Prolonged skeletal unloading through bedrest results in bone loss similar to that observed in elderly osteoporotic patients, but with an accelerated timeframe. This rapid effect on weight-bearing bones is also observed in astronauts who can lose up to 2% of their bone mass per month spent in Space. Despite the important implications for Spaceflight travelers and bedridden patients, the exact me...

Microgravity-induced orthostatic intolerance (OI) continues to be a primary concern for the human space program. To test the hypothesis that exposure to simulated microgravity significantly alters autonomic nervous control and, thus, contributes to increased incidence of OI, we employed the cardiovascular system identification (CSI) technique to evaluate quantitatively parasympathetic and sympa...

Exposure to microgravity (weightlessness) is known to cause rapid bone and muscle losses. We have used the hind limb-suspended (HLS) rat model to simulate microgravity-induced musculoskeletal losses in order to assess resulting hormonal changes and to develop a novel pharmacological countermeasure. Previously, we demonstrated significant decreases in circulatory hormonal levels [serum thyroxin,...

microgravity trabecular compartments during simulated Bone loss patterns in cortical, subcortical, and You might find this additional info useful... those papers emphasizing adaptive and integrative mechanisms. It is published 12 times a year (monthly) by the American publishes original papers that deal with diverse areas of research in applied physiology, especially

Immune system adaptation during spaceflight is a concern in space medicine. Decreased circulating leukocytes observed during and after space flight infer suppressed immune responses and susceptibility to infection. The microgravity aspect of the space environment has been simulated on Earth to study adverse biological effects in astronauts. In this report, the hindlimb unloading (HU) model was ...

Since human beings could travel beyond the earth atmosphere, scientists started to investigate the effect of microgravity on human cells. Microgravity has different effects on normal and cancer cells, but the related mechanisms are not well-known till now. The aim of the present review is to focus on the consequences of exposing the cancer cells to reduced gravity. Some cancer cells organize th...

Plasma volume is reduced by 10-20% within 24-48 h of exposure to simulated or actual microgravity. The clinical importance of microgravity induced hypovolemia is manifested by its relationship with orthostatic intolerance and reduced maximal oxygen uptake (VO2max) after return to one gravity (1G). Since there is no evidence to suggest that plasma volume reduction during microgravity is associat...

Background: The relationship between microgravity and parathyroid hormone (PTH), a keystone of bone mineral density, remains controversial. Bone loss is prominent, ongoing issue in spaceflight, PTH has been suggested as treatment for microgravity-induced osteopenia, indicating the importance this hormone. This systematic review meta-analysis aimed to evaluate association exposure production PTH...

There are a multitude of physiological adaptations to microgravity, involving the cardiovascular, neuromuscular, and neuroendocrine systems. Some of these adaptations lead to cardiovascular deconditioning on return to normal gravity, posing a threat to human functional integrity after long-term spaceflight. Animal models of microgravity, e.g., tail suspension in rats, have yielded important inf...