RESUMEN
BACKGROUND AND AIMS: CircRNAs and autophagy are closely involved in the physiological and pathological processes of ovarian cancer; however, their exact mechanisms are still undetermined. This investigation aimed to elucidate the function and associated pathways of circFAM188A, which modulates proliferation, autophagy, and invasion in ovarian cancer (EOC). METHODS: The expression of circFAM188A in the tissues of EOC patients was assessed via RT-PCR. To elucidate proliferation, invasion, and autophagy in the tumor cells, Transwell, 5-ethynyl-2'-deoxyuridine (EdU), and mRFP-GFP-LC3 reporter assays were conducted. The binding sites between circ-FAM188A and the miR-670-3p, miR-670-3p and YY1 were predicted using bioinformatics and verified by dual-luciferase reporter assays. Pulldown assays demonstrated binding between ULK1 and circ-FAM188A. ULK1 was found to be crucial in the initial stage of autophagy. Moreover, an in vivo xenograft model was established by subcutaneous injection of nude mice with EOC cells. RESULT: Expression of circ-FAM188A was increased in EOC tissues relative to normal ovarian tissues and circ-FAM188A overexpression promoted proliferation, invasion, and autophagy; these effects were reversed by circ-FAM188A silencing. miR-670-3p and circ-FAM188A co-localized in the cytoplasm. circ-FAM188A enhanced YY1 expression by sponging miR-670-3p and was also shown to interact with ULK1. CONCLUSION: It is thus suggested that circ-FAM188A modulates autophagy by sponging miR-670-3p as well as interacting with ULK1.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Carcinoma Epitelial de Ovario , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Péptidos y Proteínas de Señalización Intracelular , Ratones Desnudos , MicroARNs , Neoplasias Ováricas , ARN Circular , Humanos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Femenino , MicroARNs/genética , Autofagia/genética , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/patología , Carcinoma Epitelial de Ovario/metabolismo , Animales , Ratones , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Neoplasias Ováricas/metabolismo , Proliferación Celular/genética , ARN Circular/genética , ARN Circular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Línea Celular Tumoral , Factor de Transcripción YY1/genética , Factor de Transcripción YY1/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Movimiento Celular/genética , Persona de Mediana EdadRESUMEN
BACKGROUND: High expression of ubiquitin ligase MDM2 is a primary cause of p53 inactivation in many tumors, making it a promising therapeutic target. However, MDM2 inhibitors have failed in clinical trials due to p53-induced feedback that enhances MDM2 expression. This underscores the urgent need to find an effective adaptive genotype or combination of targets. METHODS: Kinome-wide CRISPR/Cas9 knockout screen was performed to identify genes that modulate the response to MDM2 inhibitor using TP53 wild type cancer cells and found ULK1 as a candidate. The MTT cell viability assay, flow cytometry and LDH assay were conducted to evaluate the activation of pyroptosis and the synthetic lethality effects of combining ULK1 depletion with p53 activation. Dual-luciferase reporter assay and ChIP-qPCR were performed to confirm that p53 directly mediates the transcription of GSDME and to identify the binding region of p53 in the promoter of GSDME. ULK1 knockout / overexpression cells were constructed to investigate the functional role of ULK1 both in vitro and in vivo. The mechanism of ULK1 depletion to activate GSMDE was mainly investigated by qPCR, western blot and ELISA. RESULTS: By using high-throughput screening, we identified ULK1 as a synthetic lethal gene for the MDM2 inhibitor APG115. It was determined that deletion of ULK1 significantly increased the sensitivity, with cells undergoing typical pyroptosis. Mechanistically, p53 promote pyroptosis initiation by directly mediating GSDME transcription that induce basal-level pyroptosis. Moreover, ULK1 depletion reduces mitophagy, resulting in the accumulation of damaged mitochondria and subsequent increasing of reactive oxygen species (ROS). This in turn cleaves and activates GSDME via the NLRP3-Caspase inflammatory signaling axis. The molecular cascade makes ULK1 act as a crucial regulator of pyroptosis initiation mediated by p53 activation cells. Besides, mitophagy is enhanced in platinum-resistant tumors, and ULK1 depletion/p53 activation has a synergistic lethal effect on these tumors, inducing pyroptosis through GSDME directly. CONCLUSION: Our research demonstrates that ULK1 deficiency can synergize with MDM2 inhibitors to induce pyroptosis. p53 plays a direct role in activating GSDME transcription, while ULK1 deficiency triggers upregulation of the ROS-NLRP3 signaling pathway, leading to GSDME cleavage and activation. These findings underscore the pivotal role of p53 in determining pyroptosis and provide new avenues for the clinical application of p53 restoration therapies, as well as suggesting potential combination strategies.
