Insulin is a peptide hormone produced by beta cells of the pancreatic islets; it is considered to be the main anabolic hormone of the body. It regulates the metabolism of carbohydrates, fats and protein by promoting the absorption of carbohydrates, especially glucose from the blood into liver, fat and skeletal muscle cells. In these tissues the absorbed glucose is converted into either glycogen via glycogenesis or fats (triglycerides) via lipogenesis, or, in the case of the liver, into both. Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood. Circulating insulin also affects the synthesis of proteins in a wide variety of tissues. It is therefore an anabolic hormone, promoting the conversion of small molecules in the blood into large molecules inside the cells. Low insulin levels in the blood have the opposite effect by promoting widespread catabolism, especially of reserve body fat.
Insulin resistance (IR) is considered as a pathological condition in which cells fail to respond normally to the hormone insulin. To prevent hyperglycemia and noticeable organ damage over time, the body produces insulin when glucose starts to be released into the bloodstream, primarily from the digestion of carbohydrates in the diet. Under normal conditions of insulin reactivity, this insulin response triggers glucose being taken into body cells, to be used for energy, and inhibits the body from using fat for energy, thereby causing the concentration of glucose in the blood to decrease as a result, staying within the normal range even when a large amount of carbohydrates is consumed. Carbohydrates comprise simple sugars, i.e. monosaccharides, such as glucose and fructose, disaccharides, such as cane sugar, and polysaccharides, e.g. starches. Fructose, which is metabolised into triglycerides in the liver, stimulates insulin production through another mechanism, and can have a more potent effect than other carbohydrates. A habitually high intake of carbohydrates, and particularly fructose, e.g. with sweetened beverages, contributes to insulin resistance and has been linked to weight gain and obesity. If excess blood sugar is not sufficiently absorbed by cells even in the presence of insulin, the increase in the level of blood sugar can result in the classic hyperglycemic triad of polyphagia, polydipsia, and polyuria. Avoiding carbohydrates and sugars, a no-carbohydrate diet or fasting can reverse insulin resistance.
The following is a glossary of diabetes which explains terms connected with diabetes.
Wolfram syndrome, also called DIDMOAD, is a rare autosomal-recessive genetic disorder that causes childhood-onset diabetes mellitus, optic atrophy, and deafness as well as various other possible disorders.
"Maturity onset diabetes of the young" (MODY) refers to any of several hereditary forms of diabetes mellitus caused by mutations in an autosomal dominant gene disrupting insulin production. MODY is often referred to as "monogenic diabetes" to distinguish it from the more common types of diabetes, which involve more complex combinations of causes involving multiple genes and environmental factors. MODY 2 and MODY 3 are the most common forms. MODY should not be confused with latent autoimmune diabetes of adults (LADA) — a form of type 1 DM, with slower progression to insulin dependence than child-onset type 1 DM, and which occurs later in life.
Diabetes mellitus type 1, also known as type 1 diabetes, is a form of diabetes mellitus in which very little or no insulin is produced by the pancreas. Before treatment this results in high blood sugar levels in the body. The classic symptoms are frequent urination, increased thirst, increased hunger, and weight loss. Additional symptoms may include blurry vision, feeling tired, and poor wound healing. Symptoms typically develop over a short period of time.
Latent autoimmune diabetes in adults (LADA) is a form of diabetes mellitus type 1 that occurs in adulthood, often with a slower course of onset than type 1 diabetes diagnosed in juveniles. Adults with LADA may initially be diagnosed incorrectly as having type 2 diabetes based on their age, particularly if they have risk factors for type 2 diabetes such as a strong family history or obesity.
Kir6.2 is a major subunit of the ATP-sensitive K+ channel, an inward-rectifier potassium ion channel. The gene encoding the channel is called KCNJ11 and mutations in this gene are associated with congenital hyperinsulinism.
Calpain-10 is a protein that in humans is encoded by the CAPN10 gene.
