Bald Mice and Men
According to a recent study, engineered hair follicles patched into skin can be coaxed to connect to surrounding tissue and to grow hair in an organized way. The study was conducted at the University of Science in Chiba, Japan and describe in the April 17 Nature Communications.
Hair follicles develop when two different types of cells — epithelial and mesenchymal cells — interact with each other. Epithelial cells grow very quickly and shed, while mesenchymal cells direct epithelial cells to make a follicle.
Previously, Takashi Tsuji, study coauthor, and colleagues had bioengineered follicles and hair shafts in the lab using epithelial and mesenchymal cells from mouse embryos.Until now, it was unclear whether these organized clusters of cells would make normal hair if inserted into mouse skin.
In this study, the team transplanted a group of the engineered follicles into the skin on the backs of hairless mice.After about two weeks, hairs began to sprout. Under the microscope, the hair grown from the bioengineered mouse follicles resembled normal hair, and the mouse follicles went through the normal cycle of growing hair, shedding and making new hair.
When researchers injected the region around the bioengineered follicle with acetylcholine, a drug that causes muscles to contract, the hairs perked up, suggesting that the transplanted follicles had integrated with surrounding muscle and nerves like normal hair follicles.
The study results also mark a step forward in efforts to regenerate organs such as salivary glands that form in a process similar to hair early in their development.
“It’s exciting because it shows a cell-based approach for treating hair loss is maybe feasible,” says George Cotsarelis, MD, a dermatologist at the University of Pennsylvania in Philadelphia.
Dr. Cotsarelis, is also senior author of a study conducted at the University of Pennsylvania School of Medicine which showed that bald men have just as many stem cells in their hair follicles as those with a full healthy set of hair, but the “bald” stem cells did not contain normal levels of progenitor cells.It is the progenitor cells that cause hair to be thick. Study findings were published in the Journal of Clinical Investigation.Researchers noted that stem cells are still present and may need to be “woken up” and thus male baldness may be reversible.
In a follow-on study, Dr. Cotsarelis and researchers at the Perelman School of Medicine at the University of Pennsylvania discovered that an abnormal amount of Prostaglandin D2 (PGD2) might be the stimulus that sets male pattern baldness in motion.The researchers identified the PGD2 receptor as GPR44.Once identified, finding a drug that will block this receptor could prevent baldness and provide relief to men and women suffering with hair loss and thinning.
According to Dennis Lox, MD, regenerative medicine techniques, particularly platelet-rich plasma, have been used to treat baldness for some time, so researching the use stem cells to treat baldness is no surprise.Continued interest in the field of regenerative medicine and stem cell therapy will pave the way for a variety of new developments in all fields of medicine.
Dennis M. Lox, MD, has been sucessfully preforming stem cell therapy for several years. Dr. Lox is located in the Tampa bay area in Clearwater, Florida
Information contained in this blog is intended for educational purposes only and not for medical diagnosis or treatment. If you have a medical concern or issue, please consult with your physician.