Mitochondria-dependent Apoptosis Research Articles

Structure and in vitro antiproliferative activity against breast cancer cells of the cell-wall polysaccharide from the marine bacterium Kangiella japonica KMM 3899T

Kangiella japonica KMM 3899T is a Gram-negative bacterium isolated from a sandy sediment sample collected from the Sea of Japan. Here the results of the structure and the biological activity against breast cancer cells of the cell-wall polysaccharide from K. japonica KMM 3899T have been described. The structure of the repeating unit of the polysaccharide was elucidated using chemical analysis and NMR spectroscopy:→4)-α-L-GalpNAc3AcA-(1 → 3)-α-D-GlcpNAc-(1 → 4)-β-D-GlcpNAc3NAcAN-(1→.The cell-wall polysaccharide had an antiproliferative effect against T-47D cells. Flow cytometric and Western blot analysis revealed that the polysaccharide induced S phase arrest and mitochondrial-dependent apoptosis.

Safranal alleviates pentetrazole-induced epileptic seizures in mice by inhibiting the NF-κB signaling pathway and mitochondrial-dependent apoptosis through GSK-3β inactivation

Ethnopharmacological relevanceSaffron, a traditional Chinese medicine, is derived from Crocus sativus L. stigmas and has been reported to possess neuroprotective properties and potentially contribute to the inhibition of apoptosis and inflammation. Safranal, a potent monothyral aldehyde, is a main component of saffron that has been reported to have antiepileptic activity. However, the specific mechanism by which safranal suppresses epileptic seizures via its antiapoptotic and anti-inflammatory properties is unclear. AimTo evaluate the effect of safranal on seizure severity, inflammation, and postictal neuronal apoptosis in a mouse model of pentetrazole (PTZ)-induced seizures and explore the underlying mechanism involved. Materials and methodsThe seizure stage and latency of stage 2 and 4 were quantified to assess the efficacy of safranal in mitigating PTZ-induced epileptic seizures in mice. Electroencephalography (EEG) was employed to monitor epileptiform afterdischarges in each experimental group. The cognitive abilities and motor functions of the mice were evaluated using the novel object recognition test and the open field test, respectively. Neurons were quantified using hematoxylin and eosin staining. Additionally, bioinformatics tools were utilized to predict the interactions between safranal and specific target proteins. Glycogen synthase kinase-3β (GSK-3β), mitochondrial apoptosis-related proteins, and inflammatory factor levels were analyzed through western blotting. Tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) concentrations in brain tissue were assessed by ELISA. ResultsSafranal decreased the average seizure stage and increased the lantency of stage 2 and 4 seizures in PTZ-induced epileptic mice. Additionally, safranal exhibited neuroprotective effects on hippocampal CA1 and CA3 neurons and reduced hyperactivity caused by postictal hyperexcitability. Bioinformatics analysis revealed that safranal can bind to five specific proteins, including GSK-3β. By promoting Ser9 phosphorylation and inhibiting GSK-3β activity, safranal effectively suppressed the NF-κB signaling pathway. Moreover, the findings indicate that safranal treatment can decrease TNF-α and IL-1β levels in the cerebral tissues of epileptic mice and downregulate mitochondrial apoptosis-related proteins, including Bcl-2, Bax, Bak, Caspase 9, and Caspase 3. ConclusionSafranal can suppress the NF-κB signaling pathway and mitochondrial-dependent apoptosis through GSK-3β inactivation, suggesting that it is a promising therapeutic agent for epilepsy treatment.

Hispidin Increases Cell Apoptosis and Ferroptosis in Prostate Cancer Cells Through Phosphatidylinositol-3-Kinase and Mitogen-activated Protein Kinase Signaling Pathway.

Chemotherapy is mainly used in the clinical treatment of prostate cancer. Different anticancer mechanisms can induce cell death in various cancers. Reactive oxygen species (ROS) play crucial roles in cell proliferation, differentiation, apoptosis, and signal transduction. It is widely accepted that ROS accumulation is closely related to chemical drug-induced cancer cell death. We utilized the MTT assay to detect changes in cell proliferation. Additionally, colony formation and wound healing assay were conducted to investigate the effect of hispidin on cell colony formation and migration ability. Fluorescence microscopy was used to detect intracellular and mitochondrial ROS levels, while western blot was used for detection of cell apoptosis. Hispidin treatment significantly decreased viability of PC3 and DU145 cancer cells but exhibited no cytotoxicity in WPMY-1 cells. Furthermore, hispidin treatment inhibited cell migration and colony formation and triggered cellular and mitochondrial ROS accumulation, leading to mitochondrial dysfunction and mitochondrion-dependent apoptosis. Moreover, hispidin treatment induced ferroptosis in PC3 cells. Scavenging of ROS with N-acetyl cysteine significantly inhibited hispidin-induced apoptosis by altering the expression of apoptosis-related proteins, such as cleaved caspase-3, 9, Bax, and Bcl2. Furthermore, hispidin treatment dramatically up-regulated MAPK (involving p38, ERK, and JNK proteins) and NF-kB signaling pathways while down-regulating AKT phosphorylation. Hispidin treatment also inhibited ferroptosis signaling pathways (involving P53, Nrf-2, and HO-1 proteins) in PC3 cells. In addition, inhibiting these signaling pathways via treatment with specific inhibitors significantly reversed hispidin-induced apoptosis, cellular ROS levels, mitochondrial dysfunction, and ferroptosis. Hispidin may represent a potential candidate for treating prostate cancer.