Asunto(s)
Homólogo de la Proteína 1 Relacionada con la Autofagia , Piroptosis , Especies Reactivas de Oxígeno , Transducción de Señal , Proteína p53 Supresora de Tumor , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Ratones , Especies Reactivas de Oxígeno/metabolismo , Animales , Regulación hacia Arriba , Mutaciones Letales Sintéticas , Femenino , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Línea Celular Tumoral , Proteína con Dominio Pirina 3 de la Familia NLRRESUMEN
Perioperative neurocognitive disorders (PND) are intractable, indistinct, and considerably diminish the postoperative quality of life of patients. It has been proved that Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) was involved in neurodegenerative diseases by regulating mitochondrial biogenesis. The underlying mechanisms of PGC-1α and Nod-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome in PND are not well understood. In this study, we constructed a model of laparotomy in aged mice, and then examined the cognition changes with novel object recognition tests and fear condition tests. The protein levels of PGC-1α and NLRP3 in the hippocampus were detect after surgery. Our results showed that NLRP3 and downstream PI3K/AKT pathway expressions were augmented in the hippocampus after surgery, whereas, the expressions of PGC-1α/estrogen-related receptor α (ERRα)/Unc-51-like autophagy activating kinase 1 (ULK1) pathway were diminished after surgery. In addition, we found that NLRP3 was mainly co-localized with neurons in the hippocampus, and synaptic-related proteins were reduced after surgery. At the same time, transmission electron microscopy (TEM) showed that mitochondria were impaired after surgery. Pharmacological treatment of MCC950, a selective NLRP3 inhibitor, effectively alleviated PND. Activation of PGC-1α with ZLN005 significantly ameliorated PND by enhancing the PGC-1α/ERRα/ULK1 signaling pathway, and further suppressing NLRP3 activation. As a result, we conclude that suppression of the PGC-1α/ERRα/ULK1 signaling pathway is the primary mechanism of PND which caused mitochondrial dysfunction, and activated NLRP3 inflammasome and downstream PI3K/AKT pathway, eventually improved cognitive dysfunction.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Hipocampo , Inflamasomas , Ratones Endogámicos C57BL , Mitocondrias , Proteína con Dominio Pirina 3 de la Familia NLR , Trastornos Neurocognitivos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Receptores de Estrógenos , Transducción de Señal , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Inflamasomas/metabolismo , Ratones , Transducción de Señal/fisiología , Transducción de Señal/efectos de los fármacos , Hipocampo/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Mitocondrias/metabolismo , Masculino , Receptores de Estrógenos/metabolismo , Trastornos Neurocognitivos/metabolismo , Trastornos Neurocognitivos/etiología , Envejecimiento/metabolismo , Laparotomía/efectos adversos , Sulfonamidas/farmacología , Furanos , IndenosRESUMEN
Mutational activation of KRAS occurs commonly in lung carcinogenesis and, with the recent U.S. Food and Drug Administration approval of covalent inhibitors of KRASG12C such as sotorasib or adagrasib, KRAS oncoproteins are important pharmacological targets in non-small cell lung cancer (NSCLC). However, not all KRASG12C-driven NSCLCs respond to these inhibitors, and the emergence of drug resistance in those patients who do respond can be rapid and pleiotropic. Hence, based on a backbone of covalent inhibition of KRASG12C, efforts are underway to develop effective combination therapies. Here, we report that the inhibition of KRASG12C signaling increases autophagy in KRASG12C-expressing lung cancer cells. Moreover, the combination of DCC-3116, a selective ULK1/2 inhibitor, plus sotorasib displays cooperative/synergistic suppression of human KRASG12C-driven lung cancer cell proliferation in vitro and superior tumor control in vivo. Additionally, in genetically engineered mouse models of KRASG12C-driven NSCLC, inhibition of either KRASG12C or ULK1/2 decreases tumor burden and increases mouse survival. Consequently, these data suggest that ULK1/2-mediated autophagy is a pharmacologically actionable cytoprotective stress response to inhibition of KRASG12C in lung cancer.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Proliferación Celular , Péptidos y Proteínas de Señalización Intracelular , Neoplasias Pulmonares , Proteínas Proto-Oncogénicas p21(ras) , Animales , Femenino , Humanos , Masculino , Ratones , Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/metabolismo , Piperazinas , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas p21(ras)/genética , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Piridinas , Pirimidinas/farmacologíaRESUMEN
The five-year survival rate for patients with hepatocellular carcinoma (HCC) is only 20â¯%, highlighting the urgent need to identify new therapeutic targets and develop potential therapeutic options to improve patient prognosis. One promising approach is inhibiting autophagy as a strategy for HCC treatment. In this study, we established a virtual docking conformation of the autophagy promoter ULK1 binding XST-14 derivatives. Based on this conformation, we designed and synthesized four series of derivatives. By evaluating their affinity and anti-HCC effects, we confirmed that these compounds exert anti-HCC activity by inhibiting ULK1. The structure-activity relationship was summarized, with derivative A4 showing 10 times higher activity than XST-14 and superior efficacy to sorafenib against HCC. A4 has excellent effect on reducing tumor growth and enhancing sorafenib activity in HepG2 and HCCLM3 cells. Moreover, we verified the therapeutic effect of A4 in sorafenib-resistant HCC cells both in vivo and in vitro. These results suggest that inhibiting ULK1 to regulate autophagy may become a new treatment method for HCC and that A4 will be used as a lead drug for HCC in further research. Overall, A4 shows good drug safety and efficacy, offering hope for prolonging the survival of HCC patients.
Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Diseño de Fármacos , Indoles , Neoplasias Hepáticas , Inhibidores de Proteínas Quinasas , Sorafenib , Animales , Humanos , Ratones , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Autofagia/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/antagonistas & inhibidores , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Células Hep G2 , Indoles/farmacología , Indoles/química , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Ratones Endogámicos BALB C , Ratones Desnudos , Simulación del Acoplamiento Molecular , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/síntesis química , Sorafenib/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Ischemia reperfusion (IR) causes impaired myocardial function, and autophagy activation ameliorates myocardial IR injury. Isoliquiritigenin (ISO) has been found to protect myocardial tissues via AMPK, with exerting anti-tumor property through autophagy activation. This study aims to investigate ISO capacity to attenuate myocardial IR through autophagy activation mediated by AMPK/mTOR/ULK1 signaling. METHODS: ISO effects were explored by SD rats and H9c2 cells. IR rats and IR-induced H9c2 cell models were established by ligating left anterior descending (LAD) coronary artery and hypoxia/re-oxygenation, respectively, followed by low, medium and high dosages of ISO intervention (Rats: 10, 20, and 40 mg/kg; H9c2 cells: 1, 10, and 100 µmol/L). Myocardial tissue injury in rats was assessed by myocardial function-related index, HE staining, Masson trichrome staining, TTC staining, and ELISA. Autophagy of H9c2 cells was detected by transmission electron microscopy (TEM) and immunofluorescence. Autophagy-related and AMPK/mTOR/ULK1 pathway-related protein expressions were detected with western blot. RESULTS: ISO treatment caused myocardial function improvement, and inhibition of myocardial inflammatory infiltration, fibrosis, infarct area, oxidative stress, CK-MB, cTnI, and cTnT expression in IR rats. In IR-modeled H9c2 cells, ISO treatment lowered apoptosis rate and activated autophagy and LC3 fluorescence expression. In vivo and in vitro, ISO intervention exhibited enhanced Beclin1, LC3II/LC3I, and p-AMPK/AMPK levels, whereas inhibited P62, p-mTOR/mTOR and p-ULK1(S757)/ULK1 protein expression, activating autophagy and protecting myocardial tissues from IR injury. CONCLUSION: ISO treatment may induce autophagy by regulating AMPK/mTOR/ULK1 signaling, thereby improving myocardial IR injury, as a potential candidate for treatment of myocardial IR injury.
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Proteínas Quinasas Activadas por AMP , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Chalconas , Daño por Reperfusión Miocárdica , Miocitos Cardíacos , Ratas Sprague-Dawley , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , Masculino , Ratas , Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Línea Celular , Chalconas/farmacología , Modelos Animales de Enfermedad , Fibrosis , Infarto del Miocardio/patología , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/metabolismo , Infarto del Miocardio/fisiopatología , Infarto del Miocardio/enzimología , Daño por Reperfusión Miocárdica/patología , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Daño por Reperfusión Miocárdica/fisiopatología , Daño por Reperfusión Miocárdica/enzimología , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Miocitos Cardíacos/enzimología , Miocitos Cardíacos/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
Distal hereditary motor neuropathy (dHMN) is a progressive neurological disease characterized by distal limb muscle weakness and amyotrophy. Sigma 1 receptor (σ1R), a gene product of SIGMAR1, mutations have been reported to induce dHMN, but its mechanism remains unknown. This study aims to explore the effect of C238T and 31_50del mutations in σ1R on neuronal SH-SY5Y cell functions. The SH-SY5Y cells that overexpressed σ1R, C238T mutant σ1R (σ1RC238T) or 31_50del mutant σ1R (σ1R31_50del) were constructed by pEGFPN1 vectors. We used Western blot (WB) and immunofluorescence (IF) staining to detect the expression of σ1R and green fluorescent proteins (GFP). Then, we evaluated the impact of σ1R mutation on apoptosis, autophagy, endoplasmic reticulum stress, and the involvement of the unfolded protein response (UPR) pathway in SH-SY5Y cells. We found that σ1RC238T and σ1R31_50del downregulated σ1R and promoted the apoptosis of SH-SY5Y cells. σ1RC238T and σ1R31_50del increased p-PERK, p-eIF2α, p-JNK, BIP, ATF4, CHOP, ATF6, XBP1, Caspase3, Caspase12 expressions and Ca2+ concentration, whereas decreased ATP content in SH-SY5Y cells. Besides, the expressions of LC3B, Lamp1, ATG7, Beclin-1 and phosphorylation of AMPK and ULK1 were increased, while the p62 level decreased after C238T or 31_50del mutation of σ1R. Additionally, AMPK knockdown abolished the apoptosis mediated by σ1RC238T or σ1R31_50del in SH-SY5Y cells. Our results indicated that C238T or 31_50del mutation in σ1R promoted motor neuron apoptosis through the AMPK/ULK1 pathway in dHMN. This study shed light on a better understanding of the neurons pathological mechanisms mediated by σ1R C238T and σ1R 31-50del in dHMN.
