RÉSUMÉ
The purpose of the present study is to improve the endothelial progenitor cells (EPC) activation, proliferation, and angiogenesis using enzyme-aided extraction of fucoidan by amyloglucosidase (EAEF-AMG). Enzyme-aided extraction of fucoidan by AMG (EAEF-AMG) significantly increased EPC proliferation by reducing the reactive oxygen species (ROS) and decreasing apoptosis. Notably, EAEF-AMG treated EPCs repressed the colocalization of TSC2/LAMP1 and promoted perinuclear localization of mTOR/LAMP1 and mTOR/Rheb. Moreover, EAEF-AMG enhanced EPC functionalities, including tube formation, cell migration, and wound healing via regulation of AKT/Rheb signaling. Our data provided cell priming protocols to enhance therapeutic applications of EPCs using bioactive compounds for the treatment of CVD.
Sujet(s)
Progéniteurs endothéliaux/effets des médicaments et des substances chimiques , Glucan 1,4-alpha-glucosidase/métabolisme , Polyosides/pharmacologie , Protéines proto-oncogènes c-akt/métabolisme , Transduction du signal/effets des médicaments et des substances chimiques , Apoptose/effets des médicaments et des substances chimiques , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Cellules cultivées , Progéniteurs endothéliaux/métabolisme , Humains , Protéine de membrane-1 associée au lysosome/métabolisme , Néovascularisation physiologique/effets des médicaments et des substances chimiques , Espèces réactives de l'oxygène/métabolisme , Sérine-thréonine kinases TOR/métabolisme , Protéine-2 du complexe de la sclérose tubéreuse/métabolisme , Cicatrisation de plaie/effets des médicaments et des substances chimiquesRÉSUMÉ
Deoxypodophyllotoxin (DPT) is a naturally occurring flavolignan in Anthriscus sylvestris known as cow parsley or wild chervil, and has been reported to have inhibitory effects against several pathological processes including cancer, inflammation and infection. Here, we report the effects of DPT in the fatty liver induced by high fat diet in vivo as well as its regulatory mechanism related with the transcription factor for lipogenic genes such as sterol regulatory element binding protein-1c (SREBP-1c) in vitro. C57BL/6 mice were fed high fat diet for 10 weeks and also orally administrated with DPT for additional 4 weeks. 5 and 10â¯mg/kg of DPT decreased lipid accumulation in the liver induced by high fat diet, as indicated by histological parameters such as Oil Red O staining and hematoxylin & eosin as well as the contents of hepatic triglyceride and cholesterol. In hepatocytes, DPT inhibited the liver X receptor α-mediated SREBP-1c induction and expression of the lipogenic genes, including fatty acid synthase, acetyl-CoA carboxylase and stearoyl-CoA desaturase-1. Moreover, DPT induced AMP-activated protein kinase (AMPK) activation, which has been known to inhibit the expression of SREBP-1c in hepatocyte. Also this compound restored the dysregulation of AMPK and SREBP-1c induced by high fat diet in mice. In conclusion, we demonstrated that DPT significantly inhibited fatty liver by adjusting lipid metabolism coordinated with AMPK activation and SREBP-1c inhibition.