Capsaicin reverses cisplatin resistance in tongue squamous cell carcinoma by inhibiting the Warburg effect and facilitating mitochondrial-dependent apoptosis via the AMPK/AKT/mTOR axis.

Cisplatin is commonly used for the chemotherapy of tongue squamous cell carcinoma (TSCC); however, adverse side effects and drug resistance impact its therapeutic efficacy. Capsaicin is an active ingredient in chili peppers that exerts antitumor effects, whether it exerts antitumor effects on cisplatin-resistant cells remains unknown. Therefore, in this study, we investigated the effect of capsaicin on cisplatin resistance in TSCC cells and explored the underlying mechanisms. A cisplatin-resistant TSCC cell line was established by treated with increasing cisplatin concentrations. Combined treatment with cisplatin and capsaicin decreased the glucose consumption and lactate dehydrogenase activity and increased the adenosine triphosphate production both in vitro and in vivo, suggesting the inhibition of the Warburg effect. Moreover, this combined treatment induced cell apoptosis and significantly upregulated the levels of proapoptotic proteins, such as Bax, cleaved caspase-3, -7, and -9, and apoptosis-inducing factor. In contrast, levels of the antiapoptotic protein, Bcl-2, were downregulated. Additionally, LKB1 and AMPK activities were stimulated, whereas those of AKT and mTOR were suppressed. Notably, AMPK knockdown abolished the inhibitory effects of capsaicin and cisplatin on the AKT/mTOR signaling pathway and Warburg effect. Overall, combined treatment with capsaicin and cisplatin reversed cisplatin resistance by inhibiting the Warburg effect and facilitating mitochondrial-dependent apoptosis via the AMPK/AKT/mTOR axis. Our findings suggest combination therapy with capsaicin and cisplatin as a potentially novel strategy and highlight capsaicin as a promising adjuvant drug for TSCC treatment.

Reversible ON- and OFF-switch receptors Clec4G and Rab1A reveals the hormetic effects of polysaccharide in Aralia elata (Miq.) Seem

BackgroundNumerous studies indicate that natural polysaccharides have immune-enhancing effects as a host defense potentiator. Few reports are available on hormetic effects of natural polysaccharides, and the underlying mechanisms remain unclear. PurposeAELP-B6 (arabinose- and galactose-rich pectic polysaccharide) from Aralia elata (Miq.) Seem was taken as a case study to clarify the potential mechanism of hormetic effects of natural polysaccharides. MethodsThe pharmacodynamic effect of AELP-B6 was verified by constructing the CTX-immunosuppressive mouse model. The hormetic effects was explored by TMT-labeled proteomics, energy metabolism analysis, flow cytometry and western blot. The core-affinity target of AELP-B6 was determined by pull down, nanoLC-nanoESI-MS, CETSA, immunoblot and SPR assay. The RAW264.7Clec4G-RFP and RAW264.7Rab1A-RFP cell lines were simultaneously constructed to determine the affinity difference between AELP-B6 and targets by confocal laser scanning live-cell imaging. Antibody blocking assays were further used to verify the mechanism of hormetic effects. ResultsAELP-B6 at low and medium doses may maintain the structural integrity of thymus and spleen, increase the concentrations of TNF-α, IFN-γ, IL-3 and IL-8, and alleviate CTX-induced reduction of immune cell viability in vivo. Proteomics and energy metabolism analysis revealed that AELP-B6 regulate HIF-1α-mediated metabolic programming, causing Warburg effects in macrophages. AELP-B6 at low and medium doses promoted the release of intracellular immune factors, and driving M1-like polarization of macrophages. As a contrast, AELP-B6 at high dose enhanced the expression levels of apoptosis related proteins, indicating activation of the intrinsic apoptotic cascade. Two highly expressed transmembrane proteins in macrophages, Clec4G and Rab1A, were identified as the primary binding targets of AELP-B6 which co-localized with the cell membrane and directly impacted with immune cell activation and apoptosis. AELP-B6 exhibits affinity differences with Clec4G and Rab1A, which is the key to the hormetic effects. ConclusionWe observed hormesis of natural polysaccharide (AELP-B6) for the first time, and AELP-B6 mediates the hormetic effects through two dose-related targets. Low dose of AELP-B6 targets Clec4G, thereby driving the M1-like polarization via regulating NF-κB signaling pathway and HIF-1α-mediated metabolic programming, whereas high dose of AELP-B6 targets Rab1A, leading to mitochondria-dependent apoptosis.

