Department of Physiology, Yonsei University Wonju College of Medicine, Wonju, Korea.
Yonsei Institute of Sports Science and Exercise Medicine, Korea.
Geriatr Gerontol Int. 2017 Nov;17(11):2266-2273. doi: 10.1111/ggi.13030. Epub 2017 Apr 10.
Myokines are peptides released by the skeletal muscle, and have gained popularity as potential biomarkers for sarcopenia. Irisin is a recently identified myokine, but its role in pathological sarcopenia remains unclear. We investigated the validity and accuracy of circulating irisin levels as a potential biomarker for sarcopenia.
We evaluated the anthropometrics, body composition, sarcopenia-related parameters and serum irisin levels of 715 community-dwelling Koreans. Sarcopenia was determined on the basis of the clinical diagnostic criteria of muscle atrophy and weakness, which were proposed by the Asian Working Group for Sarcopenia.
Circulating irisin levels were correlated with appendicular lean mass/height (r = 0.275; r = 0.321) and handgrip strength (r = 0.219; r = 0.312) in both sexes (all P < 0.01). Furthermore, the mean circulating irisin levels were lower in the sarcopenia group than in the normal group (all P < 0.05). In the logistic regression models, the association between serum irisin concentration and incident sarcopenia persisted even after adjusting for potential confounders, such as sex, age and fat indices (odds ratio 0.20, 95% CI 0.07-0.60; P for trend <0.01). The predictive values of serum irisin for sarcopenia were <1.0 μg/mL in men and <1.16 μg/mL in women, with the area under the receiver operating characteristic curves of 0.87 (95% CI 0.77-0.99) and 0.68 (95% CI 0.55-0.81), respectively (all P < 0.01).
A low level of circulating irisin is a sensitive marker for muscle weakness and atrophy. Irisin is a potential biomarker for muscle dysfunction that could help predict the onset of sarcopenia and provide new avenues for monitoring age-related muscle changes. Geriatr Gerontol Int 2017; 17: 2266-2273.
肌因子是由骨骼肌释放的肽类物质，作为肌肉减少症的潜在生物标志物而受到关注。鸢尾素是一种最近被发现的肌因子，但它在病理性肌肉减少症中的作用尚不清楚。我们研究了循环鸢尾素水平作为肌肉减少症潜在生物标志物的有效性和准确性。
我们评估了 715 名居住在社区的韩国人的人体测量学、身体成分、与肌肉减少症相关的参数和血清鸢尾素水平。肌肉减少症是根据亚洲肌肉减少症工作组提出的肌肉萎缩和虚弱的临床诊断标准确定的。
在男女两性中，循环鸢尾素水平与四肢瘦体重/身高（r = 0.275；r = 0.321）和握力（r = 0.219；r = 0.312）相关（均 P < 0.01）。此外，肌肉减少症组的平均循环鸢尾素水平低于正常组（均 P < 0.05）。在逻辑回归模型中，即使在校正性别、年龄和脂肪指数等潜在混杂因素后，血清鸢尾素浓度与发生肌肉减少症之间的关联仍然存在（比值比 0.20，95%置信区间 0.07-0.60；P 趋势 <0.01）。血清鸢尾素对男性肌肉减少症的预测值<1.0 μg/mL，对女性肌肉减少症的预测值<1.16 μg/mL，其受试者工作特征曲线下面积分别为 0.87（95%置信区间 0.77-0.99）和 0.68（95%置信区间 0.55-0.81）（均 P < 0.01）。
低水平的循环鸢尾素是肌肉无力和萎缩的敏感标志物。鸢尾素是肌肉功能障碍的潜在生物标志物，有助于预测肌肉减少症的发生，并为监测与年龄相关的肌肉变化提供新途径。老年医学与老年病学杂志 2017；17：2266-2273。
