Biological activity of 9-PAHSA enantiomers R- and S-9-PAHSA. A: Insulin secretion from clonal pancreatic MIN6 β-cells: MIN6 cells were incubated with DMSO (control) or racemic, R-9-PAHSA or S-9-PAHSA (20 μM) for 1 h and stimulated with low (2.5 mM) or high (20 mM) glucose for 45 min. n = 8 wells/condition. Each isomer was tested in two independent studies. Data are the means ± SEM. ∗P < 0.05 versus high glucose DMSO by one-way ANOVA. B: GSIS from isolated human islets from donor 3. n = 50 islets/well and three wells per each condition. ∗P < 0.05 versus high glucose DMSO, #P < 0.05 versus high glucose R-9-PAHSA by one-way ANOVA. C: Calcium flux assay in mGPR40 stably transfected cells treated with the control buffer, 9-PAHSA, R-9-PAHSA, and S-9-PAHSA. n = 4/condition. Data are the means ± SEM. ∗P < 0.05 versus buffer by one-way ANOVA. D: Basal and insulin-stimulated glucose transport in 3T3L1 adipocytes treated with racemic 9-PAHSA, R-9-PAHSA, S-9-PAHSA (20 μM), or DMSO for 24 h. n = 4–6 wells/condition. ∗P < 0.05 versus DMSO. E, Effects of racemic (Rac) and R- and S-9-PAHSA on LPS-induced Tnf or Il-6 secretion from BMDCs and BMDMs. n = 4–6 wells/condition. Each isomer was tested in two independent studies. Data are the means ± SEM. ∗P < 0.05 versus LPS-induced DMSO by one-way ANOVA. BMDC, bone marrow–derived dendritic cell; BMDM, bone marrow–derived macrophage; GSIS, glucose-stimulated insulin secretion; LPS, lipopolysaccharide; PAHSA, palmitic acid hydroxy stearic acid.