scholarly journals Characterization of Mitochondrial Bioenergetics in Preeclampsia

2021 ◽  
Vol 10 (21) ◽  
pp. 5063
Author(s):  
Ramana Vaka ◽  
Evangeline Deer ◽  
Mark Cunningham ◽  
Kristen M. McMaster ◽  
Kedra Wallace ◽  
...  

Preeclampsia (PE) is characterized by new onset hypertension during pregnancy and is associated with oxidative stress, placental ischemia, and autoantibodies to the angiotensin II type I receptor (AT1-AA). Mitochondrial (mt) dysfunction in PE and various sources of oxidative stress, such as monocytes, neutrophils, and CD4 + T cells, have been identified as important players in the pathophysiology of PE. We have established the significance of AT1-AA, TNF-α, and CD4 + T cells in causing mitochondrial (mt) dysfunction in renal and placental tissues in pregnant rats. Although the role of mt dysfunction from freshly isolated intact placental mitochondria has been compared in human PE and normally pregnant (NP) controls, variations among preterm PE or term PE have not been compared and mechanisms contributing to mt ROS during PE are unclear. Therefore, we hypothesized PE placentas would exhibit impaired placental mt function, which would be worse in preterm PE patients than in those of later gestational ages. Immediately after delivery, PE and NP patient’s placentas were collected, mt were isolated and mt respiration and ROS were measured. PE patients at either < or >34 weeks gestational age (GA) exhibited elevated blood pressure and decreased placental mt respiration rates (state 3 and maximal). Patients delivering at >34 weeks exhibited decreased Complex IV activity and expression. Placental mtROS was significantly reduced in both PE groups, compared to NP placental mitochondria. Collectively, the study demonstrates that PE mt dysfunction occurs in the placenta, with mtROS being lower than that seen in NP controls. These data indicate why antioxidants, as a potential target or new therapeutic agent, may not be ideal in treating the oxidative stress associated with PE.

2015 ◽  
Vol 309 (8) ◽  
pp. R884-R891 ◽  
Author(s):  
Denise C. Cornelius ◽  
Lorena M. Amaral ◽  
Ashlyn Harmon ◽  
Kedra Wallace ◽  
Alexia J. Thomas ◽  
...  

The reduced uterine perfusion pressure (RUPP) rat model of preeclampsia exhibits much of the pathology characterizing this disease, such as hypertension, inflammation, suppressed regulatory T cells (TRegs), reactive oxygen species (ROS), and autoantibodies to the ANG II type I receptor (AT1-AA) during pregnancy. The objective of this study was to determine whether supplementation of normal pregnant (NP) TRegs into RUPP rats would attenuate the pathophysiology associated with preeclampsia during pregnancy. CD4+/CD25+ T cells were isolated from spleens of NP and RUPP rats, cultured, and injected into gestation day (GD) 12 normal pregnant rats that underwent the RUPP procedure on GD 14. On GD 1, mean arterial pressure (MAP) was recorded, and blood and tissues were collected for analysis. One-way ANOVA was used for statistical analysis. MAP increased from 99 ± 2 mmHg in NP ( n = 12) to 127 ± 2 mmHg in RUPP ( n = 21) but decreased to 118 ± 2 mmHg in RUPP+NP TRegs ( n = 17). Circulating IL-6 and IL-10 were not significantly changed, while circulating TNF-α and IL-17 were significantly decreased after supplementation of TRegs. Placental and renal ROS were 339 ± 58.7 and 603 ± 88.1 RLU·min−1·mg−1 in RUPP and significantly decreased to 178 ± 27.8 and 171 ± 55.6 RLU·min−1·mg−1, respectively, in RUPP+NP TRegs; AT1-AA was 17.81 ± 1.1 beats per minute (bpm) in RUPP but was attenuated to 0.50 ± 0.3 bpm with NP TRegs. This study demonstrates that NP TRegs can significantly improve inflammatory mediators, such as IL-17, TNF-α, and AT1-AA, which have been shown to increase blood pressure during pregnancy.


2015 ◽  
Vol 309 (10) ◽  
pp. R1243-R1250 ◽  
Author(s):  
Denise C. Cornelius ◽  
Javier Castillo ◽  
Justin Porter ◽  
Lorena M. Amaral ◽  
Nathan Campbell ◽  
...  

