Incidence of diabetes is growing rapidly, especially in the US. According to an estimation, 25.8 million people in the US and 347 million people worldwide are afflicted with diabetes. The heterogeneous group of syndromes, characterized by elevated blood glucose level and low blood insulin. According to the American Diabetes Association ADA, there are four clinical classifications of diabetes:
1. Type 1: formerly insulin-dependent diabetes mellitus
2. Type 2: formerly non-insulin-dependent diabetes mellitus
3. Gestational diabetes
4. Diabetes due to genetic defects or medications
Type 1 diabetes most commonly found in children, adolescents, or young adults. The disease is characterized by the deficiency of insulin due to the destruction of beta cells. Loss of beta cell functions results from autoimmune-mediated processes that may be triggered by viruses or other environmental toxins. If beta cells don,t function well, the pancreas fails to respond to glucose. In such a case, the person will show the classic symptoms of insulin deficiency i.e. polydipsia, polyphagia, polyuria and weight loss. This type of diabetes requires exogenous insulin for the treatment of hyperglycemia.
Causes of type 1 diabetes
In a normal postabsorptive time, constant beta-cell secretion maintains low basal levels of circulating insulin. This slows down the lipolysis, proteolysis and glycogenolysis. Insulin is released from beta cells after ingestion of a meal, in response to increases in circulating glucose and amino acids. Without functional beta cells, those people with type 1 diabetes cannot maintain basal secretion of insulin and cannot respond to variations in circulating glucose.
A person with type 1 diabetes require:
1. Exogenous insulin
2. Avoid ketoacidosis
3. Maintain acceptable levels of glycosylated haemoglobin
Type 2 diabetes
This type is found in more than 90% of cases. It is due to genetic factors, ageing, obesity and peripheral insulin resistance. It is not an autoimmune process. Patients with type 2 diabetes typically are not ketotic. Metabolic alteration in type 2 diabetes is milder than those observed in type 1.
Type 2 diabetes is caused by a lack of sensitivity of organs to insulin. In this type of diabetes, pancreas retains beta cell functions but the levels of insulin in the blood is too low to maintain glucose hemostasis. The beta-cell mass gradually declines due to low secretion of insulin in type 2 diabetes. Patients suffering from type 2 diabetes are obese as compared to those having type 1.
The goal of treating diabetes is:
1. To maintain blood glucose within normal limits
2. To prevent long term complications.
Weight loss, exercise, and dietary modification decrease insulin resistance and correct hyperglycemia. Most patients need pharmacological intervention with oral glucose-lowering agents.
It is a condition in which a woman without diabetes has high blood glucose levels during pregnancy.
Symptoms of gestational diabetes mellitus
1. Unusual thirst
2. Frequent urination
4. Frequent vaginal, skin and bladder infections
5. Blurred vision
The cause of gestational diabetes is that the placenta secretes a hormone that leads to a buildup of glucose in the blood.
Insulin injections are the kind of quality medication for gestational diabetes.
Insulin is a polypeptide hormone consisting of two peptide chains that are connected by disulfide bonds. Blood glucose levels regulate the secretion of insulin. Insulin secretion is also regulated by certain amino acids, other hormones and autoimmune mediators. Upon secretion, insulin is taken up by glucose transporter into the beta cells of the pancreas. There, it is phosphorylated by glucokinase, which acts as a glucose sensor. The products of glucose metabolism enter the mitochondrial respiratory chain and produce ATP. The increase in ATP causes a blockade of potassium channels, leading to membrane depolarization and an influx of calcium. The increase in calcium causes pulsatile insulin exocytosis.
Mechanism of insulin action
Exogenous insulin is administered to replace absent insulin secretion in type 1 and type 2 diabetes mellitus.
Adverse reactions to insulin
2. Weight gain
3. Local injection site reaction
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