Effects of 21 days of bed rest, with or without artificial gravity, on nutritional status of humans.

Spaceflight and bed rest models of microgravity have profound effects on physiological systems, including the cardiovascular, musculoskeletal, and immune systems. These effects can be exacerbated by suboptimal nutrient status, and therefore it is critical to monitor nutritional status when evaluating countermeasures to mitigate negative effects of spaceflight. As part of a larger study to investigate the usefulness of artificial gravity as a countermeasure for musculoskeletal and cardiovascular deficits during bed rest, we tested the hypothesis that artificial gravity would have an effect on some aspects of nutritional status. Dietary intake was recorded daily before, during, and after 21 days of bed rest with artificial gravity (n = 8) or bed rest alone (n = 7). We examined body composition, hematology, general blood chemistry, markers of oxidative damage, and blood levels of selected vitamins and minerals before, during, and after the bed rest period. Several indicators of vitamin status changed in response to diet changes: serum alpha- and gamma-tocopherol and urinary 4-pyridoxic acid decreased (P < 0.001) and plasma beta-carotene increased (P < 0.001) in both groups during bed rest compared with before bed rest. A decrease in hematocrit (P < 0.001) after bed rest was accompanied by a decrease in transferrin (P < 0.001), but transferrin receptors were not changed. These data provide evidence that artificial gravity itself does not negatively affect nutritional status during bed rest. Likewise, artificial gravity has no protective effect on nutritional status during bed rest.

[1]  J. Andrade,et al.  Minimizing interferences in the quantitative multielement analysis of trace elements in biological fluids by inductively coupled plasma mass spectrometry. , 1997, Clinical chemistry.

[2]  Nutrition Board,et al.  Dietary Reference Intakes for Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline , 2000 .

[3]  Scott M Smith,et al.  Stability of i-Stat EC6+ cartridges: effect of storage temperature on shelf life. , 2004, Clinical chemistry.

[4]  Maurice E. Shils,et al.  Modern Nutrition in Health and Disease , 1965, Diabetes.

[5]  Scott M Smith,et al.  The nutritional status of astronauts is altered after long-term space flight aboard the International Space Station. , 2005, The Journal of nutrition.

[6]  K. Kondo,et al.  The effects of 20 days bed rest on serum lipids and lipoprotein concentrations in healthy young subjects. , 1997, Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology.

[7]  C S Leach-Huntoon,et al.  Decreased production of red blood cells in human subjects exposed to microgravity. , 1995, The Journal of laboratory and clinical medicine.

[8]  M. Kuo,et al.  Zinc and copper balances in healthy adult males during and after 17 wk of bed rest. , 1993, The American journal of clinical nutrition.

[9]  T. Guilarte,et al.  Response of vitamin B-6 content of muscle to changes in vitamin B-6 intake in men. , 1991, The American journal of clinical nutrition.

[10]  C. Genestar,et al.  Inhibitors of calcium oxalate crystallization and urolithiasis. , 1992, Urologia internationalis.

[11]  J. Davis-Street,et al.  Assessment of a portable clinical blood analyzer during space flight. , 1997, Clinical chemistry.

[12]  M. Beal,et al.  A carbon column-based liquid chromatography electrochemical approach to routine 8-hydroxy-2'-deoxyguanosine measurements in urine and other biologic matrices: a one-year evaluation of methods. , 1999, Free radical biology & medicine.

[13]  Scott M Smith,et al.  Nutritional status changes in humans during a 14-day saturation dive: the NASA Extreme Environment Mission Operations V project. , 2004, The Journal of nutrition.

[14]  R. Pietrzyk,et al.  Alterations in renal stone risk factors after space flight. , 1993, The Journal of urology.

[15]  Helen W. Lane,et al.  Nutrition in spaceflight and weightlessness models , 2000 .

[16]  Scott M Smith.  Red blood cell and iron metabolism during space flight. , 2002, Nutrition.

[17]  G. Block,et al.  Nutrititional Status Assessment of International Space Station Crew Members , 2005 .

[18]  P. Trumbo,et al.  Dietary reference intakes: vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium, and zinc. , 1998, Journal of the American Dietetic Association.

[19]  G Block,et al.  Nutritional status assessment in semiclosed environments: ground-based and space flight studies in humans. , 2001, The Journal of nutrition.

[20]  C. Su,et al.  Effect of magnesium on calcium oxalate urolithiasis. , 1991, The Journal of urology.

[21]  T. Stein.  Space flight and oxidative stress. , 2002, Nutrition.

[22]  F. G. Benedict,et al.  A biometric study of basal metabolism in man , 2010 .

