About this Research Topic
Physiological deconditioning changes induced by spaceflight are similar to those that occur in aging, thus leading to greater incidence of syncope and falls and to decrease in quality of life. The planned research topic examines effects of gravitational changes on human physiology, with applications to clinical medicine. The proposed topic aims at developing research in the area of gravitational physiology, aging and medicine, promote national and international networks including capacities to promote student-oriented learning.
Gravitational forces are known to influence human physiology and actions. For instance, upon standing up, approx. 500ml of blood move into the lower limbs within seconds. This can compromise the venous return, and hence blood pressure, leading to falls. Further, gravity influences the way we interact with the environment. Fortunately, the body compensates rapidly to maintain mean arterial pressure and prevents falls and the brain is able to predict the consequences of the effects of gravity so as to produce smooth actions.
Gravitational effects become more pronounced when astronauts return from the microgravity environment of spaceflight or in older persons. In both of these cases, there is a higher incidence of orthostatic intolerance and syncope leading to falls related events such as fractures or prolonged hospitalization.
Spaceflight and Aging
The microgravity environment of spaceflight causes cardiovascular, neurovestibular and muskulo-skeletal changes. The latter include bone loss and muscle atrophy. These physiological deconditioning changes are similar to those that occur in aging, thus leading to greater incidence of syncope and falls. Falls, in turn, are associated with high morbidity as they may lead to head injuries and/or bone fractures. In the elderly, fractures of the femur are often associated with long-term immobilization, from which the patients may not be able to recover. Therefore, spaceflight deconditioning is similar to aging.
Furthermore, studies related to spaceflight deconditioning often uses ground-based analogues such as immobilization/bedrest to study the effects of long-term spaceflight. As immobilization is a common feature in older persons, data from immobilization studies are useful for understanding the processes that occur in these more and more represented populations. For instance, postural control deficiencies and orthostatic hypotension are major contributors to falls in the elderly. It would be logical to propose that integrating information from Earth and space provides an avenue for developing new perspectives. For example, scientific insights and methodologies developed in space science research of orthostatic intolerance can be exploited to study cardiovascular, cerebrovascular, and postural sensory motor control systems in male and females.
The areas covered in this research topic will include aspects related to physiology of gravitational (un-)loading, effects of immobilization, aging related physiological deconditioning, mathematical modeling of physiological systems as well as how knowledge of life in space- and the countermeasures developed in space to overcome spaceflight induced effects- can help life on Earth. Included in this research topic will be both original research articles and reviews from experts.
Keywords: Gravity, spaceflight, aging, countermeasures, hypergravity, hypogravity
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