Il trattamento con topiramato protegge i topi APOE-KO dall’insorgenza di danno renale senza modificare i livelli dei lipidi plasmatici

Il topiramato e\u300 un farmaco impiegato nel trattamento dell\u2019epilessia e prescritto anche nella profilassi dell\u2019emicrania che si caratterizza per i molteplici meccanismi d\u2019azione. Diversi studi indicano che il trattamento con topiramato promuove la riduzione del peso corporeo e riduce moderatamente i livelli dei lipidi plasmatici e la glicemia. In considerazione di questi effetti metabolici positivi si e\u300 deciso di valutare se il trattamento con topiramato potesse modulare lo sviluppo di aterosclerosi e al tempo stesso avere effetti protettivi sugli organi bersaglio di condizioni dismetaboliche. Trenta topi apoE-KO sono stati distribuiti in tre gruppi sperimentali e alimentati per 12 settimane con una dieta ad elevato contenuto lipidico (controllo), oppure con la stessa dieta addizionata con topiramato allo 0.125% o allo 0.25%. Il peso corporeo e il consumo di cibo e acqua sono stati monitorati durante tutto lo studio. E\u300 stata inoltre misurata la concentrazione dei lipidi plasmatici e la glicemia, ed e\u300 stato effettuato un test di tolleranza al glucosio. Lo sviluppo di aterosclerosi e\u300 stato valutato nell\u2019intera aorta e nel seno aortico. Sono state inoltre condotte indagini istologiche su fegato, rene e tessuto adiposo. Il trattamento con topiramato non ha influenzato l\u2019aumento di peso corporeo o il consumo di cibo. La tolleranza al glucosio e la concentrazione lipidica plasmatica sono risultati comparabili tra i gruppi, cosi\u300 come lo sviluppo di aterosclerosi. Il trattamento non ha inoltre alterato l\u2019istologia del fegato e del tessuto adiposo. A livello renale, il trattamento con topiramato ha invece ridotto l\u2019insorgenza di lipidosi glomerulare in modo dose-dipendente, riducendo l\u2019accumulo di cellule schiumose e l\u2019espressione di marcatori di infiammazione. Inoltre, anche i livelli plasmatici di urea sono risultati ridotti in seguito al trattamento. In conclusione, i risultati ottenuti indicano che il trattamento con topiramato non influenza lo sviluppo di aterosclerosi, ma preserva struttura e funzionalita\u300 renale. Il topiramato potrebbe pertanto essere preso in considerazione in studi di riposizionamento farmacologico per il trattamento della lipidosi glomerulare

Recombinant human osteopontin expressed in Nicotiana benthamiana stimulates osteogenesis related genes in human periodontal ligament cells.

Tissue engineering aims to utilise biologic mediators to facilitate tissue regeneration. Several recombinant proteins have potential to mediate induction of bone production, however, the high production cost of mammalian cell expression impedes patient access to such treatments. The aim of this study is to produce recombinant human osteopontin (hOPN) in plants for inducing dental bone regeneration. The expression host was Nicotiana benthamiana using a geminiviral vector for transient expression. OPN expression was confirmed by Western blot and ELISA, and OPN was purified using Ni affinity chromatography. Structural analysis indicated that plant-produced hOPN had a structure similar to commercial HEK cell-produced hOPN. Biological function of the plant-produced hOPN was also examined. Human periodontal ligament stem cells were seeded on an OPN-coated surface. The results indicated that cells could grow normally on plant-produced hOPN as compared to commercial HEK cell-produced hOPN determined by MTT assay. Interestingly, increased expression of osteogenic differentiation-related genes, including OSX, DMP1, and Wnt3a, was observed by realtime PCR. These results show the potential of plant-produced OPN to induce osteogenic differentiation of stem cells from periodontal ligament in vitro, and suggest a therapeutic strategy for bone regeneration in the future

Chemotherapy induces Notch1-dependent MRP1 up-regulation, inhibition of which sensitizes breast cancer cells to chemotherapy

