‘Turtle’ cells antechamber of type 2 diabetes. This is what, in summary, researchers from the Polyclinic Gemelli Irccs Foundation – Catholic University have discovered who have closely followed the trajectory of type 2 diabetes, to understand what the ‘X factor is. ‘at the basis of its appearance. The study, published in the ‘Journal of clinical investigation’ (JCI) has in fact shown that patients who have an alteration in the first phase of insulin secretion (patients with ‘turtle’ cells), undergo the onset of type 2 diabetes. On the other hand, those who have ‘hare’ insulin-producing cells, even after the removal of half the pancreas, do not become diabetic. The research, which made it possible to identify this ‘key’ defect for the development of type 2 diabetes, is the result of the collaboration between the group led by Andrea Giaccari, head of the Center for Endocrine and Metabolic Diseases of the Gemelli Polyclinic Foundation and associate professor of Endocrinology at the Catholic University, Rome campus, and the one led by Sergio Alfieri, director of the Gemelli pancreatic surgical center, and full professor of general surgery at Cattolica. In particular – reports a note – the study demonstrated that a malfunction of the beta cells of the pancreas (those that produce insulin) is much more important for the development of type 2 diabetes, than a sudden reduction in their number, such as which is determined following a partial removal of the pancreas (partial pancreatectomy), which halves the amount of beta cells. And the dysfunction that can lead to diabetes is a slowed secretion of insulin in response to increased blood sugar by ‘tortoise’ beta cells, what experts call alteration of the first phase of insulin secretion. “In the natural history of insulin. onset of type 2 diabetes insulin resistance and insulin secretion deficiency change continuously over time – explains the first author of the study, Teresa Mezza, researcher in Endocrinology, Uoc Endocrinology and diabetology of Gemelli directed by Alfredo Pontecorvi – and it is impossible to understand which of the two variables is more important. With surgery we experimentally modify only one of the two variables, in the same way in all patients. With a partial pancreatectomy, in terms of the evolution of the diabetic disease, it is a bit like do in two months what nature does in 20 years ”. Surgical interventions are teaching or much about the genesis of diabetes; this study demonstrates that even by removing half a pancreas from a patient who has no insulin resistance (ie is not overweight / obese), nor insulin secretion deficiency, that subject will not become diabetic. For the purpose of maintaining a good blood sugar, therefore, it does not matter how much pancreas is removed, but that what remains works well. “The innovativeness of this line of research – explains Andrea Giaccari, senior author of the study – lies above all in not studying people who already have diabetes, but people who are at risk of developing it, comparing in vitro and in vivo data and trying to understand the mechanisms “. And the obesity pandemic that afflicts the world – concludes the note – is a great ‘detector’ of those who carry these cells with ‘slow’ reflexes, because obesity brings in another important risk factor for type 2 diabetes, insulin resistance, ie the inability of insulin target tissues and organs to respond to the commands of this hormone, to overcome which beta cells must produce more and more insulin.