RESUMEN
Consensus was reached on seven core concepts of physiology using the Delphi method, including "integration," outlined by the descriptor "cells, tissues, organs, and organ systems interact to create and sustain life." This core concept was unpacked by a team of 3 Australian physiology educators into hierarchical levels, identifying 5 themes and 10 subthemes, up to 1 level deep. The unpacked core concept was then circulated among 23 experienced physiology educators for comments and to rate both level of importance and level of difficulty for each theme and subtheme. Data were analyzed using a one-way ANOVA to compare between and within themes. The main theme (theme 1: the body is organized within a hierarchy of structures, from atoms to molecules, cells, tissues, organs, and organ systems) was almost universally rated as Essential. Interestingly, the main theme was also rated between Slightly Difficult to Not Difficult, which was significantly different from all other subthemes. There were two separate subsets of themes in relation to importance, with three themes rating between Essential and Important and the two other themes rating as Important. Two subsets in the difficulty of the main themes were also identified. While many core concepts can be taught concurrently, Integration requires the application of prior knowledge, with the expectation that learners should be able to apply concepts from "cell-cell communication," "homeostasis," and "structure and function," before understanding the overall Integration core concept. As such, themes from the Integration core concept should be taught within the endmost semesters of a Physiology program.NEW & NOTEWORTHY This article proposes the inclusion of a core concept regarding "integration" into physiology-based curricula, with the descriptor "cells, tissues, organs, and organ systems interact to create and sustain life." This concept expands prior knowledge and applies physiological understanding to real-world scenarios and introduces contexts such as medications, diseases, and aging to the student learning experience. To comprehend the topics within the Integration core concept, students will need to apply learned material from earlier semesters.
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Curriculum , Fisiología , Humanos , Australia , Aprendizaje , Fisiología/educaciónRESUMEN
Australia-wide consensus was reached on seven core concepts of physiology. The "movement of substances" core concept with the descriptor "the movement of substances (ions or molecules) is a fundamental process that occurs at all levels of organization in the organism" was unpacked by a team of three Australian physiology educators from the Delphi Task Force into hierarchical levels. There were 10 themes and 23 subthemes arranged in a hierarchy, some 3 levels deep. Using a 5-point Likert scale, the unpacked core concept was then rated for level of importance for students to understand (ranging from 1 = Essential to 5 = Not Important) and level of difficulty for students (ranging from 1 = Very Difficult to 5 = Not Difficult) by the 23 physiology educators from different Australian universities, all with a broad range of teaching and curriculum experience. Survey data were analyzed using a one-way ANOVA to compare between and within concept themes. The main themes all were rated on average as important. There was a wide range of difficulty ratings and more variation for this concept compared with the other core concepts. This may in part be due to the physical forces such as gravity, electrochemistry, resistance, and thermodynamics that underpin this concept, which in themselves are inherently complex. Separation of concepts into subthemes can help prioritize learning activities and time spent on difficult concepts. Embedding of core concepts across curricula will allow commonality and consistency between programs of study and inform learning outcomes, assessment, and teaching and learning activities.NEW & NOTEWORTHY This article unpacks the core concept of the "movement of substances" within the body, with the aim to produce a resource that will help guide the teaching of physiology at tertiary education institutes in Australia. The concept introduces fundamental knowledge of the factors that drive substance movement and then applies them in physiological contexts.
