Abstract 098: Foxp3+ T Regulatory Lymphocytes Counteract Angiotensin Ii-induced Vascular Injury

Hypertension ◽  
2014 ◽  
Vol 64 (suppl_1) ◽  
Author(s):  
Muhammad Oneeb Rehman Mian ◽  
Tlili Barhoumi ◽  
Marie Briet ◽  
Adriana Cristina Ene ◽  
Asia Rehman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Endothelial Dysfunction ◽  
Vascular Injury ◽  
Adoptive Transfer ◽  
Ros Production ◽  
Ang Ii ◽  
Fibronectin Expression ◽  
Induced Hypertension ◽  
Regulatory Lymphocytes

Objective: T effector lymphocytes contribute to vascular injury in angiotensin (Ang) II-induced hypertension, but the role of T regulatory lymphocytes (Tregs) is unclear. Ang II-induced hypertension is blunted in T and B lymphocyte-deficient (Rag1-/-) mice, and restored with reconstitution of T cells. We hypothesized that adoptive transfer of FOXP3-deficient Scurfy (Sf) vs. wild-type (WT) T cells will exacerbate Ang II-induced vascular damage in Rag1-/- mice. Methods: Eleven-week old male Rag1-/- mice were injected IV with vehicle, 10 million WT or Sf T cells, 1 million CD4+CD25+ Tregs alone or with Sf T cells, and 2 weeks later were infused or not with Ang II (490 ng/kg/min, SC) for 14 days (n=3-8). Telemetric BP, vascular function and structure, and reactive oxygen species (ROS) production and fibronectin expression in mesenteric arteries (MA) were determined. Results: Ang II induced a 40 mmHg systolic BP rise in all the groups, but diastolic BP rise was ~10 mmHg greater in WT and Sf T cell-injected mice than in controls (P<0.01). Treg injection alone or with Sf T cells prevented or delayed by 7 days the BP rise, respectively (P<0.05). Ang II did not induce endothelial dysfunction in vehicle or Treg only-injected mice. Adoptive transfer of WT T cells restored Ang II induced-endothelial dysfunction (60±5% vs. 83±4%, P<0.05), which was exaggerated in Sf T cell-injected mice (56±6% vs. 97±7%, P<0.01), but reduced by Treg co-injection (74±4%, P<0.05). Ang II increased ROS production in MA wall (239±32% vs. 119±20%) and perivascular fat (369±39% vs. 84±8%) in Sf T cell-injected mice (P<0.01), but not when co-injected with Tregs. Ang II induced increased vascular stiffness (P<0.01) and media/lumen (M/L, P<0.05) in vehicle (strain at 140 mmHg: 0.60±0.02 vs. 0.80±0.02; M/L: 4.1±0.2 vs. 2.9±0.2%) and Sf T cell-injected mice (strain at 140 mmHg: 0.63±0.01 vs. 0.89±0.04; M/L: 4.7±0.3 vs. 2.9±0.1%). Ang II increased MA fibronectin expression (P<0.01) in vehicle (113±12 vs. 51±14 RFU/μm2) and Sf T cell-injected mice (85±7 vs. 36±9 RFU/μm2). Conclusion: These results demonstrate that Foxp3+ Tregs have a protective role against Ang II-induced vascular dysfunction, remodeling and oxidative stress.

Abstract 46: FOXP3+ T Regulatory Lymphocytes Counteract Angiotensin II-Induced Vascular Injury

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Muhammad Oneeb Rehman Mian ◽  
Tlili Barhoumi ◽  
Marie Briet ◽  
Adriana Cristina Ene ◽  
Asia Rehman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Endothelial Dysfunction ◽  
T Lymphocytes ◽  
Vascular Injury ◽  
Mesenteric Arteries ◽  
Ros Production ◽  
Ang Ii ◽  
Induced Hypertension ◽  
Regulatory Lymphocytes

