Programa de Doctorado en Farmacología, Centro Universitario de Ciencias de la Salud (CUCS), Universidad de Guadalajara, 44340 Guadalajara, Jalisco, Mexico.
Instituto de Terapeutica Experimental y Clínica, CUCS, Universidad de Guadalajara, 44340 Guadalajara, Jalisco, Mexico.
J Immunol Res. 2022 May 10;2022:7258152. doi: 10.1155/2022/7258152. eCollection 2022.
Myostatin is a regulator of muscle size. To date, there have been no published studies focusing on the relation between myostin levels and myopenia in rheumatoid arthritis (RA).
Evaluate the value of serum myostatin as a biomarker of cachexia and low skeletal muscle mass (LSMM) in RA patients, along with whether high serum myostatin is associated to these conditions after adjusting for potential confounders.
This cross-sectional study included 161 female RA patients and 72 female controls. In the RA group, we assessed several potential risk factors for LSMM and rheumatoid cachexia. Dual-energy X-ray absorptiometry was used to quantify the skeletal muscle mass index (SMMI) (considering LSMM ≤ 5.5 kg/m) and the presence of rheumatoid cachexia (a fat-free mass index ≤ 10 percentile and fat mass index ≥ 25 percentile of the reference population). Serum myostatin concentrations were determined by ELISA. To identify a cut-off for high serum myostatin levels, we performed ROC curve analysis. Multivariable logistic regression analysis was used to identify the risk factors for LSMM and rheumatoid cachexia. The risk was expressed as odds ratios (ORs) and their 95% confidence intervals (95% CIs).
Compared to the controls, the RA group had a higher proportion of LSMM and exhibited high serum myostatin levels ( < 0.001). ROC curve analysis showed that a myostatin level ≥ 17 ng/mL was the most efficient cut-off for identifying rheumatoid cachexia (sensitivity: 53%, specificity: 71%) and LSMM (sensitivity: 43%, specificity: 77%). In the multivariable logistic regression, RA with high myostatin levels (≥17 ng/mL) was found to increase the risk of cachexia (OR = 2.79, 95% CI: 1.24-6.29; = 0.01) and LSMM (OR = 3.04, 95% CI: 1.17-7.89; = 0.02).
High serum myostatin levels increase the risk of LSMM and rheumatoid cachexia. We propose that high myostatin levels are useful biomarkers for the identification of patients in risk of rheumatoid cachexia and myopenia.
肌肉生长抑制素是肌肉大小的调节因子。迄今为止，尚无研究关注肌肉生长抑制素水平与类风湿关节炎（RA）患者的肌肉减少症之间的关系。
评估血清肌肉生长抑制素作为 RA 患者恶病质和低骨骼肌量（LSMM）生物标志物的价值，并在调整潜在混杂因素后，确定高血清肌肉生长抑制素是否与这些情况相关。
本横断面研究纳入了 161 名女性 RA 患者和 72 名女性对照者。在 RA 组中，我们评估了 LSMM 和类风湿性恶病质的多个潜在危险因素。双能 X 射线吸收法用于定量骨骼肌量指数（SMMI）（考虑 LSMM ≤ 5.5kg/m）和类风湿性恶病质的存在（无脂肪质量指数≤参考人群的第 10 百分位数和脂肪质量指数≥第 25 百分位数）。通过 ELISA 法测定血清肌肉生长抑制素浓度。为了确定高血清肌肉生长抑制素水平的截断值，我们进行了 ROC 曲线分析。多变量逻辑回归分析用于确定 LSMM 和类风湿性恶病质的危险因素。风险表示为比值比（ORs）及其 95%置信区间（95%CI）。
与对照组相比，RA 组 LSMM 的比例更高，且血清肌肉生长抑制素水平较高（<0.001）。ROC 曲线分析显示，肌肉生长抑制素水平≥17ng/ml 是识别类风湿性恶病质（灵敏度：53%，特异性：71%）和 LSMM（灵敏度：43%，特异性：77%）的最佳截断值。在多变量逻辑回归中，发现高肌肉生长抑制素水平（≥17ng/ml）的 RA 患者患恶病质（OR=2.79，95%CI：1.24-6.29；=0.01）和 LSMM（OR=3.04，95%CI：1.17-7.89；=0.02）的风险增加。
高血清肌肉生长抑制素水平增加 LSMM 和类风湿性恶病质的风险。我们提出，高肌肉生长抑制素水平可作为识别类风湿性恶病质和肌肉减少症高危患者的有用生物标志物。