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Aprendizaje , Fisiología , Humanos , Australia , Curriculum , Estudiantes , Escolaridad , Fisiología/educaciónRESUMEN
A task force of physiology educators from 25 Australian universities generated an Australia-wide consensus on seven core concepts for physiology curricula. One adopted core concept was "cell membrane," defined as "Cell membranes determine what substances enter or leave the cell and its organelles. They are essential for cell signaling, transport, and other cellular functions." This concept was unpacked by a team of 3 Australian physiology educators into 4 themes and 33 subthemes arranged in a hierarchical structure up to 5 levels deep. The four themes related to defining the cell membrane, cell membrane structure, transport across cell membranes, and cell membrane potentials. Subsequently, 22 physiology educators with a broad range of teaching experience reviewed and assessed the 37 themes and subthemes for importance for students to understand and the level of difficulty for students on a 5-point Likert scale. The majority (28) of items evaluated were rated as either Essential or Important. Theme 2: cell membrane structure was rated as less important than the other three themes. Theme 4: membrane potential was rated most difficult, while theme 1: defining cell membranes was rated as the easiest. The importance of cell membranes as a key aspect of biomedical education received strong support from Australian educators. The unpacking of the themes and subthemes within the cell membrane core concept provides guidance in the development of curricula and should facilitate better identification of the more challenging aspects within this core concept and help inform the time and resources required to support student learning.NEW & NOTEWORTHY The "cell membrane" core concept was unpacked by a team of Australian physiology educators into a conceptual framework to provide guidance for students and educators. Key themes in the cell membrane core concept were cell membrane definition and structure, transport across cell membranes, and membrane potentials. Australian educators reviewing the framework identified cell membrane as an essential yet relatively simple core concept, suggesting that this is well-placed in foundational physiology courses across a diverse range of degrees.
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Curriculum , Fisiología , Humanos , Australia , Membrana Celular , Estudiantes , Universidades , Fisiología/educaciónRESUMEN
A national Task Force of 25 Australian physiology educators used the Delphi protocol to develop seven physiology core concepts that were agreed to nationally. The aim of the current study was to unpack the "physiological adaptation" core concept with the descriptor "organisms adjust and adapt to acute and chronic changes in the internal and external environments across the lifespan." This core concept was unpacked by three Task Force members and a facilitator into four themes and nine subthemes that encompass the role of stressors and disturbed homeostasis in adaptation and the capacity for, and the nature of, the physiological adaptation. Twenty-two Task Force members then provided feedback and rated the themes and subthemes for level of importance and difficulty for students to learn via an online survey using a five-point Likert scale. Seventeen respondents completed all survey questions. For all themes/subthemes, importance was typically rated 1 (Essential) or 2 (Important) (n = 17, means ±SD ranged from 1.1 ± 0.3 to 2.2 ± 0.9), and difficulty was typically rated 3 (Moderately Difficult) (n = 17, means ranged from 2.9 ± 0.7 to 3.4 ± 0.9). Subtle differences in the proportion of importance scores (n = 17, Fisher's exact: P = 0.004, ANOVA: F12,220 = 2.630, P = 0.003; n = 22, Fisher's exact: P = 0.002, ANOVA: F12,281 = 2.743, P < 0.001), but not difficulty scores, were observed between themes/subthemes, and free-text feedback was minor. The results suggest successful unpacking of the physiological adaptation core concept. The themes and subthemes can inform the design of learning outcomes, assessment, and teaching and learning activities that have commonality and consistency across curricula.NEW & NOTEWORTHY An Australian Task Force of physiology educators identified physiological adaptation as a core concept of physiology. It was subsequently unpacked into four themes and nine subthemes. These were rated, by the Task Force, Essential or Important and Moderately Difficult for students to learn. The themes and subthemes can inform the design of learning outcomes, assessments, and teaching and learning activities that have commonality and consistency across curricula.
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Aprendizaje , Fisiología , Humanos , Australia , Curriculum , Estudiantes , Adaptación Fisiológica , Fisiología/educaciónRESUMEN
Core concepts in physiology, designed by physiology educators to promote improved learning and teaching, have existed for over a decade. This study aimed to investigate the extent to which a set of 15 core concepts of physiology (developed by Michael and McFarland, U.S.-based educators) are reflected in the learning outcomes (LOs) of units (subjects) comprising physiology curricula in Australian universities. From publicly accessible online information, we identified 17 Australian universities that offered a physiology major for undergraduate degree students and downloaded 788 LOs from the 166 units that comprised the majors. Each LO was blindly mapped against the 15 core concepts by 8 physiology educators from 3 Australian universities. Additionally, text-matching software was employed to match keywords and phrases (identified as descriptors of the 15 core concepts) against the LOs. The frequency of individual words and two-word phrases for each core concept was calculated and ranked. There was variability in rating LOs for the same university among academic mappers; nevertheless, many of the 15 core concepts did not appear to be adequately covered in the LOs. Two core concepts most matched manually were in the top three most mapped by the software. These were, from most common, structure/function and interdependence. Our findings suggest a lack of alignment of LOs with the core concepts across Australian physiology curricula. This highlights the need for Australia-wide agreement on a set of core concepts in physiology as the first step in collaboratively improving assessment and learning and teaching practice in physiology.NEW & NOTEWORTHY This is the first time an existing set of core concepts for physiology, developed by Michael and McFarland (U.S.-based educators), have been mapped against unit (subject) learning outcomes across physiology curricula in Australian universities to gauge uptake and the need for agreement on a set of core concepts in the Australian higher education context.
