Leukotriene C4

Leukotriene C4 (LTC4) is a eicosanoid and a member of the leukotriene family. It is a potent bioactive molecule involved in the regulation of immune responses and inflammation. LTC4 is produced by a variety of cells, including neutrophils, eosinophils, and mast cells, and plays a crucial role in various pathophysiological conditions.

Structure and Synthesis

LTC4 is a cysteinyl leukotriene, characterized by a cysteine residue in its structure. It is synthesized from arachidonic acid through the lipoxygenase pathway. The enzyme 5-lipoxygenase converts arachidonic acid to 5-hydroperoxyeicosatetraenoic acid (5-HPETE), which is then converted to leukotriene A4 (LTA4). LTA4 is further converted to LTC4 by the enzyme LTC4 synthase.

Function

LTC4 is a potent vasoconstrictor and bronchoconstrictor, and it increases vascular permeability. It is involved in the pathogenesis of asthma and allergic reactions, and it contributes to the symptoms of these conditions. LTC4 also plays a role in the regulation of immune cell migration and activation.

Clinical Significance

Inhibitors of LTC4 synthesis or action, such as leukotriene receptor antagonists and 5-lipoxygenase inhibitors, are used in the treatment of asthma and other inflammatory conditions. Measurement of LTC4 levels in biological fluids can be used as a marker of inflammation and immune activation.

See Also

• Leukotriene
• Eicosanoid
• Arachidonic acid
• 5-lipoxygenase
• Leukotriene receptor antagonist