What Limits Does The Body Maintain Blood Glucose Within

Kidneys And Diabetes

Tweet The kidneys are remarkable organs of the human body that are responsible for many essential regulatory roles, including filtering the blood to keep it clean and chemically balanced. Diabetes, however, can cause this vital filtering system to break down. High levels of blood sugar can damage the kidneys and cause them to fail, thus eliminating their ability to filter out waste, which over time can lead to kidney disease (nephropathy). What are the Kidneys? The kidneys are bean-shaped organs that are located near the middle of the back, just below the rib cage with one on each side of the spine. Of the many roles they perform, one of the most important is the removal of waste products from the blood, which come from food and the normal breakdown of active tissues, such as muscles. Other key functions of the kidneys include the secretion of three important hormones: Erythropoietin - which is released in response to hypoxia (low levels of oxygen at tissue level) to stimulate the production of red blood cells in the bone marrow. Calcitriol - the active form of vitamin D, which helps maintain calcium for bones and for normal chemical balance in the body Renin - an enzyme involved in the regulation of blood pressure The Kidneys and Blood Sugar Levels Each kidney is made up of millions of tiny blood vessels called nephrons, which act as filters to help keep the blood clean. Each nephron interlinks with a small tube to keep useful substances, such as proteins and red blood cells, in the bloodstream and allow extra fluid and waste products to pass through, where they become part of the urine. This filtration system can, however, be damaged by high levels of blood sugar. Excess glucose in the bloodstream can cause the kidneys to filter too much blood. Over time, this extra w Continue reading >>

Pancreatic Regulation Of Glucose Homeostasis

Go to: The pancreas is an exocrine and endocrine organ The pancreas has key roles in the regulation of macronutrient digestion and hence metabolism/energy homeostasis by releasing various digestive enzymes and pancreatic hormones. It is located behind the stomach within the left upper abdominal cavity and is partitioned into head, body and tail. The majority of this secretory organ consists of acinar—or exocrine—cells that secrete the pancreatic juice containing digestive enzymes, such as amylase, pancreatic lipase and trypsinogen, into the ducts, that is, the main pancreatic and the accessory pancreatic duct. In contrast, pancreatic hormones are released in an endocrine manner, that is, direct secretion into the blood stream. The endocrine cells are clustered together, thereby forming the so-called islets of Langerhans, which are small, island-like structures within the exocrine pancreatic tissue that account for only 1–2% of the entire organ (Figure 1).1 There are five different cell types releasing various hormones from the endocrine system: glucagon-producing α-cells,2 which represent 15–20% of the total islet cells; amylin-, C-peptide- and insulin-producing β-cells,2 which account for 65–80% of the total cells; pancreatic polypeptide (PP)-producing γ-cells,3 which comprise 3–5% of the total islet cells; somatostatin-producing δ-cells,2 which constitute 3–10% of the total cells; and ghrelin-producing ɛ-cells,4 which comprise <1% of the total islet cells. Each of the hormones has distinct functions. Glucagon increases blood glucose levels, whereas insulin decreases them.5 Somatostatin inhibits both, glucagon and insulin release,6 whereas PP regulates the exocrine and endocrine secretion activity of the pancreas.3, 7 Altogether, these hormones regul Continue reading >>

Homeostasis Of Glucose Levels: Hormonal Control And Diabetes

Homeostasis According to the Centers for Disease Control and Prevention, there are almost 26 million people in the United States alone that have diabetes, which is 8.3% of the total U.S. population. With so many Americans suffering from diabetes, how do we treat all of them? Do all of these people now need insulin shots, or are there other ways to treat, or prevent, diabetes? In order to answer these questions, we must first understand the fundamentals of blood glucose regulation. As you may remember, homeostasis is the maintenance of a stable internal environment within an organism, and maintaining a stable internal environment in a human means having to carefully regulate many parameters, including glucose levels in the blood. There are two major ways that signals are sent throughout the body. The first is through nerves of the nervous system. Signals are sent as nerve impulses that travel through nerve cells, called neurons. These impulses are sent to other neurons, or specific target cells at a specific location of the body that the neuron extends to. Most of the signals that the human body uses to regulate body temperature are sent through the nervous system. The second way that signals can be sent throughout the body is through the circulatory system. These signals are transmitted by specific molecules called hormones, which are signaling molecules that travel through the circulatory system. In this lesson, we'll take a look at how the human body maintains blood glucose levels through the use of hormone signaling. Homeostasis of Blood Glucose Levels Glucose is the main source of fuel for the cells in our bodies, but it's too big to simply diffuse into the cells by itself. Instead, it needs to be transported into the cells. Insulin is a hormone produced by the panc Continue reading >>

