1
|
Govatati S, Kumar R, Boro M, Traylor JG, Orr AW, Lusis AJ, Rao GN. TRIM13 reduces cholesterol efflux and increases oxidized LDL uptake leading to foam cell formation and atherosclerosis. J Biol Chem 2024; 300:107224. [PMID: 38537695 PMCID: PMC11053335 DOI: 10.1016/j.jbc.2024.107224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 03/11/2024] [Accepted: 03/13/2024] [Indexed: 04/25/2024] Open
Abstract
Impaired cholesterol efflux and/or uptake can influence arterial lipid accumulation leading to atherosclerosis. Here, we report that tripartite motif-containing protein 13 (TRIM13), a RING-type E3 ubiquitin ligase, plays a role in arterial lipid accumulation leading to atherosclerosis. Using molecular approaches and KO mouse model, we found that TRIM13 expression was induced both in the aorta and peritoneal macrophages (pMφ) of ApoE-/- mice in response to Western diet (WD) in vivo. Furthermore, proatherogenic cytokine interleukin-1β also induced TRIM13 expression both in pMφ and vascular smooth muscle cells. Furthermore, we found that TRIM13 via ubiquitination and degradation of liver X receptor (LXR)α/β downregulates the expression of their target genes ABCA1/G1 and thereby inhibits cholesterol efflux. In addition, TRIM13 by ubiquitinating and degrading suppressor of cytokine signaling 1/3 (SOCS1/3) mediates signal transducer and activator of transcription 1 (STAT1) activation, CD36 expression, and foam cell formation. In line with these observations, genetic deletion of TRIM13 by rescuing cholesterol efflux and inhibiting foam cell formation protects against diet-induced atherosclerosis. We also found that while TRIM13 and CD36 levels were increased, LXRα/β, ABCA1/G1, and SOCS3 levels were decreased both in Mφ and smooth muscle cells of stenotic human coronary arteries as compared to nonstenotic arteries. More intriguingly, the expression levels of TRIM13 and its downstream signaling molecules were correlated with the severity of stenotic lesions. Together, these observations reveal for the first time that TRIM13 plays a crucial role in diet-induced atherosclerosis, and that it could be a potential drug target against this vascular lesion.
Collapse
Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Monoranjan Boro
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - James G Traylor
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, Louisiana, USA
| | - A Wayne Orr
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, Louisiana, USA
| | - Aldons J Lusis
- Division of Cardiology, Department of Medicine, University of California, Los Angeles, California, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA.
| |
Collapse
|
2
|
Kumar R, Rottner K, Rao GN. Requirement of Site-Specific Tyrosine Phosphorylation of Cortactin in Retinal Neovascularization and Vascular Leakage. Arterioscler Thromb Vasc Biol 2024; 44:366-390. [PMID: 38126170 PMCID: PMC10872470 DOI: 10.1161/atvbaha.123.320279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 12/06/2023] [Indexed: 12/23/2023]
Abstract
BACKGROUND Retinal neovascularization is a major cause of vision impairment. Therefore, the purpose of this study is to investigate the mechanisms by which hypoxia triggers the development of abnormal and leaky blood vessels. METHODS A variety of cellular and molecular approaches as well as tissue-specific knockout mice were used to investigate the role of Cttn (cortactin) in retinal neovascularization and vascular leakage. RESULTS We found that VEGFA (vascular endothelial growth factor A) stimulates Cttn phosphorylation at Y421, Y453, and Y470 residues in human retinal microvascular endothelial cells. In addition, we observed that while blockade of Cttn phosphorylation at Y470 inhibited VEGFA-induced human retinal microvascular endothelial cell angiogenic events, suppression of Y421 phosphorylation protected endothelial barrier integrity from disruption by VEGFA. In line with these observations, while blockade of Cttn phosphorylation at Y470 negated oxygen-induced retinopathy-induced retinal neovascularization, interference with Y421 phosphorylation prevented VEGFA/oxygen-induced retinopathy-induced vascular leakage. Mechanistically, while phosphorylation at Y470 was required for its interaction with Arp2/3 and CDC6 facilitating actin polymerization and DNA synthesis, respectively, Cttn phosphorylation at Y421 leads to its dissociation from VE-cadherin, resulting in adherens junction disruption. Furthermore, whereas Cttn phosphorylation at Y470 residue was dependent on Lyn, its phosphorylation at Y421 residue required Syk activation. Accordingly, lentivirus-mediated expression of shRNA targeting Lyn or Syk levels inhibited oxygen-induced retinopathy-induced retinal neovascularization and vascular leakage, respectively. CONCLUSIONS The above observations show for the first time that phosphorylation of Cttn is involved in a site-specific manner in the regulation of retinal neovascularization and vascular leakage. In view of these findings, Cttn could be a novel target for the development of therapeutics against vascular diseases such as retinal neovascularization and vascular leakage.
Collapse
Affiliation(s)
- Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Klemens Rottner
- Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany
- Department of Cell Biology, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Gadiparthi N. Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
3
|
Govatati S, Pichavaram P, Kumar R, Rao GN. Blockade of CD47 function attenuates restenosis by promoting smooth muscle cell efferocytosis and inhibiting their migration and proliferation. J Biol Chem 2023; 299:104594. [PMID: 36898577 PMCID: PMC10124914 DOI: 10.1016/j.jbc.2023.104594] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/10/2023] Open
Abstract
Cluster of differentiation 47 (CD47) plays an important role in the pathophysiology of various diseases including atherosclerosis, but its role in neointimal hyperplasia which contributes to restenosis, has not been studied. Using molecular approaches in combination with a mouse vascular endothelial denudation model, we studied the role of CD47 in injury-induced neointimal hyperplasia. We determined that thrombin induced CD47 expression both in human and mouse aortic smooth muscle cells (HASMCs and MASMCs). In exploring the mechanisms, we found that the protease-activated receptor 1 (PAR1)-Gα protein q/11 (Gαq/11)-phospholipase Cβ3 (PLCβ3)-nuclear factor of activated T cells c1 (NFATc1) signaling axis regulates thrombin-induced CD47 expression in HASMCs. Depletion of CD47 levels using its siRNA or interference of its function by its blocking antibody (bAb) blunted thrombin-induced migration and proliferation of HASMCs and MASMCs. In addition, we found that thrombin-induced HASMC migration requires CD47 interaction with integrin β3. On the other hand, thrombin-induced HASMC proliferation was dependent on CD47's role in nuclear export and degradation of CDK-interacting protein 1 (p21Cip1). In addition, suppression of CD47 function by its bAb rescued HASMC efferocytosis from inhibition by thrombin. We also found that vascular injury induces CD47 expression in intimal SMCs and that inhibition of CD47 function by its bAb, while alleviating injury-induced inhibition of SMC efferocytosis, attenuated SMC migration and proliferation resulting in reduced neointima formation. Thus, these findings reveal a pathological role for CD47 in neointimal hyperplasia.
Collapse
Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| |
Collapse
|
4
|
Xiong S, Hong Z, Huang LS, Tsukasaki Y, Nepal S, Di A, Zhong M, Wu W, Ye Z, Gao X, Rao GN, Mehta D, Rehman J, Malik AB. IL-1β suppression of VE-cadherin transcription underlies sepsis-induced inflammatory lung injury. J Clin Invest 2023; 133:169500. [PMID: 36856118 PMCID: PMC9974088 DOI: 10.1172/jci169500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023] Open
|
5
|
Dienel A, Hong S, Thomas S, Torres K, Rao GN, Thankamani Pandit P, Blackburn S, McBride D. Abstract WP214: Inhibition Of 12/15-Lipoxygenase Attenuates Delayed Vasospasm After Subarachnoid Hemorrhage In Mice. Stroke 2023. [DOI: 10.1161/str.54.suppl_1.wp214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Approximately 30% of subarachnoid hemorrhage (SAH) patients who survive the initial ictus develop delayed cerebral ischemia (DCI) 4 to 10 days following SAH. Multiple clinical studies indicate the cause of DCI is multifactorial and includes vasospasm. 12/15-Lipoxygenase (LOX), enzymes that metabolize arachidonic acid into bioactive lipid metabolites, such as 12-HETE and 15-HETE, are expressed in several cell types of the brain including neurons, and microglia. Previous work has shown that 12/15-LOX has detrimental effects on brain vasculature and neurons, triggers inflammation, and thrombosis. In a previous study, inhibition of 12/15-LOX was beneficial in reducing early brain injury in mice after SAH. We hypothesize that inhibition of 12/15-LOX would attenuate delay vasospasm and reduce DCI in SAH mice. C57BL/6 mice of both sexes were randomized into Sham+Vehicle, SAH+Vehicle, SAH+ML351. Vehicle and ML351 (LOX inhibitor, 25mg/kg) were intravenously injected 15 minutes after SAH. 12/15-LOX
-/-
mice of both sexes were randomized into sham or SAH. Behavior was assessed daily until euthanasia on day 5 for analysis of vasospasm. Following SAH, there, there was an increased expression of 12/15-LOX in brain endothelial cells. Inhibition of 12/15-LOX in C57BL/6 males reduced large artery vasospasm and microvessel constriction, improved functional outcome, and lowered DCI incidence. In female C57BL/6 mice, inhibition of 12/15-LOX also reduced vasospasm and microvessel constriction, and ameliorated behavioral deficits. 12/15-LOX
-/-
displayed better behavior and have less delayed vasospasm. The findings of this study suggest that inhibition of 12/15-LOX is therapeutically beneficial for male and female mice after SAH via preventing delay vasospasm and DCI.
Collapse
|
6
|
Kotla S, Rao GN. Withdrawal: Reactive oxygen species (ROS) mediate p300-dependent STAT1 protein interaction with peroxisome proliferator-activated receptor (PPAR)-γ in CD36 protein expression and foam cell formation. J Biol Chem 2022; 298:102152. [PMID: 35777196 PMCID: PMC9251776 DOI: 10.1016/j.jbc.2022.102152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
7
|
Sharma D, Bisen S, Kaur G, Van Buren EC, Rao GN, Singh NK. IL-33 enhances Jagged1 mediated NOTCH1 intracellular domain (NICD) deubiquitination and pathological angiogenesis in proliferative retinopathy. Commun Biol 2022; 5:479. [PMID: 35589941 PMCID: PMC9120174 DOI: 10.1038/s42003-022-03432-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/29/2022] [Indexed: 01/10/2023] Open
Abstract
Pathological retinal neovascularization (NV) is a clinical manifestation of various proliferative retinopathies, and treatment of NV using anti-VEGF therapies is not selective, as it also impairs normal retinal vascular growth and function. Here, we show that genetic deletion or siRNA-mediated downregulation of IL-33 reduces pathological NV in a murine model of oxygen-induced retinopathy (OIR) with no effect on the normal retinal repair. Furthermore, our fluorescent activated cell sorting (FACS) data reveals that the increase in IL-33 expression is in endothelial cells (ECs) of the hypoxic retina and conditional genetic deletion of IL-33 in retinal ECs reduces pathological NV. In vitro studies using human retinal microvascular endothelial cells (HRMVECs) show that IL-33 induces sprouting angiogenesis and requires NFkappaB-mediated Jagged1 expression and Notch1 activation. Our data also suggest that IL-33 enhances de-ubiquitination and stabilization of Notch1 intracellular domain via its interaction with BRCA1-associated protein 1 (BAP1) and Numb in HRMVECs and a murine model of OIR.
