Fátima Martel

University of Porto | UP · Faculty of Medicine

Human malignancies are one of the major health-related issues throughout the world and are anticipated to rise in the future. Despite huge investments made in anticancer drug development, limited success has been obtained and the average number of FDA approvals per year is declining. So, an increasing interest in drug repurposing exists. Metformin...

Sweet cherry (Prunus avium L.) is among the most valued fruits due to its organoleptic properties and nutritional worth. Cherry stems are rich in bioactive compounds, known for their anti-inflammatory and antioxidant properties. Innumerable studies have indicated that some bioactive compounds can modulate sugar absorption in the small intestine. In...

Atypical antipsychotics (AAPs) are commonly prescribed drugs in the treatment of schizophrenia, bipolar disorder and other mental diseases with psychotic traits. Although the use of AAPs is associated with beneficial effects in these patients, they are also associated with undesired metabolic side effects, including metabolic syndrome (MetS). MeS i...

Inflammatory bowel disease (IBD) is a group of chronic and life-threating inflammatory diseases of the gastrointestinal tract. The active intestinal absorption of bile salts is reduced in IBD, resulting in higher luminal concentrations of these agents that contribute to the pathophysiology of IBD-associated diarrhea. Butyrate (BT) is a short-chain...

Butyrate (BT) is important in the prevention and inhibition of colorectal cancer (CRC). Inflammatory bowel disease, a risk factor for CRC, is associated with higher levels of proinflammatory cytokines and bile acids. The aim of this work was to investigate the interaction of these compounds in inhibiting BT uptake by Caco-2 cells, as a mechanism co...

Phenolic acids are recognized as chemopreventive and chemotherapeutic agents. Altered glucose and glutamine metabolism are recognized hallmarks of cancer cells. We aimed to test the influence of phenolic acids on glucose and glutamine cellular uptake by a breast (MCF-7) and a pancreatic (AsPC-1) cancer cell line. Several phenolic acids (caffeic, fe...

During pregnancy, the body undergoes a great amount of changes in order to support a healthy developing fetus. In this context, maternal dietary supplementation is widely encouraged to provide adequate nutrition for the newborn. In the past few years, studies have emerged highlighting the benefits of polyphenols intake during pregnancy. Indeed, des...

Diabetes mellitus, a chronic metabolic disease with an alarming global prevalence, is associated with several serious health threats, including cardiovascular diseases. Current diabetes treatments have several limitations and disadvantages, creating the need for new effective formulations to combat this disease and its associated complications. Thi...

Towards the end of 2019 in Wuhan, suspicions of a new dangerous virus circulating in the air began to arise. It was the start of the world pandemic coronavirus disease 2019 (COVID-19). Since then, considerable research data and review papers about this virus have been published. Hundreds of researchers have shared their work in order to achieve a b...

Breast cancer is the most common malignancy among women worldwide and is also the leading cause of cancer-related death in this gender. Type 2 diabetes mellitus (T2D) is one of the most common chronic diseases worldwide. There is a positive association between breast cancer and T2D, especially evident for triple-negative breast cancer (TNBC). In th...

Moderate coffee ingestion has been associated with a decrease in type 2 diabetes risk, mainly due to its richness in chlorogenic acids (CGA). To explore this, extracts of green beans, roasted beans, and silverskin were prepared by aqueous ultrasound-assisted extraction and characterized by a reversed-phase high-performance liquid chromatography-pho...

Background Breast cancer is a major cause of cancer-related mortality in women worldwide. Triple-negative breast cancer presents an aggressive behavior and a poor response to therapeutic. Cancer progression is associated with reprogramming of metabolic pathways for glutamine, glucose and folic acid. Methods In this study, we characterized the anti...

Background and objective: Cannabidiol, one of the main components of the Cannabis sativa plant, is a non-psychotropic cannabinoid that has recently drawn the attention of researchers and clinicians for its potential therapeutic applications. In this systematic review, we aim to describe the possible effects of cannabidiol in appetite and body weig...

