Definition of Islets of Langerhans Definition of Islets of Langerhans Causes of a Heart Attack Slideshow Islets of Langerhans: Known as the insulin -producing tissue, the islets of Langerhans do more than that. They are groups of specialized cells in the pancreas that make and secrete hormones. Named after the German pathologist Paul Langerhans (1847-1888), who discovered them in 1869, these cells sit in groups that Langerhans likened to little islands in the pancreas. There are five types of cells in an islet: alpha cells that make glucagon , which raises the level of glucose (sugar) in the blood; beta cells that make insulin; delta cells that make somatostatin which inhibits the release of numerous other hormones in the body; and PP cells and D1 cells, about which little is known. Degeneration of the insulin-producing beta cells is the main cause of type I (insulin-dependent) diabetes mellitus.

Last Editorial Review: 5/13/2016 islets of Langerhans | anatomy | Britannica.com Islets of Langerhans Alternative Titles: islands of Langerhans, pancreatic islets Related Topics endocrine system Islets of Langerhans, also called islands of Langerhans, irregularly shaped patches of endocrine tissue located within the pancreas of most vertebrates. They are named for the German physician Paul Langerhans, who first described them in 1869. The normal human pancreas contains about 1,000,000 islets. The islets consist of four distinct cell types, of which three (alpha, beta, and delta cells) produce important hormones ; the fourth component (C cells) has no known function. The islets of Langerhans are responsible for the endocrine function of the pancreas. Each islet … Encyclopædia Britannica, Inc. The most common islet cell, the beta cell, produces insulin , the major hormone in the regulation of carbohydrate, fat, and protein metabolism.

Insulin is crucial in several metabolic processes: it promotes the uptake and metabolism of glucose by the body’s cells; it prevents release of glucose by the liver; it causes muscle cells to take up amino acids, the basic components of protein; and it inhibits the breakdown and release of fats. The release of insulin from the beta cells can be triggered by growth hormone (somatotropin) or by glucagon, but the most important stimulator of insulin release is glucose; when the blood glucose level increases—as it does after a meal—insulin is released to counter it. The inability of the islet cells to make insulin or the failure to produce amounts sufficient to control blood glucose level are the causes of diabetes mellitus . The islets of Langerhans contain alpha, beta, and delta cells that produce glucagon, insulin, and … Encyclopædia Britannica, Inc. The alpha cells of the islets of Langerhans produce an opposing hormone, glucagon , which releases glucose from the liver and fatty acids from fat tissue. In turn, glucose and free fatty acids favour insulin release and inhibit glucagon release.

The delta cells produce somatostatin , a strong inhibitor of somatotropin, insulin, and glucagon; its role in metabolic regulation is not yet clear. Somatostatin is also produced by the hypothalamus and functions there to inhibit secretion of growth hormone by the pituitary gland . Learn More in these related articles: Islet Cells: Islets of Langerhans: Pancreatic Cell What are Islet Cells? The Islets of Langerhans The Islets of Langerhans are commonly referred to as "islets" (pronounced "EYE-lets"). Islets actually are clusters of cells, with each "islet" containing 3,000 to 4,000 cells. Scientists estimate there are 1 million islets in a healthy, adult pancreas. They make up only 1 to 2 percent of the entire organ. Within each islet are several types of cells, which work together to regulate blood sugar. One cell type is the beta cell. Beta cells sense sugar in the blood and release the necessary amount of insulin to maintain normal blood sugar levels.

The immune system mistakenly sees beta cells as "potential danger" and destroys them, causing type 1 diabetes . The loss of these cells means the body can no longer produce insulin, the hormone required to convert food into energy for the body’s cells. Although insulin-producing islet cells cease to function in persons with diabetes, the remaining 98 percent of the pancreas continues to function normally, producing digestive enzymes. Here at the DRI, we’re focused on restoring natural insulin production to normalize blood sugar control. One key strategy is islet transplantation -- taking healthy islets from a donor pancreas and transplanting them into patients with diabetes. We’ve already demonstrated that transplanted islets can function for more than 12 years. Much of our research is now aimed at increasing the supply of islet cells available for transplantation, to find the optimal site for transplantation, as well as eliminating the need for anti-rejection drugs . Islets are clusters of cells scattered throughout the pancreas, which include cells that sense sugar in the blood. Do you know how islet cells are isolated from the pancreas? View this video about the innovative method developed by DRI Director Dr. Camillo Ricordi that makes islet cell transplantation possible.

