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Howarth FC, Qureshi MA, Jayaprakash P, Parekh K, Oz M, Dobrzynski H, Adrian TE. The Pattern of mRNA Expression Is Changed in Sinoatrial Node from Goto-Kakizaki Type 2 Diabetic Rat Heart. J Diabetes Res 2018; 2018:8454078. [PMID: 30246030 PMCID: PMC6139199 DOI: 10.1155/2018/8454078] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Revised: 07/16/2018] [Accepted: 08/12/2018] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND In vivo experiments in Goto-Kakizaki (GK) type 2 diabetic rats have demonstrated reductions in heart rate from a young age. The expression of genes encoding more than 70 proteins that are associated with the generation and conduction of electrical activity in the GK sinoatrial node (SAN) have been evaluated to further clarify the molecular basis of the low heart rate. MATERIALS AND METHODS Heart rate and expression of genes were evaluated with an extracellular electrode and real-time RT-PCR, respectively. Rats aged 12-13 months were employed in these experiments. RESULTS Isolated spontaneous heart rate was reduced in GK heart (161 ± 12 bpm) compared to controls (229 ± 11 bpm). There were many differences in expression of mRNA, and some of these differences were of particular interest. Compared to control SAN, expression of some genes were downregulated in GK-SAN: gap junction, Gja1 (Cx43), Gja5 (Cx40), Gjc1 (Cx45), and Gjd3 (Cx31.9); cell membrane transport, Trpc1 (TRPC1) and Trpc6 (TRPC6); hyperpolarization-activated cyclic nucleotide-gated channels, Hcn1 (HCN1) and Hcn4 (HCN4); calcium channels, Cacna1d (Cav1.3), Cacna1g (Cav3.1), Cacna1h (Cav3.2), Cacna2d1 (Cavα2δ1), Cacna2d3 (Cavα2δ3), and Cacng4 (Cav γ 4); and potassium channels, Kcna2 (Kv1.2), Kcna4 (Kv1.4), Kcna5 (Kv1.5), Kcnb1 (Kv2.1), Kcnd3 (Kv4.3), Kcnj2 (Kir2.1), Kcnk1 (TWIK1), Kcnk5 (K2P5.1), Kcnk6 (TWIK2), and Kcnn2 (SK2) whilst others were upregulated in GK-SAN: Ryr2 (RYR2) and Nppb (BNP). CONCLUSIONS This study provides new insight into the changing expression of genes in the sinoatrial node of diabetic heart.
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MESH Headings
- Action Potentials
- Animals
- Arrhythmias, Cardiac/etiology
- Arrhythmias, Cardiac/genetics
- Arrhythmias, Cardiac/metabolism
- Arrhythmias, Cardiac/physiopathology
- Diabetes Mellitus, Type 2/complications
- Diabetes Mellitus, Type 2/genetics
- Diabetes Mellitus, Type 2/metabolism
- Diabetic Cardiomyopathies/etiology
- Diabetic Cardiomyopathies/genetics
- Diabetic Cardiomyopathies/metabolism
- Diabetic Cardiomyopathies/physiopathology
- Disease Models, Animal
- Gene Expression Regulation
- Heart Rate/genetics
- Isolated Heart Preparation
- Male
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats, Wistar
- Sinoatrial Node/metabolism
- Sinoatrial Node/physiopathology
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Affiliation(s)
- F. C. Howarth
- Department of Physiology, College of Medicine & Health Sciences, UAE University, Al Ain, UAE
| | - M. A. Qureshi
- Department of Physiology, College of Medicine & Health Sciences, UAE University, Al Ain, UAE
| | - P. Jayaprakash
- Department of Pharmacology, College of Medicine & Health Sciences, UAE University, Al Ain, UAE
| | - K. Parekh
- Department of Physiology, College of Medicine & Health Sciences, UAE University, Al Ain, UAE
| | - M. Oz
- Department of Pharmacology, College of Medicine & Health Sciences, UAE University, Al Ain, UAE
| | - H. Dobrzynski
- Cardiovascular Sciences, University of Manchester, Manchester, UK
| | - T. E. Adrian
- Department of Basic Medical Sciences, Mohammed Bin Rashid University of Medicine & Health Sciences, Dubai, UAE
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Sajwani FH, Collin P, Adrian TE. Frondoside A potentiates the effects of conventional therapeutic agents in acute leukemia. Leuk Res 2017; 63:98-108. [PMID: 29127862 DOI: 10.1016/j.leukres.2017.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Revised: 10/30/2017] [Accepted: 11/02/2017] [Indexed: 10/18/2022]
Abstract
Acute leukemia is the major cause of mortality in hematological malignancies. Despite improvement of survival with current chemotherapies, patients die from the disease or side-effects of treatment. Thus, new therapeutic agents are needed. Frondoside A is a triterpenoid glycoside originally isolated from the sea cucumber, Cucumaria frondosa that has potent antitumor effects in various cancers. The current study investigated the effects of frondoside A in acute leukemia cell lines alone and in combination with drugs used for this malignancy. This study is the first comparing the efficacy of frondoside A to available conventional drugs. The acute leukemia cell lines used were CCRF-CEM, HL-60 and THP-1. Cells were cultured and treated with different concentrations of vincristine sulphate, asparaginase and prednisolone alone and in combination with frondoside A. The inhibitory concentration 50 (IC50) for each compound was determined for the cell lines. CCRF-CEM cells were very sensitive to frondoside A treatment while HL-60 and THP1 were less sensitive. Frondoside A markedly enhanced the anticancer effects of all of the conventional drugs. Synergistic effects were seen with most of the combinations. Frondoside A may be valuable in the treatment of acute leukemia, particularly when used in combination with current therapeutic drugs.
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Affiliation(s)
- F H Sajwani
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates.
| | - P Collin
- Coastside Bio Resources, Deer Isle, ME 04627, USA
| | - T E Adrian
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates.
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Marion MH, Van Turnhout MC, Van Der Schaft DWJ, Sahlgren CM, Goumans MJ, Bouten CVC, Vuorenpaa H, Penttinen K, Sarkanen R, Ylikomi T, Heinonen T, Aalto-Setala K, Grimaldi V, Aprile M, Esposito R, Maiello C, Soricelli A, Colantuoni V, Costa V, Ciccodicola A, Napoli C, Rowe GC, Johnson K, Arany ZP, Del Monte F, D'aurizio R, Kusmic C, Nicolini G, Baumgart M, Groth M, Ucciferri N, Iervasi G, Pitto L, Pipicz M, Gaspar R, Siska A, Foldesi I, Kiss K, Bencsik P, Thum T, Batkai S, Csont T, Haan JJ, Bosch L, Brans MAD, Van De Weg SM, Deddens JC, Lee SJ, Sluijter JPG, Pasterkamp G, Werner I, Projahn D, Staudt M, Curaj A, Soenmez TT, Simsekyilmaz S, Hackeng TM, Von Hundelshausen P, Koenen RR, Weber C, Liehn EA, Santos-Martinez M, Medina C, Watson C, Mcdonald K, Gilmer J, Ledwidge M, Song SH, Lee MY, Park MH, Choi JC, Ahn JH, Park JS, Oh JH, Choi JH, Lee HC, Cha KS, Hong TJ, Kudryavtsev I, Serebryakova M, Malashicheva A, Shishkova A, Zhiduleva E, Moiseeva O, Durisova M, Blaha M, Melenovsky V, Pirk J, Kautzner J, Petelina TI, Gapon LI, Gorbatenko EA, Potolinskaya YV, Arkhipova EV, Solodenkova KS, Osadchuk MA, Dutra MF, Oliveira FCB, Silva MM, Passos-Silva DG, Goncalves R, Santos RAS, Da Silva RF, Gavrilescu CM, Paraschiv CM, Manea P, Strat LC, Gomez JMG, Merino D, Hurle MA, Nistal JF, Aires A, Cortajarena AL, Villar AV, Abramowitz J, Birnbaumer L, Gourine AV, Tinker A, Takamura M, Takashima S, Inoue O, Misu H, Takamura T, Kaneko S, Alieva TOHIRA, Mougenot N, Dufilho M, Hatem S, Siegbahn A, Kostina AS, Uspensky VE, Moiseeva OM, Kostareva AA, Malashicheva AB, Van Dijk CGM, Chrifi I, Verhaar MC, Duncker DJ, Cheng C, Sturza A, Petrus A, Duicu O, Kiss L, Danila M, Baczko I, Jost N, Gotzhein F, Schon J, Schwarzl M, Hinrichs S, Blankenberg S, Volker U, Hammer E, Westermann D, Martinez-Martinez E, Arrieta V, Fernandez-Celis A, Jimenez-Alfaro L, Melero A, Alvarez-Asiain V, Cachofeiro V, Lopez-Andres N, Tribulova N, Wallukat G, Knezl V, Radosinska J, Barancik M, Tsinlikov I, Tsinlikova I, Nicoloff G, Blazhev A, Pesevski Z, Kvasilova A, Stopkova T, Eckhardt A, Buffinton CM, Nanka O, Kercheva M, Suslova T, Gusakova A, Ryabova T, Markov V, Karpov R, Seemann H, Alcantara TC, Santuchi MDEC, Fonseca SG, Da Silva RF, Barallobre-Barreiro J, Oklu R, Fava M, Baig F, Yin X, Albadawi H, Jahangiri M, Stoughton J, Mayr M, Podliesna SP, Veerman CCV, Verkerk AOV, Klerk MK, Lodder EML, Mengarelli IM, Bezzina CRB, Remme CAR, Takacs H, Polyak A, Morvay N, Lepran I, Tiszlavicz L, Nagy N, Ordog B, Farkas A, Forster T, Varro A, Farkas AS, Jayaprakash P, Parekh K, Ferdous Z, Oz M, Dobrzynski H, Adrian TE, Landi S, Bonzanni M, D'souza A, Boyett M, Bucchi A, Baruscotti M, Difrancesco D, Barbuti A, Kui P, Takacs H, Oravecz K, Hezso T, Polyak A, Levijoki J, Pollesello P, Koskelainen T, Otsomaa L, Farkas AS, Papp JGY, Varro A, Toth A, Acsai K, Dini L, Mazzoni L, Sartiani L, Cerbai E, Mugelli A, Svatunkova J, Sedmera D, Deffge C, Baer C, Weinert S, Braun-Dullaeus RC, Herold J, Cassar AC, Zahra GZ, Pllaha EP, Dingli PD, Montefort SM, Xuereb RGX, Aschacher T, Messner B, Eichmair E, Mohl W, Reglin B, Rong W, Nitzsche B, Maibier M, Guimaraes P, Ruggeri A, Secomb TW, Pries AR, Baranowska-Kuczko M, Karpinska O, Kusaczuk M, Malinowska B, Kozlowska H, Demikhova N, Vynnychenko L, Prykhodko O, Grechanyk N, Kuryata A, Cottrill KA, Du L, Bjorck HM, Maleki S, Franco-Cereceda A, Chan SY, Eriksson P, Giebe S, Cockcroft N, Hewitt K, Brux M, Brunssen C, Tarasov AA, Davidov SI, Reznikova EA, Tapia Abellan A, Angosto Bazarra D, Pelegrin Vivancos P, Montoro Garcia S, Kastl SP, Pongratz T, Goliasch G, Gaspar L, Maurer G, Huber K, Dostal E, Pfaffenberger S, Oravec S, Wojta J, Speidl WS, Osipova I, Sopotova I, Eligini S, Cosentino N, Marenzi G, Tremoli E, Rami M, Ring L, Steffens S, Gur O, Gurkan S, Mangold A, Scherz T, Panzenboeck A, Staier N, Heidari H, Mueller J, Lang IM, Osipova I, Sopotova I, Gatsiou A, Stamatelopoulos K, Perisic L, John D, Lunella FF, Eriksson P, Hedin U, Zeiher A, Dimmeler S, Nunez L, Moure R, Marron-Linares G, Flores X, Aldama G, Salgado J, Calvino R, Tomas M, Bou G, Vazquez N, Hermida-Prieto M, Vazquez-Rodriguez JM, Amit U, Landa N, Kain D, Tyomkin D, David A, Leor J, Hohensinner PJ, Baumgartner J, Krychtiuk KA, Maurer G, Huber K, Baik N, Miles LA, Wojta J, Seeman H, Montecucco F, Da Silva AR, Costa-Fraga FP, Anguenot L, Mach FP, Santos RAS, Stergiopulos N, Da Silva RF, Kupreishvili K, Vonk ABA, Smulders YM, Van Hinsbergh VWM, Stooker W, Niessen HWM, Krijnen PAJ, Ashmawy MM, Salama MA, Elamrosy MZ, Juettner R, Rathjen FG, Bito V, Crocini C, Ferrantini C, Gabbrielli T, Silvestri L, Coppini R, Tesi C, Cerbai E, Poggesi C, Pavone FS, Sacconi L, Mackova K, Zahradnik I, Zahradnikova A, Diaz I, Sanchez De Rojas De Pedro E, Hmadcha K, Calderon Sanchez E, Benitah JP, Gomez AM, Smani T, Ordonez A, Afanasiev SA, Egorova MV, Popov SV, Wu Qing P, Cheng X, Carnicka S, Pancza D, Jasova M, Kancirova I, Ferko M, Ravingerova T, Wu S, Schneider M, Marggraf V, Verfuerth L, Frede S, Boehm O, Dewald O, Baumgarten G, Kim SC, Farkasova V, Gablovsky I, Bernatova I, Ravingerova T, Nosar V, Portnychenko A, Drevytska T, Mankovska I, Gogvadze V, Sejersen T, Kostareva A, Sturza A, Wolf A, Privistirescu A, Danila M, Muntean D, O ' Gara P, Sanchez-Alonso JL, Harding SE, Lyon AR, Prando V, Pianca N, Lo Verso F, Milan G, Pesce P, Sandri M, Mongillo M, Beffagna G, Poloni G, Dazzo E, Sabatelli P, Doliana R, Polishchuk R, Carnevale D, Lembo G, Bonaldo P, Braghetta P, Rampazzo A, Cairo M, Giralt M, Villarroya F, Planavila A, Biesbroek PS, Emmens RWE, Juffermans LJM, Van Der Wall AC, Van Rossum AC, Niessen JWM, Krijnen PAJ, Moor Morris T, Dilanian G, Farahmand P, Puceat M, Hatem S, Gambino G, Petraglia L, Elia A, Komici K, Femminella GD, D'amico ML, Pagano G, Cannavo A, Liccardo D, Koch WJ, Nolano M, Leosco D, Ferrara N, Rengo G, Amit U, Landa N, Kain D, Leor J, Neary R, Shiels L, Watson C, Baugh J, Palacios B, Escobar B, Alonso AV, Guzman G, Ruiz-Cabello J, Jimenez-Borreguero LJ, Martin-Puig S, Lakomkin VL, Lukoshkova EV, Abramov AA, Gramovich VV, Vyborov ON, Ermishkin VV, Undrovinas NA, Shirinsky VP, Smilde BJ, Woudstra L, Fong Hing G, Wouters D, Zeerleder S, Murk JL, Van Ham SM, Heymans S, Juffermans LJM, Van Rossum AC, Niessen JWM, Krijnen PAJ, Krakhmalova O, Van Groen D, Bogaards SJP, Schalij I, Portnichenko GV, Tumanovska LV, Goshovska YV, Lapikova-Bryhinska TU, Nagibin VS, Dosenko VE, Mendes-Ferreira P, Maia-Rocha C, Santos-Ribeiro D, Potus F, Breuils-Bonnet S, Provencher S, Bonnet S, Rademaker M, Leite-Moreira AF, Bras-Silva C, Lopes J, Kuryata O, Lusynets T, Alikulov I, Nourddine M, Azzouzi L, Habbal R, Tserendavaa SUMIYA, Enkhtaivan