Vitamin K: Functions, Mechanism of Action, Deficiency etc

Summary

This video explores vitamin K, a fat-soluble vitamin crucial for synthesizing clotting factors II, VII, IX, and X. It highlights the three types of vitamin K—K1 from plants, K2 from bacteria, and synthetic K3. Daily requirements vary, estimated at 100 micrograms, mainly sourced from green leafy vegetables, eggs, and dairy. The video discusses absorption, storage, and the important role of vitamin K in coagulation. It also covers deficiency risks, particularly in newborns and those on antibiotics, and addresses the toxicity associated with synthetic forms. Overall, vitamin K is vital for maintaining proper blood coagulation and overall health.

Takeaways

• 😀 Vitamin K is a fat-soluble vitamin essential for blood coagulation.
• 🌿 There are three types of vitamin K: K1 (from plants), K2 (from bacteria), and K3 (synthetic).
• 🧬 The daily requirement for vitamin K is about 100 micrograms for an average adult.
• 🥗 Dietary sources of vitamin K include alfalfa, spinach, cabbage, egg yolk, meat, and dairy products.
• 🔬 Vitamin K absorption occurs in the small intestine and requires bile salts for effective uptake.
• ⚗️ Vitamin K is crucial for the synthesis of clotting factors II, VII, IX, and X through a carboxylation reaction.
• 🩸 Deficiency in vitamin K can lead to increased bleeding tendencies and conditions such as bruising and gastrointestinal bleeding.
• 👶 Newborns are particularly susceptible to vitamin K deficiency due to low storage and lack of intestinal flora.
• 💊 Vitamin K can be used as a treatment for warfarin poisoning and in cases of dietary deficiency or malabsorption.
• ⚠️ While natural forms of vitamin K (K1 and K2) are safe, toxicity is associated with synthetic K3, which can cause severe side effects.

Q & A

What are the three types of vitamin K?

The three types of vitamin K are K1 (phylloquinone), K2 (menaquinone), and K3 (menadione). K1 is synthesized by plants, K2 by bacteria, and K3 is a synthetic, water-soluble form.

What is the daily requirement of vitamin K for an average adult?

The estimated daily requirement of vitamin K for an average adult is about 100 micrograms, although it can vary due to synthesis by intestinal bacteria.

What are some dietary sources of vitamin K?

Dietary sources of vitamin K include green leafy vegetables like alfalfa, spinach, cabbage, cauliflower, as well as egg yolk, meat, and dairy products.

How is vitamin K absorbed in the body?

Vitamin K is absorbed mainly in the small intestine, and its absorption requires bile salts from the liver because it is fat-soluble.

What role does vitamin K play in blood coagulation?

Vitamin K is essential for the synthesis of clotting factors II, VII, IX, and X, as it helps carbonylate glutamic acid residues in these factors, allowing them to bind calcium and function properly.

What can cause vitamin K deficiency?

Vitamin K deficiency can occur in newborns, prolonged use of antibiotics, malabsorption conditions (like celiac disease), and liver disease that impairs clotting factor synthesis.

What symptoms are associated with vitamin K deficiency?

Symptoms of vitamin K deficiency include increased bleeding tendencies, bruising, gastrointestinal bleeding, and prolonged bleeding and clotting times.

How is vitamin K used therapeutically?

Vitamin K is used to treat dietary deficiencies, malabsorption issues, as a prophylactic for newborns, and as an antidote for warfarin poisoning.

What is the toxicity profile of vitamin K?

Vitamin K1 and K2 are generally safe, while vitamin K3 can cause toxicity, leading to conditions such as hemolysis, jaundice, and kernicterus, especially in newborns.

Why is vitamin K essential for proteins C and S?

Vitamin K is necessary for the carboxylation of proteins C and S, which are anticoagulants that help regulate blood clotting and prevent excessive coagulation.