82 research outputs found
Endocrine disrupting chemicals (EDC) with (anti)estrogenic and (anti)androgenic modes of action affecting reproductive biology of Xenopus laevis: Effects on sexual steroids levels and biomarker expression in the liver
No full textAdult Xenopus laevis were exposed in vivo to ethinylestradiol, tamoxifen, methyldihydrotestosterone and flutamide as (anti)estrogenic and (anti)androgenic compounds, respectively, for four weeks at a concentration of 10(-8) M and to Lambro river water, a polluted river from Italy. Effects of the treatments were analysed by mRNA expression of retinol-binding protein (RBP), transferrin (TF), transthyretin (TTR) and vitellogenin (VTG) in the liver of male and female X. laevis, to analyse the potential of these genes to detect endocrine disrupting compounds (EDC) with different modes of action. In addition, plasma VTG and sex steroid levels, estradiol-17beta (E(2)) and testosterone (T), were analysed. Sex steroids were depressed by ethinylestradiol in both sexes whereas tamoxifen increased E(2) in females. The induction of VTG protein plasma levels was more pronounced at the protein level compared to hepatic VTG mRNA expression in response to estrogenic treatment but VTG mRNA expression detected both, estrogenic and antiestrogenic EDC. The mRNA expression of TF was decreased by estrogenic and increased by antiestrogenic treatment while TTR mRNA expression was down-regulated and RBP mRNA up-regulated by estrogenic exposure. The other treatments did not affect the mRNA expression of the examined genes
Exposure to Lambro river water disrupts spermatogenesis in Xenopus laevis
No full textAfrican clawed toad (Xenopus laevis) has been established as a very suitable model for studying the effects of Endocrine Disrupting Chemicals (EDCs) on reproductive biology. In a previous study we demonstrated severe alterations of testis organization (i.e. reduction of tubule diameter and number of germ cell nests and occurrence of small oocytes) in adult male X. laevis following a four weeks exposure to water from the river Lambro (LAM), a contaminated watercourse from Northern Italy. Data were compared with controls and exposed to ethinylestradiol (EE2), tamoxifen (TAM), methyl-dihydrotestosterone (MDHT) and flutamide (FLU), 10-8 M, as positive controls for (anti)estrogenic and (anti)androgenic activities. In this study, following the same experimental design, our attention was focused on the effects on the spermatogenic process. Germ cell nest profile was analysed in both paraffin and resin embedded testis within ten tubule sections for each specimen, numbered and classified into one of four different categories based on the following germ cell type: spermatogonia B (SPGB), primary spermatocytes (SPCI), secondary spermatocytes (SPCII), spermatids (SPD). The contingency test showed a general decrease of cell nests in LAM, EE2 and FLU exposed males and a general increase of cell nests in MDHT and TAM exposed males. Moreover, LAM exposed males, as well as EE2 and FLU exposed males, showed an increase in the number of SPGB nests and a decrease of SPD nests. A decrease of SPCII and an increase of SPCI nests was observed in 100% and in 44.4% EE2 exposed specimen sections, respectively. A decrease of SPCII and an increase of SPCI nests was observed in about 50% and 90% FLU exposed specimen sections, respectively. Even this last feature was less evident in LAM exposed males, data seem to confirm that Lambro river water is polluted by the concomitant presence of EDCs with mainly estrogenic and anti-androgenic modes of actions
Androgenic and antiandrogenic activity in water and sediment samples from the river Lambro, Italy.
