Puerarin suppresses AGEs-induced inflammation in mouse mesangial cells: a possible pathway through the induction of heme oxygenase-1 expression.
Puerarin is a natural product isolated from Puerarin lobata and has various pharmacological effects, including anti-hyperglycemic and anti-allergic properties. In the present study, we investigated the effect of puerarin against advanced glycation end products (AGEs)-induced inflammation in mouse mesangial cells. Puerarin acts by inducing the expression of heme oxygenase-1 (HO-1) in a dose- and time-dependent manner. Puerarin was able to enhance phosphorylation of protein kinase C (PKC) delta, but not PKC alpha/beta II, in a time-dependent manner. Induction of HO-1 expression by puerarin was suppressed by GF109203X, a general inhibitor of PKC, and by rottlerin, a specific inhibitor of PKC delta. However, induction was not suppressed by Gö6976, a selective inhibitor for PKC alpha/beta II. Additionally, the knockdown of endogenous PKC delta by small interfering RNA (siRNA) resulted in the inhibition of HO-1 expression and Akt phosphorylation. Puerarin increased antioxidant response element (ARE)-Luciferase activity in a dose- and time-dependent manner in transfected mouse mesangial cells. Mutation of the ARE sequence abolished puerarin-induced HO-1 expression. Furthermore, puerarin treatments resulted in a marked increase in NF-E2 related factor-2 (Nrf-2) translocation, leading to up-regulation of HO-1 expression. However, transfection of Nrf-2 specific siRNA abolished HO-1 expression. Pretreatment with puerarin inhibited the expressions of COX-2, MMP-2 and MMP-9. But, these effects were reversed by ZnPP, an inhibitor of HO-1. Taken together, our results demonstrate that puerarin-induced expression of HO-1 is mediated by the PKC delta-Nrf-2-HO-1 pathway and inhibits N-carboxymethyllysine (CML)-induced inflammation in mouse mesangial cells.
Kim
Ki Mo
KM
Diabetic Complications Research Center, Division of Traditional Korean Medicine (TKM) Integrated Research, Korea Institute of Oriental Medicine (KIOM), 483 Exporo, Yuseong-gu, Daejeon 305-811, South Korea.
Jung
Dong Ho
DH
Jang
Dae Sik
DS
Kim
Young Sook
YS
Kim
Jong Min
JM
Kim
Ha-Na
HN
Surh
Young-Joon
YJ
Kim
Jin Sook
JS
D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D004790:Enzyme Induction / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D055785:Gene Knockdown Techniques; D017127:Glycation End Products, Advanced / Q000037:antagonists & inhibitors* / Q000502:physiology; D051547:Heme Oxygenase-1 / Q000096:biosynthesis* / Q000235:genetics; D007249:Inflammation / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D007529:Isoflavones / Q000494:pharmacology*; D050527:Mesangial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D051379:Mice; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics / Q000502:physiology*
D000894:Anti-Inflammatory Agents, Non-Steroidal; D017127:Glycation End Products, Advanced; D007529:Isoflavones; D051547:Heme Oxygenase-1; C033607:puerarin