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.
1 5-SAHSA is a FAHFA in which stearic acid is esterified to 5-hydroxy stearic acid. The levels of SAHSA are moderately elevated in the 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, 5-SAHSA may be a bioactive lipid with roles in metabolic syndrome and inflammation.
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