No full textThe river Lambro is the most polluted tributary of the river Po in North Italy and was chosen as a representative water course discharging industrialized areas. Water and sediment samples of the river Lambro were investigated regarding the presence of endocrine disrupting compounds. A combined procedure was used consisting of solid-phase extraction and HPLC based fractionation of samples, of screening for (anti)androgenic activity using the yeast androgen screen (YAS) and of chemical analysis using HPLC–MS/MS and GC– MS. Androgenic and antiandrogenic activities were found in specific fractions of the water and sediment while the total extracts showed antiandrogenic activity only. The chemical analysis of the fractions and total extracts with antiandrogenic activities revealed the presence of compounds with suspected antiandrogenic potency such as bisphenol A, iprodione, nonylphenol, p,p0-DDE and tert-octylphenol but other unknown compounds contributed mainly to the observed antiandrogenic activities. The antiandrogenic load of the river Lambro ranged between 1.34 and 17.1 lM flutamide-equivalents and may pose a risk to aquatic environments. Future screenings for EDC in the environment that have the potential to interfere with reproduction of aquatic organisms should be extended to different modes of actions including (anti)androgenic ones
Endocrine disrupting chemicals (EDC) with (anti)estrogenic and (anti)androgenic modes of action affecting reproductive biology of Xenopus laevis: Effects on gonad morphology
No full textA number of man-made chemicals has been shown to mimic endogenous hormones and to induce alterations of reproductive physiology in wild populations. Of particular importance are compounds that mimic estrogens and androgens (and their antagonists), because of their central role in reproductive function. In this study, male and female adult South African clawed toads (Xenopus laevis) were exposed to ethinylestradiol (EE2), tamoxifen (TAM), methyldihydrotestosterone (MDHT) and flutamide (FLU) as (anti)estrogenic and (anti)androgenic model compounds, respectively, at a concentration of 10(-8) M, and to water from the river Lambro (LAM), a contaminated watercourse from Northern Italy. Potential disrupting effects on reproduction were studied by histological analyses of gonads. The strongest adverse effects were observed in EE2 and LAM exposed males, e.g. tubule mean diameter reduction, spermatogenic nest breakdown and interlobular wall thickening. In both groups, the occurrence of small oocytes within the seminiferous tubules was observed. In TAM and MDHT exposed females slight oocyte atresia and occurrence of spermatogenic nests were observed. In contrast to previous studies addressing the alteration of molecular biomarkers in the same experimental setup, histological analyses of gonads were very sensitive and indicated an adverse effect of water from Lambro River on reproductive physiology of X. laevis
Aromatase mRNA expression in the brain of adult Xenopus laevis exposed to Lambro river water and endocrine disrupting compounds.
No full textAromatase P450 (P450 arom; Cyp19) is a key enzyme for vertebrate reproduction and brain development that catalyzes the conversion of androgens to estrogens. The aim of this study was to improve the knowledge on EDC effects by analysing their potential impact on brain P450 arom in adult Xenopus laevis exposed for 4 weeks to an environmental sample, the water of the river Lambro (LAM), the most polluted tributary of the Po river in North Italy. Other groups were exposed to individual compounds 10_8 M tamoxifen (TAM), ethinylestradiol (EE2), flutamide (FLU) and methyldihydrotestosterone (MDHT) known for their (anti)estrogenic and (anti)androgenic modes of action. Expression of CYP19 was evaluated in brain extracts by quantitative RT-PCR, using a pair of primers located in the open reading frame (ORF) that allowed the simultaneous amplification of all transcripts (Aro-ORF) and a pair of primers specific for brain aromatase (Aro-B). Significant increase in Aro-ORF and Aro-B mRNA levels were observed in both females and males exposed to LAM. Different changes were observed for the model compounds using two pairs of primers. Aro-ORF mRNA expression was significantly increased in EE2 and MDHT exposed males and in FLU-exposed females, while it was significantly decreased in TAM exposed females. Aro-B mRNA was significantly increased in both sexes exposed to FLU and decreased in TAM exposed females. In conclusion, aromatase mRNA in the brain of X. laevis was regulated differentially in a gender specific manner by certain (anti)estrogenic and (anti)androgenic EDCs, supporting previous hypotheses that diverse compounds present in the river Lambro may induce feminization and demasculinization effects
Altered expression of aromatase mRNA in the brain of adult Xenopus laevis exposed to Lambro river water and (anti)estrogenic/(anti)androgenic model compounds
