Lamellar Bodies

Definition

Lamellar bodies are specialized organelles found within the cells of the stratum granulosum, the granular layer of the epidermis. They are responsible for the production and storage of lipids that are essential for the formation of the skin's protective barrier, known as the stratum corneum.

5 Must Know Facts For Your Next Test

1. Lamellar bodies are disc-shaped organelles that contain a stack of lipid-rich membranes, resembling a stack of coins.
2. They are produced within the cells of the stratum granulosum and migrate towards the cell surface, where they fuse with the cell membrane and release their contents.
3. The lipids secreted from lamellar bodies are essential for the formation and maintenance of the stratum corneum, the skin's outermost protective layer.
4. Disruption in the production or function of lamellar bodies can lead to skin barrier dysfunction, resulting in conditions like atopic dermatitis and ichthyosis.
5. The contents of lamellar bodies, including ceramides, cholesterol, and free fatty acids, are crucial for the skin's water-holding capacity and resistance to environmental stressors.

Review Questions

• Explain the role of lamellar bodies in the formation and maintenance of the skin's protective barrier.
  • Lamellar bodies play a crucial role in the formation and maintenance of the skin's protective barrier, the stratum corneum. They are responsible for producing and storing the essential lipids, such as ceramides, cholesterol, and free fatty acids, that are secreted and organized into the extracellular matrix of the stratum corneum. This lipid-rich layer acts as a barrier, preventing the loss of water and protecting the skin from environmental stressors and pathogens.
• Describe the location and structure of lamellar bodies within the layers of the epidermis.
  • Lamellar bodies are primarily located within the cells of the stratum granulosum, the granular layer of the epidermis. They have a distinctive disc-shaped structure, resembling a stack of coins, and contain a stack of lipid-rich membranes. As the cells of the stratum granulosum differentiate and move towards the skin's surface, the lamellar bodies migrate and fuse with the cell membrane, releasing their contents to contribute to the formation of the stratum corneum.
• Analyze the potential consequences of disruptions in lamellar body function and their impact on skin health.
  • Disruptions in the production, transport, or function of lamellar bodies can lead to significant problems in the skin's barrier function. Without the proper secretion of the lipids stored within lamellar bodies, the stratum corneum may not form properly, resulting in conditions like atopic dermatitis and ichthyosis. These skin disorders are characterized by a compromised skin barrier, leading to increased water loss, susceptibility to environmental irritants, and an increased risk of infection. Understanding the critical role of lamellar bodies in maintaining skin health is essential for developing effective treatments and preventive strategies for these types of skin conditions.

Related terms

Stratum Granulosum:

The granular layer of the epidermis, where lamellar bodies are primarily located and play a crucial role in the skin's barrier function.

Stratum Corneum:

The outermost layer of the epidermis, composed of dead, flattened cells, which is formed and maintained by the lipids secreted from lamellar bodies.

Epidermal Lipids: The lipids, such as ceramides, cholesterol, and free fatty acids, that are produced and stored within lamellar bodies and then secreted to form the skin's protective barrier.