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Apoptosis , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Estrés del Retículo Endoplásmico , Receptores sigma , Receptor Sigma-1 , Humanos , Receptores sigma/metabolismo , Receptores sigma/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Línea Celular Tumoral , Transducción de Señal , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Respuesta de Proteína Desplegada , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , MutaciónRESUMEN
One of the key events in autophagy is the formation of a double-membrane phagophore, and many regulatory mechanisms underpinning this remain under investigation. WIPI2b is among the first proteins to be recruited to the phagophore and is essential for stimulating autophagy flux by recruiting the ATG12-ATG5-ATG16L1 complex, driving LC3 and GABARAP lipidation. Here, we set out to investigate how WIPI2b function is regulated by phosphorylation. We studied two phosphorylation sites on WIPI2b, S68 and S284. Phosphorylation at these sites plays distinct roles, regulating WIPI2b's association with ATG16L1 and the phagophore, respectively. We confirm WIPI2b is a novel ULK1 substrate, validated by the detection of endogenous phosphorylation at S284. Notably, S284 is situated within an 18-amino acid stretch, which, when in contact with liposomes, forms an amphipathic helix. Phosphorylation at S284 disrupts the formation of the amphipathic helix, hindering the association of WIPI2b with membranes and autophagosome formation. Understanding these intricacies in the regulatory mechanisms governing WIPI2b's association with its interacting partners and membranes, holds the potential to shed light on these complex processes, integral to phagophore biogenesis.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Proteínas Relacionadas con la Autofagia , Autofagia , Proteínas de la Membrana , Unión Proteica , Fosforilación , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas Relacionadas con la Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Humanos , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Autofagosomas/metabolismo , Proteínas Portadoras/metabolismo , Células HEK293 , Proteínas Asociadas a Microtúbulos/metabolismoRESUMEN
OBJECTIVE: Reduced adiponectin (ADPN) levels have been implicated in the pathogenesis of prostate cancer (PCa). The role of glycolysis in cancer development and treatment has attracted increasing attention. The present study aimed to elucidate its impact on PCa and to explore the mechanistic involvement of glycolysis. METHODS: An RM-1 cell xenograft model of Adpn-knockout mice was used to corroborate the effects of glycolysis, AMP-activated protein kinase (AMPK) signaling, and autophagy on tumor xenograft progression. The effect of ADPN on PCa cells was evaluated using the Cell Counting Kit-8 (CCK-8), lactate levels, and flow cytometry. The expression of glycolysis-related genes was detected using real-time RT-PCR in LNCaP and PC-3 cells after incubation with ADPN. Autophagic flux after ADPN treatment was quantified by chloroquine intervention and confocal analysis of mRFP-GFP-LC3. Alterations in the levels of adiponectin receptor 1 (AdipoR1), AMPK, Unc-51-like kinase 1 (ULK1), autophagy-related protein 7 (ATG7), p62, and microtubule-associated protein 1 light chain 3 beta (LC3B) were assessed after incubation of LNCaP cells with ADPN. RESULTS: Proteomic analysis of xenograft tumors demonstrated significant upregulation of glycolysis in Adpn-/- mice. Lower levels of ADPN accelerated tumor xenograft growth, diminished p-AMPKα/AMPKα ratio and LC3B II/I ratio, and elevated levels of proliferating cell nuclear antigen (PCNA) within the tumor microenvironment. ADPN inhibited proliferation and glycolysis and potentiated apoptosis in both cell lines. Expression of glycolysis-related genes decreased after ADPN treatment. Autophagic flux was elevated, as evidenced by changes in autophagy-related proteins and confocal microscopy analysis of mRFP-GFP-LC3. It led to the suppression of p62 while inducing phosphorylation of AMPKα and upregulating AdipoR1, ULK1, ATG7, and LC3B II/I ratio. CONCLUSION: ADPN inhibited the proliferation and progression of PCa cell-derived tumor xenografts by inhibiting glycolysis. Specifically, ADPN effectively inhibits glycolysis and activates the downstream AMPK/ULK1 signaling pathway to suppress proliferation of PCa cells.
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Proteínas Quinasas Activadas por AMP , Adiponectina , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Glucólisis , Ratones Noqueados , Neoplasias de la Próstata , Transducción de Señal , Masculino , Animales , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/genética , Glucólisis/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Humanos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Adiponectina/metabolismo , Adiponectina/genética , Línea Celular Tumoral , Autofagia/efectos de los fármacos , Ratones , Proliferación Celular/efectos de los fármacos , Receptores de Adiponectina/metabolismo , Receptores de Adiponectina/genéticaRESUMEN
BACKGROUND: Left ventricular diastolic dysfunction (LVDD) is a manifestation of heart failure, with both its incidence and prevalence increasing annually. Currently, no pharmacological treatments are available for LVDD, highlighting the urgent need for new therapeutic discoveries. Ginsenosides are commonly used in cardiovascular therapy. Previous research has synthesized the ginsenoside precursor molecule, 20S-O-Glc-DM (C20DM), through biosynthesis. C20DM shows greater bioavailability, eco-friendliness, and cost-effectiveness compared to traditional ginsenosides, positioning it as a promising option for treating LVDD. PURPOSE: This study firstly documents the therapeutic activity of C20DM against LVDD and unveils its potential mechanisms of action. It provides a pharmacological basis for C20DM as a new cardiovascular therapeutic agent. METHODS: In this study, models of LVDD in mice and ISO-induced H9C2 cell damage were developed. Cell viability, ROS and Ca2+ levels, mitochondrial membrane potential, and proteins associated with mitochondrial biogenesis and autophagy were evaluated in the in vitro experiments. Animal experiments involved administering medication for 3 weeks to validate the therapeutic effects of C20DM and its impact on mitochondria and autophagy. RESULTS: Research has shown that C20DM is more effective than Metoprolol in treating LVDD, significantly lowering the E/A ratio, e'/a' ratio, and IVRT, and ameliorating myocardial inflammation and fibrosis. C20DM influences the activity of PGC-1α, downregulates PINK1 and Parkin, thereby enhancing mitochondrial quality control, and restoring mitochondrial oxidative respiration and membrane potential. Furthermore, C20DM reduces excessive autophagy in cardiomyocytes via the AMPK-mTOR-ULK1 pathway, diminishing cardiomyocyte hypertrophy and damage. CONCLUSIONS: Overall, our research indicates that C20DM has the potential to enhance LVDD through the regulation of mitochondrial quality control and cellular autophagy, making it a promising option for heart failure therapy.
