GLUT1 activity contributes to the impairment of PEDF secretion by the RPE

Purpose: In this study, we aimed to understand whether glucose transporter 1 (GLUT1) activity affects the secretion capacity of antiangiogenic factor pigment epithelium-derived factor (PEDF) by the RPE cells, thus explaining the reduction in PEDF levels observed in patients with diabetic retinopathy (DR).Methods: Analysis of GLUT1 expression, localization, and function was performed in vitro in RPE cells (D407) cultured with different glucose concentrations, corresponding to non-diabetic (5 mM of glucose) and diabetic (25 mM of glucose) conditions, further subjected to normoxia or hypoxia. The expression of PEDF was also evaluated in the secretome of the cells cultured in these conditions. Analysis of GLUT1 and PEDF expression was also performed in vivo in the RPE of Ins2(Akita) diabetic mice and age-matched wild-type (WT) controls.Results: We observed an increase in GLUT1 under hypoxia in a glucose-dependent manner, which we found to be directly associated with the translocation and stabilization of GLUT1 in the cell membrane. This stabilization led to an increase in glucose uptake by RPE cells. This increase was followed by a decrease in PEDF expression in RPE cells cultured in conditions that simulated DR. Compared with non-diabetic WT mice, the RPE of Ins2Akita mice showed increased GLUT1 overexpression with a concomitant decrease in PEDF expression.Conclusions: Collectively, our data show that expression of GLUT1 is stimulated by hyperglycemia and low oxygen supply, and this overexpression was associated with increased activity of GLUT1 in the cell membrane that contributes to the impairment of the RPE secretory function of PEDF

The anti-inflammatory and antitumor effects of medicinal plants: Arctium lappa, Solanum torvum and Lobelia inflata

Introduction: Medicinal plants have been used since antiquity to treat illnesses and injuries. Considering their global use, many natural products have been investigated with the aim to get new drugs. Methods: The search was based on relevant articles indexed in PubMed, Scielo and Scopus. The search terms used were: medicinal plants, Arctium lappa, Solanum torvum, Lobelia inflata, anti-inflammatory effects, antimicrobial activity and antitumor effects. Development: Arctium lappa leads to the inhibition of nitric oxide synthase (iNOS) expression and nitric oxide (NO) production and inhibits the growth of some tumor cell lines. Solanum torvum can promote inhibition of inflammatory mediators release, and reduces the melanoma formation. Lobelia inflata can reduce the number of white blood cells, the TNF-α and IL-6 levels and the melanoma growth. Conclusion: The active principles present in these medicinal plants, including flavonoids and other phenolic compounds with antioxidant activity, can scavenge free radicals and therefore be effective against tumors, such as melanoma and skin cancer

Yeast as a model organism for studying the evolution of non-standard genetic codes

During the last 30 years, a number of alterations to the standard genetic code have been uncovered both in prokaryotes and eukaryotic nuclear and mitochondrial genomes. But, the study of the evolutionary pathways and molecular mechanisms of codon identity redefinition has been largely ignored due to the assumption that non-standard genetic codes can only evolve through neutral evolutionary mechanisms and that they have no functional significance. The recent discovery of a genetic code change in the genus Candida that evolved through an ambiguous messenger RNA decoding mechanism is bringing that naive assumption to an abrupt end by showing, in a rather dramatic way, that genetic code changes have profound physiological and evolutionary consequences for the species that redefine codon identity. In this paper, the recent data on the evolution of the Candida genetic code are reviewed and an experimental framework based on forced evolution, molecular genetics and comparative and functional genomics methodologies is put forward for the study of non-standard genetic codes and genetic code ambiguity in general. Additionally, the importance of using Saccharomyces cerevisiae as a model organism for elucidating the evolutionary pathway of the Candida and other genetic code changes is emphasised.publishe

