RESUMO
The moderate production of reactive oxidative species (ROS) is important because ROS act as second messengers. However, their depletion through the over-activity of the antioxidant system may lead to reductive stress (RS) which is characterized by an increase in reducing equivalents and an elevation of some components of the antioxidant system disturbing redox homeostasis. Hibiscus sabdariffa Linnaeus (HSL) is a plant with antioxidant properties that provides compounds that favor the antioxidant system. However, excess chronic consumption could lead to the over expression of the antioxidant enzymatic system, and this could contribute to decrease ROS. Therefore, the objective of this study was to evaluate the alteration of the vascular reactivity associated to excessive and chronic consumption of HSL infusions at different percentages. 40 male Wistar rats were divided into 4 groups. Group 1 control (drinking tap water), group 2, 3 and 4, drinking water supplemented with 15, 30 and 60 g/L of HSL calyxes respectively. The systolic blood pressure (SBP), vascular reactivity, morphological changes, and different components of the enzymatic antioxidant system were evaluated in the thoracic aorta by spectrophotometry. We also determined glucose-6-phosphate dehydrogenase (G6PD), glutathione-S-transferase (GST), thioredoxin-reductase (TrxR), glutathione peroxidase (GPx) and glutathione reductase (GR) and some markers of the non-enzimatic system such as the NO3-/NO2-ratio, glutathione (GSH), selenium, thiols, lipoperoxidation (LPO), and 3-nitrityrosine (3-NT). Vasoconstriction was increased and vasorelaxation was decreased. These alterations were reversed by O2- and H2O2. There was an increase in the wall thickness and elastic fibers (p = 0.004 and p = 0.02, respectively) and in G6PD, GPX, TrxR (p = 0.02, p = 0.03, and p = 0.01 respectively). LPO, GSH (p = 0.01), and selenium (p = 0.04) were decreased. There was a decrease in thiols (p < 0.001), 3-NT (p = 0.04) and GST (p = 0.0005) in rats that received the infusion at 3 and 6%. The excess antioxidants provided by the HSL infusions at 3% and 6% modified vascular reactivity, increasing the enzymatic antioxidant system, and depleting ROS.
RESUMO
BACKGROUND AND AIM OF THE STUDY: The aim of this retrospective study was to evaluate the inflammatory response in patients with aortic and/or mitral prostheses, and to correlate the level of inflammatory markers with prosthesis functionality. METHODS: A total of 48 patients with biological or mechanical prostheses was included in the study, in which levels of tumor necrosis factor-alpha (TNFα), interleukin (IL)-1, -4, and -6, interferon-gamma (IFNγ), osteopontin (OPN), intercellular adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), endothelin-1 and C-reactive protein were analyzed. Functionality of the prosthesis was evaluated using transthoracic echocardiography at three years after surgery. RESULTS: The mean period from the date of surgery was seven years. High levels of IL-1 were found in patients with mechanical prostheses compared to those with bioprostheses (p = 0.04). Patients with aortic bioprostheses and stenosis had higher levels of OPN and endothelin-1, those with aortic mechanical prostheses with stenosis had increased levels of matrix metalloproteinase (MMP)-9, OPN and ICAM, and those with aortic mechanical leakage had increased levels of MMP-1 and endothelin-1. In mitral bioprostheses with leakage of endothelin-1, ICAM and MMP-9 levels were increased, while in mechanical prostheses with leakage there were increases of ICAM and endothelin-1. Tricuspid bioprostheses with double lesions had increased levels of OPN and endothelin-1. CONCLUSIONS: Valvular dysfunction was similar across the types of prosthesis material. IL-1 was increased in subjects with mechanical prostheses independently of dysfunction, while in biological prostheses there were increases in OPN and endothelin-1, and these were related to valvular dysfunction. Given that in the analysis of durability and functionality there were no significant differences between biological and mechanical prostheses, biological prostheses may represent the first treatment option in patients with low economic resources, the elderly, and even young patients.