Introduction: T lymphocytes participate in the low-grade inflammatory response that causes vascular injury in angiotensin (Ang) II-induced hypertension. Ang II-induced hypertension and endothelial dysfunction are blunted in T and B lymphocyte-deficient ( Rag1 -/- ) mice, and restored with reconstitution of T cells. However, the role of T regulatory lymphocytes (Treg) in Ang II-induced vascular injury is unclear. We hypothesized that adoptive transfer of FOXP3-deficient (Scurfy) T lymphocytes vs. wild-type (WT) cells will exacerbate Ang II-induced vascular damage in Rag1 -/- mice. Methods: Eleven-week old male Rag1 -/- mice were injected IV with PBS/2% FBS (control), 10 7 WT or Scurfy T lymphocytes, and 2 weeks later underwent sham surgery or were infused with Ang II (490 ng/kg/min, s.c.) using mini-osmotic pumps for 14 days (n=3-8). Systolic (SBP) and diastolic (DBP) blood pressure were measured by telemetry. Vascular function and structure were assessed in second order mesenteric arteries by pressurized myography. Reactive oxygen species (ROS) production and fibronectin and collagen I and III expression were determined in aorta. Results: Ang II induced a 40 mmHg SBP rise in Rag1 -/- mice for all treatment groups, but DBP rise was ~10 mmHg greater for WT and Scurfy T cell-injected mice than for control mice ( P <0.01). Adoptive transfer of WT T cells restored Ang II induced-endothelial dysfunction in mesenteric arteries ( P <0.05), which was exaggerated in Scurfy T cell-injected mice ( P <0.01). Ang II induced a greater increase in ROS production in aortic perivascular fat of Scurfy T cell-injected mice compared to WT T cell-injected mice ( P <0.05). Ang II induced mesenteric artery stiffness ( P <0.01) and hypertrophic remodeling ( P <0.05) in control and Scurfy T cell-injected mice, but not in WT T cell-injected mice. Ang II increased fibronectin expression to a greater extent in the aorta of control and Scurfy T cell-injected mice compared to WT T cell-injected mice ( P <0.01). Collagen I and III content was greater in the aorta of control and Scurfy T cell-injected mice than in WT T cell-injected mice ( P <0.01), but expression was unaltered by Ang II treatment. Conclusion: Foxp3+ T regulatory lymphocytes have a protective role against Ang II-induced vascular remodeling.

Abstract P347: γδ T Cells Drive CD4 + And CD8 + T Cell Activation In Hypertension

Hypertension ◽  
2017 ◽  
Vol 70 (suppl_1) ◽  
Author(s):  
Antoine Caillon ◽  
Pierre Paradis ◽  
Ernesto L Schiffrin
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Lymphocytes ◽  
Vascular Injury ◽  
T Cell Activation ◽  
Cell Activation ◽  
Γδ T Cells ◽  
Ang Ii ◽  
Adaptive Immune Cells ◽  
Induced Hypertension

Objective: Both innate (monocyte/macrophages) and adaptive immune cells (T lymphocytes) have been shown to play a role in the development of vascular injury in hypertension. Recently, we demonstrated that a small subset of “innate-like” T lymphocytes, expressing the γ/δ T cell receptor (TCR) rather than the αβ TCR, plays a key role in hypertension and vascular injury. We demonstrated an increased number and activation (CD69 + ) of γδ T cells during the development of hypertension caused by angiotensin (Ang) II infusion, and that deficiency in γδ T cells prevented Ang II-induced hypertension, resistance artery endothelial dysfunction and spleen T-cell activation in mice. We hypothesized that γδ T cells mediate activation of other T cells in hypertension. Method and Results: Fourteen to 15-week old male C57BL/6 wild-type (WT) mice were infused with Ang II (490 ng/kg/min, SC) for 3, 7 and 14 days (n=5-7) and spleen T cell profile was determined by flow cytometry. A correlation was demonstrated between the frequency (FREQ) and the number (#) of activated CD69 + γδ T cells and CD4 + CD69 + T cells (FREQ: r=0.41, P <0.05 and #: r=0.58, P <0.001) and CD8 + CD69 + T cells (FREQ: r=0.36, P <0.05 and #: r=0.50, P <0.01). We also demonstrated a high correlation between the # of CD69 + γδ T cells expressing CD27, a marker of interferon-γ expressing cells and a member of the T-T interaction molecules, with CD4 + CD69 + (r=0.88, P <0.001) and CD8 + CD69 + (r=0.81, P <0.01) T cells after 7 days of Ang II infusion. Conclusion: This study demonstrated an association between CD27 + CD69 + γδ T cells and activated T cells. These results suggest that γδ T cells drive activation of other T cells in Ang II-induced hypertension. Targeting γδ T cells may contribute to reduce inflammation in hypertension.