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Curriculum , Fisiología , Humanos , Australia , Fisiología/educación , Estudiantes , UniversidadesRESUMEN
Australia-wide consensus was reached on seven core concepts of physiology, which included homeostasis, a fundamental concept for students to understand as they develop their basic knowledge of physiological regulatory mechanisms. The term homeostasis is most commonly used to describe how the internal environment of mammalian systems maintains relative constancy. The descriptor "the internal environment of the organism is actively regulated by the responses of cells, tissues, and organs through feedback systems" was unpacked by a team of three Australian Physiology educators into 5 themes and 18 subthemes arranged in a hierarchy. Using a five-point Likert scale, the unpacked concept was rated by 24 physiology educators from 24 Australian Universities for level of importance and level of difficulty for students. Survey data were analyzed using a one-way ANOVA to compare between and within concept themes and subthemes. There were no differences in main themes for level of importance, with all ratings between essential or important. Theme 1: the organism has regulatory mechanisms to maintain a relatively stable internal environment, a process known as homeostasis was almost unanimously rated as essential. Difficulty ratings for unpacked concept themes averaged between slightly difficult and moderately difficult. The Australian team concurred with published literature that there are inconsistencies in the way the critical components of homeostatic systems are represented and interpreted. We aimed to simplify the components of the concept so that undergraduates would be able to easily identify the language used and build on their knowledge.NEW & NOTEWORTHY The homeostasis core concept of physiology was defined and unpacked by an Australian team with the goal of constructing a resource that will improve learning and teaching of this core physiology concept in an Australian Higher Education context.
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Aprendizaje , Fisiología , Animales , Australia , Homeostasis/fisiología , Mamíferos , Fisiología/educación , UniversidadesRESUMEN
An Australia-wide consensus was reached on seven core concepts of physiology, one of which was "structure and function" with the descriptor "Structure and function are intrinsically related to all levels of the organism. In all physiological systems, the structure from a microscopic level to an organ level dictates its function." As a framework for the structure and function core concept, the renal system was unpacked by a team of 5 Australian Physiology educators from different universities with extensive teaching experience into hierarchical levels, with 5 themes and 25 subthemes up to 3 levels deep. Within theme 1, the structures that comprise the renal system were unpacked. Within theme 2, the physiological processes within the nephron such as filtration, reabsorption, and secretion were unpacked. Within theme 3, the processes involved in micturition were unpacked. In theme 4, the structures and processes involved in regulating renal blood flow and glomerular filtration were unpacked; and within theme 5, the role of the kidney in red blood cell production was unpacked. Twenty-one academics rated the difficulty and importance of each theme/subtheme, and results were analyzed using a one-way ANOVA. All identified themes were validated as "essential" to "important"/"moderately important" and rated between "difficult" to "not difficult." A similar framework consisting of structure, physiological processes, physical processes, and regulation can be used to unpack other body systems. Unpacking of the body systems will provide a list of what students should be taught in curricula across Australian universities and inform assessment and learning activities.NEW & NOTEWORTHY This is the first attempt to unpack and validate the "structure and function" core concept in physiology with all Australian educators. We unpacked the renal system into themes with hierarchical levels, which were validated by an experienced team of Australian physiology educators. Our unpacking of the "structure and function" core concept provides a specific framework for educators to apply this important concept in physiology education.