Islets of Langerhans are made of four different cell types. The majority are insulin-producing beta cells (shown in green) and glucagon-producing alpha cells (shown in red). The blue color is a marker used to locate the nucleus of the cells. Using Laser Scanning Cytometry (LSC), DRI scientists can study the physiology of the basic islet components to assess their viability before transplantation. Diabetes 16+ Diabetes 16+ Select from our full list of topics... A Islets of Langerhans Groups of pancreatic cells which make the hormones such as insulin which control the blood sugar levels. Specialised cells Cells which are adapted to carry out a specific function in the body Protein A polymer made up of amino acids joined by peptide bonds. The amino acids present and the order in which they occur vary from one protein to another. Pancreas An endocrine gland which produces insulin Insulin A hormone produced by the pancreas. It allows cells in the body to take in and store glucose. Hormone A chemical messenger produced by a particular gland or cells of the endocrine system.

Hormones are transported throughout the body in the blood stream but they produce a response only in specific target cells Glucose A type of sugar: a mono saccharide with 6 carbon atoms (a hexose sugar). Glucagon A hormone produced by the pancreas. It causes the liver to convert glycogen back to glucose and to release glucose into the bloodstream. Glossary A list of often difficult or specialised words with their definitions. Diabetes A disease resulting from a lack of insulin production by the pancreas or a loss of the cell response to insulin that causes a loss of control of the glucose balance of the body. What is diabetes? Diabetes is a condition where the amount of glucose in the blood is too high because the body cannot use it properly. The full name for this disorder is diabetes mellitus. The disorder is more commonly known as diabetes and this will be used throughout the resource. Contents The islets of Langerhans (Book, 2010) [WorldCat.org] Find more libraries Librarian? Claim your library to The islets of Langerhans Dordrecht ; New York : Springer, ©2010.

Series: WorldCat Summary: 'This book is a unique and thoughtful blend of critical background information and advances made in a multitude of areas of contemporary islet research. It is an essential reference book, the first of its kind in many years, for professionals as well as for the beginners interested in the study of islet physiology and diabetes. The book is unique in its breadth: it deals with anatomy, histology, ultra-structure, evolution and comparative anatomy, imaging, developmental biology, programming, apoptosis, mitochondrial function, metabolism, cellular signaling, electrophysiology, oscillation of hormone secretion, islets of model animals, immunology, proteomics, regenerative medicine, clinical advances, islet transplantation, and finally islet tumors. Individual chapters contributed by over a hundred experts and enthusiasts, not only provide a balanced view of the recent advances made in the respective fields, but also provide directions and thoughts for future research. Thanks to vivid and colorful illustrations, tables and sketches, the book as a whole, and the individual chapters make reading a pleasant experience. It is a valuable compilation that one would love to possess personally and buy as a present to a colleague.'--From books.google.com.hk. Read more...

Rating: You are connected to the University of Washington Libraries network Hide local services for this item Ebook Library Add library to Favorites Please choose whether or not you want other users to be able to see on your profile that this library is a favorite of yours. Allow this favorite library to be seen by others Keep this favorite library private Find a copy in the library Finding libraries that hold this item... Details xix, 798 pages : illustrations (some color) ; 25 cm. Contents: Microscopic anatomy of the human islet of Langerhans / P. In't Veld and M. Marichal -- The comparative anatomy of islets / R.S. Heller -- Approaches for imaging islets: recent advances and future prospects / U. Ahlgren and M. Gotthardt -- Islet cell development / A. Rojas [and others] -- High fat programming of beta-cell failure / M.E. Cerf -- Nutrient regulation of insulin secretion and beta-cell functional integrity / P. Newsholme, C. Gaudel and N.H. McClenaghan -- Electrophysiology of islet cells / G. Drews, P. Krippeit-Drews and M.