Collapse
Affiliation(s)
- Deepti Sharma
- Integrative Biosciences Center, Wayne State University, Detroit, MI, 48202, USA
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - Shivantika Bisen
- Integrative Biosciences Center, Wayne State University, Detroit, MI, 48202, USA
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - Geetika Kaur
- Integrative Biosciences Center, Wayne State University, Detroit, MI, 48202, USA
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, 48202, USA
| | - Eric C Van Buren
- Department of Oncology, Wayne State University School of Medicine, Detroit, MI, 48201, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nikhlesh K Singh
- Integrative Biosciences Center, Wayne State University, Detroit, MI, 48202, USA.
- Department of Ophthalmology, Visual and Anatomical Sciences, Wayne State University School of Medicine, Detroit, MI, 48202, USA.
| |
Collapse
|
8
|
Abstract
BACKGROUND The major aim of this study is to investigate whether CDC6 (cell division cycle 6), a replication origin recognition complex component, plays a role in retinal neovascularization, and if so, to explore the underlying mechanisms. METHODS In this study, we used a variety of approaches including cellular and moleculer biological methodologies as well as global and tissue-specific knockout mice in combination with an oxygen-induced retinopathy model to study the role of CDC6 in retinal neovascularization. RESULTS VEGFA (vascular endothelial growth factor A)-induced CDC6 expression in a time-dependent manner in human retinal microvascular endothelial cells. In addition, VEGFA-induced CDC6 expression was dependent on PLCβ3 (phospholipase Cβ3)-mediated NFATc1 (nuclear factor of activated T cells c1) activation. Furthermore, while siRNA-mediated depletion of PLCβ3, NFATc1, or CDC6 levels blunted VEGFA-induced human retinal microvascular endothelial cell angiogenic events such as proliferation, migration, sprouting, and tube formation, CDC6 overexpression rescued these effects in NFATc1-deficient mouse retinal microvascular endothelial cells. In accordance with these observations, global knockdown of PLCβ3 or endothelial cell-specific deletion of NFATc1 or siRNA-mediated depletion of CDC6 levels substantially inhibited oxygen-induced retinopathy-induced retinal sprouting and neovascularization. In addition, retroviral-mediated overexpression of CDC6 rescued oxygen-induced retinopathy-induced retinal neovascularization from inhibition in PLCβ3 knockout mice and in endothelial cell-specific NFATc1-deficient mice. CONCLUSIONS The above observations clearly reveal that PLCβ3-mediated NFATc1 activation-dependent CDC6 expression plays a crucial role in VEGFA/oxygen-induced retinopathy-induced retinal neovascularization.
Collapse
Affiliation(s)
- Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| |
Collapse
|
9
|
Kotla S, Singh NK, Kirchhofer D, Rao GN. Correction: Heterodimers of the transcriptional factors NFATc3 and FosB mediate tissue factor expression for 15(S)-hydroxyeicosatetraenoic acid-induced monocyte trafficking. J Biol Chem 2022; 298:101812. [PMID: 35303608 PMCID: PMC8931423 DOI: 10.1016/j.jbc.2022.101812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
10
|
Kotla S, Singh NK, Rao GN. Corrigendum to “ROS via BTK-p300-STAT1-PPARγ signaling activation mediates cholesterol crystals-induced CD36 expression and foam cell formation” [Redox Biol. 11 (2017) 350–364/513]. Redox Biol 2022; 50:102254. [PMID: 35131205 PMCID: PMC8858724 DOI: 10.1016/j.redox.2022.102254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| |
Collapse
|
11
|
Govatati S, Pichavaram P, Mani AM, Kumar R, Sharma D, Dienel A, Meena S, Puchowicz MA, Park EA, Rao GN. Novel role of xanthine oxidase-dependent H 2O 2 production in 12/15-lipoxygenase-mediated de novo lipogenesis, triglyceride biosynthesis and weight gain. Redox Biol 2021; 47:102163. [PMID: 34655995 PMCID: PMC8577505 DOI: 10.1016/j.redox.2021.102163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Revised: 10/07/2021] [Accepted: 10/07/2021] [Indexed: 11/16/2022] Open
Abstract
12/15-lipoxygenase (12/15-LOX) plays an essential role in oxidative conversion of polyunsaturated fatty acids into various bioactive lipid molecules. Although 12/15-LOX's role in the pathophysiology of various human diseases has been well studied, its role in weight gain is controversial and poorly clarified. Here, we demonstrated the role of 12/15-LOX in high-fat diet (HFD)-induced weight gain in a mouse model. We found that 12/15-LOX mediates HFD-induced de novo lipogenesis (DNL), triglyceride (TG) biosynthesis and the transport of TGs from the liver to adipose tissue leading to white adipose tissue (WAT) expansion and weight gain via xanthine oxidase (XO)-dependent production of H2O2. 12/15-LOX deficiency leads to cullin2-mediated ubiquitination and degradation of XO, thereby suppressing H2O2 production, DNL and TG biosynthesis resulting in reduced WAT expansion and weight gain. These findings infer that manipulation of 12/15-LOX metabolism may manifest a potential therapeutic target for weight gain and obesity. 12/15-LOX-12(S)-HETE axis via activation of CREB-Egr1 enhances TG biosynthesis. 12/15-LOX-12(S)-HETE axis via activation of SREBP1c triggers DNL. H2O2 mediates 12/15-LOX-12(S)-HETE axis-induced DNL and TG biosynthesis. 12/15-LOX via TG biosynthesis leads to WAT expansion and body weight gain. Downstream to 12/15-LOX, H2O2-mediates WAT expansion and body weight gain.
Collapse
Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Deepti Sharma
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Ari Dienel
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Sunita Meena
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Michelle A Puchowicz
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Edwards A Park
- Department of Pharmacology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| |
Collapse
|
12
|
Boro M, Govatati S, Kumar R, Singh NK, Pichavaram P, Traylor JG, Orr AW, Rao GN. Correction: Thrombin-Par1 signaling axis disrupts COP9 signalosome subunit 3-mediated ABCA1 stabilization in inducing foam cell formation and atherogenesis. Cell Death Differ 2021; 28:2303. [PMID: 33437040 DOI: 10.1038/s41418-020-00718-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Monoranjan Boro
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - James G Traylor
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, LA, 71103, USA
| | - A Wayne Orr
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, LA, 71103, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| |
Collapse
|
13
|
Boro M, Govatati S, Kumar R, Singh NK, Pichavaram P, Traylor JG, Orr AW, Rao GN. Thrombin-Par1 signaling axis disrupts COP9 signalosome subunit 3-mediated ABCA1 stabilization in inducing foam cell formation and atherogenesis. Cell Death Differ 2020; 28:780-798. [PMID: 32968199 DOI: 10.1038/s41418-020-00623-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 09/07/2020] [Indexed: 11/09/2022] Open
Abstract
ATP-binding cassette transporters A1 (ABCA1) and G1 (ABCG1) play a vital role in promoting cholesterol efflux. Although, the dysregulation of these transporters was attributed as one of the mechanisms of atherogenesis, what renders their dysfunction is not well explored. Previously, we have reported that thrombin without having any effect on ABCG1 levels depletes ABCA1 levels affecting cholesterol efflux. In this study, we explored the mechanisms underlying thrombin-induced depletion of ABCA1 levels both in macrophages and smooth muscle cells. Under normal physiological conditions, COP9 signalosome subunit 3 (CSN3) was found to exist in complex with ABCA1 and in the presence of proatherogenic stimulants such as thrombin, ABCA1 was phosphorylated and dissociated from CSN3, leading to its degradation. Forced expression of CSN3 inhibited thrombin-induced ABCA1 ubiquitination and degradation, restored cholesterol efflux and suppressed foam cell formation. In Western diet (WD)-fed ApoE-/- mice, CSN3 was also disassociated from ABCA1 otherwise remained as a complex in Chow diet (CD)-fed ApoE-/- mice. Interestingly, depletion of CSN3 levels in WD-fed ApoE-/- mice significantly lowered ABCA1 levels, inhibited cholesterol efflux and intensified foam cell formation exacerbating the lipid laden atherosclerotic plaque formation. Mechanistic studies have revealed the involvement of Par1-Gα12-Pyk2-Gab1-PKCθ signaling in triggering phosphorylation of ABCA1 and its disassociation from CSN3 curtailing cholesterol efflux and amplifying foam cell formation. In addition, although both CSN3 and ABCA1 were found to be colocalized in human non-lesion coronary arteries, their levels were decreased as well as dissociated from each other in advanced atherosclerotic lesions. Together, these observations reveal for the first time an anti-atherogenic role of CSN3 and hence, designing therapeutic drugs protecting its interactions with ABCA1 could be beneficial against atherosclerosis.
Collapse
Affiliation(s)
- Monoranjan Boro
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - James G Traylor
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, LA, 71103, USA
| | - A Wayne Orr
- Department of Pathology, Louisiana State University Health Science Center, Shreveport, LA, 71103, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| |
Collapse
|
14
|
Xiong S, Hong Z, Huang LS, Tsukasaki Y, Nepal S, Di A, Zhong M, Wu W, Ye Z, Gao X, Rao GN, Mehta D, Rehman J, Malik AB. IL-1β suppression of VE-cadherin transcription underlies sepsis-induced inflammatory lung injury. J Clin Invest 2020; 130:3684-3698. [PMID: 32298238 PMCID: PMC7324198 DOI: 10.1172/jci136908] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 04/09/2020] [Indexed: 12/18/2022] Open
Abstract
Unchecked inflammation is a hallmark of inflammatory tissue injury in diseases such as acute respiratory distress syndrome (ARDS). Yet the mechanisms of inflammatory lung injury remain largely unknown. Here we showed that bacterial endotoxin lipopolysaccharide (LPS) and cecal ligation and puncture-induced (CLP-induced) polymicrobial sepsis decreased the expression of transcription factor cAMP response element binding (CREB) in lung endothelial cells. We demonstrated that endothelial CREB was crucial for VE-cadherin transcription and the formation of the normal restrictive endothelial adherens junctions. The inflammatory cytokine IL-1β reduced cAMP generation and CREB-mediated transcription of VE-cadherin. Furthermore, endothelial cell-specific deletion of CREB induced lung vascular injury whereas ectopic expression of CREB in the endothelium prevented the injury. We also observed that rolipram, which inhibits type 4 cyclic nucleotide phosphodiesterase-mediated (PDE4-mediated) hydrolysis of cAMP, prevented endotoxemia-induced lung vascular injury since it preserved CREB-mediated VE-cadherin expression. These data demonstrate the fundamental role of the endothelial cAMP-CREB axis in promoting lung vascular integrity and suppressing inflammatory injury. Therefore, strategies aimed at enhancing endothelial CREB-mediated VE-cadherin transcription are potentially useful in preventing sepsis-induced lung vascular injury in ARDS.
