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Jack BU, Dias S, Pheiffer C. Comparative Effects of Tumor Necrosis Factor Alpha, Lipopolysaccharide, and Palmitate on Mitochondrial Dysfunction in Cultured 3T3-L1 Adipocytes. Cell Biochem Biophys 2024:10.1007/s12013-024-01522-3. [PMID: 39269560 DOI: 10.1007/s12013-024-01522-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2024] [Indexed: 09/15/2024]
Abstract
We have previously reported that dysregulated lipid metabolism and inflammation in 3T3-L1 adipocytes is attributed to tumor necrosis factor alpha (TNFα) rather than lipopolysaccharide (LPS) and palmitate (PA). In this study, we further compared the modulative effects of TNFα, LPS, and PA on mitochondrial function by treating 3T3-L1 adipocytes with TNFα (10 ng/mL), LPS (100 ng/mL), and PA (0.75 mM) individually or in combination for 24 h. Results showed a significant reduction in intracellular adenosine triphosphate (ATP) content, mitochondrial bioenergetics, total antioxidant capacity, and the mRNA expression of citrate synthase (Cs), sirtuin 3 (Sirt3), protein kinase AMP-activated catalytic subunit alpha 2 (Prkaa2), peroxisome proliferator-activated receptor gamma coactivator 1 alpha (Ppargc1α), nuclear respiratory factor 1 (Nrf1), and superoxide dismutase 1 (Sod1) in cells treated with TNFα individually or in combination with LPS and PA. Additionally, TNFα treatments decreased insulin receptor substrate 1 (Irs1), insulin receptor substrate 2 (Irs2), solute carrier family 2, facilitated glucose transporter member 4 (Slc2a4), and phosphoinositide 3 kinase regulatory subunit 1 (Pik3r1) mRNA expression. Treatment with LPS and PA alone, or in combination, did not affect the assessed metabolic parameters, while the combination of LPS and PA increased lipid peroxidation. These results show that TNFα but not LPS and PA dysregulate mitochondrial function, thus inducing oxidative stress and impaired insulin signaling in 3T3-L1 adipocytes. This suggests that TNFα treatment can be used as a basic in vitro model for studying the pathophysiology of mitochondrial dysfunction and related metabolic complications and screening potential anti-obesity therapeutics in 3T3-L1 adipocytes.
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Affiliation(s)
- Babalwa Unice Jack
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, Cape Town, 7505, South Africa.
- Centre for Cardiometabolic Research in Africa, Division of Medical Physiology, Stellenbosch University, Tygerberg, Cape Town, 7505, South Africa.
| | - Stephanie Dias
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, Cape Town, 7505, South Africa
| | - Carmen Pheiffer
- Biomedical Research and Innovation Platform, South African Medical Research Council, Tygerberg, Cape Town, 7505, South Africa
- Department of Obstetrics and Gynaecology, Faculty of Health Sciences, University of Pretoria, Pretoria, 0001, South Africa
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2
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Wang R, Zhu Q, Huang H, Yang M, Wang X, Dong Y, Li Y, Guan Y, Zhong L, Niu Y. Periodic protein-restricted diets extend the lifespan of high-fat diet-induced Drosophila melanogaster males. Aging Cell 2024:e14327. [PMID: 39207121 DOI: 10.1111/acel.14327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 08/02/2024] [Accepted: 08/15/2024] [Indexed: 09/04/2024] Open
Abstract
Research has shown that sustained protein restriction can improve the effects of a high-fat diet on health and extend lifespan. However, long-term adherence to a protein-restricted diet is challenging. Therefore, we used a fly model to investigate whether periodic protein restriction (PPR) could also mitigate the potential adverse effects of a high-fat diet and extend healthy lifespan. Our study results showed that PPR reduced body weight, lipid levels, and oxidative stress induced by a high-fat diet in flies and significantly extended the healthy lifespan of male flies. Lipid metabolism and transcriptome results revealed that the common differences between the PPR group and the control group and high-fat group showed a significant decrease in palmitic acid in the PPR group; the enriched common differential pathways Toll and Imd were significantly inhibited in the PPR group. Further analysis indicated a significant positive correlation between palmitic acid levels and gene expression in the Toll and Imd pathways. This suggests that PPR effectively improves fruit fly lipid metabolism, reduces palmitic acid levels, and thereby suppresses the Toll and Imd pathways to extend the healthy lifespan of flies. Our study provides a theoretical basis for the long-term effects of PPR on health and offers a new dietary adjustment option for maintaining health in the long term.
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Affiliation(s)
- Ruohua Wang
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Qiushuang Zhu
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - He Huang
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Mengxia Yang
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Xinyue Wang
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yuanjie Dong
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yuqiao Li
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Yue Guan
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
| | - Lei Zhong
- Department of Breast Surgery, Sixth Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, China
| | - Yucun Niu
- Department of Nutrition and Food Hygiene, College of Public Health, Key Laboratory of Precision Nutrition and Health, Ministry of Education, Harbin Medical University, Harbin, Heilongjiang, China
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3
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Albornoz N, Álvarez-Indo J, de la Peña A, Arias-Muñoz E, Coca A, Segovia-Miranda F, Kerr B, Budini M, Criollo A, García-Robles MA, Morselli E, Soza A, Burgos PV. Targeting the immunoproteasome in hypothalamic neurons as a novel therapeutic strategy for high-fat diet-induced obesity and metabolic dysregulation. J Neuroinflammation 2024; 21:191. [PMID: 39095788 PMCID: PMC11297766 DOI: 10.1186/s12974-024-03154-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Accepted: 06/14/2024] [Indexed: 08/04/2024] Open
Abstract
OBJECTIVE Obesity represents a significant global health challenge characterized by chronic low-grade inflammation and metabolic dysregulation. The hypothalamus, a key regulator of energy homeostasis, is particularly susceptible to obesity's deleterious effects. This study investigated the role of the immunoproteasome, a specialized proteasomal complex implicated in inflammation and cellular homeostasis, during metabolic diseases. METHODS The levels of the immunoproteasome β5i subunit were analyzed by immunostaining, western blotting, and proteasome activity assay in mice fed with either a high-fat diet (HFD) or a regular diet (CHOW). We also characterized the impact of autophagy inhibition on the levels of the immunoproteasome β5i subunit and the activation of the AKT pathway. Finally, through confocal microscopy, we analyzed the contribution of β5i subunit inhibition on mitochondrial function by flow cytometry and mitophagy assay. RESULTS Using an HFD-fed obese mouse model, we found increased immunoproteasome levels in hypothalamic POMC neurons. Furthermore, we observed that palmitic acid (PA), a major component of saturated fats found in HFD, increased the levels of the β5i subunit of the immunoproteasome in hypothalamic neuronal cells. Notably, the increase in immunoproteasome expression was associated with decreased autophagy, a critical cellular process in maintaining homeostasis and suppressing inflammation. Functionally, PA disrupted the insulin-glucose axis, leading to reduced AKT phosphorylation and increased intracellular glucose levels in response to insulin due to the upregulation of the immunoproteasome. Mechanistically, we identified that the protein PTEN, a key regulator of insulin signaling, was reduced in an immunoproteasome-dependent manner. To further investigate the potential therapeutic implications of these findings, we used ONX-0914, a specific immunoproteasome inhibitor. We demonstrated that this inhibitor prevents PA-induced insulin-glucose axis imbalance. Given the interplay between mitochondrial dysfunction and metabolic disturbances, we explored the impact of ONX-0914 on mitochondrial function. Notably, ONX-0914 preserved mitochondrial membrane potential and attenuated mitochondrial ROS production in the presence of PA. Moreover, we found that ONX-0914 reduced mitophagy in the presence of PA. CONCLUSIONS Our findings strongly support the pathogenic involvement of the immunoproteasome in hypothalamic neurons in the context of HFD-induced obesity and metabolic disturbances. Targeting the immunoproteasome highlights a promising therapeutic strategy to mitigate the detrimental effects of obesity on the insulin-glucose axis and cellular homeostasis. This study provides valuable insights into the mechanisms driving obesity-related metabolic diseases and offers potential avenues for developing novel therapeutic interventions.
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Affiliation(s)
- Nicolás Albornoz
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Javiera Álvarez-Indo
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Adely de la Peña
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Eloisa Arias-Muñoz
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Alanis Coca
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Fabián Segovia-Miranda
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Bredford Kerr
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Mauricio Budini
- Laboratory of Molecular and Cellular Pathology, Institute in Dentistry Sciences, Dentistry Faculty, University of Chile, Santiago, Chile
| | - Alfredo Criollo
- Cell and Molecular Biology Laboratory, Institute in Dentistry Sciences, Dentistry Faculty, Universidad de Chile, Santiago, Chile
- Advanced Center for Chronic Diseases (ACCDiS), Faculty of Chemical and Pharmaceutical Sciences, Faculty of Medicine, Universidad de Chile, Santiago, Chile
| | - María A García-Robles
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Eugenia Morselli
- Department of Basic Sciences, Faculty of Medicine and Sciences, Universidad San Sebastián, Santiago, Chile
| | - Andrea Soza
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile.
- Centro Basal Ciencia & Vida, Universidad San Sebastián, Santiago, Chile.
| | - Patricia V Burgos
- Centro de Biología Celular y Biomedicina, Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile.
- Centro Basal Ciencia & Vida, Universidad San Sebastián, Santiago, Chile.
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Fernandes T, Melo T, Conde T, Neves B, Domingues P, Resende R, Pereira CF, Moreira PI, Domingues MR. Mapping the lipidome in mitochondria-associated membranes (MAMs) in an in vitro model of Alzheimer's disease. J Neurochem 2024; 168:1237-1253. [PMID: 38327008 DOI: 10.1111/jnc.16072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 12/06/2023] [Accepted: 01/24/2024] [Indexed: 02/09/2024]
Abstract
The disruption of mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) plays a relevant role in Alzheimer's disease (AD). MAMs have been implicated in neuronal dysfunction and death since it is associated with impairment of functions regulated in this subcellular domain, including lipid synthesis and trafficking, mitochondria dysfunction, ER stress-induced unfolded protein response (UPR), apoptosis, and inflammation. Since MAMs play an important role in lipid metabolism, in this study we characterized and investigated the lipidome alterations at MAMs in comparison with other subcellular fractions, namely microsomes and mitochondria, using an in vitro model of AD, namely the mouse neuroblastoma cell line (N2A) over-expressing the APP familial Swedish mutation (APPswe) and the respective control (WT) cells. Phospholipids (PLs) and fatty acids (FAs) were isolated from the different subcellular fractions and analyzed by HILIC-LC-MS/MS and GC-MS, respectively. In this in vitro AD model, we observed a down-regulation in relative abundance of some phosphatidylcholine (PC), lysophosphatidylcholine (LPC), and lysophosphatidylethanolamine (LPE) species with PUFA and few PC with saturated and long-chain FA. We also found an up-regulation of CL, and antioxidant alkyl acyl PL. Moreover, multivariate analysis indicated that each organelle has a specific lipid profile adaptation in N2A APPswe cells. In the FAs profile, we found an up-regulation of C16:0 in all subcellular fractions, a decrease of C18:0 levels in total fraction (TF) and microsomes fraction, and a down-regulation of 9-C18:1 was also found in mitochondria fraction in the AD model. Together, these results suggest that the over-expression of the familial APP Swedish mutation affects lipid homeostasis in MAMs and other subcellular fractions and supports the important role of lipids in AD physiopathology.
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Affiliation(s)
- Tânia Fernandes
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal
- IIIUC-Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
- CACC-Clinical Academic Center of Coimbra, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Tânia Melo
- Mass Spectrometry Centre, LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Tiago Conde
- Mass Spectrometry Centre, LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Bruna Neves
- Mass Spectrometry Centre, LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Pedro Domingues
- Mass Spectrometry Centre, LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Rosa Resende
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal
- IIIUC-Institute for Interdisciplinary Research, University of Coimbra, Coimbra, Portugal
- CACC-Clinical Academic Center of Coimbra, Coimbra, Portugal
| | - Cláudia F Pereira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal
- CACC-Clinical Academic Center of Coimbra, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Paula I Moreira
- CNC-Center for Neuroscience and Cell Biology, CIBB-Center for Innovative Biomedicine and Biotechnology, University of Coimbra, Coimbra, Portugal
- CACC-Clinical Academic Center of Coimbra, Coimbra, Portugal
- Faculty of Medicine, University of Coimbra, Coimbra, Portugal
| | - Maria Rosário Domingues
- Mass Spectrometry Centre, LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, Aveiro, Portugal
- CESAM - Centre for Environmental and Marine Studies, Department of Chemistry, University of Aveiro, Aveiro, Portugal
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5
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Lo CH, O’Connor LM, Loi GWZ, Saipuljumri EN, Indajang J, Lopes KM, Shirihai OS, Grinstaff MW, Zeng J. Acidic Nanoparticles Restore Lysosomal Acidification and Rescue Metabolic Dysfunction in Pancreatic β-Cells under Lipotoxic Conditions. ACS NANO 2024; 18:15452-15467. [PMID: 38830624 PMCID: PMC11192035 DOI: 10.1021/acsnano.3c09206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Revised: 05/09/2024] [Accepted: 05/16/2024] [Indexed: 06/05/2024]
Abstract
Type 2 diabetes (T2D), a prevalent metabolic disorder lacking effective treatments, is associated with lysosomal acidification dysfunction, as well as autophagic and mitochondrial impairments. Here, we report a series of biodegradable poly(butylene tetrafluorosuccinate-co-succinate) polyesters, comprising a 1,4-butanediol linker and varying ratios of tetrafluorosuccinic acid (TFSA) and succinic acid as components, to engineer lysosome-acidifying nanoparticles (NPs). The synthesized NPs are spherical with diameters of ≈100 nm and have low polydispersity and good stability. Notably, TFSA NPs, which are composed entirely of TFSA, exhibit the strongest degradation capability and superior acidifying properties. We further reveal significant downregulation of lysosomal vacuolar (H+)-ATPase subunits, which are responsible for maintaining lysosomal acidification, in human T2D pancreatic islets, INS-1 β-cells under chronic lipotoxic conditions, and pancreatic tissues of high-fat-diet (HFD) mice. Treatment with TFSA NPs restores lysosomal acidification, autophagic function, and mitochondrial activity, thereby improving the pancreatic function in INS-1 cells and HFD mice with lipid overload. Importantly, the administration of TFSA NPs to HFD mice reduces insulin resistance and improves glucose clearance. These findings highlight the therapeutic potential of lysosome-acidifying TFSA NPs for T2D.
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Affiliation(s)
- Chih Hung Lo
- Lee
Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
| | - Lance M. O’Connor
- College
of Biological Sciences, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Gavin Wen Zhao Loi
- Lee
Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
| | | | - Jonathan Indajang
- Meinig
School of Biomedical Engineering, Cornell
University, Ithaca, New York 14853, United States
| | - Kaitlynn M. Lopes
- Department
of Chemistry, Boston University, Boston, Massachusetts 02215, United States
| | - Orian S. Shirihai
- Division
of Endocrinology, Department of Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, California 90045, United States
- Department
of Molecular and Medical Pharmacology, University
of California, Los Angeles, Los
Angeles, California 90095, United States
| | - Mark W. Grinstaff
- Department
of Chemistry, Boston University, Boston, Massachusetts 02215, United States
- Department
of Biomedical Engineering, Boston University, Boston, Massachusetts 02215, United States
| | - Jialiu Zeng
- Lee
Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
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6
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Coates HW, Nguyen TB, Du X, Olzomer EM, Farrell R, Byrne FL, Yang H, Brown AJ. The constitutively active form of a key cholesterol synthesis enzyme is lipid droplet-localized and upregulated in endometrial cancer tissues. J Biol Chem 2024; 300:107232. [PMID: 38537696 PMCID: PMC11061744 DOI: 10.1016/j.jbc.2024.107232] [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: 02/29/2024] [Accepted: 03/18/2024] [Indexed: 04/26/2024] Open
Abstract
Cholesterol is essential for both normal cell viability and cancer cell proliferation. Aberrant activity of squalene monooxygenase (SM, also known as squalene epoxidase), the rate-limiting enzyme of the committed cholesterol synthesis pathway, is accordingly implicated in a growing list of cancers. We previously reported that hypoxia triggers the truncation of SM to a constitutively active form, thus preserving sterol synthesis during oxygen shortfalls. Here, we show SM truncation is upregulated and correlates with the magnitude of hypoxia in endometrial cancer tissues, supporting the in vivo relevance of our earlier work. To further investigate the pathophysiological consequences of SM truncation, we examined its lipid droplet-localized pool using complementary immunofluorescence and cell fractionation approaches and found that it exclusively comprises the truncated enzyme. This partitioning is facilitated by the loss of an endoplasmic reticulum-embedded region at the SM N terminus, whereas the catalytic domain containing membrane-associated C-terminal helices is spared. Moreover, we determined multiple amphipathic helices contribute to the lipid droplet localization of truncated SM. Taken together, our results expand on the striking differences between the two forms of SM and suggest upregulated truncation may contribute to SM-related oncogenesis.
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Affiliation(s)
- Hudson W Coates
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Tina B Nguyen
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Ximing Du
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Ellen M Olzomer
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Rhonda Farrell
- Chris O'Brien Lifehouse, Camperdown, New South Wales, Australia; Prince of Wales Private Hospital, Randwick, New South Wales, Australia
| | - Frances L Byrne
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Hongyuan Yang
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia
| | - Andrew J Brown
- School of Biotechnology and Biomolecular Sciences, UNSW, Sydney, New South Wales, Australia.
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7
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Van K, Burns JL, Monk JM. Effect of Short-Chain Fatty Acids on Inflammatory and Metabolic Function in an Obese Skeletal Muscle Cell Culture Model. Nutrients 2024; 16:500. [PMID: 38398822 PMCID: PMC10891728 DOI: 10.3390/nu16040500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 01/29/2024] [Accepted: 02/01/2024] [Indexed: 02/25/2024] Open
Abstract
The fermentation of non-digestible carbohydrates produces short-chain fatty acids (SCFAs), which have been shown to impact both skeletal muscle metabolic and inflammatory function; however, their effects within the obese skeletal muscle microenvironment are unknown. In this study, we developed a skeletal muscle in vitro model to mimic the critical features of the obese skeletal muscle microenvironment using L6 myotubes co-treated with 10 ng/mL lipopolysaccharide (LPS) and 500 µM palmitic acid (PA) for 24 h ± individual SCFAs, namely acetate, propionate and butyrate at 0.5 mM and 2.5 mM. At the lower SCFA concentration (0.5 mM), all three SCFA reduced the secreted protein level of RANTES, and only butyrate reduced IL-6 protein secretion and the intracellular protein levels of activated (i.e., ratio of phosphorylated-total) NFκB p65 and STAT3 (p < 0.05). Conversely, at the higher SCFA concentration (2.5 mM), individual SCFAs exerted different effects on inflammatory mediator secretion. Specifically, butyrate reduced IL-6, MCP-1 and RANTES secretion, propionate reduced IL-6 and RANTES, and acetate only reduced RANTES secretion (p < 0.05). All three SCFAs reduced intracellular protein levels of activated NFκB p65 and STAT3 (p < 0.05). Importantly, only the 2.5 mM SCFA concentration resulted in all three SCFAs increasing insulin-stimulated glucose uptake compared to control L6 myotube cultures (p < 0.05). Therefore, SCFAs exert differential effects on inflammatory mediator secretion in a cell culture model, recapitulating the obese skeletal muscle microenvironment; however, all three SCFAs exerted a beneficial metabolic effect only at a higher concentration via increasing insulin-stimulated glucose uptake, collectively exerting differing degrees of a beneficial effect on obesity-associated skeletal muscle dysfunction.
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Affiliation(s)
- Kelsey Van
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada;
| | - Jessie L. Burns
- Department of Health Sciences, Carleton University, Ottawa, ON K1S 5B6, Canada;
| | - Jennifer M. Monk
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, ON N1G 2W1, Canada;
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8
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Veluthakal R, Esparza D, Hoolachan JM, Balakrishnan R, Ahn M, Oh E, Jayasena CS, Thurmond DC. Mitochondrial Dysfunction, Oxidative Stress, and Inter-Organ Miscommunications in T2D Progression. Int J Mol Sci 2024; 25:1504. [PMID: 38338783 PMCID: PMC10855860 DOI: 10.3390/ijms25031504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 01/15/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024] Open
Abstract
Type 2 diabetes (T2D) is a heterogenous disease, and conventionally, peripheral insulin resistance (IR) was thought to precede islet β-cell dysfunction, promoting progression from prediabetes to T2D. New evidence suggests that T2D-lean individuals experience early β-cell dysfunction without significant IR. Regardless of the primary event (i.e., IR vs. β-cell dysfunction) that contributes to dysglycemia, significant early-onset oxidative damage and mitochondrial dysfunction in multiple metabolic tissues may be a driver of T2D onset and progression. Oxidative stress, defined as the generation of reactive oxygen species (ROS), is mediated by hyperglycemia alone or in combination with lipids. Physiological oxidative stress promotes inter-tissue communication, while pathological oxidative stress promotes inter-tissue mis-communication, and new evidence suggests that this is mediated via extracellular vesicles (EVs), including mitochondria containing EVs. Under metabolic-related stress conditions, EV-mediated cross-talk between β-cells and skeletal muscle likely trigger mitochondrial anomalies leading to prediabetes and T2D. This article reviews the underlying molecular mechanisms in ROS-related pathogenesis of prediabetes, including mitophagy and mitochondrial dynamics due to oxidative stress. Further, this review will describe the potential of various therapeutic avenues for attenuating oxidative damage, reversing prediabetes and preventing progression to T2D.
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Affiliation(s)
- Rajakrishnan Veluthakal
- Department of Molecular and Cellular Endocrinology, Arthur Riggs Diabetes & Metabolism Research Institute, City of Hope Beckman Research Institute, 1500 E. Duarte Rd, Duarte, CA 91010, USA; (D.E.); (J.M.H.); (R.B.); (M.A.); (E.O.); (C.S.J.)
| | | | | | | | | | | | | | - Debbie C. Thurmond
- Department of Molecular and Cellular Endocrinology, Arthur Riggs Diabetes & Metabolism Research Institute, City of Hope Beckman Research Institute, 1500 E. Duarte Rd, Duarte, CA 91010, USA; (D.E.); (J.M.H.); (R.B.); (M.A.); (E.O.); (C.S.J.)
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9
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Seliga AK, Zabłocki K, Bandorowicz-Pikuła J. Palmitate Stimulates Expression of the von Willebrand Factor and Modulates Toll-like Receptors Level and Activity in Human Umbilical Vein Endothelial Cells (HUVECs). Int J Mol Sci 2023; 25:254. [PMID: 38203423 PMCID: PMC10779284 DOI: 10.3390/ijms25010254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 01/12/2024] Open
Abstract
An increased concentration of palmitate in circulation is one of the most harmful factors in obesity. The von Willebrand factor (vWF), a protein involved in haemostasis, is produced and secreted by the vascular endothelium. An increased level of vWF in obese patients is associated with thrombosis and cardiovascular disease. The aim of this study was to investigate a palmitate effect on vWF in endothelial cells and understand the mechanisms of palmitate-activated signalling. Human umbilical vein endothelial cells (HUVECs) incubated in the presence of palmitate, exhibited an increased VWF gene expression, vWF protein maturation, and stimulated vWF secretion. Cardamonin, a Nuclear Factor kappa B (NF-κB) inhibitor, abolished the palmitate effect on VWF expression. The inhibition of Toll-like receptor (TLR) 2 with C29 resulted in the TLR4 overactivation in palmitate-treated cells. Palmitate, in the presence of TLR4 inhibitor TAK-242, leads to a higher expression of TLR6, CD36, and TIRAP. The silencing of TLR4 resulted in an increase in TLR2 level and vice versa. The obtained results indicate a potential mechanism of obesity-induced thrombotic complication caused by fatty acid activation of NF-κB signalling and vWF upregulation and help to identify various compensatory mechanisms related to TLR4 signal transduction.
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Affiliation(s)
| | | | - Joanna Bandorowicz-Pikuła
- Laboratory of Cellular Metabolism, Nencki Institute of Experimental Biology PAS, 3 Pasteur Str., 02-093 Warsaw, Poland; (A.K.S.); (K.Z.)
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10
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Moreira R, Martins AD, Ferreira R, Alves MG, Pereira MDL, Oliveira PF. Impact of Chromium Picolinate on Leydig Cell Steroidogenesis and Antioxidant Balance Using an In Vitro Insulin Resistance Model. Antioxidants (Basel) 2023; 13:40. [PMID: 38247463 PMCID: PMC10812815 DOI: 10.3390/antiox13010040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/20/2023] [Accepted: 12/21/2023] [Indexed: 01/23/2024] Open
Abstract
Leydig cells (LCs) play a pivotal role in male fertility, producing testosterone. Chromium (III) picolinate (CrPic3), a contentious supplement with antidiabetic and antioxidant properties, raises concerns regarding male fertility. Using a rodent LC line, we investigated the cytotoxicity of increasing CrPic3 doses. An insulin resistance (IR) model was established using palmitate (PA), and LCs were further exposed to CrPic3 to assess its antioxidant/antidiabetic activities. An exometabolome analysis was performed using 1H-NMR. Mitochondrial function and oxidative stress were evaluated via immunoblot. Steroidogenesis was assessed by quantifying androstenedione through ELISA. Our results uncover the toxic effects of CrPic3 on LCs even at low doses under IR conditions. Furthermore, even under these IR conditions, CrPic3 fails to enhance glucose consumption but restores the expression of mitochondrial complexes CII and CIII, alleviating oxidative stress in LCs. While baseline androgen production remained unaffected, CrPic3 promoted androstenedione production in LCs in the presence of PA, suggesting that it promotes cholesterol conversion into androgenic intermediates in this context. This study highlights the need for caution with CrPic3 even at lower doses. It provides valuable insights into the intricate factors influencing LCs metabolism and antioxidant defenses, shedding light on potential benefits and risks of CrPic3, particularly in IR conditions.
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Affiliation(s)
- Rúben Moreira
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (R.M.); (A.D.M.); (R.F.)
- LAQV-REQUIMTE, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Ana D. Martins
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (R.M.); (A.D.M.); (R.F.)
- LAQV-REQUIMTE, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Rita Ferreira
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (R.M.); (A.D.M.); (R.F.)
- LAQV-REQUIMTE, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Marco G. Alves
- iBiMED-Institute of Biomedicine, Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal;
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal;
- Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Pedro F. Oliveira
- Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal; (R.M.); (A.D.M.); (R.F.)
- LAQV-REQUIMTE, University of Aveiro, 3810-193 Aveiro, Portugal
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11
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Li C, Sun J, Zhang X, Zhou M, Gan X. Implications of MCU complex in metabolic diseases. FASEB J 2023; 37:e23046. [PMID: 37389546 DOI: 10.1096/fj.202300218r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 05/17/2023] [Accepted: 06/07/2023] [Indexed: 07/01/2023]
Abstract
Metabolic diseases are considered the primary culprit for physical and mental health of individuals. Although the diagnosis of these diseases is relatively easy, more effective and convenient potent drugs are still being explored. Ca2+ across the inner mitochondrial membrane is a vital intracellular messenger that regulates energy metabolism and cellular Ca2+ homeostasis and is involved in cell death. Mitochondria rely on a selective mitochondrial Ca2+ unidirectional transport complex (MCU complex) in their inner membrane for Ca2+ uptake. We found that the channel contains several subunits and undergoes dramatic transformations in various pathological processes, especially in metabolic diseases. In this way, we believe that the MCU complex becomes a target with significant potential for these diseases. However, there is no review linking the two factors, thus hindering the possibility of new drug production. Here, we highlight the connection between MCU complex-related Ca2+ transport and the pathophysiology of metabolic diseases, adding understanding and insight at the molecular level to provide new insights for targeting MCU to reverse metabolism-related diseases.
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Affiliation(s)
- Chen Li
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Jiyu Sun
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xidan Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Min Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
| | - Xueqi Gan
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, School of Chemical Engineering, Sichuan University, Chengdu, China
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12
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Loh CH, Kuo WW, Lin SZ, Shih CY, Lin PY, Situmorang JH, Huang CY. PKC-δ-dependent mitochondrial ROS attenuation is involved as 9-OAHSA combats lipoapotosis in rat hepatocytes induced by palmitic acid and in Syrian hamsters induced by high-fat high-cholesterol high-fructose diet. Toxicol Appl Pharmacol 2023; 470:116557. [PMID: 37207915 DOI: 10.1016/j.taap.2023.116557] [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: 04/07/2023] [Revised: 05/08/2023] [Accepted: 05/15/2023] [Indexed: 05/21/2023]
Abstract
Metabolic-associated fatty liver disease (MAFLD) is a global concern, often undetected until reaching an advanced stage. Palmitic acid (PA) is a type of fatty acid that increases and leads to liver apoptosis in MAFLD. However, there is currently no approved therapy or compound for MAFLD. Recently, branched fatty acid esters of hydroxy fatty acids (FAHFAs), a group of bioactive lipids, have emerged as promising agents to treat associated metabolic diseases. This study utilizes one type of FAHFA, oleic acid ester of 9-hydroxystearic acid (9-OAHSA), to treat PA-induced lipoapoptosis in an in vitro MAFLD model using rat hepatocytes and a high-fat high-cholesterol high-fructose (HFHCHFruc) diet in Syrian hamsters. The results indicate that 9-OAHSA rescues hepatocytes from PA-induced apoptosis and attenuates lipoapoptosis and dyslipidemia in Syrian hamsters. Additionally, 9-OAHSA decreases the generation of mitochondrial reactive oxygen species (mito-ROS) and stabilizes the mitochondrial membrane potential in hepatocytes. The study also demonstrates that the effect of 9-OAHSA on mito-ROS generation is at least partially mediated by PKC-δ signaling. These findings suggest that 9-OAHSA shows promise as a therapy for MAFLD.
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Affiliation(s)
- Ching-Hui Loh
- Department of Family Medicine and Medical Research, Buddhist Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan; Center for Aging and Health, Buddhist Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | - Wei-Wen Kuo
- Department of Biological Science and Technology, China Medical University, Taichung, Taiwan
| | - Shinn-Zong Lin
- Bioinnovation Center, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan; Department of Neurosurgery, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan
| | | | - Pi-Yu Lin
- Buddhist Compassion Relief Tzu Chi Foundation, Hualien, Taiwan
| | - Jiro Hasegawa Situmorang
- Cardiovascular and Mitochondrial Related Disease Research Center, Buddhist Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan; Center for Biomedical Research, National Research and Innovation Agency (BRIN), Cibinong, Indonesia.
| | - Chih-Yang Huang
- Cardiovascular and Mitochondrial Related Disease Research Center, Buddhist Tzu Chi General Hospital, Buddhist Tzu Chi Medical Foundation, Hualien, Taiwan; Graduate Institute of Biomedical Sciences, China Medical University, Taichung, Taiwan; Department of Medical Research, China Medical University Hospital, China Medical University, Taichung, Taiwan; Department of Biotechnology, Asia University, Taichung, Taiwan; Center of General Education, Buddhist Tzu Chi Medical Foundation, Tzu Chi University of Science and Technology, Hualien, Taiwan.
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13
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Lee J, Costa-Dookhan K, Panganiban K, MacKenzie N, Treen QC, Chintoh A, Remington G, Müller DJ, Sockalingam S, Gerretsen P, Sanches M, Karnovsky A, Stringer KA, Ellingrod VL, Tso IF, Taylor SF, Agarwal SM, Hahn MK, Ward KM. Metabolomic signatures associated with weight gain and psychosis spectrum diagnoses: A pilot study. Front Psychiatry 2023; 14:1169787. [PMID: 37168086 PMCID: PMC10164938 DOI: 10.3389/fpsyt.2023.1169787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 03/27/2023] [Indexed: 05/13/2023] Open
Abstract
Psychosis spectrum disorders (PSDs), as well as other severe mental illnesses where psychotic features may be present, like bipolar disorder, are associated with intrinsic metabolic abnormalities. Antipsychotics (APs), the cornerstone of treatment for PSDs, incur additional metabolic adversities including weight gain. Currently, major gaps exist in understanding psychosis illness biomarkers, as well as risk factors and mechanisms for AP-induced weight gain. Metabolomic profiles may identify biomarkers and provide insight into the mechanistic underpinnings of PSDs and antipsychotic-induced weight gain. In this 12-week prospective naturalistic study, we compared serum metabolomic profiles of 25 cases within approximately 1 week of starting an AP to 6 healthy controls at baseline to examine biomarkers of intrinsic metabolic dysfunction in PSDs. In 17 of the case participants with baseline and week 12 samples, we then examined changes in metabolomic profiles over 12 weeks of AP treatment to identify metabolites that may associate with AP-induced weight gain. In the cohort with pre-post data (n = 17), we also compared baseline metabolomes of participants who gained ≥5% baseline body weight to those who gained <5% to identify potential biomarkers of antipsychotic-induced weight gain. Minimally AP-exposed cases were distinguished from controls by six fatty acids when compared at baseline, namely reduced levels of palmitoleic acid, lauric acid, and heneicosylic acid, as well as elevated levels of behenic acid, arachidonic acid, and myristoleic acid (FDR < 0.05). Baseline levels of the fatty acid adrenic acid was increased in 11 individuals who experienced a clinically significant body weight gain (≥5%) following 12 weeks of AP exposure as compared to those who did not (FDR = 0.0408). Fatty acids may represent illness biomarkers of PSDs and early predictors of AP-induced weight gain. The findings may hold important clinical implications for early identification of individuals who could benefit from prevention strategies to reduce future cardiometabolic risk, and may lead to novel, targeted treatments to counteract metabolic dysfunction in PSDs.
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Affiliation(s)
- Jiwon Lee
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Kenya Costa-Dookhan
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Kristoffer Panganiban
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
| | - Nicole MacKenzie
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Quinn Casuccio Treen
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Araba Chintoh
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Gary Remington
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Daniel J. Müller
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada
- Pharmacogenetics Research Clinic, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Sanjeev Sockalingam
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Education, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Philip Gerretsen
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Geriatric Mental Health Services, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Marcos Sanches
- Biostatistics, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Alla Karnovsky
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Kathleen A. Stringer
- Department of Clinical Pharmacy, University of Michigan College of Pharmacy, Ann Arbor, MI, United States
| | - Vicki L. Ellingrod
- Department of Clinical Pharmacy, University of Michigan College of Pharmacy, Ann Arbor, MI, United States
- Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Ivy F. Tso
- Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United States
- Department of Psychiatry & Behavioral Health, Ohio State University, Columbus, OH, United States
| | - Stephan F. Taylor
- Department of Psychiatry, University of Michigan Medical School, Ann Arbor, MI, United States
| | - Sri Mahavir Agarwal
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Margaret K. Hahn
- Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Banting and Best Diabetes Centre, University of Toronto, Toronto, ON, Canada
| | - Kristen M. Ward
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI, United States
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14
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Sergi D, Sanz JM, Lazzer S, Brombo G, Zuliani G, Biolo G, Šimunič B, Pišot R, Dalla Nora E, Passaro A. Interleukin-18 Is a Potential Biomarker Linking Dietary Fatty Acid Quality and Insulin Resistance: Results from a Cross-Sectional Study in Northern Italy. Nutrients 2023; 15:nu15071782. [PMID: 37049621 PMCID: PMC10097292 DOI: 10.3390/nu15071782] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 03/27/2023] [Accepted: 03/30/2023] [Indexed: 04/08/2023] Open
Abstract
Dietary lipids are pivotal in modulating metabolic inflammation. Among the inflammatory mediators characterizing metabolic inflammation, interleukin 18 (IL-18) has been consistently associated with obesity and insulin resistance. This study aims to evaluate whether the quality of lipid intake impacts upon IL-18 plasma levels and the implications on insulin resistance computed by the homeostatic model assessment for insulin resistance (HOMA-IR). Using a cross-sectional design, this study confirmed that IL-18 correlated positively with insulin resistance and individuals with a HOMA-IR ≥ 2.5 displayed higher circulating IL-18 levels compared with their insulin-sensitive counterparts. In terms of the effect of the quality of dietary lipids on IL-18 circulating levels, the ratio between monounsaturated, omega-3, polyunsaturated and saturated fatty acids as well as the intake of eicosapentaenoic and docosahexaenoic acids correlated negatively with IL-18. Despite this, IL-18 circulating levels, but not dietary fatty acid quality, predicted insulin resistance. Nevertheless, the ratio between omega 3 and saturated fatty acids was a predictor of IL-18 plasma levels. Thus, the downregulation of IL-18 may underpin, at least partially, the beneficial metabolic effects of substituting omega 3 for saturated fatty acids with this cytokine potentially representing a biomarker linking dietary lipids and metabolic outcomes.
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Affiliation(s)
- Domenico Sergi
- Department of Translational Medicine, University of Ferrara, Via Luigi Borsari, 46, I-44121 Ferrara, Italy
| | - Juana Maria Sanz
- Department of Chemical and Pharmaceutical Sciences, University of Ferrara, Via Luigi Borsari, 46, I-44121 Ferrara, Italy
| | - Stefano Lazzer
- Department of Medicine, University of Udine, Piazzale M. Kolbe 4, I-33100 Udine, Italy
| | - Gloria Brombo
- Medical Department, University Hospital of Ferrara Arcispedale Sant’Anna, Via A. Moro 8, I-44124 Ferrara, Italy
| | - Giovanni Zuliani
- Department of Translational Medicine, University of Ferrara, Via Luigi Borsari, 46, I-44121 Ferrara, Italy
- Medical Department, University Hospital of Ferrara Arcispedale Sant’Anna, Via A. Moro 8, I-44124 Ferrara, Italy
| | - Gianni Biolo
- Department of Medicine, Surgery and Health Sciences, University of Trieste, Strada di Fiume, 447, I-34149 Trieste, Italy
| | - Boštjan Šimunič
- Institute for Kinesiology Research, Science and Research Centre of Koper, Garibaldijeva 1, SI-6000 Koper, Slovenia
| | - Rado Pišot
- Institute for Kinesiology Research, Science and Research Centre of Koper, Garibaldijeva 1, SI-6000 Koper, Slovenia
| | - Edoardo Dalla Nora
- Medical Department, University Hospital of Ferrara Arcispedale Sant’Anna, Via A. Moro 8, I-44124 Ferrara, Italy
| | - Angelina Passaro
- Department of Translational Medicine, University of Ferrara, Via Luigi Borsari, 46, I-44121 Ferrara, Italy
- Medical Department, University Hospital of Ferrara Arcispedale Sant’Anna, Via A. Moro 8, I-44124 Ferrara, Italy
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15
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Sergi D, Zauli E, Tisato V, Secchiero P, Zauli G, Cervellati C. Lipids at the Nexus between Cerebrovascular Disease and Vascular Dementia: The Impact of HDL-Cholesterol and Ceramides. Int J Mol Sci 2023; 24:ijms24054403. [PMID: 36901834 PMCID: PMC10002119 DOI: 10.3390/ijms24054403] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Cerebrovascular diseases and the subsequent brain hypoperfusion are at the basis of vascular dementia. Dyslipidemia, marked by an increase in circulating levels of triglycerides and LDL-cholesterol and a parallel decrease in HDL-cholesterol, in turn, is pivotal in promoting atherosclerosis which represents a common feature of cardiovascular and cerebrovascular diseases. In this regard, HDL-cholesterol has traditionally been considered as being protective from a cardiovascular and a cerebrovascular prospective. However, emerging evidence suggests that their quality and functionality play a more prominent role than their circulating levels in shaping cardiovascular health and possibly cognitive function. Furthermore, the quality of lipids embedded in circulating lipoproteins represents another key discriminant in modulating cardiovascular disease, with ceramides being proposed as a novel risk factor for atherosclerosis. This review highlights the role of HDL lipoprotein and ceramides in cerebrovascular diseases and the repercussion on vascular dementia. Additionally, the manuscript provides an up-to-date picture of the impact of saturated and omega-3 fatty acids on HDL circulating levels, functionality and ceramide metabolism.
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Affiliation(s)
- Domenico Sergi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
- Correspondence:
| | - Enrico Zauli
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Veronica Tisato
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
| | - Paola Secchiero
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
| | - Giorgio Zauli
- King Khaled Eye Specialistic Hospital, Riyadh 11462, Saudi Arabia
| | - Carlo Cervellati
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
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16
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Sergi D, Zauli E, Casciano F, Secchiero P, Zauli G, Fields M, Melloni E. Palmitic Acid Induced a Long-Lasting Lipotoxic Insult in Human Retinal Pigment Epithelial Cells, which Is Partially Counteracted by TRAIL. Antioxidants (Basel) 2022; 11:antiox11122340. [PMID: 36552548 PMCID: PMC9774631 DOI: 10.3390/antiox11122340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/15/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Hyperglycaemia and increased circulating saturated fatty acids are key metabolic features of type 2 diabetes mellitus (T2DM) that contribute to diabetic retinopathy pathogenesis. Contrarily, tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has been shown to improve or prevent T2DM. This study aimed at investigating the effect of TRAIL in an in vitro model of human retinal pigment epithelium: the ARPE-19 cell line, treated with palmitic acid (PA) in the presence of high glucose concentration. PA caused a drop in cellular metabolic activity and cell viability as well as an increase in apoptosis rates, which were paralleled by an upregulation of reactive oxygen species (ROS) generation as well as mitochondrial fragmentation. Despite ARPE-19 cells expressing TRAIL-R2 at the cell surface, TRAIL failed to counteract the cytotoxic effects of PA. However, when TRAIL was used alongside PA and then removed or used alone following PA challenge, it partially attenuated PA-induced lipotoxicity. This effect of TRAIL appeared to rely upon the modulation of inflammation and ROS production. Thus, TRAIL exerted a trophic effect on ARPE-19 cells, which became evident only when the lipotoxic insult was removed. Nevertheless, whether recombinant TRAIL might have a therapeutic potential for the treatment of diabetic retinopathy requires further investigation.
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Affiliation(s)
- Domenico Sergi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Enrico Zauli
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Fabio Casciano
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
- Interdepartmental Research Center for the Study of Multiple Sclerosis and Inflammatory and Degenerative Diseases of the Nervous System, University of Ferrara, 44121 Ferrara, Italy
- Correspondence:
| | - Paola Secchiero
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
| | - Giorgio Zauli
- King Khaled Eye Specialistic Hospital, Riyadh 11462, Saudi Arabia
| | - Matteo Fields
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy
| | - Elisabetta Melloni
- Department of Translational Medicine and LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
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17
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Guo Z, Wang Z, Liang R, Tian H, Chen X, Chen M. Reactive oxygen species activated by mitochondria-specific camptothecin prodrug for enhanced chemotherapy. Bosn J Basic Med Sci 2022; 22:934-948. [PMID: 35801419 PMCID: PMC9589304 DOI: 10.17305/bjbms.2022.7194] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/14/2022] [Indexed: 08/11/2023] Open
Abstract
Camptothecin (CPT) has attracted much attention due to its potent antitumor activities. However, the undesirable physicochemical properties, including poor water-solubility, unstable lactone ring and severe adverse effects limit its further application. In this study, two water-soluble prodrugs, CPT-lysine (CPTK) and CPT-arginine (CPTR), were designed and synthesized by conjugating lysine or arginine with CPT, improving its solubility, pharmacokinetic properties and tumor penetration. Importantly, the introduction of arginine into CPTR contributed to the mitochondria-specific delivery, which increased mitochondrial reactive oxygen species (ROS) generation, induced mitochondria dysfunction and enhanced cell apoptosis and in vivo anti-cancer effect. This strategy is believed to hold great potential for organelle-specific synergistic anti-tumor therapy.
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Affiliation(s)
- Zhaopei Guo
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
| | - Zian Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Ruifeng Liang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Huayu Tian
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
| | - Xuesi Chen
- Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, China
| | - Meiwan Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
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18
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Sheng CY, Son YH, Jang J, Park SJ. In vitro skeletal muscle models for type 2 diabetes. BIOPHYSICS REVIEWS 2022; 3:031306. [PMID: 36124295 PMCID: PMC9478902 DOI: 10.1063/5.0096420] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 08/18/2022] [Indexed: 06/15/2023]
Abstract
Type 2 diabetes mellitus, a metabolic disorder characterized by abnormally elevated blood sugar, poses a growing social, economic, and medical burden worldwide. The skeletal muscle is the largest metabolic organ responsible for glucose homeostasis in the body, and its inability to properly uptake sugar often precedes type 2 diabetes. Although exercise is known to have preventative and therapeutic effects on type 2 diabetes, the underlying mechanism of these beneficial effects is largely unknown. Animal studies have been conducted to better understand the pathophysiology of type 2 diabetes and the positive effects of exercise on type 2 diabetes. However, the complexity of in vivo systems and the inability of animal models to fully capture human type 2 diabetes genetics and pathophysiology are two major limitations in these animal studies. Fortunately, in vitro models capable of recapitulating human genetics and physiology provide promising avenues to overcome these obstacles. This review summarizes current in vitro type 2 diabetes models with focuses on the skeletal muscle, interorgan crosstalk, and exercise. We discuss diabetes, its pathophysiology, common in vitro type 2 diabetes skeletal muscle models, interorgan crosstalk type 2 diabetes models, exercise benefits on type 2 diabetes, and in vitro type 2 diabetes models with exercise.
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Affiliation(s)
- Christina Y. Sheng
- Biohybrid Systems Group, Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Young Hoon Son
- Biohybrid Systems Group, Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | | | - Sung-Jin Park
- Biohybrid Systems Group, Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University School of Medicine, Atlanta, Georgia 30322, USA
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19
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Martin JLA, Cartwright NM, Hutchinson AL, Robinson LE, Ma DWL, Monk JM. Differential Effects of Short-Chain Fatty Acids on L6 Myotube Inflammatory Mediator Production in Response to Lipopolysaccharide- or Palmitic Acid-Stimulation. Nutrients 2022; 14:nu14142826. [PMID: 35889783 PMCID: PMC9320465 DOI: 10.3390/nu14142826] [Citation(s) in RCA: 2] [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: 05/25/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 11/16/2022] Open
Abstract
Short-chain fatty acids (SCFA) produced from dietary non-digestible carbohydrate fermentation have metabolic effects in skeletal muscle; however, their effect on inflammatory mediator production is unknown. In this study, L6 myotubes were cultured with individual SCFA (acetate, propionate, and butyrate) at 0.5 mM and 2.5 mM ± 10 ng/mL lipopolysaccharide (LPS) or ± 500 µM palmitic acid (PA) for 24 h. In response to LPS, only butyrate had an effect at the lower concentration (0.5 mM), whereas at the higher concentration (2.5 mM) both propionate and butyrate reduced MCP-1, MIP-1α, and RANTES secretion (p < 0.05), and only butyrate reduced IL-6 secretion and intracellular protein levels of phospho-STAT3 (p < 0.05). In response to PA, 0.5 mM butyrate reduced protein expression of phospho-NFκB p65 and the secretion of IL-6, MIP-1α, and MCP-1, whereas all three SCFA reduced RANTES secretion (p < 0.05). At the 2.5 mM SCFA concentration combined with PA stimulation, all three SCFA reduced intracellular protein expression of phospho-NFκB p65 and phospho-STAT3 and secreted protein levels of MCP-1, IL-6, and RANTES, whereas only butyrate reduced secretion of MIP-1α (p < 0.05). Thus, SCFA exhibit differential effects on inflammatory mediator expression in response to LPS and PA stimulation, which has implications for their individual impacts on inflammation-mediated skeletal muscle dysfunction.
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Domínguez-López I, Arancibia-Riveros C, Casas R, Tresserra-Rimbau A, Razquin C, Martínez-González MÁ, Hu FB, Ros E, Fitó M, Estruch R, López-Sabater MC, Lamuela-Raventós RM. Changes in plasma total saturated fatty acids and palmitic acid are related to pro-inflammatory molecule IL-6 concentrations after nutritional intervention for one year. Biomed Pharmacother 2022; 150:113028. [PMID: 35483198 DOI: 10.1016/j.biopha.2022.113028] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 04/21/2022] [Accepted: 04/21/2022] [Indexed: 11/16/2022] Open
Abstract
Systemic inflammation is associated with an increased risk of non-communicable diseases, such as cardiovascular diseases and diabetes. Circulating fatty acids (FA) are known to be related to these conditions, possibly through their role in inflammation, although different types of FAs can have opposite effects on inflammatory mediators. The aim of the present study was to analyze the association of plasma FAs with inflammatory biomarkers in a PREDIMED trial subsample after one year of intervention. In a one-year longitudinal study of 91 participants of the PREDIMED trial (Barcelona-Clinic center), plasma FAs and inflammatory biomarkers were analyzed using gas chromatography and ELISA, respectively. In baseline plasma, a multivariable-adjusted ordinary least squares regression model showed that n-3 polyunsaturated FAs concentrations were inversely associated with concentrations of soluble intercellular adhesion molecule-1 (sICAM-1) and E-selectin, whereas the level of the most abundant saturated FA, palmitic acid, was directly associated with concentrations of interleukin-6 (IL-6) (β = 0.48 pg/mL, 95% CI: 0.03, 0.93 per 1-SD increase, p-value = 0.037). After one year of nutritional intervention, changes of plasma diet-derived total saturated FAs and palmitic acid were directly associated with changes in IL-6 (β = 0.59 pg/mL [95% CI: 0.28, 0.89] per 1-SD, p-value = 0.001; β = 0.64 pg/mL, 95% CI: 0.31, 0.98, p-value = 0.001), respectively, after correction for multiple testing. Our findings suggest that saturated FAs of dietary origin, especially palmitic acid, are directly involved in the increase of IL-6 in plasma.
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Affiliation(s)
- Inés Domínguez-López
- Department of Nutrition, Food Sciences and Gastronomy, XIA School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; INSA-UB, Nutrition and Food Safety Research Institute, University of Barcelona, 08921 Santa Coloma de Gramanet, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain.
| | - Camila Arancibia-Riveros
- Department of Nutrition, Food Sciences and Gastronomy, XIA School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; INSA-UB, Nutrition and Food Safety Research Institute, University of Barcelona, 08921 Santa Coloma de Gramanet, Spain.
| | - Rosa Casas
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Department of Internal Medicine, Hospital Clinic, Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain.
| | - Anna Tresserra-Rimbau
- Department of Nutrition, Food Sciences and Gastronomy, XIA School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; INSA-UB, Nutrition and Food Safety Research Institute, University of Barcelona, 08921 Santa Coloma de Gramanet, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain.
| | - Cristina Razquin
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Department of Preventive Medicine and Public Health, University of Navarra, IdiSNA, 31008 Pamplona, Spain.
| | - Miguel Á Martínez-González
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Department of Preventive Medicine and Public Health, University of Navarra, IdiSNA, 31008 Pamplona, Spain.
| | - Frank B Hu
- Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
| | - Emilio Ros
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Department of Endocrinology, Hospital Clinic, IDIBAPS, Barcelona, Spain.
| | - Montserrat Fitó
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Unit of Cardiovascular Risk and Nutrition, Institut Hospital del Mar de Investigaciones Médicas (IMIM), 08007 Barcelona, Spain.
| | - Ramon Estruch
- CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain; Department of Internal Medicine, Hospital Clinic, Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), University of Barcelona, Barcelona, Spain.
| | - M Carmen López-Sabater
- Department of Nutrition, Food Sciences and Gastronomy, XIA School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; INSA-UB, Nutrition and Food Safety Research Institute, University of Barcelona, 08921 Santa Coloma de Gramanet, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain.
| | - Rosa M Lamuela-Raventós
- Department of Nutrition, Food Sciences and Gastronomy, XIA School of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain; INSA-UB, Nutrition and Food Safety Research Institute, University of Barcelona, 08921 Santa Coloma de Gramanet, Spain; CIBER Fisiopatología de la Obesidad y Nutrición (CIBEROBN), Instituto de Salud Carlos III, 28029 Madrid, Spain.
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Rauen M, Hao D, Müller A, Mückter E, Bollheimer LC, Nourbakhsh M. Free Fatty Acid Species Differentially Modulate the Inflammatory Gene Response in Primary Human Skeletal Myoblasts. BIOLOGY 2021; 10:biology10121318. [PMID: 34943232 PMCID: PMC8698660 DOI: 10.3390/biology10121318] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 12/21/2022]
Abstract
Simple Summary Epidemiological studies show that obesity increases the risk of muscle mass loss with age, a syndrome called sarcopenic obesity. Obesity leads to increased free fatty acids (FFAs) and excessive fat deposits, which impair the integrity of skeletal muscles by unknown mechanisms. This report indicates that FFAs directly affect human skeletal muscle cell replication and inflammatory gene expression. The structural characteristics of FFAs play a decisive role in triggering both processes. Thus, the characterization of abundant FFA species in the skeletal muscle of obese individuals may become a useful tool to predict the progression of sarcopenic obesity. Abstract Age-related loss of skeletal muscle is associated with obesity and inflammation. In animal models, intramuscular fat deposits compromise muscle integrity; however, the relevant fat components that mediate muscular inflammation are not known. Previously, we hypothesized that free fatty acids (FFAs) may directly induce inflammatory gene expression in skeletal muscle cells of obese rats. Here, we examined this hypothesis in primary human skeletal myoblasts (SkMs) using multiplex expression analysis of 39 inflammatory proteins in response to different FFA species. Multiplex mRNA quantification confirmed that the IL6, IL1RA, IL4, LIF, CXCL8, CXCL1, CXCL12 and CCL2 genes were differentially regulated by saturated and unsaturated C16 or C18 FFAs. Fluorescence staining revealed that only saturated C16 and C18 strongly interfere with myoblast replication independent of desmin expression, mitochondrial abundance and oxidative activity. Furthermore, we addressed the possible implications of 71 human receptor tyrosine kinases (RTKs) in FFA-mediated effects. Phosphorylated EphB6 and TNK2 were associated with impaired myoblast replication by saturated C16 and C18 FFAs. Our data suggest that abundant FFA species in human skeletal muscle tissue may play a decisive role in the progression of sarcopenic obesity by affecting inflammatory signals or myoblast replication.
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