When you purchase through links on our site , we may earn an affiliate charge . Here ’s how it work out .
Scientists say they ’ve identified a young type of cartilage — one that was in reality discovered in the nineteenth century , leave , rediscover and then forgotten again .
Medical schoolbook describe threetypes of gristle : hyaline , elastic and fibrocartilage . Hyaline cartilage help bones slither swimmingly over each other at the joint ; elastic cartilage is very flexible and found in the outside ear , part box , and tube between the auricle and pharynx ; and fibrocartilage is sturdy and absorbs impacts at the joints and in the spine . The cells within these tissues are surrounded by lots ofcollagenand pliant fiber , the proportions of which give each character of cartilage its distinct characteristics .
This is a newly described kind of cartilage, called “lipocartilage.” This image shows tissue from a mouse ear with the bubbles of fat in the cells stained with green dye.
Now , however , scientists say there ’s a quaternary type of cartilage that look very dissimilar from the other form .
The tissue paper , which they call " lipocartilage , " superficially looks a lot like adipose tissue — substantially known as productive . It hold back bulbous , balloon - like cells fill with oils , and the cells are surrounded by a thin intercellular substance of fibers , rather than a fatheaded matrix common to other cartilage . The cells are also highly uniform and can tamp down tight together like bricks . Together , the cubicle organize a springy , squishy tissue that has a chip of give but still resists deformation and tearing ; this tissue is feel in structures like the external ear and nose .
link up : New part of the body found hiding in the lungs
An image of lipocartilage from a mouse ear.
Some experts were impressed with the unexampled analysis of lipocartilage . For example , Viviana Hermosilla AguayoandDr . Licia Selleriof the University of California , San Francisco write in acommentarythat this " long - cut cartilage type " may " guarantee updates to histology and anatomy textbooks . "
Others said that the researcher provided strong evidence of the tissue paper ’s existence but that they are n’t sure lipocartilage merits its own classification .
" The authors provide evidence that this lipid - containing cartilage tissue exists in multiple mammal , including humans,“Shouan Zhu , director of the Osteoarthritis Research Laboratory at Ohio University , who was not call for in the subject , told Live Science in an email . But " what I am not sure [ of ] is if it should be considered as a separate new type of tissue paper or just a new feature of speech of an exist tissue , " namely , elastic cartilage .
What’s old is new again
" This was a serendipitous find , " analyze senior authorMaksim Plikus , a professor in the Department of Developmental and Cell Biology at the University of California , Irvine , told Live Science in an e-mail . The team was canvas the peel of mouse ear when they stumbled upon the fat - binge cartilage cells , which Plikus compares to " Bubble Wrap . "
But when they dug deep , the squad find out their discovery was n’t entirely refreshing . It deform out that other scientist had spotted this unique tissue before , Plikus noted .
In the 1850s , histologist Franz von Leydigwrote about his observations of rats ' ear cartilage under the microscope . " At first sight it appear like adipose tissue , " but it still has a distinct matrix , like cartilage , he noted . Leydig ’s reflexion would descend into obscurity for more than a century . Then , in the sixties , scattered report described similar fatty tissues in rodent ears . In 1976 , a duad of scientists mint the term " lipochondrocyte " for the cells found in lipocartilage . But again , these discovery were soon blank out .
Now , with their study published Thursday ( Jan. 9 ) in the journalScience , Plikus and fellow offer a very close analysis of lipocartilage , give away its stages of ontogeny , hereditary traits and molecular characteristics . The study highlights how the tissue differs from its look - similar — fatness — and how it ’s standardised to other type of cartilage .
In mouse , the team read that the social structure that agree the blubber within lipocartilage are " superstable . " Unlike fat prison cell , which get larger or smaller depending on food intake , lipocartilage cells do n’t recoil in time of starvation or swell in reply to surplus . This stability partly stem from the tissue ’s lack of enzymes for breaking down fat , as well as from a lack of transporters that land fats from food for thought into the tissue paper , the team found .
" This machine characteristic may propose an evolutionary advantage for the ear pinna " — the out ear — " by enhancing its power to gather and focus acoustical waves , " Zhu said . Sound wavesripple through fatness very efficiently , so perhaps maintaining this mellow - fatty tissue gristle in the outside pinna is useful for audience , the authors also suggested .
Since the lipocartilage in the spike is n’t go to swell or shrink look on calorie consumption , the acoustics it supports should also stay firm over clip .
Where is lipocartilage found?
The written report author initially identify lipocartilage in the external ears , nose and throats of mice . " It is in the pinched gristle at the very tip of the nose , " Plikus say . " It forms the intact pinna gristle , " as well as the Brobdingnagian majority of voice box , or voice box , he suppose .
" In all these places , a mellow level of elasticity is required and unlike the body ’s other cartilages , such as joint cartilage , these structures are not weightiness - carriage , " he added . For example , a structure in the throat called theepiglottisflexibly flaps back and forth during swallowing to finish food from getting into the respiratory piece of land .
After studying mice , the researchers also identify lipocartilage in human fetal tissue , namely from the ear , nose , epiglottis and thyroid cartilage , which sits above the thyroid gland . They also found that lipocartilage egress in models of human gristle that they grow from prow cells in the lab .
— Scientists discover unexampled eccentric of cellular telephone in the liver
— Body parts grow in the research laboratory
— scientist take Brobdingnagian measure forrader in make atlas of all 37 trillion cells in the human body
To see how rife lipocartilage is across the animal kingdom , the team examined museum specimens of dozens of species . They spotted the tissue paper in several mammal — such as the Cairo spiny mouse ( Acomys cahirinus ) , squirrel glider ( Petaurus norfolcensis ) and Pallas ’s long - tongued cricket bat ( Glossophaga soricina ) — but did n’t find it in any nonmammals , such as frogs , boo or alligators .
The authors say questions rest about when lipocartilage first come forth and what evolutionary advantages it might declare oneself to the brute it ’s found in . The squad hopes to canvass the tissue ’s development , as well as investigate its power to regenerate after injury and probe whether lipocartilage incorporate unlike subtypes of cells . They also need to better empathize how the cells manage such gamy adipose tissue content , " which can be toxic for many other cell types , " Plikus pronounce .
" We believe these finding of a new cell case and new tissue paper type are primal and paradigm - shifting , " he said of the work so far .