Collapse
Affiliation(s)
- Shiqin Xiong
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Zhigang Hong
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Long Shuang Huang
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Yoshikazu Tsukasaki
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Saroj Nepal
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Anke Di
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Ming Zhong
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Wei Wu
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Zhiming Ye
- Department of Nephrology, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Xiaopei Gao
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Gadiparthi N. Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee, USA
| | - Dolly Mehta
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Jalees Rehman
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| | - Asrar B. Malik
- Department of Pharmacology and Regenerative Medicine and
- Center for Lung and Vascular Biology, University of Illinois College of Medicine, Chicago, Illinois, USA
| |
Collapse
|
15
|
Kumar R, Mani AM, Singh NK, Rao GN. PKCθ-JunB axis via upregulation of VEGFR3 expression mediates hypoxia-induced pathological retinal neovascularization. Cell Death Dis 2020; 11:325. [PMID: 32382040 PMCID: PMC7206019 DOI: 10.1038/s41419-020-2522-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 04/17/2020] [Accepted: 04/20/2020] [Indexed: 12/30/2022]
Abstract
Pathological retinal neovascularization is the most common cause of vision loss. PKCθ has been shown to play a role in type 2 diabetes, which is linked to retinal neovascularization. Based on these clues, we have studied the role of PKCθ and its downstream target genes JunB and VEGFR3 in retinal neovascularization using global and tissue-specific knockout mouse models along with molecular biological approaches. Here, we show that vascular endothelial growth factor A (VEGFA) induces PKCθ phosphorylation in human retinal microvascular endothelial cells (HRMVECs) and downregulation of its levels attenuates VEGFA-induced HRMVECs migration, sprouting and tube formation. Furthermore, the whole body deletion of PKCθ or EC-specific deletion of its target gene JunB inhibited hypoxia-induced retinal EC proliferation, tip cell formation and neovascularization. VEGFA also induced VEGFR3 expression via JunB downstream to PKCθ in the regulation of HRMVEC migration, sprouting, and tube formation in vitro and OIR-induced retinal EC proliferation, tip cell formation and neovascularization in vivo. In addition, VEGFA-induced VEGFR3 expression requires VEGFR2 activation upstream to PKCθ-JunB axis both in vitro and in vivo. Depletion of VEGFR2 or VEGFR3 levels attenuated VEGFA-induced HRMVEC migration, sprouting and tube formation in vitro and retinal neovascularization in vivo and it appears that these events were dependent on STAT3 activation. Furthermore, the observations using soluble VEGFR3 indicate that VEGFR3 mediates its effects on retinal neovascularization in a ligand dependent and independent manner downstream to VEGFR2. Together, these observations suggest that PKCθ-dependent JunB-mediated VEGFR3 expression targeting STAT3 activation is required for VEGFA/VEGFR2-induced retinal neovascularization.
Collapse
Affiliation(s)
- Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| |
Collapse
|
16
|
Govatati S, Pichavaram P, Janjanam J, Guo L, Virmani R, Rao GN. Myristoylation of LMCD1 Leads to Its Species-Specific Derepression of E2F1 and NFATc1 in the Modulation of CDC6 and IL-33 Expression During Development of Vascular Lesions. Arterioscler Thromb Vasc Biol 2020; 40:1256-1274. [PMID: 32160773 PMCID: PMC7180120 DOI: 10.1161/atvbaha.120.314147] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE In view of our previous observations on differential expression of LMCD1 (LIM and cysteine-rich domains 1) in human versus rodents, we asked the question whether LMCD1 plays a species-specific role in the development of vascular lesions. Approach and Results: A combination of genetic, molecular, cellular, and disease models were used to test species-specific role of LMCD1 in the pathogenesis of vascular lesions. Here, we report species-specific regulation of LMCD1 expression in mediating vascular smooth muscle cell proliferation and migration during vascular wall remodeling in humans versus mice. Thrombin induced LMCD1 expression in human aortic smooth muscle cells but not mouse aortic smooth muscle cells via activation of Par1 (protease-activated receptor 1)-Gαq/11 (Gα protein q/11)-PLCβ3 (phospholipase Cβ3)-NFATc1 (nuclear factor of activated T cells 1) signaling. Furthermore, although LMCD1 mediates thrombin-induced proliferation and migration of both human aortic smooth muscle cells and mouse aortic smooth muscle cells via influencing E2F1 (E2F transcription factor 1)-mediated CDC6 (cell division cycle 6) expression and NFATc1-mediated IL (interleukin)-33 expression, respectively, in humans, it acts as an activator, and in mice, it acts as a repressor of these transcriptional factors. Interestingly, LMCD1 repressor activity was nullified by N-myristoyltransferase 2-mediated myristoylation in mouse. Besides, we found increased expression of LMCD1 in human stenotic arteries as compared to nonstenotic arteries. On the other hand, LMCD1 expression was decreased in neointimal lesions of mouse injured arteries as compared to noninjured arteries. CONCLUSIONS Together, these observations reveal that LMCD1 acts as an activator and repressor of E2F1 and NFATc1 in humans and mice, respectively, in the induction of CDC6 and IL-33 expression during development of vascular lesions. Based on these findings, LMCD could be a potential target for drug development against restenosis and atherosclerosis in humans.
Collapse
MESH Headings
- Animals
- Cell Cycle Proteins/genetics
- Cell Cycle Proteins/metabolism
- Cell Movement
- Cell Proliferation
- Cells, Cultured
- Co-Repressor Proteins/genetics
- Co-Repressor Proteins/metabolism
- Disease Models, Animal
- E2F1 Transcription Factor/genetics
- E2F1 Transcription Factor/metabolism
- Female
- Gene Expression Regulation
- Humans
- Interleukin-33/genetics
- Interleukin-33/metabolism
- LIM Domain Proteins/genetics
- LIM Domain Proteins/metabolism
- Male
- Mice, Inbred C57BL
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Myristic Acid/metabolism
- NFATC Transcription Factors/genetics
- NFATC Transcription Factors/metabolism
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Protein Processing, Post-Translational
- Signal Transduction
- Species Specificity
- Thrombin/pharmacology
- Vascular Remodeling/drug effects
- Vascular System Injuries/genetics
- Vascular System Injuries/metabolism
- Vascular System Injuries/pathology
Collapse
Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health
Science Center, Memphis, TN 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health
Science Center, Memphis, TN 38163, USA
| | - Jagadeesh Janjanam
- Department of Physiology, University of Tennessee Health
Science Center, Memphis, TN 38163, USA
| | - Liang Guo
- CVPath Institute Inc., Gaithersburg, MD 20878
| | | | - Gadiparthi N. Rao
- Department of Physiology, University of Tennessee Health
Science Center, Memphis, TN 38163, USA
| |
Collapse
|
17
|
Kumar R, Mani AM, Singh NK, Rao GN. PKCθ‐JunB axis via upregulation of VEGFR3 expression mediates VEGFR2‐induced pathological retinal neovascularization. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Raj Kumar
- University of Tennessee Health Science Center
| | | | | | | |
Collapse
|
18
|
Govatati S, Pichavaram P, Janjanam J, Guo L, Virmani R, Rao GN. Myristoylation of LMCD1 leads to its species‐specific derepression of E2F1 and NFATc1 in the modulation of CDC6 and IL‐33 expression during development of vascular lesions. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.04754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
19
|
Raghavan S, Singh NK, Gali S, Mani AM, Rao GN. Protein Kinase Cθ Via Activating Transcription Factor 2-Mediated CD36 Expression and Foam Cell Formation of Ly6C hi Cells Contributes to Atherosclerosis. Circulation 2019; 138:2395-2412. [PMID: 29991487 DOI: 10.1161/circulationaha.118.034083] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Although the role of thrombin in atherothrombosis is well studied, its role in the pathogenesis of diet-induced atherosclerosis is not known. METHODS Using a mouse model of diet-induced atherosclerosis and molecular biological approaches, here we have explored the role of thrombin and its G protein-coupled receptor signaling in diet-induced atherosclerosis. RESULTS In exploring the role of G protein-coupled receptor signaling in atherogenesis, we found that thrombin triggers foam cell formation via inducing CD36 expression, and these events require Par1-mediated Gα12-Pyk2-Gab1-protein kinase C (PKC)θ-dependent ATF2 activation. Genetic deletion of PKCθ in apolipoprotein E (ApoE)-/- mice reduced Western diet-induced plaque formation. Furthermore, thrombin induced Pyk2, Gab1, PKCθ, and ATF2 phosphorylation, CD36 expression, and foam cell formation in peritoneal macrophages of ApoE-/- mice. In contrast, thrombin only stimulated Pyk2 and Gab1 but not ATF2 phosphorylation or its target gene CD36 expression in the peritoneal macrophages of ApoE-/-:PKCθ-/- mice, and it had no effect on foam cell formation. In addition, the aortic root cross-sections of Western diet-fed ApoE-/- mice showed increased Pyk2, Gab1, PKCθ, and ATF2 phosphorylation and CD36 expression as compared with ApoE-/-:PKCθ-/- mice. Furthermore, although the monocytes from peripheral blood and the aorta of Western diet-fed ApoE-/- mice were found to contain more of Ly6Chi cells than Ly6Clo cells, the monocytes from Western diet-fed ApoE-/-:PKCθ-/- mice were found to contain more Ly6Clo cells than Ly6Chi cells. It is interesting to note that the Ly6Chi cells showed higher CD36 expression with enhanced capacity to form foam cells as compared with Ly6Clo cells. CONCLUSIONS These findings reveal for the first time that thrombin-mediated Par1-Gα12 signaling via targeting Pyk2-Gab1-PKCθ-ATF2-dependent CD36 expression might be playing a crucial role in diet-induced atherogenesis.
