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- Diabetic neuropathy and oxidative stress: a systematic review focused on oxidative stress biomarkers analysisPublication . Cunha, Sofia; Nascimento, Ana Paula; Vieira, Mónica; Prudêncio, CristinaDiabetic neuropathy is a worldwide disease with great impact in modern society. Diabetes may lead to the overproduction of reactive oxygen species, resulting in an imbalance in body’s redox homeostasis. Oxidative stress is pointed as an important phenomenon associated with several disease states, including diabetic neuropathy.
- Evaluation of the potential of marine cyanobacteria towards Alzheimer’s diseasePublication . Moreira, Ana Rita; Silva, Ana Margarida; Vieira, Mónica; Martins, RosárioAlzheimer’s disease (AD) is one of the most prevalent neurodegenerative diseases (NDs) and the major cause of dementia. Despite the constant efforts to achieve cure, no treatment is currently effective and new approaches are urgently needed. Marine biotechnology has been at the frontline for the bioprospection of natural sources to treat ND. Several marine compounds have already provided evidence for anti-AD drugs by acting in mechanisms such as the inhibition of acetylcholinesterase (AChE). Among marine organisms, cyanobacteria have been recognized as a major source of bioactive compounds and the potential towards AD has been highlighted, namely AChE inhibitors. This project is included in a screening program that aims to evaluate the potential of cyanobacteria from the Culture Collection of CIIMAR -LEGE-CC against AD. In this work, 80 fractions of marine cyanobacteria were screened for the potential to inhibit AChE since this is a proven enzyme target to ameliorate the loss of cholinergic signal and to induce cytotoxicity in the neuroblastoma cell line SHY5Y, in the normal fibroblasts cell line 3T3L1, and in the endothelial cells from central nervous system capillaries hCMEC/D3. Results considering the enzymatic assays and cytotoxic assays revealed that the fractions are not toxic or with low toxicity. The strains Phormidium sp; an unidentified filamentous Synechococcales and Nodosilinea nodulosa revealed moderate toxicity towards AChE.
- New therapeutic approaches based on ionic liquidsPublication . Ferraz, Ricardo; Teixeira, Cátia; Prudêncio, Cristina; Teixeira, Dulce; Vieira, Mónica; Gomes, PaulaIonic liquids (ILs) are currently defined as salts (with at least one organic ion) stable above their melting point. They began to be used mainly as solvents, but quickly drew the attention of the Life Sciences, as some of the characteristics of those compounds may be relevant in therapeutic applications. ILs can show more interesting physicochemical properties at the level of active pharmaceutical ingredients such as water solubility, in addition to the fact that ILs (liquids at room temperature and/or human body temperature) do not present polymorphism, an aspect which often limits the conditions of use and therapeutic efficacy of solid active pharmaceutical ingredients. This line of research seeks, through a careful choice of the ions, to fine-tune some of these properties, and to study the combination of two bioactive molecules that have ionizable groups of opposite charge, forming ionic liquids with a dual therapeutic effect.
- The effect of high concentrations of vitamin C on a H2O2 - oxidative stress induced yeast modelPublication . Costa, Ana Rita; Cunha, Sofia; Nascimento, Ana Paula; Vieira, Mónica; Prudêncio, CristinaNowadays, the ageing of population is conducting to a rise in the number of individuals with age-related illnesses, in which neurodegenerative diseases (ND) are included. Regardless of many variations in etiology and diverse mechanisms of cell injury, most of ND share high levels of oxidative stress, which have been highly referred not only as an underlying factor, but also as a feature. Thus, an actual challenge is to evaluate the role of antioxidants on oxidative stress states and evaluate the magnitude of possible therapeutic effects of these agents. In the present study, the toxic effect of hydrogen peroxide (H2O2) and the antioxidative function of vitamin C were investigated using Saccharomyces cerevisiae as a model. Results were achieved by exposing the yeast model to different concentrations of H2O2 and vitamin C, itself or combined, and colony forming units counting after 48 h incubation at 30ºC in Yeast Extract Peptone Dextrose agar plates. The results demonstrated that H2O2 exposure decreased yeast cells viability in a dose-dependent manner and that, at an optimal concentration, vitamin C was able to revert its effects. These results improved the understanding of the reversal effect of antioxidant treatment and, therefore, may be helpful on providing insights on a natural antioxidant-based therapy for ND.
- From the gut to the brain: Is microbiota a new paradigm in Parkinson’s disease treatment?Publication . Vilela, Cristiana; Araújo, Bruna; Guedes, Carla; Silva, Rita Caridade; Macedo, Joana Martins; Teixeira, Catarina; Gomes, Eduardo; Prudêncio, Cristina; Vieira, Mónica; Teixeira, Fábio G.Parkinson’s disease (PD) is recognized as the second most prevalent primary chronic neurodegenerative disorder of the central nervous system. Clinically, PD is characterized as a movement disorder, exhibiting an incidence and mortality rate that is increasing faster than any other neurological condition. In recent years, there has been a growing interest concerning the role of the gut microbiota in the etiology and pathophysiology of PD. The establishment of a brain–gut microbiota axis is now real, with evidence denoting a bidirectional communication between the brain and the gut microbiota through metabolic, immune, neuronal, and endocrine mechanisms and pathways. Among these, the vagus nerve represents the most direct form of communication between the brain and the gut. Given the potential interactions between bacteria and drugs, it has been observed that the therapies for PD can have an impact on the composition of the microbiota. Therefore, in the scope of the present review, we will discuss the current understanding of gut microbiota on PD and whether this may be a new paradigm for treating this devastating disease.
