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Fang H, Cao Y, Zhang J, Wang X, Li M, Hong Z, Wu Z, Fang M. Lipidome remodeling activities of DPA-EA in palmitic acid-stimulated HepG2 cells and the in vivo anti-obesity effect of the DPA-EA and DHA-EA mixture prepared from algae oil. Front Pharmacol 2023; 14:1146276. [PMID: 37063272 PMCID: PMC10090563 DOI: 10.3389/fphar.2023.1146276] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 03/15/2023] [Indexed: 03/31/2023] Open
Abstract
Background: The nuclear receptor Nur77 has been demonstrated to play a vital role in the inflammatory response and cellular metabolisms, and its ligands exhibit efficacy in the treatment of inflammation-related diseases (e.g., improving mouse acute lung injury (ALI) and obesity. Recently, ω-3 polyunsaturated fatty acid-ethanolamine derivatives (ω-3 PUFA-EAs), including DPA-EA and DHA-EA, have been reported as new Nur77-targeting anti-inflammatory agents. However, the lipid-lowering effect of ω-3 PUFA-EAs is still unknown, and lipid profile changes induced by Nur77-targeting anti-inflammatory agents also remain unclear.Objective: This study aimed to evaluate the lipid-lowering effect and the underlying mechanism of DPA-EA acting as Nur77-targeting anti-inflammatory agents. It also aimed to investigate the in vitro and in vivo lipid-lowering effects of the DPA-EA and DHA-EA mixture prepared from algae oil.Methods: The in vitro lipid-lowing effect of DPA-EA and its mixture with DHA-EA was first evaluated in palmitic acid-stimulated HepG2 Cells. To confirm the lipid-lowering effect and explore the underlying mechanism, we performed untargeted lipidomic analysis using ultra-performance liquid chromatography/triple quadrupole-time-of-flight (TOF) mass spectrometry coupled with multivariate statistical analysis, with another Nur77-targeting anti-inflammatory compound Celastrol (Cel) as a reference. Finally, we examined the anti-obesity effect of the DPA-EA and DHA-EA mixture synthesized from algae oil in a high-fat diet (HFD)-fed mice model.Results: DPA-EA significantly alleviated lipid accumulation with lower toxicity than Celastrol. Nur77-targeting compounds DPA-EA and Celastrol could simultaneously reduce 14 lipids (9 TGs, 2 PCs, 1 PA, 1 SM, and 1 LacCer) and increase 13 lipids (4 DGs, 6 LPEs, 2 PEs, and 1PC) in Pal-stimulated HepG2 cells. However, Cer lipids were more sensitive to DPA-EA, while the over-downregulation of SM lipids might be associated with the off-target toxicity of Celastrol. The mixture of DPA-EA and DHA-EA synthesized from algae oil could significantly decrease TG, TC, and LDL levels and increase HDL levels in HFD-fed mice, exerting an excellent anti-obesity effect.Conclusion: Nur77-targeting anti-inflammatory compound DAP-EA could promote the hydrolysis of PEs and TGs to ameliorate lipid accumulation. The DPA-EA and DHA-EA mixture prepared from algae oil might be a potential therapeutic agent for obesity and other inflammation-related diseases.