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Curriculum , Riñón , Fisiología , Humanos , Australia , Riñón/fisiología , Aprendizaje , Fisiología/educación , UniversidadesRESUMEN
An Australia-wide consensus was reached on seven core concepts of physiology, one of which was cell-cell communication. Three physiology educators from a "core concepts" Delphi task force "unpacked" this core concept into seven different themes and 60 subthemes. Cell-cell communication, previously unpacked and validated, was modified for an Australian audience to include emerging knowledge and adapted to increase student accessibility. The unpacked hierarchical framework for this core concept was rated by 24 physiology educators from separate Australian universities, using a five-point scale for level of importance for student understanding (ranging from 1 = Essential to 5 = Not Important) and level of difficulty (ranging from 1 = Very Difficult to 5 = Not Difficult). Data were analyzed with the Kruskal-Wallis test with Dunn's multiple comparison test. The seven themes were rated within a narrow range of importance (1.13-2.4), with ratings of Essential or Important, and statistically significant differences between the themes (P < 0.0001, n = 7). The variance for the difficulty rating was higher than for importance, ranging from 2.15 (Difficult) to 3.45 (between Moderately Difficult and Slightly Difficult). Qualitatively, it was suggested that some subthemes were similar and that these could be grouped. However, all themes and subthemes were ranked as Important, validating this framework. Once finalized and adopted across Australian universities, the unpacked core concept for cell-cell communication will enable the generation of tools and resources for physiology educators and improvements in consistency across curricula.NEW & NOTEWORTHY Seven core concepts, including cell-cell communication, were identified by an Australian Delphi task force of physiology educators. The previously "unpacked" concept was adapted for Australian educators and students to develop a framework with seven themes and 60 subthemes. The framework was successfully validated by the original Delphi panel of educators and will provide a valuable resource for teaching and learning in Australian universities.
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Comunicación Celular , Curriculum , Fisiología , Humanos , Australia , Aprendizaje , Fisiología/educaciónRESUMEN
A set of core concepts ("big ideas") integral to the discipline of physiology are important for students to understand and demonstrate their capacity to apply. We found poor alignment of learning outcomes in programs with physiology majors (or equivalent) from 17 Australian universities and the 15 core concepts developed by a team in the United States. The objective of this project was to reach Australia-wide consensus on a set of core concepts for physiology, which can be embedded in curricula across Australian universities. A four-phase Delphi method was employed, starting with the assembling of a Task Force of physiology educators with extensive teaching and curriculum development expertise from 25 Australian universities. After two online meetings and a survey, the Task Force reached agreement on seven core concepts of physiology and their descriptors, which were then sent out to the physiology educator community across Australia for agreement. The seven core concepts and their associated descriptions were endorsed through this process (n = 138). In addition, embedding the core concepts across the curriculum was supported by both Task Force members (85.7%) and educators (82.1%). The seven adopted core concepts of human physiology were Cell Membrane, Cell-Cell Communication, Movement of Substances, Structure and Function, Homeostasis, Integration, and Physiological Adaptation. The core concepts were subsequently unpacked into themes and subthemes. If adopted, these core concepts will result in consistency across curricula in undergraduate physiology programs and allow for future benchmarking.NEW & NOTEWORTHY This is the first time Australia-wide agreement has been reached on the core concepts of physiology with the Delphi method. Embedding of the core concepts will result in consistency in physiology curricula, improvements to teaching and learning, and benchmarking across Australian universities.
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Curriculum , Fisiología , Humanos , Australia , Consenso , Técnica Delphi , Universidades , Fisiología/educaciónRESUMEN
A limited number of studies have explored the impact of blended exercise physiology theory curricula on student learning and experience. This study aimed to investigate the impact of an exercise physiology blended learning theory module on student performance, engagement, and perceptions. The module, which comprised a range of elements (student guide, lecturer-recorded videos, supplementary videos, formative quizzes, workshops, and discussion forum), was implemented in a third-year subject taken by students in nonspecialist undergraduate science, technology, engineering, and mathematics (STEM) degrees. Students chose which elements to engage with to support their learning. Exam performance was assessed by comparing exam marks from fully face-to-face delivery to the blended delivery with an independent t test. Student perceptions were determined via an end-of-module questionnaire comprised of Likert-scale questions and open-ended questions. Descriptive statistical analysis was conducted on the Likert-scale responses, and qualitative content analysis was conducted on the open-ended responses. Student engagement with online resources was determined through analysis of access statistics from the learning management system. Student exam marks in the blended learning student group were significantly higher (P < 0.0001) than in the face-to-face group, even though the questions were of a higher Bloom's level in the blended learning group. Students preferred blended delivery over fully face-to-face delivery. Most students accessed the student guide, lecturer-recorded videos, and quizzes, with supplementary videos, workshops, and discussion forums accessed by fewer students. In conclusion, a blended exercise physiology theory module improved student exam performance and was positively perceived by students, and engagement with the elements of the module was varied.NEW & NOTEWORTHY Few studies have explored the impact of blended delivery of exercise physiology theory curricula on student learning and experience. This study investigated the impact of a novel blended model on student learning and experience. The module comprised a range of elements (student guide, lecturer-recorded videos, supplementary videos, formative quizzes, workshops, and discussion forum), where students were able to choose which elements to engage with to support their learning.
