Physiologic Effects Of Insulin
Stand on a streetcorner and ask people if they know what insulin is, and many will reply, "Doesn't it have something to do with blood sugar?" Indeed, that is correct, but such a response is a bit like saying "Mozart? Wasn't he some kind of a musician?" Insulin is a key player in the control of intermediary metabolism, and the big picture is that it organizes the use of fuels for either storage or oxidation. Through these activities, insulin has profound effects on both carbohydrate and lipid metabolism, and significant influences on protein and mineral metabolism. Consequently, derangements in insulin signalling have widespread and devastating effects on many organs and tissues. The Insulin Receptor and Mechanism of Action Like the receptors for other protein hormones, the receptor for insulin is embedded in the plasma membrane. The insulin receptor is composed of two alpha subunits and two beta subunits linked by disulfide bonds. The alpha chains are entirely extracellular and house insulin binding domains, while the linked beta chains penetrate through the plasma membrane. The insulin receptor is a tyrosine kinase. In other words, it functions as an enzyme that transfers phosphate groups from ATP to tyrosine residues on intracellular target proteins. Binding of insulin to the alpha subunits causes the beta subunits to phosphorylate themselves (autophosphorylation), thus activating the catalytic activity of the receptor. The activated receptor then phosphorylates a number of intracellular proteins, which in turn alters their activity, thereby generating a biological response. Several intracellular proteins have been identified as phosphorylation substrates for the insulin receptor, the best-studied of which is insulin receptor substrate 1 or IRS-1. When IRS-1 is activa Continue reading >>
Diabetes Treatment: Using Insulin To Manage Blood Sugar
Understanding how insulin affects your blood sugar can help you better manage your condition. Insulin therapy is often an important part of diabetes treatment. Understand the key role insulin plays in managing your blood sugar, and the goals of insulin therapy. What you learn can help you prevent diabetes complications. The role of insulin in the body It may be easier to understand the importance of insulin therapy if you understand how insulin normally works in the body and what happens when you have diabetes. Regulate sugar in your bloodstream. The main job of insulin is to keep the level of glucose in the bloodstream within a normal range. After you eat, carbohydrates break down into glucose, a sugar that serves as a primary source of energy, and enters the bloodstream. Normally, the pancreas responds by producing insulin, which allows glucose to enter the tissues. Storage of excess glucose for energy. After you eat — when insulin levels are high — excess glucose is stored in the liver in the form of glycogen. Between meals — when insulin levels are low — the liver releases glycogen into the bloodstream in the form of glucose. This keeps blood sugar levels within a narrow range. If your pancreas secretes little or no insulin (type 1 diabetes), or your body doesn't produce enough insulin or has become resistant to insulin's action (type 2 diabetes), the level of glucose in your bloodstream increases because it's unable to enter cells. Left untreated, high blood glucose can lead to complications such as blindness, nerve damage (neuropathy) and kidney damage. The goals of insulin therapy If you have type 1 diabetes, insulin therapy replaces the insulin your body is unable to produce. Insulin therapy is sometimes needed for type 2 diabetes and gestational diabete Continue reading >>
The Role Insulin Plays In The Body
Insulin plays a key role in metabolic functions in the body. People with diabetes have an intimate knowledge of insulin, particularly if they do not produce enough naturally. However, the rest of the public may be less knowledgeable about the role of insulin and its impact on overall health. Insulin is produced in the pancreas of the human body. Its most important function is the way it interacts with glucose (blood sugar) to allow the cells of the body to use that glucose as energy. Insulin can be viewed as a type of key that unlocks the cells and enables glucose to enter. The pancreas senses when there is a spike in glucose in the bloodstream and reacts by producing insulin. According to the Hormone Health Network, insulin also works to ensure the liver stores excess glucose so that it is not actively in the blood. Stored glucose is called glycogen. This glycogen can be converted into fat when it is needed. Insulin also affects other metabolic processes, such as the breakdown of protein or fat. If insulin is not being produced in the right amounts, the result is high blood sugar, or hyperglycemia. Chronic hyperglycemia is the hallmark of diabetes mellitus. Complications of high blood sugar include damage to the nervous system, kidneys, eyes, and the extremities. Type 1 diabetes occurs when the pancreas fails to produce enough insulin. Supplementation with insulin will be necessary to avoid drastic changes in blood glucose levels. When a person has type 2 diabetes, cells fail to respond to insulin properly. This is referred to as insulin resistance. As the disease progresses, a lack of insulin may also develop. Typically with this type of diabetes, excessive body weight and not enough exercise are the culprits in insulin resistance. Eating a healthier diet and becoming Continue reading >>
