KN-93 Phosphate

KN-93 phosphate是KN-93的水溶形式.该物质是有效的\选择性的和细胞可透过的CaM激酶II抑制剂(IC50= 0.37 μM,Ki=370 nM)[1].

CaMK II(钙/钙调蛋白依赖性蛋白激酶II)是一种多功能丝氨酸/苏氨酸激酶,在不同的生理系统中具有多种功能.

由于CaMK II可提高细胞增殖,在人类肝星状细胞中,CaMK II抑制剂KN-93可通过调控p53和p21的表达阻断细胞增殖.[2] KN-93可抑制CaMK II的α和β亚基自磷酸化.此外,在PC12h细胞中,KN-93可通过调控TH反应速率,降低Ca2+介导的TH分子磷酸化水平,从而降低多巴胺水平.[1]由于CaMK II对细胞周期进程通过G1期是必需的,KN-93也可在NIH 3T3细胞中诱发G1期细胞周期停滞和细胞凋亡.[3]

在MRL/lpr Foxp3-GFP小鼠中,KN-93可通过抑制脾脏\外周淋巴结和外周血中的CaMK IV,促进Foxp3调节性T细胞产生,同时降低皮肤和肾脏损伤.[4]在大鼠帕金森氏症模型中,纹状体注射KN-93可通过抑制CaMK II活化,减轻左旋多巴诱导的运动障碍.[5]

参考文献：
[1] Sumi M, Kiuchi K, Ishikawa T, Ishii A, Hagiwara M, Nagatsu T, Hidaka H.  The newly synthesized selective Ca2+/calmodulin dependent protein kinase II inhibitor KN-93 reduces dopamine contents in PC12h cells. Biochem Biophys Res Commun. 1991 Dec 31;181(3):968-75.
[2] An P, Zhu JY, Yang Y, Lv P, Tian YH, Chen MK, Luo HS.  KN-93, a specific inhibitor of CaMKII inhibits human hepatic stellate cell proliferation in vitro. World J Gastroenterol. 2007 Mar 7;13(9):1445-8.
[3] Tombes RM, Grant S, Westin EH, Krystal G.  G1 cell cycle arrest and apoptosis are induced in NIH 3T3 cells by KN-93, an inhibitor of CaMK-II (the multifunctional Ca2+/CaM kinase). Cell Growth Differ. 1995 Sep;6(9):1063-70.
[4] Koga T, Mizui M, Yoshida N, Otomo K, Lieberman LA, Crispín JC, Tsokos GC. KN-93, an inhibitor of calcium/calmodulin-dependent protein kinase IV, promotes generation and function of Foxp3 regulatory T cells in MRL/lpr mice. Autoimmunity. 2014 Nov;47(7):445-50.
[5] Yang X, Wu N, Song L, Liu Z.  Intrastriatal injections of KN-93 ameliorates levodopa-induced dyskinesia in a rat model of Parkinson's disease. Neuropsychiatr Dis Treat. 2013;9:1213-20. doi: 10.2147/NDT.S45422.