ODKHUU, Enkhtaivan ODKHUU, Shagdar ZORIGO, Shagdar ZORIGO, Malchinkhuu MUNKHZ, Malchinkhuu MUNLHZ, Koval S, Starchenko T, Mourino-Alvarez L, Gonzalez-Calero L, Sastre-Oliva T, Lopez JA, Vazquez J, Alvarez-Llamas G, Ruilope LUISM, De La Cuesta F, Barderas MG, Bozzini S, D'angelo A, Pelissero G. Poster session 3Cell growth, differentiation and stem cells - Heart511The role of the endocannabinoid system in modelling muscular dystrophy cardiac disease with induced pluripotent stem cells.512An emerging role of T lymphocytes in cardiac regenerative processes in heart failure due to dilated cardiomyopathy513Canonical wnt signaling reverses the ‘aged/senescent’ human endogenous cardiac stem cell phenotype514Hippo signalling modulates survival of human induced pluripotent stem cell-derived cardiomyocytes515Biocompatibility of mesenchymal stem cells with a spider silk matrix and its potential use as scaffold for cardiac tissue regeneration516A snapshot of genome-wide transcription in human induced pluripotent stem cell-derived hepatocyte-like cells (iPSC-HLCs)517Can NOS/sGC/cGK1 pathway trigger the differentiation and maturation of mouse embryonic stem cells (ESCs)?518Introduction of external Ik1 to human-induced pluripotent stem cell-derived cardiomyocytes via Ik1-expressing HEK293519Cell therapy of the heart studied using adult myocardial slices in vitro520Enhancement of the paracrine potential of human adipose derived stem cells when cultured as spheroid bodies521Mechanosensitivity of cardiomyocyte progenitor cells: the strain response in 2D and 3D environments522The effect of the vascular-like network on the maturation of the human induced pluripotent stem cell derived cardiomyocytes.Transcriptional control and RNA species - Heart525Gene expression regulation in heart failure: from pathobiology to bioinformatics526Human transcriptome in idiopathic dilated cardiomyopathy - a novel high throughput screening527A high-throghput approach unveils putative miRNA-mediated mitochondria-targeted cardioprotective circuits activated by T3 in the post ischemia reperfusion setting528The effect of uraemia on the expression of miR-212/132 and the calcineurin pathway in the rat heartCytokines and cellular inflammation - Heart531Lack of growth differentiation factor 15 aggravates adverse cardiac remodeling upon pressure-overload in mice532Blocking heteromerization of platelet chemokines ccl5 and cxcl4 reduces inflammation and preserves heart function after myocardial infarction533Is there an association between low-dose aspirin use and clinical outcome in HFPEF? Implications of modulating monocyte function and inflammatory mediator release534N-terminal truncated intracellular matrix metalloproteinase-2 expression in diabetic heart.535Expression of CD39 and CD73 on peripheral T-cell subsets in calcific aortic stenosis536Mast cells in the atrial myocardium of patients with atrial fibrillation: a comparison with patients in sinus rhythm539Characteristics of the inflammatory response in patients with coronary artery disease and arterial hypertension540Pro-inflammatory cytokines as cardiovascular events predictors in rheumatoid arthritis and asymptomatic atherosclerosis541Characterization of FVB/N murinic bone marrow-derived macrophage polarization into M1 and M2 phenotypes542The biological expression and thoracic anterior pain syndromeSignal transduction - Heart545The association of heat shock protein 90 and TGFbeta receptor I is involved in collagen production during cardiac remodelling in aortic-banded mice546Loss of the inhibitory GalphaO protein in the rostral ventrolateral medulla of the brainstem leads to abnormalities in cardiovascular reflexes and altered ventricular excitablitiy547Selenoprotein P regulates pressure overload-induced cardiac remodeling548Study of adenylyl cyclase activity in erythrocyte membranes in patients with chronic heart failure549Direct thrombin inhibitors inhibit atrial myocardium hypertrophy in a rat model of heart failure and atrial remodeling550Tissue factor / FVIIa transactivates the IGF-1R by a Src-dependent phosphorylation of caveolin-1551Notch signaling is differently altered in endothelial and smooth muscle cells of ascending aortic aneurysm patients552Frizzled 5 expression is essential for endothelial proliferation and migration553Modulation of vascular function and ROS production by novel synthetic benzopyran analogues in diabetes mellitusExtracellular matrix and fibrosis - Heart556Cardiac fibroblasts as inflammatory supporter cells trigger cardiac inflammation in heart failure557A role for galectin-3 in calcific aortic valve stenosis558Omega-3 polyunsaturated fatty acids- can they decrease risk for ventricular fibrillation?559Serum levels of elastin derived peptides and circulating elastin-antielastin immune complexes in sera of patients with coronary artery disease560Endocardial fibroelastosis is secondary to hemodynamic alterations in the chick model of hypoplastic left heart syndrome561Dynamics of serum levels of matrix metalloproteinases in primary anterior STEMI patients564Deletion of the alpha-7 nicotinic acetylcholine receptor changes the vascular remodeling induced by transverse aortic constriction in mice.565Extracellular matrix remodelling in response to venous hypertension: proteomics of human varicose veinsIon channels, ion exchangers and cellular electrophysiology - Heart568Microtubule-associated protein RP/EB family member 1 modulates sodium channel trafficking and cardiac conduction569Investigation of electrophysiological abnormalities in a rabbit athlete's heart model570Upregulation of expression of multiple genes in the atrioventricular node of streptozotocin-induced diabetic rat571miR-1 as a regulator of sinoatrial rhythm in endurance training adaptation572Selective sodium-calcium exchanger inhibition reduces myocardial dysfunction associated with hypokalaemia and ventricular fibrillation573Effect of racemic and levo-methadone on action potential of human ventricular cardiomyocytes574Acute temperature effects on the chick embryonic heart functionVasculogenesis, angiogenesis and arteriogenesis577Clinical improvement and enhanced collateral vessel growth after monocyte transplantation in mice578The role of HIF-1 alpha, VEGF and obstructive sleep apnoea in the development of coronary collateral circulation579Initiating cardiac repair with a trans-coronary sinus catheter intervention in an ischemia/reperfusion porcine animal model580Early adaptation of pre-existing collaterals after acute arteriolar and venular microocclusion: an in vivo study in chick chorioallantoic membraneEndothelium583EDH-type responses to the activator of potassium KCa2.3 and KCa3.1 channels SKA-31 in the small mesenteric artery from spontaneously hypertensive rats584The peculiarities of endothelial dysfunction in patients with chronic renocardial syndrome585Endothelial dysfunction, atherosclerosis of the carotid arteries and level of leptin in patient with coronary heart disease in combination with hepatic steatosis depend from body mass index.586Role of non-coding RNAs in thoracic aortic aneurysm associated with bicuspid aortic valve587Cigarette smoke extract abrogates atheroprotective effects of high laminar flow on endothelial function588The prognostic value of anti-connective tissue antibodies in coronary heart disease and asymptomatic atherosclerosis589Novel potential properties of bioactive peptides from spanish dry-cured ham on the endothelium.Lipids592Intermediate density lipoprotein is associated with monocyte subset distribution in patients with stable atherosclerosis593The characteristics of dyslipidemia in rheumatoid arthritisAtherosclerosis596Macrophages differentiated in vitro are heterogeneous: morphological and functional profile in patients with coronary artery disease597Palmitoylethanolamide promotes anti-inflammatory phenotype of macrophages and attenuates plaque formation in ApoE-/- mice598Amiodarone versus esmolol in the perioperative period: an in vitro study of coronary artery bypass grafts599BMPRII signaling of fibrocytes, a mesenchymal progenitor cell population, is increased in STEMI and dyslipidemia600The characteristics of atherogenesis and systemic inflammation in rheumatoid arthritis601Role of adenosine-to-inosine RNA editing in human atherosclerosis602Presence of bacterial DNA in thrombus aspirates of patients with myocardial infarction603Novel E-selectin binding polymers reduce atherosclerotic lesions in ApoE(-/-) mice604Differential expression of the plasminogen receptor Plg-RKT in monocyte and macrophage subsets - possible functional consequences in atherogenesis605Apelin-13 treatment enhances the stability of atherosclerotic plaques606Mast cells are increased in the media of coronary lesions in patients with myocardial infarction and favor atherosclerotic plaque instability607Association of neutrophil to lymphocyte ratio with presence of isolated coronary artery ectasiaCalcium fluxes and excitation-contraction coupling610The coxsackie- and adenovirus receptor (CAR) regulates calcium homeostasis in the developing heart611HMW-AGEs application acutely reduces ICaL in adult cardiomyocytes612Measuring electrical conductibility of cardiac T-tubular systems613Postnatal development of cardiac excitation-contraction coupling in rats614Role of altered Ca2+ homeostasis during adverse cardiac remodeling after ischemia/reperfusion615Experimental study of sarcoplasmic reticulum dysfunction and energetic metabolism in failing myocardium associated with diabetes mellitusHibernation, stunning and preconditioning618Volatile anesthetic preconditioning attenuates ischemic-reperfusion injury in type II diabetic patients undergoing on-pump heart surgery619The effect of early and delayed phase of remote ischemic preconditioning on ischemia-reperfusion injury in the isolated hearts of healthy and diabetic rats620Post-conditioning with 1668-thioate leads to attenuation of the inflammatory response and remodeling with less fibrosis and better left ventricular function in a murine model of myocardial infarction621Maturation-related changes in response to ischemia-reperfusion injury and in effects of classical ischemic preconditioning and remote preconditioningMitochondria and energetics624Phase changes in myocardial mitochondrial respiration caused by hypoxic preconditioning or periodic hypoxic training625Desmin mutations depress mitochondrial metabolism626Methylene blue modulates mitochondrial function and monoamine oxidases-related ROS production in diabetic rat hearts627Doxorubicin modulates the real-time oxygen consumption rate of freshly isolated adult rat and human ventricular cardiomyocytesCardiomyopathies and fibrosis630Effects of genetic or pharmacologic inhibition of the ubiquitin/proteasome system on myocardial proteostasis and cardiac function631Suppression of Wnt signalling in a desmoglein-2 transgenic mouse model for arrhythmogenic cardiomyopathy632Cold-induced cardiac hypertrophy is reversed after thermo-neutral deacclimatization633CD45 is a sensitive marker to diagnose lymphocytic myocarditis in endomyocardial biopsies of living patients and in autopsies634Atrial epicardial adipose tissue derives from epicardial progenitors635Caloric restriction ameliorates cardiac function, sympathetic cardiac innervation and beta-adrenergic receptor signaling in an experimental model of post-ischemic heart failure636High fat diet improves cardiac remodelling and function after extensive myocardial infarction in mice637Epigenetic therapy reduces cardiac hypertrophy in murine models of heart failure638Imbalance of the VHL/HIF signaling in WT1+ Epicardial Progenitors results in coronary vascular defects, fibrosis and cardiac hypertrophy639Diastolic dysfunction is the first stage of the developing heart failure640Colchicine aggravates coxsackievirus B3 infection in miceArterial and pulmonary hypertension642Osteopontin as a marker of pulmonary hypertension in patients with coronary heart disease combined with chronic obstructive pulmonary disease643Myocardial dynamic stiffness is increased in experimental pulmonary hypertension partly due to incomplete relaxation644Hypotensive effect of quercetin is possibly mediated by down-regulation of immunotroteasome subunits in aorta of spontaneously hypertensive rats645Urocortin-2 improves right ventricular function and attenuates experimental pulmonary arterial hypertension646A preclinical evaluation of the anti-hypertensive properties of an aqueous extract of Agathosma (Buchu)Biomarkers648The adiponectin level in hypertensive females with rheumatoid arthritis and its relationship with subclinical atherosclerosis649Markers for identification of renal dysfunction in the patients with chronic heart failure650cardio-hepatic syndromes in chronic heart failure: North Africa profile651To study other biomarkers that assess during myocardial infarction652Interconnections of apelin levels with parameters of lipid metabolism in hypertension patients653Plasma proteomics in hypertension: prediction and follow-up of albuminuria during chronic renin-angiotensin system suppression654Soluble RAGE levels in plasma of patients with cerebrovascular events. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Al Ali A, Parekh KA, Qureshi A, Jayaprakash P, Adeghate E, Howarth FC, Adrian TE. Induced nitric oxide synthase and diabetic cardiomyopathy. HAMDAN MEDICAL JOURNAL 2015. [DOI: 10.7707/hmj.528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Howarth FC, El Nebrisi E, Jayaprakash P, Qureshi MA, Parekh K, Oz M, Adrian TE. P400Effects of a sucrose-enriched diet on the pattern of gene expression, contraction and Ca2+ transport in Goto-Kakizaki type 2 diabetic rat heart. Cardiovasc Res 2014. [DOI: 10.1093/cvr/cvu091.82] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Gaber EM, Jayaprakash P, Qureshi MA, Parekh K, Oz M, Adrian TE, Howarth FC. Effects of a sucrose-enriched diet on the pattern of gene expression, contraction and Ca(2+) transport in Goto-Kakizaki type 2 diabetic rat heart. Exp Physiol 2014; 99:881-93. [PMID: 24681897 DOI: 10.1113/expphysiol.2013.077594] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus (T2DM), and cardiovascular disease is the major cause of morbidity and mortality in diabetic patients. A variety of diastolic and systolic dysfunctions have been demonstrated in type 2 diabetic heart. The consumption of sugar-sweetened beverages has been linked to rising rates of obesity, which in turn is a risk factor for development of T2DM. In this study, the effects of a sucrose-enriched diet on the pattern of gene expression, contraction and Ca(2+) transport in the Goto-Kakizaki T2DM rat heart were investigated. Genes encoding cardiac muscle proteins (Myh7, Mybpc3, Myl1, Myl3 and Mylpf), intercellular proteins (Gja4), cell membrane transport (Atp1b1), calcium channels (Cacna1c, Cacna1g and Cacnb1) and potassium channels (Kcnj11) were upregulated and genes encoding potassium channels (Kcnb1) were downregulated in GK compared with control rats. Genes encoding cardiac muscle proteins (Myh6, Mybpc3 and Tnn2), intercellular proteins (Gja1 and Gja4), intracellular Ca(2+) transport (Atp2a1 and Ryr2), cell membrane transport (Atp1a2 and Atp1b1) and potassium channel proteins (Kcnj2 and Kcnj8) were upregulated and genes encoding cardiac muscle proteins (Myh7) were downregulated in control rats fed sucrose compared with control rats. Genes encoding cardiac muscle proteins (Myh7) and potassium channel proteins (Kcnj11) were downregulated in control and GK rats fed sucrose compared with control and GK rats, respectively. The amplitude of shortening was reduced in myocytes from the control-sucrose group compared with control rats and in the GK-sucrose group compared with GK rats. The amplitude of the Ca(2+) transient was increased in myocytes from control-sucrose compared with control rats and decreased in GK-sucrose compared with GK rats. Subtle alterations in the pattern of expression of genes encoding a variety of cardiac muscle proteins are associated with changes in shortening and intracellular Ca(2+) transport in ventricular myocytes from GK T2DM and control rats fed a sucrose-enriched diet.
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Affiliation(s)
- E M Gaber
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - P Jayaprakash
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - M A Qureshi
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - K Parekh
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - M Oz
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - T E Adrian
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - F C Howarth
- Department of Physiology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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Al Shemaili J, Mensah-Brown E, Parekh K, Thomas SA, Attoub S, Hellman B, Nyberg F, Adem A, Collin P, Adrian TE. Frondoside A enhances the antiproliferative effects of gemcitabine in pancreatic cancer. Eur J Cancer 2014; 50:1391-8. [PMID: 24462376 DOI: 10.1016/j.ejca.2014.01.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 10/28/2013] [Accepted: 01/06/2014] [Indexed: 01/05/2023]
Abstract
Pancreatic cancer has a very poor prognosis. While gemcitabine is the mainstay of therapy and improves quality of life, it has little impact on survival. More effective treatments are desperately needed for this disease. Frondoside A is a triterpenoid glycoside isolated from the Atlantic sea cucumber, Cucumaria frondosa. Frondoside A potently inhibits pancreatic cancer cell growth and induces apoptosis in vitro and in vivo. The aim of the present study was to investigate whether frondoside A could enhance the anti-cancer effects of gemcitabine. Effects of frondoside A and gemcitabine alone and in combination on proliferation were investigated in two human pancreatic cancer cell lines, AsPC-1 and S2013. To investigate possible synergistic effects, combinations of low concentrations of the two drugs were used for a 72 h treatment period in vitro. Growth inhibition was significantly greater with the drug combinations than their additive effects. Combinations of frondoside A and gemcitabine were tested in vivo using the athymic mouse model. Xenografts of AsPC-1 and S2013 cells were allowed to form tumours prior to treatment with the drugs alone or in combination for 30 days. Tumours grew rapidly in placebo-treated animals. Tumour growth was significantly reduced in all treatment groups. At the lowest dose tested, gemcitabine (4 mg/kg/dose), combined with frondoside A (100 μg/kg/day) was significantly more effective than with either drug alone. To conclude: The present data suggest that combinations of frondoside A and gemcitabine may provide clinical benefit for patients with pancreatic cancer.
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Affiliation(s)
- J Al Shemaili
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; Department of Pharmaceutical Biosciences, Uppsala University, Sweden
| | - E Mensah-Brown
- Department of Anatomy, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - K Parekh
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - S A Thomas
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - S Attoub
- Department of Pharmacology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - B Hellman
- Department of Pharmaceutical Biosciences, Uppsala University, Sweden
| | - F Nyberg
- Department of Pharmaceutical Biosciences, Uppsala University, Sweden
| | - A Adem
- Department of Pharmacology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - P Collin
- Coastside Bio Resources, Stonington, Maine, USA
| | - T E Adrian
- Department of Physiology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.
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9
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Salem KA, Qureshi MA, Sydorenko V, Parekh K, Jayaprakash P, Iqbal T, Singh J, Oz M, Adrian TE, Howarth FC. Effects of exercise training on excitation-contraction coupling and related mRNA expression in hearts of Goto-Kakizaki type 2 diabetic rats. Mol Cell Biochem 2013; 380:83-96. [PMID: 23620341 DOI: 10.1007/s11010-013-1662-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/17/2013] [Indexed: 10/26/2022]
Abstract
Although, several novel forms of intervention aiming at newly identified therapeutic targets are currently being developed for diabetes mellitus (DM), it is well established that physical exercise continues to be one of the most valuable forms of non-pharmacological therapy. The aim of the study was to investigate the effects of exercise training on excitation-contraction coupling and related gene expression in the Goto-Kakizaki (GK) type 2 diabetic rat heart and whether exercise is able to reverse diabetes-induced changes in excitation-contraction coupling and gene expression. Experiments were performed in GK and control rats aged 10-11 months following 2-3 months of treadmill exercise training. Shortening, [Ca(2+)]i and L-type Ca(2+) current were measured in ventricular myocytes with video edge detection, fluorescence photometry and whole cell patch clamp techniques, respectively. Expression of mRNA was assessed in ventricular muscle with real-time RT-PCR. Amplitude of shortening, Ca(2+) transients and L-type Ca(2+) current were not significantly altered in ventricular myocytes from GK sedentary compared to control sedentary rats or by exercise training. Expression of mRNA encoding Tpm2, Gja4, Atp1b1, Cacna1g, Cacnb2, Hcn2, Kcna3 and Kcne1 were up-regulated and Gja1, Kcnj2 and Kcnk3 were down-regulated in hearts of sedentary GK rats compared to sedentary controls. Gja1, Cav3 and Kcnk3 were up-regulated and Hcn2 was down-regulated in hearts of exercise trained GK compared to sedentary GK controls. Ventricular myocyte shortening and Ca(2+) transport were generally well preserved despite alterations in the profile of expression of mRNA encoding a variety of cardiac muscle proteins in the adult exercise trained GK diabetic rat heart.
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Affiliation(s)
- K A Salem
- Department of Pharmacology, College of Medicine & Health Sciences, United Arab Emirates University, Al Ain, UAE
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10
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Adrian TE, Gariballa S, Parekh KA, Thomas SA, Saadi H, Al Kaabi J, Nagelkerke N, Gedulin B, Young AA. Rectal taurocholate increases L cell and insulin secretion, and decreases blood glucose and food intake in obese type 2 diabetic volunteers. Diabetologia 2012; 55:2343-7. [PMID: 22696033 DOI: 10.1007/s00125-012-2593-2] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Accepted: 04/25/2012] [Indexed: 12/17/2022]
Abstract
AIMS/HYPOTHESIS Glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) are secreted from enteroendocrine L cells in response to numerous stimuli, including bile salts. Both have multiple effects that are potentially useful in treating diabetes and obesity. L cell number and hormone content in the intestine are highest in the rectum in humans. We investigated the effects of intrarectal sodium taurocholate on plasma GLP-1, PYY, insulin and glucose concentrations, and on food intake of a subsequent meal. METHODS Ten obese type 2 diabetic volunteers were each studied on five separate occasions after an overnight fast and oral administration of 100 mg sitagliptin 10 h before the study. They then received an intrarectal infusion of either one of four doses of taurocholate (0.66, 2, 6.66 or 20 mmol, each in 20 ml of vehicle) or vehicle alone (1% carboxymethyl cellulose) single-blind over 1 min. Hormone and glucose measurements were made prior to, and for 1 h following, the infusion. The consumption of a previously selected favourite meal eaten to satiety was measured 75 min after the infusion. RESULTS Taurocholate dose-dependently increased GLP-1, PYY and insulin, with 20 mmol doses resulting in peak concentrations 7.2-, 4.2- and 2.6-fold higher, respectively, than those achieved with placebo (p < 0.0001 for each). Plasma glucose decreased by up to 3.8 mmol/l (p < 0.001). Energy intake was decreased dose-dependently by up to 47% (p < 0.0001). The ED(50) values for effects on integrated GLP-1, insulin, PYY, food intake and glucose-lowering responses were 8.1, 10.5, 18.5, 24.2 and 25.1 mmol, respectively. CONCLUSIONS/INTERPRETATION Therapies that increase bile salts (or their mimics) in the distal bowel may be valuable in the treatment of type 2 diabetes and obesity.
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Affiliation(s)
- T E Adrian
- Department of Physiology, Faculty of Medicine and Health Sciences, United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.