Altered bone microarchitecture in a type 1 diabetes mouse model Ins2 Akita

Type 1 diabetes mellitus (T1DM) has been associated to several cartilage and bone alterations including growth retardation, increased fracture risk, and bone loss. To determine the effect of long term diabetes on bone we used adult and aging Ins2(Akita) mice that developed T1DM around 3-4 weeks after birth. Both Ins2(Akita) and wild-type (WT) mice were analyzed at 4, 6, and 12 months to assess bone parameters such as femur length, growth plate thickness and number of mature and preapoptotic chondrocytes. In addition, bone microarchitecture of the cortical and trabecular regions was measured by microcomputed tomography and gene expression of Adamst-5, Col2, Igf1, Runx2, Acp5, and Oc was quantified by quantitative real-time polymerase chain reaction. Ins2(Akita) mice showed a decreased longitudinal growth of the femur that was related to decreased growth plate thickness, lower number of chondrocytes and to a higher number of preapoptotic cells. These changes were associated with higher expression of Adamst-5, suggesting higher cartilage degradation, and with low expression levels of Igf1 and Col2 that reflect the decreased growth ability of diabetic mice. Ins2(Akita) bone morphology was characterized by low cortical bone area (Ct.Ar) but higher trabecular bone volume (BV/TV) and expression analysis showed a downregulation of bone markers Acp5, Oc, and Runx2. Serum levels of insulin and leptin were found to be reduced at all-time points Ins2(Akita). We suggest that Ins2(Akita) mice bone phenotype is caused by lower bone formation and even lower bone resorption due to insulin deficiency and to a possible relation with low leptin signaling.F. R. Carvalho and S. M. Calado acknowledge the financial support from the Portuguese Foundation for Science and Technology (FCT) through Ph.D. fellowships SFRH/BD/76429/2011 and SFRH/BD/76873/2011, respectively. This study was funded in part by CCMAR funding from European Regional Development Fund (ERDF) under COMPETE Program and through FCT under PEst-C/MAR/LA0015/2011 project and through UID/Multi/04326/2013 project. GA Silva was funded by (PIRG05-GA-2009-249314-EyeSee) and Research Center Grant UID/BIM/04773/2013 to CBMR

Altered bone microarchitecture in a type 1 diabetes mouse model Ins2 (Akita)

Type 1 diabetes mellitus (T1DM) has been associated to several cartilage and bone alterations including growth retardation, increased fracture risk, and bone loss. To determine the effect of long term diabetes on bone we used adult and aging Ins2 Akita mice that developed T1DM around 3-4 weeks after birth. Both Ins2 Akita and wild-type (WT) mice were analyzed at 4, 6, and 12 months to assess bone parameters such as femur length, growth plate thickness and number of mature and preapoptotic chondrocytes. In addition, bone microarchitecture of the cortical and trabecular regions was measured by microcomputed tomography and gene expression of Adamst-5, Col2, Igf1, Runx2, Acp5, and Oc was quantified by quantitative real-time polymerase chain reaction. Ins2 Akita mice showed a decreased longitudinal growth of the femur that was related to decreased growth plate thickness, lower number of chondrocytes and to a higher number of preapoptotic cells. These changes were associated with higher expression of Adamst-5, suggesting higher cartilage degradation, and with low expression levels of Igf1 and Col2 that reflect the decreased growth ability of diabetic mice. Ins2 Akita bone morphology was characterized by low cortical bone area (Ct.Ar) but higher trabecular bone volume (BV/TV) and expression analysis showed a downregulation of bone markers Acp5, Oc, and Runx2. Serum levels of insulin and leptin were found to be reduced at all-time points Ins2 Akita . We suggest that Ins2 Akita mice bone phenotype is caused by lower bone formation and even lower bone resorption due to insulin deficiency and to a possible relation with low leptin signaling.SFRH/BD/76873/2011/ SFRH/BD/76429/2011/ PEst-C/MAR/LA0015/2011info:eu-repo/semantics/publishedVersio

OCORRÊNCIA DA FORMIGA CORTADEIRA ATTA SEXDENS (L.) (HYMENOPTERA: FORMICIDAE) RELACIONADA A ESTRADAS NÃO-PAVIMENTADAS EM DUAS ÁREAS DO SEMIÁRIDO BRASILEIRO COM GRAUS DE PERTURBAÇÃO CONTRASTANTES