Splenocyte transfer from hypertensive donors eliminates premenopausal female protection from Ang II-induced hypertension

2022 ◽  
Author(s):  
Megan A Sylvester ◽  
Dennis P Pollow ◽  
Caitlin Moffett ◽  
Wendy Nunez ◽  
Jennifer L Uhrlaub ◽  
...  
Keyword(s):  
Blood Pressure ◽  
T Cells ◽  
Adoptive Transfer ◽  
T Regulatory Cells ◽  
Estrogen Signaling ◽  
Ang Ii ◽  
Regulatory Cells ◽  
Adaptive Immune Cells ◽  
Induced Hypertension ◽  
Rag 1

Premenopausal females are protected from Angiotensin II (Ang II)-induced hypertension following the adoptive transfer of T cells from normotensive donors. For the present study, we hypothesized that the transfer of hypertensive T cells (HT) or splenocytes (HS) from hypertensive donors would eliminate premenopausal protection from hypertension. Premenopausal Rag-1-/- females received either normotensive (NT) or hypertensive cells, three weeks prior to Ang II infusion (14 days, 490 ng/kg/min). Contrary to our hypothesis, no increase in Ang II-induced blood pressure was observed in the NT/Ang or HT/Ang groups. Flow cytometry demonstrated that renal FoxP3+ T regulatory cells were significantly decreased and IHC showed an increase in renal F4/80+ macrophages in HT/Ang, suggesting a shift in the renal inflammatory environment despite no change in blood pressure. Renal mRNA expression of MCP-1, Endothelin-1, GPER-1 were significantly decreased in HT/Ang. The adoptive transfer of hypertensive splenocytes prior to Ang II infusion (HS/Ang) eliminated premenopausal protection from hypertension and significantly decreased splenic FoxP3+ T regulatory cells compared to females receiving normotensive splenocytes (NS/Ang). Expression of MIP-1a/CCL3, a potent macrophage chemokine was elevated in HS/Ang, however no increase in renal macrophage infiltration occurred. Together, these data show that in premenopausal females T cells from hypertensive donors are not sufficient to induce a robust Ang II mediated hypertension, in contrast, transfer of hypertensive splenocytes (consisting of T/B lymphocytes, dendritic cells, macrophages) is sufficient. Further work is needed to understand how innate and adaptive immune cells and estrogen signaling coordinate to cause differential hypertensive outcomes in premenopausal females.

Abstract 13: P2X7 Receptor Knockout Attenuates Angiotensin II-Induced Hypertension, Vascular Injury And CD8 + T Cell Infiltration

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Brandon G Shokoples ◽  
Kevin Comeau ◽  
Akinori Higaki ◽  
Antoine Caillon ◽  
Pierre Paradis ◽  
...  
Keyword(s):  
T Cells ◽  
Vascular Injury ◽  
Mesenteric Artery ◽  
P2x7 Receptor ◽  
Ang Ii ◽  
Perivascular Adipose Tissue ◽  
T Cell Infiltration ◽  
Induced Hypertension ◽  
Post Menopausal ◽  
Aortic Stiffening