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Autofagia , Ginsenósidos , Potencial de la Membrana Mitocondrial , Miocitos Cardíacos , Disfunción Ventricular Izquierda , Animales , Autofagia/efectos de los fármacos , Miocitos Cardíacos/efectos de los fármacos , Disfunción Ventricular Izquierda/tratamiento farmacológico , Ratones , Ginsenósidos/farmacología , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos C57BL , Línea Celular , Especies Reactivas de Oxígeno/metabolismo , Modelos Animales de Enfermedad , Ratas , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Supervivencia Celular/efectos de los fármacos , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Mitocondrias/efectos de los fármacos , Proteínas Quinasas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Calcio/metabolismoRESUMEN
Autophagy is a highly conserved process from yeast to mammals in which intracellular materials are engulfed by a double-membrane organelle called autophagosome and degrading materials by fusing with the lysosome. The process of autophagy is regulated by sequential recruitment and function of autophagy-related (Atg) proteins. Genetic hierarchical analyses show that the ULK1 complex comprised of ULK1-FIP200-ATG13-ATG101 translocating from the cytosol to autophagosome formation sites as a most upstream ATG factor; this translocation is critical in autophagy initiation. However, how this translocation occurs remains unclear. Here, we show that ULK1 is palmitoylated by palmitoyltransferase ZDHHC13 and translocated to the autophagosome formation site upon autophagy induction. We find that the ULK1 palmitoylation is required for autophagy initiation. Moreover, the ULK1 palmitoylated enhances the phosphorylation of ATG14L, which is required for activating PI3-Kinase and producing phosphatidylinositol 3-phosphate, one of the autophagosome membrane's lipids. Our results reveal how the most upstream ULK1 complex translocates to the autophagosome formation sites during autophagy.
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Aciltransferasas , Autofagosomas , Homólogo de la Proteína 1 Relacionada con la Autofagia , Proteínas Relacionadas con la Autofagia , Autofagia , Péptidos y Proteínas de Señalización Intracelular , Lipoilación , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Autofagia/fisiología , Humanos , Proteínas Relacionadas con la Autofagia/metabolismo , Proteínas Relacionadas con la Autofagia/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Fosforilación , Aciltransferasas/metabolismo , Aciltransferasas/genética , Autofagosomas/metabolismo , Células HEK293 , Fosfatos de Fosfatidilinositol/metabolismo , Animales , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Proteínas Adaptadoras del Transporte Vesicular/genética , Transporte de Proteínas , Proteínas de Transporte VesicularRESUMEN
Here, we presented the study of the molecular mechanisms underlying the action of Wulingsan (WLS) in rats with metabolic-associated fatty liver disease (MAFLD) induced by a high-fat diet (HFD). High-performance liquid chromatography was employed to identify the chemical components of WLS. After 2 weeks of HFD induction, MAFLD rats were treated with WLS in three different doses for 6 weeks, a positive control treatment or with a vehicle. Lipid metabolism, liver function, oxidative stress, and inflammatory factors as well as pathomorphological changes in liver parenchyma were assessed in all groups. Finally, the expressions of autophagy-related markers, adenosine monophosphate-activated protein kinase (AMPK)/mechanistic target of rapamycin (mTOR)/unc-51-like kinase-1 (ULK1) signaling pathway-related genes, and proteins in liver were detected. The results revealed that WLS significantly ameliorated liver injury, the dysfunction of the lipid metabolism, the oxidative stress, and overall inflammatory status. Furthermore, WLS increased the expressions of LC3B-II, Beclin1, p-AMPK, and ULK1, along with decreased p62, p-mTOR, and sterol regulatory element-binding protein-1c levels. In conclusion, we showed that WLS is capable of alleviating HFD-induced MAFLD by improving lipid accumulation, suppressing oxidative stress and inflammation, and promoting autophagy.
