A specific type of stem cell called mesenchymal stem cells has shown significant promise for therapeutics against a host of diseases, and now scientists have found that they can improve the therapeutic impact of these stem cells through something called hypoxia preconditioning. They have published their findings in a journal called Cell Death and Disease.
Previous research has found that, though helpful for therapies, the effectiveness of mesenchymal stem cells is often limited by certain physiological conditions. For instance, DNA damage, cell death, and harm to tissue often persist because reactive oxygen species are produced in response to disease or injury. Insufficient nutrient levels can also minimize the therapeutic potential of mesenchymal stem cells. Studies performed to overcome these limitations by genetically modifying mesenchymal stem cells have demonstrated that this particular approach comes with its own difficulties, including toxicity and unwanted side effects.
Certain injuries lead to a shortage of blood supply to some tissue areas. When this occurs, the oxygen levels in those tissues can become severely limited in what is known as hypoxia. Hypoxia can lead to cell death and can also make it harder for stem cells to differentiate if they are applied for therapy. However, research has shown that preconditioning cells to lower oxygen level conditions can enable them to later withstand more severe hypoxia. Based on these observations, a team of scientists, led by Sang Hun Lee, hypothesized that preconditioning mesenchymal stem cells may help them survive and proliferate once they are transplanted into injured tissue.
To test their idea, the scientists preconditioned mesenchymal stem cells from people’s fat tissue to low oxygen levels and then transplanted the cells into mice whose blood supply had been cut off to certain tissues. When they compared the impact of transplanting these preconditioned cells to transplanting cells that were not preconditioned, they found that the preconditioned cells survived and proliferated at higher rates and that they were more effective in helping the mice recover functionally. These results add to the breadth of research that suggests that stem cells may have an array of therapeutic applications and that any limitations that arise may be able to be addressed by combining stem cell transplantation with other strategies.