YBX1 inhibits mitochondrial-mediated apoptosis in ischemic heart through the PI3K/AKT signaling pathway

Abstract Background Myocardial infarction (MI) is associated with higher morbidity and mortality in the world, especially in cold weather. YBX1 is an RNA-binding protein that is required for pathological growth of cardiomyocyte by regulating cell growth and protein synthesis. But YBX1, as an individual RNA-binding protein, regulates cardiomyocytes through signaling cascades during myocardial infarction remain largely unexplored. Methods In vivo, the mouse MI model was induced by ligating the left anterior descending coronary artery (LAD), and randomly divided into sham operation group, MI group, MI+ YBX1 knockdown/overexpression group and MI+ negative control (NC) group. The protective effect of YBX1 was verified by echocardiography and triphenyltetrazolium chloride staining. In vitro, mitochondrial-dependent apoptosis was investigated by using CCK8, TUNEL staining, reactive oxygen species (ROS) staining and JC-1 staining in hypoxic neonatal mouse cardiomyocytes (NMCMs). Results YBX1 expression of cardiomyocytes was downregulated in a mouse model and a cellular model on the ischemic condition. Compared to mice induced by MI, YBX1 overexpression mediated by adeno-associated virus serotype 9 (AAV9) vector reduced the infarcted size and improved cardiac function. Knockdown of endogenous YBX1 by shRNA partially aggravated ischemia-induced cardiac dysfunction. In hypoxic cardiomyocytes, YBX1 overexpression decreased lactic dehydrogenase (LDH) release, increased cell viability, and inhibited apoptosis by affecting the expression of apoptosis related proteins, while knockdown of endogenous YBX1 by siRNA had the opposite effect. Overexpression of YBX1 restored mitochondrial dysfunction in hypoxic NMCMs by increasing mitochondrial membrane potential and ATP content and decreasing ROS. In hypoxic NMCMs, YBX1 overexpression increased the expression of phosphorylated phosphatidylinositol 3 kinase (PI3K)/AKT, and the antiapoptosis effect of YBX1 was eliminated t by LY294002, PI3K/AKT inhibitor. Conclusion YBX1 protected the heart from ischemic damage by inhibiting the mitochondrial-dependent apoptosis through PI3K/AKT pathway. It is anticipated that YBX1 may serve as a novel therapeutic target for MI.

Spatiotemporal ATF3 Expression Determines VSMC Fate in Abdominal Aortic Aneurysm.

Abdominal aortic aneurysm (AAA) is a catastrophic disease with little effective therapy, likely due to the limited understanding of the mechanisms underlying AAA development and progression. ATF3 (activating transcription factor 3) has been increasingly recognized as a key regulator of cardiovascular diseases. However, the role of ATF3 in AAA development and progression remains elusive. Genome-wide RNA sequencing analysis was performed on the aorta isolated from saline or Ang II (angiotensin II)-induced AAA mice, and ATF3 was identified as the potential key gene for AAA development. To examine the role of ATF3 in AAA development, vascular smooth muscle cell-specific ATF3 knockdown or overexpressed mice by recombinant adeno-associated virus serotype 9 vectors carrying ATF3, or shRNA-ATF3 with SM22α (smooth muscle protein 22-α) promoter were used in Ang II-induced AAA mice. In human and murine vascular smooth muscle cells, gain or loss of function experiments were performed to investigate the role of ATF3 in vascular smooth muscle cell proliferation and apoptosis. In both Ang II-induced AAA mice and patients with AAA, the expression of ATF3 was reduced in aneurysm tissues but increased in aortic lesion tissues. The deficiency of ATF3 in vascular smooth muscle cell promoted AAA formation in Ang II-induced AAA mice. PDGFRB (platelet-derived growth factor receptor β) was identified as the target of ATF3, which mediated vascular smooth muscle cell proliferation in response to TNF-alpha (tumor necrosis factor-α) at the early stage of AAA. ATF3 suppressed the mitochondria-dependent apoptosis at the advanced stage by upregulating its direct target BCL2. Our chromatin immunoprecipitation results also demonstrated that the recruitment of NFκB1 and P300/BAF/H3K27ac complex to the ATF3 promoter induces ATF3 transcription via enhancer activation. NFKB1 inhibitor (andrographolide) inhibits the expression of ATF3 by blocking the recruiters NFKB1 and ATF3-enhancer to the ATF3-promoter region, ultimately leading to AAA development. Our results demonstrate a previously unrecognized role of ATF3 in AAA development and progression, and ATF3 may serve as a novel therapeutic and prognostic marker for AAA.

Pseudorabies virus gM and its homologous proteins in herpesviruses induce mitochondria-related apoptosis involved in viral pathogenicity.