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11
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Salem KA, Adrian TE, Qureshi MA, Parekh K, Oz M, Howarth FC. Shortening and intracellular Ca2+ in ventricular myocytes and expression of genes encoding cardiac muscle proteins in early onset type 2 diabetic Goto-Kakizaki rats. Exp Physiol 2012; 97:1281-91. [PMID: 22581745 DOI: 10.1113/expphysiol.2012.066639] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus. Cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. Contractile dysfunction, associated with disturbances in excitation-contraction coupling, has been widely demonstrated in the diabetic heart. The aim of this study was to investigate the pattern of cardiac muscle genes that are involved in the process of excitation-contraction coupling in the hearts of early onset (8-10 weeks of age) type 2 diabetic Goto-Kakizaki (GK) rats. Gene expression was assessed in ventricular muscle with real-time RT-PCR; shortening and intracellular Ca(2+) were measured in ventricular myocytes with video edge detection and fluorescence photometry, respectively. The general characteristics of the GK rats included elevated fasting and non-fasting blood glucose and blood glucose at 120 min following a glucose challenge. Expression of genes encoding cardiac muscle proteins (Myh6/7, Mybpc3, Myl1/3, Actc1, Tnni3, Tnn2, Tpm1/2/4 and Dbi) and intercellular proteins (Gja1/4/5/7, Dsp and Cav1/3) were unaltered in GK ventricle compared with control ventricle. The expression of genes encoding some membrane pumps and exchange proteins was unaltered (Atp1a1/2, Atp1b1 and Slc8a1), whilst others were either upregulated (Atp1a3, relative expression 2.61 ± 0.69 versus 0.84 ± 0.23) or downregulated (Slc9a1, 0.62 ± 0.07 versus 1.08 ± 0.08) in GK ventricle compared with control ventricle. The expression of genes encoding some calcium (Cacna1c/1g, Cacna2d1/2d2 and Cacnb1/b2), sodium (Scn5a) and potassium channels (Kcna3/5, Kcnj3/5/8/11/12, Kchip2, Kcnab1, Kcnb1, Kcnd1/2/3, Kcne1/4, Kcnq1, Kcng2, Kcnh2, Kcnk3 and Kcnn2) were unaltered, whilst others were either upregulated (Cacna1h, 0.95 ± 0.16 versus 0.47 ± 0.09; Scn1b, 1.84 ± 0.16 versus 1.11 ± 0.11; and Hcn2, 1.55 ± 0.15 versus 1.03 ± 0.08) or downregulated (Hcn4, 0.16 ± 0.03 versus 0.37 ± 0.08; Kcna2, 0.35 ± 0.03 versus 0.80 ± 0.11; Kcna4, 0.79 ± 0.25 versus 1.90 ± 0.26; and Kcnj2, 0.52 ± 0.07 versus 0.78 ± 0.08) in GK ventricle compared with control ventricle. The amplitude of ventricular myocyte shortening and the intracellular Ca(2+) transient were unaltered; however, the time-to-peak shortening was prolonged and time-to-half decay of the Ca(2+) transient was shortened in GK myocytes compared with control myocytes. The results of this study demonstrate changes in expression of genes encoding various excitation-contraction coupling proteins that are associated with disturbances in myocyte shortening and intracellular Ca(2+) transport.
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Affiliation(s)
- K A Salem
- Department of Physiology, Faculty of Medicine & Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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12
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Howarth FC, Qureshi MA, Hassan Z, Isaev D, Parekh K, John A, Oz M, Raza H, Adeghate E, Adrian TE. Contractility of ventricular myocytes is well preserved despite altered mechanisms of Ca2+ transport and a changing pattern of mRNA in aged type 2 Zucker diabetic fatty rat heart. Mol Cell Biochem 2011; 361:267-80. [PMID: 22009485 DOI: 10.1007/s11010-011-1112-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2011] [Accepted: 10/07/2011] [Indexed: 02/07/2023]
Abstract
There has been a spectacular rise in the global prevalence of type 2 diabetes mellitus and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The objective of the study was to investigate ventricular myocyte shortening, intracellular Ca(2+) signalling and expression of genes encoding cardiac muscle proteins in the aged Zucker diabetic fatty (ZDF) rat. There was a fourfold elevation in non-fasting blood glucose in ZDF rats (478.43 ± 29.22 mg/dl) compared to controls (108.22 ± 2.52 mg/dl). Amplitude of shortening, time to peak (TPK) and time to half (THALF) relaxation of shortening were unaltered in ZDF myocytes compared to age-matched controls. Amplitude and THALF decay of the Ca(2+) transient were unaltered; however, TPK Ca(2+) transient was prolonged in ZDF myocytes (70.0 ± 3.2 ms) compared to controls (58.4 ± 2.3 ms). Amplitude of the L-type Ca(2+) current was reduced across a wide range of test potentials (-30 to +40 mV) in ZDF myocytes compared to controls. Sarcoplasmic reticulum Ca(2+) content was unaltered in ZDF myocytes compared to controls. Expression of genes encoding cardiac muscle proteins, membrane Ca(2+) channels, and cell membrane ion transport and intracellular Ca(2+) transport proteins were variously altered. Myh6, Tnnt2, Cacna2d3, Slc9a1, and Atp2a2 were downregulated while Myl2, Cacna1g, Cacna1h, and Atp2a1 were upregulated in ZDF ventricle compared to controls. The results of this study have demonstrated that preserved ventricular myocyte shortening is associated with altered mechanisms of Ca(2+) transport and a changing pattern of genes encoding a variety of Ca(2+) signalling and cardiac muscle proteins in aged ZDF rat.
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Affiliation(s)
- F C Howarth
- Department of Physiology, Faculty of Medicine & Health Sciences, United Arab Emirates University, Al Ain, UAE.
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13
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Howarth FC, Qureshi MA, Hassan Z, Al Kury LT, Isaev D, Parekh K, Yammahi SRKD, Oz M, Adrian TE, Adeghate E. Changing pattern of gene expression is associated with ventricular myocyte dysfunction and altered mechanisms of Ca2+ signalling in young type 2 Zucker diabetic fatty rat heart. Exp Physiol 2011; 96:325-37. [PMID: 21216827 DOI: 10.1113/expphysiol.2010.055574] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The association between type 2 diabetes and obesity is very strong, and cardiovascular complications are the major cause of morbidity and mortality in diabetic patients. The aim of this study was to investigate early changes in the pattern of genes encoding cardiac muscle regulatory proteins and associated changes in ventricular myocyte contraction and Ca(2+) transport in young (9- to 13-week-old) type 2 Zucker diabetic fatty (ZDF) rats. The amplitude of myocyte shortening was unaltered; however, time-to-peak shortening and time to half-relaxation of shortening were prolonged in ZDF myocytes (163 ± 5 and 127 ± 7 ms, respectively) compared with age-matched control rats (136 ± 5 and 103 ± 4 ms, respectively). The amplitude of the Ca(2+) transient was unaltered; however, time-to-peak Ca(2+) transient was prolonged in ZDF myocytes (66.9 ± 2.6 ms) compared with control myocytes (57.6 ± 2.3 ms). The L-type Ca(2+) current was reduced, and inactivation was prolonged over a range of test potentials in ZDF myocytes. At 0 mV, the density of L-type Ca(2+) current was 1.19 ± 0.28 pA pF(-1) in ZDF myocytes compared with 2.42 ± 0.40 pA pF(-1) in control myocytes. Sarcoplasmic reticulum Ca(2+) content, release and uptake and myofilament sensitivity to Ca(2+) were unaltered in ZDF myocytes compared with control myocytes. Expression of genes encoding various L-type Ca(2+) channel proteins (Cacna1c, Cacna1g, Cacna1h and Cacna2d1) and cardiac muscle proteins (Myh7) were upregulated, and genes encoding intracellular Ca(2+) transport regulatory proteins (Atp2a2 and Calm1) and some cardiac muscle proteins (Myh6, Myl2, Actc1, Tnni3, Tnn2, and Tnnc1) were downregulated in ZDF heart compared with control heart. A change in the expression of genes encoding myosin heavy chain and L-type Ca(2+) channel proteins might partly underlie alterations in the time course of contraction and Ca(2+) transients in ventricular myocytes from ZDF rats.
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Affiliation(s)
- F C Howarth
- Department of Physiology, Faculty of Medicine & Health Sciences, United Arab Emirates University, PO Box 17666, Al Ain, UAE.
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Li X, Roginsky AB, Ding XZ, Woodward C, Collin P, Newman RA, Bell, Jr RH, Adrian TE. Review of the Apoptosis Pathways in Pancreatic Cancer and the Anti-apoptotic Effects of the Novel Sea Cucumber Compound, Frondoside A. Ann N Y Acad Sci 2008; 1138:181-98. [DOI: 10.1196/annals.1414.025] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Abstract
Pancreatic cancer cells are resistant to the growth-inhibitory and apoptosis-inducing effects of conventional chemotherapeutic agents. There are multiple genetic and epigenetic events during the process of carcinogenesis that enable the cancer cells to avoid normal growth constraints and apoptosis. Investigation of the mechanisms involved has led to multiple strategies that encourage cell death and apoptosis to occur. The pathways involved are summarized in this review, together with some recently developed strategies to promote cell death in this cancer.
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Affiliation(s)
- T E Adrian
- Department of Physiology, Faculty of Medicine and Health Sciences, United Arab Emirates University, POBox 17666, Al Ain, United Arab Emirates.
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16
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Abstract
Severe or chronic disease can lead to cachexia which involves weight loss and muscle wasting. Cancer cachexia contributes significantly to disease morbidity and mortality. Multiple studies have shown that the metabolic changes that occur with cancer cachexia are unique compared to that of starvation. Specifically, cancer patients seem to lose a larger proportion of skeletal muscle mass. There are three pathways that contribute to muscle protein degradation: the lysosomal system, cytosolic proteases and the ubiquitin (Ub)-proteasome pathway. The Ub-proteasome pathway seems to account for the majority of skeletal muscle degradation in cancer cachexia and is stimulated by several cytokines including tumor necrosis factor-alpha, interleukin-1beta, interleukin-6, interferon-gamma and proteolysis-inducing factor. Cachexia is particularly severe in pancreatic cancer and contributes significantly to the quality of life and mortality of these patients. Several factors contribute to weight loss in these patients, including alimentary obstruction, pain, depression, side effects of therapy and a high catabolic state. Although no single agent has proven to halt cachexia in these patients there has been some progress in the areas of nutrition with supplementation and pharmacological agents such as megesterol acetate, steroids and experimental trials targeting cytokines that stimulate the Ub-proteasome pathway.
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Affiliation(s)
- L G Melstrom
- Department of Surgery and Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Feinberg School of Medicine, Chicago, Illinois, USA
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17
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Abstract
Pancreatic cancer is a devastating disease characterized by a dismal prognosis with most patients dying within six months after diagnosis. Surgery is an option in less than one in five of these patients, and even with tumor resection the majority of patients succumb to the disease. Other effective treatment options are not available. Common features of pancreatic cancer are severe cachexia, marked insulin resistance and diabetes mellitus. Several studies have demonstrated connections between pancreatic cancers and the endocrine pancreas and this has raised questions regarding the role of the islets of Langerhans in pancreatic adenocarcinoma. This manuscript reviews the recent literature in this field and addresses several questions regarding the interaction between the islets of Langerhans and pancreatic cancer. This review considers the histological findings in pancreatic cancer, cell culture and animal experiments, the four islet cell types and the hormones they secrete, as well as the influence of the arachidonic acid pathways on islet cell function and pancreatic cancer. While pancreatic adenocarcinomas are ductal in nature, the cell of origin has not been identified and there is even some evidence that the islets may harbor the precursor cell. Considerable evidence suggests that the diabetes is caused by the tumor, while other studies have identified diabetes as a risk factor. Clearly, the islets are important in many aspects of this disease. However, even though progress has been made, some questions regarding the interaction of pancreatic cancer and the endocrine pancreas remain unanswered.