Background: The P2X7 receptor (P2RX7) recognizes damage associated molecule patterns such as adenosine triphosphate (ATP), and triggers the activation of immune cells. Elevated plasma ATP levels have been observed in hypertensive patients, providing a potential mechanism for P2RX7 activation. Additionally, a hypomorphic polymorphism for P2X7 is correlated with a decreased risk for essential hypertension in Chinese post-menopausal women. However, it is unknown whether P2RX7 activation contributes to angiotensin (Ang) II-induced blood pressure (BP) elevation and vascular damage. We hypothesized that P2rx7 knockout would blunt Ang II-induced BP elevation, vascular injury, and infiltration of activated immune T cells into perivascular adipose tissue (PVAT). Methods: Ten-to-12-week-old male C57BL/6J male wild-type (WT) and P2rx7 -/- mice were infused or not with Ang II (1000ng/kg/min) for 14 days. BP was determined by telemetry, mesenteric artery function and remodeling using pressurized myography, aortic stiffening by ultrasound and infiltration of activated immune T cells in aortic PVAT by flow cytometry. Results: Ang II-infused P2rx7 -/- mice display a reduced systolic BP (164±3 vs. 176±2 mm Hg, P <0.05) and pulse pressure (37±4 vs. 53±3 mm Hg, P <0.001) in comparison to WT mice. Aortic stiffening occurred in WT mice treated with Ang II, demonstrated by an increased pulse wave velocity (7.7±0.7 vs. 5.9±0.3 m/s, P <0.05), accompanied by a 3.8-fold increased infiltration of activated CD8 + T cells in aortic PVAT (60±16 vs 16±3 cells/aortic PVAT, P <0.001), which were both absent in P2rx7 -/- mice (6.4±1.4 vs 5.5±1.1 m/s and 27±7 vs 16±3 cells/aortic PVAT). In addition, the frequency of IFN-γ producing CD8 + T cells in the spleen of Ang II-treated WT mice increased (2.6±0.2% vs 1.2±0.2%), which did not occur in P2rx7 -/- mice (1.7±0.3% vs 1.7±0.2%). Ang II-infusion induced mesenteric artery endothelial dysfunction in WT mice (61±7 vs 83±4% relaxation response to acetylcholine, P <0.05), which was absent in P2rx7 -/- mice (89±3 vs 90±3%). Conclusion: P2rx7 knockout attenuates Ang II-induced hypertension, vascular injury, and infiltration of activated CD8 + T cells into aortic PVAT.

Abstract 252: 6ß-Hydroxytestosterone, A Cytochrome P450 1B1 Metabolite of Testosterone, Enhances Angiotensin II-Induced Pressor Effect in Male Mice

Hypertension ◽  
2013 ◽  
Vol 62 (suppl_1) ◽  
Author(s):  
Ajeeth K Pingili ◽  
Brett L Jennings ◽  
Nayaab S Khan ◽  
Kafait U Malik
Keyword(s):  
Cytochrome P450 ◽  
Endothelial Dysfunction ◽  
Ros Production ◽  
Oxygen Species ◽  
Pressor Effect ◽  
Ang Ii ◽  
Male Mice ◽  
Cytochrome P450 1B1 ◽  
Induced Hypertension ◽  
Novel Target