Apoptosis is a critical host antiviral defense mechanism. But many viruses have evolved multiple strategies to manipulate apoptosis and escape host antiviral immune responses. Herpesvirus infection regulated apoptosis; however, the underlying molecular mechanisms have not yet been fully elucidated. Hence, the present study aimed to study the relationship between herpesvirus infection and apoptosis in vitro and in vivo using the pseudorabies virus (PRV) as the model virus. We found that mitochondria-dependent apoptosis was induced by PRV gM, a late protein encoded by PRV UL10, a virulence-related gene involved in enhancing PRV pathogenicity. Mechanistically, gM competitively combines with BCL-XL to disrupt the BCL-XL-BAK complex, resulting in BCL-2-antagonistic killer (BAK) oligomerization and BCL-2-associated X (BAX) activation, which destroys the mitochondrial membrane potential and activates caspase-3/7 to trigger apoptosis. Interestingly, similar apoptotic mechanisms were observed in other herpesviruses (Herpes Simplex Virus-1 [HSV-1], human cytomegalovirus [HCMV], Equine herpesvirus-1 [EHV-1], and varicella-zoster virus [VZV]) driven by PRV gM homologs. Compared with their parental viruses, the pathogenicity of PRV-ΔUL10 or HSV-1-ΔUL10 in mice was reduced with lower apoptosis and viral replication, illustrating that UL10 is a key virulence-related gene in PRV and HSV-1. Consistently, caspase-3 deletion also diminished the replication and pathogenicity of PRV and HSV-1 in vitro and in mice, suggesting that caspase-3-mediated apoptosis is closely related to the replication and pathogenicity of PRV and HSV-1. Overall, our findings firstly reveal the mechanism by which PRV gM and its homologs in several herpesviruses regulate apoptosis to enhance the viral replication and pathogenicity, and the relationship between gM-mediated apoptosis and herpesvirus pathogenicity suggests a promising approach for developing attenuated live vaccines and therapy for herpesvirus-related diseases.

Exploring the role of Prx II in mitigating endoplasmic reticulum stress and mitochondrial dysfunction in neurodegeneration

BackgroundNeurodegenerative diseases are increasingly recognized for their association with oxidative stress, which leads to progressive dysfunction and loss of neurons, manifesting in cognitive and motor impairments. This study aimed to elucidate the neuroprotective role of peroxiredoxin II (Prx II) in counteracting oxidative stress-induced mitochondrial damage, a key pathological feature of neurodegeneration.MethodsWe investigated the impact of Prx II deficiency on endoplasmic reticulum stress and mitochondrial dysfunction using HT22 cell models with knocked down and overexpressed Prx II. We observed alcohol-treated HT22 cells using transmission electron microscopy and monitored changes in the length of mitochondria-associated endoplasmic reticulum membranes and their contact with endoplasmic reticulum mitochondria contact sites (EMCSs). Additionally, RNA sequencing and bioinformatic analysis were conducted to identify the role of Prx II in regulating mitochondrial transport and the formation of EMCSs.ResultsOur results indicated that Prx II preserves mitochondrial integrity by facilitating the formation of EMCSs, which are essential for maintaining mitochondrial Ca2+ homeostasis and preventing mitochondria-dependent apoptosis. Further, we identified a novel regulatory axis involving Prx II, the transcription factor ATF3, and miR-181b-5p, which collectively modulate the expression of Armcx3, a protein implicated in mitochondrial transport. Our findings underscore the significance of Prx II in protecting neuronal cells from alcohol-induced oxidative damage and suggest that modulating the Prx II-ATF3-miR-181b-5p pathway may offer a promising therapeutic strategy against neurodegenerative diseases.ConclusionsThis study not only expands our understanding of the cytoprotective mechanisms of Prx II but also offers necessary data for developing targeted interventions to bolster mitochondrial resilience in neurodegenerative conditions.

Mitochondrial Fission in Nickel Nanoparticle-Induced Reproductive Toxicity: An In Vitro GC-1 Cell Study.

Reproductive disorders and declining fertility rates are significant public health concerns affecting birth rates and future populations. Male infertility, often due to spermatogenesis defects, may be linked to environmental pollutants like nickel nanoparticles (Ni NPs). Ni NPs are extensively utilized across different industries. Nevertheless, their potential adverse effects cannot be overlooked. Previous studies have linked the reproductive toxicity induced by Ni NPs with disturbances in mitochondrial function. Mitochondrial division/fusion dynamics are crucial to their proper function, yet little is known about how Ni NPs perturb these dynamics and whether such perturbation contributes to the impairment of the male reproductive system. Herein, we demonstrated that the exposure of Ni NPs to the mouse-derived spermatogonia cell line (GC-1 cells) triggered DRP1-mediated mitochondrial division and the enhanced impairment of mitochondria, consequently promoting mitochondria-dependent cell apoptosis. Notably, both the mitochondrial division inhibitor (Mdivi-1) and lentiviral-transfected cells with low expression of Dnm1l-DK in these cells could mitigate the toxic effects induced by Ni NPs, pointing to the potential role of mitochondrial dynamics in Ni NP-induced reproductive toxicity. Collectively, our work contributes to the understanding of the mechanisms by which Ni NPs can impact male reproductive function and identifies mitochondrial division as a potential target for intervention.

