Carbohydrates, Proteins, Fats, And Blood Sugar
The body uses three main nutrients to function-carbohydrate, protein, and fat. These nutrients are digested into simpler compounds. Carbohydrates are used for energy (glucose). Fats are used for energy after they are broken into fatty acids. Protein can also be used for energy, but the first job is to help with making hormones, muscle, and other proteins. Nutrients needed by the body and what they are used for Type of nutrient Where it is found How it is used Carbohydrate (starches and sugars) Breads Grains Fruits Vegetables Milk and yogurt Foods with sugar Broken down into glucose, used to supply energy to cells. Extra is stored in the liver. Protein Meat Seafood Legumes Nuts and seeds Eggs Milk products Vegetables Broken down into amino acids, used to build muscle and to make other proteins that are essential for the body to function. ADVERTISINGinRead invented by Teads Fat Oils Butter Egg yolks Animal products Broken down into fatty acids to make cell linings and hormones. Extra is stored in fat cells. After a meal, the blood sugar (glucose) level rises as carbohydrate is digested. This signals the beta cells of the pancreas to release insulin into the bloodstream. Insulin helps glucose enter the body's cells to be used for energy. If all the glucose is not needed for energy, some of it is stored in fat cells and in the liver as glycogen. As sugar moves from the blood to the cells, the blood glucose level returns to a normal between-meal range. Several hormones and processes help regulate the blood sugar level and keep it within a certain range (70 mg/dL to 120 mg/dL). When the blood sugar level falls below that range, which may happen between meals, the body has at least three ways of reacting: Cells in the pancreas can release glucagon, a hormone that signals the b Continue reading >>
Metabolism, Insulin And Other Hormones
Metabolism literally means transformation but has become a general term that encompasses all chemical processes that occur in the living body; processes that are the essence of life. These include processes that build up tissues (anabolism) and that make tissues function, which generally cost energy, and processes that degrade tissues (catabolism), which generally produce energy. However, a full description of everything that goes on in the body is beyond our scope: in this section we will focus on the normal physiology of processes that are related to the handling of nutrients (sugars, proteins and fat) and their regulation, with particular attention for the processes that become disturbed in diabetes. These processes of glucose metabolism, lipid metabolism, ketone body metabolism, protein metabolism and amino acid metabolism are controlled by a set of glucoregulatory hormones such as insulin, glucagon , amylin, the incretins (GLP-1, glucose-dependent insulinotropic peptide (GIP)), several adipokines (leptin, adiponectin, acylation stimulating protein and resistin), epinephrine, cortisol, and growth hormone. Of these, insulin and amylin are derived from the β-cells of the pancreas, glucagon from the α-cells of the pancreas, GLP-1 and GIP from the L-cells of the intestine and the adipokines from adipose tissue[1][2][3]. What is Metabolism? Metabolism refers to the pathways of biochemical processes (metabolic pathways) that occur in all living organisms to maintain life[4][5][6]. These biochemical processes allow us to grow, reproduce, repair damage, and respond to our environment. Throughout its lifetime the body undergoes cycles of building and degradation, taking up fuel and building blocks in the form of food, ultimately to lose them as water, carbon dioxide, urea Continue reading >>
Insulin
Insulin is a hormone secreted by the beta cells of pancreas, and is important in the regulation of carbohydrate and fat metabolism in the body. Marie Boran Discovery: The discovery of Insulin by Banting and Best in 1922 was a major breakthrough in endocrinology. Chemistry: Insulin is made up of 2 polypeptide chains linked by disulphide linkages. Synthesis: Insulin is synthesized as preprohormone having molecular weight of 11500. It is converted into proinsulin in endoplasmic reticulum with molecular weight of 9000, and finally into insulin in Golgi apparatus having molecular weight of 5808. Metabolism Insulin has a plasma half life of 6 minutes before being broken down catalyzed by the enzyme Insulinase. Insulin receptor Insulin receptor is made up of 4 subunits which are linked through disulphide linkages. There are 2 alpha and 2 beta subunits. The 2 alpha subunits are located outside cell membrane and have the insulin binding site. The 2 beta subunits penetrate cell membrane. Mechanism of Action of Insulin Mechanism of action can be well understood considering the following points: 1. Binding of insulin with alpha subunit 2. Autophosphorylation of alpha subunit 3. Activation of tyrosine kinase 4. Phosphorylation of intracellular enzymes Metabolic effects The metabolic effects of insulin include: 1. Glucose uptake (glucose transport proteins) 2. Amino acid, potassium & phosphate uptake 3. Phosphorylation of enzymes (10-15 min) 4. DNA transcription & RNA translation (hours-days) Effects of Insulin: Insulin affects the following: 1. Carbohydrate metabolism Insulin has profound effects on the following: a. Skeletal muscles: Insulin promotes glucose uptake and metabolism by the skeletal muscles. The muscles use fats in the resting state of the body as the membranes are imp Continue reading >>
Insulin Effects In Muscle And Adipose Tissue.