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Affiliation(s)
- Hua Fang
- Technical Innovation Center for Utilization of Marine Biological Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Yin Cao
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Jianyu Zhang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Xiumei Wang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Mengyu Li
- Technical Innovation Center for Utilization of Marine Biological Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
- College of Ocean Food and Biological Engineering, Jimei University, Xiamen, China
| | - Zhuan Hong
- Technical Innovation Center for Utilization of Marine Biological Resources, Third Institute of Oceanography, Ministry of Natural Resources, Xiamen, China
| | - Zhen Wu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
| | - Meijuan Fang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen, China
- *Correspondence: Meijuan Fang,
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Fang H, Zhang J, Ao M, He F, Chen W, Qian Y, Zhang Y, Xu Y, Fang M. Synthesis and discovery of ω-3 polyunsaturated fatty acid- alkanolamine (PUFA-AA) derivatives as anti-inflammatory agents targeting Nur77. Bioorg Chem 2020; 105:104456. [PMID: 33217634 DOI: 10.1016/j.bioorg.2020.104456] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 09/07/2020] [Accepted: 11/01/2020] [Indexed: 12/16/2022]
Abstract
In this work, three series of ω-3 polyunsaturated fatty acid-alkanolamine derivatives (PUFA-AAs) were synthesized, characterized and their anti-inflammatory activity in vivo was evaluated. Compounds 4a, 4f, and 4k exhibited marked anti-inflammatory activity in LPS-stimulated RAW 264.7 cells. The most promising compound 4k dose-dependently suppressed the cytokines with IC50 values in the low micromolar range. Further, 4k exhibited potential in vitro Nur77-binding affinity (Kd = 6.99 × 10-6 M) which is consistent with the result of docking studies. Next, the anti-inflammatory mechanism of 4k was found to be through NF-κB signal pathway in a Nur77-dependent manner. Moreover, we also observed 4k significantly inhibited LPS-induced expression of cytokines (IL-6, TNF-α, and IL-1β) through suppressing NF-κB activation and attenuated LPS-induced inflammation in mouse acute lung injury (ALI) model. In conclusion, the study strongly suggests that the PUFA-AA derivatives can be particularly as new Nur77 mediators for further treatment in inflammatory diseases.
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Affiliation(s)
- Hua Fang
- Third Institute of Oceanography, Ministry of Natural Resources, Technical Innovation Center for Utilization of Marine Biological Resources, Ministry of Natural Resources, Xiamen 361005, China
| | - Jianyu Zhang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China
| | - Mingtao Ao
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China
| | - Fengming He
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China
| | - Weizhu Chen
- Third Institute of Oceanography, Ministry of Natural Resources, Technical Innovation Center for Utilization of Marine Biological Resources, Ministry of Natural Resources, Xiamen 361005, China
| | - Yuqing Qian
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China
| | - Yuxiang Zhang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China
| | - Yang Xu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Meijuan Fang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research and State Key Laboratory of Cellular Stress Biology, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
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Maucher D, Schmidt B, Kuhlmann K, Schumann J. Polyunsaturated Fatty Acids of Both the Omega-3 and the Omega-6 Family Abrogate the Cytokine-Induced Upregulation of miR-29a-3p by Endothelial Cells. Molecules 2020; 25:molecules25194466. [PMID: 33003296 PMCID: PMC7583866 DOI: 10.3390/molecules25194466] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 09/17/2020] [Accepted: 09/27/2020] [Indexed: 11/16/2022] Open
Abstract
Cellular processes fundamentally depend on protein expression control. At this, protein expression is regulated on the transcriptional and the post-transcriptional level. PUFAs are already known to affect gene transcription. The present study was conducted to answer the question whether PUFAs are also able to impact on the miRNA-mediated post-transcriptional fine-tuning of mRNA copy numbers. To this end, cellular miRNA profiles were screened by means of next-generation sequencing and NanoString analysis to compare PUFA-enriched to unsupplemented endothelial cells exposed to an inflammatory milieu. Validation took place by droplet digital PCR, allowing for an absolute quantification of RNA copy numbers. The analyses revealed that the stimulation-induced upregulation of miR-29a-3p is blocked by PUFA enrichment of endothelial cells. What is more, mRNA copy numbers of miR-29a-3p targets, namely the coagulation factors PAI-1, TF, and vWF, as well as the proinflammatory cytokines IL-1β, IL-6, and IL-8, were reduced in PUFA-enriched endothelial cells compared to unsupplemented cells, counteracting the stimulatory effect of an inflammatory environment. These data hint toward a new mechanism of action by which PUFAs modulate the functionality of endothelial cells. Apparently, the inflammation-modulating properties of PUFAs are also mediated at the post-transcriptional level.
