Cyklooxygenázy

Cyklooxygenázy, often abbreviated as COX, are a family of enzymes crucial for the synthesis of prostaglandins. These enzymes catalyze the conversion of arachidonic acid into prostaglandin G2 (PGG2), which is then further processed into various other prostaglandins, prostacyclin, and thromboxanes. These lipid mediators play vital roles in a wide range of physiological processes including inflammation, pain sensation, fever, blood clotting, and the protection of the gastric mucosa.

There are at least two main isoforms of cyclooxygenase: COX-1 and COX-2. COX-1 is constitutively expressed in most tissues and is responsible for producing prostaglandins that are involved in normal physiological functions such as protecting the stomach lining and maintaining kidney function. COX-2, on the other hand, is typically induced at sites of inflammation by cytokines and other inflammatory mediators. Its activity leads to the production of prostaglandins that contribute to pain, fever, and swelling.

Inhibition of cyclooxygenases is the primary mechanism of action for nonsteroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen, and naproxen. By blocking COX activity, these drugs reduce prostaglandin production, thereby alleviating pain, fever, and inflammation. However, non-selective NSAIDs that inhibit both COX-1 and COX-2 can lead to side effects, particularly gastrointestinal issues, due to the inhibition of protective prostaglandins produced by COX-1. This has led to the development of selective COX-2 inhibitors, which aim to reduce inflammation without significantly affecting COX-1-mediated protective functions.