Dufer -- ATP-sensitive potassium channels in health and disease / R. Clark and P. Proks -- Role of mitochondria in beta-cell function and dysfunction / P. Maechler [and others] -- Basement membrane in pancreatic islet function / M. Kragl and E. Lammert -- Calcium signaling in the islets / M.S. Islam -- Electrical bursting, calcium oscillations, and synchronization of pancreatic islets / R. Bertram, A. Sherman and L.S. Satin -- Cyclic AMP signaling in pancreatic islets / B. Furman, W.K. Ong and N.J. Pyne -- Exocytosis in islet beta-cells / H. Kasai [and others] -- The novel roles of glucagon-like peptide-1, angiotensin II, and vitamin D in islet function / P.S. Leung and Q. Cheng -- Proteomics and islet research / M. Ahmed -- Wnt signaling in pancreatic islets / Z. Liu and J.F. Habener -- Molecular pathways underlying the pathogenesis of pancreatic alpha-cell dysfunction / D. Kawamori, H.J. Welters and R.N.

Kulkarni -- Mechanisms of pancreatic beta-cell apoptosis in diabetes and its therapies / J.D. Johnson and D.S. Luciani -- beta-cell function in obese-hyperglycemic mice [ob/ob Mice] / P. Lindstrom -- Islet structure and function in the GK rat / B. Portha [and others] -- The beta-cell in human type 2 diabetes / P. Marchetti [and others] -- Clinical approaches to preserve beta-cell function in diabetes / B.L. Wajchenberg -- Immunology of beta-cell destruction / D. La Torre and A. Lernmark -- Toll-like receptors and type 1 diabetes / D. Zipris -- Prevention of beta-cell destruction in autoimmune diabetes: current approaches and future prospects / S.K. Sedimbi and C.B. Sanjeevi -- In vivo regeneration of insulin-producing beta-cells / H.S. Jun -- Customized cell-based treatment options to combat autoimmunity and restore beta-cell function in type 1 diabetes mellitus: current protocols and future perspectives / F. Fandrich and H.

Ungefroren -- The programmable cell of monocytic origin (PCMO): a potential adult stem/progenitor cell source for the generation of islet cells / H. Ungefroren and F. Fandrich -- Islet isolation for clinical transplantation / T. Kin -- Human islet autotransplantation: the trail thus far and the highway ahead / M. Hermann, R. Margreiter and P. Hengster -- Modulation of early inflammatory reactions to promote engraftment and function of transplanted pancreatic islets in autoimmune diabetes / L. Piemonti, L.G. Guidotti and M. Battaglia -- Successes and disappointments with clinical islet transplantation / P. Cravedi [and others] -- Islet cell tumours / S. Ekeblad. Series Title: Md. Shahidul Islam, editor. Abstract: This book examines the molecular and cellular processes in islet development, gene expression, and physiology and reviews how a better understanding of the pancreatic islet will advance efforts to develop new therapeutic approaches for diabetes. Read more...

Reviews Editorial reviews Publisher Synopsis "It looks very comprehensive and covers all current areas of interest and includes chapters written by world renowned contributors - very nice!" Matthias von Herrath, MD Professor and Director, Center for Type 1 Diabetes Research La Jolla Institute for Allergy and Immunology, La Jolla CA, USA "This book will be welcomed by islet researchers and clinicians interested in the latest developments and theories from which new therapeutics for diabetes can emerge". Martha Pavlakis, MD Associate Professor of Medicine, Harvard Medical School Medical Director, Kidney and Pancreas Transplantation Beth Israel Deaconess Medical Center Boston, MA, USA "The field of islet biology is assuming increasing importance with the recognition that beta-cell dysfunction is a critical feature of type II diabetes. Improving b-cell function and/or b-cell mass may be the best approach to treating diabetes. Thus, the publication of a book covering so many aspects of this field is timely". Fred Levine, M.D., Ph.D.