Insulin And Insulin Resistance
Go to: Abstract As obesity and diabetes reach epidemic proportions in the developed world, the role of insulin resistance and its consequences are gaining prominence. Understanding the role of insulin in wide-ranging physiological processes and the influences on its synthesis and secretion, alongside its actions from the molecular to the whole body level, has significant implications for much chronic disease seen in Westernised populations today. This review provides an overview of insulin, its history, structure, synthesis, secretion, actions and interactions followed by a discussion of insulin resistance and its associated clinical manifestations. Specific areas of focus include the actions of insulin and manifestations of insulin resistance in specific organs and tissues, physiological, environmental and pharmacological influences on insulin action and insulin resistance as well as clinical syndromes associated with insulin resistance. Clinical and functional measures of insulin resistance are also covered. Despite our incomplete understanding of the compl Continue reading >>
What Does Insulin Do In My Body?
Diabetes mellitus (MEL-ih-tus), often referred to as diabetes, is characterized by high blood glucose (sugar) levels that result from the body’s inability to produce enough insulin and/or effectively utilize the insulin. Diabetes is a serious, life-long condition and the sixth leading cause of death in the United States. Diabetes is a disorder of metabolism (the body's way of digesting food and converting it into energy). There are three forms of diabetes. Type 1 diabetes is an autoimmune disease that accounts for five- to 10-percent of all diagnosed cases of diabetes. Type 2 diabetes may account for 90- to 95-percent of all diagnosed cases. The third type of diabetes occurs in pregnancy and is referred to as gestational diabetes. Left untreated, gestational diabetes can cause health issues for pregnant women and their babies. People with diabetes can take preventive steps to control this disease and decrease the risk of further complications. Continue reading >>
How Insulin And Glucagon Work
Insulin and glucagon are hormones that help regulate the levels of blood glucose, or sugar, in your body. Glucose, which comes from the food you eat, moves through your bloodstream to help fuel your body. Insulin and glucagon work together to balance your blood sugar levels, keeping them in the narrow range that your body requires. These hormones are like the yin and yang of blood glucose maintenance. Read on to learn more about how they function and what can happen when they don’t work well. Insulin and glucagon work in what’s called a negative feedback loop. During this process, one event triggers another, which triggers another, and so on, to keep your blood sugar levels balanced. How insulin works During digestion, foods that contain carbohydrates are converted into glucose. Most of this glucose is sent into your bloodstream, causing a rise in blood glucose levels. This increase in blood glucose signals your pancreas to produce insulin. The insulin tells cells throughout your body to take in glucose from your bloodstream. As the glucose moves into your cells, your blood glucose levels go down. Some cells use the glucose as energy. Other cells, such as in your liver and muscles, store any excess glucose as a substance called glycogen. Your body uses glycogen for fuel between meals. Read more: Simple vs. complex carbs » How glucagon works Glucagon works to counterbalance the actions of insulin. About four to six hours after you eat, the glucose levels in your blood decrease, triggering your pancreas to produce glucagon. This hormone signals your liver and muscle cells to change the stored glycogen back into glucose. These cells then release the glucose into your bloodstream so your other cells can use it for energy. This whole feedback loop with insulin and gluca Continue reading >>
- How insulin and glucagon work to regulate blood sugar levels
- Insulin, glucagon and somatostatin stores in the pancreas of subjects with type-2 diabetes and their lean and obese non-diabetic controls
- Effects of Insulin Plus Glucagon-Like Peptide-1 Receptor Agonists (GLP-1RAs) in Treating Type 1 Diabetes Mellitus: A Systematic Review and Meta-Analysis
How Insulin Works
