RESUMO
Cardiovascular diseases are the most common cause of mortality worldwide. Oxidative stress and inflammation are pathophysiological processes involved in the development of cardiovascular diseases; thus, antiinflammatory and antioxidant agents that modulate redox balance have become research targets so as to evaluate their molecular mechanisms of action and therapeutic properties. Astaxanthin, a carotenoid of the xanthophyll group, has potent antioxidant properties due to its molecular structure and its arrangement in the plasma membrane, factors that favor the neutralization of reactive oxygen and nitrogen species. This carotenoid also has prominent antiinflammatory activity, possibly interrelated with its antioxidant effect, and is also involved in the modulation of lipid and glucose metabolism. Considering the potential beneficial effects of astaxanthin on cardiovascular health evidenced by preclinical and clinical studies, the aim of the present review was to describe the molecular and cellular mechanisms associated with the antioxidant and antiinflammatory properties of this carotenoid in cardiovascular diseases, particularly atherosclerosis. The beneficial properties and safety profile of astaxanthin indicate that this compound may be used for preventing progression or as an adjuvant in the treatment of cardiovascular diseases.
Assuntos
Antioxidantes/uso terapêutico , Doenças Cardiovasculares , Glucose/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/prevenção & controle , Humanos , Xantofilas/uso terapêuticoRESUMO
Some nutrients play key roles in maintaining the integrity and function of the immune system, presenting synergistic actions in steps determinant for the immune response. Among these elements, zinc and vitamins C and D stand out for having immunomodulatory functions and for playing roles in preserving physical tissue barriers. Considering the COVID-19 pandemic, nutrients that can optimize the immune system to prevent or lower the risk of severe progression and prognosis of this viral infection become relevant. Thus, the present review aims to provide a comprehensive overview of the roles of zinc and vitamins C and D in the immune response to viral infections, focusing on the synergistic action of these nutrients in the maintenance of physical tissue barriers, such as the skin and mucous membranes. The evidence found in the literature shows that deficiency of one or more of these three elements compromises the immune response, making an individual more vulnerable to viral infections and to a worse disease prognosis. Thus, during the COVID-19 pandemic, the adequate intake of zinc and vitamins C and D may represent a promising pharmacological tool due to the high demand for these nutrients in the case of contact with the virus and onset of the inflammatory process. Ongoing clinical trials will help to clarify the role of these nutrients for COVID-19 management.
RESUMO
Most human tissues used in research are of post mortem origin. This is the case for all brain samples, and due to the difficulty in obtaining a good number of samples, especially in the case of neurodegenerative diseases, male and female samples are often included in the same experimental group. However, the effects of post mortem interval (PMI) and gender differences in the endpoints being analyzed are not always fully understood, as is the case for DNA repair activities. To investigate these effects, in a controlled genetic background, base excision repair (BER) activities were measured in protein extracts obtained from Wistar rat brains from different genders and defined PMI up to 24 hours, using a novel fluorescent-based in vitro incision assay. Uracil and AP-site incision activity in nuclear and mitochondrial extracts were similar in all groups included in this study. Our results show that gender and PMI up to 24 hours have no influence in the activities of the BER proteins UDG and APE1 in rat brains. These findings demonstrate that these variables do not interfere on the BER activities included in these study, and provide a security window to work with UDG and APE1 proteins in samples of post mortem origin.
Assuntos
Encéfalo/metabolismo , Reparo do DNA , Mudanças Depois da Morte , Caracteres Sexuais , Animais , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Feminino , Humanos , Masculino , Ratos , Fatores de TempoRESUMO
The tick Rhipicephalus sanguineus is currently considered an urban plague. For this reason many studies are intended to find methods to control these ectoparasites. Thus, the present study analyzed the ultrastructural modifications of the salivary glands cells of semi-engorged females of R. sanguineus resulting from their exposition to Fipronil (active ingredient of Frontline®). The studied individuals were divided into four groups. Group 1 was exposed to distilled water (control) and groups 2, 3 and 4 were exposed to 1, 5 and 10 ppm of Fipronil, respectively. The salivary gland of ticks subjected to the acaricide showed accelerated process of cell death by atypical apoptosis, as well as augmented cell damages as the concentration of the chemical compound was increased. The acaricide toxicity at cellular level was demonstrated by remarkable changes of elements of the cytoskeleton and spherocrystals (extremely hard inorganic structures). However, tick defense mechanisms, such as the observed autofagic vacuoles proved the cells attempt to preserve their integrity and minimize the devastating action of this chemical compound on the salivary glands.