Preeclampsia (PE) is associated with altered immune activation during pregnancy. We have previously shown that adoptive transfer of CD4+ T cells from the reduced uterine perfusion pressure (RUPP) rat model of PE increases blood pressure, oxidative stress (ROS), and inflammation in normal pregnant recipient rats. The objective of this study was to determine if blockade of communication via the CD40-CD40 ligand (CD40L) interaction between placental ischemia-induced CD4+ T cells with endogenous normal pregnant (NP) cells would improve pathophysiology that was previously observed in NP recipient rats of RUPP CD4+ T cells. Splenic CD4+ T lymphocytes were magnetically separated, incubated with 2.5 μg/ml anti-CD40 ligand (αCD40L) overnight, and transferred into NP rats on day 12 of gestation (NP+RUPP CD4+ T+anti-CD40L). On day 19 of gestation, blood pressure (MAP), blood, and tissues were collected. MAP was 99 ± 2 in NP ( n = 13), 116 ± 4 in NP+RUPP CD4+ T cells ( n = 7; P < 0.01); MAP only increased to 104 ± 2 in NP+RUPP CD4+ T cells+CD40L ( n = 24) ( P < 0.05 vs. NP+RUPP CD4+ T cells). Mechanisms of hypertension in response to RUPP CD4+ T cells include endothelin-1 (ET-1), ROS, and angiotensin II type I receptor (AT1-AA) were analyzed. Inhibition of CD40L binding reduced placental ET-1 to 2.3-fold above NP rats and normalized placental ROS from 318.6 ± 89 in NP+RUPP CD4+ T cells ( P < 0.05) to 118.7 ± 24 in NP+RUPP CD4+ T+anti-CD40L ( P < 0.05). AT1-AA was also normalized with inhibition of CD40L. These data suggest that placental ischemia-induced T-cell communication via the CD40L is one important mechanism leading to much of the pathophysiology of PE.


2020 ◽  
Vol 318 (4) ◽  
pp. H1018-H1027 ◽  
Author(s):  
Jeremy W. Duncan ◽  
Subhi Talal Younes ◽  
Emily Hildebrandt ◽  
Michael J. Ryan ◽  
Joey P. Granger ◽  
...  

Preeclampsia is a pregnancy-related disorder characterized by hypertension, vascular dysfunction and an increase in circulating inflammatory factors including the cytokine, tumor necrosis factor-α (TNF-α). Studies have shown that placental ischemia is associated with 1) increased circulating TNF-α, 2) attenuated pressure-induced cerebral vascular tone, and 3) suppression of β-epithelial Na+ channel (βENaC) protein in cerebral vessels. In addition to its role in epithelial Na+ and water transport, βENaC is an essential signaling element in transduction of pressure-induced (aka “myogenic”) constriction, a critical mechanism of blood flow autoregulation. While cytokines inhibit expression of certain ENaC proteins in epithelial tissue, it is unknown if the increased circulating TNF-α associated with placental ischemia mediates the loss of cerebrovascular βENaC and cerebral blood flow regulation. Therefore, the purpose of this study was to test the hypothesis that increasing plasma TNF-α in normal pregnant rats reduces cerebrovascular βENaC expression and impairs cerebral blood flow (CBF) regulation. In vivo TNF-α infusion (200 ng/day, 5 days) inhibited cerebrovascular expression of βENaC and impaired CBF regulation in pregnant rats. To determine the direct effects of TNF-α and underlying pathways mediating vascular smooth muscle cell βENaC reduction, we exposed cultured VSMCs (A10 cell line) to TNF-α (1–100 ng/mL) for 16–24 h. TNF-α reduced βENaC protein expression in a concentration-dependent fashion from 0.1 to 100 ng/mL, without affecting cell death. To assess the role of canonical MAPK signaling in this response, VSMCs were treated with p38MAPK or c-Jun kinase (JNK) inhibitors in the presence of TNF-α. We found that both p38MAPK and JNK blockade prevented TNF-α-mediated βENaC protein suppression. These data provide evidence that disorders associated with increased circulating TNF-α could lead to impaired cerebrovascular regulation, possibly due to reduced βENaC-mediated vascular function. NEW & NOTEWORTHY This manuscript identifies TNF-α as a possible placental-derived cytokine that could be involved in declining cerebrovascular health observed in preeclampsia. We found that infusion of TNF-α during pregnancy impaired cerebral blood flow control in rats at high arterial pressures. We further discovered that cerebrovascular β-epithelial sodium channel (βENaC) protein, a degenerin protein involved in mechanotransduction, was reduced by TNF-α in pregnant rats, indicating a potential link between impaired blood flow and this myogenic player. We next examined this effect in vitro using a rat vascular smooth muscle cell line. TNF-α reduced βENaC through canonical MAPK-signaling pathways and was not dependent on cell death. This study demonstrates the pejorative effects of TNF-α on cerebrovascular function during pregnancy and warrants future investigations to study the role of cytokines on vascular function during pregnancy.