Blood Glucose Regulation

Glucose is needed by cells for respiration. It is important that the concentration of glucose in the blood is maintained at a constant level. Insulin is a hormone produced by the pancreas that regulates glucose levels in the blood. How glucose is regulated Glucose level Effect on pancreas Effect on liver Effect on glucose level too high insulin secreted into the blood liver converts glucose into glycogen goes down too low insulin not secreted into the blood liver does not convert glucose into glycogen goes up Use the animation to make sure you understand how this works. You have an old or no version of flash - you need to upgrade to view this funky content! Go to the WebWise Flash install guide Glucagon – Higher tier The pancreas releases another hormone, glucagon, when the blood sugar levels fall. This causes the cells in the liver to turn glycogen back into glucose which can then be released into the blood. The blood sugar levels will then rise. Now try a Test Bite- Higher tier. Diabetes is a disorder in which the blood glucose levels remain too high. It can be treated by injecting insulin. The extra insulin allows the glucose to be taken up by the liver and other tissues, so cells get the glucose they need and blood-sugar levels stay normal. There are two types of diabetes. Type 1 diabetes Type 1 diabetes is caused by a lack of insulin. It can be controlled by: monitoring the diet injecting insulin People with type 1 diabetes have to monitor their blood sugar levels throughout the day as the level of physical activity and diet affect the amount of insulin required. Type 2 diabetes Type 2 diabetes is caused by a person becoming resistant to insulin. It can be controlled by diet and exercise. There is a link between rising levels of obesity (chronic overweight) and i Continue reading >>

How Is Blood Glucose Maintained In The Body?

The control of blood glucose levels is an example of homeostasis. The human body requires glucose for normal respiration of cells, but the blood levels is in a narrow range. Insulin and glucagon are hormones released from the pancreas into the blood stream. They are called endocrine hormones, because they are in the blood stream (endocrine). How Insulin Controls Blood Glucose Insulin is secreted from the islet cells in the pancreas - in beta cells. HIGH blood glucose stimulates the release of insulin. There is a low level of insulin secreted by the pancreas, but in high glucose levels, more insulin is released into the blood stream. LOW blood glucose results in less secretion of insulin. In HIGH blood glucose, insulin in the blood stream causes glucose to enter cells resulting in a net reduction in blood glucose - into the normal range. In LOW blood glucose, more glucagon is released. The Effect of Glucagon On Blood Glucose Glucagon is also released by the pancreas, but it acts on liver cells to release glucose contained in glycogen molecules - this is called glycogenolysis (the breakdown of glycogen into glucose). Glucagon can also stimualte the liver to produce glucose out of other nutrients in the body, like proteins. If glucose levels are too low then glucagon is released, which results in an increase in blood glucose back to the normal range. 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 >>

What Is Normal Blood Sugar?

