Genetically modified astronauts
The loss of bone tissue in weightlessness was prevented by genetic engineering
Sara Tavella from the University of Genoa and colleagues from other Italian research centers created genetically modified mice that produced the protein pleiotrophin in an amount exceeding the norm.
Pleiotrophin, being involved in many processes, contributes, in particular, to the formation of osteoblasts, young cells of the bone tissue of vertebrates, which turn into its main cells – osteocytes.
The increased production of pleiotrophin in experimental mice was due to the fact that the gene of this protein was part of a genetically engineered structure under the control of a certain human promoter of this gene.
Six rodents participated in the experiment on the ISS – three transgenic mice and three control mice. Rodents with increased pleiotrophin production lost 3 percent of bone tissue in 91 days, while the spine of ordinary mice lost 41.5 percent of its mass.
It is known that in conditions of weightlessness, or microgravity, in the absence of mechanical loads, bone tissue undergoes demineralization, loses calcium and phosphorus. Monthly bone loss in the lumbar region and in the tibia of astronauts ranges from 0.8 to one and a half percent. "Astronauts can lose 20 to 30 percent of their bone tissue in one trip," notes Sarah Tavella. "And although they do physical exercises in orbit and take calcium supplements to limit the harm caused by microgravity, it can be very difficult to return the bones to their previous state on Earth," the researcher quotes New Scientist.
The authors note that the possibilities observed in the experiment on mice to prevent bone loss with an increased content of pleiotrophin can be studied to use the information obtained in the preparation of astronauts.
Portal "Eternal youth" http://vechnayamolodost.ru09.04.2012