Abstract 13855: The Impact of Plasma Levels of Receptor for Advanced Glycation End-products and High Mobility Group Box 1 in Patients With Pulmonary Hypertension

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Satoshi Suzuki ◽  
Kazuhiko Nakazato ◽  
Koichi Sugimoto ◽  
Akiomi Yoshihisa ◽  
Takayoshi Yamaki ◽  
...  

Background: In pulmonary hypertension (PH), the increase of pulmonary artery pressure by vasoconstriction, remodeling of small pulmonary arteries, and chronic pulmonary thromboembolism result in right ventricular failure and ultimately death. Nuclear protein, high mobility group box 1 (HMGB1), stabilizes nucleosome, and on release into extracellular environment, HMGB1 acts as a pro-inflammatory cytokine by activating pattern recognition receptors including receptor for advanced glycation end-products (RAGE). HMGB1 is one of endogenous ligands of RAGE, and HMGB1 and RAGE are ubiquitously expressed in various organs. Several reports have recently revealed that RAGE is expressed in pulmonary artery in patients with PH, and HMGB1 contributes to migration of vascular smooth muscle cells in PH patient. The purpose of this study was to examine the clinical significance of circulating levels of HMGB1 and RAGE in patients with PH. Methods and Results: Plasma levels of HMGB1 and soluble RAGE were measured in 33 patients with PH (9 in idiopathic PH, 7 in PH related to collagen disease, 9 in chronic thromboembolic PH (CTEPH), 8 in others) and 30 normal subjects as control. Plasma levels of HMGB1 were not difference between PH patients and control subjects, however, plasma levels of soluble RAGE were significantly higher in patients with PH than in control (1464.2 vs. 831.7 pg/ml, P=0.008). Plasma soluble RAGE levels were higher in idiopathic PH (P<0.001), PH related to collagen disease (P=0.050), and CTEPH (P=0.002) than control. In addition, there was statistically significant positive correlation between pressure gradient of tricuspid valve and plasma level of soluble RAGE (R=0.403, P=0.019). Conclusions: Plasma levels of soluble RAGE, but not HMGB1, might be a novel marker which reflects the pathological conditions in patients with PH.

2016 ◽  
Vol 57 (2) ◽  
pp. 234-240 ◽  
Author(s):  
Satoshi Suzuki ◽  
Kazuhiko Nakazato ◽  
Koichi Sugimoto ◽  
Akiomi Yoshihisa ◽  
Takayoshi Yamaki ◽  
...  

2015 ◽  
Vol 309 (8) ◽  
pp. F720-F730 ◽  
Author(s):  
David W. Good ◽  
Thampi George ◽  
Bruns A. Watts

High-mobility group box 1 (HMGB1) is a damage-associated molecule implicated in mediating kidney dysfunction in sepsis and sterile inflammatory disorders. HMGB1 is a nuclear protein released extracellularly in response to infection or injury, where it interacts with Toll-like receptor 4 (TLR4) and other receptors to mediate inflammation. Previously, we demonstrated that LPS inhibits HCO3- absorption in the medullary thick ascending limb (MTAL) through a basolateral TLR4-ERK pathway (Watts BA III, George T, Sherwood ER, Good DW. Am J Physiol Cell Physiol 301: C1296–C1306, 2011). Here, we examined whether HMGB1 could inhibit HCO3- absorption through the same pathway. Adding HMGB1 to the bath decreased HCO3− absorption by 24% in isolated, perfused rat and mouse MTALs. In contrast to LPS, inhibition by HMGB1 was preserved in MTALs from TLR4−/− mice and was unaffected by ERK inhibitors. Inhibition by HMGB1 was eliminated by the receptor for advanced glycation end products (RAGE) antagonist FPS-ZM1 and by neutralizing anti-RAGE antibody. Confocal immunofluorescence showed expression of RAGE in the basolateral membrane domain. Inhibition of HCO3−absorption by HMGB1 through RAGE was additive to inhibition by LPS through TLR4 and to inhibition by Gram-positive bacterial molecules through TLR2. Bath amiloride, which selectively prevents inhibition of MTAL HCO3− absorption mediated through Na+/H+ exchanger 1 (NHE1), eliminated inhibition by HMGB1. We conclude that HMGB1 inhibits MTAL HCO3− absorption through a RAGE-dependent pathway distinct from TLR4-mediated inhibition by LPS. These studies provide new evidence that HMGB1-RAGE signaling acts directly to impair the transport function of renal tubules. They reveal a novel paradigm for sepsis-induced renal tubule dysfunction, whereby exogenous pathogen-associated molecules and endogenous damage-associated molecules act directly and independently to inhibit MTAL HCO3− absorption through different receptor signaling pathways.


2019 ◽  
Vol 32 (2) ◽  
pp. 89-94 ◽  
Author(s):  
Nafise Yaghouti ◽  
Reza Boostani ◽  
Asadollah Mohamamdi ◽  
Zohreh Poursina ◽  
Seyed Abdolrahim Rezaee ◽  
...  

2002 ◽  
Vol 363 (3) ◽  
pp. 529-535 ◽  
Author(s):  
Bianca SPARATORE ◽  
Marco PEDRAZZI ◽  
Mario PASSALACQUA ◽  
Deborah GAGGERO ◽  
Mauro PATRONE ◽  
...  

In several cell types the binding of extracellular high-mobility group-box protein 1 (HMGB1) with the receptor for advanced glycation end-products (RAGE) induces cytoskeletal reorganization and cell motility. To establish whether RAGE is also involved in murine erythroleukaemia (MEL) cell differentiation stimulated by HMGB1, we have demonstrated that these cells express a 51kDa protein identified as RAGE, and then we have produced stable transfectants overexpressing wild-type (wt) RAGE or a dominant negative (dn) RAGE mutant lacking the cytoplasmic domain to analyse the differentiation process in these cells. Several experimental findings indicated that RAGE was not involved in the MEL cell differentiation programme. This was also supported by the identical stimulatory effect exerted by HMGB1 on both wt- or dn-RAGE transfectants. We have also observed that HMGB1 binds a 65kDa protein on the surface of MEL cells, supporting the hypothesis that alternative targets of HMGB1 are expressed on the MEL cell membrane and may be involved as mediators of its signalling.


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