7-Dehydrodesmosterol

7-Dehydrodesmosterol

7-Dehydrodesmosterol is a sterol intermediate in the biosynthesis of cholesterol. It is a crucial compound in the mevalonate pathway, which is the metabolic pathway that produces isoprenoids, including cholesterol and other sterols. Understanding the role of 7-Dehydrodesmosterol is important for comprehending the complex processes involved in cholesterol synthesis and regulation.

Structure and Properties

7-Dehydrodesmosterol is a sterol with the chemical formula C27H42O. It is characterized by a double bond in the sterol ring structure, which is a common feature in sterol intermediates. The presence of this double bond distinguishes it from other sterols such as desmosterol and cholesterol.

Biosynthesis

7-Dehydrodesmosterol is synthesized from lanosterol through a series of enzymatic reactions. The conversion involves multiple steps, including the removal of methyl groups and the introduction of double bonds. This process is part of the larger mevalonate pathway, which is responsible for the production of cholesterol and other essential sterols.

Biological Role

In the body, 7-Dehydrodesmosterol serves as a precursor to cholesterol. Cholesterol is a vital component of cell membranes, where it modulates fluidity and permeability. It is also a precursor for the synthesis of steroid hormones, bile acids, and vitamin D. The regulation of cholesterol synthesis, including the conversion of 7-Dehydrodesmosterol, is tightly controlled by feedback mechanisms to maintain homeostasis.

Clinical Significance

Abnormalities in the metabolism of 7-Dehydrodesmosterol can lead to disorders in cholesterol synthesis. For example, defects in the enzymes involved in its conversion can result in conditions such as desmosterolosis, a rare genetic disorder characterized by elevated levels of desmosterol and related sterol intermediates. Understanding these pathways is crucial for developing treatments for such metabolic disorders.

Also see

• Cholesterol
• Mevalonate pathway
• Sterol
• Desmosterol
• Lanosterol