Androgens have been implicated in the development of hypertension and castration minimizes the pressor effect of angiotensin (Ang) II. Previously we showed that Ang II-induced hypertension and associated pathophysiological changes are diminished in male cytochrome P450 (CYP) 1B1 gene disrupted mice. Since CYP1B1 metabolizes testosterone to 6β-hydroxytestosterone (6β-OHT); this study was conducted to determine its contribution in modulation of Ang II-induced hypertension. Eight weeks old male Cyp1b1+/+ and Cyp1b1-/- mice were either castrated or injected with 6β-OHT (15 μg/g, i.p. every 3rd day) or vehicle (DMSO, 50 μl), infused with Ang II (700 ng/kg/min) or vehicle for 2 weeks, and systolic blood pressure (SBP) was measured by tail cuff. Castration attenuated Ang II-induced increase in SBP in both Cyp1b1+/+ (184 ± 6 vs. 129 ± 4 mmHg, P < 0.05) and Cyp1b1-/- mice (150 ± 6 vs. 129 ± 4 mmHg, P < 0.05). In Cyp1b1+/+ mice, 6β-OHT did not alter Ang II-induced increase in SBP (184 ± 6 vs. 180 ± 8 mmHg, P < 0.05), but enhanced it in Cyp1b1-/- mice (150 ± 6 vs. 172 ± 8 mmHg, P < 0.05). Castration improved endothelial dysfunction associated with Ang II-induced hypertension in Cyp1b1+/+ mice, as demonstrated by increased relaxation of the aorta to acetylcholine. No endothelial dysfunction was observed in Cyp1b1-/- mice given Ang II with or without castration. In Cyp1b1+/+ mice, 6β-OHT did not alter Ang II-induced endothelial dysfunction, however, in Cyp1b1-/- mice infused with Ang II, 6β-OHT caused endothelial dysfunction. We have shown that Ang II-induced hypertension is associated with increased vascular production of reactive oxygen species (ROS) in Cyp1b1+/+ mice, and this increase is attenuated in Cyp1b1-/- mice, as measured by dihydroethidium fluorescence. In both Cyp1b1+/+ and Cyp1b1-/- mice given Ang II, castration abolished the increased ROS production. In Cyp1b1+/+ mice, 6β-OHT did not alter levels of ROS produced by Ang II, however, 6β-OHT further increased ROS production in Cyp1b1-/- mice given Ang II. These data suggest that 6β-OHT, a CYP1B1 metabolite of testosterone, contributes to the hypertensive effect of Ang II in male mice. Moreover, CYP1B1 could serve as a novel target for the development of agents for the treatment of androgen-mediated hypertension.

Abstract P617: Angiotensin II-induced Hypertension And Vascular Injury Is Mediated By Gamma/delta T Cells

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Antoine Caillon ◽  
Muhammad Oneeb Rehman Mian ◽  
Tlili Barhoumi ◽  
Pierre Paradis ◽  
Ernesto L. Schiffrin
Keyword(s):  
Blood Pressure ◽  
T Cells ◽  
T Cell ◽  
Vascular Injury ◽  
Mesenteric Artery ◽  
Gamma Delta T Cells ◽  
Ang Ii ◽  
Wild Type ◽  
Gamma Delta ◽  
Adaptive Immune

Objective: Both innate antigen presenting cells and the adaptive immune system have been shown to play a role in the development of hypertension. Nevertheless, the T cell subset involved in the pathophysiology of hypertension remains unclear. There is a small subset of “innate-like” T cells expressing gamma/delta T cell receptor (TCR) rather than the alpha/beta TCR that could play a role in bridging between the innate and adaptive immune systems. However, it is unknown whether gamma/delta T cells contribute to development of hypertension. Method/Results: Thirteen to 15 week-old male C57BL/6 wild-type and Tcrd-/- mice, which are devoid of gamma/delta T cells, were infused or not with angiotensin (Ang) II (490 ng/kg/min, SC) for 7 or 14 days (n=4-9). Telemetric blood pressure, mesenteric artery endothelial function and vascular remodeling by pressurized myography and spleen T cell profile by flow cytometry were evaluated. Fourteen days of Ang II increased systolic blood pressure (167±4 vs 125±2 mmHg, P≤0.01) in wild-type compared to control mice. The frequency of gamma/delta T cells (6±1% vs 3±1%, P≤0.05) and activated (CD69+) gamma/delta T cells (11±1% vs 7±1%) was increased after 7 days of Ang II, and 7 days later were respectively unchanged or further increased (24±2% vs 10±1%) in wild-type compared to control mice. Ang II decreased mesenteric artery relaxation responses to acetylcholine (51±5% vs 88±3%, P≤0.01) and increased media/lumen (5±1 vs 3±0%, P≤0.01) in wild-type mice compare to controls. No gamma/delta T cells were detected in Tcrd-/- treated or not with Ang II. All the above Ang II effects were abrogated in Tcrd-/- mice. Conclusion: These data suggest that gamma/delta T cells mediate Ang II-induced blood pressure rise and vascular injury. Gamma/delta T cells could be key immune cells bridging innate and adaptive immune responses during the development of hypertension.