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Rendimiento Académico , Curriculum , Humanos , Aprendizaje , EstudiantesRESUMEN
Expert educators in science argue that science graduates are often lacking skills in effectively communicating scientific information to lay audiences. To address this, we designed a project, Communicating Disease, for final-year undergraduate human pathophysiology students. Students chose a disease, a relevant nonscientific target audience, and a mode of communication and produced a communiqué designed to educate the audience on the pathophysiology of the disease. Separately, students justified their choice of disease and target audience. Upon completion of the project, students completed an anonymous questionnaire, and their submitted work was analyzed. Our study demonstrated that students thought it was important to learn how to effectively communicate science to a lay audience and felt that the project had supported them in developing knowledge and skills that enabled them to do so. Students were adequately challenged, and most students gave their best effort to the project, indicating a high level of engagement. Evaluation of student performance was consistent with the students' own perceptions and showed that most students communicated the pathophysiology effectively to the target audience and appropriately justified their choice of disease and target audience. Nevertheless, opportunities for improvement with some aspects of communication, production quality, and creativity were evident. This model is suitable for a range of scientific disciplines to engage students in developing their ability to communicate scientific information to lay audiences-a skill that it can be argued is vital for improving the scientific literacy of our community at large.
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Aprendizaje , Estudiantes , Comunicación , HumanosRESUMEN
The consequences of oxidative stress and inflammation are implicated in a wide range of diseases, including rheumatoid arthritis and Parkinson's disease. The status of antioxidant capacity in rheumatoid arthritis and Parkinson's disease remains unclear, in part due to common practice of assaying erythrocytes separately to plasma. This method removes any synergistic interactions between plasma and erythrocyte-based antioxidants. The experiments in this report tested antioxidant capacity in whole blood, erythrocytes and plasma by group and disease stage. Medically diagnosed patients were recruited along with appropriate control group participants. Fasting venous blood was assayed using chemiluminescence methods for: time to maximum light emitted, maximum light emitted, and plasma antioxidant capacity in vitamin E analogue units. Here we demonstrate that whole blood exhibits higher antioxidant capacity than either plasma or erythrocytes assayed separately. We report increased oxidative stress in the blood of rheumatoid arthritis patients by group (p = 0.018, p = 0.049). We show increased antioxidant capacity in Parkinson's disease patients by group (p < 0.001). For later stage Parkinson's disease patients, we report reduced oxidative stress (p = 0.025), and increased antioxidant capacity and for erythrocytes (p < 0.001, p = 0.004) and whole blood (p < 0.001, p = 0.003). Early stage Parkinson's disease showed higher antioxidant capacity on only one measure (p = 0.008). Whole blood chemiluminescence is a useful technique for determining redox status in disease and might help clarify the role of oxidative stress in rheumatoid arthritis and Parkinson's disease.
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Antioxidantes/análisis , Artritis Reumatoide/sangre , Luminiscencia , Enfermedad de Parkinson/sangre , Anciano , Artritis Reumatoide/diagnóstico , Eritrocitos/química , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/diagnósticoRESUMEN
Many conventional science courses contain subjects embedded with laboratory-based activities. However, research on the benefits of positioning the practicals within the theory subject or developing them distinctly from the theory is largely absent. This report compared results in a physiology theory subject among three different cohorts of students: those taking the theory subject alone, those taking it concurrent with a physiology practicum subject, and those who previously took the subject when it had practicums embedded within the one subject. The path model shows that students taking both physiology theory and physiology practicum attained a significantly higher result in online tests compared with those who took the theory subject alone (P < 0.05) and that this translated to a significantly higher result in the end-of-semester examination. Similarly, students taking both physiology theory and the physiology practicum attained a significantly higher end-examination result compared with those who took the physiology subject in previous years when the practicums were embedded within the theory subject (P < 0.05). In both cases, this increase was largely attained in components that tested critical thinking and deep learning (short theory application questions and extended written questions). We conclude that students undertaking both physiology theory and the physiology practicum likely performed better in the theory subject due to better problem-solving skills and a more developed understanding of theoretical content. We suggest that consideration be given in all science curricula to the separation of theory and practicum by developing two subjects with clearly defined different learning outcomes.
