ConclusionUnderstanding the complexity of the molecular and biochemical bases of insulin impairment, as well as microvascular diseases in diabetes mellitus, is carried out in a method using conceptualization where consideration of the interactions, in the case of insulin dysfunction and resistance, the interconnections and correlations between glucose, insulin signaling, with associated molecules and substrates that regulate various tissues of importance metabolic are key approaches to understanding these pathways. With the different molecules involved, participating in both normal and dysfunctional pathways and mechanisms, the intracellular processing of the signal was ensured by the inducer, in that of insulin where it would bind to the substrate of the insulin receptor, l IRS. Other molecules, consisting of PK13, PKB and PKC and their derivatives and isotopes, were also of great importance due to the strong evidence demonstrating that dysfunction of these proteins in their homeostatic form contributed to the overall process of resistance to insulin. Regarding retinopathy, the leading cause of blindness in diabetic patients, the molecular basis and accreditation of the resulting pathology is primarily due to the polyol pathway, in which glucose is reduced to sorbitol, and then transformed into fructose. This mechanism becomes active when glucose levels increase abnormally, the cellular level of toxicity occurring in diabetic hyperglycemia where the products of this pathway and the associated cofactors and substrates that contribute to it, such as aldose reductase in the step limiting of the enzymatic pathway, demonstrate that abnormalities due to retinopathy are highly polymorphic to the immune system, which include molecules such as HLA which is classified as a dimeric class 1 protein molecule, with the intended function of presenting antigenic peptides to CD8 T lymphocytes. (Mark A. Atkinson, Noel K. Maclaren, 1994) Second, HLA class II are also known to be dimeric, while their characteristic perception demonstrates constitutive expression or enhanced induction on the surface of antigen-presenting cells. The interaction occurring between a cell which possesses an HLA molecule in contact with an antigenic peptide and a T lymphocyte, in the presence of a receptor, would demonstrate a process where the recognition of HLA and the peptide forming a complex, would result in the establishment of activation and proliferation of T lymphocytes where this immune response is the basis of almost all immune responses. (Brand A.