The effect of exercise and beta2-adrenergic stimulation on glutathionylation and function of the Na,K-ATPase in human skeletal muscle.
The effect of exercise and beta2-adrenergic stimulation on glutathionylation and function of the Na,K-ATPase in human skeletal muscle.
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DOI：
10.14814/phy2.12515
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发表时间：
2015-08
影响因子：
2.5
通讯作者：
Bangsbo J
中科院分区：
文献类型：
--
作者：
Juel C;Hostrup M;Bangsbo J
在运动过程中，钾和钠穿过骨骼肌膜的位移可引起疲劳，并且部分地由Na，K-ATP酶控制。因此，Na，K-ATP酶的调节对肌肉功能很重要。我们研究了氧化应激（谷胱甘肽化）对Na，K-ATP酶活性的影响。10名男性受试者进行了3次4分钟的次极量运动，然后进行剧烈运动，直到筋疲力尽，有和没有β 2-肾上腺素能刺激与特布他林。肌肉活检从m。静息时（对照样本）和力竭时的股外侧肌。体外谷胱甘肽化以剂量依赖性方式降低（P <0.05）Na，K-ATP酶的最大活性。Na，K-ATP酶α亚基通过免疫沉淀纯化并通过谷胱甘肽（GSH）抗体检测，在对照样品中具有基础谷胱甘肽化，并且在运动和β 2-肾上腺素能刺激下没有进一步的谷胱甘肽化。用抗GSH抗体进行免疫沉淀，随后用β 1抗体进行免疫检测，结果显示对照组样本中谷胱甘肽化约为20%，运动后谷胱甘肽化进一步增加（至32%），β 2-肾上腺素能刺激后谷胱甘肽化进一步增加（至38%，P <0.05）。结合运动和β 2肾上腺素能刺激使β 1谷胱甘肽化水平提高到45%（P <0.05）。总之，对照样品中Na，K-ATP酶的α和β 1亚基均被谷胱甘肽化，这表明如果仅基于蛋白质密度，则高估了最大Na，K-ATP酶活性。β 1亚基通过运动和β 2肾上腺素能刺激进一步谷胱甘肽化。我们的数据表明，谷胱甘肽化有助于在人类骨骼肌Na，K-ATP酶功能的复杂调节。Na，K-ATP酶的谷胱甘肽化可能解释了运动后Na，K-ATP酶最大活性的降低，这可能与肌肉疲劳有关。
Potassium and sodium displacements across the skeletal muscle membrane during exercise may cause fatigue and are in part controlled by the Na,K-ATPase. Regulation of the Na,K-ATPase is therefore important for muscle functioning. We investigated the effect of oxidative stress (glutathionylation) on Na,K-ATPase activity. Ten male subjects performed three bouts of 4-min submaximal exercise followed by intense exercise to exhaustion with and without beta2-adrenergic stimulation with terbutaline. Muscle biopsies were obtained from m. vastus lateralis at rest (Control samples) and at exhaustion. In vitro glutathionylation reduced (P < 0.05) maximal Na,K-ATPase activity in a dose-dependent manner. Na,K-ATPase α subunits, purified by immunoprecipitation and tested by glutathione (GSH) antibodies, had a basal glutathionylation in Control samples and no further glutathionylation with exercise and beta2-adrenergic stimulation. Immunoprecipitation with an anti-GSH antibody and subsequent immunodetection with β1 antibodies showed approximately 20% glutathionylation in Control samples and further glutathionylation after exercise (to 32%) and beta2-adrenergic stimulation (to 38%, P < 0.05). Combining exercise and beta2-adrenergic stimulation raised the β1 glutathionylation to 45% (P < 0.05). In conclusion, both α and β1 subunits of the Na,K-ATPase were glutathionylated in Control samples, which indicates that the maximal Na,K-ATPase activity is overestimated if based on protein density only. β1 subunits are further glutathionylated by exercise and beta2-adrenergic stimulation. Our data suggest that glutathionylation contributes to the complex regulation of Na,K-ATPase function in human skeletal muscle. Glutathionylation of the Na,K-ATPase may explain reductions in maximal Na,K-ATPase activity after exercise, which may be involved in muscle fatigue.