The islets of Langerhans are infiltrated by CD4+, CD8+ T lymphocytes, NK cells, B lymphocytes, dendritic cells, macrophages and neutrophils, similar to the disease process in humans. In addition to sex, breeding conditions, gut microbiome composition or diet also influence the onset of T1D.The BioBreeding Diabetes-Prone (BB) rat is another widely used spontaneous experimental model for T1D. The onset of diabetes occurs, in up to 90% of individuals (regardless of sex) at 8–16 weeks of age. During insulitis, the pancreatic islets are infiltrated by T lymphocytes, B lymphocytes, macrophages, and NK cells, with the difference from the human course of insulitis being that CD4 + T lymphocytes are markedly reduced and CD8 + T lymphocytes are almost absent. The aforementioned lymphopenia is the major drawback of this model. The disease is characterized by hyperglycemia, hypoinsulinemia, weight loss, ketonuria, and the need for insulin therapy for survival. BB Rats are used to study the genetic aspects of T1D and are also used for interventional studies and diabetic nephropathy studies.LEW-1AR1 / -iddm rats are derived from congenital Lewis rats and represent a rarer spontaneous model for T1D. These rats develop diabetes at about 8–9 weeks of age with no sex differences unlike NOD mice. In LEW mice, diabetes presents with hyperglycemia, glycosuria, ketonuria, and polyuria. The advantage of the model is the progression of the prediabetic phase, which is very similar to human disease, with infiltration of islet by immune cells about a week before hyperglycemia is observed.
In addition, constant low levels of insulin are achieved with one or two daily doses of long-acting insulin, or by steady infusion of low insulin levels by an insulin pump. The exact dose of insulin appropriate for each injection depends on the content of the meal/snack, and the individual persons sensitivity to insulin, and is therefore typically calculated by the individual with diabetes or a family member by hand or assistive device (calculator, chart, mobile app, etc.). People unable to manage these intensive insulin regimens are sometimes prescribed alternate plans relying on mixtures of rapid- or short-acting and intermediate-acting insulin, which are administered at fixed times along with meals of pre-planned times and carbohydrate composition.The only non-insulin medication approved by the U.S. Food and Drug Administration for treating type 1 diabetes is the amylin analog pramlintide, which replaces the beta-cell hormone amylin. Addition of pramlintide to mealtime insulin injections reduces the boost in blood sugar after a meal, improving blood sugar control. Occasionally, metformin, GLP-1 receptor agonists, Dipeptidyl peptidase-4 inhibitors, or SGLT2 inhibitor are prescribed off-label to people with type 1 diabetes, although fewer than 5% of type 1 diabetics use these drugs. Lifestyle
Besides insulin, the major way type 1 diabetics control their blood sugar is by learning how various foods impact their blood sugar levels. This is primarily done by tracking their intake of carbohydrates – the type of food with the greatest impact on blood sugar.