Beta-sitosterol

Beta-sitosterol is a naturally occurring **phytosterol** (plant sterol) with a structure similar to cholesterol and is widely distributed in fruits, vegetables, nuts, and seeds[3][6]. Chemically, it is known as stigmast-5-en-3β-ol, C29H50O, with a molecular weight of about 414.7 g/mol[1][6]. Beta-sitosterol is not a classical drug target such as a receptor, enzyme, or transporter, but rather a **bioactive plant molecule** with various pharmacological effects. It is used primarily for **lowering cholesterol**, **regulating prostate health (BPH)**, and has demonstrated potential **anticancer, anti-inflammatory, and immunomodulatory properties** in preclinical studies[1][3][5][7][9]. Mechanistically, it limits cholesterol absorption in the intestine, can arrest cancer cell growth by inducing cell cycle arrest and promoting apoptosis, and may regulate oxidative stress and immune responses[2][5][9]. While generally regarded as safe in foods, its role is more as a nutraceutical or dietary supplement and not as a direct molecular therapeutic target. Key notes: - **Beta-sitosterol is not a receptor, enzyme, transporter, or other canonical therapeutic target protein/molecule**. - It is frequently listed as an "active ingredient," not a drug target. - The field sometimes lists phytosterols as "targets," but here the correct categorization is as a **bioactive, non-target molecule**. - is_incorrect = true reflects that this is not a conventional therapeutic target such as a receptor or protein.

Other names

β-sitosterolStigmast-5-en-3β-olStigmast-5-en-3-ol24α-ethylcholesterol(24R)-ethylcholest-5-en-3β-olSitosterolβ-SitosterinAngelicinCincholCupreolQuebracholRhamnolTriastonalΔ5-Stigmasten-3β-ol5-Cholesten-24β-ethyl-3β-ol(24R)-Stigmast-5-en-3β-olAzuprostatNimbosterolNSC 18173NSC 8096ProstasalPhytosterol[6][10]

- Inhibits intestinal absorption of dietary cholesterol - Induces cell cycle arrest (often at G2/M phase) - Activates apoptotic pathways (e.g., caspase activation, increased Bax/Bcl-2 ratio) - Modulates oxidative stress and immune response pathways[2][5][9]