Professor, Burnham Institute for Medical Research Director, Sanford Children's Health Research Center La Jolla, CA, USA "The growing prevalence of both type 1 and type 2 diabetes make islet cell biology a critical concern for a wide range of scientists and health professionals. From anatomy and developmental biology, through islet physiology and biochemistry, to issues of immunology and transplantation, this book is a terrific resource". Jonathan M.W.Slack, Ph.D., F.Med.Sci. Director, Stem Cell Institute, University of Minnesota, Medical School Minneapolis, MN, USA "This book allows you to enjoy an adventurous and instructive guided tour in the archipelago of the islets of Langerhans. A team of expert and enthusiastic explorers will not only conduct the voyager through almost all niches of this complex and fascinating environment, but also provide him with clues and keys for future exploration of still hidden sites". Prof. Pellegrino Masiello Dept. of Experimental Pathology, University of Pisa, Pisa, Italy "The pancreatic islet is a complex mini-organ whose dysfunction is critical in all forms of diabetes.

This book provides a comprehensive review of the molecular and cellular processes in islet development, gene expression, and physiology and reviews how a better understanding of the pancreatic islet will advance efforts to develop new therapeutic approaches for diabetes. This book should be quite useful for anyone interested in the pancreatic islet or diabetes". Alvin C. Powers, M.D. Joe C. Davis Chair in Biomedical Science Professor of Medicine, Molecular Physiology and Biophysics Director, Vanderbilt Diabetes Center Vanderbilt University Nashville, TN USA "A very timely book on the Islet of Langerhans that coincides with the realization that pancreatic ss-cell failure is key to all forms of diabetes mellitus and research in the field is exploding. It contains very thoughtful chapters, each by renown experts in their field, and tackles the complexity of this micro-organ in health and disease very comprehensively and thoughtfully. It will likely become a Reference for years to come for basic researchers, clinicians and students interested is diabetes research" Marc Prentki, PhD Professor of Nutrition and Biochemistry Canada Research Chair in Diabetes and Metabolism MDRC Director Montreal, QC Canada Read more... Add a review and share your thoughts with other readers. Be the first. Add a review and share your thoughts with other readers.

Be the first. Tags Add tags for "The islets of Langerhans". Be the first. Similar Items Science. Confirm this request You may have already requested this item. Please select Ok if you would like to proceed with this request anyway. Linked Data schema:datePublished "2010" ; schema:description "Microscopic anatomy of the human islet of Langerhans / P. In't Veld and M. Marichal -- The comparative anatomy of islets / R.S. Heller -- Approaches for imaging islets: recent advances and future prospects / U. Ahlgren and M. Gotthardt -- Islet cell development / A. Rojas [and others] -- High fat programming of beta-cell failure / M.E. Cerf -- Nutrient regulation of insulin secretion and beta-cell functional integrity / P. Newsholme, C. Gaudel and N.H. McClenaghan -- Electrophysiology of islet cells / G. Drews, P. Krippeit-Drews and M. Dufer -- ATP-sensitive potassium channels in health and disease / R. Clark and P. Proks -- Role of mitochondria in beta-cell function and dysfunction / P.

Maechler [and others] -- Basement membrane in pancreatic islet function / M. Kragl and E. Lammert -- Calcium signaling in the islets / M.S. Islam -- Electrical bursting, calcium oscillations, and synchronization of pancreatic islets / R. Bertram, A. Sherman and L.S. Satin -- Cyclic AMP signaling in pancreatic islets / B. Furman, W.K. Ong and N.J. Pyne -- Exocytosis in islet beta-cells / H. Kasai [and others] -- The novel roles of glucagon-like peptide-1, angiotensin II, and vitamin D in islet function / P.S. Leung and Q. Cheng -- Proteomics and islet research / M. Ahmed -- Wnt signaling in pancreatic islets / Z. Liu and J.F. Habener -- Molecular pathways underlying the pathogenesis of pancreatic alpha-cell dysfunction / D. Kawamori, H.J. Welters and R.N. Kulkarni -- Mechanisms of pancreatic beta-cell apoptosis in diabetes and its therapies / J.D. Johnson and D.S.

