GPR109A promotes Nrf2 nuclear import to exert anti-inflammatory effect by phosphorylating AMPK. (a, b) Protein levels of T-Nrf2, C-Nrf2, HO-1 and N-Nrf2. (c) Immunofluorescence results of Nrf2 nuclear import after treating with niacin for 24 hours. (d, e) The levels of N-Nrf2 and T-Nrf2. (f) Immunofluorescence results of Nrf2 nuclear import after knocking down GPR109A. (g, h) The levels of N-Nrf2 and T-Nrf2. (i) Immunofluorescence results of Nrf2 nuclear import after treating with niacin, CC or niacin+CC for 24 hours. (j, k) Protein levels of T-Nrf2, HO-1 and N-Nrf2. (l) Immunofluorescence results of Nrf2 nuclear import after treating with LPS, niacin or niacin+LPS for 24 hours. Values are presented as means ± SD (n = 3) (*p<0.05, **p<0.01, ***p<0.001, ****p<0.0001).