Sujet(s)
AMP-Activated Protein Kinases/métabolisme , Apiaceae/métabolisme , Foie/effets des médicaments et des substances chimiques , Podophyllotoxine/analogues et dérivés , Transduction du signal/effets des médicaments et des substances chimiques , Protéine-1 de liaison à l'élément de régulation des stérols/métabolisme , Animaux , Poids/effets des médicaments et des substances chimiques , Cholestérol/métabolisme , Alimentation riche en graisse , Médicaments issus de plantes chinoises , Cellules HepG2 , Humains , Hydrocarbures fluorés/pharmacologie , Métabolisme lipidique/effets des médicaments et des substances chimiques , Foie/métabolisme , Foie/anatomopathologie , Récepteurs hépatiques X/agonistes , Récepteurs hépatiques X/métabolisme , Mâle , Souris , Souris de lignée C57BL , Podophyllotoxine/pharmacologie , Protéine-1 de liaison à l'élément de régulation des stérols/génétique , Sulfonamides/pharmacologie , Triglycéride/métabolisme , Régulation positive/effets des médicaments et des substances chimiquesRÉSUMÉ
BACKGROUND: A natural compound deoxypodophyllotoxin (DPT) possesses potent anti-proliferative and anti-tumor properties on several cancer types. It triggers cell cycle arrest followed by apoptosis through various cellular processes. However, it is limited to the action mechanism of DPT-mediated cell death modes via apoptosis and autophagy. METHODS: Cell viability assay, morphological changes, annexin-V/propidium iodide (PI) assay, reactive oxygen species (ROS), acridine orange staining, and Western blot analyses were evaluated. RESULTS: We demonstrated that DPT induced both apoptosis and autophagy via production of mitochondrial reactive oxygen species (ROS). DPT suppressed the PI3K/AKT/mTOR signaling cascades to lead autophagy process, resulting from conversion of light chain 3-I (LC3-I) into LC3-II and acidic vesicular organelles (AVOs) formation. Even if DPT-induced ROS were occurred in both apoptosis and autophagy, inhibition of ROS generation enhanced cell viability. Otherwise, 3-methyladeine (3-MA) impeding on autophagy accelerated an apoptotic response caused by DPT. Therefore, these findings suggest that DPT triggers cytoprotective autophagy against cytotoxic apoptosis. CONCLUSION: Autophagy is required for cell survival by inhibition of apoptosis through down-regulation of PI3K/AKT/mTOR pathway against DPT-induced apoptosis in U2OS cells.
Sujet(s)
Antinéoplasiques d'origine végétale/usage thérapeutique , Ostéosarcome/traitement médicamenteux , Inhibiteurs des phosphoinositide-3 kinases , Podophyllotoxine/analogues et dérivés , Protéines proto-oncogènes c-akt/antagonistes et inhibiteurs , Sérine-thréonine kinases TOR/antagonistes et inhibiteurs , Antinéoplasiques d'origine végétale/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Autophagie/effets des médicaments et des substances chimiques , Tumeurs osseuses/traitement médicamenteux , Lignée cellulaire tumorale , Survie cellulaire , Médicaments issus de plantes chinoises , Régulation de l'expression des gènes/effets des médicaments et des substances chimiques , Humains , Podophyllotoxine/pharmacologie , Podophyllotoxine/usage thérapeutique , Espèces réactives de l'oxygèneRÉSUMÉ
Recently, the interplay between autophagy and apoptosis has become an important factor in chemotherapy for cancer treatment. Inhibition of autophagy may be an effective strategy to improve the treatment of chemo-resistant cancer by consistent exposure to chemotherapeutic drugs. However, no reports have clearly elucidated the underlying mechanisms. Therefore, in this study, we assessed whether salinomycin, a promising anticancer drug, induces apoptosis and elucidated potential antitumor mechanisms in chemo-resistant prostate cancer cells. Cell viability assay, Western blot, annexin V/propidium iodide assay, acridine orange (AO) staining, caspase-3 activity assay, reactive oxygen species (ROS) production, and mitochondrial membrane potential were assayed. Our data showed that salinomycin alters the sensitivity of prostate cancer cells to autophagy. Pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, enhanced the salinomycin-induced apoptosis. Notably, salinomycin decreased phosphorylated of AKT and phosphorylated mammalian target of rapamycin (mTOR) in prostate cancer cells. Pretreatment with LY294002, an autophagy and PI3K inhibitor, enhanced the salinomycin-induced apoptosis by decreasing the AKT and mTOR activities and suppressing autophagy. However, pretreatment with PD98059 and SB203580, an extracellular signal-regulated kinases (ERK), and p38 inhibitors, suppressed the salinomycin-induced autophagy by reversing the upregulation of ERK and p38. In addition, pretreatment with N-acetyl-l-cysteine (NAC), an antioxidant, inhibited salinomycin-induced autophagy by suppressing ROS production. Our results suggested that salinomycin induces apoptosis, which was related to ROS-mediated autophagy through regulation of the PI3K/AKT/mTOR and ERK/p38 MAPK signaling pathways.