Insulin is a hormone made by one of the body's organs called the pancreas. Insulin helps your body turn blood sugar (glucose) into energy. It also helps your body store it in your muscles, fat cells, and liver to use later, when your body needs it. After you eat, your blood sugar (glucose) rises. This rise in glucose triggers your pancreas to release insulin into the bloodstream. Insulin travels through the blood to your body's cells. It tells the cells to open up and let the glucose in. Once inside, the cells convert glucose into energy or store it to use later. Without insulin, your body can't use or store glucose for energy. Instead, the glucose stays in your blood. Continue reading >>
This article is about the insulin protein. For uses of insulin in treating diabetes, see insulin (medication). Not to be confused with Inulin. Insulin (from Latin insula, island) is a peptide hormone produced by beta cells of the pancreatic islets, and 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, especially, glucose from the blood into fat, liver 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. Beta cells are sensitive to glucose concentrations, also known as blood sugar levels. When the glucose level is high, the beta cells secrete insulin into the blood; when glucose levels are low, secretion of insulin is inhibited. Their neighboring alpha cells, by taking their cues from the beta cells, secrete glucagon into the blood in the opposite manner: increased secretion when blood glucose is low, and decreased secretion when glucose concentrations are high. Glucagon, through stimulating the liver to release glucose by glycogenolysis and gluconeogenesis, has the opposite effect of insulin. The secretion of insulin and glucagon into the Continue reading >>
Insulin's Role In The Human Body
Insulin is a hormone produced by the pancreas that has a number of important functions in the human body, particularly in the control of blood glucose levels and preventing hyperglycemia. It also has an effect on several other areas of the body, including the synthesis of lipids and regulation of enzymatic activity. Insulin and Metabolic Processes The most important role of insulin in the human body is its interaction with glucose to allow the cells of the body to use glucose as energy. The pancreas usually produces more insulin in response to a spike in blood sugar level, for example after eating a meal high in energy. This is because the insulin acts as a “key” to open up the cells in the body and allows the glucose to be used as an energy source. Additionally, when there is excess glucose in the bloodstream, known as hyperglycemia, insulin encourages the storage of glucose as glycogen in the liver, muscle and fat cells. These stores can then be used at a later date when energy requirements are higher. As a result of this, there is less insulin in the bloodstream, and normal blood glucose levels are restored. Insulin stimulates the synthesis of glycogen in the liver, but when the liver is saturated with glycogen, an alternative pathway takes over. This involves the uptake of additional glucose into adipose tissue, leading to the synthesis of lipoproteins. Results Without Insulin In the absence of insulin, the body is not able to utilize the glucose as energy in the cells. As a result, the glucose remains in the bloodstream and can lead to high blood sugar, known as hyperglycemia. Chronic hyperglycemia is characteristic of diabetes mellitus and, if untreated, is associated with severe complications, such as damage to the nervous system, eyes, kidneys and extremitie Continue reading >>
You And Your Hormones
What is insulin? Insulin is a hormone made by an organ located behind the stomach called the pancreas. Here, insulin is released into the bloodstream by specialised cells called beta cells found in areas of the pancreas called islets of langerhans (the term insulin comes from the Latin insula meaning island). Insulin can also be given as a medicine for patients with diabetes because they do not make enough of their own. It is usually given in the form of an injection. Insulin is released from the pancreas into the bloodstream. It is a hormone essential for us to live and has many effects on the whole body, mainly in controlling how the body uses carbohydrate and fat found in food. Insulin allows cells in the muscles, liver and fat (adipose tissue) to take up sugar (glucose) that has been absorbed into the bloodstream from food. This provides energy to the cells. This glucose can also be converted into fat to provide energy when glucose levels are too low. In addition, insulin has several other metabolic effects (such as stopping the breakdown of protein and fat). How is insulin controlled? When we eat food, glucose is absorbed from our gut into the bloodstream. This rise in blood glucose causes insulin to be released from the pancreas. Proteins in food and other hormones produced by the gut in response to food also stimulate insulin release. However, once the blood glucose levels return to normal, insulin release slows down. In addition, hormones released in times of acute stress, such as adrenaline, stop the release of insulin, leading to higher blood glucose levels. The release of insulin is tightly regulated in healthy people in order to balance food intake and the metabolic needs of the body. Insulin works in tandem with glucagon, another hormone produced by the pan Continue reading >>
What Is Insulin?