Luciani -- beta-cell function in obese-hyperglycemic mice [ob/ob Mice] / P. Lindstrom -- Islet structure and function in the GK rat / B. Portha [and others] -- The beta-cell in human type 2 diabetes / P. Marchetti [and others] -- Clinical approaches to preserve beta-cell function in diabetes / B.L. Wajchenberg -- Immunology of beta-cell destruction / D. La Torre and A. Lernmark -- Toll-like receptors and type 1 diabetes / D. Zipris -- Prevention of beta-cell destruction in autoimmune diabetes: current approaches and future prospects / S.K. Sedimbi and C.B. Sanjeevi -- In vivo regeneration of insulin-producing beta-cells / H.S. Jun -- Customized cell-based treatment options to combat autoimmunity and restore beta-cell function in type 1 diabetes mellitus: current protocols and future perspectives / F. Fandrich and H. Ungefroren -- The programmable cell of monocytic origin (PCMO): a potential adult stem/progenitor cell source for the generation of islet cells / H. Ungefroren and F.

Fandrich -- Islet isolation for clinical transplantation / T. Kin -- Human islet autotransplantation: the trail thus far and the highway ahead / M. Hermann, R. Margreiter and P. Hengster -- Modulation of early inflammatory reactions to promote engraftment and function of transplanted pancreatic islets in autoimmune diabetes / L. Piemonti, L.G. Guidotti and M. Battaglia -- Successes and disappointments with clinical islet transplantation / P. Cravedi [and others] -- Islet cell tumours / S. Ekeblad."@ en ; schema:description "'This book is a unique and thoughtful blend of critical background information and advances made in a multitude of areas of contemporary islet research. It is an essential reference book, the first of its kind in many years, for professionals as well as for the beginners interested in the study of islet physiology and diabetes.

The book is unique in its breadth: it deals with anatomy, histology, ultra-structure, evolution and comparative anatomy, imaging, developmental biology, programming, apoptosis, mitochondrial function, metabolism, cellular signaling, electrophysiology, oscillation of hormone secretion, islets of model animals, immunology, proteomics, regenerative medicine, clinical advances, islet transplantation, and finally islet tumors. Individual chapters contributed by over a hundred experts and enthusiasts, not only provide a balanced view of the recent advances made in the respective fields, but also provide directions and thoughts for future research. Thanks to vivid and colorful illustrations, tables and sketches, the book as a whole, and the individual chapters make reading a pleasant experience. It is a valuable compilation that one would love to possess personally and buy as a present to a colleague.'--From books.google.com.hk."@ en ; Islets of Langerhans | Colorado PROFILES Find journals in COLORADO Profiles by department and year. Contact Us If you have any questions or feedback please contact us . Islets of Langerhans "Islets of Langerhans" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) .

Descriptors are arranged in a hierarchical structure, which enables searching at various levels of specificity. MeSH information Definition | Details | More General Concepts | Related Concepts | More Specific Concepts Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types. The most abundant beta cells (50-80%) secrete INSULIN. Alpha cells (5-20%) secrete GLUCAGON. PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE. Delta cells (~5%) secrete SOMATOSTATIN. Descriptor ID Below are MeSH descriptors whose meaning is more general than "Islets of Langerhans". Anatomy [A] Below are MeSH descriptors whose meaning is more specific than "Islets of Langerhans". Islets of Langerhans This graph shows the total number of publications written about "Islets of Langerhans" by people in Profiles by year, and whether "Islets of Langerhans" was a major or minor topic of these publication.

Below are the most recent publications written about "Islets of Langerhans" by people in Profiles. Baker RL, Bradley B, Wiles TA, Lindsay RS, Barbour G, Delong T, Friedman RS, Haskins K. Cutting Edge: Nonobese Diabetic Mice Deficient in Chromogranin A Are Protected from Autoimmune Diabetes. J Immunol. 2016 Jan 01; 196(1):39-43. View in: PubMed El-Gohary Y, Wiersch J, Tulachan S, Xiao X, Guo P, Rymer C, Fischbach S, Prasadan K, Shiota C, Gaffar I, Song Z, Galambos C, Esni F, Gittes GK. Intraislet Pancreatic Ducts Can Give Rise to Insulin-Positive Cells. Endocrinology. 2016 Jan; 157(1):166-75. View in: PubMed Wenzlau JM, Frisch LM, Hutton JC, Fain PR, Davidson HW.