Abstract The major effects of insulin on muscle and adipose tissue are: (1) Carbohydrate metabolism: (a) it increases the rate of glucose transport across the cell membrane, (b) it increases the rate of glycolysis by increasing hexokinase and 6-phosphofructokinase activity, (c) it stimulates the rate of glycogen synthesis and decreases the rate of glycogen breakdown. (2) Lipid metabolism: (a) it decreases the rate of lipolysis in adipose tissue and hence lowers the plasma fatty acid level, (b) it stimulates fatty acid and triacylglycerol synthesis in tissues, (c) it increases the uptake of triglycerides from the blood into adipose tissue and muscle, (d) it decreases the rate of fatty acid oxidation in muscle and liver. (3) Protein metabolism: (a) it increases the rate of transport of some amino acids into tissues, (b) it increases the rate of protein synthesis in muscle, adipose tissue, liver, and other tissues, (c) it decreases the rate of protein degradation in muscle (and perhaps other tissues). These insulin effects serve to encourage the synthesis of carbohydrate, fat and protein, therefore, insulin can be considered to be an anabolic hormone. Continue reading >>
Lipid Metabolism - An Overview | Sciencedirect Topics
Isabelle Coppens, ... Stanislas Tomavo, in Toxoplasma Gondii (Second Edition) , 2014 Fatty Acid Biosynthetic Pathways Generalities 270 Phospholipid Biosynthetic Pathways Generalities 274 Phospholipid Composition and Physiological Relevance in Toxoplasma 274 Glycerolipid Biosynthetic Pathways Generalities 277 Sterol Lipid Biosynthetic Pathways Generalities 278 Sterol Salvage and Transport in Toxoplasma 279 Sphingolipid Biosynthetic Pathways Generalities 280 Isoprenoid Biosynthetic Pathways Generalities 282 Deborah S. Greco, in Nutritional and Therapeutic Interventions for Diabetes and Metabolic Syndrome , 2012 Ketoacidotic, Hyperosmolar or Complicated Diabetes Mellitus: Pathophysiology and Clinical Signs Lipid metabolism in the liver becomes deranged with insulin deficiency and non-esterified fatty acids are converted to acetyl-CoA rather than being incorporated into triglycerides. Acetyl-CoA accumulates in the liver and is converted into acetoacetyl-CoA and then ultimately to acetoacetic acid. Finally, the liver starts to generate large amounts of ketones including acetoacetic acid, beta-hydroxybutyrate and acetone. As insulin deficiency culminates in DKA, accumulation of ketones and lactic acid in the blood and loss of electrolytes and water in the urine results in profound dehydration, hypovolemia, metabolic acidosis, and shock. Ketonuria and osmotic diuresis caused by glycosuria result in urinary sodium and potassium loss which exacerbates hypovolemia and dehydration. Nausea, anorexia and vomiting, caused by stimulation of the chemoreceptor trigger zone via ketonemia and hyperglycemia, contribute to the dehydration caused by osmotic diuresis. Dehydration and shock lead to prerenal azotemia and a decline in glomerular filtration rate (GFR). Declining GFR leads to fur Continue reading >>
- Effect of Probiotics on Glucose and Lipid Metabolism in Type 2 Diabetes Mellitus: A Meta-Analysis of 12 Randomized Controlled Trials
- Impact of menopause and diabetes on atherogenic lipid profile: is it worth to analyse lipoprotein subfractions to assess cardiovascular risk in women?