Collapse
Affiliation(s)
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Sivaiah Gali
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| |
Collapse
|
20
|
Govatati S, Pichavaram P, Janjanam J, Zhang B, Singh NK, Mani AM, Traylor JG, Orr AW, Rao GN. NFATc1-E2F1-LMCD1-Mediated IL-33 Expression by Thrombin Is Required for Injury-Induced Neointima Formation. Arterioscler Thromb Vasc Biol 2019; 39:1212-1226. [PMID: 31043075 PMCID: PMC6540998 DOI: 10.1161/atvbaha.119.312729] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Objective- IL (interleukin)-33 has been shown to play a role in endothelial dysfunction, but its role in atherosclerosis is controversial. Therefore, the purpose of this study is to examine its role in vascular wall remodeling following injury. Approach and Results- Thrombin induced IL-33 expression in a time-dependent manner in human aortic smooth muscle cells and inhibition of its activity by its neutralizing antibody suppressed thrombin induced human aortic smooth muscle cell migration but not DNA synthesis. In exploring the mechanisms, we found that Par1 (protease-activated receptor 1), Gαq/11 (Gα protein q/11), PLCβ3 (phospholipase Cβ3), NFATc1 (nuclear factor of activated T cells), E2F1 (E2F transcription factor 1), and LMCD1 (LIM and cysteine-rich domains protein 1) are involved in thrombin-induced IL-33 expression and migration. Furthermore, we identified an NFAT-binding site at -100 nt that mediates thrombin-induced IL-33 promoter activity. Interestingly, we observed that NFATc1, E2F1, and LMCD1 bind to NFAT site in response to thrombin and found that LMCD1, while alone has no significant effect, enhanced either NFATc1 or E2F1-dependent IL-33 promoter activity. In addition, we found that guidewire injury induces IL-33 expression in SMC and its neutralizing antibodies substantially reduce SMC migration and neointimal growth in vivo. Increased expression of IL-33 was also observed in human atherosclerotic lesions as compared to arteries without any lesions. Conclusions- The above findings reveal for the first time that thrombin-induced human aortic smooth muscle cell migration and injury-induced neointimal growth require IL-33 expression. In addition, thrombin-induced IL-33 expression requires LMCD1 enhanced combinatorial activation of NFATc1 and E2F1.
Collapse
MESH Headings
- Animals
- Binding Sites
- Cell Movement/drug effects
- Cell Proliferation/drug effects
- Co-Repressor Proteins/genetics
- Co-Repressor Proteins/metabolism
- Disease Models, Animal
- E2F1 Transcription Factor/genetics
- E2F1 Transcription Factor/metabolism
- Female
- Femoral Artery/drug effects
- Femoral Artery/injuries
- Femoral Artery/metabolism
- Femoral Artery/pathology
- HEK293 Cells
- Humans
- Interleukin-33/genetics
- Interleukin-33/metabolism
- LIM Domain Proteins/genetics
- LIM Domain Proteins/metabolism
- Male
- Mice, Inbred C57BL
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- NFATC Transcription Factors/genetics
- NFATC Transcription Factors/metabolism
- Neointima
- Promoter Regions, Genetic
- Signal Transduction
- Up-Regulation
- Vascular System Injuries/genetics
- Vascular System Injuries/metabolism
- Vascular System Injuries/pathology
Collapse
Affiliation(s)
- Suresh Govatati
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jagadeesh Janjanam
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Baolin Zhang
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nikhlesh K. Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Arul M. Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - James G. Traylor
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, LA 71103, USA
| | - A. Wayne Orr
- Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, LA 71103, USA
| | - Gadiparthi N. Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
21
|
Raghavan S, Singh NK, Gali S, Mani AM, Rao GN. Response by Raghavan et al to Letter Regarding Article, "Protein Kinase Cθ via Activating Transcription Factor 2-Mediated CD36 Expression and Foam Cell Formation of Ly6C hi Cells Contributes to Atherosclerosis". Circulation 2019; 139:2079-2080. [PMID: 31070938 DOI: 10.1161/circulationaha.119.039918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Sivaiah Gali
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis
| | | |
Collapse
|
22
|
Pichavaram P, Mani AM, Singh NK, Rao GN. Cholesterol crystals promote endothelial cell and monocyte interactions via H 2O 2-mediated PP2A inhibition, NFκB activation and ICAM1 and VCAM1 expression. Redox Biol 2019; 24:101180. [PMID: 31022672 PMCID: PMC6477634 DOI: 10.1016/j.redox.2019.101180] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 03/26/2019] [Indexed: 12/21/2022] Open
Abstract
In the present study, we show that cholesterol crystals induce NFκB activation, and ICAM1 and VCAM1 expression via xanthine oxidase-mediated H2O2 production and PP2A inhibition in influencing endothelial cell and monocyte interactions and all these adverse effects of cholesterol crystals could be attenuated by proresolving lipid mediator RvD1. In addition, feeding mice with cholesterol rich diet (CRD) increased xanthine oxidase expression, its activity and H2O2 production leading to PP2A inhibition, NFκB activation, and ICAM1 and VCAM1 expression and RvD1 attenuated all these effects of CRD substantially. Furthermore, peripheral blood mononuclear cells (PBMCs) from wild type mice when injected into mice that were fed with CRD or RvD1 + CRD showed increased leukocyte trafficking to arteries of CRD-fed mice as compared to RvD1 + CRD mice. These findings suggest that cholesterol crystals via promoting oxidant stress and inhibiting Ser/Thr phosphatases such as PP2A stimulate NFκB activation and ICAM1 and VCAM1 expression, and thereby enhance EC-monocyte interactions. In addition, proresolving lipid mediators such as RvD1 appear to exert their anti-inflammatory effects via countering the adverse effects of cholesterol crystals or CRD.
Collapse
Affiliation(s)
- Prahalathan Pichavaram
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| |
Collapse
|
23
|
Mani AM, Singh NK, Rao GN. Cholesterol crystals increase vascular permeability by inactivating SHP2 and disrupting adherens junctions. FASEB J 2019. [DOI: 10.1096/fasebj.2019.33.1_supplement.709.5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
24
|
Chattopadhyay R, Tinnikov A, Dyukova E, Singh NK, Kotla S, Mobley JA, Rao GN. Withdrawal: 12/15-Lipoxygenase-dependent ROS production is required for diet-induced endothelial barrier dysfunction. J Lipid Res 2019; 60:909. [PMID: 30936322 DOI: 10.1194/jlr.m055566err] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
25
|
Chattopadhyay R, Dyukova E, Singh NK, Ohba M, Mobley JA, Rao GN. Correction: Vascular endothelial tight junctions and barrier function are disrupted by 15( S)-hydroxyeicosatetraenoic acid partly via protein kinase C ϵ-mediated zona occludens-1 phosphorylation at threonine 770/772. J Biol Chem 2019; 294:3311. [PMID: 30824571 DOI: 10.1074/jbc.aac119.007869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
|
26
|
Abstract
12/15-lipoxygenase (12/15-LOX) is an enzyme, which oxidizes polyunsaturated fatty acids, particularly omega-6 and -3 fatty acids, to generate a number of bioactive lipid metabolites. A large number of studies have revealed the importance of 12/15-LOX role in oxidative and inflammatory responses. The in vitro studies have demonstrated the ability of 12/15-LOX metabolites in the expression of various genes and production of cytokine related to inflammation and resolution of inflammation. The studies with the use of knockout and transgenic animals for 12/15-LOX have further shown its involvement in the pathogenesis of a variety of human diseases, including cardiovascular, renal, neurological and metabolic disorders. This review summarizes our current knowledge on the role of 12/15-LOX in inflammation and various human diseases.
Collapse
Affiliation(s)
- Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street Memphis, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street Memphis, Memphis, TN 38163, USA.
| |
Collapse
|
27
|
Mani AM, Chattopadhyay R, Singh NK, Rao GN. Cholesterol crystals increase vascular permeability by inactivating SHP2 and disrupting adherens junctions. Free Radic Biol Med 2018; 123:72-84. [PMID: 29782988 PMCID: PMC6333100 DOI: 10.1016/j.freeradbiomed.2018.05.068] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 05/16/2018] [Accepted: 05/17/2018] [Indexed: 12/27/2022]
Abstract
To understand the adverse effects of cholesterol crystals on vascular homeostasis, we have studied their effects on endothelial barrier function. Cholesterol crystals increased endothelial barrier permeability in a dose and time dependent manner. In addition, cholesterol crystals induced tyrosine phosphorylation of VE-cadherin and α-catenin, disrupting endothelial AJ and its barrier function and these effects required xanthine oxidase-mediated H2O2 production, SHP2 inactivation and Frk activation. Similarly, feeding C57BL/6 mice with cholesterol-rich diet increased xanthine oxidase expression, H2O2 production, SHP2 inactivation and Frk activation leading to enhanced tyrosine phosphorylation of VE-cadherin and α-catenin, thereby disrupting endothelial AJ and increasing vascular permeability. Resolvin D1, a specialized proresolving mediator, prevented all these adverse effects of cholesterol crystals and cholesterol-rich diet in endothelial cells and mice, respectively. Based on these observations, it is likely that cholesterol crystals via disrupting AJ increase vascular permeability, a critical event of endothelial dysfunction and specialized proresolving mediators such as Resolvin D1 exert protection against these effects.
Collapse
Affiliation(s)
- Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Rima Chattopadhyay
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA.
| |
Collapse
|
28
|
Raghavan S, Singh NK, Mani AM, Rao GN. Protease-activated receptor 1 inhibits cholesterol efflux and promotes atherogenesis via cullin 3-mediated degradation of the ABCA1 transporter. J Biol Chem 2018; 293:10574-10589. [PMID: 29777060 DOI: 10.1074/jbc.ra118.003491] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 05/10/2018] [Indexed: 12/25/2022] Open
Abstract
Although signaling of thrombin via its receptor protease-activated receptor 1 (Par1) is known to occur in atherothrombosis, its link to the actual pathogenesis of this condition is less clear. To better understand the role of thrombin-Par1 signaling in atherosclerosis, here we have studied their effects on cellular cholesterol efflux in mice. We found that by activating Par1 and cullin 3-mediated ubiquitination and degradation of ABC subfamily A member 1 (ABCA1), thrombin inhibits cholesterol efflux in both murine macrophages and smooth muscle cells. Moreover, disruption of the Par1 gene rescued ABCA1 from Western diet-induced ubiquitination and degradation and restored cholesterol efflux in apolipoprotein E-deficient (ApoE-/-) mice. Similarly, the Par1 deletion diminished diet-induced atherosclerotic lesions in the ApoE-/- mice. These observations for the first time indicate a role for thrombin-Par1 signaling in the pathogenesis of diet-induced atherosclerosis. We identify cullin 3 as a cullin-RING ubiquitin E3 ligase that mediates ABCA1 ubiquitination and degradation and thereby inhibits cholesterol efflux. Furthermore, compared with peripheral blood mononuclear cells (PBMCs) from ApoE-/- mice, the PBMCs from ApoE-/-:Par1-/- mice exhibited decreased trafficking to inflamed arteries of Western diet-fed ApoE-/- mice. This finding suggested that besides inhibiting cholesterol efflux, thrombin-Par1 signaling also plays a role in the recruitment of leukocytes during diet-induced atherogenesis. Based on these findings, we conclude that thrombin-Par1 signaling appears to contribute to the pathogenesis of atherosclerosis by impairing cholesterol efflux from cells and by recruiting leukocytes to arteries.
