New Cartilage Type Found: Lipocartilage Resembles Fat, Boosts Elasticity

A newly identified form of cartilage, distinct from the three commonly recognised types, has been described by scientists. This tissue, termed "lipocartilage," stands out due to its unique composition. Unlike typical cartilage, which features thick fibre matrices, lipocartilage contains balloon-like cells filled with oils. These cells are uniform and closely packed, forming a springy yet durable structure. Found in areas such as the ear and nose, this tissue combines elasticity with resistance to deformation, according to reports.

Study Highlights the Characteristics of Lipocartilage

As per findings published in Science, lipocartilage was first observed during an analysis of mouse ear tissue. This tissue, resembling fat but with a distinct fibrous matrix, was shown to maintain its size regardless of calorie intake. Unlike adipose cells, lipocartilage lacks enzymes for fat breakdown and transporters for dietary fats, ensuring its structural stability. Maksim Plikus, Professor at the University of California, Irvine, compared it to "Bubble Wrap" in an email to Live Science, noting its role in enhancing the acoustic properties of the outer ear by maintaining consistent sound wave transmission.

Historical Observations Rediscovered

The tissue was first documented in the 1850s by Franz von Leydig, who described it as cartilage resembling adipose tissue. Subsequent mentions in the 1960s and 1970s faded into obscurity until its recent rediscovery. The study highlights lipocartilage's distinct genetic and molecular characteristics, supporting its classification as a potential fourth type of cartilage. Some experts, including Shouan Zhu from Ohio University, have expressed reservations, suggesting it might represent a subtype of elastic cartilage.

Wider Implications and Future Research

Lipocartilage was identified in human fetal tissues and several mammals but not in nonmammals. Researchers aim to explore its evolutionary origins, regenerative capabilities, and how it manages high fat content without toxicity. As reported by Live Science, according to Viviana Hermosilla Aguayo and Dr. Licia Selleri from the University of California, San Francisco, this discovery may necessitate updates to anatomy and histology texts.