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Aprendizaje , Fisiología/educación , Enseñanza/métodos , Comprensión , Curriculum , Evaluación Educacional , Humanos , Modelos Educacionales , Aprendizaje Basado en ProblemasRESUMEN
BACKGROUND: This study aimed to determine if 25 days of canola oil intake in the absence of excess dietary salt or together with salt loading affects antioxidant and oxidative stress markers in the circulation. A further aim was to determine the mRNA expression of NADPH oxidase subunits and superoxide dismutase (SOD) isoforms in the aorta of stroke-prone spontaneously hypertensive (SHRSP) rats. METHODS: Male SHRSP rats, were fed a defatted control diet containing 10% wt/wt soybean oil or a defatted treatment diet containing 10% wt/wt canola oil, and given tap water or water containing 1% NaCl. Blood was collected at the end of study for analysis of red blood cell (RBC) antioxidant enzymes, RBC and plasma malondialdehyde (MDA), plasma 8-isoprostane and plasma lipids. The aorta was removed and the mRNA expression of NOX2, p22phox, CuZn-SOD, Mn-SOD and EC-SOD were determined. RESULTS: In the absence of salt, canola oil reduced RBC SOD and glutathione peroxidase, and increased total cholesterol and LDL cholesterol compared with soybean oil. RBC glutathione peroxidase activity was significantly lower in both the salt loaded groups compared to the soybean oil only group. In addition, RBC MDA and plasma HDL cholesterol were significantly higher in both the salt loaded groups compared to the no salt groups. Plasma MDA concentration was higher and LDL cholesterol concentration lower in the canola oil group loaded with salt compared to the canola oil group without salt. The mRNA expression of NADPH oxidase subunits and SOD isoforms were significantly reduced in the canola oil group with salt compared to canola oil group without salt. CONCLUSION: In conclusion, these results indicate that canola oil reduces antioxidant status and increases plasma lipids, which are risk factors for cardiovascular disease. However, canola oil in combination with salt intake increased MDA, a marker of lipid peroxidation and decreased NAPDH oxidase subunits and aortic SOD gene expression.
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Aorta/metabolismo , Ácidos Grasos Monoinsaturados/efectos adversos , Hipertensión/dietoterapia , Hipertensión/fisiopatología , Estrés Oxidativo , Accidente Cerebrovascular/etiología , Animales , Aorta/enzimología , Biomarcadores/sangre , Dieta Hiposódica , Dinoprost/análogos & derivados , Dinoprost/sangre , Eritrocitos/enzimología , Eritrocitos/metabolismo , Ácidos Grasos Monoinsaturados/uso terapéutico , Regulación Enzimológica de la Expresión Génica , Hipercolesterolemia/etiología , Hipercolesterolemia/prevención & control , Hipertensión/sangre , Isoenzimas/sangre , Isoenzimas/genética , Isoenzimas/metabolismo , Peroxidación de Lípido , Masculino , Oxidorreductasas/sangre , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , ARN Mensajero/metabolismo , Distribución Aleatoria , Aceite de Brassica napus , Ratas , Ratas Endogámicas SHR , Factores de Riesgo , Accidente Cerebrovascular/prevención & controlRESUMEN
BACKGROUND: Canola oil shortens the life span of stroke-prone spontaneously hypertensive (SHRSP) rats compared with rats fed soybean oil when given as the sole dietary lipid source. One possible mechanism leading to the damage and deterioration of organs due to canola oil ingestion is oxidative stress. This study investigated the effect of canola oil intake on oxidative stress in this animal model. METHOD: Male SHRSP rats, were fed a defatted control diet containing 10% wt/wt soybean oil or a defatted treatment diet containing 10% wt/wt canola oil, and given water containing 1% NaCl. Blood pressure was measured weekly. Blood was collected prior to beginning the diets and at the end of completion of the study for analysis of red blood cell (RBC) antioxidant enzymes, RBC and plasma malondialdehyde (MDA), plasma 8-isoprostane and plasma lipids. RESULTS: Canola oil ingestion significantly decreased