Intestinal Villi – Function, Structure & Diseases
Intestinal villi are finger-like projections of the small intestinal lining that greatly increase the surface area for nutrient absorption, playing a key role in healthy digestion.
Wissenswertes über "Intestinal Villi"
Intestinal villi are finger-like projections of the small intestinal lining that greatly increase the surface area for nutrient absorption, playing a key role in healthy digestion.
What Are Intestinal Villi?
Intestinal villi (Latin: Villi intestinales) are tiny, finger-like projections that extend from the inner lining of the small intestine into the intestinal lumen. Together with even smaller projections called microvilli on the surface of individual intestinal cells, they form the so-called brush border, which expands the total absorptive surface area of the small intestine to approximately 250 square metres.
Structure of Intestinal Villi
Each villus is composed of several distinct structures:
- Epithelium: The outermost layer of specialized intestinal cells called enterocytes, responsible for active nutrient uptake.
- Blood capillaries: Absorbed sugars and amino acids pass directly into the bloodstream.
- Central lacteal (lymph capillary): Transports absorbed fats and fat-soluble vitamins into the lymphatic system.
- Connective tissue and smooth muscle: Provide structural support and enable rhythmic movements that enhance absorption.
Function of Intestinal Villi
The primary function of intestinal villi is the absorption of nutrients from digested food. The following substances are taken up:
- Carbohydrates (as simple sugars such as glucose and fructose)
- Proteins (as amino acids and dipeptides)
- Fats (as fatty acids and glycerol)
- Vitamins, minerals, and trace elements
- Water and electrolytes
In addition to absorption, the intestinal villi play an important role in immune defence: the intestinal lining contains numerous immune cells that identify and combat pathogens entering through food.
Diseases Affecting Intestinal Villi
Villous Atrophy
Villous atrophy refers to the shortening or complete loss of intestinal villi, which dramatically reduces the absorptive surface. This leads to malabsorption – insufficient uptake of nutrients from food. The most common cause is coeliac disease, an autoimmune condition in which gluten (a protein found in wheat, barley, and rye) triggers an immune response that damages the villi.
Other Conditions
- Crohn's disease: A chronic inflammatory bowel disease that can affect the small intestine and damage the villi.
- Infectious enteritis: Certain bacteria and viruses can temporarily impair villous structure.
- Short bowel syndrome: After surgical removal of sections of the small intestine, the available villous surface area for absorption is reduced.
Diagnosis of Villous Changes
Changes to the intestinal villi are typically detected through a small bowel biopsy, obtained during an upper gastrointestinal endoscopy (gastroscopy with advancement of the endoscope into the duodenum). Histological examination of the tissue reveals the degree of villous atrophy, which is classified according to the Marsh classification.
Treatment
Treatment depends on the underlying condition:
- For coeliac disease, a lifelong gluten-free diet is the only effective therapy. The intestinal villi typically regenerate fully after strict dietary adherence.
- For Crohn's disease, anti-inflammatory medications, biologics, and in severe cases surgical intervention are used.
- For infectious causes, villous damage often resolves spontaneously.
References
- Kasper, D.L. et al. (eds.) – Harrison's Principles of Internal Medicine, 21st edition, McGraw-Hill Education (2022).
- Schuppan, D. & Zimmer, K.P. – The Diagnosis and Treatment of Celiac Disease. Deutsches Ärzteblatt International, 110(49): 835–846 (2013).
- World Gastroenterology Organisation (WGO) – Global Guidelines: Celiac Disease. WGO (2016). Available at: https://www.worldgastroenterology.org
Verwandte Produkte
For Healthy Oral Flora & Dental Care
Formulated lozenges with Dentalac®, probiotic lactic acid bacteria, and Lactoferrin CLN®
For your universal protection
As one of the most valuable proteins in the body, lactoferrin is a natural component of the immune system.
For your iron balance
Specially formulated for your iron balance with plant-based curry leaf iron, Lactoferrin CLN®, and natural Vitamin C from rose hips.
Best-selling products
For your universal protection
As one of the most valuable proteins in the body, lactoferrin is a natural component of the immune system.
For your iron balance
Specially formulated for your iron balance with plant-based curry leaf iron, Lactoferrin CLN®, and natural Vitamin C from rose hips.
For Healthy Oral Flora & Dental Care
Formulated lozenges with Dentalac®, probiotic lactic acid bacteria, and Lactoferrin CLN®The latest entries
3 Posts in this encyclopedia categoryVascular Neogenesis
Renal Cell Damage
Lymphocyte Function
Most read entries
3 Posts in this encyclopedia categoryMagnesiumcarbonat
Cologne list
Calorie content
Related search terms: Intestinal villi + Villi intestinales + Intestinal villus + Gut villi