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Proteínas Quinasas Activadas por AMP , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Dieta Alta en Grasa , Metabolismo de los Lípidos , Estrés Oxidativo , Transducción de Señal , Serina-Treonina Quinasas TOR , Animales , Autofagia/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Serina-Treonina Quinasas TOR/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Ratas , Dieta Alta en Grasa/efectos adversos , Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Ratas Sprague-Dawley , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Modelos Animales de EnfermedadRESUMEN
Aim: Chromones are promising for anticancer drug development.Methods & results: 12 chromone-based compounds were synthesized and tested against cancer cell lines. Compound 8 showed the highest cytotoxicity (LC50 3.2 µM) against colorectal cancer cells, surpassing 5-fluorouracil (LC50 4.2 µM). It suppressed colony formation, induced cell cycle arrest and triggered apoptotic cell death, confirmed by staining and apoptosis markers. Cell death was accompanied by enhanced reactive oxygen species formation and modulation of the autophagic machinery (autophagy marker light chain 3B (LC3B); adenosine monophosphate-activated protein kinase (AMPK); protein kinase B (PKB); UNC-51-like kinase (ULK)-1; and ULK2). Molecular docking and dynamic simulations revealed that compound 8 directly binds to ULK1.Conclusion: Compound 8 is a promising lead for autophagy-modulating anti-colon cancer drugs.
[Box: see text].
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Antineoplásicos , Apoptosis , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Cromonas , Neoplasias del Colon , Simulación del Acoplamiento Molecular , Humanos , Homólogo de la Proteína 1 Relacionada con la Autofagia/antagonistas & inhibidores , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Autofagia/efectos de los fármacos , Apoptosis/efectos de los fármacos , Cromonas/farmacología , Cromonas/química , Cromonas/síntesis química , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Neoplasias del Colon/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Proliferación Celular/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Línea Celular Tumoral , Relación Estructura-Actividad , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Especies Reactivas de Oxígeno/metabolismoRESUMEN
Background: Ovarian cancer is an aggressive malignancy with high mortality known for its considerable metastatic potential. This study aimed to explore the expression and functional role of Unc-51 like autophagy activating kinase 2 (ULK2) in the progression of ovarian cancer. Methods: ULK2 expression patterns in ovarian cancer tissues as well as benign tumor control samples obtained from our institution were evaluated using immunohistochemistry. Cell counting kit 8 and Transwell assays were applied to assess the effects of ULK2 overexpression on cell proliferation, migration and invasion, respectively. RNA sequencing was performed to explore potential mechanisms of action of ULK2 beyond its classical autophagy modulation. Results: Our experiments showed significant downregulation of ULK2 in ovarian cancer tissues. Importantly, low expression of ULK2 was markedly correlated with decreased overall survival. In vitro functional studies further demonstrated that overexpression of ULK2 significantly suppressed tumor cell proliferation, migration, and invasion. RNA sequencing analysis revealed a potential regulatory role of ULK2 in the insulin signaling pathway through upregulation of insulin-like growth factor binding protein-3 (IGFBP3) in ovarian cancer cells. Conclusions: In summary, the collective data indicated that ULK2 acted as a tumor suppressor in ovarian cancer by upregulating the expression of IGFBP3. Our study underscores the potential utility of ULK2 as a valuable prognostic marker for ovarian cancer.
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Movimiento Celular , Proliferación Celular , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Invasividad Neoplásica , Neoplasias Ováricas , Humanos , Femenino , Movimiento Celular/genética , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/mortalidad , Línea Celular Tumoral , Invasividad Neoplásica/genética , Proliferación Celular/genética , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Regulación Neoplásica de la Expresión Génica , Regulación hacia Arriba , Transducción de Señal , Proteínas Serina-Treonina QuinasasRESUMEN
Autophagy is essential for the adaptive response to exercise and physiological skeletal muscle functionality. However, the mechanisms leading to the activation of macroautophagy and chaperone-mediated autophagy in human skeletal muscle in response to high-intensity exercise remain elusive. Our findings demonstrate that macroautophagy and chaperone-mediated autophagy are stimulated by high-intensity exercise in normoxia (PIO2: 143 mmHg) and severe acute hypoxia (PIO2: 73 mmHg) in healthy humans. High-intensity exercise induces macroautophagy initiation through AMPKα phosphorylation, which phosphorylates and activates ULK1. ULK1 phosphorylates BECN1 at Ser15, eliciting the dissociation of BECN1-BCL2 crucial for phagophore formation. Besides, high-intensity exercise elevates the LC3B-II:LC3B-I ratio, reduces total SQSTM1/p62 levels, and induces p-Ser349 SQSTM1/p62 phosphorylation, suggesting heightened autophagosome degradation. PHAF1/MYTHO, a novel macroautophagy biomarker, is highly upregulated in response to high-intensity exercise. The latter is accompanied by elevated LAMP2A expression, indicating chaperone-mediated autophagy activation regardless of post-exercise HSPA8/HSC70 downregulation. Despite increased glycolytic metabolism, severe acute hypoxia does not exacerbate the autophagy signaling response. Signaling changes revert within 1 min of recovery with free circulation, while the application of immediate post-exercise ischemia impedes recovery. Our study concludes that macroautophagy and chaperone-mediated autophagy pathways are strongly activated by high-intensity exercise, regardless of PO2, and that oxygenation is necessary to revert these signals to pre-exercise values. PHAF1/MYTHO emerges as a pivotal exercise-responsive autophagy marker positively associated with the LC3B-II:LC3B-I ratio.