phagocytic activity in macrophages.

CONCLUSIONS

This study explored whether manipulating cellular morphology affects macrophage polarization and consequently induces an antitumor response. Our data reveal a previously unrecognized antitumor mechanism of VBL and suggest a drug repurposing strategy combining VBL with immune checkpoint inhibitors to improve malignant tumor immunotherapy.

Dysregulation of Histone Deacetylases Inhibits Trophoblast Growth during Early Placental Development Partially through TFEB-Dependent Autophagy-Lysosomal Pathway

Dysregulated biological behaviors of trophoblast cells can result in recurrent spontaneous abortion (RSA)-whose underlying etiology still remains insufficient. Autophagy, a conserved intracellular physiological process, is precisely monitored throughout whole pregnancy. Although the exact mechanism or role remains elusive, epigenetic modification has emerged as an important process. Herein, we found that a proportion of RSA patients exhibited higher levels of autophagy in villus tissues compared to controls, accompanied with impaired histone deacetylase (HDAC) expression. The purpose of this study is to explore the connection between HDACs and autophagy in the pathological course of RSA. Mechanistically, using human trophoblast cell models, treatment with HDAC inhibitor (HDACI)-trichostatin A (TSA) can induce autophagy by promoting nuclear translocation and transcriptional activity of the central autophagic regulator transcription factor EB (TFEB). Specifically, overactivated autophagy is involved in the TSA-driven growth inhibition of trophoblast, which can be partially reversed by the autophagy inhibitor chloroquine (CQ) or RNA interference of TFEB. In summary, our results reveal that abnormal acetylation and autophagy levels during early gestation may be associated with RSA and suggest the potential novel molecular target TFEB for RSA treatment.

Arsenic Inhibits Proliferation and Induces Autophagy of Tumor Cells in Pleural Effusion of Patients with Non-Small Cell Lung Cancer Expressing EGFR with or without Mutations via PI3K/AKT/mTOR Pathway

To clarify whether arsenic could exert inhibitory effects on tumor cells in pleural effusions of patients with non-small cell lung cancer (NSCLC), 36 NSCLC pleural effusion samples were collected from Changzheng Hospital and Ruijin Hospital, from 2019 to 2022. The genotype of epidermal growth factor receptor (EGFR) was identified. Tumor cells were isolated and treated with arsenic trioxide (ATO) or/and gefitinib. Additionally, six patients were intrapleurally administrated with ATO. Results showed that 25 samples bore EGFR wild type (WT) and 11 harbored EGFR mutations, including 6 with L858R, 3 with ΔE746-A750, and 2 with T790M. ATO diminished the number of tumor cells from patients with WT and mutant EGFR, down-regulated the expression or phosphorylation of EGFR, pmTOR, PI3K, PTEN, and p4E-BP1, and up-regulated the expression of LC3. Immunofluorescent experiments showed that ATO enhanced LC3 and P62. By contrast, gefitinib was only effective in those harboring EGFR sensitizing mutations. Notably, in patients with intrapleural ATO injection, the pleural effusion underwent a bloody to pale yellow color change, the volume of the pleural effusion was reduced, and the number of the tumor cells was significantly reduced. In conclusion, arsenic is effective against NSCLC with various EGFR genotypes in vitro and in vivo, and potentially circumvents gefitinib resistance.

Rapamycin Inhibits Osteoclastogenesis and Prevents LPS-Induced Alveolar Bone Loss by Oxidative Stress Suppression

