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Natarajan C, Le LHD, Gunasekaran M, Tracey KJ, Chernoff D, Levine YA. Electrical stimulation of the vagus nerve ameliorates inflammation and disease activity in a rat EAE model of multiple sclerosis. Proc Natl Acad Sci U S A 2024; 121:e2322577121. [PMID: 38968104 PMCID: PMC11252997 DOI: 10.1073/pnas.2322577121] [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: 12/21/2023] [Accepted: 05/31/2024] [Indexed: 07/07/2024] Open
Abstract
Multiple sclerosis (MS) is a demyelinating central nervous system (CNS) disorder that is associated with functional impairment and accruing disability. There are multiple U.S. Food and Drug Administration (FDA)-approved drugs that effectively dampen inflammation and slow disability progression. However, these agents do not work well for all patients and are associated with side effects that may limit their use. The vagus nerve (VN) provides a direct communication conduit between the CNS and the periphery, and modulation of the inflammatory reflex via electrical stimulation of the VN (VNS) shows efficacy in ameliorating pathology in several CNS and autoimmune disorders. We therefore investigated the impact of VNS in a rat experimental autoimmune encephalomyelitis (EAE) model of MS. In this study, VNS-mediated neuroimmune modulation is demonstrated to effectively decrease EAE disease severity and duration, infiltration of neutrophils and pathogenic lymphocytes, myelin damage, blood-brain barrier disruption, fibrinogen deposition, and proinflammatory microglial activation. VNS modulates expression of genes that are implicated in MS pathogenesis, as well as those encoding myelin proteins and transcription factors regulating new myelin synthesis. Together, these data indicate that neuroimmune modulation via VNS may be a promising approach to treat MS, that not only ameliorates symptoms but potentially also promotes myelin repair (remyelination).
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Affiliation(s)
| | | | | | - Kevin J. Tracey
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY11030
- Department of Neurosurgery, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY11549
- Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY11549
| | | | - Yaakov A. Levine
- SetPoint Medical, Valencia, CA91355
- Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY11549
- Division of Cardiovascular Medicine, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Solna, Stockholm171 76, Sweden
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Passaglia P, Kanashiro A, Batista Silva H, Carlos Carvalho Navegantes L, Lacchini R, Capellari Cárnio E, Branco LGS. Diminazene aceturate attenuates systemic inflammation via microbiota gut-5-HT brain-spleen sympathetic axis in male mice. Brain Behav Immun 2024; 119:105-119. [PMID: 38548186 DOI: 10.1016/j.bbi.2024.03.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 03/03/2024] [Accepted: 03/26/2024] [Indexed: 04/05/2024] Open
Abstract
The sympathetic arm of the inflammatory reflex is the efferent pathway through which the central nervous system (CNS) can control peripheral immune responses. Diminazene aceturate (DIZE) is an antiparasitic drug that has been reported to exert protective effects on various experimental models of inflammation. However, the pathways by which DIZE promotes a protective immunomodulatory effects still need to be well established, and no studies demonstrate the capacity of DIZE to modulate a neural reflex to control inflammation. C57BL/6 male mice received intraperitoneal administration of DIZE (2 mg/Kg) followed by lipopolysaccharide (LPS, 5 mg/Kg, i.p.). Endotoxemic animals showed hyperresponsiveness to inflammatory signals, while those treated with DIZE promoted the activation of the inflammatory reflex to attenuate the inflammatory response during endotoxemia. The unilateral cervical vagotomy did not affect the anti-inflammatory effect of DIZE in the spleen and serum. At the same time, splenic denervation attenuated tumor necrosis factor (TNF) synthesis in the spleen and serum. Using broad-spectrum antibiotics for two weeks showed that LPS modulated the microbiota to induce a pro-inflammatory profile in the intestine and reduced the serum concentration of tryptophan and serotonin (5-HT), while DIZE restored serum tryptophan and increased the hypothalamic 5-HT levels. Furthermore, the treatment with 4-Chloro-DL-phenylalanine (pcpa, an inhibitor of 5-HT synthesis) abolished the anti-inflammatory effects of the DIZE in the spleen. Our results indicate that DIZE promotes microbiota modulation to increase central 5-HT levels and activates the efferent sympathetic arm of the inflammatory reflex to control splenic TNF production in endotoxemic mice.
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Affiliation(s)
- Patrícia Passaglia
- Department of Oral and Basic Biology Ribeirão Preto, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil.
| | - Alexandre Kanashiro
- Department of Psychiatry and Behavioral Sciences, Translational Psychiatry Program, McGovern Medical School, The University of Texas Health Science Center at Houston (UTHealth), Houston, TX, USA
| | - Hadder Batista Silva
- Department of General Nursing, School of Nursing of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Riccardo Lacchini
- Department of Psychiatric Nursing and Human Sciences, School of Nursing of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Evelin Capellari Cárnio
- Department of General Nursing, School of Nursing of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Luiz G S Branco
- Department of Oral and Basic Biology Ribeirão Preto, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil; Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil.