Sujet(s)
Autophagie/effets des médicaments et des substances chimiques , Extracellular Signal-Regulated MAP Kinases/métabolisme , Phosphatidylinositol 3-kinases/métabolisme , Pyrannes/pharmacologie , Espèces réactives de l'oxygène/métabolisme , Sérine-thréonine kinases TOR/métabolisme , p38 Mitogen-Activated Protein Kinases/métabolisme , Apoptose/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Extracellular Signal-Regulated MAP Kinases/antagonistes et inhibiteurs , Flavonoïdes/pharmacologie , Humains , Imidazoles/pharmacologie , Système de signalisation des MAP kinases/effets des médicaments et des substances chimiques , Mâle , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Inhibiteurs des phosphoinositide-3 kinases , Protéines proto-oncogènes c-akt/antagonistes et inhibiteurs , Protéines proto-oncogènes c-akt/métabolisme , Pyridines/pharmacologie , Sérine-thréonine kinases TOR/antagonistes et inhibiteurs , p38 Mitogen-Activated Protein Kinases/antagonistes et inhibiteursRÉSUMÉ
Lasalocid is an antibiotic from the group of carboxylic ionophores, produced by Streptomyces lasaliensis. But there was limited information of lasalocid on human prostate cancer cells. In the present studies, to better understand its effect in human prostate cancer cells, apoptosis and autophagy associated with possible signal pathways in vitro was examined. Our study showed that lasalocid mediated cell cycle arrest in G0/G1 phase by reducing G1 phase dependent proteins, indicating entering into apoptotic cell death pathway. Lasalocid-induced apoptosis was involved with reactive oxygen species (ROS) production, and mitochondrial hyperpolarization. In addition, lasalocid induced autophagy through microtubule-associated protein 1 light chain 3 (LC-3)-II conversion, acidic vesicular organelles formation and GFP-LC-3 punctuate, which was inhibited by 3-methyladenine (3-MA), a widely used pharmacological inhibitor of autophagy. Furthermore, the autophagic phenomena were mediated by production of ROS, confirming that inhibition of ROS with N-acetyl-l-cysteine, a ROS inhibitor, attenuated lasalocid-triggered autophagy. Inhibition of autophagy with 3-MA enhanced the lasalocid-induced apoptosis through enhanced ROS generation. Taken together, lasalocid should be useful in the search for new potential chemotherapeutic agents for understanding the molecular mechanisms of anticancer in prostate cancer cells.
Sujet(s)
Apoptose/effets des médicaments et des substances chimiques , Autophagie/effets des médicaments et des substances chimiques , Lasalocide/pharmacologie , Tumeurs de la prostate/métabolisme , Tumeurs de la prostate/anatomopathologie , Espèces réactives de l'oxygène/métabolisme , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Points de contrôle de la phase G1 du cycle cellulaire/effets des médicaments et des substances chimiques , Humains , MâleRÉSUMÉ
BACKGROUND: Toyocamycin, an antibiotic agent isolated from Streptomyces species, has been shown to have anticancer and chemopreventive effects on various cancer cells. Until now, Toyocamycin-induced apoptosis has not been reported to be involved in the regulation between mitogen-activated protein kinases (MAPKs) and reactive oxygen species (ROS) production. METHODS: Cell viability assay, western blot, cell-cycle arrest, annexin V/propidium iodide assay, reactive oxygen species (ROS) production, mitochondrial membrane potential and intracellular Ca2+ flux were assayed. RESULTS: We investigated the apoptotic effect of Toyocamycin and the underlying molecular mechanism in prostate cancer PC-3 cells. Toyocamycin treatment resulted in reduced cell viability of PC-3 cells, but not of non-malignant RWPE-1 cells. Toyocamycin enhanced apoptosis, mitochondrial dysfunction, and ROS production in PC-3 cells. In addition, MAPK proteins were activated upon Toyocamycin treatment. The p38 and extracellular signal-regulated kinases (ERK) activities were regulated by ROS-mediated signaling pathway underlying the Toyocamycin-induced apoptosis. Pretreatment with N-acetyl-l-cysteine (NAC) recovered the Toyocamycin-induced mitochondrial dysfunction, ROS, and apoptosis. Additionally, p38 stimulated ROS production and inhibitory effects on ERK activation, while ERK inhibited the ROS production and had no effect on p38 activation. CONCLUSION: ROS-mediated activation of p38/ERK partially contributes to Toyocamycin-induced apoptosis, and p38/ERK MAPKs regulate the ROS production in PC-3 cells.
