This chart says that old stem cells, that give birth to blood cells, have much much more Wnt5a protein than the young stem cells. The canonical Wnt signaling cascade changes to the non-canonical one that produces more Wnt5a product. This observation was done by a group of scientists at the universities of Ulm and Muenchen, Germany and was published in Nature. So, why is this such a special observation?
Well, because it gives us a clue to what can be done to rejuvenate our blood producing stem cells. We can “turn off” the Wnt5a gene and make the old stem cells young again, which was successfully done by the authors of the experiment. The researchers took the short hairpin RNA and inserted it into the stem cells using a lentivirus. This hairpin RNA blocks translation of the Wnt5a protein sort of like a blank plug. So, these cells were transplanted into mice and those mice showed improved B lymphopoiesis and peripheral blood differentiation profile overall more similar to the one characteristic of young mice. This can one day become a therapy for humans. We could periodically receive such transplantations of our own hematopoietic stem cells, rejuvenated using gene therapy and we could have young blood production again.
Continuing the series of charts describing the mechanisms of aging. Here you can download the pdf the chart about aging of stem cells. Take a look at how telomere shortening, oxidative stress and impaired stem cell niche regulation influences our stem cells: reduces the number of dormant stem cells, reduces their engrafting capacities and leads to aberrant, meaning improper, differentiation.
In a pioneering operation, a British teenager has received a new windpipe grown from her own stem cells and has now been discharged after the procedure in Italy. This actually saved her life as she was suffering from a rare form of tracheal cancer.
“The patient was able to speak again only a few days after the surgery”, said Dr. Paolo Macchiarini, professor of surgery at the University of Barcelona in Spain and the head surgeon in the case.
Macchiarini and his team regenerated tissue from the patients nose and bone marrow stem cells to create a trachea biologically identical to her original organ. The girl’s stem cells were grafted on to the cartilage of donor trachea that had been stripped of its own cells. Because the new trachea contained no cells from another person, no anti-rejection drugs were needed.
Injured mice that were treated with stem cell therapy experienced muscle repair and enhancement, creating mighty mice with bulky muscles that stayed big and strong for the rest of their lives, U.S. researchers said this past week. These findings could lead to new treatments for human diseases that would help people resist the gradual erosion of muscle strength that comes with aging, Bradley Olwin, of the University of Colorado at Boulder, and colleagues reported in the journal Science Translational Medicine.