Coffee is one of the most consumed products in the world, and its by-products are mainly discarded as waste. In order to solve this problem and in the context of a sustainable industrial attitude, coffee by-products have been studied concerning their chemical and nutritional features for a potential application in foodstuffs or dietary supplements....

In vitro studies have demonstrated that fluoxetine, a commonly used antidepressant drug, can modulate the activity of K⁺ channels. In the present study, we investigated the in vivo effect of acute and sub-chronic treatment of rats with fluoxetine on K⁺ renal transport. Furthermore, OK cells, a kidney epithelial cell line, were used in order to eval...

Extravillous trophoblasts (EVTs) are a key cell type involved in placentation. Aspartame is an artificial sweetener with a widespread use. In rodents, aspartame ingestion during pregnancy was found to cause a reduction in placental and fetal weights, but its effect in placentation at a cellular level has not been studied. Aspartame is completely hy...

Inflammatory bowel disease (IBD) is a group of chronic and life-threating inflammatory diseases of the gastrointestinal tract. The active intestinal absorption of bile salts is reduced in IBD, resulting in higher luminal concentrations of these agents that contribute to the pathophysiology of IBD-associated diarrhea. Butyrate is a short-chain fatty...

This study investigates the possibility of valorizing coffee silverskin through the recovery of its bioactive compounds using a sustainable extraction method that could be industrially applied. For that, aqueous extracts were prepared using ultrasonic-assisted extraction (laboratorial scale) and, for comparison, a scale-up of the process was develo...

Breast cancer constitutes the most incident cancer and one of the most common causes of cancer-related death. “Glutamine addiction”, an important metabolic feature of cancer cells, is dependent on supply of this amino acid from external sources. In this study, the effect of several polyphenols (catechin, epicatechin, EGCG, catechin:lysine, naringen...

After the serendipitous discovery of cisplatin, a platinum-based drug with chemotherapeutic effects, an incredible amount of research in the area of coordination chemistry has been produced. Other transition metal compounds were studied, and several new relevant metallodrugs have been synthetized in the past few years. This review is focused on coo...

Extravillous trophoblasts (EVTs) are the main participants in the process of placentation, an early process critical for placental growth and function involving an adequate invasion and complete remodelling of the maternal spiral arteries during early pregnancy. An increase in oxidative stress during pregnancy is associated with the onset and progr...

Type 2 diabetes mellitus (T2DM) is linked to an increased risk of breast cancer. We aimed to investigate how T2DM-associated characteristics (high levels of glucose, insulin, leptin, inflammatory mediators and oxidative stress) influence breast cancer carcinogenesis, in DMBA-treated (MCF-12ADMBA) and non-treated breast epithelial (MCF-12A) cell lin...

Coffee silverskin (CS) is the major by-product of coffee roasting and a source of caffeine and chlorogenic acids (CGA), recognized modulators of sugar metabolism. In this work, the effect of a CS extract on glucose and fructose uptake by human intestinal epithelial (Caco-2) cells was ascertained. Freeze-dried aqueous extracts were prepared using an...

Aims Type 2 diabetes mellitus (T2DM) is a risk factor for breast cancer initiation and progression. Glutamine (GLN) is a critical nutrient for cancer cells. The aim of this study was to investigate the effect of T2DM-associated compounds upon GLN uptake by breast cancer cells. Main methods The in vitro uptake of ³H-GLN by breast cancer (MCF-7 and...

Cancer cells are metabolically reprogrammed to support their high rates of proliferation, continuous growth, survival, invasion, metastasis, and resistance to cancer treatments. Among changes in cancer cell bioenergetics, the role of glutamine metabolism has been receiving increasing attention. Increased glutaminolysis in cancer cells is associated...

Background Obesity is a disease characterized by excessive accumulation of body fat, weight gain, increased glycemia and lipid profile. These alterations produce deleterious health effects through time. Faced with the growing search for coadjuvant options for obesity and its associated comorbidities, bioactive compounds such as flavonoids are an in...

Obesity and type 2 diabetes mellitus (T2DM) associate with increased incidence and mortality from many cancers, including breast cancer. The mechanisms involved in this relation remain poorly understood. Our study aimed to investigate the in vitro effect of high levels of glucose, insulin, leptin, TNF-α, INF-γ and oxidative stress (induced with ter...