- Exercise and Glucose Metabolism in Persons with Diabetes Mellitus: Perspectives on the Role for Continuous Glucose Monitoring
Metabolic Effects Of Insulin
1. Metabolic Effects of Insulin on Cellular Uptake of Glucose Supachai A. Basit, RMT, PhD 2. Overview • Four major organs play a dominant role in fuel metabolism • Integration of energy metabolism is controlled primarily by the actions of insulin and glucagon 3. Insulin • Polypeptide hormone produce by the beta cells of the islet of Langerhans of the pancreas • Most important hormone coordinating the use of fuels by tissues • Metabolic effects anabolic – Favoring the synthesis of glycogen, triacylglycerols and protein 4. Structure of Insulin • 51 amino acids • Polypeptide A and B, linked together by a disulfide bridges • Intramolecular disulfide bridge between amino acid residues of the A chain 5. Synthesis of Insulin • Two inactive precursors cleaved to form the active hormone plus the C-peptide • C-peptide essential for proper insulin folding 6. Stimulation of Insulin Secretion • Insulin and glucagon secretion is closely coordinated at the islet of Langerhans • Secretion is regulated so that the rate of hepatic glucose production is kept equal to the use of glucose by peripheral tissues 7. Stimulation of Insulin Secretion is Increased by: Glucose • ß cells contain Glut-2 transporters and have glucokinase activity and thus can phosphorylate glucose in amounts proportional to its actual concentration in blood • Ingestion of CHO rich meal leads to a rise in blood glucose, which is a signal for insulin secretion and decrease glucagon synthesis and release 8. Stimulation of Insulin Secretion is Increased by: Amino Acids • Ingestion of protein causes a transient rise in plasma amino acids level, which in turn induces the secretion of insulin • Elevated plasma arginine stimulates insulin secretion 9. Stimulation of Insulin Secre Continue reading >>
How Do Fats & Proteins Affect Blood Sugar Levels?
After you eat, your blood sugar levels increase and trigger the release of insulin, an important hormone in managing how your body uses glucose. Different types of nutrients affect blood sugar differently, and maintaining an appropriate intake of carbohydrates, proteins and fats will help control blood sugar levels and prevent or manage metabolic diseases like Type 2 diabetes. Carbohydrates, proteins and fats are the three macronutrients your body needs. Carbohydrates are primarily used for energy, while proteins are important for rebuilding tissue, and fats are important for maintaining cell membranes and facilitating vitamin absorption, among other functions. Carbohydrates have the most significant impact on blood sugar, so carbohydrate intake should be monitored closely by individuals with or at risk for Type 2 diabetes. Protein's Effects on Blood Sugar Compared to carbohydrates, protein keeps blood sugar levels steady. When consumed alone, protein does not generate a rise in blood sugar. According to a study published in 2003 in “American Society for Clinical Nutrition,” individuals with Type 2 diabetes who maintained a 30:40:30 intake ratio of protein to carbohydrates to fat showed a 40 percent lower blood sugar response than those who maintained a 15:55:30 intake ratio. This suggests that protein is neutral food for blood sugar levels and can replace at least some carbohydrates to yield a better overall blood sugar response. Fat's Effects on Blood Sugar Like protein, fat has significantly less impact on blood sugar than carbohydrates. When consumed alone, ingested fats have no bearing on the concentration of circulating blood sugar. Replacing some carbohydrate content with healthy dietary fats could therefore result in steadier overall levels of blood sugar. M Continue reading >>
How Insulin Really Works: It Causes Fat Storage…but Doesn’t Make You Fat
Many people believe that insulin is to blame for the obesity epidemic. When you understand how it actually works, you’ll know why this is a lie. Insulin has been taking quite a beating these days. If we’re to listen to some “experts,” it’s an evil hormone whose sole goal is making us fat, type 2 diabetics. Furthermore, we’re told that carbohydrates also are in on the conspiracy. By eating carbs, we open the insulin floodgates and wreak havoc in our bodies. How true are these claims, though? Does it really make sense that our bodies would come with an insidious mechanism to punish carbohydrate intake? Let’s find out. What is Insulin, Anyway? Insulin is a hormone, which means it’s a substance the body produces to affect the functions of organs or tissues, and it’s made and released into the blood by the pancreas. Insulin’s job is a very important one: when you eat food, it’s broken down into basic nutrients (protein breaks down into amino acids; dietary fats into fatty acids; and carbohydrates into glucose), which make their way into the bloodstream. These nutrients must then be moved from the blood into muscle and fat cells for use or storage, and that’s where insulin comes into play: it helps shuttle the nutrients into cells by “telling” the cells to open up and absorb them. So, whenever you eat food, your pancreas releases insulin into the blood. As the nutrients are slowly absorbed into cells, insulin levels drop, until finally all the nutrients are absorbed, and insulin levels then remain steady at a low, “baseline” level. This cycle occurs every time you eat food: amino acids, fatty acids, and/or glucose find their way into your blood, and they’re joined by additional insulin, which ushers them into cells. Once the job is done, insu Continue reading >>
