Hydrocoisone acts as an anti-inflammatory agent because of induction of the synthesis of which of the following protein?
**Core Concept**
Hydrocortisone, a corticosteroid, exerts its anti-inflammatory effects by modulating gene expression and protein synthesis in various cell types, particularly immune cells. This process involves the activation of transcription factors that regulate the expression of specific proteins involved in inflammation.
**Why the Correct Answer is Right**
The correct answer is **Lipocortin 1** (also known as annexin 1). Hydrocortisone induces the synthesis of lipocortin 1, which is a potent inhibitor of phospholipase A2 (PLA2), a key enzyme in the production of prostaglandins and leukotrienes, mediators of inflammation. By inhibiting PLA2, lipocortin 1 reduces the synthesis of these pro-inflammatory eicosanoids, thereby exerting anti-inflammatory effects.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because **Glucocorticoid receptor** is a transcription factor that hydrocortisone binds to, but it is not the protein that is directly responsible for the anti-inflammatory effects.
**Option B:** This option is incorrect because **Cyclooxygenase-2 (COX-2)** is an enzyme involved in the production of prostaglandins, but hydrocortisone actually reduces the expression of COX-2, not induces its synthesis.
**Option D:** This option is incorrect because **Tumor necrosis factor-alpha (TNF-alpha)** is a pro-inflammatory cytokine, and hydrocortisone actually reduces its expression, not induces its synthesis.
**Clinical Pearl / High-Yield Fact**
Corticosteroids like hydrocortisone exert their anti-inflammatory effects by inducing the synthesis of lipocortin 1, which inhibits phospholipase A2 and reduces the production of pro-inflammatory eicosanoids. This mechanism is essential for their therapeutic use in various inflammatory and autoimmune conditions.
**Correct Answer:** C. Lipocortin 1