Background Fructose is a hexose sugar found naturally in our diet and excessive fructose consumption has been documented in humans over the last decades. Fructose absorption in the small intestine is a highly regulated process and GLUT5 plays an essential role in this process, but GLUT2 is also involved. Methods In this review, we will describe th...

Cisplatin has demonstrated extraordinary anticancer activity against a variety of solid tumors. However, its clinical efficacy is contrasted by its toxicity profile. Having in mind the need to reduce the toxicity, promote a sustained release and enhance the body-circulation time of cisplatin, herein novel nanocarriers consisting of core-shell silic...

The antioxidant potential and phenolic profile of infusions prepared with cherry stems from different commercial brands were studied. The phenolic profile of each infusion was characterized by UHPLC-ESI-QTOF-MS and 44 phenolic compounds belonging to eight distinct classes (hydroxybenzoic acids, hydroxycinnamic acids, phenylpropanoic acids, flavan-3...

Purpose Metabolic syndrome (MS) is a major public health issue worldwide and fructose consumption has been associated with MS development. Recently, we showed that the dietary polyphenol chrysin is an effective inhibitor of fructose uptake by human intestinal epithelial cells. Therefore, our aim was to investigate if chrysin interferes with the dev...

Doxorubicin is one of the most widely used anti-cancer drugs, but side effects and selectivity problems create a demand for alternative drug delivery systems. Herein we describe a hybrid magnetic nanomaterial as a pH-dependent doxorubicin release carrier. This nanocarrier comprises magnetic iron oxide cores with a diameter of 10 nm, enveloped in a...

Reprogramming of cellular energy metabolism is widely accepted to be a cancer hallmark. The deviant energetic metabolism of cancer cells-known as the Warburg effect-consists in much higher rates of glucose uptake and glycolytic oxidation coupled with the production of lactic acid, even in the presence of oxygen. Consequently, cancer cells have high...

Offspring of dams exposed to excess folic acid during the perigestational period have been shown by us to be predisposed to metabolic dysfunction revealed by hyperglycemia, glucose intolerance, increased insulin and decreased adiponectin in late adulthood. This work aims to characterize adipocyte phenotype and expression profile of genes in the reg...

Intake of fructose-containing sugars is epidemiological and experimentally linked to metabolic syndrome (MS). We recently verified that the dietary polyphenol chrysin was able to abolish some of the metabolic changes induced by fructose-feeding in the rat. Because the role of the intestine upon fructose-induced MS is poorly understood, we decided t...

Cancer is a major cause of death in both developed and developing countries. Polyphenols, abundantly found in plants, possess many anticarcinogenic properties, including inhibition of cancer cell proliferation, tumor growth, angiogenesis, metastasis and inflammation, as well as pro-apoptotic effects. Our study aimed to investigate the effects of a...

Cancer treatment is one of the major fields of interest for the scientific community. Investment in cancer research is costly but essential to provide patients with more effective and safe treatments. In this project, we describe the synthesis and characterization of new thiazole derivatives coupled to CPP2, a cell-penetrating peptide (CPP) reporte...

Metformin has been the first-line drug for the treatment of type II diabetes mellitus for decades, being presently the most widely prescribed antihyperglycemic drug. Retrospective studies associate the use of metformin with a reduction in cancer incidence and cancer-related death. However, despite extensive research about the molecular effects of m...

Wild animals may be considered important reservoirs for bacterial pathogens and, consequently, possible sources of infection for humans. In this study, selected multidrug-resistant bacteria (Acinetobacter spp., Aeromonas salmonicida, Klebsiella pneumoniae, Pseudomonas fluorescens and Shewanella putrefaciens) isolated from wild animals were characte...

Polyphenols are a group of substances present in plant-based foods such as apples and in plant-based beverages such as red wine. This review shows that polyphenols interfere with intestinal sugar transporters, modulating their function and altering glucose and fructose absorption. Inhibition of intestinal glucose and fructose absorption contributes...

