Trip to Mars could end with dialysis

Space exploration, particularly extended space travel to destinations such as Mars, presents complex medical challenges for astronauts. As we aspire to conquer new space frontiers, it is crucial to understand the profound physiological implications of prolonged exposure to microgravity and galactic cosmic radiation. However, a recent study from University College London has shed light on the potential deleterious effects of extended space travel on astronauts’ kidneys.

The effects of prolonged space travel on the kidneys

The kidneys are vital organs that perform several essential functions to maintain the internal balance of the human body, called homeostasis. Their main role is to remove waste and excess fluid from the blood in the form of urinea crucial process for maintaining a stable chemical composition in the body. By regulating body fluids, the kidneys also adjust blood pressure by controlling the amount of water retained or eliminated by the body. In addition to their filtration function, the kidneys play a key role in electrolyte balance such as sodium, potassium, calcium and phosphorus in the blood. These minerals are essential for the proper functioning of cells, muscles and nerves. By adjusting the concentrations of these electrolytes, the kidneys therefore ensure the proper functioning of many biological processes. The kidneys are also involved in the blood pH regulation by controlling the amount of acid and base in the body. This ability is crucial for the proper functioning of enzymes and other chemical processes in the human body. Finally, the kidneys produce hormones important ones such as erythropoietin, which stimulates the production of red blood cells in the bone marrow, and the active form of vitamin D, which is essential for calcium absorption and maintaining bone health. These organs are therefore essential for our body. A question then arises, while several actors prepare for long-term missions in space, and in particular on Mars: will our kidneys be able to hold out?
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Bad news

Recent studies conducted by University College London (UCL) have explored this question in unprecedented depth, revealing insights relevant to the future of space exploration. Among the most concerning observations are the structural changes observed in the kidneys of astronauts and rodents exposed to microgravity and galactic cosmic radiation (GCR), similar to those encountered during voyages to Mars. In the absence of Earth‘s gravity, renal tubules responsible for calcium and salt balance actually show signs of shrinkagea phenomenon that could lead to complications such as increased formation of kidney stones. Additionally, research has revealed that GCRs can induce permanent kidney damage and an reduced kidney function in rodents exposed to simulated long-duration Mars missions. The results of these studies thus highlight the urgency of developing innovative strategies to protect astronauts’ renal function during extended space travel. Although complete protection against GCR may be out of reach with current technologies, technological and pharmaceutical approaches could offer potential solutions. Details of the study are published in Nature Communications.