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Affiliation(s)
| | | | | | - Julia Schumann
- Correspondence: ; Tel.: +49-345-5571776; Fax: +49-345-5571781
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Hellwing C, Schoeniger A, Roessler C, Leimert A, Schumann J. Lipid raft localization of TLR2 and its co-receptors is independent of membrane lipid composition. PeerJ 2018; 6:e4212. [PMID: 29312832 PMCID: PMC5757419 DOI: 10.7717/peerj.4212] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 12/09/2017] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Toll like receptors (TLRs) are an important and evolutionary conserved class of pattern recognition receptors associated with innate immunity. The recognition of Gram-positive cell wall constituents strongly depends on TLR2. In order to be functional, TLR2 predominantly forms a heterodimer with TLR1 or TLR6 within specialized membrane microdomains, the lipid rafts. The membrane lipid composition and the physicochemical properties of lipid rafts are subject to modification by exogenous fatty acids. Previous investigations of our group provide evidence that macrophage enrichment with polyunsaturated fatty acids (PUFA) induces a reordering of lipid rafts and non-rafts based on the incorporation of supplemented PUFA as well as their elongation and desaturation products. METHODS In the present study we investigated potential constraining effects of membrane microdomain reorganization on the clustering of TLR2 with its co-receptors TLR1 and TLR6 within lipid rafts. To this end, RAW264.7 macrophages were supplemented with either docosahexaenoic acid (DHA) or arachidonic acid (AA) and analyzed for receptor expression and microdomain localization in context of TLR stimulation. RESULTS AND CONCLUSIONS Our analyses showed that receptor levels and microdomain localization were unchanged by PUFA supplementation. The TLR2 pathway, in contrast to the TLR4 signaling cascade, is not affected by exogenous PUFA at the membrane level.
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Affiliation(s)
- Christine Hellwing
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Halle (Saale), Germany
| | - Axel Schoeniger
- Institute of Biochemistry, Faculty of Veterinary Medicine, University of Leipzig, Leipzig, Germany
| | - Claudia Roessler
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Halle (Saale), Germany
| | - Anja Leimert
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Halle (Saale), Germany
| | - Julia Schumann
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Halle (Saale), Germany
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Trommer S, Leimert A, Bucher M, Schumann J. Impact of Unsaturated Fatty Acids on Cytokine-Driven Endothelial Cell Dysfunction. Int J Mol Sci 2017; 18:ijms18122739. [PMID: 29258201 PMCID: PMC5751340 DOI: 10.3390/ijms18122739] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 12/08/2017] [Accepted: 12/15/2017] [Indexed: 12/21/2022] Open
Abstract
Polyunsaturated fatty acids (PUFA) are reported to exert prophylactic and acute therapeutic effects in diseases linked to endothelial dysfunction. In the present study, the consequences of a PUFA enrichment of endothelial cells (cell line TIME) on cell viability, expression of the cytokines interleukin-6 (IL-6), interleukin-8 (IL-8), granulocyte-macrophage colony-stimulating factor (GM-CSF), and monocyte chemoattractant protein 1 (MCP-1), synthesis of the adhesion molecules intercellular adhesion molecule 1 (ICAM-1) and vascular adhesion molecule 1 (VCAM-1), and production of the coagulation factors plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor (vWF), and tissue factor (TF) was analyzed in parallel. PUFA of both the n3 and the n6 family were investigated in a physiologically relevant concentration of 15 µM, and experiments were performed in both the presence and the absence of the pro-inflammatory cytokines interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ). Supplementation of the culture medium with particular fatty acids was found to have a promoting effect on cellular production of the cytokines IL-6, IL-8, GM-CSF, and MCP-1. Further on, PUFA treatment in the absence of a stimulant diminished the percentage of endothelial cells positive for ICAM-1, and adversely affected the stimulation-induced upregulation of VCAM-1. Cell viability and production of coagulation factors were not or only marginally affected by supplemented fatty acids. Altogether, the data indicate that PUFA of either family are only partially able to counterbalance the destructive consequences of an endothelial dysfunction.
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Affiliation(s)
- Simon Trommer
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), 06120 Halle (Saale), Germany.
| | - Anja Leimert
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), 06120 Halle (Saale), Germany.
| | - Michael Bucher
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), 06120 Halle (Saale), Germany.
| | - Julia Schumann
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), 06120 Halle (Saale), Germany.