Collapse
Affiliation(s)
- Somasundaram Raghavan
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Nikhlesh K Singh
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Arul M Mani
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Gadiparthi N Rao
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| |
Collapse
|
29
|
Singh N, Chattopadhyay RN, Mani AM, Rao GN. Resolvin D1 blocks ROS‐mediated inhibitory crosstalk between SHP2 and PP2A and suppresses endothelial‐monocyte interactions. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.574.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
30
|
Singh NK, Janjanam J, Zhang B, Mani AM, Traylor JG, Orr AW, Rao GN. LMCD1 acts as a coactivator for E2F1 in CDC6 expression to promote human aortic smooth muscle cell replication and atherogenesis. FASEB J 2018. [DOI: 10.1096/fasebj.2018.32.1_supplement.864.12] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | | | | | | | | | - A. Wayne Orr
- Louisiana State University Health Sciences CenterShreveportLA
| | | |
Collapse
|
31
|
Chattopadhyay R, Mani AM, Singh NK, Rao GN. Resolvin D1 blocks H 2O 2-mediated inhibitory crosstalk between SHP2 and PP2A and suppresses endothelial-monocyte interactions. Free Radic Biol Med 2018; 117:119-131. [PMID: 29408202 PMCID: PMC5845835 DOI: 10.1016/j.freeradbiomed.2018.01.034] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 01/30/2018] [Accepted: 01/31/2018] [Indexed: 12/30/2022]
Abstract
In recent years, various studies have demonstrated a role for endogenously derived specialized proresolving mediators such as resolvins in the resolution of inflammation. In exploring the signaling mechanisms, in the present study we show that Resolvin D1 (RvD1) reduces LPS-induced endothelial cell (EC)-monocyte interactions via blocking H2O2-mediated PP2A inactivation, NFκB activation and ICAM1 and VCAM1 expression. In addition, we found that H2O2-mediated SHP2 inhibition leads to tyrosine phosphorylation and inactivation of PP2A by LPS, which in turn, accounts for increased NFκB activation and ICAM1 and VCAM1 expression facilitating EC-monocyte interactions and all these LPS-mediated responses were reduced by RvD1. Furthermore, the suppression of NFκB activation, ICAM1 and VCAM1 expression and EC and monocyte interactions by RvD1 involved its receptors ALX/FPR2 and GPR32 as inhibition or neutralization of these receptors negated its effects. Besides, pertussis toxin completely prevented the effects of RvD1 on inhibition of LPS-induced H2O2 production, SHP2 and PP2A inactivation, NFκB activation, ICAM1 and VCAM1 expression and EC and monocyte interactions. Together, these observations suggest that RvD1 via activation of Gi-coupled ALX/FPR2 and GPR32 receptors blocks LPS-induced H2O2-mediated SHP2 and PP2A inactivation, NFκB activation, ICAM1 and VCAM1 expression and EC-monocyte interactions, which could be one of the several possible mechanisms underlying the anti-inflammatory actions of this specialized proresolving mediator.
Collapse
Affiliation(s)
- Rima Chattopadhyay
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Arul M Mani
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 71 S. Manassas Street, Memphis, TN 38163, USA.
| |
Collapse
|
32
|
Janjanam J, Zhang B, Mani AM, Singh NK, Traylor JG, Orr AW, Rao GN. LIM and cysteine-rich domains 1 is required for thrombin-induced smooth muscle cell proliferation and promotes atherogenesis. J Biol Chem 2018; 293:3088-3103. [PMID: 29326163 DOI: 10.1074/jbc.ra117.000866] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 01/09/2018] [Indexed: 11/06/2022] Open
Abstract
Restenosis arises after vascular injury and is characterized by arterial wall thickening and decreased arterial lumen space. Vascular injury induces the production of thrombin, which in addition to its role in blood clotting acts as a mitogenic and chemotactic factor. In exploring the molecular mechanisms underlying restenosis, here we identified LMCD1 (LIM and cysteine-rich domains 1) as a gene highly responsive to thrombin in human aortic smooth muscle cells (HASMCs). Of note, LMCD1 depletion inhibited proliferation of human but not murine vascular smooth muscle cells. We also found that by physically interacting with E2F transcription factor 1, LMCD1 mediates thrombin-induced expression of the CDC6 (cell division cycle 6) gene in the stimulation of HASMC proliferation. Thrombin-induced LMCD1 and CDC6 expression exhibited a requirement for protease-activated receptor 1-mediated Gαq/11-dependent activation of phospholipase C β3. Moreover, the expression of LMCD1 was highly induced in smooth muscle cells located at human atherosclerotic lesions and correlated with CDC6 expression and that of the proliferation marker Ki67. Furthermore, the LMCD1- and SMCαactin-positive cells had higher cholesterol levels in the atherosclerotic lesions. In conclusion, these findings indicate that by acting as a co-activator with E2F transcription factor 1 in CDC6 expression, LMCD1 stimulates HASMC proliferation and thereby promotes human atherogenesis, suggesting an involvement of LMCD1 in restenosis.
Collapse
Affiliation(s)
- Jagadeesh Janjanam
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Baolin Zhang
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Arul M Mani
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Nikhlesh K Singh
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - James G Traylor
- the Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71103
| | - A Wayne Orr
- the Department of Pathology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71103
| | - Gadiparthi N Rao
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| |
Collapse
|
33
|
Kotla S, Singh NK, Kirchhofer D, Rao GN. Heterodimers of the transcriptional factors NFATc3 and FosB mediate tissue factor expression for 15( S)-hydroxyeicosatetraenoic acid-induced monocyte trafficking. J Biol Chem 2017; 292:14885-14901. [PMID: 28724635 PMCID: PMC5592668 DOI: 10.1074/jbc.m117.804344] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 07/14/2017] [Indexed: 12/26/2022] Open
Abstract
Tissue factor (TF) is expressed in vascular and nonvascular tissues and functions in several pathways, including embryonic development, inflammation, and cell migration. Many risk factors for atherosclerosis, including hypertension, diabetes, obesity, and smoking, increase TF expression. To better understand the TF-related mechanisms in atherosclerosis, here we investigated the role of 12/15-lipoxygenase (12/15-LOX) in TF expression. 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), the major product of human 15-LOXs 1 and 2, induced TF expression and activity in a time-dependent manner in the human monocytic cell line THP1. Moreover, TF suppression with neutralizing antibodies blocked 15(S)-HETE-induced monocyte migration. We also found that NADPH- and xanthine oxidase-dependent reactive oxygen species (ROS) production, calcium/calmodulin-dependent protein kinase IV (CaMKIV) activation, and interactions between nuclear factor of activated T cells 3 (NFATc3) and FosB proto-oncogene, AP-1 transcription factor subunit (FosB) are involved in 15(S)-HETE-induced TF expression. Interestingly, NFATc3 first induced the expression of its interaction partner FosB before forming the heterodimeric NFATc3-FosB transcription factor complex, which bound the proximal AP-1 site in the TF gene promoter and activated TF expression. We also observed that macrophages from 12/15-LOX-/- mice exhibit diminished migratory response to monocyte chemotactic protein 1 (MCP-1) and lipopolysaccharide compared with WT mouse macrophages. Similarly, compared with WT macrophages, monocytes from 12/15-LOX-/- mice displayed diminished trafficking, which was rescued by prior treatment with 12(S)-HETE, in a peritonitis model. These observations indicate that 15(S)-HETE-induced monocyte/macrophage migration and trafficking require ROS-mediated CaMKIV activation leading to formation of NFATc3 and FosB heterodimer, which binds and activates the TF promoter.
Collapse
Affiliation(s)
- Sivareddy Kotla
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Nikhlesh K Singh
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| | - Daniel Kirchhofer
- Department of Early Discovery Biochemistry, Genentech Inc., South San Francisco, California 94080
| | - Gadiparthi N Rao
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163 and
| |
Collapse
|
34
|
Singh NK, Janjanam J, Rao GN. p115 RhoGEF activates the Rac1 GTPase signaling cascade in MCP1 chemokine-induced vascular smooth muscle cell migration and proliferation. J Biol Chem 2017; 292:14080-14091. [PMID: 28655771 DOI: 10.1074/jbc.m117.777896] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 06/20/2017] [Indexed: 12/30/2022] Open
Abstract
Although the involvement of Rho proteins in the pathogenesis of vascular diseases is well studied, little is known about the role of their upstream regulators, the Rho guanine nucleotide exchange factors (RhoGEFs). Here, we sought to identify the RhoGEFs involved in monocyte chemotactic protein 1 (MCP1)-induced vascular wall remodeling. We found that, among the RhoGEFs tested, MCP1 induced tyrosine phosphorylation of p115 RhoGEF but not of PDZ RhoGEF or leukemia-associated RhoGEF in human aortic smooth muscle cells (HASMCs). Moreover, p115 RhoGEF inhibition suppressed MCP1-induced HASMC migration and proliferation. Consistent with these observations, balloon injury (BI) induced p115 RhoGEF tyrosine phosphorylation in rat common carotid arteries, and siRNA-mediated down-regulation of its levels substantially attenuated BI-induced smooth muscle cell migration and proliferation, resulting in reduced neointima formation. Furthermore, depletion of p115 RhoGEF levels also abrogated MCP1- or BI-induced Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling, which, as we reported previously, is involved in vascular wall remodeling. Our findings also show that protein kinase N1 (PKN1) downstream of Rac1-cyclin D1/CDK6 and upstream of CDK4-PAK1 in the p115 RhoGEF-Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling axis is involved in the modulation of vascular wall remodeling. Of note, we also observed that CCR2-Gi/o-Fyn signaling mediates MCP1-induced p115 RhoGEF and Rac1 GTPase activation. These findings suggest that p115 RhoGEF is critical for MCP1-induced HASMC migration and proliferation in vitro and for injury-induced neointima formation in vivo by modulating Rac1-NFATc1-cyclin D1-CDK6-PKN1-CDK4-PAK1 signaling.
