Department of Burn and Plastic Surgery, Department of Wound Repair, Shenzhen Institute of Translational Medicine, the First Affiliated Hospital of Shenzhen University, Shenzhen, China.
Human Histology & Embryology Section, Department of Surgery, Dentistry, Pediatrics & Gynecology, University of Verona Medical School, Verona, Italy.
Int Wound J. 2023 Aug;20(6):2169-2180. doi: 10.1111/iwj.14095. Epub 2023 Feb 6.
Pressure therapy has been used for the prevention and treatment of hypertrophic scars for decades. However, the cellular and molecular mechanisms of this treatment modality have not been fully elaborated, leading to long-lasting controversies regarding its clinical effectiveness. In this current study, we adopted an in vitro 3D culture and compression model to explore the effect of pressure force on fibroblasts, in order to further explain the working mechanism of compression force during pressure treatment. Human dermal fibroblasts were cultured in the 3D culture hydrogel and treated with 1.5 atm of external compression force through a syringe tube device, for 4, 8, and 20 h respectively. RNA-seq identified 437 differentially regulated genes after an 8-h compression intervention compared with control cells, among which 256 genes were up-regulated and 181 genes were down-regulated. Further q-PCR analysis confirmed that early growth response 1(EGR1) and c-fos were down-regulated after an 8-h compression intervention. However, the down-regulation of EGR1 and c-fos at the mRNA level does not lead to altered protein synthesis through western blot, for both 8 and 20-h time points after pressure intervention. Genes closely related to the fibrotic function of fibroblasts including type I collagen (COL1), type III collagen (COL3), transforming growth factor β1(TGF-β1), matrix metallopeptidase 1 (MMP1), matrix metallopeptidase 1 (TIMP1), connective tissue growth factor (CTGF), α smooth muscle actin (α-SMA), and fibronectin 1 (FN1), were also unaffected after pressure treatment for 8 h. The current study indicated that in our 3D hydrogel culture model, pressure does not directly affect the fibrotic function of dermal fibroblast in vitro. Indirect regulation including reducing oedema, blood perfusion, and tension could be a more possible mechanism of pressure therapy.
压力疗法已被用于预防和治疗肥厚性瘢痕数十年。然而，这种治疗方式的细胞和分子机制尚未完全阐明，导致其临床疗效存在长期争议。在本研究中，我们采用体外 3D 培养和压缩模型来探索压力对成纤维细胞的影响，以进一步解释压力治疗过程中压缩力的工作机制。将人真皮成纤维细胞培养在 3D 培养水凝胶中，并通过注射器管装置施加 1.5 个大气压的外部压缩力，分别处理 4、8 和 20 小时。RNA-seq 鉴定出与对照细胞相比，在 8 小时的压缩干预后有 437 个差异调节基因，其中 256 个基因上调，181 个基因下调。进一步的 q-PCR 分析证实，早期生长反应 1（EGR1）和 c-fos 在 8 小时的压缩干预后下调。然而，通过 Western blot 在 8 和 20 小时的时间点，压力干预后 EGR1 和 c-fos 的下调并未导致蛋白质合成的改变。与成纤维细胞的纤维化功能密切相关的基因，包括 I 型胶原（COL1）、III 型胶原（COL3）、转化生长因子β1（TGF-β1）、基质金属蛋白酶 1（MMP1）、基质金属蛋白酶 1（TIMP1）、结缔组织生长因子（CTGF）、α 平滑肌肌动蛋白（α-SMA）和纤维连接蛋白 1（FN1），在压力处理 8 小时后也没有受到影响。本研究表明，在我们的 3D 水凝胶培养模型中，压力不会直接影响真皮成纤维细胞的纤维化功能。间接调节，包括减少水肿、血液灌注和张力，可能是压力治疗的一种更可能的机制。
