Abstract P217: Mitochondrial N-Formyl Peptides Elicit Changes in Endothelial Cell Cytoskeleton via Formyl Peptide Receptor Activation

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Camilla F Wenceslau ◽  
Cameron G McCarthy ◽  
R.Clinton Webb
Keyword(s):  
Endothelial Cells ◽  
Endothelial Cell ◽  
Vascular Dysfunction ◽  
Receptor Activation ◽  
Vascular Leakage ◽  
Formyl Peptide Receptor ◽  
Experimental Hypertension ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Formyl Peptides

One major pathophysiological characteristic of cardiovascular disease, including hypertension, is vascular dysfunction. Recently, we demonstrated that mitochondrial damage-associated molecular patterns are elevated in the circulation of SHR. Mitochondria carry hallmarks of their bacterial ancestry and one of these hallmarks is that this organelle still uses an N-formyl-methionyl-tRNA as an initiator of protein synthesis. We observed that mitochondrial N-formyl peptides (F-MIT) infusion into rats induces inflammation and vascular dysfunction, including vascular leakage, via formyl peptide receptor (FPR) activation. However, neutrophil depletion did not change this response. Therefore, we hypothesize that F-MIT via FPR activation elicits changes directly to cytoskeleton-regulating proteins in vascular cells, which may lead to increased vascular permeability. To test this hypothesis we used vascular smooth muscle cells (VSMC) and endothelial cells harvested from aortas of Sprague-Dawley rats (n=5) and human donors (n=5), respectively. Cells were divided into three groups for Western blot analysis of cytoskeleton-regulating proteins. The cells were incubated for 20 minutes in medium with either vehicle (non-formylated peptide), F-MIT (10 μM), or F-MIT after a 5-minute pre-incubation with FPR1 and 2 antagonists (Cyclosporine H, CsH, 1 μM and WRW4, 10 μM). In endothelial cells, the treatment with F-MIT increased the protein expression of RhoA/ROCK (Rho: 1.8 fold vs. Veh; ROCK: 1.4 fold vs. Veh, p<0.05), cell division control protein 42 (CDC42) (2.0 fold vs. Veh, p<0.05) and phospho-myosin light chain (MLC) Thr/Ser19 (1.5 fold vs. Veh, p<0.05). These changes were all abolished in the presence of FPR antagonists. On the other hand, F-MIT decreased expression of phospho-MLC (0.6 fold vs. Veh, p<0.05) and CDC42 (0.5 fold vs. Veh, p<0.05) and did not change RhoA/ROCK expression in VSMC. In conclusion, F-MIT, via FPR activation, elicits direct changes in endothelial cell and VSMC cytoskeleton-regulating proteins. This interaction can lead to endothelial contraction, increased vascular leakage and attenuated barrier function as observed in clinical and experimental hypertension.

Mitochondrial N-formyl peptides cause airway contraction and lung neutrophil infiltration via formyl peptide receptor activation

2016 ◽  
Vol 37 ◽  
pp. 49-56 ◽  
Author(s):  
Camilla Ferreira Wenceslau ◽  
Theodora Szasz ◽  
Cameron G. McCarthy ◽  
Babak Baban ◽  
Elizabeth NeSmith ◽  
...  
Keyword(s):  
Neutrophil Infiltration ◽  
Receptor Activation ◽  
Formyl Peptide Receptor ◽  
Peptide Receptor ◽  
Formyl Peptide ◽  
Formyl Peptides

Formyl peptide receptor 1 signaling potentiates inflammatory brain injury

2021 ◽  
Vol 13 (605) ◽  
pp. eabe9890
Author(s):  
Zhiguo Li ◽  
Yulin Li ◽  
Jinrui Han ◽  
Zilong Zhu ◽  
Minshu Li ◽  
...  
Keyword(s):  
Brain Edema ◽  
Brain Inflammation ◽  
Formyl Peptide Receptor ◽  
Neurological Deficits ◽  
Peptide Receptor ◽  
Neurological Outcomes ◽  
Molecular Pattern ◽  
Formyl Peptide ◽  
Molecular Landscape ◽  
Formyl Peptides

Acute brain insults elicit pronounced inflammation that amplifies brain damage in intracerebral hemorrhage (ICH). We profiled perihematomal tissue from patients with ICH, generating a molecular landscape of the injured brain, and identified formyl peptide receptor 1 (FPR1) as the most abundantly increased damage-associated molecular pattern (DAMP) receptor, predominantly expressed by microglia. Circulating mitochondrial N-formyl peptides, endogenous ligands of FPR1, were augmented and correlated with the magnitude of brain edema in patients with ICH. Interactions of formyl peptides with FPR1 activated microglia, boosted neutrophil recruitment, and aggravated neurological deficits in two mouse models of ICH. We created an FPR1 antagonist T-0080 that can penetrate the brain and bind both human and murine FPR1. T-0080 attenuated brain edema and improved neurological outcomes in ICH models. Thus, FPR1 orchestrates brain inflammation after ICH and could be targeted to improve clinical outcome in patients.

