The use of stem cells in the therapy involves at first the thorough study of the signalling mechanisms in the formation of the pancreatic beta cells from the embryonic stem cells, mainly the Notch signalling mechanism, which stimulates the creation of the beta cells in the developing foetus after inhibiting the same at first. With the study of the various signalling processes within the body, the scientists have succeeded in the formation of functional beta cells in pancreas, which secrete insulin, from the embryonic stem cells. Stem cells could also provide an alternate treatment by helping in the pancreatic recovery, thereby helping in the replenishment of the beta cells secreting insulin. It has been proved by the successful study in mouse models that when the gene for the vascular endothelial growth factor (VEGF) is expressed in the modified bone marrow stem cells, the pancreatic recovery is sustained with the formation of new beta cells, thereby helping in insulin production. The modified stem cells help in the formation of new blood vessels and activate the genes responsible for insulin production.
Type I diabetes results due to autoimmune disorder, in which the immune cells affect and destroy the pancreatic beta cells, thereby affecting insulin production. Research studies have shown that the aggression of the immune system can be treated with the combination of stem cell therapy and immune suppression drugs. In this treatment, the abnormal immune system cells are suppressed and destroyed by the drugs and are then, replaced by the immature stem cells, which differentiates into normal immune system cells, thereby preventing the destruction of beta cells and help cure Type I diabetes. Cord blood stem cells have also been used for the treatment of the autoimmune disorder of Diabetes, which follows the ‘Stem cell education therapy’. In this procedure, the cord blood stem cells of the healthy donor secreted the Autoimmune regulator (AIRE) that effected changes in the lymphocytes of the patient when they are co-incubated, thereby preventing the autoimmune attack on the pancreatic beta cells and helping in their recovery.
Research studies have shown that neural stem cells from the hippocampus and olfactory bulb were successful in differentiating into pancreatic beta cells when transplanted into the pancreas of diabetic rats and could secrete insulin, thereby helping in the diabetes treatment. This could provide a solution for the non-availability of donors of stem cells or pancreas as the patient himself could be the donor of neural stem cells essential for the treatment. However, in-depth research is essential for translating the studies on rodents to that on human patients.
In the treatment of diabetes, the stem cell therapy is indicated in almost all the stages of the diseases. However, it is most effective when applied in the initial onset of the disease; in case of renal failure in the diabetes patients; immunodeficiency disorders; development of Diabetes mellitus Type II, etc. Although, the stem cell therapy may prove to give beneficial results on the sufferers, but the scientists need to study thoroughly the possible side effects on the other mechanisms within the body, which is possible only by carrying out further scientific investigation on the subject. The pathways of the differentiation processes must be elucidated properly for the translational studies on higher animals as the research has been carried out mainly on rodent models. A revolution in the world of therapeutics can be expected in future, keeping the vast scope of stem cell research in mind.