Collapse
Affiliation(s)
- Nikhlesh K Singh
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163.
| | - Jagadeesh Janjanam
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Gadiparthi N Rao
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163.
| |
Collapse
|
35
|
Chattopadhyay R, Raghavan S, Rao GN. Resolvin D1 via prevention of ROS-mediated SHP2 inactivation protects endothelial adherens junction integrity and barrier function. Redox Biol 2017; 12:438-455. [PMID: 28319894 PMCID: PMC5357675 DOI: 10.1016/j.redox.2017.02.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 02/27/2017] [Indexed: 01/30/2023] Open
Abstract
Resolvins are a novel class of lipid mediators that play an important role in the resolution of inflammation, although the underlying mechanisms are not very clear. To explore the anti-inflammatory mechanisms of resolvins, we have studied the effects of resolvin D1 (RvD1) on lipopolysaccharide (LPS)-induced endothelial barrier disruption as it is linked to propagation of inflammation. We found that LPS induces endothelial cell (EC) barrier disruption via xanthine oxidase (XO)-mediated reactive oxygen species (ROS) production, protein tyrosine phosphatase SHP2 inactivation and Fyn-related kinase (Frk) activation leading to tyrosine phosphorylation of α-catenin and VE-cadherin and their dissociation from each other affecting adherens junction (AJ) integrity and thereby increasing endothelial barrier permeability. RvD1 attenuated LPS-induced AJ disassembly and endothelial barrier permeability by arresting tyrosine phosphorylation of α-catenin and VE-cadherin and their dislocation from AJ via blockade of XO-mediated ROS production and thereby suppression of SHP2 inhibition and Frk activation. We have also found that the protective effects of RvD1 on EC barrier function involve ALX/FPR2 and GPR32 as inhibition or neutralization of these receptors negates its protective effects. LPS also increased XO activity, SHP2 cysteine oxidation and its inactivation, Frk activation, α-catenin and VE-cadherin tyrosine phosphorylation and their dissociation from each other leading to AJ disruption with increased vascular permeability in mice arteries and RvD1 blocked all these effects. Thus, RvD1 protects endothelial AJ and its barrier function from disruption by inflammatory mediators such as LPS via a mechanism involving the suppression of XO-mediated ROS production and blocking SHP2 inactivation.
Collapse
Affiliation(s)
- Rima Chattopadhyay
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Somasundaram Raghavan
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| |
Collapse
|
36
|
Kotla S, Singh NK, Rao GN. ROS via BTK-p300-STAT1-PPARγ signaling activation mediates cholesterol crystals-induced CD36 expression and foam cell formation. Redox Biol 2016; 11:350-364. [PMID: 28040583 PMCID: PMC5200884 DOI: 10.1016/j.redox.2016.12.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 11/28/2016] [Accepted: 12/02/2016] [Indexed: 12/12/2022] Open
Abstract
In understanding the mechanisms of cholesterol in the pathogenesis of atherosclerosis, previous studies from other laboratories have demonstrated that cholesterol crystals (CC) induce scavenger receptor CD36 expression and NLRP3-mediated inflammasome formation. In elucidating the mechanisms by which CC could enhance CD36 expression and foam cell formation, here we report that CC via NADPH and xanthine oxidases-mediated ROS production activates BTK, a non-receptor tyrosine kinase. In addition, CC induce p300 tyrosine phosphorylation and activation in a BTK-dependent manner, which in turn, leads to STAT1 acetylation and its interaction with PPARγ in CD36 expression, oxLDL uptake and foam cell formation. Furthermore, p300, STAT1 and PPARγ bound to a STAT binding site at −107 nt in CD36 promoter and enhanced its activity in ROS and BTK-dependent manner. Disruption of this STAT binding site by site-directed mutagenesis abolished CC-induced CD36 promoter activity. Together these results reveal for the first time that CC via producing ROS and activating BTK causes p300-mediated STAT1 acetylation and its interaction with PPARγ in CD36 expression, oxLDL uptake and foam cell formation. CC induces CD36 expression and foam cell formation by ROS-mediated BTK activation. STAT1 and PPARγ interactions are required for CC-induced CD36 expression. ROS-dependent BTK and p300 activation mediate STAT1 and PPARγ interactions.
Collapse
Affiliation(s)
- Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA.
| |
Collapse
|
37
|
Kumar R, Janjanam J, Singh NK, Rao GN. Abstract 368: Novel Role of Cofilin in Retinal Neovascularization. Arterioscler Thromb Vasc Biol 2016. [DOI: 10.1161/atvb.36.suppl_1.368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Pak1 plays an important role in several cellular processes including cell migration, but its role in pathological angiogenesis is not known. Here we have determined its role in pathological retinal angiogenesis using Oxygen Induced Retinopathy (OIR) model. VEGFA induced Pak1 and its effector cofilin phosphorylation in time-dependent as well as p38β-dependent manner in HRMVECs. Depletion of the levels of any of these molecules inhibited VEGFA-induced HRMVECs F-actin stress fiber formation, migration, proliferation, sprouting, and tube formation. In accordance with these observations, hypoxia induced Pak1 and Cofilin phosphorylation with p38β being downstream to Pak1 and upstream to cofilin. Furthermore, Pak1 deficiency abolished hypoxia-induced p38β and cofilin phosphorylation and abrogated retinal endothelial cell proliferation, tip cell formation and neovascularization. In addition, siRNA-mediated downregulation of p38β or cofilin levels in WT mouse retina also diminished endothelial cell proliferation, tip cell formation and neovascularization. Together, these observations suggest that, while p38β-Pak1-cofilin axis is required for HRMVECs migration, proliferation, sprouting and tubulogenesis, Pak1-p38β-cofilin signaling is essential for hypoxia-induced retinal endothelial cell proliferation, tip cell formation and neovascularization.
Collapse
Affiliation(s)
- Raj Kumar
- Physiology, Univ of Tennessee Health Science Cntr, Memphis, TN
| | | | | | | |
Collapse
|
38
|
Kumar R, Janjanam J, Singh NK, Rao GN. A new role for cofilin in retinal neovascularization. J Cell Sci 2016; 129:1234-49. [PMID: 26857814 DOI: 10.1242/jcs.179382] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Accepted: 02/02/2016] [Indexed: 12/17/2022] Open
Abstract
Pak1 plays an important role in several cellular processes, including cell migration, but its role in pathological angiogenesis is not known. Here, we have determined its role in pathological retinal angiogenesis using an oxygen-induced retinopathy (OIR) model. VEGFA induced phosphorylation of Pak1 and its effector cofilin in a manner that was dependent on time as well as p38MAPKβ (also known as MAPK11) in human retinal microvascular endothelial cells (HRMVECs). Depletion of the levels of any of these molecules inhibited VEGFA-induced HRMVEC F-actin stress fiber formation, migration, proliferation, sprouting and tube formation. In accordance with these observations, hypoxia induced Pak1 and cofilin phosphorylation with p38MAPKβ being downstream to Pak1 and upstream to cofilin in mouse retina. Furthermore, Pak1 deficiency abolished hypoxia-induced p38MAPKβ and cofilin phosphorylation and abrogated retinal endothelial cell proliferation, tip cell formation and neovascularization. In addition, small interfering RNA (siRNA)-mediated downregulation of p38MAPKβ or cofilin levels in the wild-type mouse retina also diminished endothelial cell proliferation, tip cell formation and neovascularization. Taken together, these observations suggest that, although the p38MAPKβ-Pak1-cofilin axis is required for HRMVEC migration, proliferation, sprouting and tubulogenesis, Pak1-p38MAPKβ-cofilin signaling is also essential for hypoxia-induced mouse retinal endothelial cell proliferation, tip cell formation and neovascularization.
Collapse
Affiliation(s)
- Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Jagadeesh Janjanam
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
39
|
Kotla S, Rao GN. Reactive Oxygen Species (ROS) Mediate p300-dependent STAT1 Protein Interaction with Peroxisome Proliferator-activated Receptor (PPAR)-γ in CD36 Protein Expression and Foam Cell Formation. J Biol Chem 2015; 290:30306-20. [PMID: 26504087 DOI: 10.1074/jbc.m115.686865] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Indexed: 01/24/2023] Open
Abstract
Previously, we have demonstrated that 15(S)-hydroxyeicosatetranoic acid (15(S)-HETE) induces CD36 expression involving STAT1. Many studies have shown that peroxisome proliferator-activated receptor (PPAR)-γ mediates CD36 expression. Therefore, we asked the question whether these transcriptional factors interact with each other in the regulation of CD36 expression by 15(S)-HETE. Here, we show that STAT1 interacts with PPARγ in the induction of CD36 expression and foam cell formation by 15(S)-HETE. In addition, using molecular biological approaches such as EMSA, supershift EMSA, ChIP, re-ChIP, and promoter-reporter gene assays, we demonstrate that the STAT1 and PPARγ complex binds to the STAT-binding site at -107 nucleotides in the CD36 promoter and enhances its activity. Furthermore, the interaction of STAT1 with PPARγ depends on STAT1 acetylation, which is mediated by p300. In addition, our findings show that reactive oxygen species-dependent Syk and Pyk2 stimulation is required for p300 tyrosine phosphorylation and activation. Together, these results demonstrate that an interaction between STAT1, p300, and peroxisome proliferator-activated receptor-γ is required for 15(S)-HETE-induced CD36 expression, oxidized low density lipoprotein uptake, and foam cell formation, critical events underlying the pathogenesis of atherosclerosis.
