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- 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.
- The influence of adipocyte secretome on selected metabolic fingerprints of breast cancer cell lines representing the four major breast cancer subtypesPublication . Luís, Carla; Guerra-Carvalho, Bárbara; Braga, Patrícia C.; Guedes, Carla; Patrício, Emília; Alves, Marco G.; Fernandes, Ruben; Soares, RaquelMolecular subtype (MS) is one of the most used classifications of breast cancer (BC). Four MSs are widely accepted according to receptor expression of estrogen, progesterone, and HER2. The impact of adipose tissue on BC MS metabolic impairment is still unclear. The present work aims to elucidate the metabolic alterations in breast cancer cell lines representing different MSs subjected to adipocyte associated factors. Preadipocytes isolated from human subcutaneous adipose tissue were differentiated into mature adipocytes. MS representative cell lines were exposed to mature adipocyte secretome. Extracellular medium was collected for metabolomics and RNA was extracted to evaluate enzymatic expression by RT-PCR. Adipocyte secretome exposure resulted in a decrease in the Warburg effect rate and an increase in cholesterol release. HER2+ cell lines (BT-474 and SK-BR-3) exhibited a similar metabolic pattern, in contrast to luminal A (MCF-7) and triple negative (TN) (MDA-MB-231), both presenting identical metabolisms. Anaplerosis was found in luminal A and TN representative cells, whereas cataplerotic reactions were likely to occur in HER2+ cell lines. Our results indicate that adipocyte secretome affects the central metabolism distinctly in each BC MS representative cell line.
- Oxidative stress genes involved in the virulence-dependent susceptibility to antibiotics in Pseudomonas aeruginosaPublication . Coelho, Pedro Barata; Fernandes, Ruben; Silva, Carina; Oliveira, Marco; Veiga, Marlene; Sá, Sara; Vieira, André; Guedes, Carla; Baylina, PilarPseudomonas aeruginosa is a Gram-negative opportunistic pathogen which rarely causes disease in healthy people. P. aeruginosa, in particular strain PAO1 is also a biological model for studying virulence and bacterial social traits, such as quorum sensing, SOS response among other. Antibiotic response is dependent, among several other factors, to the response to environmental stress conditions. The present study aims to understand the role of 10 PAO1 oxidative gene mutants in the response to antibiotic stress in elastase, protease and pyocyanin-dependent virulence factors. PAO1 was stressed to several antibiotics (penicilins, cephalosporins, macrolides, and quinolones), and the virulence proteins were measured by means of spectroscopic methods. Viability was measured by means of Erythrosin B. PAO1 GGT, GLO1, RubA2, GSH A mutants were the most susceptible to the production of virulence-dependent factors.
- New CTX-M group conferring β-Lactam resistance: A compendium of phylogenetic insights from biochemical, molecular, and structural biologyPublication . Mendonça, Jacinta; Guedes, Carla; Silva, Carina; Sá, Sara; Oliveira, Marco; Accioly, Gustavo; Baylina, Pilar; Barata, Pedro; Pereira, Cláudia; Fernandes, RubenThe production of extended-spectrum β-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of dissemination in different epidemiological contexts. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants distributed in several sublineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular, and structural point of view through homology in amino acid sequences. Our data, combined with described literature, provide phylogenetic and structural evidence of a new group. Thus, herein, we propose six groups among CTX-M enzymes: the already stablished CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, and CTX-M-25 clusters, as well as CTX-M-151 as the new cluster.
- Phylogenetic Insights of β-lactam resistance of the CTX-M familyPublication . Coelho, Pedro Barata; Mendonça, Jacinta; Silva, Carina; Baylina, Pilar; Fernandes, Ruben; Guedes, CarlaBacterial resistance is a major public health concern, particularly against β-lactam antibiotics, one of the most widely used antibacterial drugs. The production of extended-spectrum β-lactamases (ESBLs) is the main defense mechanism found in Gram negative bacteria. Among all the ESBLs, the CTX-M enzymes appear as the most efficient in terms of diffusion in different epidemiological contexts, outnumbering the others. Originated in chromosomal genes of Klyvera spp., the blaCTX-M genes have become associated with mobile genetic elements, such as plasmids, that have mediated inter-replication and dissemination. CTX-M enzymes exhibit a striking plasticity, with a large number of allelic variants belonging to several sub-lineages, which can be associated with functional heterogeneity of clinical relevance. This observational analytical study provides an update of this family, currently with more than 200 variants described, from a phylogenetic, molecular and structural point of view through homology in amino acid sequences. There are currently 6 defined clusters (CTX-M-1, CTX-M-2, CTX-M-8, CTX-M-9, CTX-M-25 and CTX-M-151), with the domains CTX -M-1 and CTX-M-9 presenting subgroups, composed mainly of variants identified as hybrids between them (particularly between CTX-M-14 and CTX-M-15).