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Schoeniger A, Fuhrmann H, Schumann J. LPS- or Pseudomonas aeruginosa-mediated activation of the macrophage TLR4 signaling cascade depends on membrane lipid composition. PeerJ 2016; 4:e1663. [PMID: 26870615 PMCID: PMC4748739 DOI: 10.7717/peerj.1663] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 01/15/2016] [Indexed: 01/12/2023] Open
Abstract
It is well known that PUFA impede the LPS-mediated activation of the transcription factor NFkappaB. However, the underlying mode of action has not been clarified yet. To address this issue in a comprehensive approach, we used the monocyte/macrophage cell line RAW264.7 to investigate the consequences of a PUFA supplementation on the TLR4 pathway with a focus on (i) the gene expression of TLR4 itself as well as of its downstream mediators, (ii) the membrane microdomain localization of TLR4 and CD14, (iii) the stimulation-induced interaction of TLR4 and CD14. Our data indicate that the impairment of the TLR4-mediated cell activation by PUFA supplementation is not due to changes in gene expression of mediator proteins of the signaling cascade. Rather, our data provide evidence that the PUFA enrichment of macrophages affects the TLR4 pathway at the membrane level. PUFA incorporation into membrane lipids induces a reordering of membrane microdomains thereby affecting cellular signal transduction. It is important to note that this remodeling of macrophage rafts has no adverse effect on cell viability. Hence, microdomain disruption via macrophage PUFA supplementation has a potential as non-toxic strategy to attenuate inflammatory signaling.
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Affiliation(s)
- Axel Schoeniger
- Faculty of Veterinary Medicine, Institute of Physiological Chemistry, University of Leipzig, Leipzig, Germany
| | - Herbert Fuhrmann
- Faculty of Veterinary Medicine, Institute of Physiological Chemistry, University of Leipzig, Leipzig, Germany
| | - Julia Schumann
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Halle (Saale), Germany
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7
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Schumann J. Does plasma membrane lipid composition impact the miRNA-mediated regulation of vascular inflammation? Med Hypotheses 2016; 88:57-9. [PMID: 26880639 DOI: 10.1016/j.mehy.2016.01.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Revised: 01/08/2016] [Accepted: 01/19/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND Both PUFA and miRNAs are believed to be of importance in vascular diseases. On the one hand diverse nutrition societies recommend PUFA consumption to dampen inflammatory processes. On the other hand scientists intensify efforts to use miRNAs for diagnostics or therapy in context of vascular disorders. PRESENTATION OF THE HYPOTHESIS There might be is a causal link between the plasma membrane lipid composition and the miRNA expression of monocytes and endothelial cells. PUFA enrichment of cells may affect the type and the amount of particular miRNAs produced. In this way dietary fatty acids are supposed to impact the miRNA-mediated regulation of vascular inflammatory processes. PROPOSED EXPERIMENTAL SETTING TO TEST THE HYPOTHESIS PUFA-supplemented monocytes and endothelial cells are analyzed with respect to membrane fatty acid patterns, typical markers of vascular inflammation and miRNA expression. Experiments are performed both for undifferentiated/unstimulated as well as for differentiated/stimulated cells. Verification of identified miRNA targets is performed by means of mimics/antagomirs. IMPLICATIONS OF THE HYPOTHESIS Innovative mechanism of action, which could point the way to a new understanding of the PUFA-mediated modulation of cellular signal transduction. If confirmed experimentally, it might stimulate vascular inflammation research and immunologic lipid science, hence, acting as source of inspiration for future therapeutic interventions in vascular diseases.
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Affiliation(s)
- Julia Schumann
- Clinic for Anesthesiology and Surgical Intensive Care, University Hospital Halle (Saale), Franzosenweg 1a, 06112 Halle (Saale), Germany.
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Ferramosca A, Zara V. Dietary fat and hepatic lipogenesis: mitochondrial citrate carrier as a sensor of metabolic changes. Adv Nutr 2014; 5:217-25. [PMID: 24829468 PMCID: PMC4013174 DOI: 10.3945/an.113.004762] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Citrate carrier (CIC) is an integral protein of the inner mitochondrial membrane that has a fundamental role in hepatic intermediary metabolism. Its primary function is to catalyze the transport of citrate from mitochondria, where this molecule is formed, to cytosol, where this molecule is used for fatty acid (FA) and cholesterol synthesis. Therefore, mitochondrial CIC acts upstream of cytosolic lipogenic reactions, and its regulation is particularly important in view of the modulation of hepatic lipogenesis. Although a great deal of data are currently available on the dietary modulation of cytosolic lipogenic enzymes, little is known about the nutritional regulation of CIC transport activity. In this review, we describe the differential effects of distinct FAs present in the diet on the activity of mitochondrial CIC. In particular, polyunsaturated FAs were powerful modulators of the activity of mitochondrial CIC by influencing its expression through transcriptional and posttranscriptional mechanisms. On the contrary, saturated and monounsaturated FAs did not influence mitochondrial CIC activity. Moreover, variations in CIC activity were connected to similar alterations in the metabolic pathways to which the transported citrate is channeled. Therefore, CIC may be considered as a sensor for changes occurring inside the hepatocyte and may represent an important target for the regulation of hepatic lipogenesis. The crucial role of this protein is reinforced by the recent discovery of its involvement in other cellular processes, such as glucose-stimulated insulin secretion, inflammation, tumorigenesis, genome stability, and sperm metabolism.