The synthesis and crystal structure of two new copper(I) compounds with molecular formula of {Cu4[(µ3-thiocrome)2Cl4]∙2(H2O)}n 1, and Cu2[(µ2-thiocrome)2Cl2] 2 are reported. The crystal structure of compounds 1 and 2 are solved by single crystal X-ray diffraction. The reaction of Cu(II) with thiamine chloride in water at room temperature produces C...

The pathogenesis of various gastrointestinal diseases, including gastrointestinal cancers and inflammatory bowel disease, is associated with increased oxidative stress levels. We aimed to investigate the effect of oxidative stress induced by tert-butylhydroperoxide (TBH) on the uptake of 3H-deoxy-D-glucose (3H-DG) and 14C-fructose by the human inte...

Our aim was to investigate the effect of some xenobiotics on placentation-related processes in an extravillous trophoblastic cell line (HTR-8/SVneo cells). Amphetamine, MDMA, theophylline, and fluoxetine, but not nicotine, cocaine, and caffeine, had a negative effect on cell proliferation rates, culture growth, viability, or migratory capacity. The...

Our aim was to investigate the effect of two xenobiotics to which pregnant woman may be exposed, the drug of abuse ethanol (EtOH) (and its metabolite acetaldehyde (ACA)) and the therapeutic agent metformin (METF), on placentation-related processes in an extravillous trophoblastic (EVTs) cell line (HTR-8/SVneo cells). EtOH, ACA and METF (24 h) signi...

In the last years, metabolic reprogramming became a new key hallmark of tumor cells. One of its components is a deviant energetic metabolism, known as Warburg effect—an aerobic lactatogenesis—characterized by elevated rates of glucose uptake and consumption with high-lactate production even in the presence of oxygen. Because many cancer cells displ...

This work aimed to investigate the effect of metformin on cellular glucose uptake and metabolism by breast cancer cells, as a mechanism contributing to its anticancer properties. Estrogen and progesterone receptor-positive (MCF-7) and triple-negative (MDA-MB-231) breast cancer cell lines were used as in vitro models of breast cancer. Short-term (26...

Preeclampsia is a pregnancy disorder characterized by maternal blood pressure, fetal growth restriction and intrauterine hypoxia. Folic acid is a vitamin required during pregnancy. In this work, we investigated the relationship between preeclampsia and the intake of distinct doses of folic acid during pregnancy. Considering that preeclampsia is ass...

Background Butyrate (BT) is a short-chain fatty acid produced in the intestinal lumen by bacterial fermentation of undigested dietary fibre. Besides being the main energy source for colonic epithelium, BT also stimulates proliferation and differentiation of healthy colonocytes, induces apoptosis of transformed cells and has anti-inflammatory proper...

Long-chain polyunsaturated fatty acids (LC-PUFAs) play a fundamental role during pregnancy for both the health of the pregnant woman and for the growth and development of the fetus, being particularly important for development of the fetal nervous and visual systems. Apart from serving as energy substrates, they are essential components of membrane...

Gestational diabetes is a state of glucose intolerance with onset during pregnancy, which is associated with short and long-term complications to the offspring. Folates, which are critically important to pregnancy, are used to prevent the risk of neural tube defects. Considering that: (a) GDM programs the offspring for metabolic dysfunction later i...

We previously described a negative effect of xanthohumol (XN) upon placentation-related processes. We aimed to better characterize this effect by investigating the effect of XN upon the uptake of arachidonic acid (ARA), a crucial nutrient during pregnancy, by the HTR-8/SVneo human first-trimester extravillous trophoblast cell line and its relations...

Metformin interferes with nutrient uptake by breast cancer cells

Intake of high-fructose products is associated with metabolic syndrome development. We investigated if dietary polyphenols can interfere with fructose absorption by the human intestinal epithelial Caco-2 cell line. Acutely, several polyphenols induced a significant decrease (15–20%) in ¹⁴C-fructose uptake. Chronically, ¹⁴C-fructose uptake was also...

