25 research outputs found
Impact du secrĂ©tome adipocytaire sur lâhormonothĂ©rapie dans le cancer du sein en situation de surpoids/obĂ©sitĂ©
National audienceLâobĂ©sitĂ©, facteur de risque Ă©tabli de cancer du sein chez les femmes mĂ©nopausĂ©es, est aussi responsable de plus forts taux de rĂ©cidives et de mortalitĂ©. Dans ce contexte, nos travaux Ă©valuent lâimpact du secrĂ©tome adipocytaire (SA) dans la moindre rĂ©ponse Ă lâhormonothĂ©rapie. Pour cela, 1/ des cellules cancĂ©reuses mammaires ont Ă©tĂ© soit co-cultivĂ©es avec des cellules souches adipeuses (CSAd) humaines (hMAD) diffĂ©renciĂ©es en adipocytes matures (AM) soit cultivĂ©es en prĂ©sence de milieux conditionnĂ©s (MC), puis traitĂ©es avec un anti-estrogĂšne (anti-E ; TamoxifĂšne Tx ou Fulvestrant Fv). La prolifĂ©ration cellulaire a Ă©tĂ© mesurĂ©e par fluorescence Ă la rĂ©sazurine (Fluoroskan Ascent FLÂź, n=3) et suivie en temps rĂ©el par impĂ©dancemĂ©trie (iCELLigence, n=3). 2/ Lâimpact du surpoids a Ă©tĂ© Ă©valuĂ© en utilisant des AM diffĂ©renciĂ©s Ă partir de CSAd de femmes minces ou obĂšses cultivĂ©es en prĂ©sence de cellules MCF-7 et de Fv. Dans nos diffĂ©rents modĂšles, les SA sont capables de majorer la prolifĂ©ration des cellules MCF-7, rĂ©cepteur aux estrogĂšnes positives (RE+), et dâinhiber totalement lâeffet antiprolifĂ©ratif du Tx et du Fv. Lâutilisation de cellules MDA-MB-231 RE- a montrĂ© que le SA majore la prolifĂ©ration cellulaire et contrecarre lâeffet antiprolifĂ©ratif du Tx, suggĂ©rant que les effets observĂ©s ne passeraient pas exclusivement par la voie du RE dans notre modĂšle. Par ailleurs, en utilisant des AM de femmes de poids variables, seuls les SA correspondant aux femmes dâIMC>30 amoindrissent lâefficacitĂ© du Fv, cet effet sâaccompagnant dâune augmentation de lâexpression du gĂšne OB-R. Ainsi, nos rĂ©sultats prĂ©liminaires suggĂšrent que le SA limiterait lâefficacitĂ© de lâhormonothĂ©rapie et ce, de façon plus prononcĂ©e en cas de surpoids, ce qui pourrait contribuer au processus dâĂ©chappement tumora
LâactivitĂ© physique spontanĂ©e en condition dâobĂ©sitĂ© ralentit la croissance tumorale en modulant les signaux hormonaux tissulaires
Nutrition en pathologie : cancer, insuffisance dâorganes, rĂ©animation, pathologies digestivesâŠCOMMUNICATIONS AFFICHEESIntroduction et but de lâĂ©tude: En situation dâobĂ©sitĂ©, les dĂ©rĂ©gulations du tissu adipeux induisent la sĂ©crĂ©tion dâĆstradiol et de leptine (pro-inflammatoire) aux dĂ©pens d'adiponectine (anti-inflammatoire), une augmentation du stress oxydant associĂ©e Ă une baisse des capacitĂ©s anti-oxydantes favorisant un microenvironnement pro-carcinogĂšne. LâactivitĂ© physique (AP), facteur de prĂ©vention de lâobĂ©sitĂ© et des cancers, favorise une inflammation aigĂŒe modĂ©rĂ©e, la rĂ©ponse anti-oxydante et la sĂ©crĂ©tion dâadipokines anti-inflammatoires. Les mĂ©canismes de protection de lâAP dans le cancer mammaire sont mal connus. Le but est de caractĂ©riser le dialogue inter-organe induit par lâAP spontanĂ©e et lâimpact sur la croissance tumorale dans un modĂšle de carcinogenĂšse mammaire murin en situation dâobĂ©sitĂ©.MatĂ©riel et mĂ©thodes: Des souris C57BL/6 ĂągĂ©es (n=10/groupe), ovariectomisĂ©es, nourries avec un rĂ©gime hyper-lipidique, sont hĂ©bergĂ©es en environnement standard (ES) ou en environnement enrichi (EE) favorisant lâAP spontanĂ©e. AprĂšs 4 semaines, des cellules tumorales syngĂ©niques EO771 sont implantĂ©es par fat-pad. Au sacrifice, lâexploration des adipokines et des cytokines a Ă©tĂ© conduite dans les organes dâintĂ©rĂȘt (tumeur, tissu adipeux inguinal, gastrocnĂ©mien, plasma) ainsi que la caractĂ©risation du statut oxydatif et des voies de signalisation (JNK, AKT, NFÎșB, p38, S6K1) de la