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3
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Baek IS, Choi S, Yoon H, Chung G, Kim SK. Analgesic Effect of Auricular Vagus Nerve Stimulation on Oxaliplatin-induced Peripheral Neuropathic Pain in a Rodent Model. Exp Neurobiol 2024; 33:129-139. [PMID: 38993080 PMCID: PMC11247280 DOI: 10.5607/en24012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 07/13/2024] Open
Abstract
Cancer chemotherapy often triggers peripheral neuropathy in patients, leading to neuropathic pain in the extremities. While previous research has explored various nerve stimulation to alleviate chemotherapy-induced peripheral neuropathy (CIPN), evidence on the effectiveness of noninvasive auricular vagus nerve stimulation (aVNS) remains uncertain. This study aimed to investigate the efficacy of non-invasive aVNS in relieving CIPN pain. To induce CIPN in experimental animals, oxaliplatin was intraperitoneally administered to rats (6 mg/kg). Mechanical and cold allodynia, the representative symptoms of neuropathic pain, were evaluated using the von Frey test and acetone test, respectively. The CIPN animals were randomly assigned to groups and treated with aVNS (5 V, square wave) at different frequencies (2, 20, or 100 Hz) for 20 minutes. Results revealed that 20 Hz aVNS exhibited the most pronounced analgesic effect, while 2 or 100 Hz aVNS exhibited weak effects. Immunohistochemistry analysis demonstrated increased c-Fos expression in the locus coeruleus (LC) in the brain of CIPN rats treated with aVNS compared to sham treatment. To elucidate the analgesic mechanisms involving the adrenergic descending pathway, α1-, α2-, or β-adrenergic receptor antagonists were administered to the spinal cord before 20 Hz aVNS. Only the β-adrenergic receptor antagonist, propranolol, blocked the analgesic effect of aVNS. These findings suggest that 20 Hz aVNS may effectively alleviate CIPN pain through β-adrenergic receptor activation.
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Affiliation(s)
- In Seon Baek
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Seunghwan Choi
- Department of East-West Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
| | - Heera Yoon
- Division of Preclinical R&D, Neurogrin Inc., Seoul 02447, Korea
| | - Geehoon Chung
- Division of Preclinical R&D, Neurogrin Inc., Seoul 02447, Korea
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea
| | - Sun Kwang Kim
- Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
- Department of East-West Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul 02447, Korea
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4
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Li Y, Frederick RA, George D, Cogan SF, Pancrazio JJ, Bleris L, Hernandez-Reynoso AG. NeurostimML: a machine learning model for predicting neurostimulation-induced tissue damage. J Neural Eng 2024; 21:036054. [PMID: 38885676 DOI: 10.1088/1741-2552/ad593e] [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: 10/18/2023] [Accepted: 06/17/2024] [Indexed: 06/20/2024]
Abstract
Objective. The safe delivery of electrical current to neural tissue depends on many factors, yet previous methods for predicting tissue damage rely on only a few stimulation parameters. Here, we report the development of a machine learning approach that could lead to a more reliable method for predicting electrical stimulation-induced tissue damage by incorporating additional stimulation parameters.Approach. A literature search was conducted to build an initial database of tissue response information after electrical stimulation, categorized as either damaging or non-damaging. Subsequently, we used ordinal encoding and random forest for feature selection, and investigated four machine learning models for classification: Logistic Regression, K-nearest Neighbor, Random Forest, and Multilayer Perceptron. Finally, we compared the results of these models against the accuracy of the Shannon equation.Main Results. We compiled a database with 387 unique stimulation parameter combinations collected from 58 independent studies conducted over a period of 47 years, with 195 (51%) categorized as non-damaging and 190 (49%) categorized as damaging. The features selected for building our model with a Random Forest algorithm were: waveform shape, geometric surface area, pulse width, frequency, pulse amplitude, charge per phase, charge density, current density, duty cycle, daily stimulation duration, daily number of pulses delivered, and daily accumulated charge. The Shannon equation yielded an accuracy of 63.9% using akvalue of 1.79. In contrast, the Random Forest algorithm was able to robustly predict whether a set of stimulation parameters was classified as damaging or non-damaging with an accuracy of 88.3%.Significance. This novel Random Forest model can facilitate more informed decision making in the selection of neuromodulation parameters for both research studies and clinical practice. This study represents the first approach to use machine learning in the prediction of stimulation-induced neural tissue damage, and lays the groundwork for neurostimulation driven by machine learning models.
