Mk1903

All agonists, drugs and inhibitors were dissolved in glycerol, DMSO or water. Sodium salt of SCFAs were from Sigma and used in a range of concentrations from 0.5 to 8 mM. GPRs agonists: GPR41: 4-CMTB (1 μM Tocris) and Tiglic acid (1–10 mM Sigma); GPR43: AR420626 (1 μM Cayman) and 1-MCPC (1mM Sigma); GPR109a: Niacine (1–10 mM, Sigma) and MK1903 (1 μM Tocris). GPRs sub-unit inhibitors used were: Pertussis toxin (Ptx 0.2 μg/ml) and U73122 (10 μM) from Sigma. HDAC inhibitors: Trichostatin A (TSA 1 μM Sigma), SAHA (5 μM Sigma) and valproic acid (VPA 5 mM Sigma). SP1 inhibitor Mithramycin A (0.1 μM Sigma). PPARγ activators: Pioglitazone (5 μM), Roziglitazone (10 μM) and PPARγ inhibitor G9662 (100 μM), from Cayman. NF-kB inhibitor BAY 11-7082 (40 μM). AP-1 inhibitor SR-11302 (10 μM Tocris). STAT3/Jak2 inhibitor Cucurbitacin I (1 μM) from Tocris. IFNγ (100 U/ml) and TNFα (10 ng/ml) were from Peprotech. Final concentration of DMSO had no detectable effect on cells viability or responses.

All agonists, antagonists and drugs tested were dissolved in a proper vehicle (DMSO, glycerol, water, PBS or ethanol) following the manufacturer’s recommendations. The final concentration used for vehicles had not detectable effect on metabolic activity of the cells. Sodium salts of tested SCFAs were from Sigma and used in a range of concentration from 0.125 to 8 mM (20 mM for acetate). AhR agonist: 2,3,7,8-Tetrachlorodibenzodioxin (TCDD 10 nM, Sigma). GPRs agonists: GPR41: 4-chloro-α-(1-methylethyl)-N-2-thiazolylbenzeneacetamide (4-CMTB 1 µM, Tocris) and Tiglic acid (1 mM, Sigma); GPR43: N-(2,5-Dichlorophenyl)-4-(furan-2-yl)-2-methyl-5-oxo-1,4,5,6,7,8-hexahydro-quinoline-3-carboxamide (AR420626 1 µM, Cayman) and 1-methylcyclopropane carboxylate (MCPC 1 mM, Sigma); GPR109a: Niacine (1 mM, Sigma) and (4aR, 5aR)-4,4a,5,5a-Tetrahydro-1H-cyclopropa[4,5]cyclopenta[1,2]pyrazole-3-carboxylic acid (MK1903 1 µM, Tocris). Pertussis toxin (Ptx at 0.2 µg/mL, Sigma) was used as Gα_i-subunit inhibitor. MCT1 inhibitor used was p-Chloromercuribenzoate acid (pCMB 100 μM, Sigma). HDAC inhibitors: Trichostatin A (TSA 0.1 and 1 µM, Sigma), vorinostat (SAHA 5 µM, Sigma) and valproic acid (VPA 5 mM, Sigma). AhR antagonists: CH-22319 (1 µM, Millipore/Calbiochem), GNF-351 (1 µM, Millipore/Calbiochem), (−)Epigallocathechin gallate (20 µM, EGCG, Sigma).