scholarly journals Hypertension in response to CD4+ T cells from reduced uterine perfusion pregnant rats is associated with activation of the endothelin-1 system

2012 ◽  
Vol 303 (2) ◽  
pp. R144-R149 ◽  
Author(s):  
Kedra Wallace ◽  
Sarah Novotny ◽  
Judith Heath ◽  
Janae Moseley ◽  
James N. Martin ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Adoptive Transfer ◽  
Rat Serum ◽  
Pregnant Rats ◽  
Endothelin 1 ◽  
Induced Hypertension ◽  
Uterine Perfusion ◽  
Placental Ischemia

We have shown that adoptive transfer of CD4+ T cells from placental ischemia (reduction in uteroplacental perfusion, RUPP) rats causes hypertension and elevated inflammatory cytokines during pregnancy. In this study we tested the hypothesis that adoptive transfer of RUPP CD4+ T cells was associated with endothelin-1 activation as a mechanism to increase blood pressure during pregnancy. CD4+ T cells from RUPP or normal pregnant (NP) rats were adoptively transferred into NP rats on gestational day 13. Mean arterial pressure (MAP) was analyzed on gestational day 19, and tissues were collected for endothelin-1 analysis. MAP increased in placental ischemic RUPP rats versus NP rats (124.1 ± 3 vs. 96.2 ± 3 mmHg; P = 0.0001) and increased in NP recipients of RUPP CD4+ T cells (117.8 ± 2 mmHg; P = 0.001 compared with NP). Adoptive transfer of RUPP CD4+ T cells increased placental preproendothelin-1 mRNA 2.1-fold compared with NP CD4+ T cell rats and 1.7-fold compared with NP. Endothelin-1 secretion from endothelial cells exposed to NP rat serum was 52.2 ± 1.9 pg·mg−1·ml−1, 77.5 ± 4.3 pg·mg−1·ml−1 with RUPP rat serum ( P = 0.0003); 47.2 ± .16 pg·mg−1·ml−1 with NP+NP CD4+ T cell serum, and 62.2 ± 2.1 pg·mg−1·ml−1 with NP+RUPP CD4+ T cell serum ( P = 0.002). To test the role of endothelin-1 in RUPP CD4+ T cell-induced hypertension, pregnant rats were treated with an endothelin A (ETA) receptor antagonist (ABT-627, 5 mg/kg) via drinking water. MAP was 92 ± 2 mmHg in NP+ETA blockade and 108 ± 3 mmHg in RUPP+ETA blockade; 95 ± 5 mmHg in NP+NP CD4+ T cells+ETA blockade and 102 ± 2 mmHg in NP+RUPP CD4+ T cells+ETA blockade. These data indicate the importance of endothelin-1 activation to cause hypertension via chronic exposure to activated CD4+ T cells in response to placental ischemia.

scholarly journals Endothelial-T cell crosstalk contributes to vascular injury in fatty liver disease

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
C Cheung ◽  
C Y Ng ◽  
K L Lee ◽  
K X Wu ◽  
F W J Chioh ◽  
...  
Keyword(s):  
T Cells ◽  
Endothelial Cells ◽  
Liver Disease ◽  
T Cell ◽  
Endothelial Dysfunction ◽  
Vascular Injury ◽  
Fatty Liver Disease ◽  
Healthy Controls ◽  
Cell Chemotaxis ◽  
Cell Crosstalk