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Beclina-1 , Autofagia Mediada por Chaperones , Ejercicio Físico , Hipoxia , Músculo Esquelético , Humanos , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Ejercicio Físico/fisiología , Masculino , Fosforilación , Hipoxia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Beclina-1/metabolismo , Beclina-1/genética , Autofagia Mediada por Chaperones/genética , Isquemia/metabolismo , Isquemia/patología , Proteína Sequestosoma-1/metabolismo , Proteína Sequestosoma-1/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Adulto , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteína 2 de la Membrana Asociada a los Lisosomas/metabolismo , Proteína 2 de la Membrana Asociada a los Lisosomas/genética , Proteínas del Choque Térmico HSC70/metabolismo , Proteínas del Choque Térmico HSC70/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , FemeninoRESUMEN
INTRODUCTION: Hyperglycemia-induced endothelial cell injury is one of the main causes of diabetic vasculopathy. Fat mass and obesity-associated protein (FTO) was the first RNA N6-methyladenosine (m6A) demethylase identified; it participates in the pathogenesis of diabetes. However, the role of FTO in hyperglycemia-induced vascular endothelial cell injury remains unclear. MATERIALS AND METHODS: The effects of FTO on cellular m6A, autophagy, oxidative stress, proliferation, and cytotoxicity were explored in human umbilical vein endothelial cells (HUVECs) treated with high glucose (33.3 mmol/mL) after overexpression or pharmacological inhibition of FTO. MeRIP-qPCR and RNA stability assays were used to explore the molecular mechanisms by which FTO regulates autophagy. RESULTS: High glucose treatment increased m6A levels and reduced FTO protein expression in HUVECs. Wild-type overexpression of FTO markedly inhibited reactive oxygen species generation by promoting autophagy, increasing endothelial cell proliferation, and decreasing the cytotoxicity of high glucose concentrations. The pharmacological inhibition of FTO showed the opposite results. Mechanistically, we identified Unc-51-like kinase 1 (ULK1), a gene responsible for autophagosome formation, as a downstream target of FTO-mediated m6A modification. FTO overexpression demethylated ULK1 mRNA and inhibited its degradation in an m6A-YTHDF2-dependent manner, leading to autophagy activation. CONCLUSIONS: Our study demonstrates the functional importance of FTO-mediated m6A modification in alleviating endothelial cell injury under high glucose conditions and indicates that FTO may be a novel therapeutic target for diabetic vascular complications.
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Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Hiperglucemia , Especies Reactivas de Oxígeno , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/metabolismo , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Autofagia/efectos de los fármacos , Autofagia/fisiología , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Angiopatías Diabéticas/metabolismo , Angiopatías Diabéticas/genética , Angiopatías Diabéticas/patología , Glucosa/farmacología , Glucosa/metabolismo , Células Endoteliales de la Vena Umbilical Humana/efectos de los fármacos , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Hiperglucemia/metabolismo , Péptidos y Proteínas de Señalización Intracelular , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismoRESUMEN
OBJECTIVE: Studies have demonstrated that cycloastragenol induces antitumor effects in prostate, colorectal and gastric cancers; however, its efficacy for inhibiting the proliferation of lung cancer cells is largely unexplored. This study explores the efficacy of cycloastragenol for inhibiting non-small cell lung cancer (NSCLC) and elucidates the underlying molecular mechanisms. METHODS: The effects of cycloastragenol on lung cancer cell proliferation were assessed using an adenosine triphosphate monitoring system based on firefly luciferase and clonogenic formation assays. Cycloastragenol-induced apoptosis in lung cancer cells was evaluated using dual staining flow cytometry with an annexin V-fluorescein isothiocyanate/propidium iodide kit. To elucidate the role of cycloastragenol in the induction of apoptosis, apoptosis-related proteins were examined using Western blots. Immunofluorescence and Western blotting were used to determine whether cycloastragenol could induce autophagy in lung cancer cells. Genetic techniques, including small interfering RNA technology, were used to investigate the underlying mechanisms. The effects against lung cancer and biosafety of cycloastragenol were evaluated using a mouse subcutaneous tumor model. RESULTS: Cycloastragenol triggered both autophagy and apoptosis. Specifically, cycloastragenol promoted apoptosis by facilitating the accumulation of phorbol-12-myristate-13-acetate-induced protein 1 (NOXA), a critical apoptosis-related protein. Moreover, cycloastragenol induced a protective autophagy response through modulation of the adenosine 5'-monophosphate-activated protein kinase (AMPK)/unc-51-like autophagy-activating kinase (ULK1)/mammalian target of rapamycin (mTOR) pathway. CONCLUSION: Our study sheds new light on the antitumor efficacy and mechanism of action of cycloastragenol in NSCLC. This insight provides a scientific basis for exploring combination therapies that use cycloastragenol and inhibiting the AMPK/ULK1/mTOR pathway as a promising approach to combating lung cancer. Please cite this article as follows: Zhu LH, Liang YP, Yang L, Zhu F, Jia LJ, Li HG. Cycloastragenolinduces apoptosis and protective autophagy through AMPK/ULK1/mTOR axis in human non-small celllung cancer cell lines. J Integr Med. 2024; 22(4): 504-515.