Blood sugar, or glucose, is an important source of energy and provides nutrients to your body's organs, muscles and nervous system. The body gets glucose from the food you eat, and the absorption, storage and production of glucose is regulated constantly by complex processes involving the small intestine, liver and pancreas. Normal blood sugar varies from person to person, but a normal range for fasting blood sugar (the amount of glucose in your blood six to eight hours after a meal) is between 70 and 100 milligrams per deciliter. For most individuals, the level of glucose in the blood rises after meals. A normal blood-sugar range after eating is between 135 and 140 milligrams per deciliter. These variations in blood-sugar levels, both before and after meals, are normal and reflect the way that glucose is absorbed and stored in the body. After you eat, your body breaks down the carbohydrates in food into smaller parts, including glucose, which can be absorbed by the small intestine. As the small intestine absorbs glucose, the pancreas releases insulin, which stimulates body tissues and causes them to absorb this glucose and metabolize it (a process known as glycogenesis). This stored glucose (glycogen) is used to maintain healthy blood-sugar levels between meals. When glucose levels drop between meals, the body takes some much-needed sugar out of storage. The process is kicked off by the pancreas, which releases a hormone known as glucagon, which promotes the conversion of stored sugar (glycogen) in the liver back to glucose. The glucose is then released into the bloodstream. When there isn't enough glucose stored up to maintain normal blood-sugar levels, the body will even produce its own glucose from noncarbohydrate sources (such as amino acids and glycerol). This pro Continue reading >>

How To Stabilize Your Blood Sugar

Life with type 2 diabetes can sometimes seem like an hourly or even minute-by-minute effort to stabilize your blood sugar. All of the recommendations and drugs you’ve been given as part of your type 2 diabetes treatment plan are intended to help you reach — and keep — healthy blood sugar levels most of the time. But doctors are learning that to control type 2 diabetes well, better information about why blood sugar matters and how to manage it is essential. The Facts About Diabetes and Blood Sugar As the American Diabetes Association (ADA) explains, your body needs sugar (glucose) for fuel, and there’s a fairly complicated process that makes it possible for your body to use that sugar. Insulin, which is made by the pancreas, is the hormone that enables the cells in your body to take advantage of sugar. Type 2 diabetes occurs when your body isn’t able to remove sugar from your blood. This can happen if your body stops being sensitive to insulin or if it starts to respond in a delayed or exaggerated way to changes in your blood sugar. Diabetes is signaled by an elevated blood sugar level of more than 126 milligrams per deciliter (mg/dL) for a fasting blood test, or more than 200 mg/dL at any time during the day. It can also be indicated by a hemoglobin A1C level of 6.5 percent or higher, a measure of the percentage of blood sugar attached to hemoglobin in the blood during the past two to three months. (Hemoglobin is a protein in red blood cells that transports oxygen throughout the body. So an A1C of 6.5 means that 6.5 percent of your red blood cells have sugar attached to them.) Unchecked high blood sugar gradually damages the blood vessels in your body. Over the long term, this slow, progressive harm can lead to a dangerous loss of sensation in your legs and fe Continue reading >>

How Insulin And Glucagon Work To Regulate Blood Sugar Levels

The pancreas secretes insulin and glucagon, both of which play a vital role in regulating blood sugar levels. The two hormones work in balance. If the level of one hormone is outside the ideal range, blood sugar levels may spike or drop. Together, insulin and glucagon help keep conditions inside the body steady. When blood sugar is too high, the pancreas secretes more insulin. When blood sugar levels drop, the pancreas releases glucagon to bring them back up. Blood sugar and health The body converts carbohydrates from food into sugar (glucose), which serves as a vital source of energy. Blood sugar levels vary throughout the day but, in most instances, insulin and glucagon keep these levels normal. Health factors including insulin resistance, diabetes, and problems with diet can cause a person's blood sugar levels to soar or plummet. Blood sugar levels are measured in milligrams per decilitre (mg/dl). Ideal blood sugar ranges are as follows: Before breakfast - levels should be less than 100 mg/dl for a person without diabetes and 70-130 mg/dl for a person with diabetes. Two hours after meals - levels should be less than 140 mg/dl for a person without diabetes and less than 180 mg/dl for a person with diabetes. Blood sugar regulation Blood sugar levels are a measure of how effectively an individual's body uses glucose. When the body does not convert enough glucose for use, blood sugar levels remain high. Insulin helps the body's cells absorb glucose, lowering blood sugar and providing the cells with the glucose they need for energy. When blood sugar levels are too low, the pancreas releases glucagon. Glucagon forces the liver to release stored glucose, which causes the blood sugar to rise. Insulin and glucagon are both released by islet cells in the pancreas. These cells Continue reading >>

Insulin Lowers Blood Glucose By Increasing Glucose Uptake In Muscle And Adipose Tissue And By Promoting Glycolysis And Glycogenesis In Liver And Muscle.