Abstract   Cardiovascular complications are often the fundamental causes of death in non-alcoholic fatty liver disease (NAFLD) patients. While there are known systemic mediators in NAFLD that may induce vascular inflammation, the mechanism of endothelial dysfunction remain understudied. In this work, we harnessed the replicative potential of blood outgrowth endothelial cells (BOECs) to develop personalized cell lines from NAFLD patients and healthy controls. Our transcriptomic analysis showed that the top interactome network enriched in NAFLD BOECs comprised of several C-C and C-X-C chemokine ligands involved in immune cell chemotaxis. We previously reported T cell infiltration in mouse model of non-alcoholic steatohepatitis, and here, we confirmed enhanced endothelial chemokine signatures in arterial histological sections. To elucidate endothelial-immune crosstalk, we performed single-cell analysis on human peripheral blood mononuclear cells and found T cell intensification in NAFLD patients compared to healthy controls. Our immunoprofiling by flow cytometry further revealed that NAFLD patients possessed higher levels CD8+ memory cells. Functionally, T cells, instead of monocytes, adhered more pronouncedly to NAFLD BOECs. In evaluating the CXCL12-CXCR4 axis in chemotaxis, CXCR4 antagonist (AMD3100) substantially modulated the migration of patient-derived CD8+ T cells towards NAFLD BOECs, which was not observed in healthy endothelial-T cell chemotaxis coculture. Finally, we validated NAFLD-associated endothelial dysfunction by enumerating two folds more circulating endothelial cells, a biomarker of vascular injury, in the blood samples of NAFLD patients than healthy controls. Our work provides insights for translation to restore blood vessel health and potentially mitigate adverse vascular events in NAFLD. FUNDunding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Industrial Alignment Fund Pre-Positioning grant from the Agency for Science, Technology and Research, Singapore Endothelial-T cell crosstalk in NAFLD

Abstract P220: Matrix Metalloproteinase 2 Knockout Protects from Angiotensin II-induced Vascular Injury

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Julio C Fraulob-Aquino ◽  
Tlili Barhoumi ◽  
Muhammad O Mian ◽  
Noureddine Idris-Khodja ◽  
Ku-Geng Huo ◽  
...  
Keyword(s):  
T Cells ◽  
Vascular Injury ◽  
Mesenteric Arteries ◽  
Matrix Metalloproteinase 2 ◽  
Ang Ii ◽  
Wild Type ◽  
Vascular Cell ◽  
Induced Hypertension ◽  
Relationship Of ◽  
Transplantation Experiments

Objective: Matrix metalloproteinase-2 (MMP2) participates in the mechanisms of vascular injury in atherosclerosis. Whether MMP2 plays a role in angiotensin (Ang) II-induced hypertension and vascular remodeling is unknown. We hypothesized that Mmp2 knockout ( Mmp2 -/- ) would prevent Ang II-induced hypertension and vascular injury. Methods and Results: Fourteen days of Ang II infusion (1000 ng/kg/min, SC) increased systolic blood pressure (SBP, 161±9 vs 122±3 mm Hg, P <0.05) and decreased vasodilatory responses to acetylcholine (33±5 vs 83±3%, P <0.001), increased the media/lumen (4.8±0.4 vs 3.1±0.1%, P <0.001) and media cross-sectional area (7223±467 vs 5346±336 μm 2 , P <0.05) and enhanced stiffness ( P <0.05), as shown by a leftward shift of the stress/strain relationship of mesenteric arteries in wild-type mice. Ang II enhanced aortic (73±6 vs 6±1 relative fluorescence units [RFU]/μm 2 , P <0.001) and perivascular adipose tissue (PVAT) reactive oxygen species generation (76±11 vs 12±1 RFU/μm 2 , P <0.001), aortic VCAM-1 (17±3 vs 5±1 RFU/μm 2 , P <0.001) and MCP-1 expression (71±14 vs 11±3 RFU/μm 2 , P <0.001), PVAT monocyte/macrophage (1.8±0.3 vs 0.1±0.1 % of PVAT, P <0.001) and T cell infiltration (56±14 vs 16±9 cells/μm 2 , P <0.05) and the fraction of spleen activated CD4 + CD69 + (17±2 vs 10±1 % of CD4+ T cells, P <0.001), CD8 + CD69 + T cells (11±1 vs 5±1 % of CD4+ T cells, P <0.001) and Ly-6C hi monocytes (53±6 vs 25±2 % event, P <0.001). Ang II increased phosphorylation of epidermal growth factor receptor 1.9±0.2-fold and extracellular-signal-regulated kinase 1/2 1.4±0.1-fold in vascular smooth muscle cells isolated from mesenteric arteries of wild-type mice ( P <0.05). Mmp2 knockout prevented or reduced all of the above ( P <0.05) except SBP elevation. Bone marrow transplantation experiments revealed that Ang II-induced hypertension was impaired in absence of immune cell MMP2 and endothelial dysfunction was blunted or reduced in absence of immune or vascular cell MMP2 ( P <0.05). Conclusions: Mmp2 knockout prevented Ang II-induced vascular injury but not hypertension. Bone marrow transplantation experiments revealed a complex relationship of immune and vascular cell MMP2 in the development of Ang II-induced hypertension and endothelial dysfunction.

