Basu Proma, Kim Jane Hannah, Saeed Shayan, Martins-Green Manuela
Department of Molecular, Cell and Systems Biology, UC, Riverside, California, USA.
Wound Repair Regen. 2021 Nov;29(6):881-898. doi: 10.1111/wrr.12963. Epub 2021 Sep 18.
Chronic wounds are a significant health problem worldwide. However, nothing is known about how chronic wounds initiate and develop. Here we use a chronic wound model in diabetic mice and a Systems Biology Approach using nanoString nCounter technology and weighted gene correlation network analysis (WGCNA), with tissues collected at 6, 12, 24 and 48 h post-wounding, to identify metabolic signalling pathways involved in initiation of chronicity. Normalized counts obtained from the nanoString nCounter Mouse Metabolic Panel were used for the WGCNA, which groups genes into co-expression modules to visualize the correlation network. Genes with significant module membership and gene trait significance (p < 0.05) were used to identify signalling pathways that are important for the development of chronicity. The pathway analysis using the Reactome database showed stabilization of PTEN, which down-regulates PI3K/AKT1, which in turn down-regulates Nrf2, as shown by ELISA, thus disabling antioxidant production, resulting in high oxidative stress levels. We find that pathways involved in inflammation, including those that generate pro-inflammatory lipids derived from arachidonic acid metabolism, IFNγ and catecholamines, occur. Moreover, HIF3α is over-expressed, potentially blocking Hif1α and preventing activation of growth factors and cytokines that promote granulation tissue formation. We also find that FGF1 is under-expressed, while thrombospondin-1 is over-expressed, resulting in decreased angiogenesis, a process that is critical for healing. Finally, enzymes involved in glycolysis are down-regulated, resulting in decreased production of pyruvate, a molecule critical for ATP production, leading to extensive cell death and wound paralysis. These findings offer new avenues of study that may lead to the development of novel treatments of CW to be administered right after debridement.
慢性伤口是全球范围内一个重大的健康问题。然而，关于慢性伤口如何起始和发展却一无所知。在此，我们利用糖尿病小鼠的慢性伤口模型，并采用系统生物学方法，运用纳米串nCounter技术和加权基因共表达网络分析（WGCNA），在伤口形成后6、12、24和48小时收集组织，以识别参与慢性化起始的代谢信号通路。从纳米串nCounter小鼠代谢面板获得的标准化计数用于WGCNA，该分析将基因分组到共表达模块中以可视化相关网络。具有显著模块成员关系和基因特征显著性（p < 0.05）的基因用于识别对慢性化发展重要的信号通路。使用Reactome数据库进行的通路分析显示PTEN稳定，这会下调PI3K/AKT1，进而下调Nrf2（如ELISA所示），从而抑制抗氧化剂的产生，导致高氧化应激水平。我们发现涉及炎症的通路，包括那些产生源自花生四烯酸代谢的促炎脂质、IFNγ和儿茶酚胺的通路出现。此外，HIF3α过度表达，可能会阻断Hif1α并阻止促进肉芽组织形成的生长因子和细胞因子的激活。我们还发现FGF1表达不足，而血小板反应蛋白-1表达过度，导致血管生成减少，而血管生成是愈合过程中的关键环节。最后，参与糖酵解的酶下调，导致丙酮酸生成减少，丙酮酸是ATP生成的关键分子，从而导致广泛的细胞死亡和伤口愈合停滞。这些发现提供了新的研究途径，可能会促成清创后立即施用的新型慢性伤口治疗方法的开发。
