Space flight is associated with rapid decreases of undercarboxylated Osteocalcin and increases of markers of bone resorption without changes in their circadian variation: Observations in two cosmonauts
| Autor: | Anne Caillot-Augusseau, Laurence Vico, Christian Alexandre, Marie-Hélène Lafage-Proust, Dimitri Voroviev, Armin Zitterman, Martina Heer, Jean-Claude Souberbielle |
|---|---|
| Rok vydání: | 2000 |
| Předmět: |
Adult
Male medicine.medical_specialty Time Factors Osteocalcin Clinical Biochemistry bone Bone and Bones Collagen Type I Bone resorption Bone remodeling vitamin K chemistry.chemical_compound Internal medicine medicine Humans Circadian rhythm Amino Acids Bone Resorption Pyridinoline biology Chemistry Biochemistry (medical) Space medicine biomarkers Space Flight Alkaline Phosphatase microgravity Circadian Rhythm Resorption Endocrinology biology.protein Astronauts Collagen Peptides Procollagen Type I collagen |
| Zdroj: | Scopus-Elsevier Europe PubMed Central |
| Popis: | Background: Microgravity induces bone loss by mechanism(s) that remain largely unknown.Methods: We measured biochemical markers related to bone remodeling in two cosmonauts before, during, and after 21- and 180-day space flights, respectively.Results: During both flights, type I procollagen propeptide and bone alkaline phosphatase decreased as early as 8 days after launch. Undercarboxylated osteocalcin percentage increased early and remained high during both flights. Vitamin K supplementation restored carboxylation of osteocalcin during the long-term flight. Urinary and serum C-telopeptide of type I collagen (CTX) increased as early as day 8 of the flights; the increase was greater in serum than in urine. Pyridinoline, free deoxypyridinoline, and N-telopeptide increased less than CTX during the short-term space flight. The circadian rhythm of bone resorption assessed by urine CTX and free deoxypyridinoline was not altered by microgravity.Conclusion: Vitamin K metabolism or action and bone remodeling may be altered in cosmonauts. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|