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Kunlong Xiong ◽  
Jinxia Niu ◽  
Ruijuan Zheng ◽  
Zhonghua Liu ◽  
Yanzheng Song ◽  
...  

β-Catenin is a key molecule of canonical Wnt/β-catenin pathway. Its roles and expression profiles in T cells of tuberculosis (TB) remain unclear. The aim of this study was to explore the role of β-catenin in CD4+ T cells and its expression characteristics in patients with pulmonary tuberculosis (PTB). In this study, CD4+ T cell-specific β-catenin conditional knockout mice (β-CAT-cKO mice) were aerosol infected with Mycobacteria tuberculosis (Mtb) H37RV with wild-type mice as controls. Four weeks after infection, the mRNA expression of IFN-γ, TNF-α, and TCF-7 in the lungs of mice was measured. CD4, CD8, β-catenin, IFN-γ, and TNF-α in mononuclear cells from the lungs and spleens were measured by flow cytometry, and the pathological changes of lungs were also observed. Patients with PTB were enrolled, with blood samples collected and PBMCs isolated. The expressions of β-catenin, IFN-γ, TNF-α, and PD-1 in CD4+ and CD8+ T cells were measured by flow cytometry. Results showed a decreased frequency of and reduced IFN-γ/TNF-α mRNA expression and secretion by CD4+ T cells in the lungs of infected β-CAT-cKO mice compared with infected wild-type controls, and only slightly more inflammatory changes were observed in the lungs. β-catenin expressions in CD4+ and CD8+ T cells were significantly decreased in blood cells of patients with severe PTB compared with those in mild PTB. The stimulation of peripheral blood mononuclear cells (PBMCs) with lithium chloride (LiCl), a stimulant of β-catenin, resulted in the increase in CD4+ T cell frequency, as well as their secretion of IFN-γ and TNF-α. β-Catenin demonstrated a moderately positive correlation with PD-1 in CD4+ T cells. β-Catenin along with PD-1 and IFN-γ in CD4+ T cells had a high correlation with those in CD8+ T cells. In conclusion, β-catenin may be involved in the regulation of Th1 response and CD4+ T cell frequency in TB.


2015 ◽  
Vol 309 (11) ◽  
pp. R1425-R1431 ◽  
Author(s):  
Junie P. Warrington ◽  
Heather A. Drummond ◽  
Joey P. Granger ◽  
Michael J. Ryan

Cerebrovascular complications and increased risk of encephalopathies are characteristic of preeclampsia and contribute to 40% of preeclampsia/eclampsia-related deaths. Circulating tumor necrosis factor-α (TNF-α) is elevated in preeclamptic women, and infusion of TNF-α into pregnant rats mimics characteristics of preeclampsia. While this suggests that TNF-α has a mechanistic role to promote preeclampsia, the impact of TNF-α on the cerebral vasculature during pregnancy remains unclear. We tested the hypothesis that TNF-α contributes to cerebrovascular abnormalities during placental ischemia by first infusing TNF-α in pregnant rats (200 ng/day ip, from gestational day 14 to 19) at levels to mimic those reported in preeclamptic women. TNF-α increased mean arterial pressure (MAP, P < 0.05) and brain water content in the anterior cerebrum ( P < 0.05); however, TNF-α infusion had no effect on blood-brain barrier (BBB) permeability in the anterior cerebrum or posterior cerebrum. We then assessed the role of endogenous TNF-α in mediating these abnormalities in a model of placental ischemia induced by reducing uterine perfusion pressure followed by treatment with the soluble TNF-α receptor (etanercept, 0.8 mg/kg sc) on gestational day 18. Etanercept reduced placental ischemia-mediated increases in MAP, anterior brain water content ( P < 0.05), and BBB permeability (202 ± 44% in placental ischemic rats to 101 ± 28% of normal pregnant rats). Our results indicate that TNF-α mechanistically contributes to cerebral edema by increasing BBB permeability and is an underlying factor in the development of cerebrovascular abnormalities associated with preeclampsia complicated by placental ischemia.


Hypertension ◽  
2020 ◽  
Vol 76 (Suppl_1) ◽  
Author(s):  
Evangeline M Deer ◽  
Kristin Reeve ◽  
Lorena M Amaral ◽  
Venkata Ramana Vaka ◽  
Michael Franks ◽  
...  

