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Bondy SC. Mitochondrial Dysfunction as the Major Basis of Brain Aging. Biomolecules 2024; 14:402. [PMID: 38672420 PMCID: PMC11048299 DOI: 10.3390/biom14040402] [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: 02/19/2024] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/28/2024] Open
Abstract
The changes in the properties of three biological events that occur with cerebral aging are discussed. These adverse changes already begin to develop early in mid-life and gradually become more pronounced with senescence. Essentially, they are reflections of the progressive decline in effectiveness of key processes, resulting in the deviation of essential biochemical trajectories to ineffective and ultimately harmful variants of these programs. The emphasis of this review is the major role played by the mitochondria in the transition of these three important processes toward more deleterious variants as brain aging proceeds. The immune system: the shift away from an efficient immune response to a more unfocused, continuing inflammatory condition. Such a state is both ineffective and harmful. Reactive oxygen species are important intracellular signaling systems. Additionally, microglial phagocytic activity utilizing short lived reactive oxygen species contribute to the removal of aberrant or dead cells and bacteria. These processes are transformed into an excessive, untargeted, and persistent generation of pro-oxidant free radicals (oxidative stress). The normal efficient neural transmission is modified to a state of undirected, chronic low-level excitatory activity. Each of these changes is characterized by the occurrence of continuous activity that is inefficient and diffused. The signal/noise ratio of several critical biological events is thus reduced as beneficial responses are gradually replaced by their impaired and deleterious variants.
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Affiliation(s)
- Stephen C. Bondy
- Department of Environmental & Occupational Health, University of California, Irvine, CA 92697, USA;
- Department of Medicine, University of California, Irvine, CA 92697, USA
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Li J, Ruggiero-Ruff RE, He Y, Qiu X, Lainez N, Villa P, Godzik A, Coss D, Nair MG. Sexual dimorphism in obesity is governed by RELMα regulation of adipose macrophages and eosinophils. eLife 2023; 12:e86001. [PMID: 37162190 PMCID: PMC10171862 DOI: 10.7554/elife.86001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 04/18/2023] [Indexed: 05/11/2023] Open
Abstract
Obesity incidence is increasing worldwide with the urgent need to identify new therapeutics. Sex differences in immune cell activation drive obesity-mediated pathologies where males are more susceptible to obesity comorbidities and exacerbated inflammation. Here, we demonstrate that the macrophage-secreted protein RELMα critically protects females against high-fat diet (HFD)-induced obesity. Compared to male mice, serum RELMα levels were higher in both control and HFD-fed females and correlated with frequency of adipose macrophages and eosinophils. RELMα-deficient females gained more weight and had proinflammatory macrophage accumulation and eosinophil loss in the adipose stromal vascular fraction (SVF), while RELMα treatment or eosinophil transfer rescued this phenotype. Single-cell RNA-sequencing of the adipose SVF was performed and identified sex and RELMα-dependent changes. Genes involved in oxygen sensing and iron homeostasis, including hemoglobin and lncRNA Gm47283/Gm21887, correlated with increased obesity, while eosinophil chemotaxis and response to amyloid-beta were protective. Monocyte-to-macrophage transition was also dysregulated in RELMα-deficient animals. Collectively, these studies implicate a RELMα-macrophage-eosinophil axis in sex-specific protection against obesity and uncover new therapeutic targets for obesity.
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Affiliation(s)
- Jiang Li
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Rebecca E Ruggiero-Ruff
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Yuxin He
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Xinru Qiu
- Graduate Program in Genetics, Genomics and Bioinformatics, University of California RiversideRiversideUnited States
| | - Nancy Lainez
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Pedro Villa
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Adam Godzik
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Djurdjica Coss
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
| | - Meera G Nair
- Division of Biomedical Sciences, School of Medicine, University of California RiversideRiversideUnited States
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Li J, Ruggiero-Ruff RE, He Y, Qiu X, Lainez NM, Villa PA, Godzik A, Coss D, Nair MG. Sexual dimorphism in obesity is governed by RELMα regulation of adipose macrophages and eosinophils. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.13.523880. [PMID: 36711654 PMCID: PMC9882128 DOI: 10.1101/2023.01.13.523880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Obesity incidence is increasing worldwide with the urgent need to identify new therapeutics. Sex differences in immune cell activation drive obesity-mediated pathologies where males are more susceptible to obesity co-morbidities and exacerbated inflammation. Here, we demonstrate that the macrophage-secreted protein RELMα critically protects females against high fat diet-induced obesity. Compared to male mice, RELMα levels were elevated in both control and high fat dietfed females and correlated with adipose macrophages and eosinophils. RELMα-deficient females gained more weight and had pro-inflammatory macrophage accumulation and eosinophil loss, while both RELMα treatment and eosinophil transfer rescued this phenotype. Single cell RNA-sequencing of the adipose stromal vascular fraction was performed and identified sex and RELMα-dependent changes. Genes involved in oxygen sensing and iron homeostasis, including hemoglobin and lncRNA Gm47283, correlated with increased obesity, while eosinophil chemotaxis and response to amyloid-beta were protective. Monocyte-to-macrophage transition was also dysregulated in RELMα-deficient animals. Collectively, these studies implicate a RELMα-macrophage-eosinophil axis in sex-specific protection against obesity and uncover new therapeutic targets for obesity.
