日本薬理学会年会要旨集
Online ISSN : 2435-4953
WCP2018 (The 18th World Congress of Basic and Clinical Pharmacology)
セッションID: WCP2018_OR9-5
会議情報

Oral session
Redox Signal-mediated TRPM2 promotes adipocyte insulin resistance via Ca2+-dependent CaMKII/JNK cascade in hypertension
Min GaoJingwen XieJing XueYiting WangLi QinXiaoyan Li
著者情報
会議録・要旨集 オープンアクセス

詳細
抄録

Background: Redox-sensitive transient receptor potential melastatin 2 (TRPM2) is a Ca2+-permeable, nonselective cation channel which plays a crucial role in various physiological processes. However, little is known whether TRPM2 is involved in adipocyte dysfunction during hypertension. In the present study, we determined the role of TRPM2 in angiotensin II (Ang II)-induced insulin resistance in adipocytes and the underlying mechanisms.

Methods: Ang II-induced adipocyte insulin resistant model was conducted. Data from Ang II-induced hypertensive mice were used to measure the effects of TRPM2 inhibitor on insulin resistance in vivo. Whole-cell patch clamp technique, intracellular Ca2+ concentration measurement, glucose uptake assay, western blot, cDNA and siRNA transfection were employed to investigate the TRPM2/Ca2+/CaMKII/JNK signaling.

Results: Ang II rose a cation current similar to that activated by hydrogen peroxide (H2O2) or ADP-ribose (ADPR), which was blocked by TRPM2 inhibitor or TRPM2 siRNA in adipocytes. Knockdown of TRPM2 significantly improved the lowered insulin sensitivity induced by Ang II, including insulin stimulated glucose uptake, phosphorylation of IRS1 and Akt, interaction between IR and IRS1 and the membrane translocation of GLUT4, whereas overexpression of TRPM2 resulted in the opposite effects. These results were related to the potentiated effects of TRPM2 on Ca2+ influx and CaMKII/JNK cascade activation upon Ang II induced challenge. Notably, the pharmacological TRPM2 inhibitor, N-(p-amylcinnamoyl)anthranilic acid (ACA), was proved to improve insulin sensitivity in adipose tissue during Ang II-induced hypertension progress.

Conclusions: These data suggested that TRPM2 is a positive regulator of Ang II-induced adipocyte insulin resistance via Ca2+/CaMKII/JNK-dependent signaling pathway. Targeting TRPM2 may be a novel therapeutic strategy to treat hypertension-associated insulin resistance.

著者関連情報
© 2018 The Authors(s)
前の記事 次の記事
feedback
Top