Essential for life, the hormone insulin regulates many metabolic processes that provide cells with needed energy. Understanding insulin, what insulin does, and how it affects the body, is important to your overall health. Tucked away behind the stomach is an organ called the pancreas, which produces insulin. Insulin production is regulated based on blood sugar levels and other hormones in the body. In a healthy individual, insulin production and release is a tightly regulated process, allowing the body to balance its metabolic needs. What does insulin do? Insulin allows the cells in the muscles, fat and liver to absorb glucose that is in the blood. The glucose serves as energy to these cells, or it can be converted into fat when needed. Insulin also affects other metabolic processes, such as the breakdown of fat or protein. Problems with insulin production or use The most common problem associated with insulin is diabetes. Diabetes occurs when the body either does not secrete enough insulin or when the body no longer uses the insulin it secretes effectively. Diabetes falls into two categories: Type 1 diabetes occurs when the pancreas cannot produce insulin sufficiently to meet its own needs. This commonly occurs in children, and while an exact cause has not been found, many consider it to be an autoimmune disease. Some symptoms of type 1 diabetes include tiredness, increased urination and thirst, and problems with vision. Type 2 diabetes is more commonly associated with adults and lifestyle choices. People with type 2 diabetes will produce insulin but often not enough for their body's needs. They may also struggle to use the insulin they produce effectively. Patients may not know they have type 2 diabetes until they have an annual checkup, as symptoms tend to be mild un Continue reading >>
The Role Of Insulin In The Body
Tweet Insulin is a hormone which plays a key role in the regulation of blood glucose levels. A lack of insulin, or an inability to adequately respond to insulin, can each lead to the development of the symptoms of diabetes. In addition to its role in controlling blood sugar levels, insulin is also involved in the storage of fat. Insulin is a hormone which plays a number of roles in the body’s metabolism. Insulin regulates how the body uses and stores glucose and fat. Many of the body’s cells rely on insulin to take glucose from the blood for energy. Insulin and blood glucose levels Insulin helps control blood glucose levels by signaling the liver and muscle and fat cells to take in glucose from the blood. Insulin therefore helps cells to take in glucose to be used for energy. If the body has sufficient energy, insulin signals the liver to take up glucose and store it as glycogen. The liver can store up to around 5% of its mass as glycogen. Some cells in the body can take glucose from the blood without insulin, but most cells do require insulin to be present. Insulin and type 1 diabetes In type 1 diabetes, the body produces insufficient insulin to regulate blood glucose levels. Without the presence of insulin, many of the body’s cells cannot take glucose from the blood and therefore the body uses other sources of energy. Ketones are produced by the liver as an alternative source of energy, however, high levels of the ketones can lead to a dangerous condition called ketoacidosis. People with type 1 diabetes will need to inject insulin to compensate for their body’s lack of insulin. Insulin and type 2 diabetes Type 2 diabetes is characterised by the body not responding effectively to insulin. This is termed insulin resistance. As a result the body is less able to t Continue reading >>
What Is Insulin?