Effect Of Insulin On Protein Synthesis
The mechanism by which insulin controls protein metabolism is not fully understood. Insulin stimulates protein synthesis; it also enhances transport of some amino acids, but the latter action does not appear to be sufficient explanation of the increase in synthesis. The various actions seem to be independent of effects on glucose metabolism. In diabetic muscle there are fewer than normal polysomes, and insulin rapidly enhances attachment of monomers to messenger-RNA. Insulin also increases the effectiveness of cell sap in catalyzing protein synthesis by ribosomal systems. The way in which the hormone may affect either initiation or peptide synthesis is not known. Experiments are reported bearing on whether availability of amino acids could be a mechanism by which effects of insulin are mediated. Activity of liver and muscle soluble fractions declines on fasting and, for the latter tissue, possibly also on a low protein diet. Sap from fasting animals allows a much smaller response of isolated ribosomes to added amino acids. Availability of glutamate in amino acid mixtures may be of special importance. However, insulin can influence the activity of the sap fraction of diaphragm muscle during incubation without the presence of amino acids in the medium. Understanding of what mechanisms are involved will depend on resolution of the critical sap factors. Continue reading >>
How Insulin Works In The Body
Insulin is a hormone that has a hand in several processes in your body. Not only does it assist with metabolizing carbohydrates and storing glucose for energy in cells, it also helps utilize the fat, protein, and certain minerals you eat. Because this hormone is so important in helping your body use the foods you ingest, a problem with insulin can have widespread effects on all of your body's systems, tissues, and organs—either directly or indirectly. If you have type 2 diabetes, learning how insulin works can help you understand why so many other medical conditions are associated with diabetes, why certain lifestyle practices are beneficial, and how your body reacts to food. Where Insulin Is Produced Insulin is a hormone made up of a small polypeptide protein that is secreted by the pancreas, which acts as both an endocrine and exocrine gland. Endocrine glands are the system of glands that secrete hormones to regulate body functions, whereas exocrine glands aid in digestion. The pancreas sits behind the stomach, nestled in the curve of the duodenum (the first part of the small intestine), and contains clusters of cells called islets of Langerhans. Islets are made up of beta cells, which produce and release insulin into the bloodstream. How Insulin Works Insulin affects carbohydrate, protein, and fat metabolism. Your body breaks these nutrients down into sugar molecules, amino acid molecules, and lipid molecules. The body can also store and reassemble these molecules into more complex forms. Insulin causes the storage of these nutrients, while another pancreatic hormone called glucagon releases them from storage. Insulin is involved in your body's careful balancing act to keep your blood sugar levels within a normal range. In simple terms: If your blood sugar is high: Continue reading >>
Role Of Insulin And Other Related Hormones In Energy Metabolisma Review
Role of insulin and other related hormones in energy metabolismA review Accepted author version posted online: 05 Dec 2016 This review aims to review hormones mechanisms that affect fuel metabolism and are involved in regulation of blood glucose, dealing insulin and glucagon hormones, and includes other related hormones, which increase the blood glucose level: growth hormone, thyroxine, cortisol and adrenaline. However, this review focuses on insulin and glucagon hormones as widely, and on other related hormones as briefly. Insulin plays an important role in a decrease blood glucose concentration in hyperglycemic response to emergencies or stress by an increasing rate of glucose transport into the muscle cell of animals and facilitating glucose utilization and by maintaining normal blood glucose concentrations. Insulin is a hypoglycemic hormone, promoting the storage of metabolites in peripheral stores. While, glucagon is a hyperglycemic hormone, stimulates gluconeogenesisat the expense of peripheral stores by enhancing the hepatic removal of certain glucose precursors and stimulates lipolysis; however, it has not influence on peripheral protein stores directly. Insulin, glucagon and other related hormones regulate blood glucose concentrations and act on movement of glucose, amino acids and possibly volatile fatty acids between the liver and peripheral tissues directly. In another way, glucagon may be considered catabolic and insulin anabolic. In conclusion, insulin promotes body gain by stimulating protein and fat synthesis, growth hormone increases protein retention and decrease fat deposition. Growth hormone can alter the sensitivity of tissues to insulin. In contrast, catabolic hormones such as glucagon, epinephrine and glucocorticoids are provided for mobilization Continue reading >>