C-terminal region of Rv1039c (PPE15) protein of Mycobacterium tuberculosis targets host mitochondria to induce macrophage apoptosis.

Mycobacterium tuberculosis (Mtb) genome possesses a unique family called Proline-Glutamate/Proline-Proline-Glutamate (PE/PPE) gene family, exclusive to pathogenic mycobacterium. Some of these proteins are known to play role in virulence and immune response modulation, but many are still uncharacterized. This study investigated the role of C-terminal region of Rv1039c (PPE15) in inducing mitochondrial perturbations and macrophage apoptosis. Our in-silico studies revealed the disordered, coiled, and hydrophobic C-terminal region in Rv1039c has similarity with C-terminal of mitochondria-targeting pro-apoptotic host proteins. Wild type Rv1039c and C-terminal deleted Rv1039c (Rv1039c-/-Cterm) recombinant proteins were purified and their M. smegmatis knock-in strains were constructed which were used for in-vitro experiments. Confocal microscopy showed localization of Rv1039c to mitochondria of PMA-differentiated THP1 macrophages; and reduced mitochondrial membrane depolarization and production of mitochondrial superoxides were observed in response to Rv1039c-/-Cterm in comparison to full-length Rv1039c. The C-terminal region of Rv1039c was found to activate caspases 3, 7 and 9 along with upregulated expression of pro-apoptotic genes like Bax and Bim. Rv1039c-/-Cterm also reduced the Cytochrome-C release from the mitochondria and the expression of AnnexinV/PI positive and TUNEL positive cells as compared to Rv1039c. Additionally, Rv1039c was observed to upregulate the TLR4-NF-κB-TNF-α signalling whereas the same was downregulated in response to Rv1039c-/-Cterm. These findings suggested that the C-terminal region of Rv1039c is a molecular mimic of pro-apoptotic host proteins which induce mitochondria-dependent macrophage apoptosis and evoke host immune response. These observations enhance our understanding about the role of PE/PPE proteins at host-pathogen interface.

Antitumor effects of polydopamine coated hydroxyapatite nanoparticles and its mechanism: Mitochondria-targeted ROS and calcium channels

Nano hydroxyapatite (nHA) has been acknowledged for its inhibition efficiency on tumor cells and its excellent biocompatibility for normal tissue and cells. However, the low inhibitory efficiency of tumor cells and the ambiguous inhibitory mechanism limited its further application. In this work, four kinds of nHA with different sizes was prepared, and the one with the highest inhibition efficiency on 4T1 cells was screened as a substrate for developing the nanoparticles coated with polydopamine (PDA) coating, which was named nHA-PDA. Both in vivo and in vitro experiments were employed, and the results showed significantly higher inhibitory activity against 4T1 cells and 4T1-bared tumors by nHA-PDA. Further investigation revealed that the oxidative stress induced by PDA results in a large Reactive Oxygen Species (ROS) accumulation, thus triggering the mitochondria-dependent apoptosis pathway ROS-JNK/MAPK and inducing the cascade reaction of inhibiting the anti-apoptosis protein-Bcl-2 expression and activating the expression of the critical genes in apoptosis signaling pathway (caspase 3 and caspase 9). Besides, the significant increase of intracellular [Ca2+] may also be an essential reason for the damage of mitochondria, eventually leading to apoptosis.

Klebsiella pneumoniae-OMVs activate death-signaling pathways in Human Bronchial Epithelial Host Cells (BEAS-2B)

The programmed cell death pathways of apoptosis are important in mammalian cellular protection from infections. The activation of these pathways depends on the presence of membrane receptors that bind bacterial components to activate the transduction mechanism. In addition to bacteria, these mechanisms can be activated by outer membrane vesicles (OMVs). OMVs are spherical vesicles of 20–250 nm diameter, constitutively released by Gram-negative bacteria. They contain several bacterial determinants including proteins, DNA/RNA and proteins, that activate different cellular processes in host cells. This study focused on Klebsiella pneumoniae-OMVs in activating death mechanisms in human bronchial epithelial cells (BEAS-2B). Characterization of purified OMVs was achieved by scanning electron microscopy, nanoparticle tracking analysis and protein profiling. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay while apoptotic induction was measured by flow cytometry and confirmed by western blotting. The OMVs produced showed a spherical morphology, with a diameter of 137.2 ± 41 nm and a vesicular density of 7.8 × 109 particles/mL Exposure of cell monolayers to 50 μg of K. pneumoniae-OMV for 14 h resulted in approximately 25 % cytotoxicity and 41.15–41.14 % of cells undergoing early and late apoptosis. Fluorescence microscopy revealed reduced cellular density, the presence of apoptotic bodies, chromatin condensation, and nuclear membrane blebbing in residual cells. Activation of caspases −3 and −9 and dysregulation of BAX, BIM and Bcl-xL indicated the activation of mitochondria-dependent apoptosis. Furthermore, a decrease in the antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase involved endoplasmic reticulum stress with the potential formation of reactive oxygen species. These findings provide evidence for the role of OMVs in apoptosis and involvement in the pathogenesis of K. pneumoniae infections.