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Affiliation(s)
| | - Vincenzo Zara
- Department of Biological and Environmental Sciences and Technologies, University of Salento, Lecce, Italy
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Conjugated linoleic acid suppresses IRF3 activation via modulation of CD14. J Nutr Biochem 2013; 24:920-8. [DOI: 10.1016/j.jnutbio.2012.06.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 05/31/2012] [Accepted: 06/08/2012] [Indexed: 11/18/2022]
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Transcriptional Regulation of the Mitochondrial Citrate and Carnitine/Acylcarnitine Transporters: Two Genes Involved in Fatty Acid Biosynthesis and β-oxidation. BIOLOGY 2013; 2:284-303. [PMID: 24832661 PMCID: PMC4009865 DOI: 10.3390/biology2010284] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/18/2013] [Accepted: 01/23/2013] [Indexed: 12/17/2022]
Abstract
Transcriptional regulation of genes involved in fatty acid metabolism is considered the major long-term regulatory mechanism controlling lipid homeostasis. By means of this mechanism, transcription factors, nutrients, hormones and epigenetics control not only fatty acid metabolism, but also many metabolic pathways and cellular functions at the molecular level. The regulation of the expression of many genes at the level of their transcription has already been analyzed. This review focuses on the transcriptional control of two genes involved in fatty acid biosynthesis and oxidation: the citrate carrier (CIC) and the carnitine/ acylcarnitine/carrier (CAC), which are members of the mitochondrial carrier gene family, SLC25. The contribution of tissue-specific and less tissue-specific transcription factors in activating or repressing CIC and CAC gene expression is discussed. The interaction with drugs of some transcription factors, such as PPAR and FOXA1, and how this interaction can be an attractive therapeutic approach, has also been evaluated. Moreover, the mechanism by which the expression of the CIC and CAC genes is modulated by coordinated responses to hormonal and nutritional changes and to epigenetics is highlighted.
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Eyre H, Baune BT. Neuroplastic changes in depression: a role for the immune system. Psychoneuroendocrinology 2012; 37:1397-416. [PMID: 22525700 DOI: 10.1016/j.psyneuen.2012.03.019] [Citation(s) in RCA: 210] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Revised: 03/15/2012] [Accepted: 03/22/2012] [Indexed: 12/12/2022]
Abstract
Accumulating evidence suggests that there is a rich cross-talk between the neuroimmune system and neuroplasticity mechanisms under both physiological conditions and pathophysiological conditions in depression. Anti-neuroplastic changes which occur in depression include a decrease in proliferation of neural stem cells (NSCs), decreased survival of neuroblasts and immature neurons, impaired neurocircuitry (cortical-striatal-limbic circuits), reduced levels of neurotrophins, reduced spine density and dendritic retraction. Since both humoral and cellular immune factors have been implicated in neuroplastic processes, in this review we present a model suggesting that neuroplastic processes in depression are mediated through various neuroimmune mechanisms. The review puts forward a model in that both humoral and cellular neuroimmune factors are involved with impairing neuroplasticity under pathophysiological conditions such as depression. Specifically, neuroimmune factors including interleukin (IL)-1, IL-6, tumour necrosis factor (TNF)-α, CD4⁺CD25⁺T regulatory cells (T reg), self-specific CD4⁺T cells, monocyte-derived macrophages, microglia and astrocytes are shown to be vital to processes of neuroplasticity such as long-term potentiation (LTP), NSC survival, synaptic branching, neurotrophin regulation and neurogenesis. In rodent models of depression, IL-1, IL-6 and TNF are associated with reduced hippocampal neurogenesis; mechanisms which are associated with this include the stress-activated protein kinase (SAPK)/Janus Kinase (JNK) pathway, hypoxia-inducible factors (HIF)-1α, JAK-Signal Transducer and Activator of Transcription (STAT) pathway, mitogen-activated protein kinase (MAPK)/cAMP responsive element binding protein (CREB) pathway, Ras-MAPK, PI-3 kinase, IKK/nuclear factor (NF)-κB and TGFβ activated kinase-1 (TAK-1). Neuroimmunological mechanisms have an active role in the neuroplastic changes associated with depression. Since therapies in depression, including antidepressants (AD), omega-3 polyunsaturated fatty acids (PUFAs) and physical activity exert neuroplasticity-enhancing effects potentially mediated by neuroimmune mechanisms, the immune system might serve as a promising target for interventions in depression.
