Adipose tissue is an anatomical term for loose connective tissue composed of adipocytes. Its main role is to store energy in the form of fat, although it also cushions and insulates the body. It has an important endocrine function in producing recently-discovered hormones such as leptin, resistin and TNFα. Anatomical drawing of the human muscles from the Encyclopédie. ... Connective tissue is any type of biological tissue with an extensive extracellular matrix and often serves to support, bind together, and protect organs. ... Adipocytes are cells present in adipose tissue, specialized in storing energy as fat. ... Fat is one of the three main classes of food and, at approximately 38 kJ (9 kilocalories) per gram, as compared to sugar with 17 kJ (4 kcal) per gram or ethanol with 29 kJ (7 kcal) per gram, the most concentrated form of metabolic energy available to humans. ... This page refers to thermal insulation. ... The endocrine system is a control system of ductless endocrine glands that secrete chemical messengers called hormones that circulate within the body via the bloodstream to affect distant organs. ... A hormone (from Greek horman - to set in motion) is a chemical messenger from one cell (or group of cells) to another. ... Leptin is a protein hormone produced by adipose tissue. ... Resistin is a hormone secreted by adipose tissue. ... In medicine, tumor necrosis factor alpha (TNFα, cachexin or cachectin) is an important cytokine involved in systemic inflammation and the acute phase response. ...

Anatomical features

Adipose tissue is primarily located beneath the skin, but is also found around internal organs. In the skin, it accumulates in the deepest level, the subcutaneous layer, providing insulation from heat and cold. Around organs, it provides protective padding. It also functions as a reserve of nutrients. Model of the layers of human skin In zootomy and dermatology, skin is an organ of the integumentary system; which is composed of a layer of tissues that protect underlying muscles and organs. ... In biology, an organ (Latin organum: instrument, tool) is a group of tissues, which perform a specific function or group of functions. ... The subcutis is the layer of tissue directly underlying the cutis. ...

In a severely obese person, excess adipose tissue hanging downward from the abdomen is referred to as a panniculus (or pannus). A panniculus complicates surgery of the morbidly obese, and may remain as a literal "apron of skin" if a severely obese person loses most of the excess weight (as after a bypass). Obesity is an excess storage of fat and can affect any mammal, such as the mouse on the left. ... Pannus is a medical term for a hanging flap of skin. ...

Adipose tissue has an "intracellular matrix," rather than an extracellular one. Adipose tissue is divided into lobes by small blood vessels. The cells of this layer are adipocytes. The arterial system The blood vessels are part of the circulatory system and function to transport blood throughout the body. ... Cells in culture, stained for keratin (red) and DNA (green) The cell is the structural and functional unit of all living organisms, sometimes called the building blocks of life. ... Adipocytes are cells present in adipose tissue, specialized in storing energy as fat. ...

Physiology

Free fatty acid is "liberated" from lipoproteins by lipoprotein lipase (LPL) and enters the adipocyte, where it is reassembled into triglycerides by esterising it onto glycerol. In chemistry, especially biochemistry, a fatty acid is a carboxylic acid (or organic acid), often with a long aliphatic tail (long chains), either saturated or unsaturated. ... A lipoprotein is a biochemical assembly that contains both proteins and lipids and may be structural or catalytic in function. ... Lipoprotein lipase (EC 3. ... Triglycerides (also known as triacylglycerols or triacylglycerides) are glycerides in which the glycerol is esterified with three fatty acids. ... In organic chemistry and biochemistry esters are substances where an organic group replaces a hydrogen atom (or more than one) in an oxygen acid. ... ...

Fat cells have an important physiological role in maintaining triglyceride and free fatty acid levels, as well as determining insulin resistance. Abdominal fat has a different metabolic profile—being more prone to induce insulin resistance. This explains to a large degree why central obesity is a marker of impaired glucose tolerance and is an independent risk factor for cardiovascular disease (even in the absence of diabetes mellitus and hypertension). Physiology (in Greek physis = nature and logos = word) is the study of the mechanical, physical, and biochemical functions of living organisms. ... Triglycerides (also known as triacylglycerols or triacylglycerides) are glycerides in which the glycerol is esterified with three fatty acids. ... In chemistry, especially biochemistry, a fatty acid is a carboxylic acid (or organic acid), often with a long aliphatic tail (long chains), either saturated or unsaturated. ... In medicine, insulin resistance denotes a decompensation of glucose homeostasis where the tissues appear to be less responsive to insulin. ... Template:In progress The human abdomen (from the Latin word meaning belly) is the part of the body between the pelvis and the thorax. ... Santorio Santorio (1561-1636) in his steelyard balance, from Ars de statica medecina, first published 1614 Metabolism (from μεταβολισμος (metabolismos), the Greek word for change, or overthrow (Etymonline)), is the biochemical modification of chemical compounds in living organisms and cells. ... Central obesity (or apple-shaped or masculine obesity), is when the main deposits of body fat are localised around the abdomen and the upper body. ... Cardiovascular disease refers to the class of diseases that involve the heart and/or blood vessels (arteries and veins). ... Diabetes mellitus is a medical disorder characterized by varying or persistent hyperglycemia (elevated blood sugar levels), especially after eating. ... Hypertension or high blood pressure is a medical condition where the blood pressure in the arteries is chronically elevated. ...

