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- Lower melanoma pulmonary metastatic burden in obese mice: role of FGF-21Publication . Fonseca, Magda; Soares, Raquel; Coelho, PedroObesity is a risk factor for malignant melanoma. The lungs are main target organs for metastization and their immune response is a key modulator of this mechanism. The concept that the metastatic potential of some types of cancer is reduced or inhibited by obesity, known as the obesity paradox, drives major concerns on the prognosis of metastasized patients. The aim of this study was to investigate how high-fat diet (HFD)-induced obesity affects melanoma metastization. C57Bl6/J mice were fed with HFD or standard diet for 180 days and inoculated intravenously with B16F10 melanoma cells. Upon 21 days of inoculation, lung tissue of overweight and lean mice was assessed for histology and immunohistochemistry assays. Adipokine antibody arrays were performed in mice serum. In vitro RAW 264.7 macrophage cultures were established and incubated with FGF-21 and/or lipopolysaccharide (LPS). Conditioned media was added to B16F10 cells for viability quantification. HFD-fed mice presented a reduced number of metastases with lower proliferative rates. The high content of inflammatory foci observed in noninoculated obese mice was significantly decreased upon B16F10 inoculation, concurrent with a slight fibrosis reduction. Plasma levels of fibroblast growth factor-21 (FGF-21), an endocrine regulator, were elevated in noninoculated HFD mice and the expression of FGF receptor 1 (FGFR-1) was significantly upregulated after inoculation. FGF-21 reduced melanoma viability in LPS-stimulated macrophages. Altogether, these findings suggest that higher amounts of FGF-21 are able to counterbalance the proinflammatory effects associated with obesity, protecting the lungs from melanoma metastization.
- The effect of xanthohumol-supplemented beer on angiogenic and inflammatory in vivo assaysPublication . Costa, R.; Duarte, D.; Taveira, T.; Pirraco, A.; Coelho, Pedro; Guardão, L.; Soares, R.; Negrão, R.Angiogenesis is a process by which new blood vessels are formed from pre-existing ones and can occur in adulthood during tissue regeneration. This process is closely related with inflammatory conditions. Due to their notable biological activities, phenolic compounds have an important role in nutrition and human health. Special attention has been given to xanthohumol (XN), a compound present in hops and beer [3]. Our purpose was to evaluate the effects of a XN-supplemented beer on angiogenesis and inflammation, in a rat skin-wound healing process. Six week old Wistar male rats drank water, 5% solution ethanol, stout beer or stout beer supplemented with 10 mg XN/L, during 4 weeks. Then, two incisions were created on the dorsal skin. Animals continued beverages consumption for 7 days. The number of vessels in the incision area (vWF staining), NO release, NAG activity and IL-1β content in serum were measured. Analyses of serum biochemical markers of hepatic function (AST, ALT and ALP activities) and of metabolic status (glucose, triglycerides, cholesterol, VLDL, LDL and HDL) were evaluated. GSH/GSSG plasma levels were measured in plasma by HPLC. Statistical differences were evaluated by ANOVA followed by the Bonferroni test. Differences were considered significant whenever p< 0.05. The consumption of XN-supplemented beer led to decreased number of vessels in the wound area, and decreased NAG activity, NO and IL-1β content in the serum when compared to stout beer. Plasma biochemical markers of hepatic function and metabolic status did not change with the distinct beverages consumption. GSH/GSSG ratio increased with ethanol and beer consumption. Altogether, these findings suggest that gastrointestinal administration of XN-supplemented beer may affect the wound healing process, in what concerns inflammation and angiogenesis, without hepatotoxic effects. Ethanol consumption seems to improve plasma anti-oxidant protection. These health-promoting properties of XN can be interesting to the brewing community.
- Distúrbios alimentares – anorexia: da auto-imagem às atitudes e comportamentosPublication . Fernandes, Rúben; Reis, AC.; Esteves-Pinto, A.; Fonte, R.; Coelho, Pedro; Prudêncio, CristinaSão ainda escassos os estudos sobre distúrbios alimentares em alunos do ensino universitário em Portugal. Estudos mais recentes indicam que poderá existir uma predisposição genética para a anorexia, no entanto, os fatores ambientais são os que apresentam um papel determinante, em particular factores sócio-económicos, psicológicos, biológicos entre outros. Entre esses diversos factores, sabe-se que a auto-imagem pode relacionar-se como múltiplos distúrbios alimentares como a anorexia e bulimia.