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Proteínas Quinasas Activadas por AMP , Apoptosis , Homólogo de la Proteína 1 Relacionada con la Autofagia , Autofagia , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Serina-Treonina Quinasas TOR , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Serina-Treonina Quinasas TOR/metabolismo , Apoptosis/efectos de los fármacos , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Animales , Autofagia/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Ratones Desnudos , Ratones Endogámicos BALB C , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genéticaRESUMEN
Endurance exercise training improves exercise capacity as well as skeletal muscle and whole body metabolism, which are hallmarks of high quality-of-life and healthy aging. However, its mechanisms are not yet fully understood. Exercise-induced mitophagy has emerged as an important step in mitochondrial remodeling. Unc-51-like autophagy-activating kinase 1, ULK1, specifically its activation by phosphorylation at serine 555, was discovered as an autophagy driver and to be important for energetic stress-induced mitophagy in skeletal muscle, making it a potential mediator of the beneficial effects of exercise on mitochondrial remodeling. Here, we used CRISPR/Cas9-mediated gene editing and generated knock-in mice with a serine-to-alanine mutation of Ulk1 on serine 555. We now report that these mice displayed normal endurance capacity and cardiac function at baseline with a mild impairment in energy metabolism as indicated by an accelerated increase of respiratory exchange ratio (RER) during acute exercise stress; however, this was completely corrected by 8 wk of voluntary running. Ulk1-S555A mice also retained the exercise-mediated improvements in exercise capacity and metabolic flux. We conclude that Ulk1 phosphorylation at S555 is not required for exercise-mediated improvements of exercise and metabolic capacity in healthy mice.NEW & NOTEWORTHY We have used CRISPR/Cas9-mediated gene editing to generate Ulk1-S555A knock-in mice to show that loss of phosphorylation of Ulk1 at S555 blunted exercise-induced mitophagy and mildly impairs energy metabolism during exercise in healthy mice. However, the knock-in mice retained exercise training-mediated improvements of endurance capacity and energy metabolism during exercise. These findings suggest that exercise-induced mitophagy through Ulk1 activation is not required for the metabolic adaptation and improved exercise capacity in young, healthy mice.
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Homólogo de la Proteína 1 Relacionada con la Autofagia , Metabolismo Energético , Músculo Esquelético , Condicionamiento Físico Animal , Animales , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Fosforilación , Ratones , Condicionamiento Físico Animal/fisiología , Metabolismo Energético/fisiología , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiología , Masculino , Ratones Endogámicos C57BL , Entrenamiento Aeróbico/métodos , Mitofagia/fisiología , Técnicas de Sustitución del GenRESUMEN
The ß-thalassemias are inherited genetic disorders affecting the hematopoietic system. In ß-thalassemias, more than 350 mutations of the adult ß-globin gene cause the low or absent production of adult hemoglobin (HbA). A clinical parameter affecting the physiology of erythroid cells is the excess of free α-globin. Possible experimental strategies for a reduction in excess free α-globin chains in ß-thalassemia are CRISPR-Cas9-based genome editing of the ß-globin gene, forcing "de novo" HbA production and fetal hemoglobin (HbF) induction. In addition, a reduction in excess free α-globin chains in ß-thalassemia can be achieved by induction of the autophagic process. This process is regulated by the Unc-51-like kinase 1 (Ulk1) gene. The interplay with the PI3K/Akt/TOR pathway, with the activity of the α-globin stabilizing protein (AHSP) and the involvement of microRNAs in autophagy and Ulk1 gene expression, is presented and discussed in the context of identifying novel biomarkers and potential therapeutic targets for ß-thalassemia.
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Autofagia , Talasemia beta , Humanos , Talasemia beta/genética , Talasemia beta/patología , Talasemia beta/metabolismo , Autofagia/genética , Homólogo de la Proteína 1 Relacionada con la Autofagia/metabolismo , Homólogo de la Proteína 1 Relacionada con la Autofagia/genética , Animales , Transducción de Señal , Edición Génica , Péptidos y Proteínas de Señalización IntracelularRESUMEN
The molecular basis for bulk autophagy activation due to a deficiency in essential nutrients such as carbohydrates, amino acids, and nitrogen is well understood. Given autophagy functions to reduce surplus to compensate for scarcity, it theoretically possesses the capability to selectively degrade specific substrates to meet distinct metabolic demands. However, direct evidence is still lacking that substantiates the idea that autophagy selectively targets specific substrates (known as selective autophagy) to address particular nutritional needs. Recently, Gross et al. found that during phosphate starvation (P-S), rather than nitrogen starvation (N-S), yeasts selectively eliminate peroxisomes by dynamically altering the composition of the Atg1/ULK kinase complex (AKC) to adapt to P-S. This study elucidates how the metabolite sensor Pho81 flexibly interacts with AKC and guides selective autophagic clearance of peroxisomes during P-S, providing novel insights into the metabolic contribution of autophagy to special nutritional needs.