PDX1, also known as insulin promoter factor 1, is a transcription factor in the ParaHox gene cluster. In vertebrates, Pdx1 is necessary for pancreatic development, including β-cell maturation, and duodenal differentiation. In humans this protein is encoded by the PDX1 gene, which was formerly known as IPF1. The gene was originally identified in the clawed frog Xenopus laevis and is present in many species across the bilaterian phylogeny. In particular, PDX1 orthologs have been identified in most mammals.
ATP-binding cassette transporter sub-family C member 8 is a protein that in humans is encoded by the ABCC8 gene. ABCC8 orthologs have been identified in all mammals for which complete genome data are available.
Receptor-type tyrosine-protein phosphatase-like N is an enzyme that in humans is encoded by the PTPRN gene.
Receptor-type tyrosine-protein phosphatase N2 (R-PTP-N2) also known as islet cell autoantigen-related protein (ICAAR) and phogrin is an enzyme that in humans is encoded by the PTPRN2 gene. PTPRN and PTPRN2 are both found to be major autoantigens associated with insulin-dependent diabetes mellitus.
Complement C4-A is a protein that in humans is encoded by the C4A gene.
A newly identified and potentially treatable form of monogenic diabetes is the neonatal diabetes caused by activating mutations of the KCNJ11 gene, which codes for the Kir6.2 subunit of the beta cell KATP channel. This disease is considered to be a type of maturity onset diabetes of the young (MODY).
Neonatal diabetes mellitus (NDM) is a disease that affects an infant and their body's ability to produce or use insulin. NDM is a monogenic form of diabetes that occurs in the first 6 months of life. Infants do not produce enough insulin, leading to an increase in glucose accumulation. It is a rare disease, occurring in only one in 100,000 to 500,000 live births. NDM can be mistaken for the much more common type 1 diabetes, but type 1 diabetes usually occurs later than the first 6 months of life. There are two types of NDM: permanent neonatal diabetes mellitus (PNDM) is a lifelong condition. Transient neonatal diabetes mellitus (TNDM) is diabetes that disappears during the infant stage but may reappear later in life.
Diabetes mellitus is a disease in which the beta cells of the endocrine pancreas either stop producing insulin or can no longer produce it in enough quantity for the body's needs. The condition is commonly divided into two types, depending on the origin of the condition: Type 1 diabetes, sometimes called "juvenile diabetes", is caused by destruction of the beta cells of the pancreas. The condition is also referred to as insulin-dependent diabetes, meaning exogenous insulin injections must replace the insulin the pancreas is no longer capable of producing for the body's needs. Dogs can have insulin-dependent, or Type 1, diabetes; research finds no Type 2 diabetes in dogs. Because of this, there is no possibility the permanently damaged pancreatic beta cells could re-activate to engender a remission as may be possible with some feline diabetes cases, where the primary type of diabetes is Type 2. There is another less common form of diabetes, diabetes insipidus, which is a condition of insufficient antidiuretic hormone or resistance to it.
Diabetes mellitus (DM), commonly known as diabetes, is a group of metabolic disorders characterized by high blood sugar levels over a prolonged period. Symptoms of high blood sugar include frequent urination, increased thirst, and increased hunger. If left untreated, diabetes can cause many complications. Acute complications can include diabetic ketoacidosis, hyperosmolar hyperglycemic state, or death. Serious long-term complications include cardiovascular disease, stroke, chronic kidney disease, foot ulcers, and damage to the eyes.
Insulin-dependent diabetes mellitus (IDDM) is a genetic heterogenouse autoimmune disorder, which is triggered by genetic predisposition and environmental factors. The prevalence of insulin-dependent diabetes mellitus (IDDM) among children and young adult from Europe is approximately 0.4%. Insulin-dependent diabetes mellitus (IDDM) is characterized by acute onset and insulin deficiency. Patients with insulin-dependent diabetes mellitus (IDDM) are found with gradual loss of the pancreatic islet beta cells and therefore not able to produce insulin. As a result, they usually need exogenous insulin to maintain their life.
Non insulin dependent diabetes mellitus 1 is a protein that in humans is encoded by the NIDDM1 gene.
