It had slipped my mind that the last Life Extension Magazine included a pop-sci article on a range of regenerative medicine research. It's a publication in which reading between the ads and junk is something of an art form - as for all the successful old school pro-healthy life extension businesses - but at least it all ends up online for folks to pick over at greater leisure:
Researchers at the Wistar Institute in Philadelphia, PA, are studying a unique strain of mouse that can heal wounds by regeneration. After a hole is pierced in the mouse's ear (a typical laboratory identification procedure), it closes with no evidence that a hole was ever present. These animals, known as Murphy/Roths/Large mice, or MRL mice, are so named to denote the two scientists who originally bred them, as well as their unusually large size. MRL mice are genetically unique, and scientists are researching them to elucidate the genetics of regeneration, hoping to gather information that can be used to help humans.
When the Wistar scientists induced heart injury in both MRL mice and typical mice, they found that the MRL mouse heart returned to normal, whereas the typical mouse heart was scarred. Human hearts scar following injury from heart attack, and the scarring response contributes to chronic heart disease and death. The healing response in the MRL mouse, however, differed greatly from that of the typical mouse. The MRL mouse displayed early movement of cardiomyocytes into the wound site, and DNA synthesis and proliferation of these cells. The MRL mouse heart also demonstrated better revascularization (restoration of blood supply) at the site of injury, which is necessary to help cells thrive and avoid death. According to the scientists, the MRL mouse studies demonstrate that "mammalian hearts have significant capacity to regenerate."
Millions of dollars are spent each year to develop tissue engineering products and procedures. In fact, some engineered tissues have already been approved by the FDA. One of the first tissues to be engineered and used clinically is bone. Engineered bones, cartilage, tendons, and ligaments may benefit people who suffer from bones that will not fuse, defective tendons, or arthritic joints, as well as those who need dental implants (which require strong bone tissue). These regenerated tissues will one day eliminate the need for standard therapy, which includes stainless steel, cobalt chrome, and bone grafting.
Scientists are also developing engineered skin, which will help treat massive burns, chronic problem wounds that are difficult to heal (common in people with diabetes), and vitiligo (a disease of discolored skin). Although heart valves have been engineered, the valves failed when they were implanted. A whole bladder has been engineered and transplanted in a dog. The bladder appeared to be normal and demonstrated normal function. An engineered bladder has not been evaluated in humans. Nearly every body tissue is being engineered for future applications in medicine.