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Affiliation(s)
- R Hennig
- Department of Surgery, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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18
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Abstract
Pancreatic adenocarcinoma is characterized by poor prognosis, late diagnosis and lack of response to conventional therapies. The incidence of this disease shows no sign of declining in the Western world. Thus, new targets need to be identified for pancreatic cancer treatment. In particular, new chemotherapeutic agents would be extremely beneficial for control of unresectable cancer and metastatic lesions as well as for prevention of this deadly disease. Mounting evidence suggests that both lipoxygenases (LOXs) and cyclooxygenases (COXs), the key enzymes for arachidonic acid metabolism, have a profound influence on the development and progression of several human cancers. Recent evidence suggests that both COX and LOX pathways are important in pancreatic cancer. Results from immunocytochemical, RT-PCR, and Western blotting studies have shown that COX, specifically COX-2, is upregulated in human pancreatic cancer cell lines as well as human pancreatic cancer tissues compared with normal ductal cells and normal pancreas specimens. Agents that block COX enzymes significantly inhibit pancreatic cancer growth both in vitro and in vivo, in parallel with induction of apoptosis. Expression of both 5-LOX and 12-LOX is also seen in pancreatic cancer, although compared to the expression of COX this has not been extensively investigated. Chemical inhibitors or antisense oligonucleotides that block either 5-LOX or 12-LOX cause marked inhibition of pancreatic cancer cell proliferation. On the other hand, LOX metabolites stimulate growth of the tumor cells and reverse LOX-inhibitor-induced growth inhibition, suggesting the specific role of LOX in regulating pancreatic cancer cell proliferation. Although questions still need to be answered, such as the underlying mechanisms for COX and LOX-induced growth inhibition, both COX and LOX pathways are potential targets for pancreatic cancer treatment and chemoprevention. COX and LOX enzyme inhibitors are available and have been shown to be relatively safe in the treatment of other diseases.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, 2500 California Plaza, Omaha, NE 68178, USA
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19
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Ding XZ, Tong WG, Adrian TE. 12-lipoxygenase metabolite 12(S)-HETE stimulates human pancreatic cancer cell proliferation via protein tyrosine phosphorylation and ERK activation. Int J Cancer 2001; 94:630-6. [PMID: 11745456 DOI: 10.1002/ijc.1527] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We previously reported that inhibition of the 12-lipoxygenase pathway abolished proliferation and induced apoptosis in several pancreatic cancer cell lines. Furthermore, the 12-lipoxygenase product 12(S)-HETE stimulated pancreatic cancer cell proliferation and reversed 12-lipoxygenase inhibitor-induced growth inhibition. We investigated the underlying mechanism for 12(S)-HETE-induced pancreatic cancer cell proliferation, using 2 human pancreatic cancer cell lines, PANC-1 and HPAF. Cell proliferation was monitored by both thymidine incorporation and cell number. Western blotting was used to investigate the effect of 12(S)-HETE on cellular protein tyrosine phosphorylation as well as ERK, P38 MAPK and JNK/SAPK phosphorylation. 12(S)-HETE markedly stimulated proliferation of pancreatic cancer cells in a time- and concentration-dependent manner. In parallel, 12(S)-HETE induced tyrosine phosphorylation of multiple cellular proteins, while inhibition of tyrosine kinase by genestein abolished 12(S)-HETE-induced proliferation, indicating that intracellular protein tyrosine kinase activation is involved in the mitogenic effects of 12(S)-HETE. Following treatment with 12(S)-HETE, both ERK and P38 MAPK, but not JNK/SAPK, were phosphorylated. The specific MEK inhibitors PD098059 and U0126, which in turn suppress ERK, abolished 12(S)-HETE-stimulated proliferation. In contrast, inhibition of P38 MAPK with SB203580 did not affect 12(S)-HETE-stimulated pancreatic cancer cell proliferation. Furthermore, 12(S)-HETE-stimulated ERK phosphorylation was inhibited by genestein, indicating that tyrosine phosphorylation is essential for ERK activation. These findings suggest that both ERK and cellular protein tyrosine kinase activation are involved in 12(S)-HETE-induced pancreatic cancer cell proliferation but P38 and JNK/SAPK are not involved in this mitogenic effect.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE, USA
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20
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Abstract
In the Burmese python (Python molurus), the rapid up-regulation of gastrointestinal (GI) function and morphology after feeding, and subsequent down-regulation on completing digestion, are expected to be mediated by GI hormones and neuropeptides. Hence, we examined postfeeding changes in plasma and tissue concentrations of 11 GI hormones and neuropeptides in the python. Circulating levels of cholecystokinin (CCK), glucose-dependent insulinotropic peptide (GIP), glucagon, and neurotensin increase by respective factors of 25-, 6-, 6-, and 3.3-fold within 24 h after feeding. In digesting pythons, the regulatory peptides neurotensin, somatostatin, motilin, and vasoactive intestinal peptide occur largely in the stomach, GIP and glucagon in the pancreas, and CCK and substance P in the small intestine. Tissue concentrations of CCK, GIP, and neurotensin decline with feeding. Tissue distributions and molecular forms (as determined by gel-permeation chromatography) of many python GI peptides are similar or identical to those of their mammalian counterparts. The postfeeding release of GI peptides from tissues, and their concurrent rise in plasma concentrations, suggests that they play a role in regulating python-digestive responses. These large postfeeding responses, and similarities of peptide structure with mammals, make pythons an attractive model for studying GI peptides.
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Affiliation(s)
- S M Secor
- Department of Physiology, University of California School of Medicine, Los Angeles, CA 90095-1751, USA.
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21
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Kollman-Bauerly KA, Thomas DL, Adrian TE, Lien EL, Vanderhoof JA. The role of eicosanoids in the process of adaptation following massive bowel resection in the rat. JPEN J Parenter Enteral Nutr 2001; 25:275-81. [PMID: 11531219 DOI: 10.1177/0148607101025005275] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Long chain polyunsaturated fatty acids (LCPUFAs) such as arachidonic acid (AA) and eicosapentaenoic acid (EPA) stimulate intestinal adaptation. Prostaglandins also enhance intestinal adaptation. The purpose of this study was to determine by which eicosanoid pathway dietary arachidonic acid enhances intestinal adaptation. Cyclo-oxygenase or lipoxygenase were selectively inhibited to determine whether either of them enhanced or inhibited adaptation. METHODS Sixty Sprague-Dawley rats were divided into 2 groups, one receiving an 80% small bowel resection and the other receiving a sham operation. Rats were further divided into groups receiving either a placebo, a general lipoxygenase inhibitor (nordihydroguaiaretic acid [NDGA] at 40 mg/kg per day), or a cyclo-oxygenase-2 inhibitor (Etodolac at 3 mg/kg per day). Rats were pair-fed a diet containing 30% kcal from fat, primarily consisting of AA. RESULTS After 14 days, mucosal mass, protein, DNA, and disaccharidase activity were measured in the remaining small intestine. There was a significant decrease in ileal mucosal mass in rats receiving Etodolac and a significant increase in mucosal mass in the duodenum in rats receiving NDGA (both p < .001). Mucosal DNA, protein, and disaccharidase data showed similar trends. CONCLUSIONS These findings suggest that after small bowel resection, dietary arachidonic acid may facilitate the adaptation process by acting as a substrate for the synthesis of prostaglandins, and not through the derivatives of lipoxygenase such as leukotrienes or thromboxanes.
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Affiliation(s)
- K A Kollman-Bauerly
- Department of Pediatrics, University of Nebraska Medical Center/Creighton University, Omaha, USA
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22
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Abstract
It has been established that ductal cells or precursor cells within the ductal tree of the pancreas can differentiate into islet cells. Although islet cells can also form exocrine cells, it is unclear whether they arise from precursor (stem) cells or from mature endocrine cells by transdifferentiation. Using a defined culture medium and technique for islet purification, for the first time we were able to maintain human islets in culture for more than a year. Multilabeling immunohistochemical and immunoelectron microscopic examination of the islets at different days of culture using islet cell markers (antibodies to hormones, neuron-specific enolase, chromogranin A) and ductal cell markers (cytokeratins 7 and 19, carbonic anhydrase II, DU-PAN2, CA 19-9, and MUC1) revealed that endocrine cells gradually transdifferentiate to ductal, acinar, and intermediary cells. Although islet hormone secretion ceased after day 28 in culture, endocrine cells were still detectable at day 60. However, later, all endocrine and exocrine cells were replaced by undifferentiated cells that expressed neuron-specific enolase, chromogranin A, laminin, vimentin, cytokeratin 7 and 19, alpha-1-antitrypsin, transforming growth factor-alpha, and epidermal growth factor receptor. Our data thus show that, under proper conditions, human islets can be maintained in vitro over a long period and that, in the culture condition, islet cells seem to transdifferentiate to exocrine cells and undifferentiated cells, which may be considered pancreatic precursor (stem) cells.
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Affiliation(s)
- B M Schmied
- Eppley Cancer Center, University of Nebraska Medical Center, Omaha 68198-6805, USA
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23
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Kern S, Hruban R, Hollingsworth MA, Brand R, Adrian TE, Jaffee E, Tempero MA. A white paper: the product of a pancreas cancer think tank. Cancer Res 2001; 61:4923-32. [PMID: 11406572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- S Kern
- Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland, USA
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24
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Ternent CA, Thorson AG, Blatchford GJ, Christensen MA, Thompson JS, Lanspa SJ, Adrian TE. Mouth to pouch transit after restorative proctocolectomy: hydrogen breath analysis correlates with scintigraphy. Am J Gastroenterol 2001; 96:1460-3. [PMID: 11374683 DOI: 10.1111/j.1572-0241.2001.03799.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Fast intestinal transit may be responsible for slow adaptation and unacceptable steady-state function after restorative proctocolectomy. Investigation of GI transit time may be valuable in such a setting. We hypothesized that postprandial hydrogen breath tests may yield transit data that correlate with technetium-labeled meal scintigrams. METHODS This study compared intestinal transit after a lactulose and bean meal via the breath hydrogen and scintigraphy methods in 21 ileoanal pouch subjects. The meal consisted of baked beans (425 g), 30 ml (20 g) lactulose syrup, 1 mCi 99mtechnetium sulfur colloid in finely chopped liver and 170 ml tap water. The meal contained 120 Kcal (70% carbohydrate, 18% protein and 12% fat). RESULTS Of 21 pouch subjects, 11 (53%) had breath tests and scintigraphy transit studies that differed by 5-21 min. Three of 21 (14%) scintigraphy mouth to pouch transit times were faster than breath test transits by 43-107 min. Seven of 21 (33%) subjects did not have breath test peaks >10 ppm. Mouth to pouch transit for breath hydrogen (104+/-16 min) and scintigraphy (98+/-7 min) tests had significant correlation (r = 0.96, p < 0.0001) among subjects with alveolar hydrogen peaks and accurate scintigrams (n = 11). Scintigrams were five times more expensive than breath tests. CONCLUSIONS A peaking hydrogen breath test provides an alternative to scintigraphy for estimating intestinal transit after ileoanal pouch.
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Affiliation(s)
- C A Ternent
- Section of Colon and Rectal Surgery, Creighton University School of Medicine, Omaha, Nebraska, USA
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25
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Murphy LO, Cluck MW, Lovas S, Otvös F, Murphy RF, Schally AV, Permert J, Larsson J, Knezetic JA, Adrian TE. Pancreatic cancer cells require an EGF receptor-mediated autocrine pathway for proliferation in serum-free conditions. Br J Cancer 2001; 84:926-35. [PMID: 11286473 PMCID: PMC2363846 DOI: 10.1054/bjoc.2001.1698] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In-vitro and in-vivo studies have shown that autocrine growth factors and receptors are frequently expressed in human malignancies. Few of these studies, however, provide evidence that the identified autocrine pathway is functional. In this study, a functional autocrine growth pathway in pancreatic cancer has been identified using an in-vitro cell culture system. When pancreatic cancer cells were grown without change of medium, proliferation was greater than when either medium was replaced frequently (HPAF, CAPAN-2, PANC-1 or SW1990) or cells were grown in the presence of the EGF receptor tyrosine kinase inhibitor AG1478 or the MEK inhibitor PD098059 (HPAF or CAPAN-2). Activity of extracellular-regulated kinases (ERK) 1 and 2 and c- jun and c- fos mRNA levels were significantly elevated in CAPAN-2 cells cultured continuously in serum-free medium. Collectively, the observations indicate that the EGF receptor and the ERK MAP kinase pathway mediate autocrine signals. In contrast to previous reports, the GRP and IGF-I receptors were shown not to be required for autocrine effects on pancreatic cancer cell proliferation. Autocrine stimulation of the EGF receptor can contribute to sustained mitogenic activity and proliferation of pancreatic cancer cells.
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Affiliation(s)
- L O Murphy
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178, USA
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26
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Murphy LO, Abdel-Wahab YH, Wang QJ, Knezetic JA, Permnert J, Larsson J, Hollingsworth AM, Adrian TE. Receptors and ligands for autocrine growth pathways are up-regulated when pancreatic cancer cells are adapted to serum-free culture. Pancreas 2001; 22:293-8. [PMID: 11291932 DOI: 10.1097/00006676-200104000-00011] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Overexpression of autocrine growth factors and their receptors has been reported in many human cancers. The study of autocrine-regulated pathways using in vitro culture systems can be hindered by the presence of fetal bovine serum in culture medium. A human pancreatic cancer cell line (HPAF) was slowly weaned from its dependence on fetal bovine serum and subsequently maintained in serum-free conditions. Growth factor secretion studies showed that production of autocrine growth factors such as transforming growth factor alpha, gastrin-releasing peptide, and insulin-like growth factor I from weaned cells increased three times compared with nonweaned cells (p < 0.01). The epidermal growth factor and gastrin-releasing peptide receptor densities were also increased in weaned cells (2 times and 2.5 times, respectively, p < 0.05). The proliferation of weaned cells cultured continuously in the same medium was significantly greater than of nonweaned cells (p < 0.05). Collectively, these data indicate that weaned pancreatic cancer cells can proliferate in the absence of serum by up-regulating autocrine pathways.
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Affiliation(s)
- L O Murphy
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178, USA
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27
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Abstract
BACKGROUND AND AIMS Our previous study suggested that the known promotional effect of a high fat diet, which in hamsters induces peripheral insulin resistance, is related to a compensatory proliferation of islet cells. The present study was to examine whether the prevention of islet cell proliferation can inhibit the promotional effect of a high-fat diet in pancreatic carcinogenesis. METHODS Two groups of high fat-fed hamsters were used. One group received Metformin in drinking water for life (HF+Met group), and the other group served as a control (HF group). At the time when the normalization of the plasma insulin level was expected, all hamsters were treated with the pancreatic carcinogen, N-nitrosobis-(2-oxopropyl)amine, and the experiment was terminated 42 weeks later. RESULTS Although 50% of the hamsters in the high-fat group developed malignant lesions, none was found in the HF+Met group (P < 0.05). Also, significantly more hyperplastic and premalignant lesions, most of which were found within the islets, were detected in the high-fat group (8.6 lesions/hamster) than in the HF+Met group (1.8 lesions/hamster). CONCLUSIONS The results lend further support on the significant role of islet cells in pancreatic carcinogenesis and may explain the association between pancreatic cancer and obesity, which is usually associated with peripheral insulin resistance.