Periodontitis is a progressive inflammatory skeletal disease characterized by periodontal tissue destruction, alveolar bone resorption, and tooth loss. Chronic inflammatory response and excessive osteoclastogenesis play essential roles in periodontitis progression. Unfortunately, the pathogenesis that contributes to periodontitis remains unclear. As a specific inhibitor of the mTOR (mammalian/mechanistic target of rapamycin) signaling pathway and the most common autophagy activator, rapamycin plays a vital role in regulating various cellular processes. The present study investigated the effects of rapamycin on osteoclast (OC) formation in vitro and its effects on the rat periodontitis model. The results showed that rapamycin inhibited OC formation in a dose-dependent manner by up-regulating the Nrf2/GCLC signaling pathway, thus suppressing the intracellular redox status, as measured by 2',7'-dichlorofluorescein diacetate and MitoSOX. In addition, rather than simply increasing the autophagosome formation, rapamycin increased the autophagy flux during OC formation. Importantly, the anti-oxidative effect of rapamycin was regulated by an increase in autophagy flux, which could be attenuated by blocking autophagy with bafilomycin A1. In line with the in vitro results, rapamycin treatment attenuated alveolar bone resorption in rats with lipopolysaccharide-induced periodontitis in a dose-dependent manner, as assessed by micro-computed tomography, hematoxylin-eosin staining, and tartrate-resistant acid phosphatase staining. Besides, high-dose rapamycin treatment could reduce the serum levels of proinflammatory factors and oxidative stress in periodontitis rats. In conclusion, this study expanded our understanding of rapamycin's role in OC formation and protection from inflammatory bone diseases.

Naringenin facilitates M2 macrophage polarization after myocardial ischemia-reperfusion by promoting nuclear translocation of transcription factor EB and inhibiting the NLRP3 inflammasome pathway

Myocardial ischemia-reperfusion injury (MIRI) remains an unsolved puzzle in medical circles. Naringenin (NAR) is a flavonoid with cardioprotective potential. The purpose of this article was to discuss the protective mechanism of NAR in MIRI by regulating macrophage polarization. The MIRI mouse model was established and perfused with NAR before surgery. In the in vitro experiment, macrophages RAW264.7 were treated with lipopolysaccharide to induce M1 polarization after pretreatment with NAR. Rescue experiments were carried out to validate the functions of transcription factor EB (TFEB), the NLR pyrin domain containing 3 (NLRP3) inflammasome, and autophagy in macrophage polarization. NAR reduced histopathological injury and infarction of myocardial tissues in MIRI mice, inhibited M1 polarization and promoted M2 polarization of macrophages, diminished levels of pro-inflammatory factors, and augmented levels of anti-inflammatory factors. NAR facilitated TFEB nuclear translocation and inhibited the NLRP3 inflammasome pathway. Silencing TFEB or Nigericin partly nullified the effect of NAR on macrophage polarization. NAR increased autophagosome formation, autophagy flux, and autophagy level. Autophagy inhibitor 3-methyladenine partly invalidated the inhibition of NAR on the NLRP3 inflammasome pathway. In animal experiments, NAR protected MIRI mice through the TFEB-autophagy-NLRP3 inflammasome pathway. Collectively, NAR inhibited NLRP3 inflammasome activation and facilitated M2 macrophage polarization by stimulating TFEB nuclear translocation, thus protecting against MIRI.

The Role of Macrophages in Atherosclerosis: Pathophysiologic Mechanisms and Treatment Considerations

Atherosclerotic diseases are a leading cause of morbidity and mortality worldwide, despite the recent diagnostic and therapeutic advances. A thorough understanding of the pathophysiologic mechanisms is thus essential to improve the care of affected individuals. Macrophages are crucial mediators of the atherosclerotic cascade, but their role has not been fully elucidated. The two main subtypes, tissue-resident and monocyte-derived macrophages, have distinct functions that contribute to atherosclerosis development or regression. Since polarization of macrophages to an M2 phenotype and induction of macrophage autophagy have been demonstrated to be atheroprotective, targeting these pathways could represent an appealing approach. Interestingly, macrophage receptors could act as drug targets, as seen in recent experimental studies. Last but not least, macrophage-membrane-coated carriers have been investigated with encouraging results.