Neurokinin-1 receptor antagonist aprepitant regulates autophagy and apoptosis via ROS/JNK in intrahepatic cholangiocarcinoma.

Intrahepatic cholangiocarcinoma (iCCA) has a poor prognosis and limited treatment options. Aprepitant, a selective NK-1R antagonist, can inhibit the growth of various tumours invitro and invivo. However, it remains unclear whether aprepitant has cytotoxic effects on iCCA. We measured the expression of SP/NK-1R in clinical samples of iCCA by immunohistochemistry. Then, we detected the cytotoxic effects of aprepitant on iCCA cells via MTT, EdU and colony formation assay. We constructed a subcutaneous xenograft model of BALB/c nude mice by using HCCC-9810 and RBE cell lines to explore the effects of aprepitant invivo. To elucidate the potential mechanisms, we explored the pro-apoptotic effect of aprepitant by flow cytometric, western blotting, ROS detection and JC-1 staining. Furthermore, we detected the autophagic level of HCCC-9810 and RBE by western blotting, mRFP-eGFP-LC3 adenovirus transfection and electron microscope. SP/NK-1R is significantly expressed in iCCA. Aprepitant inhibited human iCCA xenograft growth and dose-dependently decreased the viability of RBE and HCCC-9810 cells. Aprepitant-induced mitochondria-dependent apoptosis through ROS/JNK pathway. Additionally, pretreatment with z-VAD-fmk partly reversed the effect of aprepitant on cell viability, while NAC completely attenuated the cytotoxic effects of aprepitant invitro. Furthermore, we observed the dynamic changes of autophagosome in RBE and HCCC-9810 cells treated with aprepitant. SP/NK-1R signalling is significantly activated in iCCA and promotes the proliferation of iCCA cells. By contrast, aprepitant can induce autophagy and apoptosis in iCCA cells via ROS accumulation and subsequent activation of JNK.

Anti-Melanoma Effects of Miconazole: Investigating the Mitochondria Involvement.

Miconazole is an antimycotic drug showing anti-cancer effects in several cancers. However, little is known on its effects in melanoma. A375 and SK-MEL-28 human melanoma cell lines were exposed to miconazole and clotrimazole (up to 100 mM). Proliferation, viability with MTT assay and vascular mimicry were assayed at 24 h treatment. Molecular effects were measured at 6 h, namely, ATP-, ROS-release and mitochondria-related cytofluorescence. A metabolomic profile was also investigated at 6 h treatment. Carnitine was one of the most affected metabolites; therefore, the expression of 29 genes involved in carnitine metabolism was investigated in the public platform GEPIA2 on 461 melanoma patients and 558 controls. After 24 h treatments, miconazole and clotrimazole strongly and significantly inhibited proliferation in the presence of 10% serum on either melanoma cell lines; they also strongly reduced viability and vascular mimicry. After 6 h treatment, ATP reduction and ROS increase were observed, as well as a significant reduction in mitochondria-related fluorescence. Further, in A375, miconazole strongly and significantly altered expression of several metabolites including carnitines, phosphatidyl-cholines, all amino acids and several other small molecules, mostly metabolized in mitochondria. The expression of 12 genes involved in carnitine metabolism was found significantly modified in melanoma patients, 6 showing a significant impact on patients' survival. Finally, miconazole antiproliferation activity on A375 was found completely abrogated in the presence of carnitine, supporting a specific role of carnitine in melanoma protection toward miconazole effect, and was significantly reversed in the presence of caspases inhibitors such as ZVAD-FMK and Ac-DEVD-CHO, and a clear pro-apoptotic effect was observed in miconazole-treated cells, by FACS analysis of Annexin V-FITC stained cells. Miconazole strongly affects proliferation and other biological features in two human melanoma cell lines, as well as mitochondria-related functions such as ATP- and ROS-release, and the expression of several metabolites is largely dependent on mitochondria function. Miconazole, likely acting via carnitine and mitochondria-dependent apoptosis, is therefore suggested as a candidate for further investigations in melanoma treatments.

