5-oxo-eicosatetraenoic acid

5-Oxo-eicosatetraenoic acid (5-oxo-ETE) is a biologically active lipid derived from arachidonic acid, a polyunsaturated fatty acid. It is part of the eicosanoid family, which includes various signaling molecules that play critical roles in inflammation and immunity.

Biochemistry

5-Oxo-ETE is synthesized from 5-hydroxyeicosatetraenoic acid (5-HETE) through the action of 5-hydroxyeicosanoid dehydrogenase. This conversion involves the oxidation of the hydroxyl group at the 5th carbon position to a keto group, forming the oxo derivative.

Biological Functions

5-Oxo-ETE is known to be a potent chemoattractant for eosinophils, a type of white blood cell involved in allergic reactions and asthma. It binds to a specific G-protein coupled receptor known as OXE receptor or OXER1, which is expressed on eosinophils and other immune cells.

Role in Inflammation

As a mediator of inflammation, 5-oxo-ETE contributes to the recruitment and activation of eosinophils at sites of allergic inflammation. This makes it a potential target for therapeutic intervention in diseases such as asthma, where eosinophilic inflammation is a key feature.

Role in Cancer

Recent studies suggest that 5-oxo-ETE may also play a role in cancer biology. It has been implicated in the proliferation and survival of certain cancer cells, making it a subject of interest for cancer research.

Synthesis and Metabolism

The synthesis of 5-oxo-ETE is tightly regulated within the body. It is rapidly metabolized to inactive forms, ensuring that its actions are localized and transient. The primary pathway for its inactivation involves reduction back to 5-HETE or further oxidation to more polar metabolites that are excreted.

Clinical Implications

Due to its role in eosinophil recruitment and activation, 5-oxo-ETE is a potential target for new anti-inflammatory drugs. Inhibitors of its synthesis or action could provide new treatments for asthma and other eosinophil-related disorders.

Research Directions

Ongoing research is focused on understanding the precise mechanisms by which 5-oxo-ETE influences immune cell behavior and its potential role in other diseases beyond asthma, such as cancer and cardiovascular diseases.

Also see

• Arachidonic acid
• Eicosanoids
• Eosinophils
• Asthma
• Inflammation