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Affiliation(s)
- M B Schneider
- The Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, Nebraska 68198-6805, USA
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Ding XZ, Adrian TE. MEK/ERK-mediated proliferation is negatively regulated by P38 map kinase in the human pancreatic cancer cell line, PANC-1. Biochem Biophys Res Commun 2001; 282:447-53. [PMID: 11401480 DOI: 10.1006/bbrc.2001.4595] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Pancreatic carcinoma is characterized by a poor prognosis and lack of response to conventional therapy. The regulatory mechanisms for the rapid proliferation of pancreatic cancer cells and the particular aggressiveness of this cancer are still not fully understood. In mammalian cells, three MAPK families including ERK, JNK, and P38 MAPK have been characterized. ERK is known to play an important role in regulating pancreatic cancer cell proliferation. However, the role of P38 kinase in pancreatic cancer cell proliferation and its relationship with ERK are unclear. Using the specific P38 inhibitor, SB203580 we found that blockade of P38 MAP kinase significantly enhanced proliferation of the pancreatic cancer cell line, PANC-1 cell, in a concentration-dependent manner. In parallel with the stimulation of proliferation, blockade of P38 MAP kinase markedly induced MEK and ERK1/2 phosphorylation, indicating an interaction between MEK/ERK and P38 MAP kinase signaling. Clearly, the interaction between these kinase pathways does not involve transcription and translation because MEK/ERK was activated immediately upon SB203580 treatment. Furthermore, inhibition of the MEK/ERK cascade using the MEK inhibitor, PD098059 abolished SB203580-induced PANC-1 cell proliferation. From these results, we conclude that a MEK/ERK and P38 MAP kinase interaction is important for pancreatic cancer cell proliferation. Breaking the balance between these two signaling pathways will modify pancreatic cancer cell proliferation.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska
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29
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Permert J, Herrington M, Kazakoff K, Pour PM, Adrian TE. Early changes in islet hormone secretion in the hamster pancreatic cancer model. Teratog Carcinog Mutagen 2001; 21:59-67. [PMID: 11135321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The diabetic state that is seen at a high frequency in association with pancreatic cancer is characterized by elevated plasma levels of several islet hormones and by marked insulin resistance. Both the diabetic state and insulin sensitivity improve after tumor removal by sub-total pancreatectomy. Impaired glucose tolerance has also been found in the hamster pancreatic cancer model, but conflicting data regarding islet function have been reported. In order to further investigate islet function and secretion during early development of pancreatic cancer, we measured the concentrations of insulin, glucagon, somatostatin, and islet amyloid polypeptide (IAPP) in plasma, pancreatic tissue, and secretin-stimulated pancreatic juice at 12 and 27 weeks after the ductal-cell-specific carcinogen, BOP had been used to induce tumors in Syrian golden hamsters. At 12 weeks after BOP, plasma glucagon levels were significantly increased. An exaggerated plasma-glucose response and concomitant hyperinsulinemia were observed at 27 but not 12 weeks after BOP. Plasma IAPP concentrations, but not glucagon or somatostatin, were elevated at 27 weeks. Tissue concentrations of IAPP were substantially reduced in BOP-treated hamsters at 27 weeks. No differences in hormone concentrations were seen in pancreatic juice from the two groups at either of the two time points investigated. The study showed that islet hormone changes accompany the early development of pancreatic tumors in the hamster pancreatic model. The hormone changes and apparent insulin resistance resemble the metabolic changes found in humans with pancreatic cancer.
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Affiliation(s)
- J Permert
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska, USA.
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30
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Strömmer L, Abou El-Ella G, Kamel A, Marcus C, Hager P, Adrian TE, Permert J. Upregulation of uncoupling protein homologues in skeletal muscle but not adipose tissue in posttraumatic insulin resistance. Biochem Biophys Res Commun 2001; 281:334-40. [PMID: 11181051 DOI: 10.1006/bbrc.2001.4360] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Metabolic alterations after surgical stress include peripheral insulin resistance and increased utilization of fat as a fuel substrate. An up-regulation of skeletal muscle uncoupling proteins (UCPs) has been associated with physiologic states of insulin resistance and enhanced fat metabolism in rodents. We examined whether posttraumatic insulin resistance induced the UCPs in gastrocnemius and soleus muscle and white adipose tissue in an experimental model of surgical trauma. Insulin sensitivity was significantly reduced in isolated soleus muscles but unchanged in adipocytes after trauma. In traumatized rats, mRNA and protein contents of UCP2 and UCP3 and were significantly increased in both muscle types. UCP2 protein content in adipose tissue was unaltered by surgical stress. Circulating NEFAs and glycerol were reduced after surgical trauma. We hypothesize that the changes in UCP2 and UCP3 gene and protein expression are involved in the regulation of substrate utilization in posttraumatic insulin resistance.
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Affiliation(s)
- L Strömmer
- Arvid Wretlinds Laboratory for Metabolic, Karolinska Institute at Huddinge University Hospital, Stockholm, Sweden.
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31
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Arnelo U, Herrington MK, Theodorsson E, Adrian TE, Reidelberger R, Larsson J, Marcusson J, Strömmer L, Ding X, Permert J. Effects of long-term infusion of anorexic concentrations of islet amyloid polypeptide on neurotransmitters and neuropeptides in rat brain. Brain Res 2000; 887:391-8. [PMID: 11134629 DOI: 10.1016/s0006-8993(00)03070-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Islet amyloid polypeptide (IAPP or amylin) potently reduces food intake in rats at or near physiological concentrations. Although the mechanisms of action of IAPP are not understood, the brain is a suggested site. Changes in hypothalamic and striatal neurotransmission have been reported following acute systemic administration of a pharmacological concentration of IAPP. In the current study, we evaluated the effects of chronic administration of low doses of IAPP on satiety-related neurotransmitters and neuropeptides in the hypothalamus, hippocampus, striatum, left cortex, and right cortex of the rat. Doses of 0, 5 and 25 pmol IAPP/kg-min were administered subcutaneously for 2 or 5 days. Food intake was reduced by 27 and 44% (both P<0.001) for the 5 and 25 pmol/kg-min groups, respectively, in the 2-day experiment and was decreased by 14% (P<0.01) and 24% (P<0.001), respectively, in the 5-day experiment. Body weight was significantly decreased in a dose-dependent fashion. In the 2-day experiment, norepinephrine increased in the hypothalamus in the 5 pmol IAPP/kg-min group, and neurotensin increased in the hippocampus in the 25 pmol/kg-min rats (both P<0.05). In the 5-day, 5 pmol/kg-min rats, 5-hydroxyindoleacetic acid (5-HIAA) increased in the hypothalmus and cholecystokinin (CCK) increased in the striatum (both P<0.05). In the 5-day, 25 pmol/kg-min group, neuropeptide Y (NPY) increased in the hypothalamus (P<0.01) and CCK increased in the hypothalmus and striatum (both P<0.05). The present study confirms that IAPP is a potent anorectic peptide at low doses and suggests that IAPP not only affects classical neurotransmitters in the brain but also alters concentrations of neuropeptides known to be involved in food intake.
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Affiliation(s)
- U Arnelo
- Arvid Wretlind Laboratory for Metabolic Research, Department of Surgery, Karolinska Institutet at Huddinge University Hospital, S-14186 Stockholm, Sweden.
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32
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Abstract
The long-term maintenance of human islets in culture has remained a challenge. Despite advancements in culture techniques, human islets proved to have a short life span in vitro. For the first time, we have succeeded in maintaining human islets in a defined culture medium for more than 12 months. Freshly isolated islets from a 38-year-old donor were cultured in M3:5 medium and placed on a rocker for 14 days to remove contaminated exocrine and mesenchymal cells which attached to the bottom. The floating islets were purified by daily hand-picking and transfer into fresh medium. After 14 days, purified islets were allowed to attach to the bottom of the flasks and to expand. At various time points, islets were examined immunohistochemically and electron microscopically, and the secretion of islet hormones and their mRNA were determined by radioimmunoassay and reverse transcriptase polymerase chain reaction, respectively. Within seven days of culture, ductular and acinar cells developed within the initially normal islets. With time, exocrine cell types expanded while the number of the endocrine cells and their secretion decreased. At day 60, only a few endocrine cells were identifiable, whereas most of the cells appeared undifferentiated and expressed cytokeratin 7 and 19, neuron specific enolase, tomato lectin, phaseolus leucoagglutinin, laminin, and vimentin. After 60 days, the culture consisted entirely of undifferentiated cells which could be maintained in culture for 270 days before they became senescent. This is the first report on the long-term maintenance of human islet cells in culture and allows an insight into the complex process of endocrine cell differentiation.
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Affiliation(s)
- B M Schmied
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, 986805 Nebraska Medical Center, Omaha, NE 68198-6805, USA
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Abstract
Cultivation and preservation of human pancreatic ductal cells have remained a challenge. With a defined culture medium and refinement of culturing techniques, we have been able to maintain human pancreatic ductal cells without any genetic manipulation in culture for more than 16 months. Freshly isolated ductal fragments were placed on a rocker in M3:5 medium free of collagen for 14 days to remove fibroblasts and endocrine cells before allowing them to attach. The cells produced an excessive amount of mucin and expressed the duct specific cytokeratins (CK) 7 and 19, DU-PAN2, CA19-9, carbonic anhydrase II (CA II), and secretin receptors. During the course of the culture, however, the cells gradually lost the expression of CA II, secretin receptors, DU-PAN2, and CA 19-9 and assumed an undifferentiated phenotype, which showed an upregulation of transforming growth factor alpha (TGFalpha) and epidermal growth factor receptor (EGFR), an increase in the expression of Ki-67, and an increased binding to Phaseolus vulgaris leucoagglutinin (PHA-L) and tomato lectin. These ductal cells present a useful source with which to study physiologic aspects of ductal cells including differentiation.
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Affiliation(s)
- A B Ulrich
- UNMC Eppley Cancer Center, Omaha 68198-6805, USA
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Leinsköld T, Adrian TE, Arnelo U, Larsson J, Permert J. Gastrointestinal growth factors and pancreatic islet hormones during postoperative IGF-I supplementation in man. J Endocrinol 2000; 167:331-8. [PMID: 11054648 DOI: 10.1677/joe.0.1670331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Insulin-like growth factor-I (IGF-I) has been demonstrated to exert a nitrogen sparing effect, both experimentally and in patients after abdominal surgery. IGF-I is a major mediator for the anabolic effects of growth hormone (GH). Whether elevated circulating IGF-I levels are the sole mediator of the anabolic effects following GH has not been clarified. IGF-I influences glucose metabolism, both through its own specific receptor and by activating the insulin receptor, and has also been proposed to influence pancreatic islet secretion directly. In the present study, the postoperative effects of IGF-I on plasma levels of other gastrointestinal and pancreatic islet hormones and growth factors were measured in patients after abdominal surgery. Fifteen patients who were candidates for large bowel resection were randomly divided into two groups: IGF-I-treated (n=8) and placebo-treated (n=7). The IGF-I group received daily two s.c. injections of human recombinant IGF-I (80 microg/kg body weight) for five days, beginning on the morning of the first postoperative day. The other group received placebo injections. Fasting plasma levels of gastrointestinal growth factors (epidermal growth factor, transforming growth factor-alpha, IGF-II), gastrointestinal hormones (gastrin, enteroglucagon, peptide YY), and islet hormones (insulin, islet amyloid polypeptide (IAPP) and pancreatic glucagon) were determined by RIA preoperatively and after five days of treatment. No significant effects of IGF-I on other growth factors or gastrointestinal hormones were seen. A marked increase in plasma insulin postoperatively compared with the preoperative levels (42+/-3 vs 61+/-5 pM, P<0.05) was seen in the placebo group, whereas the postoperative levels in the IGF-I-treated patients remained unchanged (44+/-3 vs 45+/-4 pM). A similar pattern was observed for IAPP and cortisol concentrations. No differences in glucagon concentrations were seen. In conclusion, these results suggest that IGF-I does not influence production of other gastrointestinal hormones thought to be involved in alimentary growth or pancreatic glucagon. In contrast, IGF-I caused a marked reduction of insulin and IAPP secretion. The inhibition of beta-cell secretion could be direct or, alternatively, could involve an improvement in postoperative insulin resistance, perhaps by reducing serum cortisol.
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Affiliation(s)
- T Leinsköld
- Department of Surgery, University of Linköping, Linköping, Sweden
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35
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Herrington MK, Adrian TE. Effects of epidermal growth factor, cholecystokinin, and secretin on growth of the alimentary tract in the neonatal guinea pig. Biol Neonate 2000; 73:129-36. [PMID: 9483306 DOI: 10.1159/000013969] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Gut hormones and growth factors are likely to be involved in the functional changes and substantial growth of the alimentary tract that occurs during early neonatal life. The present experiments investigated the effects of continuous subcutaneous infusion of cholecystokinin (CCK), secretin, and epidermal growth factor (EGF) in neonatal guinea pigs for 4 or 15 days. At doses of 20, 100 or 500 pmol/kg/h, CCK and secretin had no effect on alimentary tract organs except for an increase in pancreatic weight at 4 days with the highest dose of CCK and an increase in stomach weight at 4 days with the highest dose of secretin. In contrast, EGF showed dose-dependent and time-dependent effects on all the alimentary tract organs when infused at 70, 210 and 630 pmol/kg/h. These results suggest that EGF, but not CCK or secretin, is likely to be an important trophic factor during the neonatal period.