Abstract 22: Formyl Peptide Receptor-1 Activation Is Crucial For The Cause Of Spontaneous Hypertension In Dahl Salt Sensitive Rats

Hypertension ◽  
2020 ◽  
Vol 76 (Suppl_1) ◽  
Author(s):  
Jonnelle M Edwards ◽  
Sarah Galla ◽  
Nicole R Bearss ◽  
Blair Mell ◽  
Xi Cheng ◽  
...  
Keyword(s):  
Vascular Injury ◽  
Vascular Function ◽  
Vascular Dysfunction ◽  
Formyl Peptide Receptor ◽  
Spontaneous Hypertension ◽  
Leaky Gut ◽  
Cell Necrosis ◽  
Resistance Arteries ◽  
Peptide Receptor ◽  
Formyl Peptide

Mitochondria evolved from bacteria and use N-formylated peptides (NFPs) to synthetize protein. Bacterial and mitochondrial NFPs activate formyl peptide receptor 1 (FPR-1) and lead to vascular injury. We previously observed that Dahl Salt Sensitive rats (S) fed a low-salt (LS, 0.3% NaCl) diet presented spontaneous hypertension, vascular dysfunction, and overexpression of FPR-1 in arteries when compared to Dahl Salt Resistant (R) rats. High salt (HS, 2% NaCl) diet worsened these phenotypes in S rats. Interestingly, HS diet induced leaky gut and amoxicillin (AMO) treatment decreased BP in S-HS. Due to the dual sources of NFPs (microbiota and host mitochondria), we hypothesized that cell death-derived mitochondria and/or leaky gut-derived bacterial NFPs lead to FPR-1 activation, vascular injury and elevated BP in S rats independent of HS diet. For this, we used flow cytometry to measure cell necrosis and early and late apoptosis in kidney, bone marrow-derived macrophages and mesenteric resistance arteries (MRA) from male S and R rats (8-week old) on a LS diet. Zonulin, a biomarker for leaky gut, was measured in plasma. In another group, rats were treated with FPR-1 antagonist [Cyclosporin H (CsH), 0.3 mg/kg/day, osmotic mini-pump, 14 days], vehicle (VEH) or received water with AMO (5 mg/kg/day) for 21 days to deplete bacteria. BP was measured by telemetry and vascular function and structure were assessed in MRA. S rats presented increased kidney cell necrosis (R: 3.8±0.3 vs. S: 5.3±0.5* %). CsH decreased spontaneous elevation of BP [Diastolic: R+VEH: 77±2.7 vs. R+CsH: 81±1.2 vs. S+VEH: 126±3.0* vs. S+CsH:115±2.7 # ] and vascular hypercontractility [KCl (120mM): R+VEH: 9.4±1 vs. R+CsH: 10.2±0.4; S+VEH: 15.5±0.9* vs. S+CsH:11.7±0.8 # mN; Phenylephrine (10μM): R+VEH: 9.3±1 vs. R+CsH: 9.7±1; S+VEH: 14.5±1*vs. S+CsH: 11.4±0.6 # mN) in S-LS rats. AMO did not change vascular contraction or BP. Leaky gut was not observed in Dahl S-LS diet. In conclusion, FPR-1 can serve as a causative agent for the spontaneous elevation of BP and kidney-derived mitochondria, but not gut-derived microbiota, are the main source for NFPs.

Abstract 069: Intrarenal Arteries Sense Mitochondrial N-formyl Peptides via Formyl Peptide Receptor in Wistar and Spontaneously Hypertensive Rats (shr)

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Camilla F Wenceslau ◽  
Cameron G McCarthy ◽  
Safia Ogbi ◽  
Paul M O'Connor ◽  
R. Clinton Webb
Keyword(s):  
Protein Expression ◽  
Ex Vivo ◽  
Kidney Injury ◽  
Formyl Peptide Receptor ◽  
Peptide Receptor ◽  
Immune System Activation ◽  
Formyl Peptide ◽  
Wistar Kyoto ◽  
Formyl Peptides

It is well established that chronic immune system activation contributes to hypertension and kidney injury. Mitochondria carry hallmarks of their bacterial ancestry and thus have emerged as a significant source of inflammatogenic damage-associated molecular patterns (DAMPs). One of these hallmarks is that it still uses an N-formyl-methionyl-tRNA as an initiator of protein synthesis. Recently, we have observed that mitochondrial DAMPs are elevated in the circulation of SHR, and that mitochondrial N-formyl peptides (F-MIT) infusion in rats induces systemic inflammation and vascular dysfunction via formyl peptide receptor (FPR) activation. However, we do not know if FPR plays a role in kidney injury and hypertension. We hypothesized that F-MIT activate FPR and lead to intrarenal dysfunction in 12 week old male Wistar and SHR (n=4-8). Wistar rats were treated with F-MIT (0.02 mg/kg) or non-formylated peptide (control) for 6 h and intrarenal arteries (diameter >100 μm) were isolated. To exclude systemic effects of F-MIT, intrarenal arteries were also isolated from control rats and treated ex vivo with 100 nM F-MIT or non-formylated peptide. F-MIT treatment in vivo increased intrarenal arteries FPR protein expression (2.3-fold vs. control) and decreased β-arrestin 2 (protein that internalizes FPR upon activation) and phosphorylation of endothelial nitric oxide synthase (4-fold vs. control). These results were reproduced in isolated arteries incubated with F-MIT or control for 6 h ex vivo. Similarly, in intrarenal arteries from untreated SHR, we found that FPR protein expression was higher (1.5-fold vs. Wistar Kyoto, WKY) and β-arrestin 2 protein expression was decreased (2-fold vs. WKY). Interestingly, although treatment with hydrochlorothiazide (10-55 mg/kg/day) and reserpine (0.6-4.5 mg/kg/day) for 7 weeks attenuated the increase in blood pressure in SHR, anti-hypertensive therapy did not change FPR and β-arrestin 2 protein expression. Additionally, it was observed that the co-localization of FPR and β-arrestin 2 was decreased in intrarenal arteries from SHR. Overall, these data suggest that intrarenal arteries sense F-MIT. Also, FPR activation parameters following F-MIT treatment of normotensive rats are similar to those observed in SHR.

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