Candidate SNP Markers Significantly Altering the Affinity of TATA-Binding Protein for the Promoters of Human Hub Genes for Atherogenesis, Atherosclerosis and Atheroprotection

Atherosclerosis is a systemic disease in which focal lesions in arteries promote the build-up of lipoproteins and cholesterol they are transporting. The development of atheroma (atherogenesis) narrows blood vessels, reduces the blood supply and leads to cardiovascular diseases. According to the World Health Organization (WHO), cardiovascular diseases are the leading cause of death, which has been especially boosted since the COVID-19 pandemic. There is a variety of contributors to atherosclerosis, including lifestyle factors and genetic predisposition. Antioxidant diets and recreational exercises act as atheroprotectors and can retard atherogenesis. The search for molecular markers of atherogenesis and atheroprotection for predictive, preventive and personalized medicine appears to be the most promising direction for the study of atherosclerosis. In this work, we have analyzed 1068 human genes associated with atherogenesis, atherosclerosis and atheroprotection. The hub genes regulating these processes have been found to be the most ancient. In silico analysis of all 5112 SNPs in their promoters has revealed 330 candidate SNP markers, which statistically significantly change the affinity of the TATA-binding protein (TBP) for these promoters. These molecular markers have made us confident that natural selection acts against underexpression of the hub genes for atherogenesis, atherosclerosis and atheroprotection. At the same time, upregulation of the one for atheroprotection promotes human health.

Arsenite exposure disturbs maternal-to-zygote transition by attenuating H3K27ac during mouse preimplantation development

Arsenite is commonly used as an insecticide, antiseptic and herbicide. It can enter the food chain via through soil contamination, and harm human health, including the reproductive systems. Early embryos, as the initial stage of mammalian life, are very sensitive to the environmental toxins and pollutants. However, whether and how arsenite disturbs the early embryo development remains unclear. Our study used mouse early embryos as a model and revealed that arsenite exposure did not cause reactive oxygen species production, DNA damage or apoptosis. However, arsenite exposure arrested embryonic development at the 2-cell stage by altering gene expression patterns. The transcriptional profile in the disrupted embryos showed abnormal maternal-to-zygote transition (MZT). More importantly, arsenite exposure attenuated H3K27ac modification enrichment at the promoter region of Brg1, a key gene for MZT, which inhibited its transcription, and further affected MZT and early embryonic development. In conclusion our study highlights arsenite exposure affects MZT by reducing the enrichment of H3K27ac on the embryonic genome, and ultimately induces early embryonic development arrest at the 2-cell stage.

Drug-induced oxidative stress in cancer treatments: Angel or devil?

Oxidative stress (OS), defined as redox imbalance in favor of oxidant burden, is one of the most significant biological events in cancer progression. Cancer cells generally represent a higher oxidant level, which suggests a dual therapeutic strategy by regulating redox status (i.e., pro-oxidant therapy and/or antioxidant therapy). Indeed, pro-oxidant therapy exhibits a great anti-cancer capability, attributing to a higher oxidant accumulation within cancer cells, whereas antioxidant therapy to restore redox homeostasis has been claimed to fail in several clinical practices. Targeting the redox vulnerability of cancer cells by pro-oxidants capable of generating excessive reactive oxygen species (ROS) has surfaced as an important anti-cancer strategy. However, multiple adverse effects caused by the indiscriminate attacks of uncontrolled drug-induced OS on normal tissues and the drug-tolerant capacity of some certain cancer cells greatly limit their further applications. Herein, we review several representative oxidative anti-cancer drugs and summarize their side effects on normal tissues and organs, emphasizing that seeking a balance between pro-oxidant therapy and oxidative damage is of great value in exploiting next-generation OS-based anti-cancer chemotherapeutics.

