Haley S, Gulliver K, Baldassarre R, Miller S, Lane R H, Moyer-Mileur L J
Center for Pediatric Nutrition Research, University of Utah, Salt Lake City, UT, USA.
J Musculoskelet Neuronal Interact. 2013 Jun;13(2):157-65.
Preterm infants are born with low bone mineral. Neonatal stress further impedes bone mineralization. Clinical evidence suggests that tactile and kinesthetic stimulation (TKS) improves bone phenotype and decreases stress response. Clinical and translational studies indicate the IGF-1 axis, responsible for postnatal growth and bone mineralization, is a key player. We hypothesized that TKS would attenuate the negative impact of neonatal stress on bone phenotype and the IGF-1 axis in weanling rats.
Neonatal stress (STRESS) or TKS (STRESS + 10min TKS) was administered from D6 to D10. Control animals received standard care. Tissue was harvested on D21. Dual energy x-ray absorptiometry (DXA) and bone morphometry were performed and serum osteocalcin, type I procollagen N-terminal propeptide (PINP), tartrate-resistant acid phosphatase (TRAP), and bone and liver mRNA levels of IGF-1, IGF-1 receptor (IGF-1R), and growth hormone receptor (GHR) were measured.
Neonatal stress increased bone mineral content (BMC), area (BA), growth plate width, liver IGF-1 mRNA, and serum IGF-1. TKS maintained areal bone mineral density (aBMD) and bone specific IGF-1 and IGF-1R mRNA while STRESS decreased compared to controls.
Neonatal stress results in apparent accelerated growth response. TKS differed from STRESS with improved tibia aBMD and increased bone specific IGF-1 mRNA.
早产儿出生时骨矿物质含量较低。新生儿应激会进一步阻碍骨矿化。临床证据表明，触觉和动觉刺激（TKS）可改善骨表型并降低应激反应。临床和转化研究表明，负责出生后生长和骨矿化的胰岛素样生长因子-1（IGF-1）轴是关键因素。我们假设TKS会减轻新生儿应激对断奶大鼠骨表型和IGF-1轴的负面影响。
从出生后第6天至第10天给予新生儿应激（应激组）或TKS（应激 + 10分钟TKS组）。对照动物接受标准护理。在出生后第21天采集组织。进行双能X线吸收法（DXA）和骨形态计量学分析，并测量血清骨钙素、I型前胶原N端前肽（PINP）、抗酒石酸酸性磷酸酶（TRAP）以及骨和肝脏中IGF-1、IGF-1受体（IGF-1R）和生长激素受体（GHR）的mRNA水平。
新生儿应激增加了骨矿物质含量（BMC）、面积（BA）、生长板宽度、肝脏IGF-1 mRNA和血清IGF-1。与对照组相比，TKS维持了骨面积骨密度（aBMD）以及骨特异性IGF-1和IGF-1R mRNA水平，而应激组则下降。
新生儿应激导致明显的生长加速反应。TKS与应激组不同，它改善了胫骨aBMD并增加了骨特异性IGF-1 mRNA水平。