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Affiliation(s)
- M K Herrington
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178, USA
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36
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Ding XZ, Fehsenfeld DM, Murphy LO, Permert J, Adrian TE. Physiological concentrations of insulin augment pancreatic cancer cell proliferation and glucose utilization by activating MAP kinase, PI3 kinase and enhancing GLUT-1 expression. Pancreas 2000; 21:310-20. [PMID: 11039477 DOI: 10.1097/00006676-200010000-00014] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Pancreatic carcinoma is characterized by poor prognosis and lack of response to conventional therapy for reasons that are not clear. Because of the structural relationship between the exocrine and endocrine pancreas and high concentrations of islet hormones bathing pancreatic tissue, we hypothesized that pancreatic cancer cell proliferation and glucose utilization are regulated by pancreatic islet hormones, particularly insulin. Based on this, the effect of islet hormones on pancreatic cancer cells in vitro was investigated. Five pancreatic cancer cell lines, CD11, CD18, HPAF, PANC-1, and MiaPaCa2 were used to investigate the effect of islet hormones on cell proliferation, glucose utilization, and GLUT-1 expression. Insulin, but not somatostatin and glucagon, induced pancreatic cancer cell growth in a concentration- and time-dependent manner. At concentrations within the range of those in the intrapancreatic vasculature, insulin (10(-10)-10(-8) mol/L) markedly increased [3H]-thymidine incorporation. Insulin significantly enhanced glucose utilization of pancreatic cancer cells before it enhanced cell proliferation. The MAPK kinase inhibitor PD 098059 abolished insulin-stimulated DNA synthesis and partially reduced insulin-stimulated glucose uptake. In contrast, the PI3 kinase inhibitor wortmannin substantially inhibited insulin-induced glucose uptake and partially blocked thymidine incorporation. Furthermore, after 24-hour treatment with insulin, GLUT-I expression in pancreatic cancer cells was markedly increased, indicating that insulin enhances glucose utilization partly through increasing glucose transport. These findings suggest that insulin stimulates proliferation and glucose utilization in pancreatic cancer cells by two distinct pathways. Insulin augments DNA synthesis mainly by MAP kinase activation and glucose uptake mainly by PI3 kinase activation and enhancement of GLUT-I expression. High intrapancreatic concentrations of insulin are likely to play an important role in stimulating pancreatic cancer growth indirectly by increasing substrate availability as well as by direct action as a trophic factor.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University, School of Medicine, Omaha, Nebraska 68178, USA
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37
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Ding XZ, Tong WG, Adrian TE. Blockade of cyclooxygenase-2 inhibits proliferation and induces apoptosis in human pancreatic cancer cells. Anticancer Res 2000; 20:2625-31. [PMID: 10953335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Cyclooxygenase (COX), also referred to as prostaglandin endoperoxide synthase, is a key enzyme in the conversion of arachidonic acid to prostaglandins and other eicosanoids. Epidemiologic, animal and in vitro observations show a positive correlation between the expression of COX (especially COX-2) and colonic cancer development, growth and apoptosis. Constitutive expression of COX-2 in human pancreatic cancer cells was recently reported. To evaluate the potential role of COX in pancreatic cancer, RT-PCR was used to determine the constitutive expression of COX-2 in four pancreatic cancer cell lines. MiaPaCa2, PANC-1, HPAF, ASPC-1. The effect of COX blockade with either the general COX inhibitor, indomethacin, or the specific COX-2 inhibitor, NS-398, on [3H]-thymidine incorporation and cell number was investigated in these four pancreatic cancer cell lines. In addition, the effects of these COX inhibitors on pancreatic cancer cell apoptosis was evaluated by DNA propidium iodide staining and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay. All four human pancreatic cancer cell lines expressed COX-2 and their proliferation was concentration- and time-dependently inhibited by both indomethacin andNS398. Substantial apoptosis was also induced by treatment of pancreatic cancer cells with either indomethacin or NS398, as indicated by both DNA propidium iodide staining and the TUNEL assay. Furthermore, indomethacin and NS398 were equipotent for growth inhibition and induction of apoptosis, indicating that eicosanoid synthesis via COX-2 is involved in pancreatic cancer cell proliferation and survival. In conclusion, these findings suggest that the COX pathway, especially COX-2, contributes to the growth and apoptosis of pancreatic cancer. Specific COX-2 inhibitors are likely to be valuable for the treatment and prevention of this deadly cancer.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, NE 68178, USA
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Wirén M, Adrian TE, Arnelo U, Permert J, Staab P, Larsson J. Early gastrointestinal regulatory peptide response to intestinal resection in the rat is stimulated by enteral glutamine supplementation. Dig Surg 2000; 16:197-203. [PMID: 10436367 DOI: 10.1159/000018727] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
BACKGROUND Intestinal resection stimulates the synthesis and release of gastrointestinal peptides that regulate the growth and adaptation of the mucosa. Luminal nutrients are necessary for optimal proliferation and glutamine is the preferential nutrient to the small bowel. The interplay between glutamine and regulatory peptides could be important in treating short bowel syndrome. METHODS 63 Sprague-Dawley rats were divided into 3 groups: resection; transection, or controls. After intestinal resection animals were orally fed either a diet without glutamine or a glutamine-supplemented diet for 2 days. Transected animals and controls without prior surgery were fed the same two diets. Epidermal growth factor (EGF), transforming growth factor-alpha, insulin-like growth factors I and II (IGF-I and IGF-II), peptide YY (PYY), and enteroglucagon were analyzed in mucosa from the proximal jejunum, distal ileum as well as in portal plasma when the animals were euthanized 72 h after surgery. RESULTS Intestinal resection resulted in an early increase in portal plasma concentrations of PYY, EGF, enteroglucagon, and mucosal IGF-II and EGF content that were significant in glutamine-treated animals. Glutamine significantly increased PYY in portal blood after resection (p < 0.05). CONCLUSION Glutamine could be of importance for the functional adaptation of residual small bowel mucosa by increasing PYY release.
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Affiliation(s)
- M Wirén
- Department of Surgery, Faculty of Health Sciences, University of Linköping, Sweden.
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Schmied BM, Ulrich AB, Matsuzaki H, El-Metwally TH, Ding X, Fernandes ME, Adrian TE, Chaney WG, Batra SK, Pour PM. Biologic instability of pancreatic cancer xenografts in the nude mouse. Carcinogenesis 2000; 21:1121-7. [PMID: 10836999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
Abstract
Tumor transplants into nude mice (NM) may reveal abnormal biological behavior compared with the original tumor. Despite this, human tumor xenografts in NM have been widely used to study the biology of tumors and to establish diagnostic and therapeutic modalities. Clearly, precise differences in the biology of a given tumor in human and in NM cannot be assessed. We compared the growth kinetics, differentiation pattern and karyotype of an anaplastic Syrian hamster pancreatic cancer cell line in NM and in allogenic hamsters. As with the original tumor, transplants in hamsters grew fast, were anaplastic and expressed markers related to tumor malignancy like galectin 3, TGF-alpha and its receptor EGFR at high levels. However, tumors in the NM were well-differentiated adenocarcinomas, grew slower, had increased apoptotic rate and had a high expression of differentiation markers such as blood group A antigen, DU-PAN-2, carbonic anhydrase II, TGF-beta(2) and mucin. Karyotypically, the tumors in the NM acquired additional chromosomal damage. Our results demonstrate significant differences in the morphology and biology of tumors grown in NM and the allogenic host, and call for caution in extrapolating data obtained from xenografts to primary cancer.
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Affiliation(s)
- B M Schmied
- UNMC Eppley Cancer Center, University of Nebraska Medical Center, Omaha, NE, USA
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Abstract
BACKGROUND Alkaline oesophagitis attributable to duodenal mechanisms may induce oesophageal carcinogenesis in a rat reflux model. AIM To investigate the mechanism of the regurgitation after distal partial gastrectomy. METHODS Oesophageal manometry was used in 16 patients before and after distal partial gastrectomy with reconstruction by Bilroth methods. Serum concentrations of four gastrointestinal hormones were measured by radioimmunoassay in 10 gastrectomy patients and nine healthy volunteers before and after a standardized meal. RESULTS The lower oesophageal sphincter pressure was reduced to 83% after surgery. The amplitude and duration of the peristaltic waves tended to be increased, and the velocity tended to be less after surgery (amplitude 120%, duration 114%, velocity 88%). Interrupted waves appeared more frequently after surgery. The manometric changes in gastrectomized patients are considered to be disadvantageous relative to regurgitation. After surgery, gastrin and pancreatic polypeptide were completely abolished postprandially, whereas cholecystokinin and neurotensin were significantly increased. CONCLUSION The hormonal changes should have a suppressive effect on the lower oesophageal sphincter. Both the manometric and the hormonal changes may exacerbate reflux oesophagitis after distal partial gastrectomy.
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Affiliation(s)
- Y Yamashita
- Department of Surgical Oncology, Research Institute for Radiation Biology & Medicine, Hiroshima University, Japan
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Abstract
The diabetes that frequently occurs in pancreatic cancer patients is characterized by profound peripheral insulin resistance. The intracellular mechanism of this insulin resistance was investigated in skeletal muscle biopsies from pancreatic cancer patients with or without diabetes and control subjects. Insulin receptor (IR) binding, tyrosine kinase activity, IR messenger RNA (mRNA), IR substrate-1 content, GLUT-4, and GLUT-4 mRNA content were all normal in pancreatic cancer patients. In contrast, multiple defects in glycogen synthesis were found in pancreatic cancer patients, especially in those with diabetes. Glycogen synthase I activity, total activity, and mRNA levels were significantly decreased in pancreatic cancer patients compared with controls. The fractional velocity of glycogen synthase was decreased only in the diabetic pancreatic cancer group. Glycogen phosphorylase a and b activities were increased in diabetic pancreatic cancer patients, but glycogen phosphorylase mRNA levels were not significantly different. The insulin resistance associated with pancreatic cancer is associated with a post-IR defect, which impairs skeletal muscle glycogen synthesis and glycogen storage.
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Affiliation(s)
- J Liu
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178, USA
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Schmied BM, Ulrich AB, Matsuzaki H, Li C, Friess H, Böchler MW, Andron-Sandberg A, Adrian TE, Pour PM. Alteration of the Langerhans Islets in Pancreatic Cancer Patients. ACTA ACUST UNITED AC 2000; 28:187-97. [PMID: 11373056 DOI: 10.1385/ijgc:28:3:187] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
An abnormal glucose metabolism occurs in up to 80% of pancreatic cancer patients shortly or a few months before the first clinical admission. Reasons for this abnormality are obscure. We investigated immunohistochemically the pattern of islets in 14 pancreatic cancer specimens and used 14 chronic pancreatitis samples and 10 normal pancreata as controls. To study the topographical relationship of these islets to the cancer, islets in four different arbitrary zones within and around the cancer were evaluated. Ten out of 14 cancer specimens showed a significant loss of beta cells (p < 0.005) and eight of them also showed a significant increase of alpha cells (p < 0.005), all of them from hyperglycemic patients. Most affected islets were found within zone 1 (intratumoral) and zone 2 (peritumoral), to a lesser extent in zone 3 (acini close to tumor) and none in zone 4 (acini remote from tumor). No comparable changes were found in chronic pancreatitis patients. The incidence of 72% with alteration of islets in our material correlates with the frequency of abnormal glucose levels in human pancreatic cancer patients. Our findings support the notion that islet cell abnormalities is likely caused by substances released from cancer cells.
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Affiliation(s)
- B M Schmied
- UNMC Eppley Cancer Center, University of Nebraska Medical Center, Omaha 68198-6805, USA
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Ding XZ, Kuszynski CA, El-Metwally TH, Adrian TE. Lipoxygenase inhibition induced apoptosis, morphological changes, and carbonic anhydrase expression in human pancreatic cancer cells. Biochem Biophys Res Commun 1999; 266:392-9. [PMID: 10600514 DOI: 10.1006/bbrc.1999.1824] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epidemiologic and animal studies have linked pancreatic cancer growth with fat intake, especially unsaturated fats. Arachidonic acid release from membrane phospholipids is essential for tumor cell proliferation. Lipoxygenases (LOX) constitute one pathway for arachidonate metabolism. We previously reported that 5-LOX and 12-LOX are upregulated in human pancreatic cancer cells and that blockade of these enzymes abolishes pancreatic cancer cell growth. The present study was aimed at evaluating the effect of LOX inhibition on differentiation and apoptosis in pancreatic cancer cells in parallel with growth inhibition. Four human pancreatic cancer cell lines, PANC-1, MiaPaca2, Capan2, and HPAF, were used. Apoptosis was evaluated by three separate methods, including DNA propidium iodide staining, DNA fragmentation, and the TUNEL assay. Morphological changes and carbonic anhydrase activity were used to determine the effect of LOX inhibitors on differentiation. The general LOX inhibitor NDGA, the 5-LOX inhibitor Rev5901, and the 12-LOX inhibitor baicalein all induced apoptosis in all four pancreatic cancer cell lines, as confirmed by all three methods, suggesting that both the 5-LOX and 12-LOX pathways are important for survival of these cells. Furthermore, NDGA, Rev5901, or baicalein resulted in marked cellular morphological changes in parallel with increased intracellular carbonic anhydrase activity, indicating that LOX blockade induced a more differentiated phenotype in human pancreatic cancer cells. Together with our previous findings, this study suggests that perturbations of LOX activity affect pancreatic cancer cell proliferation and survival. Blockade of LOX enzymes may be valuable for the treatment of human pancreatic cancer.