tumeur.RĂ©sultats et Analyse statistique : LâEE entraĂźne une augmentation de lâAP sans modification des masses maigres et adipeuses, ni des mĂ©tabolites Ă©nergĂ©tiques (triglycĂ©rides, glucose). Lâanalyse factorielle multiple montre que les variables expliquant les diffĂ©rences entre individus sont les masses adipeuses (totale, viscĂ©rale et inguinale), lâadiponectine plasmatique, les taux de leptine des tissus dâintĂ©rĂȘt, les capacitĂ©s anti-oxydantes et les voies de signalisation intra-tumorales. Les adipokines plasmatiques sont corrĂ©lĂ©es aux masses adipeuses et aux voies de signalisation tumorales. Le taux de leptine dans le gastrocnĂ©mien est corrĂ©lĂ© avec celui de la tumeur (rÂČ=0,57 p<0,05) et montre une forte diminution chez les animaux EE vs ES (tumeur : 0,30 ± 0,07 vs 0,60 ± 0,10 pg/mg ; p<0,05 ; gastrocnĂ©mien : 0,09 ± 0,03 vs 0,45 ± 0,11 pg/mg ; p<0,05). LâIL6 plasmatique est diminuĂ©e et associĂ©e Ă une rĂ©duction du stress oxydant tumoral (thiols protĂ©iques, GST, thiorĂ©doxine) pour les souris EE vs ES. Une baisse de lâactivation des voies tumorales de signalisation est observĂ©e pour les souris EE vs ES, corrĂ©lĂ©e positivement avec les masses musculaires et nĂ©gativement avec les masses adipeuses.Conclusion: Ces rĂ©sultats montrent que l'activitĂ© physique spontanĂ©e en condition dâobĂ©sitĂ© ralentie la croissance tumorale, en modifiant le dialogue inter-organe, conduisant Ă une rĂ©duction de lâinflammation et du stress oxydatif du microenvironnement tumoral. Une consommation de la leptine est observĂ©e dans la tumeur et le gastrocnĂ©mien alors que la production au niveau du tissu adipeux et la distribution plasmatique ne semblent pas affectĂ©es. Ainsi, lâactivitĂ© physique module les signaux hormonaux tissulaires conduisant Ă une moindre stimulation des voies de signalisation nĂ©cessaires Ă la croissance tumorale
L-Arginine supplementation prevents allodynia and hyperalgesia in painful diabetic neuropathic rats by normalizing plasma nitric oxide concentration and increasing plasma agmatine concentration
Neuropathic pain is a common diabetic complication. It is characterized by symptoms of spontaneous and stimulus-evoked pain including hyperalgesia and allodynia. L-Arginine is a common precursor of many metabolites of biological interest, in particular, nitric oxide (NO), ornithine, and hence polyamines. In central nervous system, NO, glutamate, and polyamines share an N-methyl-D-aspartate (NMDA) receptor-mediated effect. We hypothesized that a variation in arginine metabolism caused by diabetes may contribute to development and maintenance of neuropathic pain and to the worsening of clinical and biological signs of diabetes.We examined whether oral L-arginine supplementation (2.58 ± 0.13 g/l in drinking water for 3 weeks) could improve the development of neuropathic pain and the clinical, biological, and metabolic complications of diabetes in streptozocin (STZ)-induced diabetic (D) rats.STZ administration induced classical symptoms of type 1 diabetes. Diabetic rats also displayed mechanical hypersensitivity, tactile, and thermal allodynia. Plasma citrulline and NO levels were increased in diabetic hyperalgesic/allodynic rats. L-Arginine supplementation failed to reduce hyperglycaemia, polyphagia, and weight loss. Moreover, it abolished hyperalgesia and allodynia by normalizing NO plasma concentration and increasing plasma agmatine concentration.L-Arginine supplementation prevented the development of mechanical hyperalgesia, tactile, and thermal allodynia in painful diabetic neuropathy with concomitant reduction of NO and increased agmatine production, offering new therapeutic opportunities for the management of diabetic neuropathic pain