Sujet(s)
Apoptose/effets des médicaments et des substances chimiques , Extracellular Signal-Regulated MAP Kinases/métabolisme , Tumeurs de la prostate/métabolisme , Espèces réactives de l'oxygène/métabolisme , Toyocamycine/pharmacologie , p38 Mitogen-Activated Protein Kinases/métabolisme , Apoptose/physiologie , Lignée cellulaire tumorale , Survie cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/physiologie , Relation dose-effet des médicaments , Humains , MâleRÉSUMÉ
Deoxypodophyllotoxin (DPT) is a naturally occurring flavolignan isolated from Anthriscus sylvestris. Recently, it has been reported that DPT inhibits tubulin polymerization and induces G2/M cell cycle arrest followed by apoptosis through multiple cellular processes. Despite these findings, details regarding the cellular and molecular mechanisms underlying the DPT-mediated cell death have been poorly understood. To define a mechanism of DPT-mediated cell death response, we examined whether DPT activates signaling pathways for autophagy and apoptosis. We demonstrated that DPT inhibited cell viability and induced apoptosis in prostate cancer cell lines, as evidenced by a mitochondrial membrane potential and expression of apoptosis-related proteins. Reactive oxygen species (ROS), primarily generated from the mitochondria, play an important role in various cellular responses, such as apoptosis and autophagy. DPT significantly triggered mitochondrial ROS, which were detected by MitoSOX, a selective fluorescent dye of mitochondria-derived ROS. Furthermore, DPT induced autophagy through an up-regulation of autophagic biomarkers, including a conversion of microtubule-associated protein 1 light chain 3 - I (LC3-I) into LC3-II and a formation of acidic vesicular organelles. Moreover, mitochondrial ROS promoted AKT-independent autophagy and ERK signaling. The inhibition of autophagy with 3-methyladenine or LC3 knockdown enhanced DPT-induced apoptosis, suggesting that an autophagy plays a protective role in cell survival against apoptotic prostate cancer cells. Additionally, the results from an in vivo xenograft model confirmed that DPT inhibited tumor growth by regulating the apoptosis- and autophagy-related proteins.
RÉSUMÉ
BACKGROUND: Monensin is a carboxyl polyether ionophore that potently inhibits the growth of various cancer cells. Recently, the anticancer effects of monensin have been recognized based on its ability to induce apoptosis in cancer cells. However, anticancer effect of monensin and its mechanism of action have yet to be investigated, especially against human prostate cancer cells. MATERIALS AND METHODS: Cell viability assay, western blot, cell-cycle arrest, annexin V/propidium iodide assay, reactive oxygen species (ROS) production and intracellular Ca2+ flux were assayed. RESULTS: In this study, monensin significantly inhibited cell viability in a dose-dependent manner in prostate cell lines. Moreover, cell growth inhibition by monensin induced G1 phase cell-cycle arrest and apoptosis via regulation of cell cycle- and apoptosis-related proteins in PC-3 cells. In addition, monensin induced the production of ROS and the disruption of Ca2+ homeostasis, that was restored by diphenyleneiodonium, a mitochondrial ROS inhibitor and verapamil, a Ca2+ channel blocker, respectively, as confirmed by pro-caspase-3 activation and poly ADP ribose polymerase cleavage. CONCLUSION: Monensin induces cell-cycle arrest and apoptosis through regulation of cell cycle- and apoptosis-related proteins, resulting in induction of mitochondrial ROS- and Ca2+-dependent apoptosis, respectively.