- Potentional radiosensitizer effect of TUDCA in a obesity model of brain tumor cellsPublication . Silva, Liliana; Almeida, Joana; Coelho, Pedro; Faria, Isabel; Monteiro, Armanda; Soares, Raquel; Vieira, Mónica; Prudêncio, Cristina; Fernandes, RúbenObesity may play an important role in the biology of seve ral types of cancer, but the correlation with glioma Is still not very well defined. Former studies indicated that obesity may be related with an decreased resistance to radiation and increased redox status in brain tumors. Since radiothetapy is the most commonly treatment modality used in this type of tumor, we creale a new model of experiments to determinate the influence of obesity in glioma cells [n the presence of radiation with an imbalance of redox status, BC3H1 glioma cells were treated with t-BOOH (150~M), TUDCA (25~M) and a mix of t-BOOH and TUOCA{150~M and 25~M respectively) in serum-free OMEM or conditioned media (CM) from differentiated 3T3-L 1 adj pocytes. Afterwards the cells were irradiated with a total dose of 2 Gy. Subsequently BC3H1 viability was evaluated, by MTT assay, after 4 and 12 hours. We observed an increase in viability In all cells treated solely with 3T3-L 1 eM. Interestingly, in the presence of CM plus TUDCA or t-BOOH, the viability of 6C3H1 was inferior of TUOCA or t~BOOH treatments alone, this effect was independent of irradia tion. After 12 hours the I/iability of the glioma cells was significantly higher on irradiated ceUs treated only with eM, this effect was not yet observed at the 4 hours time point But, in the presence of mix of t~BOOH and TUDCA, with eM and irradiation the cells viability decrea se significanUy. The 3T3-L 1 Me increase (he cell viabrlity in the presence of radiation or not, after 12 hours expose" But in the presence of oxidatIve inducer and, In specially, with the antioxidant TUDCA, the BC3Hi viability significantly decrease. So, we observed a potential radiosensitfzer effect of TUDCA in BC3H1 in the presence of 3T3-L1 adipocytes.
- Evaluation of the probiotic potential of a strain of Saccharomyces cerevisiaePublication . Areal-Hermida, Lara; Pichardo-Gallardo, Ángeles; Coelho, Pedro; Prudêncio, Cristina; Sieiro, CarmenAccording to the World Health Organization (WHO) and the Food and Agriculture Organization of the United Nations (FAO), probiotics are living microorganisms that, when administered in appropriate quantities, can confer a beneficial effect on the health of the host. Probiotic potential has been demonstrated especially for many strains of different species of bacteria. However, there are fewer strains of yeast for which their probiotic properties have been studied, despite their advantages, which include the fact that they are not affected by antibacterial antibiotics or their inability to disperse antibiotic resistance genes. As a result, there is a growing interest in characterizing new yeasts as probiotics. The aim of this study was to evaluate in our laboratories the probiotic potential of a strain of Saccharomyces cerevisiae var. boulardii (the main species marketed as a probiotic so far), to compare it with that of other yeasts. Strain identification was carried out by analyzing the ITS and D1/D2 regions of the rDNA. Regarding the ability of the strain to survive at 37ºC and resist gastrointestinal conditions, the strain showed 100 % viability at 37ºC and between 95-100 % in synthetic gastric and duodenal juices (pH 2-7.5, 0.3-10 % bile salts, 0.3 % pepsin and 0.1 % pancreatin). In addition, the selfaggregation and hydrophobicity properties shown by the strain allowed inferring the ability to adhere to the intestine, which was confirmed in Caco-2 cells. Additionally, the strain presented other properties of interest for probiotics, including a high anti-oxidant capacity and pathogen coaggregation, as well as a variable cytotoxic activity against different tumor cell lines.
