Scavenging Intracellular ROS Attenuates p-Cresyl Sulfate-Triggered Osteogenesis through MAPK Signaling Pathway and NF-κB Activation in Human Arterial Smooth Muscle Cells.

Jia-Feng Chang,Chi-Feng Hung,Jian-Chiun Liou,Chang-Chin Wu,Chih-Cheng Lin,Li-Li Wen,Cai-Mei Zheng,Mai-Szu Wu,Wen-Chin Ko,Chih-Yu Hsieh,Shih-Hao Liu,Shuk-Man Ka,Kuo-Cheng Lu

doi:10.3390/toxins12080472

Abstract

Osteogenesis in human arterial smooth muscle cell (HASMC) is a key feature of uremic vascular calcification (UVC). Concerning pro-oxidant properties of p-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 (Runx2) and alkaline phosphatase (ALP). In parallel with PCS accumulation, CKD arteries corresponded with UVC severity, oxidative DNA damage (8-hydroxy-2′-deoxyguanosine), Runx2 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 Runx2 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 Runx2 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.

Highlights

Cardiovascular (CV) disease remains the most prevalent cause of death in patients with chronic kidney disease (CKD) to date, and uremic vascular calcification (UVC) is at the heart of the matter [1,2,3].Chronic mineral dysregulation in CKD patients promotes UVC and culminates in premature CV death, even in the early stages of the disease [4,5,6]
The representative protein-bound uremic toxins (PBUT), p-cresyl sulfate (PCS) and indoxyl sulfate (IS), exert pro-oxidant and pro-inflammatory effects on diverse cell and organ systems [8,9] PCS mainly presents as a protein-bound form in the blood circulation, and this study is focusing on the free form of PCS [10]
Experimental data from cell and animal models suggest that reactive oxygen species (ROS) and chronic sustained inflammation resting from circulating PTUB are hallmarks of UVC and capable of pivotal inducers of osteogenesis in human arterial smooth muscle cell (HASMC) [11]

Summary

Introduction

Cardiovascular (CV) disease remains the most prevalent cause of death in patients with chronic kidney disease (CKD) to date, and uremic vascular calcification (UVC) is at the heart of the matter [1,2,3].Chronic mineral dysregulation in CKD patients promotes UVC and culminates in premature CV death, even in the early stages of the disease [4,5,6]. Cardiovascular (CV) disease remains the most prevalent cause of death in patients with chronic kidney disease (CKD) to date, and uremic vascular calcification (UVC) is at the heart of the matter [1,2,3]. Experimental data from cell and animal models suggest that reactive oxygen species (ROS) and chronic sustained inflammation resting from circulating PTUB are hallmarks of UVC and capable of pivotal inducers of osteogenesis in human arterial smooth muscle cell (HASMC) [11]. The pro-calcific effect of solely PCS on the actively cell-regulated process of osteogenic conversion in HASMC remains elusive, resting in a lack of in-depth understanding of the molecular mechanism and therapeutic targets, we aimed to investigate the therapeutic effect of intracellular ROS scavenger on PCS triggered inflammatory signaling transduction in HASMC osteogenesis

Objectives

Methods

Results

Discussion

Conclusion