Felizari Luana D, Bowman Sydney M, Crasto Chiquito J, Sarturi Jhones O, Woerner Dale R, Johnson Bradley J
Department of Animal and Food Sciences, Texas Tech University, Lubbock, Texas, United States of America.
Center for Biotechnology and Genomics, Texas Tech University, Lubbock, Texas, United States of America.
PLoS One. 2025 Jun 9;20(6):e0324209. doi: 10.1371/journal.pone.0324209. eCollection 2025.
Liver abscesses are a significant concern in cattle feeding, linked to visceral condemnation and carcass trimming; however, the molecular mechanism of development and progression of liver abscesses is unknown. This study aimed to evaluate the hepatic transcriptomic profile, immunohistochemistry, and IGF-I circulation in beef × dairy (Angus × Holstein) steers with and without liver abscesses. Samples were collected from twelve steers (final body weight of 719 ± 5.8 kg) originating from the same feedlot and were selected based on liver scores at harvest. The animals were divided into abscessed (n = 6) and healthy livers (n = 6). Blood samples were used to measure circulating insulin-like growth factor I (IGF-I) levels using an ELISA kit. Liver samples were divided into two portions; one portion was used for immunohistochemistry (IHC) to identify IGF-I receptor (IGF-IR) abundance, while the second portion was used for RNA extraction, library preparation, and sequencing (Illumina NovaSeq 6000 platform). Differentially expressed genes (DEGs) were identified with the DESeq2 R package, using an adjusted p-value ≤ 0.05 and fold change > 1.5. Sera IGF-I was not affected by liver condition; however, IGF-IR abundance was up-regulated in abscessed livers. A total of 568 DEGs were identified, with 372 up-regulated and 196 down-regulated in abscessed livers. Notably, the most highly up-regulated genes were FGF23, NXPH4, and CYP7A1, while EPHA6, CD70, and INHBA showed the most significant downregulation. Protein-protein interaction (PPI) network analysis identified THBS1 and COL1A2 as significant hub genes. The DEGs showed enrichment in biological processes related to angiogenesis, cell migration, adhesion, and extracellular matrix organization. Pathway analysis indicated activation in signaling pathways, including hepatic fibrosis, interleukin, and IGF-I signaling. These findings reveal candidate genes and pathways linked to inflammatory responses and tissue remodeling, offering valuable evidence that enhances our understanding of the progression of liver abscesses in cattle.
肝脓肿是肉牛饲养中的一个重大问题，与内脏废弃和胴体修整有关；然而，肝脓肿发生和发展的分子机制尚不清楚。本研究旨在评估有和没有肝脓肿的肉用×乳用（安格斯×荷斯坦）公牛的肝脏转录组图谱、免疫组织化学和胰岛素样生长因子-I（IGF-I）循环情况。样本取自同一饲养场的12头公牛（最终体重719±5.8千克），并根据屠宰时的肝脏评分进行选择。将动物分为有脓肿组（n = 6）和健康肝脏组（n = 6）。使用酶联免疫吸附测定试剂盒，通过血样测量循环胰岛素样生长因子I（IGF-I）水平。肝脏样本分为两部分；一部分用于免疫组织化学（IHC）以鉴定IGF-I受体（IGF-IR）丰度，而第二部分用于RNA提取、文库制备和测序（Illumina NovaSeq 6000平台）。使用DESeq2 R软件包，以调整后的p值≤0.05和倍数变化>1.5来鉴定差异表达基因（DEG）。血清IGF-I不受肝脏状况影响；然而，IGF-IR丰度在有脓肿的肝脏中上调。共鉴定出568个DEG，其中372个在有脓肿的肝脏中上调，196个下调。值得注意的是，上调程度最高的基因是FGF23、NXPH4和CYP7A1，而EPHA6、CD70和INHBA下调最为显著。蛋白质-蛋白质相互作用（PPI）网络分析确定THBS1和COL1A2为重要的枢纽基因。这些DEG在与血管生成、细胞迁移、黏附和细胞外基质组织相关的生物学过程中富集。通路分析表明，包括肝纤维化、白细胞介素和IGF-I信号通路在内的信号通路被激活。这些发现揭示了与炎症反应和组织重塑相关的候选基因和通路，为增进我们对牛肝脓肿进展的理解提供了有价值的证据。