the life span of SHRSP rats compared with soybean oil, 85.8 ± 1.1 and 98.3 ± 3.4 days, respectively. Systolic blood pressure increased over time with a significant difference between the diets at the 6th week of feeding. Canola oil ingestion significantly reduced RBC superoxide dismutase, glutathione peroxidase and catalase activities, total cholesterol and low-density lipoprotein cholesterol compared with soybean oil. There were no significant differences in RBC MDA concentration between canola oil fed and soybean oil fed rats. In contrast, plasma MDA and 8-isoprostane concentration was significantly lower in the canola oil group compared to the soybean oil group. CONCLUSION: In conclusion, canola oil ingestion shortens the life span of SHRSP rats and leads to changes in oxidative status, despite an improvement in the plasma lipids.
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Grasas de la Dieta/farmacología , Ácidos Grasos Monoinsaturados/farmacología , Conducta Alimentaria/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Aceite de Soja/farmacología , Accidente Cerebrovascular/patología , Animales , Antioxidantes/metabolismo , Presión Sanguínea/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Grasas de la Dieta/administración & dosificación , Ingestión de Líquidos/efectos de los fármacos , Ácidos Grasos Monoinsaturados/administración & dosificación , Lípidos/sangre , Masculino , Modelos Animales , Aceite de Brassica napus , Ratas , Ratas Endogámicas SHR , Aceite de Soja/administración & dosificación , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/fisiopatología , Análisis de SupervivenciaRESUMEN
BACKGROUND: Red wine contains a naturally rich source of antioxidants, which may protect the body from oxidative stress, a determinant of age-related disease. The current study set out to determine the in vivo effects of moderate red wine consumption on antioxidant status and oxidative stress in the circulation. METHODS: 20 young (18-30 yrs) and 20 older (>or= 50 yrs) volunteers were recruited. Each age group was randomly divided into treatment subjects who consumed 400 mL/day of red wine for two weeks, or control subjects who abstained from alcohol for two weeks, after which they crossed over into the other group. Blood samples were collected before and after red wine consumption and were used for analysis of whole blood glutathione (GSH), plasma malondialdehyde (MDA) and serum total antioxidant status. RESULTS: Results from this study show consumption of red wine induced significant increases in plasma total antioxidant status (P < 0.03), and significant decreases in plasma MDA (P < 0.001) and GSH (P < 0.004) in young and old subjects. The results show that the consumption of 400 mL/day of red wine for two weeks, significantly increases antioxidant status and decreases oxidative stress in the circulation CONCLUSION: It may be implied from this data that red wine provides general oxidative protection and to lipid systems in circulation via the increase in antioxidant status.
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Antioxidantes/metabolismo , Antioxidantes/farmacología , Estrés Oxidativo/efectos de los fármacos , Vino , Adulto , Envejecimiento/fisiología , Consumo de Bebidas Alcohólicas , Glucemia/metabolismo , Estudios Cruzados , Femenino , Glutatión/sangre , Humanos , Lípidos/sangre , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Oxidación-ReducciónRESUMEN
This review discusses studies investigating the effects of antioxidant supplementation on exercise-induced oxidative stress with a focus on the health implications. The aim is to determine antioxidant requirements for endurance athletes. Overall, differences in methodology make it difficult to compare the relatively small number of published studies on this topic. The types of studies needed to more adequately assess the health effects of antioxidant supplements in athletes (long-term interventions with hard end points) have not been done. Therefore, there is currently insufficient evidence to recommend antioxidant supplements for endurance athletes.