Collapse
Affiliation(s)
- Sivareddy Kotla
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | - Gadiparthi N Rao
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| |
Collapse
|
40
|
Janjanam J, Chandaka GK, Kotla S, Rao GN. PLCβ3 mediates cortactin interaction with WAVE2 in MCP1-induced actin polymerization and cell migration. Mol Biol Cell 2015; 26:4589-606. [PMID: 26490115 PMCID: PMC4678017 DOI: 10.1091/mbc.e15-08-0570] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 10/13/2015] [Indexed: 12/24/2022] Open
Abstract
Monocyte chemotactic protein 1 (MCP1) stimulates vascular smooth muscle cell (VSMC) migration in vascular wall remodeling. However, the mechanisms underlying MCP1-induced VSMC migration have not been understood. Here we identify the signaling pathway associated with MCP1-induced human aortic smooth muscle cell (HASMC) migration. MCP1, a G protein-coupled receptor agonist, activates phosphorylation of cortactin on S405 and S418 residues in a time-dependent manner, and inhibition of its phosphorylation attenuates MCP1-induced HASMC G-actin polymerization, F-actin stress fiber formation, and migration. Cortactin phosphorylation on S405/S418 is found to be critical for its interaction with WAVE2, a member of the WASP family of cytoskeletal regulatory proteins required for cell migration. In addition, the MCP1-induced cortactin phosphorylation is dependent on PLCβ3-mediated PKCδ activation, and siRNA-mediated down-regulation of either of these molecules prevents cortactin interaction with WAVE2, affecting G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Upstream, MCP1 activates CCR2 and Gαq/11 in a time-dependent manner, and down-regulation of their levels attenuates MCP1-induced PLCβ3 and PKCδ activation, cortactin phosphorylation, cortactin-WAVE2 interaction, G-actin polymerization, F-actin stress fiber formation, and HASMC migration. Together these findings demonstrate that phosphorylation of cortactin on S405 and S418 residues is required for its interaction with WAVE2 in MCP1-induced cytoskeleton remodeling, facilitating HASMC migration.
Collapse
Affiliation(s)
- Jagadeesh Janjanam
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Giri Kumar Chandaka
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163
| |
Collapse
|
41
|
Singh NK, Kotla S, Kumar R, Rao GN. Cyclic AMP Response Element Binding Protein Mediates Pathological Retinal Neovascularization via Modulating DLL4-NOTCH1 Signaling. EBioMedicine 2015; 2:1767-84. [PMID: 26870802 PMCID: PMC4740322 DOI: 10.1016/j.ebiom.2015.09.042] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 09/08/2015] [Accepted: 09/23/2015] [Indexed: 11/29/2022] Open
Abstract
Retinal neovascularization is the most common cause of moderate to severe vision loss in all age groups. Despite the use of anti-VEGFA therapies, this complication continues to cause blindness, suggesting a role for additional molecules in retinal neovascularization. Besides VEGFA and VEGFB, hypoxia induced VEGFC expression robustly. Based on this finding, we tested the role of VEGFC in pathological retinal angiogenesis. VEGFC induced proliferation, migration, sprouting and tube formation of human retinal microvascular endothelial cells (HRMVECs) and these responses require CREB-mediated DLL4 expression and NOTCH1 activation. Furthermore, down regulation of VEGFC levels substantially reduced tip cell formation and retinal neovascularization in vivo. In addition, we observed that CREB via modulating the DLL4-NOTCH1 signaling mediates VEGFC-induced tip cell formation and retinal neovascularization. In regard to upstream mechanism, we found that down regulation of p38β levels inhibited hypoxia-induced CREB-DLL4-NOTCH1 activation, tip cell formation, sprouting and retinal neovascularization. Based on these findings, it may be suggested that VEGFC besides its role in the regulation of lymphangiogenesis also plays a role in pathological retinal angiogenesis and this effect depends on p38β and CREB-mediated activation of DLL4-NOTCH1 signaling.
Collapse
Affiliation(s)
- Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Raj Kumar
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163, USA
| |
Collapse
|
42
|
Singh NK, Kotla S, Dyukova E, Traylor JG, Orr AW, Chernoff J, Marion TN, Rao GN. Disruption of p21-activated kinase 1 gene diminishes atherosclerosis in apolipoprotein E-deficient mice. Nat Commun 2015; 6:7450. [PMID: 26104863 PMCID: PMC4480433 DOI: 10.1038/ncomms8450] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 05/09/2015] [Indexed: 12/26/2022] Open
Abstract
Pak1 plays an important role in various cellular processes, including cell motility, polarity, survival and proliferation. To date, its role in atherogenesis has not been explored. Here we report the effect of Pak1 on atherogenesis using atherosclerosis-prone apolipoprotein E-deficient (ApoE−/−) mice as a model. Disruption of Pak1 in ApoE−/− mice results in reduced plaque burden, significantly attenuates circulating IL-6 and MCP-1 levels, limits the expression of adhesion molecules and diminishes the macrophage content in the aortic root of ApoE−/− mice. We also observed reduced oxidized LDL uptake and increased cholesterol efflux by macrophages and smooth muscle cells of ApoE−/−:Pak1−/− mice as compared with ApoE−/− mice. In addition, we detect increased Pak1 phosphorylation in human atherosclerotic arteries, suggesting its role in human atherogenesis. Altogether, these results identify Pak1 as an important factor in the initiation and progression of atherogenesis. Atherogenesis involves coordinated action of different cell types and factors. Here the authors show that the kinase Pak1 represents a key pro-atherogenic factor affecting the function of macrophages and vascular smooth muscle cells, including their production of proinflammatory cytokine IL-6 and chemokine MCP-1, and retention of cholesterol.
Collapse
Affiliation(s)
- Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, Tennessee 38163, USA
| | - Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, Tennessee 38163, USA
| | - Elena Dyukova
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, Tennessee 38163, USA
| | - James G Traylor
- Department of Pathology, LSU Health Sciences Center, Shreveport, Louisiana 71103, USA
| | - A Wayne Orr
- Department of Pathology, LSU Health Sciences Center, Shreveport, Louisiana 71103, USA
| | - Jonathan Chernoff
- Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, Pennsylvania 19111, USA
| | - Tony N Marion
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee 38163, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, Tennessee 38163, USA
| |
Collapse
|
43
|
Chattopadhyay R, Tinnikov A, Dyukova E, Singh NK, Kotla S, Mobley JA, Rao GN. 12/15-Lipoxygenase-dependent ROS production is required for diet-induced endothelial barrier dysfunction. J Lipid Res 2015; 56:562-577. [PMID: 25556764 DOI: 10.1194/jlr.m055566] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
To understand the mechanisms of 15(S)-HETE-induced endothelial cell (EC) barrier dysfunction, we examined the role of xanthine oxidase (XO). 15(S)-HETE induced junction adhesion molecule A (JamA) phosphorylation on Y164, Y218, and Y280 involving XO-mediated reactive oxygen species production and Src and Pyk2 activation, resulting in its dissociation from occludin, thereby causing tight junction (TJ) disruption, increased vascular permeability, and enhanced leukocyte and monocyte transmigration in vitro using EC monolayer and ex vivo using arteries as models. The phosphorylation of JamA on Y164, Y218, and Y280 appears to be critical for its role in 15(S)-HETE-induced EC barrier dysfunction, as mutation of any one of these amino acid residues prevented its dissociation from occludin and restored TJ integrity and barrier function. In response to high-fat diet (HFD) feeding, WT, but not 12/15-lipoxygenase (LO)(-/-), mice showed enhanced XO expression and its activity in the artery, which was correlated with increased aortic TJ disruption and barrier permeability with enhanced leukocyte adhesion and these responses were inhibited by allopurinol. These observations provide novel insights on the role of XO in 12/15-LO-induced JamA tyrosine phosphorylation and TJ disruption leading to increased vascular permeability in response to HFD.
Collapse
Affiliation(s)
- Rima Chattopadhyay
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138
| | - Alexander Tinnikov
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138
| | - Elena Dyukova
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138
| | - Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138
| | - James A Mobley
- Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35291
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38138.
| |
Collapse
|
44
|
Kotla S, Singh NK, Traylor JG, Orr AW, Rao GN. ROS-dependent Syk and Pyk2-mediated STAT1 activation is required for 15(S)-hydroxyeicosatetraenoic acid-induced CD36 expression and foam cell formation. Free Radic Biol Med 2014; 76:147-62. [PMID: 25152235 PMCID: PMC4253592 DOI: 10.1016/j.freeradbiomed.2014.08.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Revised: 08/07/2014] [Accepted: 08/11/2014] [Indexed: 02/02/2023]
Abstract
15(S)-Hydroxyeicosatetraenoic acid (15(S)-HETE), the major 15-lipoxygenase 1/2 (15-LO1/2) metabolite of arachidonic acid (AA), induces CD36 expression through xanthine oxidase and NADPH oxidase-dependent ROS production and Syk and Pyk2-dependent STAT1 activation. In line with these observations, 15(S)-HETE also induced foam cell formation involving ROS, Syk, Pyk2, and STAT1-mediated CD36 expression. In addition, peritoneal macrophages from Western diet-fed ApoE(-/-) mice exhibited elevated levels of xanthine oxidase and NADPH oxidase activities, ROS production, Syk, Pyk2, and STAT1 phosphorylation, and CD36 expression compared to those from ApoE(-/-):12/15-LO(-/-) mice and these events correlated with increased lipid deposits, macrophage content, and lesion progression in the aortic roots. Human atherosclerotic arteries also showed increased 15-LO1 expression, STAT1 phosphorylation, and CD36 levels as compared to normal arteries. Together, these findings suggest that 12/15-LO metabolites of AA, particularly 12/15(S)-HETE, might play a crucial role in atherogenesis by enhancing foam cell formation.
Collapse
Affiliation(s)
- Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA
| | - Nikhlesh K Singh
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA
| | - James G Traylor
- Department of Pathology, Louisiana State University Health Science Center, 1501 King׳s Hwy, Shreveport, LA 71130, USA
| | - A Wayne Orr
- Department of Pathology, Louisiana State University Health Science Center, 1501 King׳s Hwy, Shreveport, LA 71130, USA
| | - Gadiparthi N Rao
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA.
| |
Collapse
|
45
|
Kotla S, Singh NK, Rao GN. Abstract 674: 15(S)-Hydroxyeicosatetraenoic Acid Induces Foam Cell Formation by Enhancing CD36 Expression via Activation of ROS-Syk-Pyk2-STAT1 Signaling. Arterioscler Thromb Vasc Biol 2014. [DOI: 10.1161/atvb.34.suppl_1.674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
15(S)-Hydroxyeicosatetraenoic acid (15(S)-HETE), the major 15-lipoxygenase 1 (15-LO1) metabolite of arachidonic acid (AA), induces CD36 expression in xanthine oxidase and NADPH oxidase-dependent ROS production and Syk and Pyk2-dependent STAT1 activation. In line with these observations, 15(S)-HETE also induced foam cell formation involving ROS, Syk, Pyk2 and STAT1-mediated CD36 expression. In addition, peritoneal macrophages from high-fat diet-fed ApoE-/- mice exhibited elevated levels of xanthine oxidase and NADPH oxidase activities, ROS production, Syk, Pyk2, and STAT1 phosphorylation and CD36 expression compared to those from ApoE-/-:12/15-LO-/- mice and these events correlated well with increased lipid deposits and macrophage content in the aortic arches resulting in atherosclerotic plaque formation. These findings strongly suggest that 12/15-LO metabolites of AA such as 15(S)-HETE play a crucial role in atherogenesis by enhancing foam cell formation.