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Affiliation(s)
- Jiang Li
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Rebecca E Ruggiero-Ruff
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Yuxin He
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Xinru Qiu
- Graduate Program in Genetics, Genomics and Bioinformatics, University of California Riverside, Riverside, CA, USA
| | - Nancy M Lainez
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Pedro A Villa
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Adam Godzik
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Djurdjica Coss
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Meera G Nair
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
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Mechanism of Hypoxia-Mediated Smooth Muscle Cell Proliferation Leading to Vascular Remodeling. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3959845. [PMID: 36593773 PMCID: PMC9805398 DOI: 10.1155/2022/3959845] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 11/25/2022] [Accepted: 12/07/2022] [Indexed: 12/25/2022]
Abstract
Vascular remodeling refers to changes in the size, contraction, distribution, and flow rate of blood vessels and even changes in vascular function. Vascular remodeling can cause cardiovascular and cerebrovascular diseases. It can also lead to other systemic diseases, such as pulmonary hypertension, pulmonary atherosclerosis, chronic obstructive pulmonary disease, stroke, and ascites of broilers. Hypoxia is one of the main causes of vascular remodeling. Prolonged hypoxia or intermittent hypoxia can lead to loss of lung ventilation, causing respiratory depression, irregular respiratory rhythms, and central respiratory failure. Animals that are unable to adapt to the highland environment are also prone to sustained constriction of the small pulmonary arteries, increased resistance to pulmonary circulation, and impaired blood circulation, leading to pulmonary hypertension and right heart failure if they live in a highland environment for long periods of time. However, limited studies have been found on the relationship between hypoxia and vascular remodeling. Therefore, this review will explore the relationship between hypoxia and vascular remodeling from the aspects of endoplasmic reticulum stress, mitochondrial dysfunction, abnormal calcium channel, disordered cellular metabolism, abnormal expression of miRNA, and other factors. This will help to understand the detailed mechanism of hypoxia-mediated smooth muscle cell proliferation and vascular remodeling for the better treatment and management of diseases due to vascular remodeling.
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Aakerøy L, Cheng CW, Sustova P, Scrimgeour NR, Wahl SGF, Steinshamn S, Bowen TS, Brønstad E. Identification of exercise-regulated genes in mice exposed to cigarette smoke. Physiol Rep 2022; 10:e15505. [PMID: 36324300 PMCID: PMC9630761 DOI: 10.14814/phy2.15505] [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: 07/30/2022] [Revised: 10/13/2022] [Accepted: 10/18/2022] [Indexed: 11/06/2022] Open
Abstract
Cigarette smoke (CS) is the major risk factor for COPD and is linked to cardiopulmonary dysfunction. Exercise training as part of pulmonary rehabilitation is recommended for all COPD patients. It has several physiological benefits, but the mechanisms involved remain poorly defined. Here, we employed transcriptomic profiling and examined lung endothelium to investigate novel interactions between exercise and CS on cardiopulmonary alterations. Mice were exposed to 20 weeks of CS, CS + 6 weeks of high-intensity interval training on a treadmill, or control. Lung and cardiac (left and right ventricle) tissue were harvested and RNA-sequencing was performed and validated with RT-qPCR. Immunohistochemistry assessed pulmonary arteriolar changes. Transcriptome analysis between groups revealed 37 significantly regulated genes in the lung, 21 genes in the left ventricle, and 43 genes in the right ventricle (likelihood-ratio test). Validated genes that showed interaction between exercise and CS included angiotensinogen (p = 0.002) and resistin-like alpha (p = 0.019) in left ventricle, with prostacyclin synthetase different in pulmonary arterioles (p = 0.004). Transcriptomic profiling revealed changes in pulmonary and cardiac tissue following exposure to CS, with exercise training exerting rescue effects. Exercise-regulated genes included angiotensinogen and resistin-like alpha, however, it remains unclear if these represent potential candidate genes or biomarkers that could play a role during pulmonary rehabilitation.
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Affiliation(s)
- Lars Aakerøy
- Department of Thoracic MedicineSt. Olavs Hospital, Trondheim University HospitalTrondheimNorway
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health ScienceNorwegian University of Science and TechnologyTrondheimNorway
| | - Chew W. Cheng
- Leeds Institute of Cardiovascular and Metabolic MedicineUniversity of LeedsLeedsUK
| | - Pavla Sustova
- Department of PathologySt. Olav Hospital, Trondheim University HospitalTrondheimNorway
| | - Nathan R. Scrimgeour
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health ScienceNorwegian University of Science and TechnologyTrondheimNorway
| | | | - Sigurd Steinshamn
- Department of Thoracic MedicineSt. Olavs Hospital, Trondheim University HospitalTrondheimNorway
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health ScienceNorwegian University of Science and TechnologyTrondheimNorway
| | - T. Scott Bowen
- School of Biomedical Sciences, Faculty of Biological SciencesUniversity of LeedsLeedsUK
| | - Eivind Brønstad
- Department of Thoracic MedicineSt. Olavs Hospital, Trondheim University HospitalTrondheimNorway
- Department of Circulation and Medical Imaging, Faculty of Medicine and Health ScienceNorwegian University of Science and TechnologyTrondheimNorway
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Bonenfant J, Li J, Nasouf L, Miller J, Lowe T, Jaroszewski L, Qiu X, Thapamagar S, Mittal A, Godzik A, Klein W, Nair MG. Resistin Concentration in Early Sepsis and All-Cause Mortality at a Safety-Net Hospital in Riverside County. J Inflamm Res 2022; 15:3925-3940. [PMID: 35860230 PMCID: PMC9289958 DOI: 10.2147/jir.s370788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Accepted: 06/29/2022] [Indexed: 11/23/2022] Open
Abstract
Background Sepsis mortality has remained unchanged for greater than a decade, and early recognition continues to be the most important factor in mortality outcome. Plasma resistin concentration is increased in sepsis, but its mechanism and clinical relevance is unclear. As one function, resistin interacts with toll-like receptor 4 in competition with lipopolysaccharide, a main component of the gram-negative bacterial cell wall. It is not known if the type of infection leading to sepsis influences resistin production. The objective of this study was to investigate whether 1) early plasma resistin concentration can predict mortality, 2) elevated plasma resistin concentration is associated with clinical disease severity scores, such as SOFA, mSOFA and APACHE II, and 3) plasma resistin concentrations differ between gram negative versus other etiologies of sepsis. Methods This was an exploratory study in the framework of a prospective observational design. Peripheral venous blood samples were obtained from subjects admitted to the intensive care unit at clinical recognition of sepsis (0 hour) and at 6 and 24 hours. Vasopressor utilization was not a requirement for inclusion. Plasma was analyzed for resistin concentration by ELISA. Cytokine concentrations including IL-6, IL-8, and IL-10 were determined by cytokine bead array. Cytokine data were evaluated against publicly available sepsis RNA expression datasets to compare protein versus RNA expression levels in predicting clinical disease state. Clinical data were collected from electronic health records for clinical severity index calculations and context for interpretation of resistin and cytokine concentrations. Subjects were followed up to 60 days, or until death, whichever came first. Statistical analysis was completed with R package and SPSS software. Results Resistin levels were elevated in subjects admitted to the intensive care unit with sepsis. Four-hundred subjects were screened with 45 subjects included in the final analysis. Thirteen of 45 patients were non-survivors. Mortality within 60 days correlated with significantly higher resistin concentrations than in survivors. A resistin concentration of >126 ng/mL at clinical recognition of sepsis and >197 ng/mL within the first 24 hours were associated with mortality within 60 days with an area under the curve of 0.82 and 0.88, respectively. Most subjects with resistin concentration greater than these threshold values were deceased prior to 30 days. Resistin concentrations correlated with SOFA, mSOFA, and APACHE II scores in addition to having association with increases in inflammatory and sepsis biomarkers. These associations were validated with analysis of RNA expression datasets. Conclusion Plasma resistin concentrations of >126 ng/mL at clinical recognition of sepsis and >197 ng/mL within the first 24 hours of clinical sepsis recognition are associated with all-cause mortality. Resistin concentration within this timeframe also has comparable mortality association to well-validated clinical severity indices of SOFA, mSOFA, and APACHE II scores.
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Affiliation(s)
- Jeffrey Bonenfant
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA.,Division of Pulmonary, Critical Care, Hyperbaric, Allergy and Sleep Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Jiang Li
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Luqman Nasouf
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA
| | - Joseph Miller
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Tammy Lowe
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA
| | - Lukasz Jaroszewski
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Xinru Qiu
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Suman Thapamagar
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA.,Division of Pulmonary, Critical Care, Hyperbaric, Allergy and Sleep Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Aarti Mittal
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA.,Division of Pulmonary, Critical Care, Hyperbaric, Allergy and Sleep Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Adam Godzik
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
| | - Walter Klein
- Department of Medicine, Division of Pulmonary and Critical Care Medicine, Riverside University Health System Medical Center, Moreno Valley, CA, USA.,Division of Pulmonary, Critical Care, Hyperbaric, Allergy and Sleep Medicine, School of Medicine, Loma Linda University, Loma Linda, CA, USA
| | - Meera G Nair
- Division of Biomedical Sciences, School of Medicine, University of California Riverside, Riverside, CA, USA
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