In the semiarid Brazilian Caatinga, we compared the occurrence of leaf-cutting ant nests (Atta sexdens) at two areas in Contendas do Sincorá, Bahia State: one single disturbed area subjected to cattle overgrazing (Fazenda Lagoa das Covas: FLC) and one protected area characterized by well-preserved patches of caatinga (Floresta Nacional Contendas do Sincorá: FNCS). We also tested if A. sexdens nests were more abundant near roads. No nest was observed in the FNCS, whereas 35 nests were recorded in the FLC (3.6 colonies ha-1). The number of A. sexdens nests clearly decreased with increasing road distance, which varied from zero to about 140 m. Nests were also observed on roads outside FLC and FNCS. We suggest that roads may be facilitating the expansion of A. sexdens range in the Caatinga vegetation at Contendas do Sincorá. We expect that A. sexdens presence will maintain or even increase the disturbing effects of cattle overgrazing on FLC vegetation. If A. sexdens also succeed to establish in FNCS, this protected area will experience a possible process of flora homogenization and impoverishment, favoring the establishment of plant species associated to anthropogenic disturbances. It is possible that other Caatinga areas are being subjected to the same process of Atta invasion favored by the establishment of paved and unpaved roads.Na Caatinga, semiárido brasileiro, nós comparamos a ocorrência de ninhos da formiga cortadeira (Atta sexdens) em duas áreas do município de Contendas do Sincorá, estado da Bahia: uma área perturbada por pecuária (Fazenda Lagoa das Covas: FLC), e uma protegida e com áreas preservadas de Caatinga (Floresta Nacional Contendas do Sincorá: FNCS). Nós também testamos se os ninhos de A. sexdens são mais abundantes próximos às estradas não pavimentadas. Nenhum ninho foi registrado na FNCS, em contraste, 35 ninhos foram registrados na FLC (3,6 colônias ha-1). O número de ninhos de A. sexdens claramente diminuiu com o aumento da distância da estrada, que variou de 0 a 140 m. Ninhos também foram observados nas estradas do lado de fora da FLC e da FNCS. Nós sugerimos que estradas podem estar facilitando a expansão de A. sexdens nas áreas de caatinga do município de Contendas do Sincorá. Nós esperamos que a presença de A. sexdens irá manter ou mesmo aumentar os efeitos dos distúrbios promovidos pelo gado na vegetação da FLC. Se o estabelecimento de A. sexdens na FNCS também for bem sucedido, nesta área protegida poderá ocorrer um processo de homogeneização e empobrecimento, favorecendo o estabelecimento de espécies de plantas associadas a perturbações antrópicas. É possível que outras áreas da Caatinga estejam sendo submetidas ao mesmo processo de invasão por Atta favorrecido por estradas pavimentadas e não-pavimentadas

3D biocomposites comprising marine collagen and silica-based materials inspired on the composition of marine sponge skeletons envisaging bone tissue regeneration

Ocean resources are a priceless repository of unique species and bioactive compounds with denouement properties that can be used in the fabrication of advanced biomaterials as new templates for supporting the cell culture envisaging tissue engineering approaches. The collagen of marine origin can be sustainably isolated from the underrated fish processing industry by-products, while silica and related materials can be found in the spicules of marine sponges and diatoms frustules. Aiming to address the potential of biomaterials composed from marine collagen and silica-based materials in the context of bone regeneration, four different 3D porous structure formulations (COL, COL:BG, COL:D.E, and COL:BS) were fabricated by freeze-drying. The skins of Atlantic cod (Gadus morhua) were used as raw materials for the collagen (COL) isolation, which was successfully characterized by SDS-PAGE, FTIR, CD, and amino acid analyses, and identified as a type I collagen, produced with a 1.5% yield and a preserved characteristic triple helix conformation. Bioactive glass 45S5 bioglass® (BG), diatomaceous earth (D.E.) powder, and biosilica (BS) isolated from the Axinella infundibuliformis sponge were chosen as silica-based materials, which were obtained as microparticles and characterized by distinct morphological features. The biomaterials revealed microporous structures, showing a porosity higher than 85%, a mean pore size range of 138â 315 µm depending on their composition, with 70% interconnectivity which can be favorable for cell migration and ensure the needed nutrient supply. In vitro, biological assays were conducted by culturing L929 fibroblast-like cells, which confirmed not only the non-toxic nature of the developed biomaterials but also their capability to support cell adhesion and proliferation, particularly the COL:BS biomaterials, as observed by calcein-AM staining upon seven days of culture. Moreover, phalloidin and DAPI staining revealed well-spread cells, populating the entire construct. This study established marine collagen/silica biocomposites as potential scaffolds for tissue engineering, setting the basis for future studies, particularly envisaging the regeneration of non-load-bearing bone tissues.This research was funded by European Union’s Horizon 2020 Framework Programme for Research and Innovation under the projects SponGES (H2020-BG-01-2015-679849)