Preeclampsia (PE) is new onset hypertension during pregnancy and is associated with elevated inflammatory response such as CD4+ T cells, NK cells, and cytokines. We have previously shown women with PE exhibit increases in circulating and placental CD4+T cells and placental mitochondrial (mt) dysfunction/ROS compared to normal pregnant (NP) women. The Reduced Uterine Perfusion Pressure (RUPP) rat model produces many characteristics of PE such as hypertension, increases in CD4+ cells, increases in renal and placental NK cells, and mt dysfunction/ROS. We have previously demonstrated that RUPP CD4+T cells cause hypertension in NP rats, however the role of RUPP CD4+ T cells in stimulating NK cells to cause mt dysfunction/ROS are not elucidated. Therefore, we examined the effect of adoptive transfer of RUPP CD4+ T cells to activate NK cells in NP rats. Splenic CD4+ T cells were isolated from RUPP rats, cultured, and injected into NP rats on GD 13. On GD19, MAP values and blood/tissue samples were collected from both RUPP CD4+ T cell recipients and NP controls. Mitochondrial respiration and mtROS were measured in isolated mitochondria using the Oxygraph 2K and fluorescent microplate reader, respectively. A student’s t-test was used for statistical analysis. On GD19, MAP increased to 110±2 mmHg (n=13) in RUPP CD4+ T cell recipients compared to control NP rats 102±2 mmHg (n=7, p<0.05). Circulating cytolytic NK cells increased to 3±0.6% in RUPP CD4+ T cell recipients (n=8) compared to NP controls 0.3±0.2% (n=7, p<0.05). Placental state 3 (209.3±31.3 vs 422.7 ±83.3 pmol/sec/mg, p<0.05) and maximal (152.1±46.2 vs 229.7±58.9 pmol/sec/mg) and renal state 3 (133.4 ±21.4 vs 289.8±43.4 pmol/sec/mg, p<0.05) and maximal (61.8±18 vs 242.4±27.7 pmol/sec/mg, p<0.05) respiration rates, indicative of ATP production and electron transport chain efficacy respectively, were reduced with RUPP CD4+ T cells (n=6; n=9) compared to NP (n=5; n=5). Collectively, the data indicate that the adoptive transfer of RUPP CD4+ T cells stimulates cytolytic NK cells and placental and renal mitochondrial dysfunction/ROS during pregnancy as important mechanisms of hypertension in the pathophysiology of preeclampsia. Keywords: Preeclamspia, Hypertension, Oxidative stress


2012 ◽  
Vol 303 (2) ◽  
pp. R144-R149 ◽  
Author(s):  
Kedra Wallace ◽  
Sarah Novotny ◽  
Judith Heath ◽  
Janae Moseley ◽  
James N. Martin ◽  
...  

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.


2013 ◽  
Vol 304 (2) ◽  
pp. R130-R135 ◽  
Author(s):  
Sydney R. Murphy ◽  
B. Babbette D. LaMarca ◽  
Marc Parrish ◽  
Kathy Cockrell ◽  
Joey P. Granger

Although abnormal soluble fms-like tyrosine kinase-1 (sFlt-1) production is thought to be an important factor in the pathogenesis of preeclampsia (PE), the mechanisms that regulate the production of sFlt-1 during PE are unclear. While our laboratory has shown tumor necrosis factor-α (TNF-α) and sFlt-1 to be elevated in pregnant rats in response to placental ischemia, the importance of TNF-α in the regulation of sFlt-1 production is unknown. Therefore, the purpose of this study was to determine the role of TNF-α in mediating the increase in sFlt-1 in response to placental ischemia or hypoxia. Reductions in uterine perfusion pressure in pregnant rats significantly increased plasma levels of sFlt-1 and tended to increase TNF-α, an effect markedly attenuated by pretreatment with a TNF-α inhibitor etanercept (0.4 mg/kg). To further assess chronic interactions between TNF-α and sFlt-1, we examined a chronic effect of TNF-α infusion (50 ng/day) into normal pregnant rats to increase plasma sFlt-1 levels, as well as the effects of acute hypoxia on placental sFlt-1 production in the absence and presence of TNF-α blockade. Placental explants exposed to hypoxic conditions had enhanced TNF-α levels versus normoxic conditions, as well as increased sFlt-1 production. Pretreatment of placental explants with etanercept (15 μM) significantly reduced TNF-α levels in response to hypoxia but did not attenuate sFlt-1 production. These data suggest that while TNF-α may not play an important role in stimulating sFlt-1 production in response to acute hypoxia, a more chronic hypoxia, or placental ischemia may be an important stimulus for enhanced sFlt-l production.


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