The Science Of Insulin
Insulin is perhaps the most well known of all hormones and in the halls of health, fitness, and fat loss. It is mostly maligned and drastically misunderstood. As with many things in health and fitness there is more to the simple story told about insulin. Insulin basics Insulin functions very much like your hands when you are eating. Just as it would be extremely difficult to eat without hands, insulin feeds the tissue of the body in the same way. Insulin is required to facilitate nutrient uptake in the cells. Without insulin, your cells would literally starve and die. Insulin is made in the beta cells of the pancreas and is released into the blood stream in response to food. It assures these nutrients get into the cell. Insulin’s primary job is to make sure the cells have enough glucose, and therefore it has a strong impact on blood sugar levels. In fact, glucose is the primary stimulator of insulin release. In response to food and/or stress, blood glucose levels will rise. Insulin is used to lower blood sugar and balance things back out. Insulin Resistance Insulin works by increasing the amount of glucose receptors on the membranes of cells. So, when insulin interacts with cellular physiology it results in an increased ability for the cell to take in glucose. When insulin is repeatedly secreted in large quantities, over time the cells become less sensitive to its message. This is analogous to walking into a room with a strong smell. When you first enter, you are acutely aware of the odor and may cover your nose in response. After several minutes however, the smell becomes diminished and you no longer smell it. This is what happens to the cells when they become insulin resistant. They no longer respond to insulin the same way. This has consequences for cellular energy Continue reading >>
Insulin
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.[5] 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.[6] 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.[6] Glucose production and secretion by the liver is strongly inhibited by high concentrations of insulin in the blood.[7] 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.[8] Their neighboring alpha cells, by taking their cues from the beta cells,[8] secrete glucagon into the blood in the opposite manner: increased secretion when blood glucose is low, and decreased secretion when glucose concentrations are high.[6][8] Glucagon, through stimulating the liver to release glucose by glycogenolysis and gluconeogenesis, has the opposite effect of insulin.[6][8] The secretion of insulin and glucagon into the Continue reading >>
Fatty Acids, Insulin Resistance, And Protein Metabolism
Fatty Acids, Insulin Resistance, and Protein Metabolism We are experimenting with display styles that make it easier to read articles in PMC. The ePub format uses eBook readers, which have several "ease of reading" features already built in. The ePub format is best viewed in the iBooks reader. You may notice problems with the display of certain parts of an article in other eReaders. Generating an ePub file may take a long time, please be patient. Fatty Acids, Insulin Resistance, and Protein Metabolism Accretion and maintenance of lean body mass, because of its fundamental role in health and disease, continues to be an area of intense investigation. By using sophisticated tracer isotopic methods, organ balance techniques, and molecular analysis of tissue samples in humans and animal models, a detailed analysis of the signaling pathway and metabolic fluxes has been possible. Despite these, understanding the regulatory mechanism of nitrogen/protein accretion and maintenance of lean body mass in vivo continues to be challenging. This is particularly difficult because of the adaptation of metabolism to various modifying influences, and because of the multiple levels of regulation in vivo. Yet, by careful studies, a number of investigators have systematically examined the influence of diverse modifiers on the physiology of protein synthesis and breakdown in humans in vivo. In this issue of JCEM, Katsanos et al. have examined, in healthy humans, the impact of elevated plasma fatty acids levels, induced by iv infusion of intralipid and heparin, on the responsiveness of the skeletal muscle protein synthesis and balance to an enterally administered essential amino acid mixture. By using isotopic tracers in combination with arteriovenous balance measurements across the leg and by 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 >>