Abstract 4736: Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma

Abstract Oral squamous cell carcinoma (OSCC) is a prevalent form of cancer that develops in the oral cavity, globally recognized as the eighth most commonly diagnosed cancer. Despite the application of standard surgical techniques or concurrent chemoradiotherapy, the prognosis for OSCC patients remains unsatisfactory. Initially, cisplatin, the primary and most frequently used chemotherapy agent for treating OSCC, demonstrates effectiveness in therapy. Nonetheless, chemoresistance frequently arises, leading to treatment failure, and this is intricately associated with the activation of hypoxia-inducible factor 1α (HIF-1α) signaling. Recent research has brought to light heightened levels of HIF-1α-mediated vascular endothelial growth factor (VEGF) and BCL-2 in OSCC tumor sites, which play crucial roles in regulating angiogenesis and anti-apoptotic processes within cancer cells. Additionally, interventions aimed at targeting anti-apoptotic molecules or augmenting the expression of pro-apoptotic molecules may represent promising strategies to overcome chemoresistance in OSCC. Therefore, HIF-1α/VEGF/BCL-2 axis could be considered a potential target for the development of chemopreventive and chemotherapeutic strategies for OSCC. Lenvatinib is a targeted multi-kinase inhibitor that can inhibit tumor growth and angiogenesis by blocking the activation of vascular endothelial growth factor receptor (VEGFR) 1-3, fibroblast growth factor receptor (FGFR) 1-4, platelet-derived growth factor receptor (PDGFR) α, as well as the proto-oncogenes RET and KIT. However, whether lenvatinib may sensitizes OSCC to cisplatin remains unclear. In our study, we used the MTT assay to prove the cytotoxicity of OSCC cells (SAS and MOC1 cells) was induced by cisplatin and lenvatinib. We employed flow cytometry to verify that the combination of lenvatinib and cisplatin can indeed trigger both extrinsic and intrinsic apoptotic pathways in OSCC cells. Furthermore, our demonstration revealed that the induction of apoptosis pathways by the combination of lenvatinib and cisplatin is associated with mitochondrial-dependent apoptosis and death receptor-dependent apoptosis. Then, transwell invasion and migration assay results proved the inhibition effect of lenvatinib combined with cisplatin in SAS and MOC1 cells. Furthermore, we indicated that the combination of lenvatinib and cisplatin can effectively inhibit angiogenesis and anti-apoptotic mechanisms mediated by the HIF-1α/VEGF/BCL-2 axis in OSCC cells. In summary, our results demonstrate that the combined treatment with lenvatinib and cisplatin enhances the response of OSCC cells under hypoxic conditions. Additionally, it aims to mitigate the negative impact of hypoxia on cisplatin's therapeutic effectiveness and increase the sensitivity of OSCC cells to cisplatin. Citation Format: Ying-Tzu Chen, Yan-Ting Tsai, Fei-Ting Hsu, Hsi-Feng Tu. Evaluate the potential sensitization effect and underlying mechanism of lenvatinib on cisplatin resistance oral squamous cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4736.

HMGA1 regulates the mitochondrial apoptosis pathway in sepsis-induced cardiomyopathy.

High mobility group protein AT-hook 1 (HMGA1), an architectural transcription factor, has previously been reportedto play an essential role in architectural remodeling processes. However, its effects on cardiovascular diseases, particularly sepsis-induced cardiomyopathy, have remained unclear. The study aimed to investigate the role of HMGA1 in lipopolysaccharide-induced cardiomyopathy. Mice subjected to lipopolysaccharide for 12 h resulted in cardiac dysfunction. We used an adeno-associated virus 9 delivery system to achieve cardiac-specific expression of the HMGA1 gene in the mice. H9c2 cardiomyocytes were infected with Ad-HMGA1 to overexpress HMGA1 or transfected with si-HMGA1 to knock down HMGA1. Echocardiography was applied to measure cardiac function. RT-PCR was used to detect the transcriptional level of inflammatory cytokines. CD45 and CD68 immunohistochemical staining were used to detect inflammatory cell infiltration and TUNEL staining to evaluate the cardiomyocyte apoptosis, MitoSox was used to detect mitochondrial reactive oxygen species, JC-1 was used todetect Mitochondrial membrane potential. Our findings revealed that the overexpression of HMGA1 exacerbated myocardial inflammation and apoptosis in response to lipopolysaccharide treatment. Additionally, we also observed that H9c2 cardiomyocytes with HMGA1 overexpression exhibited enhanced inflammation and apoptosis upon stimulation with lipopolysaccharide for 12 h. Conversely, HMGA1 knockdown in H9c2 cardiomyocytes attenuated lipopolysaccharide-induced cardiomyocyte inflammation and apoptosis. Further investigations into the molecular mechanisms underlying these effects showed that HMGA1 promoted lipopolysaccharide-induced mitochondrial-dependent cardiomyocyte apoptosis. The study reveals that HMGA1 worsens myocardial inflammation and apoptosis in response to lipopolysaccharide treatment. Mechanically, HMGA1 exerts its effects by regulating the mitochondria-dependent apoptotic pathway.

The Protective Effects of Syringic Acid on Bisphenol A-Induced Neurotoxicity Possibly Through AMPK/PGC-1α/Fndc5 and CREB/BDNF Signaling Pathways.