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178, USA
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44
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Kleinman RM, Fagan SP, Ray MK, Adrian TE, Wong H, Imagawa D, Walsh JH, Brunicardi FC. Differential inhibition of insulin and islet amyloid polypeptide secretion by intraislet somatostatin in the isolated perfused human pancreas. Pancreas 1999; 19:346-52. [PMID: 10547194 DOI: 10.1097/00006676-199911000-00005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Islet amyloid polypeptide (IAPP) and insulin are co-stored and generally secreted in parallel; however, studies have demonstrated that the IAPP/insulin molar secretory ratio may be altered in response to certain stimuli. Because we previously demonstrated that intraislet somatostatin is an inhibitory regulator of basal insulin secretion in the isolated perfused human pancreas, this study was designed to determine the relative influence on the regulation of IAPP versus insulin secretion. Single-pass perfusion was performed in pancreata obtained from cadaveric organ donors with continuous perfusion of a modified Krebs media with the glucose level maintained at constant 3.9 mM. Intraislet somatostatin was immunoneutralized by the infusion of either a highly sensitive monoclonal somatostatin antibody (SAb) or its FAb fragment (SFAb). Sequential test periods separated by basal periods were performed by infusion of either of the following: glucose, SAb, SFAb, or appropriate controls. IAPP/insulin molar secretory ratio decreased by 33% in response to infusion of either SAb or the SFAb, respectively (p < 0.01), and decreased by 67% in response to glucose infusion (p < 0.01). An alteration of the IAPP/insulin secretory ratio is seen in response to infusion of exogenous glucose or in response to the neutralization of intraislet somatostatin.
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Affiliation(s)
- R M Kleinman
- Department of Surgery, VAMC-West Los Angeles and Department of Surgery, UCLA School of Medicine, California, USA
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45
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Abstract
Epidemiologic and animal studies have linked pancreatic cancer growth with fat intake, especially unsaturated fats. Arachidonic acid release from membrane phospholipids is essential for tumor cell proliferation. Lipoxygenases (LOX) constitute one pathway for arachidonate metabolism, but their role in pancreatic cancer growth is unknown. The expression of 5-LOX and 12-LOX as well as their effects on cell proliferation was investigated in four human pancreatic cancer cell lines (PANC-1, MiaPaca2, Capan2, and ASPC-1). Expression of 5-LOX and 12-LOX mRNA was measured by nested RT-PCR. Effects of LOX inhibitors and specific LOX antisense oligonucleotides on pancreatic cancer cell proliferation were measured by (3)H-thymidine incorporation. Our results showed that (1) 5-LOX and 12-LOX were expressed in all pancreatic cancer cell lines tested, while they were not detectable in normal human pancreatic ductal cells; (2) both LOX inhibitors and LOX antisense markedly inhibited cell proliferation in a concentration-dependent and time-dependent manner; (3) the 5-LOX and 12-LOX metabolites 5-HETE and 12-HETE as well as arachidonic and linoleic acids directly stimulated pancreatic cancer cell proliferation; (4) LOX inhibitor-induced growth inhibition was reversed by 5-HETE and 12-HETE. The current studies indicate that both 5-LOX and 12-LOX expression is upregulated in human pancreatic cancer cells and LOX plays a critical role in pancreatic cancer cell proliferation. LOX inhibitors may be valuable for the treatment of pancreatic cancer.
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MESH Headings
- 12-Hydroxy-5,8,10,14-eicosatetraenoic Acid/pharmacology
- Arachidonate 12-Lipoxygenase/genetics
- Arachidonate 5-Lipoxygenase/genetics
- Arachidonic Acid/pharmacology
- Cell Division/drug effects
- Cells, Cultured
- Dose-Response Relationship, Drug
- Gene Expression Regulation, Neoplastic
- Humans
- Hydroxyeicosatetraenoic Acids/pharmacology
- Linoleic Acid/pharmacology
- Lipoxygenase Inhibitors/pharmacology
- Lipoxygenase Inhibitors/therapeutic use
- Oligonucleotides, Antisense/genetics
- Oligonucleotides, Antisense/metabolism
- Pancreatic Neoplasms/drug therapy
- Pancreatic Neoplasms/enzymology
- Pancreatic Neoplasms/metabolism
- Pancreatic Neoplasms/pathology
- RNA, Messenger/analysis
- RNA, Messenger/genetics
- Time Factors
- Transfection
- Tumor Cells, Cultured
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Affiliation(s)
- X Z Ding
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska, USA
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Abstract
Patients with cancer cachexia exhibit increased glucose flux and lactate production in skeletal muscle. The aim of this study was to examine the direct effect of cancer cell-conditioned media on glucose metabolism in L6 myoblasts. Media from PANC-1 and Colo 320 cells caused a marked time-dependent and concentration-dependent increase of 2-deoxyglucose uptake in GLUT-4 transfected L6 myoblasts. This effect was greater than maximal acute stimulation by insulin and the effect of insulin was additive. Glucose utilization and lactate production increased in parallel to glucose uptake. The effect was inhibited by the protein synthesis inhibitor, cycloheximide and the glucose transport inhibitor, cytochalasin B. The bioactive factor had a molecular weight of approximately 5,000 and the biological activity was destroyed by proteinase K digestion. Radioimmunoassay and immunoneutralization studies indicated the major factor involved is not TNFalpha, IL-1beta, insulin, IGF-I or IGF-II. Further purification and characterization are needed to reveal the identity of this novel factor or factors which may have other metabolic effects that contribute to the cancer cachexia and insulin resistance.
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Affiliation(s)
- J Li
- Department of Biomedical Sciences, Creighton University School of Medicine, 2500 California Plaza, Omaha, Nebraska, 68178, USA
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Wetscher GJ, Hinder RA, Smyrk T, Perdikis G, Adrian TE, Profanter C. Gastric acid blockade with omeprazole promotes gastric carcinogenesis induced by duodenogastric reflux. Dig Dis Sci 1999; 44:1132-5. [PMID: 10389684 DOI: 10.1023/a:1026615905170] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Duodenogastric reflux (DGR) in rats causes growth stimulation of the foregut mucosa that is potentiated by gastric acid blockade. It was the aim of this study to investigate if DGR with gastric acid blockade has a higher incidence of carcinomas of the foregut than DGR alone. DGR was induced in 40 Sprague-Dawley rats using a split gastroenterostomy. A cardiomyotomy was performed across the gastroesophageal junction, inducing reflux into the esophagus. Twenty of these rats received omeprazole postoperatively. After one year 18 rats (90%) with DGR + omeprazole treatment and 7 rats (35%) with DGR alone developed adenocarcinoma of the stomach (P < 0.05). None of the rats developed esophageal cancer, but esophageal mucosal hyperplasia was more pronounced in rats receiving omeprazole. Control rats, treated with omeprazole, did not develop carcinomas of the foregut. In conclusion, gastric acid blockade enhanced DGR-induced carcinogenesis of the stomach and promotes growth stimulation of the esophageal mucosa.
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Affiliation(s)
- G J Wetscher
- Department of Surgery, University of Innsbruck, Austria
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48
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Wang F, Adrian TE, Westermark G, Gasslander T, Permert J. Dissociated insulin and islet amyloid polypeptide secretion from isolated rat pancreatic islets cocultured with human pancreatic adenocarcinoma cells. Pancreas 1999; 18:403-9. [PMID: 10231847 DOI: 10.1097/00006676-199905000-00012] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Abnormal insulin and islet amyloid polypeptide (IAPP) secretion are usually seen in patients with exocrine pancreatic cancer. The beta-cell dysfunction is a characteristic of the glucose intolerance found in pancreatic cancer patients. The effects of pancreatic cancer cells on insulin and IAPP secretion from beta cells are unclear. In this study, isolated rat pancreatic islets were cocultured with two human pancreatic adenocarcinoma cell lines (Panc-1 and HPAF) and a human colonic adenocarcinoma cell line (HT-29). As a control, islets were incubated in the absence of malignant cells. The accumulation of insulin and IAPP in culture media was measured by radioimmunoassay. Output of insulin and IAPP was decreased in islets cocultured with each malignant cell line. Molar ratio of secreted IAPP and insulin (IAPP/insulin) was increased in the islets cocultured with Panc-1 or HPAF cells, but not HT-29 cells. The decreased insulin and IAPP secretion were partly recovered after Panc-1, HPAF, or HT-29 cells were removed. The IAPP/insulin ratio was normalized after the removal of Panc-1 or HPAF cells. This study indicates that insulin and IAPP secretion are altered by the human adenocarcinoma cells investigated. The impairment induced by pancreatic adenocarcinoma cells is associated with a hypersecretion of IAPP relative to insulin on a molar basis.
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Affiliation(s)
- F Wang
- Department of Surgery, Karolinska Institute, Huddinge University Hospital, Sweden
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El-Metwally TH, Adrian TE. Optimization of treatment conditions for studying the anticancer effects of retinoids using pancreatic adenocarcinoma as a model. Biochem Biophys Res Commun 1999; 257:596-603. [PMID: 10198257 DOI: 10.1006/bbrc.1999.0502] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Retinoids are natural differentiation-inducing compounds that are promising as anticancer agents. Cancer cell lines are valuable in the investigation of the potential of retinoids for the treatment of specific cancers. However, using different treatment conditions but the same cell lines, investigators have produced markedly contradictory results for the effectiveness of retinoids. The present study examined different factors in the treatment conditions that may have masked or interfered with the effects of retinoids and, thereby, resulted in this conflict. Our studies revealed that the effects of retinoids on cancer cell proliferation were influenced by serum, the choice of vehicle (DMSO vs ethanol) and its concentration, phenol red, the degree of cellular confluence, and the method of assessing proliferation (cell number or [3H]thymidine uptake vs the MTT assay). Optimized conditions were the use of serum-free, ethanol-free, and phenol red-free media, investigating cells in the log phase of growth, using </=0.01% DMSO as the vehicle, and monitoring proliferation by cell number or [3H]thymidine incorporation into DNA measured after TCA precipitation. Using these conditions, retinoids were found to exhibit potent antiproliferative effects in pancreatic cancer cells with a variety of degrees of differentiation, even in cell lines previously documented as being retinoid resistant. Retinoids also induced morphological changes and cellular death that may indicate terminal differentiation and apoptosis.
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Affiliation(s)
- T H El-Metwally
- Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska, 68154, USA.
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50
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Thompson JS, Quigley EM, Adrian TE. Factors affecting outcome following proximal and distal intestinal resection in the dog: an examination of the relative roles of mucosal adaptation, motility, luminal factors, and enteric peptides. Dig Dis Sci 1999; 44:63-74. [PMID: 9952225 DOI: 10.1023/a:1026697915937] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In the clinical setting, resection of the ileum results in an inferior functional outcome compared to jejunal resection. This may be related to a greater adaptive capacity of the ileum, intrinsic structural and functional differences, or regional differences in motor and hormonal function. Our aim was to evaluate the relative contributions of these factors to functional outcome after resection of the proximal or distal intestine. Twenty-four dogs underwent either intestinal transection or 50% resection of the proximal or distal intestine. Studies (nutritional status, absorption, adaptation, motility, peptide levels) were performed every four weeks until the animals were killed at 12 weeks. Caloric intake was similar in all four groups. Weight loss was greater and more sustained after distal resection (DR). Serum cholesterol levels decreased significantly only in the DR group. While stool weight and moisture were similar, the DR animals had persistent, significant steatorrhea. Intraluminal anaerobic bacteria and SCFA concentrations were significantly greater in the ileum but were not influenced by resection. Intestinal remnant length increased to a greater extent after proximal resection (PR), but circumference increased to a similar extent after both resections. Villus height and crypt depth increased significantly only after PR. MMC frequency was similar in all four groups. In the DR animals 26% of migrating motor complexes (MMCs) originated within the remnant. The jejunal remnant of these animals had a dominance of cluster activity similar to the intact distal ileum. Following PR, the postprandial motilin response was decreased. After DR, there were transient increases in neurotensin and PYY. Of the various factors evaluated, mucosal adaptation and the intestinal motor response appear most likely to explain the inferior nutritional and absorptive outcome associated with resection of the distal small intestine.
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Affiliation(s)
- J S Thompson
- Omaha VAMC, Department of Biomedical Sciences, Creighton University School of Medicine, Nebraska, USA
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