ABSTRACT
Abstract In Argentina there are no reports on Aspergillus fumigatus fumagillin-producingstrains. In this study we describe the isolation and mycotoxin production capacity of ten A.fumigatus strains isolated from farm and clinical samples. Farm strains were isolated frommilk samples taken from dairy cows in Córdoba province, some of which were associated withsubclinical mastitis. A culture medium was defined to optimize fumagillin production and adetection method was developed by HPLC chromatography. It is known that in addition to thehost immune status, strain virulence is a fundamental characteristic that will determine itspathogenicity and, in this sense, fumagillin is considered to be among the virulence factors. Inthe present work, all the strains tested for the production of fumagillin were able to synthesizeit, highlighting that the strain A. fumigatus RC2243, from a milk sample from a cow with clinicalmastitis, was the most productive. The existence of fumagillin-producing strains represents apotential risk of mycotoxins being transferred to raw milk, constituting a public health risk.
Resumen En Argentina no existen reportes sobre cepas de Aspergillus fumigatus productoras de fumagilina. En este trabajo se describe el aislamiento y la producción de dicha micotoxina clínicaspor 10 cepas, provenientes del medioambiente rural y aisladas de muestras clínicas. Las cepasde origen rural fueron aisladas de vacas lecheras en tambos de la provincia de Córdoba, yalgunas de esas cepas se asociaron a casos de mastitis subclínica. Se definió la composición deun medio de cultivo para optimizar la producción de fumagilina y se desarrolló un método decromatografía HPLC para su determinación. Es conocido que, además del estado inmunitario delhuésped, la virulencia de la cepa es una de las características fundamentales que determinansu potencial patogénico y, en este sentido, la fumagilina es considerada un factor de virulencia. En el presente trabajo todas las cepas estudiadas fueron capaces de sintetizarla y la cepa A.fumigatus RC2243, proveniente de leche de una vaca con mastitis subclínica, se destacó comola cepa más productora. La existencia de cepas productoras de fumagillina representa un riesgopotencial por el pasaje de dicha micotoxina a la leche, lo cual constituye un problema para lasalud pública.
ABSTRACT
Objective: To study the secondary metabolites of marine-derived Aspergillus fumigatus MDCW-15. Methods: The secondary metabolites were isolated and purified by column chromatography over silica gel. And their structures were identified by the spectroscopic analysis of NMR and MS. The antifungal bioactivities were assayed by paper diffusion. Results: A new fumagillin compound 1 and a known compound 2 were isolated from the fermentation broth of marine-derived Aspergillus fumigatus MDCW-15. The antifungal bioactivities were assayed by paper diffusion. Compounds 1 and 2 showed antifungal activity against Candida albicans with an equal MIC value of 32.0 μg/mL. Conclusion: Compound 1 is a new compound named 2'-cis- fumagiringillin. Compounds 1 and 2 exhibit antifungal activities.
ABSTRACT
Type 2 diabetes (T2DM) is a progressive insulin secretory defect accompanied by resistance to insulin, and thereby making glycemic control a major concern in the treatment of these patients. Oral drug administration, though a popular option for its non-invasiveness, suffer from poor bioavailability. It could be related to the efflux transport of intestinal P-glycoprotein (Pgp). In the present study, we explored the binding interactions of antidiabetic drugs i.e., sulfonylurea drugs (glimepiride, glipizide, glyburide) and rapid acting insulin secretagogues viz., nateglinide, repaglinide and rosiglitazone; and Pgp inhibitors i.e., Generation I (verapamil and tamoxifen), III (tetradrine and tariquidar), and natural inhibitors (fumagillin and piperine) in mouse Pgp model. Our results revealed that fumagillin piperine and verapamil possess maximum interaction energies with Pgp compared to antidiabetic drugs. These observations elucidate the role of fumagillin and piperine as potential natural compounds which could intervene in the efflux action of Pgp in extruding the antidiabetic drugs and may have implications for increasing efficacy of oral antidiabetic therapy.
