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The Journal of Biological Chemistry May 1996We have shown previously that wortmannin partially inhibits mitogen-activated protein kinase (MAPK) activated by platelet-activating factor (PAF) in guinea pig...
Wortmannin inhibits mitogen-activated protein kinase activation by platelet-activating factor through a mechanism independent of p85/p110-type phosphatidylinositol 3-kinase.
We have shown previously that wortmannin partially inhibits mitogen-activated protein kinase (MAPK) activated by platelet-activating factor (PAF) in guinea pig neutrophils (Ferby, M. I., Waga, I., Sakanaka, C., Kume, K., and Shimizu, T. (1994) J. Biol. Chem. 269, 30485-30488). To identify whether p85-dependent phosphatidylinositol 3-kinase is a target molecule of wortmannin in this inhibitory process, we established a murine macrophage cell line (P388D1), inducibly expressing a dominant-negative p85, delta p85. Upon induction of delta p85 by isopropyl-beta-D-thiogalactopyranoside, PAF still induced unaltered activation of MAPK, which was inhibited completely by wortmannin and 1,2-bis-(O-aminophenoxy)-ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester in an additive manner. Thus, PAF activates MAPK in P388D1 cells via two distinct pathways, one calcium-dependent and another calcium-independent, but wortmannin-sensitive. The inhibition of calcium-independent activation of MAPK by wortmannin does not involve p85-dependent phosphatidylinositol 3-kinase.
Topics: Androstadienes; Animals; Azepines; Calcium-Calmodulin-Dependent Protein Kinases; Cattle; Enzyme Activation; Enzyme Inhibitors; Mice; Naphthalenes; Phosphatidylinositol 3-Kinases; Phosphotransferases (Alcohol Group Acceptor); Platelet Activating Factor; Transfection; Wortmannin
PubMed: 8662643
DOI: 10.1074/jbc.271.20.11684 -
Life Sciences Jul 2021Effective telomerase-molecular targeted cancer therapy might be a promising approach for the efficient treatment of ovarian cancer. Therefore, folate-functionalized PLGA...
Effective telomerase-molecular targeted cancer therapy might be a promising approach for the efficient treatment of ovarian cancer. Therefore, folate-functionalized PLGA nanoparticles (NPs) were co-loaded with hTERT siRNA, Wortmannin (Wtmn), as a potent PI3K inhibitor, and magnetic nanoparticle (MNPs) as a theranostic agent to gain a multifunctional NPs for targeted drug delivery as well as molecular targeted therapy. HNMR, FTIR, DLS, FE-SEM and TEM were applied to characterize the synthesized NPs. In vitro discharge pattern for siRNA and Wtmn from the dual drug-loaded NPs showed an early fast release followed by a constant release up to 200 h. According to the MRI analysis, by increasing the concentration of FeO in NPs, the weaker T2 signal intensity was enhanced, and a considerable contrast was detected in the MRI images. MTT assay and median-effect analysis showed that the Wtmn/siRNA-loaded MNPs-PLGA-F2 NPs display the most synergistic cytotoxicity on the SKOV-3 ovarian cancer cells. Moreover, the Wtmn/siRNA-loaded MNPs-PLGA-FA NPs could significantly reduce the expression of hTERT, AKT, and p-AKT than the single drug-encapsulated NPs (P < 0.05). Taken together, the findings showed that the multifunctional NPs relying on combinatorial therapy might have considerable potential for effective telomerase-molecular targeted therapy of ovarian cancer.
Topics: Drug Delivery Systems; Female; Folic Acid; Humans; Immunosuppressive Agents; Magnetic Iron Oxide Nanoparticles; Molecular Targeted Therapy; Nanoparticles; Ovarian Neoplasms; Polylactic Acid-Polyglycolic Acid Copolymer; RNA, Small Interfering; Telomerase; Tumor Cells, Cultured; Wortmannin
PubMed: 34004255
DOI: 10.1016/j.lfs.2021.119621 -
Medicinal Research Reviews Sep 2015Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been... (Review)
Review
Although fungi produce highly structurally diverse metabolites, many of which have served as excellent sources of pharmaceuticals, no fungi-derived agent has been approved as a cancer drug so far. This is despite a tremendous amount of research being aimed at the identification of fungal metabolites with promising anticancer activities. This review discusses the results of clinical testing of fungal metabolites and their synthetic derivatives, with the goal to evaluate how far we are from an approved cancer drug of fungal origin. Also, because in vivo studies in animal models are predictive of the efficacy and toxicity of a given compound in a clinical situation, literature describing animal cancer testing of compounds of fungal origin is reviewed as well. Agents showing the potential to advance to clinical trials are also identified. Finally, the technological challenges involved in the exploitation of fungal biodiversity and procurement of sufficient quantities of clinical candidates are discussed, and potential solutions that could be pursued by researchers are highlighted.
