Prostaglandin

Context

Prostaglandins were first isolated from prostate tissue (hence the name), but they are produced by virtually all cell types throughout the body. They are short-lived locally acting mediators that regulate not only inflammation but also platelet aggregation, gastric mucosa protection, and renal blood flow.

The prostaglandin family is large. The most relevant in joint inflammation is PGE2 (prostaglandin E2), produced primarily through COX-2 induction in inflamed tissue. Other clinically relevant prostaglandins include prostacyclin (PGI2, a vasodilator) and thromboxane A2 (TXA2, involved in platelet aggregation).

Why it matters for joint health

Prostaglandins are the molecular targets of NSAIDs (non-steroidal anti-inflammatory drugs). NSAIDs work by inhibiting COX enzymes, reducing prostaglandin production, and therefore reducing the acute pain signal. This is why NSAIDs work fast: they intervene at the terminal arm of the inflammatory cascade. The trade-off is that COX-1 inhibition compromises gastric mucosa and renal regulation, which is why long-term daily NSAID use carries documented risks. Modulators that act on different inflammatory arms (like AKBA on the 5-LOX/leukotriene pathway, or curcumin on NF-kB transcription) bypass the prostaglandin pathway entirely.