- Exploring treatment strategies for paroxysmal nocturnal hemoglobinuria: an overview of registered clinical trialsPublication . Peixoto, Vanda; Prudêncio, Cristina; Vieira, MónicaParoxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disease in which blood cells lack anchored proteins that regulate the complement system. The erythrocytes are then destroyed because of uncontrolled complement activity, leading to intravascular hemolysis (IVH) and a high risk of thrombosis outcome. A huge alteration in the treatment of the disease was the development of terminal complement inhibitors, with the achievement of IVH blockade, reduction or abolishment of red blood cell (RBC) transfusions, and thromboembolic events prevention. However, patients treated with these inhibitors can still present extravascular hemolysis (EVH) caused by C3 activation and residual IVH or clinically relevant levels of breakthrough hemolysis (BTH). Proximal complement inhibitors turned out to be the key to the solution of this problem by targeting components of the proximal complement pathway, avoiding intra and extravascular hemolysis. FDA approved eculizumab, ravulizumab (terminal inhibitors), pegcetacoplan, iptacopan, and danicopan (proximal inhibitors) as a treatment for PNH so far. Various clinical trials are underway to find the most effective method to treat patients with PNH. This review aimed to summarize 71 registered clinical trials in the ClinicalTrials.gov database with the various treatment drugs, possible mechanisms, and novel findings related to PNH treatment.
- The negative impact of cosmeticsPublication . Neves, Joana; Prudêncio, Cristina; Vieira, MónicaCosmetics are widely used by infants, children, adults and workers of salon beauty with different purposes. However, they can cause adverse effects due its composition. This review is focused in the potential adverse effects to the human and other organism’s health and to the environment of some of the ingredients used in the formulation of cosmetics. In order to prevent these harmful effects, there are also alternatives to the potential hazardous substances that should be taken in account by consumers and manufactures when choosing a product in order to enhance the quality of life, avoiding health risks.
- Determination of antimicrobial residues in milk samplesPublication . Batista, Larissa; Pais, Patrick; Fernandes, Rúben; Prudêncio, Cristina; Vieira, MónicaIn farming activities, antimicrobials are widely used as a therapeutic measure in the treatment of bacterial infections, disease prophilaxys and as a growth promoter (food additives) (Marshall & Levy, 2011). The presence of antimicrobial residues in milk may represent risks for human health, namely allergic reactions on hypersensitive individuals, or even cause problems indirectly by development of resistant strains of bacteria (Tillotson, Doern, & Blondeau, 2006).
- Tracing the path between mushrooms and Alzheimer’s Disease—a literature reviewPublication . Silva, Ana Margarida; Preto, Marco; Grosso, Clara; Vieira, Mónica; Delerue-Matos, Cristina; Vasconcelos, Vitor; Reis, Mariana; Barros, Lillian; Martins, RosarioAlzheimer’s disease (AD) is well-known among neurodegenerative diseases for the decline of cognitive functions, making overall daily tasks difficult or impossible. The disease prevails as the most common form of dementia and remains without a well-defined etiology. Being considered a disease of multifactorial origin, current targeted treatments have only managed to reduce or control symptoms, and to date, only two drugs are close to being able to halt its progression. For decades, natural compounds produced by living organisms have been at the forefront of research for new therapies. Mushrooms, which are well-known for their nutritional and medicinal properties, have also been studied for their potential use in the treatment of AD. Natural products derived from mushrooms have shown to be beneficial in several AD-related mechanisms, including the inhibition of acetylcholinesterase (AChE) and β-secretase (BACE 1); the prevention of amyloid beta (Aβ) aggregation and neurotoxicity; and the prevention of Tau expression and aggregation, as well as antioxidant and anti-inflammatory potential. Several studies in the literature relate mushrooms to neurodegenerative diseases. However, to the best of our knowledge, there is no publication that summarizes only AD data. In this context, this review aims to link the therapeutic potential of mushrooms to AD by compiling the anti-AD potential of different mushroom extracts or isolated compounds, targeting known AD-related mechanisms.
- Cluster analysis of noncommunicable diseases in PortugalPublication . Nascimento, Ana Paula; Prudêncio, Cristina; Vieira, Mónica; Pimenta, Rui; Bacelar-Nicolau, HelenaThe most common noncommunicable diseases, such as cardiovascular diseases, cancer or respiratory diseases, are a problem in global and national growth. The World Health Organization (WHO) considers it a priority to study the specific causes of these diseases for trend monitoring. The aim is to identify a hierarchy of clusters of Portuguese mortality by noncommunicable diseases using the ascending hierarchical classification methodology. The results identifying three clusters A, A2 and B2 of diseases are proposed for study. It is suggested that the risk factors and / or pathophysiological mechanisms that in a direct or indirect way may enhance the common development of the pathologies found in the clusters studied should be an object of priority study.