Topics: Androstadienes; Animals; Antineoplastic Agents; Aphidicolin; Biological Products; Clinical Trials as Topic; Cyclohexanes; Diketopiperazines; Disease Models, Animal; Drug Design; Drug Resistance, Neoplasm; Fatty Acids, Unsaturated; Female; Fungi; Humans; Macrolides; Male; Mice; Neoplasms; Polycyclic Sesquiterpenes; Sesquiterpenes; Trichothecenes; Wortmannin
PubMed: 25850821
DOI: 10.1002/med.21348 -
Journal of Pharmacological Sciences Feb 2009Endothelin-1 (ET-1) modulates cardiac contractility by cross-talk with norepinephrine (NE) in canine ventricular myocardium. The present experiments were performed to...
Endothelin-1 (ET-1) modulates cardiac contractility by cross-talk with norepinephrine (NE) in canine ventricular myocardium. The present experiments were performed to investigate the influence of wortmannin that has inhibitory action on phosphatidylinositol 3-kinase (PI3-K) (IC50 = 3 nM) and myosin light chain kinase (MLCK) (IC50 = 200 nM) on Ca(2+) signaling and the inotropic effects of ET-1 induced by cross-talk with NE. Experiments were carried out in isolated canine ventricular trabeculae and indo-1/AM-loaded single ventricular cardiomyocytes. ET-1 alone elicited a transient small negative inotropic effect (NIE). In the presence of NE at low (1-10 nM) and high (100 nM) concentrations, ET-1 induced a long-lasting positive inotropic effect (PIE) or a marked sustained NIE, respectively. Wortmannin up to 300 nM did not affect the contractility; and at 1 microM and higher, it decreased the basal contraction without suppressing Ca(2+) transients. Wortmannin (1 microM) inhibited the long-lasting PIE of ET-1 without affecting the ET-1-induced increase in Ca(2+) transients. Wortmannin at the same concentration did not affect the ET-1-induced transient and sustained NIE and the PIE mediated by beta-adrenoceptor stimulation. These results imply that wortmannin exerts selective inhibitory action on the increase in myofilament Ca(2+) sensitivity induced by cross-talk of ET-1 with NE probably through an inhibition of MLCK in canine ventricular myocardium.
Topics: Actin Cytoskeleton; Androstadienes; Animals; Calcium; Calcium Signaling; Depression, Chemical; Dogs; Endothelin-1; Female; Heart Ventricles; Male; Myocardial Contraction; Norepinephrine; Stimulation, Chemical; Wortmannin
PubMed: 19234363
DOI: 10.1254/jphs.08228fp -
Molecular Membrane Biology 1999Homotypic fusion between early endosomes can be reconstituted in vitro. By using wortmannin and LY294002, inhibitors of phosphatidylinositol (Pl) 3-kinase, a requirement... (Review)
Review
Homotypic fusion between early endosomes can be reconstituted in vitro. By using wortmannin and LY294002, inhibitors of phosphatidylinositol (Pl) 3-kinase, a requirement for this activity has been established in order for fusion to proceed efficiently. It has been shown that Pl 3-kinase activity is required downstream of rab5 activation, although a large excess of activated rab5 can overcome wortmannin inhibition. A series of experiments have also been performed which indicate a role for early endosomal autoantigen 1 (EEA1) in determining fusion efficiency. EEA1 dissociates from membranes following wortmannin treatment. It is proposed that the requirement of endosome fusion for Pl 3-kinase activity is to promote the association of EEA1 with endosomes.
Topics: Androstadienes; Animals; Carrier Proteins; Endosomes; Enzyme Inhibitors; GTP-Binding Proteins; Membrane Fusion; Membrane Proteins; Models, Biological; N-Ethylmaleimide-Sensitive Proteins; Phosphatidylinositol 3-Kinases; Signal Transduction; Soluble N-Ethylmaleimide-Sensitive Factor Attachment Proteins; Vesicular Transport Proteins; Wortmannin; rab5 GTP-Binding Proteins
PubMed: 10332740
DOI: 10.1080/096876899294788 -
Journal of Physiology and Biochemistry Mar 2016Ischemic preconditioning (IPC) is one of the most powerful interventions to reduce ischemia-reperfusion injury. The aim of the present study was to investigate the...