No full textThe production of estrogens in the brain is a highly important function in vertebrate reproduction and brain development. Aromatase (CYP19) that catalyzes the conversion of androgens to estrogens which is a rate-limiting step estrogen biosynthesis. Adult Xenopus laevis were exposed in vivo to Lambro (LAM) river water, the most polluted tributary of the Po river in North Italy, chosen as a representative water course discharging industrialized areas. In parallel, adult X. laevis were exposed to the following known (anti)estrogenic and (anti)androgenic compounds tamoxifen (TAM), ethinylestradiol (EE2), flutamide (FLU) and methyldihydrotestosterone (MDHT), 10−8 M. Expression of CYP19 was evaluated in brain obtained from females and males from all experimental conditions by quantitative RT_PCR using specific primers located in the ORF that allowed the simultaneous amplification of all transcripts. Differences in expression between treatments were analyzed by ANOVA followed by Bonferroni post-test. In general, males had similar CYP19 mRNA level compared to females, as usually observed in vertebrates. The mRNA expression of CYP19 was significantly up-regulated in both EE2 and MDHT exposed males and down-regulated in both MDHT and TAM exposed females. A general up-regulation of CYP19 mRNA expression was observed in females and males exposed to LAM. Moreover, in order to investigate the role of the tissue specific brain and gonad aromatase, recently described for X. laevis, primers were prepared, based on cDNA sequences for Xenopus cyp19 brain specific 5’UTR and gonad specific 5’UTR (Genbank accession numbers: AB272088, AB272087)
The Bioactivities of Lactic Acid-Fermented Arthrospira platensis and Its Application in Functional Beverages
No full textThe demand for functional beverages with clean labels is growing. Arthrospira platensis and fermented products offer bioactive compounds, including antimicrobials. This study aimed to produce food-grade extracts from lactic acid-fermented A. platensis and evaluate its antimicrobial activity, lipid-reducing and glucose uptake effects, and antioxidant properties. An in situ test was also conducted to assess antimicrobial activity in commercial soft drinks against Escherichia coli. Arthrospira platensis was fermented with five different QPS LAB strains: Limosilactobacillus fermentum UPCCO 1986, Companilactobacillus farciminis UPCCO 4841, Levilactobacillus brevis UPCCO 4873, Lentilactobacillus diolivorans UPCCO 5571, and Latilactobacillus curvatus UPCCO 6133, obtaining good results in aerobic and anaerobic conditions. The results have shown that the most versatile strain in fermenting biomass is L. brevis UPCCO 4873. Important in vitro antimicrobial activity was seen against Salmonella enterica, Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. The extracts that exerted the highest antimicrobial activity (4841AE/AN, 5571AE, and 6133AN) were assessed for the in situ antimicrobial activity against E. coli ATCC 11229. Overall, the antimicrobial activity of the extracts was concentration-dependent, with higher concentrations exhibiting bactericidal effects and lower concentrations displaying bacteriostatic effects. Extracts from fermented A. platensis have also significantly reduced the neutral lipid reservoirs, which were not observed without fermentations. The strongest lipid-reducing effect was obtained with A. platensis fermented with Levilactobacillus brevis UPCCO 4873. This work opens the possibility of developing bioactive extracts or natural preservatives from fermented microalgae to be used in novel functional beverages
Hierridin B Isolated from a Marine Cyanobacterium Alters VDAC1, Mitochondrial Activity, and Cell Cycle Genes on HT-29 Colon Adenocarcinoma Cells
No full textBackground: Hierridin B was isolated from a marine cyanobacterium Cyanobium sp. strain and induced cytotoxicity selectively in HT-29 adenocarcinoma cells. The underlying molecular mechanism was not yet elucidated. Methods: HT-29 cells were exposed to the IC50concentration of hierridin B (100.2 μM) for 48 h. Non-targeted proteomics was performed using 2D gel electrophoresis and MALDI-TOF/TOF mass spectrometry. The mRNA expression of apoptotic and cell cycle genes were analyzed by real-time PCR. Automated quantification of 160 cytoplasm and mitochondrial parameter was done by fluorescence microscopy using CellProfiler software. Results: Proteomics identified 21 significant different proteins, which belonged to protein folding/synthesis and cell structure amongst others. Increase of VDAC1 protein responsible for formation of mitochondrial channels was confirmed by mRNA expression. A 10-fold decrease of cytoskeleton proteins (STMN1, TBCA) provided a link to alterations of the cell cycle. CCNB1 and CCNE mRNA were decreased two-fold, and P21CIP increased 10-fold, indicative of cell cycle arrest. Morphological analysis of mitochondrial parameter confirmed a reduced mitochondrial activity. Conclusion: Hierridin B is a potential anticancer compound that targets mitochondrial activity and function.This research was partially supported by FCT—Foundation for Science and Technology under the project UID/Multi/04423/2013 and by the Structured Program of R & D & I INNOVMAR—Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR), funded by the Northern Regional Operational Program (NORTE2020) through the European Regional Development Fund (ERDF). Ralph Urbatzka was supported by the FCT scholarship SFRH/BPD/112287/2015, and Pedro N. Leão by FCT grant IF/01358/2014
Identification of endocrine disrupting chemicals from a polluted river (Lambro) in Italy using bioassays and chemical analysis.