JI017 Induces Cell Autophagy and Apoptosis via Elevated Levels of Reactive Oxygen Species in Human Lung Cancer Cells

Lung cancer is one of the most common malignant tumors and a leading cause of cancer-related death in the worldwide. Various anticancer drugs, such as cisplatin and pemetrexed, have been developed for lung cancer treatment but due their drug resistance and side effects, novel treatments need to be developed. In this study, the efficacy of the natural drug JI017, which is known to have few side effects, was tested in lung cancer cells. JI017 inhibited A549, H460, and H1299 cell proliferation. JI017 induced apoptosis, regulated apoptotic molecules, and inhibited colony formation. Additionally, JI017 increased intracellular ROS generation. JI017 downregulated PI3K, AKT, and mTOR expression. JI017 increased the cytosolic accumulation of LC3. We found that JI017 promoted apoptosis through ROS-induced autophagy. Additionally, the xenograft tumor size was smaller in JI017-treated mice. We found that JI017 treatment increased MDA concentrations, decreased Ki-67 protein levels, and increased cleaved caspase-3 and LC3 levels in vivo. JI017 decreased cell proliferation and increased apoptosis by inducing autophagy signaling in H460 and H1299 lung cancer cells. Targeting JI017 and autophagy signaling could be useful in lung cancer treatment.

Maltol attenuates polystyrene nanoplastic-induced enterotoxicity by promoting AMPK/mTOR/TFEB-mediated autophagy and modulating gut microbiota

The production and application of nanoplastics has been increased during decades, and the enterotoxicity caused by their bioaccumulation has attracted vast attention. Maltol was proved to exert a protective effect on gut damage induced by carbon tetrachloride and cisplatin, indicating its confrontation with nanoplastics-induced intestinal toxicity. To explore the ameliorative effects of maltol on polystyrene nanoplastics (PS)-mediated enterotoxicity and the underlying mechanism, the mice were exposed to PS (100 mg/kg), combining with or without the treatment of maltol treatment at 50 and 100 mg/kg. We found PS exposure caused intestinal barrier damage and enterocyte apoptosis, while lysosomal dysfunction and autophagic substrate degradation arrest in enterocytes of mice were also observed. In addition, PS exacerbated the disturbance of the intestinal microbial community, affected the abundance of lysosome and apoptosis-related bacterial genes, and decreased the number of known short-chain fatty acid (SCFA) producing bacteria. However, those alterations were improved by the maltol treatment. Maltol also protected the human intestinal Caco-2 cells from PS-induce damages. Mechanistic studies showed maltol promoted TFEB nuclear translocation through the AMPK/mTOR signaling pathway to restore lysosomal function and reduce autophagy dependent apoptosis. The findings in the present work might help to elucidate the potential molecular mechanisms of PS-induced enterotoxicity. For the first time to our knowledge, the protective effect of maltol on PS-induced intestinal injury was studied from multiple perspectives, which provided a potential therapeutic approach for diseases caused by environmental pollution.

Co-exposure to arsenic and fluoride to explore the interactive effect on oxidative stress and autophagy in myocardial tissue and cell

Co-contamination of arsenic and fluoride is widely distributed in groundwater. However, little is known about the interactively influence of arsenic and fluoride, especially the combined mechanism in cardiotoxicity. Cellular and animal models exposure to arsenic and fluoride were established to assess the oxidative stress and autophagy mechanism of cardiotoxic damage using the factorial design, a widely used statistical method for assessing two factor interventions. In vivo, combined exposure to high arsenic (50 mg/L) and high fluoride (100 mg/L) induced myocardial injury. The damage is accompanied by accumulation of myocardial enzyme, mitochondrial disorder, and excessive oxidative stress. Further experiment identified that arsenic and fluoride induced the accumulation of autophagosome and increased expression level of autophagy related genes during the cardiotoxicity process. These findings were further demonstrated through the in vitro model of arsenic and fluoride-treated the H9c2 cells. Additionally, combined of arsenic-fluoride exposure possesses the interactively influence on oxidative stress and autophagy, contributing to the myocardial cell toxicity. In conclusion, our data suggest that oxidative stress and autophagy are involved in the process of cardiotoxic injury, and that these indicators showed interaction effect in response to the combined exposure of arsenic and fluoride.