Ischemic preconditioning (IPC) is one of the most powerful interventions to reduce ischemia-reperfusion injury. The aim of the present study was to investigate the involvement of the phosphatidylinositol-3-kinases (PI3Ks) family in cardioprotection exerted by IPC and the relationship between preservation of mitochondrial morphology and ATP synthesis capacity. In this regard, macroautophagy (autophagy) is considered a dynamic process involved in the replacement of aged or defective organelles under physiological conditions. IPC consisted of four 5-min cycles of ischemia-reperfusion followed by sustained ischemia. Wortmannin (W), a PI3K family inhibitor, was added to the perfusion medium to study the involvement of autophagy in the beneficial effects of IPC. In the present study, LC3-II/I expression was significantly increased in the IPC group when compared with the control group. The hearts subjected to IPC showed greater degradation of p62 than control groups, establishing the existence of an autophagic flow. Electron microscopy showed that IPC preserves the structural integrity of mitochondria after ischemia and at the end of reperfusion. Moreover, hearts subjected to IPC exhibited increased mitochondrial ATP synthesis. The beneficial effects of IPC were abolished by W in all trials of this study, abolishing the differences between the IPC and control groups. These results suggest that IPC could partly reduce injury by ischemia-reperfusion (I/R) by decreasing mitochondrial damage and promoting autophagy. Since W is a nonspecific inhibitor of the PI3Ks family, further research is required to confirm participation of PI3K in the response to IPC.
Topics: Androstadienes; Animals; Cardiotonic Agents; Ischemic Preconditioning; Rats; Reperfusion Injury; Wortmannin
PubMed: 26746207
DOI: 10.1007/s13105-015-0460-6 -
Calcified Tissue International Apr 1995Phosphatidylinositol 3-kinase (Pl3-k) is involved in cellular signaling via the phosphoinositol pathway leading to mitogenesis in response to growth factors in...
Phosphatidylinositol 3-kinase (Pl3-k) is involved in cellular signaling via the phosphoinositol pathway leading to mitogenesis in response to growth factors in proliferating cells, as well as cytoskeletal changes and secretory responses in terminally differentiated cells. The fungal metabolite, wortmannin, is a potent and selective inhibitor of Pl3-k at nanomolar concentrations. We show that wortmannin dose-dependently (0.001-1 microM) inhibits bone resorption by isolated rat osteoclasts in the bone slice pit assay with an IC50 of approximately 5 nM. Wortmannin was not cytotoxic since osteoclast morphology and survival on bone slices was unaffected by concentrations up to 1 microM. Since primary osteoclasts are terminally differentiated cells and osteoclast cytoplasmic spreading and morphology was unaffected by wortmannin, we suggest that Pl3-k signaling is involved in vesicle exocytosis and ruffled border membrane formation that are required for osteoclastic bone resorption to take place.
Topics: Androstadienes; Animals; Bone Resorption; Culture Techniques; Dose-Response Relationship, Drug; Osteoclasts; Phosphatidylinositol 3-Kinases; Phosphotransferases (Alcohol Group Acceptor); Rats; Wortmannin
PubMed: 7767847
DOI: 10.1007/BF00318056 -
Molecular and Cellular Endocrinology Aug 1995The insulin receptor substrate-1 (IRS-1) is expressed in 3T3-L1 adipocytes and is involved in at least some insulin responses, notably mitogenesis. Chronic exposure to...
The insulin receptor substrate-1 (IRS-1) is expressed in 3T3-L1 adipocytes and is involved in at least some insulin responses, notably mitogenesis. Chronic exposure to insulin down regulates IRS-1 in these cells by stimulating its degradation (Rice, K.M., Turnbow, M.A. and Garner, C.W. (1993) Biochem. Biophys. Res. Commun. 190, 961-967). This insulin response was completely inhibited by wortmannin and LY294002 (2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one), two inhibitors of phosphatidylinositol 3-kinase (PI 3-kinase). Neither wortmannin nor LY294002 had any effect on the calcium-dependent degradation of IRS-1 in vitro nor did they inhibit the phosphorylation of IRS-1 in vitro. In addition, neomycin, a cationic aminoglycoside antibiotic that binds to phosphoinositides, inhibited the insulin-induced down-regulation of IRS-1 in 3T3-L1 adipocytes and, also, the C8-PIP3-stimulated degradation of IRS-1 in vitro. These results suggest that PI 3-kinase and its 3-phosphoinositide products mediate the insulin-induced down-regulation of IRS-1 in 3T3-L1 adipocytes.
