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We formerly proved that uremic vascular calcification (UVC) correlates tightly with oxidative elastic lamina (EL) injury and two cell fates (apoptosis and osteocytic conversion) in smooth muscle cells (SMC) of chronic kidney disease (CKD) patients and eliminating p-cresyl sulfate (PCS)-activated intracellular ROS ameliorates the MAPK signaling pathway in a human arterial SMC (HASMC) model. Nonetheless, whether ROS scavenger attenuates PCS-triggered inflammasome activation and eicosanoid inflammation in the UVC process remains unknown. Patients with lower extremity amputation were categorized into CKD and normal control group according to renal function. We used immunohistochemistry stain to analyze UVC in arterial specimens, including oxidative injury (8-hydroxy-2′-deoxyguanosine (8-OHdG) and internal EL disruption), cytosolic phospholipase A2 (cPLA2), cyclooxygenase 2 (COX2), interleukin-1 beta (IL-1β), caspase-1 and NLRP3. To simulate the patho-mechanism of human UVC, the therapeutic effects of ROS scavenger on PCS-triggered inflammatory pathways was explored in a HASMC model. We found CKD patients had higher circulating levels of PCS and an increase in medial arterial calcification than the control group. In CKD arteries, the severity of UVC corresponded with expressions of oxidative EL disruption and 8-OHdG. Furthermore, coupling expressions of cPLA2 and COX2 were accentuated in CKD arteries, indicative of eicosanoid inflammation. Notably, tissue expressions of IL-1β, caspase-1 and NLRP3 were enhanced in parallel with UVC severity, indicative of inflammasome activation. From bedside to bench, ROS scavenger attenuates PCS-activated expressions of cPLA2/COX2, pro-caspase-1 and NLRP3 in the HASMC model. UVC as an inevitable outcome is predictive of death in CKD patients. Nonetheless, UVC remain pharmacoresistant despite the evolution of treatment for mineral-parathyroid hormone-vitamin D axis. Beyond the mineral dysregulation, the stimulation of pro-oxidant PCS alone results in eicosanoid inflammation and inflammasome activation. Concerning the key role of Caspase-1 in pyroptosis, cell fates of HASMC in uremic milieu are not limited to apoptosis and osteogenesis. In view of this, reducing ROS and PCS may act as a therapeutic strategy for UVC-related cardiovascular events in CKD patients.

SUMMARY: Clinically relevant renal lesions in rheumatoid arthritis (RA) are not common. More often renal involvement is related to complications of therapy than the disease itself. The most common forms of primary renal disease in RA are membranous glomerulonephropathy and a pure mesangial proliferative glomerulonephritis. Some studies have described the association between crescentic glomerulonephritis (crescentic GN) and RA, but they were all found to be perinuclear antineutrophil cytoplasmic antibody (p-ANCA) positive. However, RA associated with ANCA negative pauci-immue crescentic GN has not been reported. This is a case report of a 37-year-old female with RA who initially presented with general oedema and acute deterioration of renal function. The renal biopsy revealed ANCA negative pauci-immune crescentic GN. The patient was treated with steroid pulse and plasmapheresis, but not cyclophosphamide because of severe urosepsis. Despite the use of aggressive therapy, her renal function was not improved and she underwent maintenance haemodialysis thereafter. Because ANCA negative crescentic GN may occur in RA patients without frank systemic vasculitis, but with severe clinical manifestation, a heightened suspicion for a relatively ‘silent’ crescentic GN would have led to the correct diagnosis and appropriate treatment. [ABSTRACT FROM AUTHOR]