Bisphenol A (BPA), an endocrine disruptor, is commonly used to produce epoxy resins and polycarbonate plastics. Continuous exposure to BPA may contribute to the development of diseases in humans and seriously affect their health. Previous research suggests a significant relationship between the increased incidence of neurological diseases and the level of BPA in the living environment. Syringic acid (SA), a natural derivative of gallic acid, has recently considered much attention due to neuromodulator activity and its anti-oxidant, anti-apoptotic, and anti-inflammatory effects. Therefore, in this study, we aimed to investigate the effects of SA on oxidative stress, apoptosis, memory and locomotor disorders, and mitochondrial function, and to identify the mechanisms related to Alzheimer's disease (AD) in the brain of rats receiving high doses of BPA. For this purpose, male Wistar rats received BPA (50, 100, and 200mg/kg) and SA (50mg/kg) for 21days. The results showed that BPA exposure significantly altered the rats' neurobehavioral responses. Additionally, BPA, by increasing the level of ROS, and MDA level, increased the level of oxidative stress while reducing the level of antioxidant enzymes, such as SOD, CAT, GPx, and mitochondrial GSH. The administration of BPA at 200mg/kg significantly decreased the expression of ERRα, TFAM, irisin, PGC-1α, Bcl-2, and FNDC5, while it increased the expression of TrkB, cytochrome C, caspase 3, and Bax. Moreover, the Western blotting results showed that BPA increased the levels of P-AMPK, GSK3b, p-tau, and Aβ, while it decreased the levels of PKA, P-PKA, Akt, BDNF, CREB, P-CREB, and PI3K. Meanwhile, SA at 50mg/kg reversed the behavioral, biochemical, and molecular changes induced by high doses of BPA. Overall, BPA could lead to the development of AD by affecting the mitochondria-dependent apoptosis pathway, as well as AMPK/PGC-1α/FNDC5 and CREB/BDNF/TrkB signaling pathways, and finally, by increasing the expression of tau and Aβ proteins. In conclusion, SA, as an antioxidant, significantly reduced the toxicity of BPA.

Involvement of DJ-1 in the pathogenesis of intervertebral disc degeneration via hexokinase 2-mediated mitophagy

Intervertebral disc degeneration (IDD) is an important pathological basis for degenerative spinal diseases and is involved in mitophagy dysfunction. However, the molecular mechanisms underlying mitophagy regulation in IDD remain unclear. This study aimed to clarify the role of DJ-1 in regulating mitophagy during IDD pathogenesis. Here, we showed that the mitochondrial localization of DJ-1 in nucleus pulposus cells (NPCs) first increased and then decreased in response to oxidative stress. Subsequently, loss- and gain-of-function experiments revealed that overexpression of DJ-1 in NPCs inhibited oxidative stress-induced mitochondrial dysfunction and mitochondria-dependent apoptosis, whereas knockdown of DJ-1 had the opposite effect. Mechanistically, mitochondrial translocation of DJ-1 promoted the recruitment of hexokinase 2 (HK2) to damaged mitochondria by activating Akt and subsequently Parkin-dependent mitophagy to inhibit oxidative stress-induced apoptosis in NPCs. However, silencing Parkin, reducing mitochondrial recruitment of HK2, or inhibiting Akt activation suppressed DJ-1-mediated mitophagy. Furthermore, overexpression of DJ-1 ameliorated IDD in rats through HK2-mediated mitophagy. Taken together, these findings indicate that DJ-1 promotes HK2-mediated mitophagy under oxidative stress conditions to inhibit mitochondria-dependent apoptosis in NPCs and could be a therapeutic target for IDD.

Betulinic acid induces apoptosis of HeLa cells via ROS-dependent ER stress and autophagy in vitro and in vivo.

Betulinic acid (BA), a naturally occurring lupane-type triterpenoid, possesses a wide range of potential activities against different types of cancer. However, the molecular mechanisms involved in anti-cervical cancer about BA were rarely investigated. Herein, the role of BA in cervical cancer suppression by ROS-mediated endoplasmic reticulum stress (ERS) and autophagy was deeply discussed. The findings revealed that BA activated Keap1/Nrf2 pathway and triggered mitochondria-dependent apoptosis due to ROS production. Furthermore, BA increased the intracellular Ca2+ levels, inhibited the expression of Beclin1 and promoted the expression of GRP78, LC3-II, and p62 associated with ERS and autophagy. Besides, BA initiated the formation of autophagosomes and inhibited autophagic flux by the co-administration of BA with 3-methyladenine (3-MA) and chloroquine (CQ), respectively. The in vivo experiment manifested that hydroxychloroquine (HCQ) enhanced the apoptosis induced by BA. For the first time, we demonstrated that BA could initiate early autophagy, inhibit autophagy flux, and induce protective autophagy in HeLa cells. Thus, BA could be a potential chemotherapy drug for cervical cancer, and inhibition of autophagy could enhance the anti-tumor effect of BA. However, the interactions of signaling factors between ERS-mediated and autophagy-mediated apoptosis deserve further attention.