Branched fatty acid esters of hydroxy fatty acids (FAHFAs) are newly identified endogenous lipids regulated by fasting and high-fat feeding and associated with insulin sensitivity in mice.
1 Structurally, these esters are comprised of a C-16 or C-18 fatty acid (
e.g., palmitoleic, palmitic, oleic, or stearic acid) linked to either a C-16 or C-18 hydroxy substituent. 9-POHSA is a FAHFA consisting of palmitoleic acid esterified at the 9-position of hydroxy stearic acid. The levels of POHSA are significantly elevated in serum of glucose tolerant AG4OX mice, which overexpress the Glut4 glucose transporter specifically in adipose tissue.
1 As other FAHFAs improve glucose tolerance, stimulate insulin secretion, and have anti-inflammatory effects, 9-POHSA may be a bioactive lipid with roles in metabolic syndrome and inflammation.
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