Division of Nephrology, Department of Internal Medicine, En Chu Kong Hospital, New Taipei City 237, Taiwan.
Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan.
Toxins (Basel). 2020 Jul 24;12(8):472. doi: 10.3390/toxins12080472.
Osteogenesis in human arterial smooth muscle cell (HASMC) is a key feature of uremic vascular calcification (UVC). Concerning pro-oxidant properties of -cresyl sulfate (PCS), the therapeutic effect of reactive oxygen species (ROS) scavenger on PCS triggered inflammatory signaling transduction in osteogenesis was investigated in this translational research. Based on severity level of chronic kidney disease (CKD), arterial specimens with immunohistochemistry stain were quantitatively analyzed for UVC, oxidative injury and osteogenesis along with PCS concentrations. To mimic human UVC, HASMC model was used to explore whether PCS-induced ROS could trigger mitogen-activated protein kinase (MAPK) pathways with nuclear factor-κB (NF-κB) translocation that drive context-specific gene/protein expression, including Runt-related transcription factor 2 () and alkaline phosphatase (ALP). In parallel with PCS accumulation, CKD arteries corresponded with UVC severity, oxidative DNA damage (8-hydroxy-2'-deoxyguanosine), and ALP. PCS directly phosphorylated extracellular signal-regulated kinase (ERK)/c-Jun N-terminal kinase (JNK)/P38 (pERK/pJNK/pP38) and modulated NF-κB translocation to promote expressions of and ALP in HASMC. Notably, intracellular ROS scavenger attenuated pERK signaling cascade and downstream osteogenic differentiation. Collectively, our data demonstrate PCS induces osteogenesis through triggering intracellular ROS, pERK/pJNK/pP38 MAPK pathways and NF-κB translocation to drive and ALP expressions, culminating in UVC. Beyond mineral dysregulation, osteocytic conversion in HASMC could be the stimulation of PCS. Thus PCS may act as a pro-osteogenic and pro-calcific toxin. From the perspective of translational medicine, PCS and intracellular ROS could serve as potential therapeutic targets for UVC in CKD patients.
人动脉平滑肌细胞（HASMC）中的成骨作用是尿毒症血管钙化（UVC）的一个关键特征。鉴于 - 甲苯硫酸（PCS）的促氧化剂特性，本研究在转化研究中调查了活性氧（ROS）清除剂对PCS 触发成骨炎症信号转导的治疗作用。根据慢性肾脏病（CKD）的严重程度，通过免疫组织化学染色对动脉标本进行定量分析，以评估 UVC、氧化损伤和成骨作用以及 PCS 浓度。为了模拟人类 UVC，使用 HASMC 模型来探讨 PCS 诱导的 ROS 是否可以触发丝裂原活化蛋白激酶（MAPK）途径，从而驱动核因子-κB（NF-κB）易位，驱动特定背景的基因/蛋白表达，包括 Runt 相关转录因子 2（）和碱性磷酸酶（ALP）。随着 PCS 的积累，CKD 动脉与 UVC 的严重程度、氧化 DNA 损伤（8-羟基-2'-脱氧鸟苷）和 ALP 相对应。PCS 直接磷酸化细胞外信号调节激酶（ERK）/c-Jun N-末端激酶（JNK）/P38（pERK/pJNK/pP38）并调节 NF-κB 易位，以促进 HASMC 中 的表达和 ALP。值得注意的是，细胞内 ROS 清除剂减弱了 pERK 信号级联反应和下游成骨分化。总之，我们的数据表明 PCS 通过触发细胞内 ROS、pERK/pJNK/pP38 MAPK 途径和 NF-κB 易位来诱导成骨作用，从而驱动 和 ALP 的表达，最终导致 UVC。除了矿物质失调之外，HASMC 中的成骨细胞转化也可能是 PCS 的刺激。因此，PCS 可能是一种促成骨和促钙化毒素。从转化医学的角度来看，PCS 和细胞内 ROS 可以作为 CKD 患者 UVC 的潜在治疗靶点。