Activité physique pendant les traitements adjuvants du cancer du sein
National audienceLâobjectif principal de cette Ă©tude Ă©tait dâĂ©valuer lâeffet dâune intervention dâactivitĂ© physique (AP) concomitante aux traitements adjuvants du cancer du sein sur lâĂ©volution des hormones et cytokines circulantes. Lâobjectif secondaire Ă©tait dâĂ©valuer les relations entre niveaux dâAP et taux circulants dâhormones et de cytokines. Des femmes dĂ©butant une chimiothĂ©rapie adjuvante pour un cancer du sein localisĂ© ont participĂ© Ă un essai randomisĂ© Ă©valuant la faisabilitĂ© dâune intervention de 6 mois dâAP versus la prise en charge diĂ©tĂ©tique habituelle. Les taux circulants des marqueurs biologiques (insuline, insulin-like growth factor 1 [IGF1], estradiol, adiponectine, leptine, interleukine 6 [IL6] et facteur de nĂ©crose tumorale α [TNFα]) Ă©taient mesurĂ©s en dĂ©but dâintervention et Ă 6 mois. Le niveau dâAP Ă©tait Ă©valuĂ© Ă lâaide de lâInternational Physical Activity Questionnaire (IPAQ). Lâintervention dâAP nâa pas induit dâamĂ©lioration significative des taux dâhormones et de cytokines comparĂ©e au bras tĂ©moin. Dans une analyse de lâensemble de la cohorte (n=58), le taux dâIGF1 Ă©tait significativement associĂ© Ă lâĂ©volution du niveau dâAP des patientes (p=0,03). AprĂšs 6 mois, le taux d'IGF1 a diminuĂ© de 11,2% chez les femmes ayant maintenu ou atteint un niveau Ă©levĂ© dâAP (â„3000 MET-minutes/semaine), tandis qu'il a augmentĂ© de 12,4% chez les femmes prĂ©sentant un niveau modĂ©rĂ© ou faible dâAP Ă 6 mois. Ces rĂ©sultats suggĂšrent un effet bĂ©nĂ©fique dâun niveau Ă©levĂ© dâAP (Ă©quivalent Ă 2h20 de marche active par jour) sur le taux circulant dâIGF1, prĂ©cĂ©demment reliĂ© au pronostic du cancer du sein. Dâautres Ă©tudes Ă plus grande Ă©chelle Ă©valuant diffĂ©rentes modalitĂ©s dâintervention sont essentielles pour amĂ©liorer les connaissances sur lâintĂ©rĂȘt potentiel de lâactivitĂ© physique pendant et aprĂšs les traitements adjuvants du cance
Bis(4-hydroxy-2H-chromen-2-one) Coumarin Induces Apoptosis in MCF-7 Human Breast Cancer Cells Through Aromatase Inhibition
AIM: The present investigation aimed to examine the therapeutic potential of the new coumarin derivative bis(4-hydroxy-2H-chromen-2-one) coumarin (4HC) against breast cancer. MATERIALS AND METHODS: For this purpose, the effects of 4HC treatment on the proliferation of MCF-7 breast cancer cells and on MCF-10a non-cancerous cells were evaluated using a fluorescent assay. Cell cycle distribution and apoptosis were measured by image cytometry. The expression level of aromatase (CYP19A1) and apoptosis-related genes were determined by real-time PCR. RESULTS: MCF-7 mammary cancer cell proliferation was significantly decreased within 24 h after treatment with 4HC at 50 muM, while no effect was observed on the viability of MCF-10a non-cancerous mammary cells. 4HC also increased the percentage of the cells in the G2/M phase, inducing apoptosis. Real-time PCR revealed that 4HC induced MCF-7 mortality through an up-regulation of Bax and a down-regulation of Bcl-2, resulting in an increase in caspase-3 gene expression. The increased expression of apoptosis-related genes was accompanied by a decrease in CYP19A1 gene expression. CONCLUSION: 4HC selectively inhibits proliferation of MCF-7cells in vitro. Moreover, 4HC has inhibitory effects on aromatase gene expression and promoting effects on apoptosis, in MCF-7 cells
Cell Cycle Synchronization of the Murine EO771 Cell Line Using Double Thymidine Block Treatment