- Beyond the brain: The hidden role of cardiorenal dysfunction in Parkinson’s diseasePublication . Teixeira, C.; Araújo, B.; Caridade-Silva, Rita; Martins-Macedo, J.; Guedes,Carla; Gomes, Eduardo; Falcão-Pires, I.; Alencastre, I.; Teixeira, F.; Guedes, Carla; Gomes, EduardoParkinson’s disease (PD) is the second most common neurodegenerative disorder, marked by the progressive loss of dopaminergic neurons in critical areas of the brain, particularly the striatum and substantia nigra. PD's complex nature suggests its interactions with various systemic health issues, particularly those affecting organs outside the central nervous system (CNS), which may increase the risk of developing PD and affect treatment outcomes. Research indicates that individuals with cardiovascular disease (CVD) and chronic kidney disease (CKD) face significantly higher risks of PD, even when controlling for shared risk factors. Notably, alpha-synuclein aggregations, a hallmark of PD, have also been found in the renal and cardiac tissues of patients with PD, CKD, and CVD, highlighting the interconnectedness of these systems. The Zucker fatty and spontaneously hypertensive (ZSF1) rats model metabolic syndrome, which includes kidney issues and heart failure. This study aimed to explore how the ZSF1 phenotype impacts the integrity of dopaminergic neurons and neuroinflammatory processes. Brain tissues from ZSF1 rats were analyzed through immunostaining with markers specific to dopaminergic and glial cells. The results showed a significant decrease in dopaminergic markers in the striatum and substantia nigra, indicating a potential link between cardiorenal dysfunction and neurodegenerative pathways. These findings suggest that systemic health conditions can directly influence PD pathology, emphasizing the complex interactions between the brain, heart, and kidneys, and presenting new opportunities for targeted PD therapies.
- The synergy of dopaminergic system and adult hippocampal neurogenesis in a pre-clinical model of Parkinson’s disease pp85Publication . Araújo, B.; Caridade-Silva, Rita; Vilaça-Ferreira, A.; Martins-Macedo, J.; Teixeira, C.; Soares-Guedes, C.; Svenningsson, P.; Pinto, L.; Teixeira, F.; Guedes, CarlaDepressive disturbances are prevalent in 40% to 50% of clinical cases of Parkinson’s Disease (PD), alongside a common reduction in adult hippocampal neurogenesis observed in both PD and its related conditions. This neurogenesis deficit may affect the clinical course of the disease. With this in mind, we set an experiment using the glial fibrillary acidic protein-thymidine kinase (GFAP-TK) transgenic rat model to assess the impact of impaired adult cytogenesis induced by the antiviral Ganciclovir on PD. The experiment involved a combination of the GFAP-TK model and a 6-hydroxydopamine (6-OHDA) model of PD, while behavioral analyses focused on anxiety, depression, and motor skills. From the results, histological examinations revealed decreased proliferative cells and reduced dopaminergic innervation. Additionally, analysis of newborn and immature neurons occurred in the hippocampus, subventricular zone, and olfactory bulbs, while dopaminergic loss was assessed in regions like the substantia nigra and striatum. Findings indicated that the model exhibited anxiety/depressive-like behaviors and motor impairments, linked to the notable loss of dopaminergic neurons, which appeared to correlate with reduced doublecortin-positive cells in the hippocampus. Moreover, results suggested subtle differences between ipsilateral and contralateral sides, highlighting the dopaminergic system's role in hippocampal adaptation. Therefore, these findings suggest a connection between reduced neurogenesis and dopaminergic neuron loss, hinting that these phenomena might be interrelated. Therefore, investigating this potential regional interconnection may augment our understanding of non-motor dimensions in PD pathophysiology related to motor functions, thereby facilitating the development of enhanced therapeutic strategies for individuals in the early stages of PD.