Four new examples of copper complexes [Cu(L1)2(H2O)4] (1), [Cu(HL1)2(H2O)2](NO3)2 (2), [Cu(HL1)Cl]∞ (3), [Cu(HL2)(phen)(H2O)](NO3)·3(H2O) (4) with HL1 = vitamin B3, H2L2 = 2-hydroxy-vitamin B3, phen = 1,10-phenanthroline, were synthesized and their structures solved by single crystal X-ray diffraction. For all complexes, vitamin B3 acts as monodent...

This work aimed to investigate the possible interference of metformin with glucose and methionine uptake by MCF-7 breast cancer cells, as a mechanism contributing to its anticarcinogenic effect.

The investment in cancer research is critical to find more and better treatments, but essentially to save lives. Here, we describe the synthesis and characterization on new bromothiazole derivatives with amino acids and with core of nitazoxamide, an FDA-approved antiprotozoal drug. Using a human adenocarcinoma-derived cell line (the Caco-2 cell lin...

This work aimed to investigate the possible interference of metformin with glucose and methionine uptake by MCF-7 breast cancer cells, as a mechanism contributing to its anticarcinogenic effect.

Objective Colorectal cancer (CRC) is the second leading cause of cancer death in occidental countries. Chronic inflammatory bowel disease (crohn’s disease and ulcerative colitis) is associated with an increased risk for CRC development. The aim of this work was to investigate the relationship between inflammatory status and absorption of nutrients...

Breast cancer is one of the most frequent cancers in the population, especially in older women. Estrogen is known to be a key hormone in the development and progression of mammary carcinogenesis. In this study, we investigated if the procarcinogenic effect of 17β-estradiol (E2) in breast cancer MCF-7 cells is dependent on changes in glucose or foli...

This work aimed to investigate the possible interference of metformin with glucose and methionine uptake by MCF-7 breast cancer cells, as a mechanism contributing to its anticarcinogenic effect.

The cancer drug development process has become increasingly costly and inefficient resulting in few highly effective drugs reaching the market yearly [1]. Cell-Penetrating Peptides (CPP) represent a novel type of cellular delivery agent, and they can be a new and improved technique for delivery over a cell barrier [2]. Fluorescein-tagged octaargini...

Our aim was to investigate the effect of high levels of glucose, insulin, leptin, and tumor necrosis factor alpha, biomarkers of diabetes in pregnancy, in the process of placentation, using as a cell model a first trimester extravillous human trophoblast cell line (HTR8/SVneo cells). Exposure of HTR8/SVneo cells for 24 hours to either glucose (20 m...

Highlights: Fermentation of the dietary fiber by intestinal microflora results in production of butyrate.Butyrate possesses anticarcinogenic effect at the colonic level.Three transporters (MCT1, SMCT1 and BCRP) regulate the intracellular concentration of BT in colonic epithelial cells.Changes in the expression of these transporters occur in colore...

One of the cancer molecular hallmarks is a deviant energetic metabolism, known as the Warburg effect, whereby the rate of glucose uptake is significantly increased and a high rate of glycolysis and lactic acid production occurs even when oxygen is present-"aerobic lactatogenesis". Accordingly, GLUT1 and MCT1, which are the main glucose and lactate...

One of the cancer molecular hallmarks is a deviant energetic metabolism, known as the Warburg effect, whereby the rate of glucose uptake is significantly increased and a high rate of glycolysis and lactic acid production occurs even when oxygen is present. Accordingly, GLUT1 and MCT1, which are the main glucose and lactate membrane transporters in...

In this study, we aimed to investigate modulation of glucose uptake by the HTR-8/SVneo human first-trimester extravillous trophoblast cell line by a series of compounds and to study its consequences upon cell proliferation, viability and migration. We observed that uptake of 3H-deoxy-d-glucose (3H-DG; 10 nM) was time-dependent, saturable, inhibited...

Our group has previously demonstrated that perigestational high folic acid (HFA) exposure predisposes female offspring to an insulin-resistant state and renders them more susceptible to develop metabolic dysfunction in adulthood after a metabolic challenge with fructose feeding (1). This work aims to characterize the liver fatty acid profile in adu...