ABSTRACT
Background and purpose: Fumagillin is an inhibitor of type 2 methionine aminopeptidase that can block blood vessel formation. However, its molecular mechanism and therapeutic value in colon cancer still remain to be elucidated.ln this study, the effect of Fumagillin on the growth of colon cancer was examined. Methods: Twenty mice were divided into 4 groups and injected subcutaneously with 5×10~5/L WiDr or HT-29 cells in 200 μL phosphate-buffered saline (PBS) respectively. After 4 weeks, intraperitoneal injections of Fumagillin (0.1 mg/kg), Cyclo (1 mg/kg), or both were given every 2 days for 4 weeks. The tumor weight and microvessel density (MVD) were examined. Gene-expression profiles were examined by microarray analysis of human umbilical endothelial cells (HUVECs). Results: The Fumagillin-treated mice showed smaller tumor mass and lower MVD-CD105 levels than control ones. In vitro proliferation and tube formation of HUVEC was also significantly decreased by Fumagillin. Microarray analysis of Fumagillin-treated HUVECs showed up-regulation of 71 genes and down-regulation of 143 genes. Expression changes were involved in cell proliferation, migration, adhesion and gene transcription. Quantitative real time-polymerase chain reaction and Westem blot revealed decreased expression of cyclin E2, activated leukocyte cell adhesion molecule (ALCAM), and intercellular adhesion molecule-1 (ICAM-1) genes in the presence of Fumagillin. Conclusion: Fumagillin was found to suppress colorectal cancer growth by suppressing angiogenesis. The down-regulation of cyclin E2, ALCAM and ICAM-1 by fumagillin may be involved in the anti-angiogenesis.
ABSTRACT
The antiangiogenic effects of novel agent KJ3, Betulinic acid, and Fumagillin on the neovascularization were studied by examining ultrastructural alterations in the vasculature of synthetic gelform and mouse neuroblastoma C1300. Small pieces of gelform with 0.4 % agar were introduced subcutaneously (s.c.) in 7 week old male CH3/HeJ mice. After the LD50s were determined by FACS analysis, a third of LD50 of three drugs were injected either locally or intraperitoneally every other day for 14 days. A/J mice were inoculated s.c. with the C1300 neuroblastoma cell line, then either saline or three drugs were injected in the same manner. The antiangiogenic effects of three drugs were studied by measuring the histologic changes in tumors, and immunostaining for CD34, VIII/vWF, CD105, and thymidine phosphorylase. In the drug treated groups, the number of vessels in gelform experiments and C1300 neuroblastoma experiments were lower than the corresponding values in the control. The histologic findings were significantly different in drug treated groups on day 7, but these were not significant on day 14. These results imply that antiangiogenic agents were effective when the tumor burden is minimal.
Subject(s)
Animals , Humans , Male , Mice , Agar , Angiogenesis Inhibitors , Cell Line , Lethal Dose 50 , Neuroblastoma , Thymidine Phosphorylase , Tumor BurdenABSTRACT
Background and purpose:Fumagillin is an inhibitor of type 2 methionine aminopeptidase that can block blood vessel formation. However, its molecular mechanism and therapeutic value in colon cancer still remain to be elucidated.In this study, the effect of Fumagillin on the growth of colon cancer was examined. Methods:Twenty mice were divided into 4 groups and injected subcutaneously with 5?105/L WiDr or HT-29 cells in 200 ?L phosphate-buffered saline (PBS) respectively. After 4 weeks, intraperitoneal injections of Fumagillin (0.1 mg/kg), Cyclo (1 mg/kg), or both were given every 2 days for 4 weeks. The tumor weight and microvessel density (MVD) were examined. Geneexpression profiles were examined by microarray analysis of human umbilical endothelial cells (HUVECs). Results: The Fumagillin-treated mice showed smaller tumor mass and lower MVD-CD105 levels than control ones. In vitro proliferation and tube formation of HUVEC was also significantly decreased by Fumagillin. Microarray analysis of Fumagillin-treated HUVECs showed up-regulation of 71 genes and down-regulation of 143 genes. Expression changes were involved in cell proliferation, migration, adhesion and gene transcription. Quantitative real time-polymerase chain reaction and Western blot revealed decreased expression of cyclin E2, activated leukocyte cell adhesion molecule (ALCAM), and intercellular adhesion molecule-1 (ICAM-1) genes in the presence of Fumagillin. Conclusion: Fumagillin was found to suppress colorectal cancer growth by suppressing angiogenesis. The down-regulation of cyclin E2, ALCAM and ICAM-1 by fumagillin may be involved in the anti-angiogenesis.