Changes in Zinc Transporter 8 Autoantibodies Following Type 1 Diabetes Onset: The Type 1 Diabetes Genetics Consortium Autoantibody Workshop. Diabetes Care. 2015 Oct; 38 Suppl 2:S14-20. View in: PubMed Wagner BD, Frank DN, Zipris D. Response to Comment on Alkanani et al. Alterations in Intestinal Microbiota Correlate With Susceptibility to Type 1 Diabetes. Diabetes 2015;64:3510-3520. Diabetes. 2015 Oct; 64(10):e41. View in: PubMed Bingley PJ, Rafkin LE, Matheson D, Steck AK, Yu L, Henderson C, Beam CA, Boulware DC. Use of Dried Capillary Blood Sampling for Islet Autoantibody Screening in Relatives: A Feasibility Study. Diabetes Technol Ther. 2015 Dec; 17(12):867-71.

View in: PubMed Sintov E, Nathan G, Knoller S, Pasmanik-Chor M, Russ HA, Efrat S. Inhibition of ZEB1 expression induces redifferentiation of adult human ß cells expanded in vitro. Sci Rep. 2015 Aug 12; 5:13024. View in: PubMed Michels A, Zhang L, Khadra A, Kushner JA, Redondo MJ, Pietropaolo M. Prediction and prevention of type 1 diabetes: update on success of prediction and struggles at prevention. Pediatr Diabetes. 2015 Nov; 16(7):465-84. View in: PubMed Beyerlein A, Liu X, Uusitalo UM, Harsunen M, Norris JM, Foterek K, Virtanen SM, Rewers MJ, She JX, Simell O, Lernmark Å, Hagopian W, Akolkar B, Ziegler AG, Krischer JP, Hummel S. Dietary intake of soluble fiber and risk of islet autoimmunity by 5 y of age: results from the TEDDY study. Am J Clin Nutr.

2015 Aug; 102(2):345-52. View in: PubMed Alkanani AK, Hara N, Gottlieb PA, Ir D, Robertson CE, Wagner BD, Frank DN, Zipris D. Alterations in Intestinal Microbiota Correlate With Susceptibility to Type 1 Diabetes. Diabetes. 2015 Oct; 64(10):3510-20. View in: PubMed Arnes L, Sussel L. Epigenetic modifications and long noncoding RNAs influence pancreas development and function. Trends Genet. 2015 Jun; 31(6):290-9. Transplant Surgery - Islet Transplant for Type 1 Diabetes Transplant Surgery » Conditions & Procedures » Islet Transplant for Type 1 Diabetes FOLLOW Sign up for delivery of news Islet Transplant for Type 1 Diabetes Islet cell transplantation places cells from an organ donor into the body of another person.

It is used experimentally to treat type 1 diabetes Image Courtesy of UCSF Diabetes Education Online Pancreatic Islets and Beta Cells The pancreas is an organ about the size of a hand located in the abdomen in the vicinity of the stomach, intestines, and other organs. It lies behind the stomach and in front of the spine. The pancreas produce juices that help digest food and hormones such as insulin and glucagon that maintain optimal blood sugar levels and help the body to use and store energy from food. Throughout the pancreas are clusters of cells called the islets of Langerhans. Islets are made up of several types of cells, including beta cells that make insulin. Insulin is a hormone that helps the body use glucose for energy. Insulin and Diabetes Diabetes develops when the body doesn't make enough insulin, cannot use insulin properly, or both, causing glucose to build up in the blood. Diabetes is a serious disease, which, if not controlled, can be life threatening. It is often associated with long-term complications that can affect every system and part of the body. Diabetes can contribute to eye disorders and blindness, heart disease, stroke, kidney failure, amputation, and nerve damage.

Type 1 Diabetes Type 1 diabetes results from the body's failure to produce insulin, the hormone that "unlocks" the cells of the body, allowing glucose to enter and fuel them. It is an autoimmune disease in which the body views the beta cells (insulin producing cells found in the islets of the pancreas) as a foreign substance, so the patient's immune system attacks the islets and kills them. It is estimated that 5-10% of Americans who are diagnosed with diabetes have type 1 diabetes. Most people with type 1 diabetes do not have a family history of the disease and there is no way currently to prevent the onset of type1 diabetes. Image courtesy of Clinical Islet Transplantation (CIT) Consortium, sponsored by National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) Insulin therapy, given by injection or insulin pump, is life-saving. However, it's not perfect. Most people with type 1 diabetes still have blood glucose levels that are above normal. This puts them at risk for the long-term complications of diabetes. Some people have what doctors call labile, or brittle, diabetes.

