Stem cells in the pancreas still exist
Insulin is necessary for cells to assimilate the main source of energy – glucose. With type 1 diabetes, the blood sugar level of patients increases due to the inability of pancreatic beta cells located in the so-called islets of Langerhans to synthesize a sufficient amount of this hormone.
A large number of studies devoted to the search for hypothetical precursors of beta cells contained in the pancreas after birth ended in failure. Many researchers abandoned further searches after genetic tracing of the cell differentiation line provided evidence that the main source of new beta cells in the pancreas of adult mice are not progenitor stem cells, but temporarily dormant beta cells.
During the new work, Belgian scientists at the University of Brussels, led by Dr. Harry Heimberg, succeeded by cutting the duct through which digestive enzymes move from the pancreas to the intestine. Two weeks after the procedure, the number of beta cells in the pancreas of mice doubled. The usefulness of the newly formed cells was evidenced by a simultaneous increase in the amount of synthesized insulin. The authors suggest that the regenerative process they observed was triggered by inflammatory reactions developing in the gland overflowing with enzymes.
Scientists have also found that the production of new beta cells depends on the activity of the Neurogenin 3 (Ngn3) gene, which plays an important role in the formation of the pancreas during embryonic development. Based on the results obtained, the authors claim that the structure, gene expression and behavior of adult beta-cell progenitor cells are practically indistinguishable from the corresponding characteristics of embryonic progenitors.
The most difficult task at the moment is to extrapolate the results obtained to patients with diabetes. Despite the fact that the development of diabetes treatment methods remains a matter of the future, the authors believe that their discovery indicates the need to continue working in two directions: 1) isolation of progenitor cells and newly formed beta cells, their cultivation and differentiation in laboratory conditions for subsequent transplantation to patients with diabetes, and 2) development of a complex of factors capable of stimulating the division and differentiation of progenitor cells directly in the pancreas of patients suffering from complete or partial insulin deficiency.
Portal "Eternal youth" www.vechnayamolodost.ru based on the materials of ScienceDaily.
25.01.2008