Impact of UV-C radiation on melon peel

info:eu-repo/semantics/publishedVersio

Macro and microstructural characteristics of north Atlantic deep-sea sponges as bioinspired models for tissue engineering scaffolding

Sponges occur ubiquitously in the marine realm and in some deep-sea areas they dominate the benthic communities forming complex biogenic habitats â sponge grounds, aggregations, gardens and reefs. However, deep-sea sponges and spongegrounds are still poorly investigated with regards to biotechnological potential in support of a Blue growth strategy. Under the scope of this study, five dominant North Atlantic deep-sea sponges, were characterized to elucidate promising applications in human health, namely for bone tissue engineering approaches. Geodia barretti (Gb), Geodia atlantica (Ga), Stelletta normani (Sn), Phakellia ventilabrum (Pv), and Axinella infundibuliformis (Ai), were morphologically characterized to assess macro and microstructural features, as well as chemical composition of the skeletons, using optical and scanning electron microscopy, energy dispersive x-ray spectroscopy and microcomputed tomography analyses. Moreover, compress tests were conducted to determine the mechanical properties of the skeletons. Results showed that all studied sponges have porous skeletons with porosity higher than 68%, pore size superior than 149 mm and higher interconnectivity (>96%), thus providing interesting models for the development of scaffolds for tissue engineering. Besides that, EDS analyses revealed that the chemical composition of sponges, pointed that demosponge skeletons are mainly constituted by carbon, silicon, sulfur, and oxygen combined mutually with organic and inorganic elements embedded its internal architecture that can be important features for promoting bone matrix quality and bone mineralization. Finally, the morphological, mechanical, and chemical characteristics here investigated unraveled the potential of deep-sea sponges as a source of biomaterials and biomimetic models envisaging tissue engineering applications for bone regeneration.The authors would like to acknowledge the funding from the European Union Framework Program for Research and Innovation Horizon 2020 through project SponGES (H2020- BG-01-2015-679849) and from the Northern Portugal Regional Operational Program (NORTE2020), under the Portugal 2020 Partnership Agreement, through the Structured projects for R&D&I NORTE-01-0145-FEDER-000021 and NORTE-01-0145- FEDER-000023. JRX research was further supported by national funds through FCT Foundation for Science and Technology within the scope of UIDB/04423/2020 and UIDP/04423/2020, and CEECIND/00577/2018

Convolutamydine A and synthetic analogues have antinociceptive properties in mice

AbstractConvolutamydine A, an oxindole that originated from a marine bryozoan, has several biological effects. In this study, we aimed to investigate the antinociceptive effects of convolutamydine A and two new synthetic analogues.Convolutamydine A and the two analogues were given orally to assess their ability to induce antinociceptive effects. Formalin-induced licking response, acetic acid-induced contortions, and hot plate models were used to characterize the effects of convolutamydine A and its analogues.Convolutamydine A (4,6-bromo-3-(2-oxopropyl)-3-hydroxy-2-oxindole), compound 1 (3-(2-oxopropyl)-3-hydroxy-2-oxindole), and compound 2 (5-bromo-3-(2-oxopropyl)-3-hydroxy-2-oxindole) caused peripheral antinociceptive and anti-inflammatory effects in the acetic acid-induced contortions and the formalin-induced licking models. Supraspinal effects were also observed in the hot plate model and were similar to those obtained with morphine. The peripheral effects were not mediated by the cholinergic or opioid systems. The antinociceptive effects of convolutamydine A seem to be mediated by all three systems (cholinergic, opioid, and nitric oxide systems), and the mechanism of action of compounds 1 and 2 involved cholinergic and nitric oxide-mediated mechanisms. Convolutamydine A and its analogues (compounds 1 and 2) showed good antinociceptive ability after systemic administration in acute pain models. The antinociceptive action mediated by cholinergic, opioid, and nitric oxide systems could explain why convolutamydine A, compound 1, and compound 2 retained their antinociceptive effects. The doses used were similar to the doses of morphine and were much lower than that of acetylsalicylic acid, the classical analgesic and anti-inflammatory drug.In conclusion, convolutamydine A and the two analogues demonstrated antinociceptive effects comparable to morphine's effects