Multifaceted therapeutic approaches for a multigenic disease

Diabetes is a severe chronic disease that affects approximately 200 million individuals worldwide, with extremely debilitating effects and considerably high health care costs. The two major classes of diabetes, known as type 1 (previously known as insulin-dependent or juvenile-onset diabetes) and type 2 (non-insulin-dependent diabetes), share common symptoms such as hyperglycemia and the development of long-term complications, but they differ in many aspects, including their etiopathogenesis. New insights suggest that overlapping factors, formerly considered typical hallmarks of each specific type, can coexist in the same diabetic patient, making it difficult to support a sharp distinction between the two classes and, more importantly, to adopt appropriate therapeutic solutions. In type 1 and type 2 diabetic subjects, but even more in patients with combined types, multiple genetic factors play a role in determining susceptibility or resistance to the disease, and perhaps also the time of onset, the severity of the symptoms, the possibility of developing complications and, ultimately, the response to therapy. In this review, the therapeutic treatments currently under investigation, as well as the curative strategies envisioned for future applications, are reanalyzed considering the multifaceted and complex aspects of a continuum that can be just defined as "diabetes."