Glucose Homeostasis and Starvation Glucose Homeostasis: the balance of insulin and glucagon to maintain blood glucose. Insulin: secreted by the pancreas in response to elevated blood glucose following a meal. Insulin:Glucagon Ratio: everything that happens to glucose, amino acids and fat in the well fed state depends upon a high insulin to glucagon ratio. Glucagon: a fall in blood glucose increases the release of glucagon from the pancreas to promote glucose production. Glucose Tolerance Test: evaluates how quickly an individual can restore their blood glucose to normal following ingestion of a large amount of glucose, i.e. measures an individuals ability to maintain glucose homeostasis Diabetic: can not produce or respond to insulin so thus has a very low glucose tolerance Glucose, Protein and Fat Pathways: Obese Individuals: even with prolonged medically supervised fasting have plasma glucose levels that remain relatively constant even after three months. Glucose / Fatty Acid / Ketone Body Cycle: "explains the reciprocal relationship between the oxidation of glucose versus fatty acids or ketone bodies" Principal Hormone Effects on the Glucose-Fatty Acid Cycle: Under conditions of CHO stress (lack of CHO's): There is depletion of liver glycogen stores Fatty acids are mobilized from adipose and their rate of oxidation by muscle is increased, which in turn decreases glucose utilization. Glucagon signals fat mobilization. Under conditions of plentiful CHO's: Fatty acid release by adipose is reduced by insulin, thus decreasing fatty acid oxidation. Glucose use by the muscles increases. These responses stabilize blood glucose. The regulatory effect of fatty acid oxidation on glucose utilization is logical: 1) the small reserves of CHO in the body 2) the obligatory requireme 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 >>

Carbohydrates And Blood Sugar

When people eat a food containing carbohydrates, the digestive system breaks down the digestible ones into sugar, which enters the blood. As blood sugar levels rise, the pancreas produces insulin, a hormone that prompts cells to absorb blood sugar for energy or storage. As cells absorb blood sugar, levels in the bloodstream begin to fall. When this happens, the pancreas start making glucagon, a hormone that signals the liver to start releasing stored sugar. This interplay of insulin and glucagon ensure that cells throughout the body, and especially in the brain, have a steady supply of blood sugar. Carbohydrate metabolism is important in the development of type 2 diabetes, which occurs when the body can’t make enough insulin or can’t properly use the insulin it makes. Type 2 diabetes usually develops gradually over a number of years, beginning when muscle and other cells stop responding to insulin. This condition, known as insulin resistance, causes blood sugar and insulin levels to stay high long after eating. Over time, the heavy demands made on the insulin-making cells wears them out, and insulin production eventually stops. Glycemic index In the past, carbohydrates were commonly classified as being either “simple” or “complex,” and described as follows: Simple carbohydrates: These carbohydrates are composed of sugars (such as fructose and glucose) which have simple chemical structures composed of only one sugar (monosaccharides) or two sugars (disaccharides). Simple carbohydrates are easily and quickly utilized for energy by the body because of their simple chemical structure, often leading to a faster rise in blood sugar and insulin secretion from the pancreas – which can have negative health effects. Complex carbohydrates: These carbohydrates have mo Continue reading >>