Background Multi-drug Resistance associated Protein-1 (MRP1) can export chemotherapeutics from cancer cells and is implicated in chemoresistance, particularly as is it known to be up-regulated by chemotherapeutics. Our aims in this study were to determine whether activation of Notch signalling is responsible for chemotherapy-induced MRP1 expression Notch in breast cancers, and whether this pathway can be manipulated with an inhibitor of Notch activity. Methods MRP1 and Notch1 were investigated in 29 patients treated with neoadjuvant chemotherapy (NAC) for breast cancer, using immunohistochemistry on matched biopsy (pre-NAC) and surgical samples (post-NAC). Breast epithelial cell cultures (T47D, HB2) were treated with doxorubicin in the presence and absence of functional Notch1, and qPCR, siRNA, Western blots, ELISAs and flow-cytometry were used to establish interactions. Results In clinical samples, Notch1 was activated by neoadjuvant chemotherapy (Wilcoxon signed-rank p < 0.0001) and this correlated with induction of MRP1 expression (rho = 0.6 p = 0.0008). In breast cell lines, doxorubicin induced MRP1 expression and function (non-linear regression p < 0.004). In the breast cancer line T47D, doxorubicin activated Notch1 and, critically, inhibition of Notch1 activation with the γ-secretase inhibitor DAPT abolished the doxorubicin-induced increase in MRP1 expression and function (t-test p < 0.05), resulting in enhanced cellular retention of doxorubicin and increased doxorubicin-induced apoptosis (t-test p = 0.0002). In HB2 cells, an immortal but non-cancer derived breast cell line, Notch1-independent MRP1 induction was noted and DAPT did not enhance doxorubicin-induced apoptosis. Conclusions Notch inhibitors may have potential in sensitizing breast cancer cells to chemotherapeutics and therefore in tackling chemoresistance

Phosphoproteomics Identifies Oncogenic Ras Signaling Targets and Their Involvement in Lung Adenocarcinomas

Ras is frequently mutated in a variety of human cancers, including lung cancer, leading to constitutive activation of MAPK signaling. Despite decades of research focused on the Ras oncogene, Ras-targeted phosphorylation events and signaling pathways have not been described on a proteome-wide scale.By functional phosphoproteomics, we studied the molecular mechanics of oncogenic Ras signaling using a pathway-based approach. We identified Ras-regulated phosphorylation events (n = 77) using label-free comparative proteomics analysis of immortalized human bronchial epithelial cells with and without the expression of oncogenic Ras. Many were newly identified as potential targets of the Ras signaling pathway. A majority (∼60%) of the Ras-targeted events consisted of a [pSer/Thr]-Pro motif, indicating the involvement of proline-directed kinases. By integrating the phosphorylated signatures into the Pathway Interaction Database, we further inferred Ras-regulated pathways, including MAPK signaling and other novel cascades, in governing diverse functions such as gene expression, apoptosis, cell growth, and RNA processing. Comparisons of Ras-regulated phosphorylation events, pathways, and related kinases in lung cancer-derived cells supported a role of oncogenic Ras signaling in lung adenocarcinoma A549 and H322 cells, but not in large cell carcinoma H1299 cells.This study reveals phosphorylation events, signaling networks, and molecular functions that are regulated by oncogenic Ras. The results observed in this study may aid to extend our knowledge on Ras signaling in lung cancer

Toward osteogenic differentiation of marrow stromal cells and in vitro production of mineralized extracellular matrix onto natural scaffolds

Uncorrected proofTissue engineering has emerged as a new interdisciplinary field for the repair of various tissues, restoring their functions by using scaffolds, cells, and/or bioactive factors. A temporary scaffold acts as an extracellular matrix analog to culture cells and guide the development of new tissue. In this chapter, we discuss the preparation of naturally derived scaffolds of polysaccharide origin, the osteogenic differentiation of mesenchymal stem cells cultured on biomimetic calcium phosphate coatings, and the delivery of biomolecules associated with extracellular matrix mineralization

Relation mining over a corpus of scientific literature

The amount of new discoveries (as published in the scientific literature) in the area of Molecular Biology is currently growing at an exponential rate. This growth makes it very difficult to filter the most relevant results, and the extraction of the core information, for inclusion in one of the knowledge resources being maintained by the research community, becomes very expensive. Therefore, there is a growing interest in text processing approaches that can deliver selected information from scientific publications, which can limit the amount of human intervention normally needed to gather those results. This paper presents and evaluates an approach aimed at automating the process of extracting semantic relations (e.g. interactions between genes and proteins) from scientific literature in the domain of Molecular Biology. The approach, using a novel dependency-based parser, is based on a complete syntactic analysis of the corpus