Insulin insufficient production

Insulin is a peptide hormone, secreted by the pancreas, that regulates glucose metabolism in the body. Insufficient production of insulin or failure of insulin to stimulate target sites in liver, muscle, and adipose tissue leads to the serious metabolic disorder known as diabetes mellitus. Diabetes afflicts millions of people worldwide. Diabetic individuals typically exhibit high levels of glucose in the blood, but insulin injection therapy allows diabetic individuals to maintain normal levels of blood glucose. 

Diabetes mellitus is a complicated, chronic disorder characterized by either insufficient insulin production by the beta cells of die pancreas or by cellular resistance to insulin. Insulin insufficiency results in elevated blood glucose levels, or hyperglycemia As a result of the disease, individuals with diabetes are at greater risk for a number of disorders, including myocardial infarction, cerebrovascular accident (stroke), blindness, kidney disease, and lower limb amputations. 

Gene Therapy Insufficient production of insulin in the body is often caused by deficiencies in the genes of the patient. If these genes could be replaced, the sickness could be cured. The technique is being tried out in the lab, but so far with little success. 

Diet probably plays a secondary role to the primary metabolic aberration, insulin production. Impairment within the monkey to secrete adequate, functional quantities of insulin undoubtedly lies at the root of most of its inability to adequately control glucose and to maintain normal concentrations of lipids in the blood. Metabolic abnormalities arise because of decreasing reservoirs of insulin secretory capacity in the beta cells. Thus, in the Macaca nigra, there is a direct link between their inability to handle the carbohydrate in their diet, which stems from insulin insufficiency, and the manifestations of the diabetic syndrome which create enough metabolic abberrations to cause increased aortic atherosclerosis. 

Those with type 1 diabetes mellitus produce insulin in insufficient amounts and tiierefore must have insulin supplementation to survive Type 1 diabetes usually has a rapid onset, occurs before die age of 20 years, produces more severe symptoms tiian type 2 diabetes, and is more difficult to control. Major symptoms of type 1 diabetes include hyperglycemia, polydipsia (increased thirst), polyphagia (increased appetite), polyuria (increased urination), and weight loss. Treatment of type 1 diabetes is particularly difficult to control because of the lack of insulin production by die pancreas. Treatment requires a strict regimen tiiat typically includes a carefully calculated diet, planned physical activity, home glucose testing several times a day, and multiple daily insulin injections. 

Acute steatosis of the liver may have explained this presentation. In insulin overdose, the combination of greatly increased hepatic production of triglycerides from glucose and reduced production of apolipoprotein B 100 results in an insufficient increase in the transport of triglycerides in VLDL particles from liver to muscle and adipose tissue and contributes to the steatosis. 

Diabetes mellitus is a disease caused by insufficient insulin secretion or a decrease in the peripheral effects of insulin. This disease is characterized by a primary defect in the metabolism of carbohydrates and other energy substrates. These metabolic defects can lead to serious acute and chronic pathologic changes. The term diabetes mellitus differentiates this disease from an unrelated disorder known as diabetes insipidus. Diabetes insipidus is caused by a lack of antidiuretic hormone (ADH) production or insensitivity to ADH. Consequently, the full terminology of diabetes mellitus should be used when referring to the insulin-related disease. Most clinicians, however, refer to diabetes mellitus as simply diabetes. ... 

Insulin, among other things, also stimulates production of lipoprotein lipase (LPL). With insulin deficiency in diabetes, there is insufficient LPL to release fatty acids from the triglycerides of VLDL and chylomicrons (see Fig. 6.4), another reason for accumulating serum triglycerides, apart from increased VLDL production by the liver. 

Because carbohydrate utilization is impaired, a lack of insulin leads to the uncontrolled breakdown of lipids and proteins. Large amounts of acetyl CoA are then produced by P-oxidation. However, much of the acetyl CoA cannot enter the citric acid cycle, because there is insufficient oxaloacetate for the condensation step. Recall that mammals can synthesize oxaloacetate from pyruvate, a product of glycolysis, but not from acetyl CoA instead, they generate ketone bodies. A striking feature of diabetes is the shift in fuel usage from carbohydrates to fats glucose, more abundant than ever, is spurned. In high concentrations, ketone bodies overwhelm the kidney s capacity to maintain acid-base balance. The untreated diabetic can go into a coma because of a lowered blood pH level and dehydration. 

Type II diabetes mellitus Type II diabetes mellitus (age-onset diabetes) is when the pancreas ability to produced insulin is either diminished (age) or is insufficient to metabolize the excess serum glucose (overweight, lack of exercise). Insulin is produced but is not effective. The patient controls Type II diabetes mellitus by diet, exercise, and oral diabetes medication that stimulate insulin production in the pancreas and other organs. This is referred to as non-insulin-dependent diabetes (NIDDM). 

The term diabetes from the Greek dia, through, and bainen, to go, means passing through or siphon and describes the excessive production of urine (polyuria) in this condition. Diabetes mellitus mellitus, honey) refers to the sweet taste of the urine, while in diabetes insipidus the urine is insipid (i.e. tasteless). (Don t worry, you don t have to taste the urine nowadays ) Diabetes is caused by lack of insulin activity while diabetes insipidus is caused by insufficient vasopressin (antidiuretic hormone) activity. 

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