International audienceThis study shows that double thymidine block treatment efficiently arrests the EO771 cells in the S-phase without altering cell growth or survival. A long-term analysis of cell behavior, using 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) staining, show synchronization to be stable and consistent over time. The EO771 cell line is a medullary breast-adenocarcinoma cell line isolated from a spontaneous murine mammary tumor, and can be used to generate murine tumor implantation models. Different biological (serum or amino acid deprivation), physical (elutriation, mitotic shake-off), or chemical (colchicine, nocodazole, thymidine) treatments are widely used for cell synchronization. Of the different methods tested, the double thymidine block is the most efficient for synchronization of murine EO771 cells if a large quantity of highly synchronized cells is recommended to study functional and biochemical events occurring in specific points of cell cycle progression
Immunonutrition improves functional capacities in head and neck and esophageal cancer patients undergoing radiochemotherapy: A randomized clinical trial
Background & aims: Malnutrition is frequent in head and neck (HN) and esophageal cancer patients and aggravated by radiochemotherapy (RCT), increasing morbi-mortality and treatment toxicity. Our goal was to investigate the effect of immunonutrition consisting of an arginine, omega-3 fatty acid, nucleotides-enriched diet on nutritional status, and functional capacity in HN or esophageal cancer patients undergoing RCT. Methods: 37 patients were randomized in a double-blind clinical trial. 5 days before and until the end of RCT (5-7 weeks), they received either an Immunomodulating Enteral Nutrition (IEN) or an isonitrogenous, isoenergetic Standard Enteral Nutrition (SEN). Anthropometrical parameters, nutritional risk index (NRI), serum albumin, plasma antioxidant capacity, and functional capacity were recorded between the beginning and the end of RCT. Results: A significant gain in total body weight (+2.1 +/- 3.1 kg) was observed in IEN patients. Albuminemia and NRI were improved concomitantly in IEN malnourished patients. Plasma antioxidant capacity was improved (+100 +/- 13 mu M EqTrolox) in IEN patients. Functional capacity measured by WHO Performance Status and Karnofsky index was maintained in IEN patients but significantly reduced in SEN patients. Conclusions: These preliminary data show that immunonutrition could improve the nutritional status together with functional capacity in HN and esophageal cancer patients undergoing RCT. (C) 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved
Increased consumption of salmon during pregnancy partly prevents the decline of some plasma essential amino acid concentrations in pregnant women
International audienceBackground & aims: Oily fish is a good source of n-3 long-chain polyunsaturated fatty acids. Since these fatty acids may change efficiency of amino acid (AA) absorption, we determined whether increased salmon consumption influences plasma AA concentrations in pregnant women and their newborns. Methods: Pregnant women were randomly allocated to remain on their habitual diet (n = 61; control group) or to consume two 150 g farmed salmon portions per week from 20 weeks pregnancy until birth (n = 62; salmon group). Plasma AA concentrations were determined in women at w20, w34 and w38 of pregnancy and in umbilical cord at delivery. Results: Concentrations of arginine, valine, leucine and lysine were affected by both time of pregnancy and salmon intake (p 0.05). Conclusions: Two portions/wk of oily fish increased plasma essential AA concentrations during pregnancy and could contribute to a maternal health benefit. Two portions/wk of salmon did not affect plasma AA concentrations in the newborn. (C) 2013 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved