1
|
Kadamani KL, Logan SM, Pamenter ME. Does hypometabolism constrain innate immune defense? Acta Physiol (Oxf) 2024; 240:e14091. [PMID: 38288574 DOI: 10.1111/apha.14091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Revised: 11/30/2023] [Accepted: 01/01/2024] [Indexed: 02/24/2024]
Abstract
Many animals routinely make energetic trade-offs to adjust to environmental demands and these trade-offs often have significant implications for survival. For example, environmental hypoxia is commonly experienced by many organisms and is an energetically challenging condition because reduced oxygen availability constrains aerobic energy production, which can be lethal. Many hypoxia-tolerant species downregulate metabolic demands when oxygen is limited; however, certain physiological functions are obligatory and must be maintained despite the need to conserve energy in hypoxia. Of particular interest is immunity (including both constitutive and induced immune functions) because mounting an immune response is among the most energetically expensive physiological processes but maintaining immune function is critical for survival in most environments. Intriguingly, physiological responses to hypoxia and pathogens share key molecular regulators such as hypoxia-inducible factor-1α, through which hypoxia can directly activate an immune response. This raises an interesting question: do hypoxia-tolerant species mount an immune response during periods of hypoxia-induced hypometabolism? Unfortunately, surprisingly few studies have examined interactions between immunity and hypometabolism in such species. Therefore, in this review, we consider mechanistic interactions between metabolism and immunity, as well as energetic trade-offs between these two systems, in hypoxia-tolerant animals but also in other models of hypometabolism, including neonates and hibernators. Specifically, we explore the hypothesis that such species have blunted immune responses in hypometabolic conditions and/or use alternative immune pathways when in a hypometabolic state. Evidence to date suggests that hypoxia-tolerant animals do maintain immunity in low oxygen conditions, but that the sensitivity of immune responses may be blunted.
Collapse
Affiliation(s)
- Karen L Kadamani
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Samantha M Logan
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Matthew E Pamenter
- Department of Biology, University of Ottawa, Ottawa, Ontario, Canada
- University of Ottawa Brain and Mind Research Institute, Ottawa, Ontario, Canada
| |
Collapse
|
2
|
Lopez-Pascual A, Trayhurn P, Martínez JA, González-Muniesa P. Oxygen in Metabolic Dysfunction and Its Therapeutic Relevance. Antioxid Redox Signal 2021; 35:642-687. [PMID: 34036800 DOI: 10.1089/ars.2019.7901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Significance: In recent years, a number of studies have shown altered oxygen partial pressure at a tissue level in metabolic disorders, and some researchers have considered oxygen to be a (macro) nutrient. Oxygen availability may be compromised in obesity and several other metabolism-related pathological conditions, including sleep apnea-hypopnea syndrome, the metabolic syndrome (which is a set of conditions), type 2 diabetes, cardiovascular disease, and cancer. Recent Advances: Strategies designed to reduce adiposity and its accompanying disorders have been mainly centered on nutritional interventions and physical activity programs. However, novel therapies are needed since these approaches have not been sufficient to counteract the worldwide increasing rates of metabolic disorders. In this regard, intermittent hypoxia training and hyperoxia could be potential treatments through oxygen-related adaptations. Moreover, living at a high altitude may have a protective effect against the development of abnormal metabolic conditions. In addition, oxygen delivery systems may be of therapeutic value for supplying the tissue-specific oxygen requirements. Critical Issues: Precise in vivo methods to measure oxygenation are vital to disentangle some of the controversies related to this research area. Further, it is evident that there is a growing need for novel in vitro models to study the potential pathways involved in metabolic dysfunction to find appropriate therapeutic targets. Future Directions: Based on the existing evidence, it is suggested that oxygen availability has a key role in obesity and its related comorbidities. Oxygen should be considered in relation to potential therapeutic strategies in the treatment and prevention of metabolic disorders. Antioxid. Redox Signal. 35, 642-687.
Collapse
Affiliation(s)
- Amaya Lopez-Pascual
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,Neuroendocrine Cell Biology, Lund University Diabetes Centre, Lund University, Malmö, Sweden
| | - Paul Trayhurn
- Obesity Biology Unit, University of Liverpool, Liverpool, United Kingdom.,Clore Laboratory, The University of Buckingham, Buckingham, United Kingdom
| | - J Alfredo Martínez
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Pamplona, Spain.,CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain.,Precision Nutrition and Cardiometabolic Health, IMDEA Food, Madrid Institute for Advanced Studies, Madrid, Spain
| | - Pedro González-Muniesa
- Department of Nutrition, Food Science and Physiology, School of Pharmacy and Nutrition, Centre for Nutrition Research, University of Navarra, Pamplona, Spain.,IdiSNA, Navarra Institute for Health Research, Pamplona, Spain.,CIBERobn Physiopathology of Obesity and Nutrition, Centre of Biomedical Research Network, ISCIII, Madrid, Spain
| |
Collapse
|
3
|
Hutami IR, Izawa T, Khurel-Ochir T, Sakamaki T, Iwasa A, Tanaka E. Macrophage Motility in Wound Healing Is Regulated by HIF-1α via S1P Signaling. Int J Mol Sci 2021; 22:ijms22168992. [PMID: 34445695 PMCID: PMC8396560 DOI: 10.3390/ijms22168992] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Revised: 08/14/2021] [Accepted: 08/18/2021] [Indexed: 12/20/2022] Open
Abstract
Accumulating evidence indicates that the molecular pathways mediating wound healing induce cell migration and localization of cytokines to sites of injury. Macrophages are immune cells that sense and actively respond to disturbances in tissue homeostasis by initiating, and subsequently resolving, inflammation. Hypoxic conditions generated at a wound site also strongly recruit macrophages and affect their function. Hypoxia inducible factor (HIF)-1α is a transcription factor that contributes to both glycolysis and the induction of inflammatory genes, while also being critical for macrophage activation. For the latter, HIF-1α regulates sphingosine 1-phosphate (S1P) to affect the migration, activation, differentiation, and polarization of macrophages. Recently, S1P and HIF-1α have received much attention, and various studies have been performed to investigate their roles in initiating and resolving inflammation via macrophages. It is hypothesized that the HIF-1α/S1P/S1P receptor axis is an important determinant of macrophage function under inflammatory conditions and during disease pathogenesis. Therefore, in this review, biological regulation of monocytes/macrophages in response to circulating HIF-1α is summarized, including signaling by S1P/S1P receptors, which have essential roles in wound healing.
Collapse
Affiliation(s)
- Islamy Rahma Hutami
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
- Department of Orthodontics, Faculty of Dentistry, Sultan Agung Islamic University, Semarang 50112, Indonesia
| | - Takashi Izawa
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
- Department of Orthodontics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama 700-8525, Japan
- Correspondence: ; Tel.: +81-86-235-6691; Fax: +81-88-235-6694
| | - Tsendsuren Khurel-Ochir
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
| | - Takuma Sakamaki
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
| | - Akihiko Iwasa
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
| | - Eiji Tanaka
- Department of Orthodontics and Dentofacial Orthopedics, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8504, Japan; (I.R.H.); (T.K.-O.); (T.S.); (A.I.); (E.T.)
| |
Collapse
|
4
|
Zeng W, Xing Z, Tan M, Wu Y, Zhang C. Propofol regulates activated macrophages metabolism through inhibition of ROS-mediated GLUT1 expression. Inflamm Res 2021; 70:473-481. [PMID: 33751130 DOI: 10.1007/s00011-021-01449-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Revised: 02/02/2021] [Accepted: 03/04/2021] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE Activated macrophages undergo a metabolic shift from oxidative phosphorylation (OXPHOS) to aerobic glycolysis, which plays a critical role in inflammation. Increasing evidence suggests the important role of propofol in the regulation of inflammatory response and metabolism, but the effect of propofol on the metabolic shift in macrophage, and the mechanisms involved remain unclear. METHODS The effect of propofol on the metabolic switch was analyzed by extracellular acidification rate and oxygen consumption rate assays. The effect of propofol on glycolysis was analyzed by lactate and glucose uptake assay. The mRNA, protein, cell surface levels of glucose transporter 1 (GLUT1) and the silencing of GLUT1 were employed to understand the effects of GLUT1-mediated metabolism by propofol. Finally, to understand the antioxidation of propofol on the regulation of metabolism, the reactive oxygen species (ROS) production and NADPH activity were performed. RESULTS We show that propofol can change the metabolic pathway switch from aerobic glycolysis to OXPHOS in LPS-activated macrophages. Moreover, propofol suppresses aerobic glycolysis via inhibited GLUT1-mediated glucose uptake. Furthermore, we show that propofol reduces ROS overproduction, which in turn inhibits GLUT1 expression. Finally, we find that propofol reduces ROS production via inhibits NADPH activity. CONCLUSION These findings shed light on the function and mechanism of propofol in the metabolic switch and highlight the importance of targeting metabolism by propofol in the clinical medication of inflammatory diseases.
Collapse
Affiliation(s)
- Wei Zeng
- Department of Anesthesiology, Affiliated Boai Hospital of Zhongshan, Southern Medical University, Guangdong, 528400, China
| | - Zeting Xing
- Department of Anesthesiology, Affiliated Boai Hospital of Zhongshan, Southern Medical University, Guangdong, 528400, China
| | - Meiyun Tan
- Department of Anesthesiology, Affiliated Boai Hospital of Zhongshan, Southern Medical University, Guangdong, 528400, China
| | - Yanwen Wu
- Department of Anesthesiology, Affiliated Boai Hospital of Zhongshan, Southern Medical University, Guangdong, 528400, China
| | - Chunyuan Zhang
- Department of Anesthesiology, Affiliated Boai Hospital of Zhongshan, Southern Medical University, Guangdong, 528400, China.
| |
Collapse
|
5
|
Gomes A, Leite F, Ribeiro L. Adipocytes and macrophages secretomes coregulate catecholamine-synthesizing enzymes. Int J Med Sci 2021; 18:582-592. [PMID: 33437193 PMCID: PMC7797554 DOI: 10.7150/ijms.52219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 11/09/2020] [Indexed: 12/13/2022] Open
Abstract
Obesity associates with macrophage accumulation in adipose tissue where these infiltrating cells interact with adipocytes and contribute to the systemic chronic metabolic inflammation present in immunometabolic diseases. Tyrosine hydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) are two of the main enzymes of catecholamines (CA) synthesis. Adipocytes and macrophages produce, secrete and respond to CA, but the regulation of their synthesis in the interplay between immune and metabolic systems remains unknown. A model of indirect cell coculture with conditioned medium (CM) from RAW 264.7 macrophages with or without LPS-activation and 3T3-L1 adipocytes and preadipocytes was established to study the effect of cellular secretomes on the expression of the above enzymes. During the adipocyte differentiation process, we found a decrease of TH and PNMT expression. The secretome from LPS-activated macrophages downregulated TH and PNMT expression in preadipocytes, but not in mature adipocytes. Mature adipocytes CM induced a decrease of PNMT levels in RAW 264.7 macrophages. Pre and mature adipocytes showed a similar pattern of TH, PNMT and peroxisome proliferator-activated receptor gamma expression after exposure to pro and anti-inflammatory cytokines. We evidenced macrophages and adipocytes coregulate the expression of CA synthesis enzymes through secretome, with non-inflammatory signaling networks possibly being involved. Mediators released by macrophages seem to equally affect CA production by adipocytes, while adipocytes secretome preferentially affect AD production by macrophages. CA synthesis seems to be more determinant in early stages of adipogenic differentiation. Our results suggest that CA are key signaling molecules in the regulation of immune-metabolic crosstalk within the adipose tissue.
Collapse
Affiliation(s)
- Andreia Gomes
- Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine, University of Porto. Alameda Prof Hernâni Monteiro, 4200-319 Porto, Portugal
- i3S, Instituto de Investigação e Inovação em Saúde, University of Porto. Rua Alfredo Allen 208, 4200-135 Porto, Portugal
| | - Fernanda Leite
- Department of Clinical Haematology, Centro Hospitalar Universitário of Porto, Largo Professor Abel Salazar, 4099-001, Porto, Portugal
- UMIB/ICBAS - Unit for Multidisciplinary Investigation in Biomedicine- Institutode Ciências Biomédicas Abel Salazar, University of Porto, Porto, Portugal
| | - Laura Ribeiro
- Department of Biomedicine, Unit of Biochemistry, Faculty of Medicine, University of Porto. Alameda Prof Hernâni Monteiro, 4200-319 Porto, Portugal
- i3S, Instituto de Investigação e Inovação em Saúde, University of Porto. Rua Alfredo Allen 208, 4200-135 Porto, Portugal
- Department of Public Health and Forensic Sciences, and Medical Education, Faculty of Medicine, University of Porto. Alameda Prof Hernâni Monteiro, 4200-319 Porto, Portugal
| |
Collapse
|
6
|
Hypoxia and HIF Signaling: One Axis with Divergent Effects. Int J Mol Sci 2020; 21:ijms21165611. [PMID: 32764403 PMCID: PMC7460602 DOI: 10.3390/ijms21165611] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/31/2020] [Accepted: 08/03/2020] [Indexed: 12/15/2022] Open
Abstract
The correct concentration of oxygen in all tissues is a hallmark of cellular wellness, and the negative regulation of oxygen homeostasis is able to affect the cells and tissues of the whole organism. The cellular response to hypoxia is characterized by the activation of multiple genes involved in many biological processes. Among them, hypoxia-inducible factor (HIF) represents the master regulator of the hypoxia response. The active heterodimeric complex HIF α/β, binding to hypoxia-responsive elements (HREs), determines the induction of at least 100 target genes to restore tissue homeostasis. A growing body of evidence demonstrates that hypoxia signaling can act by generating contrasting responses in cells and tissues. Here, this dual and controversial role of hypoxia and the HIF signaling pathway is discussed, with particular reference to the effects induced on the complex activities of the immune system and on mechanisms determining cell and tissue responses after an injury in both acute and chronic human diseases related to the heart, lung, liver, and kidney.
Collapse
|
7
|
Li B, Po SS, Zhang B, Bai F, Li J, Qin F, Liu N, Sun C, Xiao Y, Tu T, Zhou S, Liu Q. Metformin regulates adiponectin signalling in epicardial adipose tissue and reduces atrial fibrillation vulnerability. J Cell Mol Med 2020; 24:7751-7766. [PMID: 32441464 PMCID: PMC7348162 DOI: 10.1111/jcmm.15407] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 03/31/2020] [Accepted: 04/22/2020] [Indexed: 12/26/2022] Open
Abstract
Epicardial adipose tissue (EAT) remodelling is closely related to the pathogenesis of atrial fibrillation (AF). We investigated whether metformin (MET) prevents AF‐dependent EAT remodelling and AF vulnerability in dogs. A canine AF model was developed by 6‐week rapid atrial pacing (RAP), and electrophysiological parameters were measured. Effective refractory periods (ERP) were decreased in the left and right atrial appendages as well as in the left atrium (LA) and right atrium (RA). MET attenuated the RAP‐induced increase in ERP dispersion, cumulative window of vulnerability, AF inducibility and AF duration. RAP increased reactive oxygen species (ROS) production and nuclear factor kappa‐B (NF‐κB) phosphorylation; up‐regulated interleukin‐6 (IL‐6), tumour necrosis factor‐α (TNF‐α) and transforming growth factor‐β1 (TGF‐β1) levels in LA and EAT; decreased peroxisome proliferator‐activated receptor gamma (PPARγ) and adiponectin (APN) expression in EAT and was accompanied by atrial fibrosis and adipose infiltration. MET reversed these alterations. In vitro, lipopolysaccharide (LPS) exposure increased IL‐6, TNF‐α and TGF‐β1 expression and decreased PPARγ/APN expression in 3T3‐L1 adipocytes, which were all reversed after MET administration. Indirect coculture of HL‐1 cells with LPS‐stimulated 3T3‐L1 conditioned medium (CM) significantly increased IL‐6, TNF‐α and TGF‐β1 expression and decreased SERCA2a and p‐PLN expression, while LPS + MET CM and APN treatment alleviated the inflammatory response and sarcoplasmic reticulum Ca2+ handling dysfunction. MET attenuated the RAP‐induced increase in AF vulnerability, remodelling of atria and EAT adipokines production profiles. APN may play a key role in the prevention of AF‐dependent EAT remodelling and AF vulnerability by MET.
Collapse
Affiliation(s)
- Biao Li
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Sunny S Po
- Heart Rhythm Institute and Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Baojian Zhang
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China.,Department of Cardiology, the Affiliated Chinese Medicine Hospital of Xinjiang Medical University, Urumqi City, Xinjiang Province, China
| | - Fan Bai
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Jiayi Li
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Fen Qin
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Na Liu
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Chao Sun
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Yichao Xiao
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Tao Tu
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Shenghua Zhou
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| | - Qiming Liu
- Department of Cardiology/Cardiac Catheterization Lab, Second Xiangya Hospital, Central South University, Changsha City, Hunan Province, China
| |
Collapse
|
8
|
Pro-inflammatory macrophages coupled with glycolysis remodel adipose vasculature by producing platelet-derived growth factor-B in obesity. Sci Rep 2020; 10:670. [PMID: 31959796 PMCID: PMC6970998 DOI: 10.1038/s41598-019-57368-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Accepted: 12/30/2019] [Indexed: 01/23/2023] Open
Abstract
Adipose tissue macrophages (ATMs) play a central role in tissue remodeling and homeostasis. However, whether ATMs promote adipose angiogenesis in obesity remains unclear. We examined the impact of ATMs deletion on adipose angiogenesis and tissue expansion in the epididymal white adipose tissue (eWAT) of high-fat diet (HFD)-fed mice by using liposome-encapsulated clodronate. We further elucidated the induction mechanisms of platelet-derived growth factor (PDGF)-B in macrophages in response to obesity-associated metabolic stresses, since it plays a significant role in the regulation of pericyte behavior for the initiation of neoangiogenesis during tissue expansion. ATM depletion prevented adipose tissue expansion in HFD-fed mice by inhibiting pericyte detachment from vessels, resulting in less vasculature in eWAT. The lipopolysaccharide (LPS) stimulation and high glucose concentration augmented glucose incorporation and glycolytic capacity with the induction of Pdgfb mRNA. This effect was mediated through extracellular signal-regulated kinase (ERK) among mitogen-activated protein kinases coupled with glycolysis in RAW264.7 macrophages. The Pdgfb induction system was distinct from that of inflammatory cytokines mediated by mechanistic target of rapamycin complex 1 (mTORC1) and NFκB signaling. Thus, obesity-associated hyperglycemia and chronic inflammation fuels ERK signaling coupled with glycolysis in pro-inflammatory macrophages, which contribute to the expansion of eWAT through PDGF-B-dependent vascular remodeling.
Collapse
|
9
|
Fitzpatrick SF. Immunometabolism and Sepsis: A Role for HIF? Front Mol Biosci 2019; 6:85. [PMID: 31555665 PMCID: PMC6742688 DOI: 10.3389/fmolb.2019.00085] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Accepted: 08/26/2019] [Indexed: 12/14/2022] Open
Abstract
Metabolic reprogramming of innate immune cells occurs during both the hyperinflammatory and immunotolerant phases of sepsis. The hypoxia inducible factor (HIF) signaling pathway plays a vital role in regulating these metabolic changes. This review initially summarizes the HIF-driven changes in metabolic dynamics of innate immune cells in response to sepsis. The hyperinflammatory phase of sepsis is accompanied by a metabolic switch from oxidative phosphorylation to HIF-1α mediated glycolysis. Furthermore, HIF driven alterations in arginine metabolism also occur during this phase. This promotes sepsis pathophysiology and the development of clinical symptoms. These early metabolic changes are followed by a late immunotolerant phase, in which suppressed HIF signaling promotes a switch from aerobic glycolysis to fatty acid oxidation, with a subsequent anti-inflammatory response developing. Recently the molecular mechanisms controlling HIF activation during these early and late phases have begun to be elucidated. In the final part of this review the contribution of toll-like receptors, transcription factors, metabolic intermediates, kinases and reactive oxygen species, in governing the HIF-induced metabolic reprogramming of innate immune cells will be discussed. Importantly, understanding these regulatory mechanisms can lead to the development of novel diagnostic and therapeutic strategies targeting the HIF-dependent metabolic state of innate immune cells.
Collapse
Affiliation(s)
- Susan F Fitzpatrick
- School of Medicine and Medical Science, University College Dublin, Dublin, Ireland
| |
Collapse
|
10
|
Cerium Oxide Nanoparticles Regulate Insulin Sensitivity and Oxidative Markers in 3T3-L1 Adipocytes and C2C12 Myotubes. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:2695289. [PMID: 30863477 PMCID: PMC6378795 DOI: 10.1155/2019/2695289] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Revised: 10/05/2018] [Accepted: 12/12/2018] [Indexed: 12/28/2022]
Abstract
Insulin resistance is associated with oxidative stress, mitochondrial dysfunction, and a chronic low-grade inflammatory status. In this sense, cerium oxide nanoparticles (CeO2 NPs) are promising nanomaterials with antioxidant and anti-inflammatory properties. Thus, we aimed to evaluate the effect of CeO2 NPs in mouse 3T3-L1 adipocytes, RAW 264.7 macrophages, and C2C12 myotubes under control or proinflammatory conditions. Macrophages were treated with LPS, and both adipocytes and myotubes with conditioned medium (25% LPS-activated macrophages medium) to promote inflammation. CeO2 NPs showed a mean size of ≤25.3 nm (96.7%) and a zeta potential of 30.57 ± 0.58 mV, suitable for cell internalization. CeO2 NPs reduced extracellular reactive oxygen species (ROS) in adipocytes with inflammation while increased in myotubes with control medium. The CeO2 NPs increased mitochondrial content was observed in adipocytes under proinflammatory conditions. Furthermore, the expression of Adipoq and Il10 increased in adipocytes treated with CeO2 NPs. In myotubes, both Il1b and Adipoq were downregulated while Irs1 was upregulated. Overall, our results suggest that CeO2 NPs could potentially have an insulin-sensitizing effect specifically on adipose tissue and skeletal muscle. However, further research is needed to confirm these findings.
Collapse
|
11
|
Alí A, Boutjdir M, Aromolaran AS. Cardiolipotoxicity, Inflammation, and Arrhythmias: Role for Interleukin-6 Molecular Mechanisms. Front Physiol 2019; 9:1866. [PMID: 30666212 PMCID: PMC6330352 DOI: 10.3389/fphys.2018.01866] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 12/11/2018] [Indexed: 12/12/2022] Open
Abstract
Fatty acid infiltration of the myocardium, acquired in metabolic disorders (obesity, type-2 diabetes, insulin resistance, and hyperglycemia) is critically associated with the development of lipotoxic cardiomyopathy. According to a recent Presidential Advisory from the American Heart Association published in 2017, the current average dietary intake of saturated free-fatty acid (SFFA) in the US is 11–12%, which is significantly above the recommended <10%. Increased levels of circulating SFFAs (or lipotoxicity) may represent an unappreciated link that underlies increased vulnerability to cardiac dysfunction. Thus, an important objective is to identify novel targets that will inform pharmacological and genetic interventions for cardiomyopathies acquired through excessive consumption of diets rich in SFFAs. However, the molecular mechanisms involved are poorly understood. The increasing epidemic of metabolic disorders strongly implies an undeniable and critical need to further investigate SFFA mechanisms. A rapidly emerging and promising target for modulation by lipotoxicity is cytokine secretion and activation of pro-inflammatory signaling pathways. This objective can be advanced through fundamental mechanisms of cardiac electrical remodeling. In this review, we discuss cardiac ion channel modulation by SFFAs. We further highlight the contribution of downstream signaling pathways involving toll-like receptors and pathological increases in pro-inflammatory cytokines. Our expectation is that if we understand pathological remodeling of major cardiac ion channels from a perspective of lipotoxicity and inflammation, we may be able to develop safer and more effective therapies that will be beneficial to patients.
Collapse
Affiliation(s)
- Alessandra Alí
- Cardiovascular Research Program, VA New York Harbor Healthcare System, Brooklyn, NY, United States.,Department of Medicine, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Cell Biology, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Pharmacology, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Mohamed Boutjdir
- Cardiovascular Research Program, VA New York Harbor Healthcare System, Brooklyn, NY, United States.,Department of Medicine, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Cell Biology, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Pharmacology, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Medicine, New York University School of Medicine, New York, NY, United States
| | - Ademuyiwa S Aromolaran
- Cardiovascular Research Program, VA New York Harbor Healthcare System, Brooklyn, NY, United States.,Department of Medicine, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Cell Biology, State University of New York Downstate Medical Center, Brooklyn, NY, United States.,Department of Pharmacology, State University of New York Downstate Medical Center, Brooklyn, NY, United States
| |
Collapse
|