Understanding Diabetes -- Diagnosis And Treatment

Your doctor may suspect you have diabetes if you have some risk factors for diabetes, or if you have high levels of blood sugar in your urine. Your blood sugar (also called blood glucose) levels may be high if your pancreas is producing little or no insulin (type 1 diabetes), or if the body is not responding normally to insulin (type 2 diabetes). Getting diagnosed begins with one of three tests. in most cases, your doctor will want to repeat a test that is high in order to confirm the diagnosis: A fasting glucose test is a test of your blood sugar levels taken in the morning before you have eaten. A level of 126 mg/dL or higher may mean that you have diabetes. An oral glucose tolerance test (OGTT) entails drinking a beverage containing glucose and then having your blood glucose levels checked every 30 to 60 minutes for up to 3 hours. If the glucose level is 200 mg/dL or higher at 2 hours, then you might have diabetes. The A1c test is a simple blood test that shows your average blood sugar levels for the past 2-3 months. An A1c level of 6.5% or higher may mean you have diabetes. Your doctor may also suggest a zinc transporter 8 autoantibody (ZnT8Ab) test. This blood test -- along with other information and test results -- can help determine if a person has type 1 diabetes instead of another type. The goal of having the ZnT8Ab test is a prompt and accurate diagnosis and that can lead to timely treatment. Diabetes is a serious disease that you cannot treat on your own. Your doctor will help you make a diabetes treatment plan that is right for you -- and that you can understand. You may also need other health care professionals on your diabetes treatment team, including a foot doctor, nutritionist, eye doctor, and a diabetes specialist (called an endocrinologist). Treatment Continue reading >>

How To Lower Blood Glucose Levels

Blood sugar (glucose) is at the heart of diabetes management. Diabetes develops when your pancreas can no longer produce insulin in sufficient quantity, or your body becomes less sensitive to the insulin you produce. Without enough effective insulin, your blood sugar levels can get out of control. High blood glucose (hyperglycemia) is most common in type 2 diabetes. But any person with diabetes can have bouts of high blood sugar. Lowering your blood sugar is crucial to both short-term and long-term diabetes management. When left untreated, hyperglycemia can cause: eye damage cardiovascular disease kidney failure nerve damage (neuropathy) skin and gum infections joint problems diabetic coma Many people with diabetes can detect hyperglycemia. According to the Mayo Clinic, signs of high blood sugar start to develop when levels reach more than 200 mg/dL. Some common symptoms include: sudden, excessive fatigue severe headaches blurry vision increased urination abdominal pain nausea dry mouth confusion The goal is to prevent hyperglycemia before it starts. It can develop suddenly, but in many cases high blood sugar develops over the course of several days. Symptoms worsen the longer you experience elevated blood sugar. The key is knowing where your blood sugar levels stand. Regular blood glucose monitoring is essential, especially in type 2 diabetes. The American Heart Association (AHA) recommends a range of 70 to 130 mg/dL before meals, and blood glucose less than 180 mg/dL after eating. Dietary changes are among the first actions taken by diabetics. Not only does a healthy diet make you feel good, but you can also lower your blood sugar during the process. Carbohydrates are often a source of criticism because they affect glucose more than any other food group. But it’s im Continue reading >>

How Blood Sugar Affects Your Body

When you have diabetes, your blood sugar (glucose) levels may be consistently high. Over time, this can damage your body and lead to many other problems. How much sugar in the blood is too much? And why is high glucose so bad for you? Here’s a look at how your levels affect your health. They're less than 100 mg/dL after not eating (fasting) for at least 8 hours. And they're less than 140 mg/dL 2 hours after eating. During the day, levels tend to be at their lowest just before meals. For most people without diabetes, blood sugar levels before meals hover around 70 to 80 mg/dL. For some people, 60 is normal; for others, 90. What's a low sugar level? It varies widely, too. Many people's glucose won't ever fall below 60, even with prolonged fasting. When you diet or fast, the liver keeps your levels normal by turning fat and muscle into sugar. A few people's levels may fall somewhat lower. Doctors use these tests to find out if you have diabetes: Fasting plasma glucose test. The doctor tests your blood sugar levels after fasting for 8 hours and it’s higher than 126 mg/dL. Oral glucose tolerance test. After fasting for 8 hours, you get a special sugary drink. Two hours later your sugar level is higher than 200. Random check. The doctor tests your blood sugar and it’s higher than 200, plus you’re peeing more, always thirsty, and you’ve gained or lost a significant amount of weight. He’ll then do a fasting sugar level test or an oral glucose tolerance test to confirm the diagnosis. Any sugar levels higher than normal are unhealthy. Levels that are higher than normal, but not reaching the point of full-blown diabetes, are called prediabetes. According to the American Diabetes Association, 86 million people in the U.S. have this condition, which can lead to diabetes Continue reading >>