Topics: 3T3 Cells; Adipocytes; Androstadienes; Animals; Calcium-Binding Proteins; Chromones; Enzyme Inhibitors; Insulin; Insulin Receptor Substrate Proteins; Mice; Morpholines; Neomycin; Phosphatidylinositol 3-Kinases; Phosphatidylinositol Phosphates; Phosphoproteins; Phosphotransferases (Alcohol Group Acceptor); Wortmannin
PubMed: 8674815
DOI: 10.1016/0303-7207(95)03622-e -
Natural Product Reports Mar 2012Natural products have been widely used to dissect the basic mechanisms of fundamental life science and as clinical therapeutics. Recently, there has been significant... (Review)
Review
Natural products have been widely used to dissect the basic mechanisms of fundamental life science and as clinical therapeutics. Recently, there has been significant interest in discovering new chemical pharmacophores in natural products to fulfil the vast demand for novel kinase inhibitors and address critical unmet medical needs with respect to signal transduction pathways. In this review, we summarize the history of several different classes of natural product-derived kinase inhibitors, discuss their kinome-wide target profiles and examine their structural binding modes based on available 3D X-ray structures. In particular, their origin, target activity, selectivity, scope and potential therapeutic development are highlighted against the backdrop of medicinal chemistry.
Topics: Androstadienes; Biological Products; Drug Design; Humans; Molecular Structure; Protein Kinase Inhibitors; Wortmannin
PubMed: 22231144
DOI: 10.1039/c2np00097k -
The Journal of Pharmacology and... Apr 1996The possible importance of phosphatidylinositol (PI) 3-kinase activity in bone resorption activity in vitro and in vivo were evaluated with synthetic wortmannin analogs...
The possible importance of phosphatidylinositol (PI) 3-kinase activity in bone resorption activity in vitro and in vivo were evaluated with synthetic wortmannin analogs in two in vitro bone resorption assays, two in vitro assays for PI 3-kinase activity and for the first time, in two in vivo rat models. Wortmannin and LY301497 were shown to be potent, dose-dependent inhibitors of the bone resorption activity of differentiating chicken osteoclast-like cells and isolated rat osteoclasts. A similar structure/activity profile and potency relationship was observed for the inhibition of osteoclastic activity and of bovine PI 3-kinase activity with purified enzyme, as well as direct inhibition of the PI 3-kinase activity of chicken osteoclast lysates. These in vitro data identified LY301497 as an inhibitor of bone resorption that is 10-fold more potent than wortmannin itself, and the most potent inhibitor of PI 3-kinase activity identified thus far. Wortmannin and analogs also lowered the osteoclast-dependent serum calcium levels like salmon calcitonin in a rat model of secondary hyperparathyroidism. More directly, oral administration of wortmannin analogs prevented the estrogen deficiency-induced loss of trabecular bone in the metaphysis of proximal tibiae from ovariectomized rats. Wortmannin, and especially LY301497, compared favorably in potency in vivo to orally administered estrogen. Taken together, these data are strong evidence to show that wortmannin analogs directly block osteoclastic activity in vitro and in vivo, and confirm that PI 3-kinase activity is a necessary step in the regulation of bone resorption. PI 3-kinase activity appears to be an important component of ovariectomy-stimulated bone loss in rats. This mechanism is supported by the finding that wortmannin had little effect on the activity of myosin light chain kinase in intact osteoclasts. The use of LY301497 should prove useful in elucidating specific molecular interactions important in bone resorption and other PI 3-kinase-mediated cell processes. These data also suggest the possible therapeutic utility of wortmannin analogs to treat conditions characterized by excessive bone loss, such as hyperparathyroidism or hypercalcemia of malignency.
Topics: Androstadienes; Animals; Bone Resorption; Bone and Bones; Cattle; Chickens; Enzyme Inhibitors; Female; Male; Osteoclasts; Phosphatidylinositol 3-Kinases; Phosphotransferases (Alcohol Group Acceptor); Rats; Rats, Sprague-Dawley; Structure-Activity Relationship; Wortmannin
PubMed: 8613966
DOI: No ID Found