Insulin is a hormone made by the pancreas that allows your body to use sugar (glucose) from carbohydrates in the food that you eat for energy or to store glucose for future use. Insulin helps keeps your blood sugar level from getting too high (hyperglycemia) or too low (hypoglycemia). The cells in your body need sugar for energy. However, sugar cannot go into most of your cells directly. After you eat food and your blood sugar level rises, cells in your pancreas (known as beta cells) are signaled to release insulin into your bloodstream. Insulin then attaches to and signals cells to absorb sugar from the bloodstream. Insulin is often described as a “key,” which unlocks the cell to allow sugar to enter the cell and be used for energy. If you have more sugar in your body than it needs, insulin helps store the sugar in your liver and releases it when your blood sugar level is low or if you need more sugar, such as in between meals or during physical activity. Therefore, insulin helps balance out blood sugar levels and keeps them in a normal range. As blood sugar levels rise, the pancreas secretes more insulin. If your body does not produce enough insulin or your cells are resistant to the effects of insulin, you may develop hyperglycemia (high blood sugar), which can cause long-term complications if the blood sugar levels stay elevated for long periods of time. Insulin Treatment for Diabetes People with type 1 diabetes cannot make insulin because the beta cells in their pancreas are damaged or destroyed. Therefore, these people will need insulin injections to allow their body to process glucose and avoid complications from hyperglycemia. People with type 2 diabetes do not respond well or are resistant to insulin. They may need insulin shots to help them better process Continue reading >>
Role Of Insulin And Other Hormones In Diabetes
SHARE RATE★★★★★ Insulin and glucose Our bodies require energy to function properly and we get that energy from three food groups: protein, fat, and carbohydrates (sugars, starches, and fibers). When the body digests carbohydrates, they are transformed through digestion into a very important source of instant energy, a form of sugar called glucose.1,2 Three forms of simple sugars (also called monosaccharides) are able to enter the bloodstream directly after digestion. These are often broken down from more complex sugars (polysaccharides and disaccharides). These simple sugars include glucose (found in most carbohydrates, including grains and starches), fructose (found in fruits and vegetables), and galactose (found in dairy products and in certain vegetables). The word glucose comes from the Greek word for sweet, and it is the key source of energy for cells in the body. Upon digestion, glucose can be used for instant energy or stored in the form of glycogen when the body’s energy needs are being met.1,2 Hormones and glucose control Our bodies depend on the action of a number of different hormones, working together in conjunction, to control how we use glucose. We depend on insulin, a hormone produced in the beta cells of the pancreas (an organ located behind the stomach) to use glucose. Insulin serves as sort of a “gate keeper,” allowing glucose to enter cells where it can be transformed into energy and used to support vital cell functions. Insulin also has other important functions related to the way our body uses glucose.3,4 In addition to insulin, another hormone produced by beta cells called amylin controls how quickly glucose is released into the blood stream after a meal. It does this by slowing emptying of the stomach and increasing the feeling tha Continue reading >>
What Is Insulin?
Insulin is a hormone; a chemical messenger produced in one part of the body to have an action on another. It is a protein responsible for regulating blood glucose levels as part of metabolism.1 The body manufactures insulin in the pancreas, and the hormone is secreted by its beta cells, primarily in response to glucose.1 The beta cells of the pancreas are perfectly designed "fuel sensors" stimulated by glucose.2 As glucose levels rise in the plasma of the blood, uptake and metabolism by the pancreas beta cells are enhanced, leading to insulin secretion.1 Insulin has two modes of action on the body - an excitatory one and an inhibitory one:3 Insulin stimulates glucose uptake and lipid synthesis It inhibits the breakdown of lipids, proteins and glycogen, and inhibits the glucose pathway (gluconeogenesis) and production of ketone bodies (ketogenesis). What is the pancreas? The pancreas is the organ responsible for controlling sugar levels. It is part of the digestive system and located in the abdomen, behind the stomach and next to the duodenum - the first part of the small intestine.4 The pancreas has two main functional components:4,5 Exocrine cells - cells that release digestive enzymes into the gut via the pancreatic duct The endocrine pancreas - islands of cells known as the islets of Langerhans within the "sea" of exocrine tissue; islets release hormones such as insulin and glucagon into the blood to control blood sugar levels. Islets are highly vascularized (supplied by blood vessels) and specialized to monitor nutrients in the blood.2 The alpha cells of the islets secrete glucagon while the beta cells - the most abundant of the islet cells - release insulin.5 The release of insulin in response to elevated glucose has two phases - a first around 5-10 minutes after g Continue reading >>