No full textRecently increasing concern evolved about endocrine disrupting chemicals (EDC) in the environment. Some studies showed that these chemicals can influence the reproductive system of animals in the wildlife producing e.g. intersex phenomenon in fishes or in marine snails. In this joint project a polluted river (Lambro) was investigated as a source of EDC to the wildlife of the major Italian watercourse, the river Po. Water and sediment samples from the Lambro river were fractionated and forwarded to bioassays (MVLN cells and yeast screening assay (YES)) in order to identify (anti)estrogenic activities of fractions. All fractions have been chemically analysed qualitatively as well as quantitatively for known EDC and, in addition, an immunoassay for estradiol (E2) was used to quantify E2 amounts. A proteomics analysis of the MVLN cells was conducted from treated cells relative to the control. This combined assay using chemical and biological analyses revealed some chemicals to act estrogenic. Good coincidence was found between the assays and some fractions from the water and the sediment samples were identified as being estrogenic. The chemical analysis showed that E2, E1, E3, Bisphenol A, and teroctylphenol are the most abundant compounds in the fractions with the highest estrogenic activities. The protein pattern of MVLN cells was changed in all treated samples relative to control. We conclude that these chemicals found in the Lambro water are present in concentrations affecting the cell based assays, change the protein patterns in the MVLN cells and may therefore act as EDC in the wildlife. Further investigations will show how fishes and amphibians are affected by the Lambro water conducting morphological studies and the expression of molecular biomarkers
Obesity: The metabolic disease, advances on drug discovery and natural product research
No full textObesity is a global health threat. OECD reported that more than half (52%) of the adult population in the European Union is overweight or obese. Obesity and obesity-related co-morbidities have deep negative effects on morbidity, mortality, professional and personal quality of life. Healthcare costs represent a negative impact of this disease, with an associated economic cost of 100 billion US$ per year in the United States. The most prescribed drugs for obesity treatment worldwide are orlistat, and phentermine/topiramate extended release, while the major prescribed drug for the same disease in the US are exenatide and dapagliflozin. The so far developed drugs, targeting weight loss, have a long history of malignant secondary effects. There is still a lack of efficient and safe drugs to treat obesity and related metabolic complications since in many cases cure cannot be reached by bariatric surgery or healthy lifestyle habits. Terrestrial and aquatic organisms are a promising source of valuable, bioactive compounds, often with interest for human health. Some of the natural compounds or organisms have been used for centuries by humans as traditional medicine foods. In this review, we give insights into the adipose tissue function and development, and the progress in traditional anti-obesity pharmacotherapy. A major focus is to highlight the state of the art of natural compounds with anti-obesity properties and their potential as candidates for drug development; an overview is given about natural compounds derived from different marine animal sources, cyanobacteria, marine phytoplankton, fungus or plants. © 2016 Bentham Science Publishers.This study was funded by the Project MARBIOTECH (reference NORTE-07-0124-FEDER-000047) within the SR&TD Integrated Program MARVALOR - Building research and innovation capacity for improved management and valorization of marine resources, supported by ON.2 Program and by the European Regional Development Fund (ERDF) through COMPETE - Operational Competitiveness Programme and NOVOMAR (reference 0687-NOVOMAR- 1-P), and national funds through FCT - Foundation for Science and Technology, through the project UID/Multi/04423/2013. Ralph Urbatzka was supported by grant SFRH/BPD/112287/2015 (FCT)
- …