- A hiperglicemia e o secretoma de adipócitos alteram o padrão de crescimento de micobactérias in vitroPublication . Fernandes, Rúben; Bronze, M.; Pereira, C.; Coelho, Pedro; Prudêncio, Cristina
- Adipocyte secretome increases radioresistance of malignant melanocytes by improving cell survival and decreasing oxidative statusPublication . Coelho, Pedro; Silva, Liliana; Faria, Isabel; Vieira, Mónica; Monteiro, Armanda; Pinto, Gabriela; Prudêncio, Cristina; Fernandes, Rúben; Soares, RaquelRadiotherapy is a treatment option for the majority of malignancies. However, because melanoma is known to be radioresistant, the use of ionizing radiation as an adjuvant therapy in cutaneous melanoma patients is ineffective. Obesity has now been recognized as a risk factor for melanoma. High adiposity is generally associated with a more pro-oxidative status. Oxidative stress is a major player in radiation therapy and also a common link between obesity and cancer. Several adipocyte-released proteins are known to have a role in controlling cellular growth and pro-survival signaling. For that reason, we investigated the influence of 3T3-L1 mature adipocyte secretome in B16-F10 malignant melanocyte radiosensitivity. We evaluated B16-F10 cell survival and redox homeostasis when exposed to four daily doses of ionizing radiation (2 Gy per day) up to a total of 8 Gy in a medical linear accelerator. B16-F10 melanocytes exhibited slight alterations in survival, catalase activity, nitrative stress and total oxidant concentration after the first 2 Gy irradiation. The motility of the melanocytes was also delayed by ionizing radiation. Subsequent irradiations of the malignant melanocytes led to more prominent reductions in overall survival. Remarkably, 3T3-L1 adipocyte-secreted molecules were able to increase the viability and migration of melanocytes, as well as lessen the pro-oxidant burden induced by both the single and cumulative X-ray doses. In vitro adipocyte-released factors protected B16-F10 malignant melanocytes from both oxidative stress and loss of viability triggered by radiation, enhancing the radioresistant phenoyype of these cells with a concomitant activation of the AKT signaling pathway These results both help to elucidate how obesity influences melanoma radioresistance and support the usage of conventional medical linear accelerators as a valid model for the in vitro radiobiological study of tumor cell lines.
- Adipocyte-released factors enhance melanocyte’s proliferation and motilityPublication . Fernandes, Rúben; Coelho, Pedro; Almeida, Joana; Prudêncio, Cristina; Soares, RaquelObesity, favored by the modern lifestyle, acquired epidemic proportions nowadays. Obesity has been associated with various major causes of death and morbidity including malignant neoplasms. Cutaneous melanoma incidence rates have also been increasing uring the last four decades in several countries. Obesity involvement in melanoma etiology has been recognized, but the implicated mechanisms remain unclear. We propose to address the above relationship and investigate the mechanism interplaying between obesity and an increased risk of melanoma onset.
- Protein structural alterations in diabetic cavernosal tissue - their role in erectile dysfunction progressionPublication . Castela, A.; Soares, R.; Gomes, P.; Coelho, Pedro; Fernandes, RubenErectile dysfunction (ED) is one of the most prevalent complications in diabetic men. Hyperglicemia contributes to increased oxidative stress (OS) in diabetic corpus cavernosum (CC), promoting alterations in cavernosal cellular components. However, it remains unclear the mechanisms by which OS induces modifi cations in diabetic penile tissue with the progression of diabetes and its role in the devel opment of ED. We intended to evaluate/quantify CC protein structural modifi cation caused by OS in an early and late stage of diabetes.
- Book of abstracts 4th Meeting on Medicinal Biotechnology (4EBtM)Publication . Costa, Ana Rita; Dias, Ana Rita; Prudêncio, Cristina; Borges, Cristina; Teixeira, Dulce; Almeida, Joana; Vieira, Mónica; Coelho, Pedro; Ferraz, Ricardo; Cunha, SofiaThese meetings have been held once a year since 2015 and have played an important role as a point of contact among several professionals and students in Medicinal Biotechnology. Like the Medicinal Biotechnology field itself, these meetings have also been expanding, not only in the number of participants, but also in their geographical origin. Therefore, it is our goal to act as an interface between students and biotechnology companies/researchers, as well as to increasingly promote networking, projects and collaborations within this field for the upcoming years.