Diana Valente

Dr. Diana Valente


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 April 2017 in Seminars in Cancer Biology
Verified
Journal Article
Closed access
Sara GranjaSara Granja
Sara Granja
DVDiana Valente
Diana Valente
Odília QueirósOdília Queirós
Odília Queirós
FBFatima Baltazar
Fatima Baltazar

30 June 2013 in Journal of Bioenergetics and Biomembranes
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Journal Article
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PDF file
DVDiana Valente
Diana Valente
FBFatima Baltazar
Fatima Baltazar
RMRoxana Moreira
Roxana Moreira
Odília QueirósOdília Queirós
Odília Queirós

17 August 2022 in Colloids and Surfaces B: Biointerfaces
Verified
Journal Article
Closed access
Ana OliveiraAna Oliveira
Ana Oliveira
DVDiana Valente
Diana Valente
HMHelena Moreira
Helena Moreira
Manuela PintadoManuela Pintado
Manuela Pintado
PCPatrícia S. Costa
Patrícia S. Costa

18 June 2021 in Pharmaceuticals
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Journal Article
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FTFrancisca S. Teixeira
Francisca S. Teixeira
SVSusana Vidigal
Susana Vidigal
Lígia PimentelLígia Pimentel
Lígia Pimentel
PCPaula T. Costa
Paula T. Costa
DVDiana Valente
Diana Valente
Luis Miguel Rodríguez-AlcaláLuis Miguel Rodríguez-Alcalá
Luis Miguel Rodríguez-Alcalá
The unstoppable growth of human population that occurs in parallel with all manufacturing activities leads to a relentless increase in the demand for resources, cultivation land, and energy. In response, currently, there is significant interest in developing strategies to optimize any available resources and their biowaste. While solutions initially focused on recovering biomolecules with applications in food, energy, or materials, the feasibility of synthetic biology in this field has been demonstrated in recent years. For instance, it is possible to genetically modify Saccharomyces cerevisiae to produce terpenes for commercial applications (i.e., against malaria or as biodiesel). But the production process, similar to any industrial activity, generates biowastes containing promising biomolecules (from fermentation) that if recovered may have applications in different areas. To test this hypothesis, in the present study, the lipid composition of by-products from the industrial production of β-farnesene by genetically modified Saccharomyces cerevisiae are studied to identify potentially bioactive compounds, their recovery, and finally, their stability and in vitro bioactivity. The assayed biowaste showed the presence of triterpenes, phytosterols, and 1-octacosanol which were recovered through molecular distillation into a single fraction. During the assayed stability test, compositional modifications were observed, mainly for the phytosterols and 1-octacosanol, probably due to oxidative reactions. However, such changes did not affect the in vitro bioactivity in macrophages, where it was found that the obtained fraction decreased the production of TNF-α and IL-6 in lipopolysaccharide (LPS)-induced inflammation.

9 February 2021 in Pharmaceutics
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Journal Article
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DVDiana Valente
Diana Valente
BSBárbara Sousa
Bárbara Sousa
Fernando SchmittFernando Schmitt
Fernando Schmitt
FBFatima Baltazar
Fatima Baltazar
Odília QueirósOdília Queirós
Odília Queirós
The reverse pH gradient is a major feature associated with cancer cell reprogrammed metabolism. This phenotype is supported by increased activity of pH regulators like ATPases, carbonic anhydrases (CAs), monocarboxylate transporters (MCTs) and sodium–proton exchangers (NHEs) that induce an acidic tumor microenvironment, responsible for the cancer acid-resistant phenotype. In this work, we analyzed the expression of these pH regulators and explored their inhibition in breast cancer cells as a strategy to enhance the sensitivity to chemotherapy. Expression of the different pH regulators was evaluated by immunofluorescence and Western blot in two breast cancer cell lines (MDA-MB-231 and MCF-7) and by immunohistochemistry in human breast cancer tissues. Cell viability, migration and invasion were evaluated upon exposure to the pH regulator inhibitors (PRIs) concanamycin-A, cariporide, acetazolamide and cyano-4-hydroxycinnamate. Additionally, PRIs were combined with doxorubicin to analyze the effect of cell pH dynamic disruption on doxorubicin sensitivity. Both cancer cell lines expressed all pH regulators, except for MCT1 and CAXII, only expressed in MCF-7 cells. There was higher plasma membrane expression of the pH regulators in human breast cancer tissues than in normal breast epithelium. Additionally, pH regulator expression was significantly associated with different molecular subtypes of breast cancer. pH regulator inhibition decreased cancer cell aggressiveness, with a higher effect in MDA-MB-231. A synergistic inhibitory effect was observed when PRIs were combined with doxorubicin in the breast cancer cell line viability. Our results support proton dynamic disruption as a breast cancer antitumor strategy and the use of PRIs to boost the activity of conventional therapy.

6 August 2024 in Molecules
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Journal Article
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MCMaria Leonor Teixeira Pinto de Castro
Maria Leonor Teixeira Pinto de Castro
Joao SilvaJoao Silva
Joao Silva
DVDiana Valente
Diana Valente
AMAdriana Rodrigues Machado
Adriana Rodrigues Machado
TRTânia Ribeiro
Tânia Ribeiro
SSSara Silva
Sara Silva
The skin is the largest organ in the human body and serves multiple functions such as barrier protection and thermoregulation. The maintenance of its integrity and healthy structure is of paramount importance. Accordingly, technological advances in cosmetic sciences have been directed towards optimizing these factors. Plant-derived ingredients have been explored for their bioactivity profiles and sustainable sources. Grape by-products contain a group of bioactive molecules that display important biological activities. Nonetheless, many of these molecules (e.g., phenolic compounds) are unstable and susceptible to degradation. So, their encapsulation using nano/microsystems (i.e., microdispersions) has been explored as a promising solution. In this work, two grape seed extracts were obtained, one from a single grape variety (GSE-Ov) and another from a mix of five grape varieties (GSE-Sv). These extracts were analysed for their antioxidant and antimicrobial activities, as well as their chemical composition and molecular structure. The extract that showed the most promising properties was GSE-Ov with a DPPH IC50 of 0.079 mg mL−1. This extract was encapsulated in soy lecithin microdispersions coated with pectin, with an encapsulation efficiency of 88.8%. They showed an in vitro release of polyphenols of 59.4% during 24 h. The particles displayed a zeta potential of −20.3 mV and an average diameter of 13.6 µm. Microdispersions proved to be safe under 5 and 2.5 mg mL−1 in HaCaT and HDF cell models, respectively. Additionally, they demonstrated anti-inflammatory activity against IL-1α when tested at 2 mg mL−1. This work enabled the valorisation of a by-product from the wine industry by using natural extracts in skincare products.