Recent advances in biotechnology have allowed for the harvesting of adult stem cells from adipose tissue, allowing stimulation of tissue regrowth using a patient's own cells. The use of a patient's own cells reduces the chance of tissue rejection and avoids the social trauma associated with the use of human embryonic stem cells. Mouse embryonic stem cells. ...

Hormones secreted by adipose tissue include:

• Adiponectin
• Resistin
• Angiotensin
• Plasminogen activator inhibitor-1 (PAI-1)
• TNFα
• IL-6
• Leptin

A specialised form of adipose tissue in human infants, and some animals, is brown fat or brown adipose tissue. It is located mainly around the neck and large blood vessels of the thorax. This specialised tissue can generate heat by "uncoupling" the respiratory chain of oxidative phosphorylation within mitochondria, leading to the breakdown of fatty acids. This thermogenic process may be vital in neonates exposed to the cold, who then require this thermogenesis to keep warm as they are unable to shiver, or take other actions to keep themselves warm. Adiponectin (also referred to as Acrp30, apM1) is a protein hormone that modulates a number of metabolic processes, including glucose regulation and fatty acid catabolism. ... Resistin is a hormone secreted by adipose tissue. ... Angiotensinogen, angiotensin I and angiotensin II are peptides involved in maintenance of blood volume and pressure. ... Plasminogen activator inhibitor-1 is the principal inhibitor of tissue plasminogen activator (tPA) and urokinase (uPA), the activators of plasminogen and hence fibrinolysis (the physiological breakdown of blood clots). ... In medicine, tumor necrosis factor alpha (TNFα, cachexin or cachectin) is an important cytokine involved in systemic inflammation and the acute phase response. ... Interleukins are a group of cytokines that are expressed by white blood cells (leukocytes, hence the -leukin) as a means of communication (inter-). The function of the immune system depends in a large part on interleukins, and rare deficiencies of a number of them have been described, all featuring autoimmune... Leptin is a protein hormone produced by adipose tissue. ... A human infant. ... Brown fat is a type of adipose tissue present in many newborn or hibernating mammals. ... Brown fat is a type of adipose tissue present in many newborn or hibernating mammals. ... The electron transfer chain (also called the electron transport chain, or simply electron transport), is a series of protein complexers and lipid messengers spanning the inner mitochondrial membrane that accepts electrons from electron donors such as NADH or succinate, shuttles these electrons from within the mitochondrial matrix across the inner... Oxidative phosphorylation is a biochemical process in cells. ... In cell biology, a mitochondrion is an organelle found in the cells of most eukaryotes. ... Shivering is a human bodily function in response to cold. ...

Attempts to stimulate this process pharmacologically have so far been unsuccessful, but might in the future be a target of weight loss therapy. Pharmacology (in Greek: pharmacon (φάρμακον) is drug, and logos (λόγος) is science) is the study of how chemical substances interact with living systems. ... In the context of physical health, weight loss is the process of losing body weight, usually by losing fat. ...

Cultural and social role

In the modern world, excess fatty tissue on a human is often considered an aesthetic and medical problem (see dieting and obesity). In earlier times and other societies, fat was considered aesthetically pleasing. This can be inferred from the depiction of characters who by modern standards would be considered obese, in paintings by Rembrandt and especially Peter Paul Rubens. The latter's characters inspired the term Rubenesque as a positive (if sometimes jocular) reference to a woman with notable amounts of body fat. Dieting is the practice or habit of eating (and drinking) in a regulated fashion, usually with the aim of losing weight. ... Rembrandt Harmenszoon van Rijn (July 15, 1606 – October 4, 1669) is generally considered one of the greatest painters in European art history (together with Pieter Paul Rubens), and the most important United Provinces (Netherlands) painter of the seventeenth century. ... Pieter Pauwel (Peter Paul) Rubens (June 28, 1577 – May 30, 1640) is considered one of the greatest painters in European art history (together with Dutchman Rembrandt van Rijn), and the most important Flemish (Netherlands, nowadays Belgium) painter of the sixteenth century. ...

In Arab, West African, native Arctic and many Latin American cultures, many men express a preference for sturdy or "well-fed" women. The majority of men from developed nations, East Asia, and many East African cultures show a preference for thin women. The Arabs (Arabic: عرب Ê»arab) are an originally Arabian ethnicity widespread in the Middle East and North Africa. ... West African refers to: West Africa An airline: West African Airlines [1] This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... The red line indicates the 10°C isotherm in July, commonly used to define the Arctic region border The Arctic is the area around the Earths North Pole. ... Latin America consists of the countries of South America and some of North America (including Central America and some the islands of the Caribbean) whose inhabitants mostly speak Romance languages, although Native American languages are also spoken. ... A developed country is a country that has achieved (currently or historically) a high degree of industrialization, and which enjoys the higher standards of living which wealth and technology make possible. ... East Asia can be defined in either cultural or geographic terms. ...

More generally, fat, because of its association with high food energy intake and low physical exertion, may be considered an indication of wealth and privilege as well as gluttony and sloth. Food energy is the amount of energy in food. ...

See also

• Obesity
• Cellulite

Cellulite is the dimpling pattern on skin caused by lobules of underlying adipose tissue. ...