[23]  O. Castagna,et al.  Bubble formation and endothelial function before and after 3 months of dive training. , 2009, Aviation, space, and environmental medicine.

[24]  J. Garvin,et al.  A high-salt diet stimulates thick ascending limb eNOS expression by raising medullary osmolality and increasing release of endothelin-1. , 2005, American journal of physiology. Renal physiology.

[25]  J. Pollock,et al.  Evidence for endothelin involvement in the response to high salt. , 2001, American journal of physiology. Renal physiology.

[26]  S. Margolis,et al.  Measurement of ascorbic acid in human plasma and serum: stability, intralaboratory repeatability, and interlaboratory reproducibility. , 1996, Clinical chemistry.

[27]  H. Yokogoshi,et al.  Changes in vitamin A status following prolonged immobilization (simulated weightlessness). , 1992, Life sciences.

[28]  T P Stein,et al.  Hormonal Modulation of Food Intake in Response to Low Leptin Levels Induced by Hypergravity , 2001, Experimental biology and medicine.

[29]  R. Pietrzyk,et al.  Renal stone risk assessment during Space Shuttle flights. , 1997, The Journal of urology.

[30]  C. Long,et al.  Validity of 3-methylhistidine excretion as an indicator of skeletal muscle protein breakdown in humans. , 1988, Metabolism: clinical and experimental.

[31]  J. Mcaleer.  Nutrition in space. , 1967, Journal. Indianapolis District Dental Society.

[32]  Nutrition Board,et al.  Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids , 2005 .

[33]  R. Wolfe,et al.  Amino acid supplementation alters bone metabolism during simulated weightlessness. , 2005, Journal of applied physiology.

[34]  H W Lane,et al.  Energy requirements for space flight. , 1992, The Journal of nutrition.

[35]  D. Costill,et al.  Modeling short (7 hour)- and long (6 week)-term kinetics of vitamin B-6 metabolism with stable isotopes in humans. , 2003, Advances in experimental medicine and biology.

[36]  Scott M Smith,et al.  Nutritional biochemistry of spaceflight. , 2014, Advances in clinical chemistry.

[37]  T. Driscoll,et al.  Control of red blood cell mass in spaceflight. , 1996, Journal of applied physiology.

[38]  its Panel on Folate,et al.  FOOD AND NUTRITION BOARD , 1998 .

[39]  Scott M Smith,et al.  Nutritional status assessment before, during, and after long-duration head-down bed rest. , 2009, Aviation, space, and environmental medicine.

[40]  T P Stein,et al.  Energy expenditure and balance during spaceflight on the space shuttle. , 1999, The American journal of physiology.

[41]  Scott M Smith,et al.  Natural calcium isotopic composition of urine as a marker of bone mineral balance. , 2007, Clinical chemistry.

[42]  L. E. Warren,et al.  Effects of 2G exposure on lean and genetically obese Zucker rats. , 2000, Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology.

[43]  I M Buzzard,et al.  Sources of data for developing and maintaining a nutrient database. , 1988, Journal of the American Dietetic Association.

[44]  Scott M Smith,et al.  Nutritional status is altered in the self-neglecting elderly. , 2006, The Journal of nutrition.

[45]  T. Driscoll,et al.  Destruction of newly released red blood cells in space flight. , 1996, Medicine and science in sports and exercise.

[46]  S. Zwart,et al.  Nutritional Assessment During a 14-d Saturation Dive: the NASA Extreme Environment Mission Operation V Project , 2006 .

[47]  S. Smith,et al.  Nutritional biochemistry of space flight. , 2009, Life support & biosphere science : international journal of earth space.

[48]  C. Wade,et al.  Resting energy expenditure of rats acclimated to hypergravity. , 2002, Aviation, space, and environmental medicine.

[49]  Robert M. Russell,et al.  Dietary Reference Intakes for Vitamin A , Vitamin K , Arsenic , Boron , Chromium , Copper , Iodine , Iron , Manganese , Molybdenum , Nickel , Silver , Vanadium , and Zinc , 2022 .

[51]  D. Costill,et al.  Pyridoxic acid excretion during low vitamin B-6 intake, total fasting, and bed rest. , 1995, The American journal of clinical nutrition.

[52]  T P Stein,et al.  Oxidant damage during and after spaceflight. , 2000, American journal of physiology. Endocrinology and metabolism.

[53]  Peggy A. Whitson,et al.  The Risk of Renal Stone Formation during and after Long Duration Space Flight , 2001, Nephron.

[54]  J. Greenleaf,et al.  Insulin and glucose responses during bed rest with isotonic and isometric exercise. , 1977, Journal of applied physiology: respiratory, environmental and exercise physiology.