Branski Ryan C, Perera Priyangi, Verdolini Katherine, Rosen Clark A, Hebda Patricia A, Agarwal Sudha
Head and Neck Surgery, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
J Voice. 2007 Nov;21(6):651-60. doi: 10.1016/j.jvoice.2006.06.005. Epub 2006 Aug 14.
Despite the fact that vocal folds are subjected to extensive mechanical forces, the role of mechanical strain in vocal fold wound healing has been overlooked. Recent studies on other tissues have demonstrated that low physiological levels of mechanical forces are beneficial to injured tissues, reduce inflammation, and induce synthesis of matrix-associated proteins essential for enhanced wound healing. In this study, we speculated that mechanical strain of low magnitudes also attenuates the production of inflammatory mediators and alters the extracellular matrix synthesis to augment wound healing in cultured vocal fold fibroblasts. To test this hypothesis, fibroblasts from rabbit vocal folds were isolated and exposed to various magnitudes of cyclic tensile strain (CTS) in the presence or absence of interleukin-1beta (IL-1beta). Results suggest that IL-1beta activates proinflammatory gene transcription in vocal fold fibroblasts. Furthermore, CTS abrogates the IL-1beta-induced proinflammatory gene induction in a magnitude-dependent manner. In addition, CTS blocks IL-1beta-mediated inhibition of collagen type I synthesis, and thereby upregulates collagen synthesis in the presence of IL-1beta. These findings are the first to reveal the potential utility of low levels of mechanical signals in vocal fold wound healing, and support the emerging on vivo data suggesting beneficial effects of vocal exercise on acute phonotrauma.
尽管声带受到广泛的机械力作用，但机械应变在声带伤口愈合中的作用一直被忽视。最近对其他组织的研究表明，低生理水平的机械力对受损组织有益，可减轻炎症，并诱导合成增强伤口愈合所必需的基质相关蛋白。在本研究中，我们推测低强度的机械应变也会减弱炎症介质的产生，并改变细胞外基质合成，以促进培养的声带成纤维细胞的伤口愈合。为了验证这一假设，分离了兔声带的成纤维细胞，并在有或没有白细胞介素-1β（IL-1β）的情况下，使其暴露于不同强度的循环拉伸应变（CTS）中。结果表明，IL-1β激活声带成纤维细胞中的促炎基因转录。此外，CTS以强度依赖的方式消除IL-1β诱导的促炎基因诱导。此外，CTS阻断IL-1β介导的I型胶原合成抑制，从而在存在IL-1β的情况下上调胶原合成。这些发现首次揭示了低水平机械信号在声带伤口愈合中的潜在作用，并支持了新出现的体内数据，表明发声锻炼对急性发声创伤有有益作用。
