Chiarito Mariangela, Farella Ilaria, Lattanzio Crescenza, Vitale Rossella, Urbano Flavia, Guida Pietro, Piacente Laura, Muggeo Paola, Faienza Maria Felicia
Giovanni XXIII Pediatric Hospital, University of Bari "A. Moro", 70124 Bari, Italy.
Department of Medicine and Surgery, LUM University, 70010 Casamassima, Italy.
Genes (Basel). 2025 May 30;16(6):668. doi: 10.3390/genes16060668.
Noonan syndrome (NS) is a genetic disorder characterized by distinctive craniofacial and skeletal features, short stature, mild to moderate developmental impairment, and multisystem involvement, notably affecting the cardiovascular, musculoskeletal, and endocrine systems. Although abnormalities of the bone matrix, as well as osteopenia and osteoporosis, are well recognized in individuals with NS and other RASopathies, the specific impact of RAS/MAPK pathway dysregulation on bone health remains poorly understood. The aim of this study was to evaluate bone turnover and bone remodeling markers in a cohort of children with NS, to gain further insights into the bone status of these patients. In this cross-sectional, case-control study, we analyzed 28 children (20 males) with a molecular diagnosis of NS and 35 healthy subjects (21 males), matched by age and sex. We assessed markers of bone metabolism and bone turnover (calcium, phosphate, PTH, 25(OH)-vitamin D, osteocalcin, procollagen I N-propeptide-P1NP, bone alkaline phosphatase-BALP, C-telopeptides of type I collagen-CTX) and bone remodeling (RANKL, OPG, and sclerostin). Bone mineralization was measured at the lumbar spine (L2-L4) using dual-energy X-ray absorptiometry (DEXA). Serum CTX levels were significantly higher in NS patients compared to controls (1.8 ± 0.7 vs. 1.3 ± 0.5 ng/mL, = 0.0004). RANKL levels were higher in NS patients, although the difference did not reach statistical significance. No significant differences were found for OPG, sclerostin, or other markers of bone metabolism between patients and controls. Children with NS exhibit increased bone resorption, as indicated by elevated CTX levels, suggesting a potential imbalance in bone remodeling processes. Further studies are warranted to better define the impact of RAS/MAPK pathway dysregulation on bone health in this population.
努南综合征(NS)是一种遗传性疾病,其特征为独特的颅面和骨骼特征、身材矮小、轻度至中度发育障碍以及多系统受累,尤其影响心血管、肌肉骨骼和内分泌系统。尽管在患有NS和其他RAS病的个体中,骨基质异常以及骨质减少和骨质疏松已得到充分认识,但RAS/MAPK信号通路失调对骨骼健康的具体影响仍知之甚少。本研究的目的是评估一组NS患儿的骨转换和骨重塑标志物,以进一步了解这些患者的骨骼状况。在这项横断面病例对照研究中,我们分析了28名经分子诊断为NS的儿童(20名男性)和35名健康受试者(21名男性),两组在年龄和性别上相匹配。我们评估了骨代谢和骨转换标志物(钙、磷、甲状旁腺激素、25(OH)-维生素D、骨钙素、I型前胶原N端前肽-P1NP、骨碱性磷酸酶-BALP、I型胶原C端肽-CTX)以及骨重塑标志物(核因子κB受体活化因子配体RANKL、骨保护素OPG和硬化蛋白)。使用双能X线吸收法(DEXA)测量腰椎(L2-L4)的骨矿化。与对照组相比,NS患者的血清CTX水平显著更高(1.8±0.7 vs. 1.3±0.5 ng/mL,P = 0.0004)。NS患者的RANKL水平较高,尽管差异未达到统计学意义。患者和对照组之间在OPG、硬化蛋白或其他骨代谢标志物方面未发现显著差异。NS患儿表现出骨吸收增加,CTX水平升高表明骨重塑过程可能存在失衡。有必要进一步研究以更好地确定RAS/MAPK信号通路失调对该人群骨骼健康的影响。