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Antioxidantes/administración & dosificación , Necesidades Nutricionales , Resistencia Física/fisiología , Suplementos Dietéticos , Estado de Salud , Humanos , Política Nutricional , Estrés Oxidativo/efectos de los fármacos , Resistencia Física/efectos de los fármacosRESUMEN
The aim of this study was to determine the effects of dietary antioxidant supplementation with alpha-tocopherol and alpha-lipoic acid on cyclosporine A (cyclosporine)-induced alterations to erythrocyte and plasma redox balance. Rats were randomly assigned to either control, antioxidant (alpha-tocopherol 1000 IU/kg diet and alpha-lipoic acid 1.6 g/kg diet), cyclosporine (25 mg/kg/day), or cyclosporine + antioxidant treatments. Cyclosporine was administered for 7 days after an 8 week feeding period. Plasma was analysed for alpha-tocopherol, total antioxidant capacity, malondialdehyde, and creatinine. Erythrocytes were analysed for glutathione, methaemoglobin, superoxide dismutase, catalase, glutathione peroxidase, glucose-6-phosphate dehydrogenase, alpha-tocopherol and malondialdehye. Cyclosporine administration caused a significant decrease in superoxide dismutase activity (P<0.05 control versus cyclosporine) and this was improved by antioxidant supplementation (P<0.05 cyclosporine versus cyclosporine + antioxidant; P<0.05 control versus cyclosporine + antioxidant). Animals receiving cyclosporine and antioxidants showed significantly increased (P<0.05) catalase activity compared to both groups not receiving cyclosporine. Cyclosporine administration induced significant increases in plasma malondialdehyde and creatinine concentration (P<0.05 control versus cyclosporine). Antioxidant supplementation prevented the cyclosporine induced increase in plasma creatinine (P<0.05 cyclosporine versus cyclosporine + antioxidant; P>0.05 control versus cyclosporine + antioxidant), however, supplementation did not alter the cyclosporine induced increase in plasma malondialdehyde concentration (P>0.05 cyclosporine versus cyclosporine + antioxidant). Antioxidant supplementation resulted in significant increases (P<0.05) in plasma and erythrocyte alpha-tocopherol in both of the supplemented groups compared to non-supplemented groups. In conclusion, dietary supplementation with alpha-tocopherol and alpha-lipoic acid enhanced the erythrocyte antioxidant defence and reduced nephrotoxicity in cyclosporine treated animals.
Asunto(s)
Antioxidantes/farmacología , Ciclosporina/toxicidad , Eritrocitos/efectos de los fármacos , Inmunosupresores/toxicidad , Ácido Tióctico/farmacología , alfa-Tocoferol/farmacología , Animales , Antioxidantes/administración & dosificación , Catalasa/metabolismo , Creatinina/sangre , Suplementos Dietéticos , Eritrocitos/enzimología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/prevención & control , Masculino , Oxidación-Reducción , Estrés Oxidativo , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , Ácido Tióctico/administración & dosificación , alfa-Tocoferol/administración & dosificaciónRESUMEN
Cyclosporine A-treated transplant recipients develop pronounced cardiovascular disease and have increased oxidative stress and altered antioxidant capacity in erythrocytes and plasma. These experiments investigated the time-course of cyclosporine A-induced changes to redox balance in plasma and erythrocytes. Rats were randomly assigned to either a control or cyclosporine A-treated group. Treatment animals received 25 mg/kg of cyclosporine A via intraperitoneal injection for either 7 days or a single dose. Control rats were injected with the same volume of the vehicle. Three hours after the final injections, plasma was analysed for total antioxidant status, alpha-tocopherol, malondialdehyde, and creatinine. Erythrocytes were analysed for reduced glutathione (GSH), alpha-tocopherol, methaemoglobin, malondialdehyde, and the activities of superoxide dismutase, catalase, GSH peroxidase, and glucose-6-phosphate dehydrogenase (G6PD). Cyclosporine A administration for 7 days resulted in a significant increase (P<0.05) in plasma malondialdehyde, methaemoglobin, and superoxide dismutase and catalase activities. There was a significant decrease (P<0.05) in erythrocyte GSH concentration and G6PD activity in cyclosporine A animals. There were no significant differences (P>0.05) between groups following a single dose of cyclosporine A in any of the measures. In summary, cyclosporine A alters erythrocyte redox balance after 7 days administration, but not after a single dose.