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Affiliation(s)
- Harris Eyre
- Discipline of Psychiatry, School of Medicine, University of Adelaide, North Terrace, Adelaide, South Australia 5005, Australia
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Adolph S, Schoeniger A, Fuhrmann H, Schumann J. Unsaturated fatty acids as modulators of macrophage respiratory burst in the immune response against Rhodococcus equi and Pseudomonas aeruginosa. Free Radic Biol Med 2012; 52:2246-53. [PMID: 22658994 DOI: 10.1016/j.freeradbiomed.2012.04.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 03/23/2012] [Accepted: 04/02/2012] [Indexed: 10/28/2022]
Abstract
In this paper, using the monocyte/macrophage cell line RAW264.7, we systematically investigate the impact of macrophage enrichment with unsaturated fatty acids on cellular radical synthesis. We found that the intracellular production of reactive nitrogen and oxygen intermediates depends on the activation status of the macrophages. For unstimulated macrophages PUFA enrichment resulted in an increase in cellular radical synthesis. For stimulated macrophages, instead, an impeding action of unsaturated fatty acids on the respiratory burst could be seen. Of particular importance, the impact of unsaturated fatty acids on the macrophage respiratory burst was also observed in RAW264.7 cells cocultivated with viable bacteria of the species Rhodococcus equi or Pseudomonas aeruginosa. PUFA supplementation of macrophages in the presence of R. equi or P. aeruginosa reduced the pathogen-stimulated synthesis of reactive nitrogen and oxygen intermediates. Furthermore, the unsaturated fatty acids were found to impede the expression of the myeloperoxidase gene and to reduce the activity of the enzyme. Hence, our data provide indications of a possible value of PUFA application to people suffering from chronic infections with R. equi and P. aeruginosa as a concomitant treatment to attenuate an excessive respiratory burst.
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Affiliation(s)
- Stephanie Adolph
- Faculty of Veterinary Medicine, Institute of Physiological Chemistry, University of Leipzig, 04103 Leipzig, Germany
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The impact of membrane lipid composition on macrophage activation in the immune defense against Rhodococcus equi and Pseudomonas aeruginosa. Int J Mol Sci 2011; 12:7510-28. [PMID: 22174614 PMCID: PMC3233420 DOI: 10.3390/ijms12117510] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 10/17/2011] [Accepted: 10/26/2011] [Indexed: 11/29/2022] Open
Abstract
Nutritional fatty acids are known to have an impact on membrane lipid composition of body cells, including cells of the immune system, thus providing a link between dietary fatty acid uptake, inflammation and immunity. In this study we reveal the significance of macrophage membrane lipid composition on gene expression and cytokine synthesis thereby highlighting signal transduction processes, macrophage activation as well as macrophage defense mechanisms. Using RAW264.7 macrophages as a model system, we identified polyunsaturated fatty acids (PUFA) of both the n-3 and the n-6 family to down-regulate the synthesis of: (i) the pro-inflammatory cytokines IL-1β, IL-6 and TNF-α; (ii) the co-stimulatory molecule CD86; as well as (iii) the antimicrobial polypeptide lysozyme. The action of the fatty acids partially depended on the activation status of the macrophages. It is particularly important to note that the anti-inflammatory action of the PUFA could also be seen in case of infection of RAW264.7 with viable microorganisms of the genera R. equi and P. aeruginosa. In summary, our data provide strong evidence that PUFA from both the n-3 and the n-6 family down-regulate inflammation processes in context of chronic infections caused by persistent pathogens.
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