Abstract 083: γ/δ T Cells Play a Role in Development of Hypertension

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Antoine Caillon ◽  
Muhammad O Mian ◽  
Julio C Fraulob-Aquino ◽  
Ku-Geng Huo ◽  
Tlili Barhoumi ◽  
...  
Keyword(s):  
Gene Expression ◽  
T Cells ◽  
T Cell ◽  
Vascular Injury ◽  
Inflammatory Markers ◽  
Supervised Machine Learning ◽  
T Cell Subsets ◽  
Ang Ii ◽  
Adaptive Immune

Objective: Both innate antigen-presenting cells and the adaptive immune system have been shown to play a role in the development of hypertension. Nevertheless, the T cell subsets involved in the pathophysiology of hypertension remains unclear. There is a small subset of “innate-like” T cells expressing the γ/δ T cell receptor (TCR) rather than the α/β TCR that could play a role bridging the innate and adaptive immune systems. We previously observed that angiotensin (Ang) II caused an increase in number and activation of γ/δ T cells and Ang II-induced systolic blood pressure (SBP) rise and vascular injury were blunted in Tcr δ -/- mice, which are devoid of γ/δ T cells. In order to further characterize the role of γ/δ T cells in hypertension, we determined whether Ang II-effects would be blunted by antibody-induced depletion of γ/δ T cells. In addition, we tested whether SBP in human could be predicted by combining the expression of genes encoding TCRGC (TCR gamma constant region) and pro-inflammatory markers of γ/δ T cells in peripheral blood mononuclear cells (PBMC). Method and Results: Thirteen to 15-week old male C57BL/6 wild-type (WT) mice were infused with Ang II (490 ng/kg/min, SC) for 14 days and injected IP with anti-γ/δ TCR or control isotype antibodies 1 day before and at day 6 of Ang II infusion. Depletion of γ/δ T cells decreased SBP (147±2 vs 167 ± 3 mm Hg, P <0.05) and restored mesenteric artery relaxation responses to acetylcholine (E max : 90±4 vs 62 ± 8%, P <0.05) compared to isotype antibody-treated mice. Using the SBP data and the PBMC gene expression profile (GSE12288) of 222 human subjects, we predicted with a supervised machine learning approach SBP by combining the gene expression of TCRGC and pro-inflammatory makers including interleukin-17A, interferon-γ and their receptors (R=0.23, P <0.001). Conclusion: Antibody-induced depletion further demonstrates the role of γ/δ T cells in Ang II-induced SBP elevation and vascular injury. Prediction of SBP using PBMC gene expression of γ/δ T cells and pro-inflammatory markers suggests that γ/δ T cells contribute to the development of human hypertension.

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