Blood glucose levels swing from high to low despite the best insulin plans. Because of this, long-term type 1 diabetic survivors often develop vascular complications, such as diabetic retinopathy, an eye disease that can cause poor vision and blindness, and diabetic nephropathy, a kidney disease that can lead to kidney failure. Hypoglycemia Unawareness Those who are able to keep their blood glucose levels near normal often have trouble with low blood glucose (hypoglycemia). And after many years, some people lose the early symptoms that warn them that their blood glucose level is dropping. This is called hypoglycemia unawareness and raises the risk of severe hypoglycemia. Hypoglycemia unawareness is a life-threatening condition that is not easily treatable with medication and is characterized by reduced or absent warning signals for hypoglycemia. Some Type 1 diabetic patients have been known to set their alarms to wake them several times a night out of fear they may have a catastrophic hypoglycemic episode while asleep. For such individuals, transplantation of pancreatic islets is a viable treatment option to consider.

Islet Cell Transplantation Procedure In islet transplantation, islets are taken from the pancreas of a deceased organ donor. The islets are purified, processed, and transferred into another person. Once implanted, the beta cells in these islets begin to make and release insulin. Researchers hope that islet transplantation will help people with type 1 diabetes live without daily injections of insulin. Researchers use specialized enzymes to remove islets from the pancreas of a deceased donor. Because the islets are fragile, transplantation occurs soon after they are removed. Typically a patient receives at least 10,000 islet "equivalents" per kilogram of body weight, extracted from two donor pancreases. Patients often require two transplants to achieve insulin independence. Some transplants have used fewer islet equivalents taken from a single donated pancreas. Transplants are often performed by a radiologist, who uses x rays and ultrasound to guide placement of a catheter-a small plastic tube-through the upper abdomen and into the portal vein of the liver. The islets are then infused slowly through the catheter into the liver. The patient receives a local anesthetic and a sedative.

In some cases, a surgeon may perform the transplant through a small incision, using general anesthesia. Islets extracted from a donor pancreas are infused into the liver. Once implanted, the beta cells in the islets begin to make and release insulin. Image courtesy of University of Alberta and the Clinical Islet Transplantation (CIT) Consortium, sponsored by National Institute of Diabetes & Digestive & Kidney Diseases (NIDDK) and National Institute of Allergy and Infectious Diseases (NIAID) Islets begin to release insulin soon after transplantation. However, full islet function and new blood vessel growth associated with the islets take time. The doctor will order many tests to check blood glucose levels after the transplant, and insulin is usually given until the islets are fully functional. Benefits and Risks Islet Transplantation Benefits The goal of islet transplantation is to infuse enough islets to control the blood glucose level without insulin injections. Other benefits may include improved glucose control and prevention of potentially dangerous episodes of hypoglycemia.

Because good control of blood glucose can slow or prevent the progression of complications associated with diabetes, such as heart disease, kidney disease, and nerve or eye damage, a successful transplant may reduce the risk of these complications. Risks Risks of islet transplantation include the risks associated with the transplant procedure-particularly bleeding and blood clots-and side effects from the immunosuppressive drugs that transplant recipients must take to stop the immune system from rejecting the transplanted islets. Most people need two infusions at different times to get enough islets that are working, and some need three. So, even if islet transplantation is found to be effective, currently, there are not enough donor pancreases available to treat everyone with type 1 diabetes. Immunosuppression and Rejection As with any organ transplant, the recipient of an islet transplant must take drugs every day to keep the body from rejecting the islets. The immune system is programmed to destroy bacteria, viruses, and tissue it recognizes as "foreign," including transplanted islets. In addition, the autoimmune response that destroyed transplant recipients' own islets in the first place can recur and attack the transplanted islets. These drugs put the person at risk for infections and certain cancers.