Collapse
|
46
|
Chattopadhyay R, Dyukova E, Singh NK, Ohba M, Mobley JA, Rao GN. Vascular endothelial tight junctions and barrier function are disrupted by 15(S)-hydroxyeicosatetraenoic acid partly via protein kinase C ε-mediated zona occludens-1 phosphorylation at threonine 770/772. J Biol Chem 2013; 289:3148-63. [PMID: 24338688 DOI: 10.1074/jbc.m113.528190] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Disruption of tight junctions (TJs) perturbs endothelial barrier function and promotes inflammation. Previously, we have shown that 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE), the major 15-lipoxygenase 1 (15-LO1) metabolite of arachidonic acid, by stimulating zona occludens (ZO)-2 tyrosine phosphorylation and its dissociation from claudins 1/5, induces endothelial TJ disruption and its barrier dysfunction. Here, we have studied the role of serine/threonine phosphorylation of TJ proteins in 15(S)-HETE-induced endothelial TJ disruption and its barrier dysfunction. We found that 15(S)-HETE enhances ZO-1 phosphorylation at Thr-770/772 residues via PKCε-mediated MEK1-ERK1/2 activation, causing ZO-1 dissociation from occludin, disrupting endothelial TJs and its barrier function, and promoting monocyte transmigration; these effects were reversed by T770A/T772A mutations. In the arteries of WT mice ex vivo, 15(S)-HETE also induced ZO-1 phosphorylation and endothelial TJ disruption in a PKCε and MEK1-ERK1/2-dependent manner. In line with these observations, in WT mice high fat diet feeding induced 12/15-lipoxygenase (12/15-LO) expression in the endothelium and caused disruption of its TJs and barrier function. However, in 12/15-LO(-/-) mice, high fat diet feeding did not cause disruption of endothelial TJs and barrier function. These observations suggest that the 12/15-LO-12/15(S)-HETE axis, in addition to tyrosine phosphorylation of ZO-2, also stimulates threonine phosphorylation of ZO-1 in the mediation of endothelial TJ disruption and its barrier dysfunction.
Collapse
Affiliation(s)
- Rima Chattopadhyay
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | | | | | | | | | | |
Collapse
|
47
|
Kotla S, Singh NK, Heckle MR, Tigyi GJ, Rao GN. The transcription factor CREB enhances interleukin-17A production and inflammation in a mouse model of atherosclerosis. Sci Signal 2013; 6:ra83. [PMID: 24045154 DOI: 10.1126/scisignal.2004214] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The enzyme 15-lipoxygenase (15-LO) plays a role in atherogenesis (also known as atherosclerosis), but the underlying mechanisms are unclear. We found that 15(S)-hydroxyeicosatetraenoic acid [15(S)-HETE], the major 15-LO-dependent metabolite of arachidonic acid, stimulated the production of reactive oxygen species (ROS) by monocytes through the xanthine oxidase-mediated activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. ROS production led to the Syk-, Pyk2-, and mitogen-activated protein kinase (MAPK)-dependent production of the proinflammatory cytokine interleukin-17A (IL-17A) in a manner that required the transcription factor CREB (cyclic adenosine monophosphate response element-binding protein). In addition, this pathway was required for the 15(S)-HETE-dependent migration and adhesion of monocytes to endothelial cells. Consistent with these observations, we found that peritoneal macrophages from apolipoprotein E-deficient (ApoE-/-) mice fed a high-fat diet (a mouse model of atherosclerosis) exhibited increased xanthine oxidase and NADPH oxidase activities; ROS production; phosphorylation of Syk, Pyk2, MAPK, and CREB; and IL-17A production compared to those from similarly fed ApoE-/-:12/15-LO-/- mice. These events correlated with increased lipid deposits and numbers of monocytes and macrophages in the aortic arches of ApoE-/- mice, which resulted in atherosclerotic plaque formation. Together, these observations suggest that 15(S)-HETE exacerbates atherogenesis by enhancing CREB-dependent IL-17A production and inflammation.
Collapse
Affiliation(s)
- Sivareddy Kotla
- Department of Physiology, University of Tennessee Health Science Center, 894 Union Avenue, Memphis, TN 38163, USA
| | | | | | | | | |
Collapse
|
48
|
Gadepalli R, Kotla S, Heckle MR, Verma SK, Singh NK, Rao GN. Novel role for p21-activated kinase 2 in thrombin-induced monocyte migration. J Biol Chem 2013; 288:30815-31. [PMID: 24025335 DOI: 10.1074/jbc.m113.463414] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
To understand the role of thrombin in inflammation, we tested its effects on migration of THP-1 cells, a human monocytic cell line. Thrombin induced THP-1 cell migration in a dose-dependent manner. Thrombin induced tyrosine phosphorylation of Pyk2, Gab1, and p115 RhoGEF, leading to Rac1- and RhoA-dependent Pak2 activation. Downstream to Pyk2, Gab1 formed a complex with p115 RhoGEF involving their pleckstrin homology domains. Furthermore, inhibition or depletion of Pyk2, Gab1, p115 RhoGEF, Rac1, RhoA, or Pak2 levels substantially attenuated thrombin-induced THP-1 cell F-actin cytoskeletal remodeling and migration. Inhibition or depletion of PAR1 also blocked thrombin-induced activation of Pyk2, Gab1, p115 RhoGEF, Rac1, RhoA, and Pak2, resulting in diminished THP-1 cell F-actin cytoskeletal remodeling and migration. Similarly, depletion of Gα12 negated thrombin-induced Pyk2, Gab1, p115 RhoGEF, Rac1, RhoA, and Pak2 activation, leading to attenuation of THP-1 cell F-actin cytoskeletal remodeling and migration. These novel observations reveal that thrombin induces monocyte/macrophage migration via PAR1-Gα12-dependent Pyk2-mediated Gab1 and p115 RhoGEF interactions, leading to Rac1- and RhoA-targeted Pak2 activation. Thus, these findings provide mechanistic evidence for the role of thrombin and its receptor PAR1 in inflammation.
Collapse
Affiliation(s)
- Ravisekhar Gadepalli
- From the Department of Physiology, University of Tennessee Health Science Center, Memphis, Tennessee 38163
| | | | | | | | | | | |
Collapse
|
49
|
Kundumani-Sridharan V, Singh NK, Kumar S, Gadepalli R, Rao GN. Nuclear factor of activated T cells c1 mediates p21-activated kinase 1 activation in the modulation of chemokine-induced human aortic smooth muscle cell F-actin stress fiber formation, migration, and proliferation and injury-induced vascular wall remodeling. J Biol Chem 2013; 288:22150-62. [PMID: 23737530 DOI: 10.1074/jbc.m113.454082] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recent literature suggests that cyclin-dependent kinases (CDKs) mediate cell migration. However, the mechanisms were not known. Therefore, the objective of this study is to test whether cyclin/CDKs activate Pak1, an effector of Rac1, whose involvement in the modulation of cell migration and proliferation is well established. Monocyte chemotactic protein 1 (MCP1) induced Pak1 phosphorylation/activation in human aortic smooth muscle cells (HASMCs) in a delayed time-dependent manner. MCP1 also stimulated F-actin stress fiber formation in a delayed manner in HASMCs, as well as the migration and proliferation of these cells. Inhibition of Pak1 suppressed MCP1-induced HASMC F-actin stress fiber formation, migration, and proliferation. MCP1 induced cyclin D1 expression as well as CDK6 and CDK4 activities, and these effects were dependent on activation of NFATc1. Depletion of NFATc1, cyclin D1, CDK6, or CDK4 levels attenuated MCP1-induced Pak1 phosphorylation/activation and resulted in decreased HASMC F-actin stress fiber formation, migration, and proliferation. CDK4, which appeared to be activated downstream of CDK6, formed a complex with Pak1 in response to MCP1. MCP1 also activated Rac1 in a time-dependent manner, and depletion/inhibition of its levels/activation abrogated MCP1-induced NFATc1-cyclin D1-CDK6-CDK4-Pak1 signaling and, thereby, decreased HASMC F-actin stress fiber formation, migration, and proliferation. In addition, smooth muscle-specific deletion of NFATc1 led to decreased cyclin D1 expression and CDK6, CDK4, and Pak1 activities, resulting in reduced neointima formation in response to injury. Thus, these observations reveal that Pak1 is a downstream effector of CDK4 and Rac1-dependent, NFATc1-mediated cyclin D1 expression and CDK6 activity mediate this effect. In addition, smooth muscle-specific deletion of NFATc1 prevented the capacity of vascular smooth muscle cells for MCP-1-induced activation of the cyclin D1-CDK6-CDK4-Pak1 signaling axis, affecting their migration and proliferation in vitro and injury-induced neointima formation in vivo.
Collapse
|
50
|
Kundumani-Sridharan V, Dyukova E, Hansen DE, Rao GN. 12/15-Lipoxygenase mediates high-fat diet-induced endothelial tight junction disruption and monocyte transmigration: a new role for 15(S)-hydroxyeicosatetraenoic acid in endothelial cell dysfunction. J Biol Chem 2013; 288:15830-42. [PMID: 23589307 DOI: 10.1074/jbc.m113.453290] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
A convincing body of evidence suggests that 12/15-lipoxygenase (12/15-LO) plays a role in atherosclerosis. However, the mechanisms of its involvement in the pathogenesis of this disease are not clear. Therefore, the purpose of this study is to understand the mechanisms by which 12/15-LO mediates endothelial dysfunction. 15(S)-Hydroxyeicosatetraenoic acid (15(S)-HETE), the major 12/15-LO metabolite of arachidonic acid (AA), induced endothelial barrier permeability via Src and Pyk2-dependent zonula occluden (ZO)-2 tyrosine phosphorylation and its dissociation from the tight junction complexes. 15(S)-HETE also stimulated macrophage adhesion to the endothelial monolayer in Src and Pyk2-dependent manner. Ex vivo studies revealed that exposure of arteries from WT mice to AA or 15(S)-HETE led to Src-Pyk2-dependent ZO-2 tyrosine phosphorylation, tight junction disruption, and macrophage adhesion, whereas the arteries from 12/15-LO knock-out mice are protected from these effects of AA. Feeding WT mice with a high-fat diet induced the expression of 12/15-LO in the arteries leading to tight junction disruption and macrophage adhesion and deletion of the 12/15-LO gene disallowed these effects. Thus, the findings of this study provide the first evidence of the role of 12/15-LO and its AA metabolite, 15(S)-HETE, in high-fat diet-induced endothelial tight junction disruption and macrophage adhesion, the crucial events underlying the pathogenesis of atherosclerosis.
Collapse
|