Description

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Picture Courtesy: THE HINDU

Context

Scientists at the Indian Institute of Science (IISc) in Bengaluru have engineered an artificial metal-based nanozyme.

About Blood Clotting

Under normal circumstances, blood clotting, or haemostasis, is a vital protective mechanism. When a blood vessel is injured, specialized blood cells called platelets are activated. They cluster around the injury site, forming a clot to stop bleeding. This process involves a complex series of protein interactions triggered by signals from physiological agonists like collagen and thrombin.

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In certain conditions like COVID-19, these signaling pathways can malfunction. This leads to increased oxidative stress and elevated levels of toxic Reactive Oxygen Species (ROS). The surge in ROS causes over-activation of platelets, triggering the formation of excessive clots within blood vessels, known as thrombosis, which is a major contributor to morbidity and mortality

Nanozyme Solution

The IISc team developed nanomaterials that mimic the activity of natural antioxidant enzymes. These "nanozymes" work by controlling the levels of ROS, thereby preventing the over-activation of platelets that leads to thrombosis.

Nanozymes are nanomaterials that possess enzyme-like characteristics. This means they can act as catalysts for biochemical reactions, much like natural enzymes found in living organisms.

The researchers isolated platelets from human blood, activated them using physiological agonists (chemicals that trigger clotting), and then tested the effectiveness of different nanozymes in preventing excess platelet aggregation.

The team discovered that spherical-shaped vanadium pentoxide (V2O5) nanozymes were the most efficient. The nanozyme was tested on human blood platelets in the laboratory, where it successfully prevented excessive clot formation.

Source:

THE HINDU

PRACTICE QUESTION

Q. Consider the following statements:

Under normal circumstances, platelets aggregate around injured blood vessels to form protective clots.
Pulmonary thromboembolism (PTE) is a condition characterised by under-activation of platelets.
Thrombosis caused by excess clot formation.

How many of the above statements are correct?

A) Only one

B) Only two

C) All three

D) None

Answer: B

Explanation:

Statement 1 is correct. Under normal circumstances, when a blood vessel is injured, specialised blood cells called platelets get activated, and cluster together around the vessel to form protective blood clots. This process is known as the blood clotting cascade (haemostasis).

Statement 2 is incorrect: Pulmonary thromboembolism (PTE) is a blockage of an artery in the lungs, usually by a blood clot that has traveled from elsewhere in the body (often the legs). Platelet activation is a key event in the formation of these clots (thrombosis). Increased platelet activity associated with PE.

Statement 3 is correct: Thrombosis is the formation of a blood clot (thrombus) inside a blood vessel, which can obstruct blood flow. It is essentially a condition of excessive or inappropriate clotting.