They can also cause side effects that range from mild to severe. Some people who received an islet transplant have had to stop taking these medications, because of side effects and then their new islets stopped working. New Immunosuppression Protocols The Edmonton protocol introduced the use of a new combination of immunosuppressive drugs, also called anti-rejection drugs, including daclizumab (Zenapax), sirolimus (Rapamune), and tacrolimus (Prograf). Daclizumab is given intravenously right after the transplant and then discontinued. Sirolimus and tacrolimus, the two main drugs that keep the immune system from destroying the transplanted islets, must be taken for life or for as long as the islets continue to function. These drugs have significant side effects and their long-term effects are still not fully known. Immediate side effects of immunosuppressive drugs may include mouth sores and gastrointestinal problems, such as stomach upset and diarrhea. Patients may also have increased blood cholesterol levels, hypertension, anemia, fatigue, decreased white blood cell counts, decreased kidney function, and increased susceptibility to bacterial and viral infections. Taking immunosuppressive drugs also increases the risk of tumors and cancer.

Researchers continue to develop and study modifications to the Edmonton protocol drug regimen, including the use of new drugs and new combinations of drugs designed to help reduce destruction of transplanted islets and promote their successful implantation. These therapies may help transplant recipients achieve better function and durability of transplanted islets with fewer side effects. The ultimate goal is to achieve immune tolerance of the transplanted islets, where the patient's immune system no longer recognizes the islets as foreign. If achieved, immune tolerance would allow patients to maintain transplanted islets without long-term immunosuppression. Researchers are also trying to find new approaches that will allow successful transplantation without the use of immunosuppressive drugs. For example, one study is testing the transplantation of islets that are encapsulated with a special coating designed to prevent rejection. Shortage of Islets A major obstacle to widespread use of islet transplantation is the shortage of islets. Although organs from about 7,000 deceased donors become available each year in the United States, fewer than half of the donated pancreases are suitable for whole organ pancreas transplantation or for harvesting of islets-enough for only a small percentage of those with type 1 diabetes.

However, researchers are pursuing various approaches to solve this problem, such as transplanting islets from a single donated pancreas, from a portion of the pancreas of a living donor, or from pigs. Researchers have transplanted pig islets into other animals, including monkeys, by encapsulating the islets or by using drugs to prevent rejection. Another approach is creating islets from other types of cells, such as stem cells. New technologies could then be employed to grow islets in the laboratory. Note: The information above was reproduced or derived from the following public domain sources: The National Digestive Diseases Information Clearinghouse (NDDIC) , the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Reference Collection, and MedlinePlus, a service of the National Library of Medicine and National Institutes of Health (NIH), The Clinical Islet Transplantation (CIT) Consortium is a network of clinical centers and a data coordinating center established in 2004 to conduct studies of islet transplantation in patients with type 1 diabetes, also funded by the NIH and NIDDK, and Diabetes Education Online, UCSF Diabetes Teaching Center's Diabetes Education Online.

FOLLOW Islets of Langerhans (Pancreas) - YouTube Islets of Langerhans (Pancreas) Want to watch this again later? Sign in to add this video to a playlist. Need to report the video? Sign in to report inappropriate content. The interactive transcript could not be loaded. Loading... Rating is available when the video has been rented. This feature is not available right now. Please try again later. Published on Oct 7, 2014 Islets of Langerhans - RightDiagnosis.com Islets of Langerhans Introduction: Islets of Langerhans Description of Islets of Langerhans Islets of Langerhans: cell clusters in the pancreas that form the endocrine part of that organ; secrete insulin and other hormones. Source: WordNet 2.1 Islets of Langerhans: Irregular microscopic structures consisting of cords of endocrine cells that are scattered throughout the PANCREAS among the exocrine acini. Each islet is surrounded by connective tissue fibers and penetrated by a network of capillaries. There are four major cell types.

The most abundant beta cells (50-80%) secrete INSULIN . Alpha cells (5-20%) secrete GLUCAGON . PP cells (10-35%) secrete PANCREATIC POLYPEPTIDE . Delta cells (~5%) secrete SOMATOSTATIN . Source: MeSH 2007 Islets of Langerhans: Related Topics These medical condition or symptom topics may be relevant to medical information for Islets of Langerhans:

Question: Where would you find the islets of Langerhans?
Answer: Pancreas