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Affiliation(s)
- Yi Li
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, United States of America
- Center for Systems Biology, The University of Texas at Dallas, Richardson, TX, United States of America
| | - Rebecca A Frederick
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR, United States of America
| | - Daniel George
- Department of Computer Science, The University of Texas at Dallas, Richardson, TX, United States of America
| | - Stuart F Cogan
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, United States of America
| | - Joseph J Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, United States of America
| | - Leonidas Bleris
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, United States of America
- Center for Systems Biology, The University of Texas at Dallas, Richardson, TX, United States of America
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, United States of America
| | - Ana G Hernandez-Reynoso
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, United States of America
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Cruz CJ, Yeater TD, Griffith JL, Allen KD. Vagotomy accelerates the onset of symptoms during early disease progression and worsens joint-level pathogenesis in a male rat model of chronic knee osteoarthritis. OSTEOARTHRITIS AND CARTILAGE OPEN 2024; 6:100467. [PMID: 38655014 PMCID: PMC11035058 DOI: 10.1016/j.ocarto.2024.100467] [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: 10/13/2023] [Accepted: 04/03/2024] [Indexed: 04/26/2024] Open
Abstract
Objective Low vagal tone is common in osteoarthritis (OA) comorbidities and results in greater peripheral inflammation. Characterizing vagal tone's role in OA pathogenesis may offer insights into OA's influences beyond the articular joint. We hypothesized that low vagal tone would accelerate onset of OA-related gait changes and worsen joint damage in a rat knee OA model. Methods Knee OA was induced in male Sprague Dawley rats by transecting the medial collateral ligament and medial meniscus. Then, left cervical vagus nerve transection (VGX, n = 9) or sham VGX (non-VGX, n = 6) was performed. Gait and tactile sensitivity were assessed at baseline and across 12 weeks, with histology and systemic inflammation evaluated at endpoint. Results At week 4, VGX animals showed limping gait characteristics through shifted stance times from their OA to non-OA limb (p = 0.055; stance time imbalance = 1.6 ± 1.6%) and shifted foot strike locations (p < 0.001; spatial symmetry = 48.4 ± 0.835%), while non-VGX animals walked with a balanced and symmetric gait. Also at week 4, while VGX animals had a mechanical sensitivity (50% withdrawal threshold) of 13.97 ± 7.70 compared to the non-VGX animal sensitivity of 29.74 ± 9.43, this difference was not statistically significant. Histologically, VGX animals showed thinner tibial cartilage and greater subchondral bone area than non-VGX animals (p = 0.076; VGX: 0.80 ± 0.036 mm2; non-VGX: 0.736 ± 0.066 mm2). No group differences in systemic inflammation were observed at endpoint. Conclusions VGX resulted in quicker onset of OA-related symptoms but remained unchanged at later timepoints. VGX also had thinner cartilage and abnormal bone remodeling than non-VGX. Overall, low vagal tone had mild effects on OA symptoms and joint remodeling, and not at the level seen in common OA comorbidities.
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Affiliation(s)
- Carlos J. Cruz
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA
| | - Taylor D. Yeater
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA
| | - Jacob L. Griffith
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA
| | - Kyle D. Allen
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, USA
- Department of Orthopaedic Surgery and Sports Medicine, College of Medicine, University of Florida, Gainesville, FL, USA
- Pain Research and Intervention Center of Excellence, University of Florida, Gainesville, FL, USA
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Kurata-Sato I, Mughrabi IT, Rana M, Gerber M, Al-Abed Y, Sherry B, Zanos S, Diamond B. Vagus nerve stimulation modulates distinct acetylcholine receptors on B cells and limits the germinal center response. SCIENCE ADVANCES 2024; 10:eadn3760. [PMID: 38669336 PMCID: PMC11051663 DOI: 10.1126/sciadv.adn3760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 03/26/2024] [Indexed: 04/28/2024]
Abstract
Acetylcholine is produced in the spleen in response to vagus nerve activation; however, the effects on antibody production have been largely unexplored. Here, we use a chronic vagus nerve stimulation (VNS) mouse model to study the effect of VNS on T-dependent B cell responses. We observed lower titers of high-affinity IgG and fewer antigen-specific germinal center (GC) B cells. GC B cells from chronic VNS mice exhibited altered mRNA and protein expression suggesting increased apoptosis and impaired plasma cell differentiation. Follicular dendritic cell (FDC) cluster dispersal and altered gene expression suggested poor function. The absence of acetylcholine-producing CD4+ T cells diminished these alterations. In vitro studies revealed that α7 and α9 nicotinic acetylcholine receptors (nAChRs) directly regulated B cell production of TNF, a cytokine crucial to FDC clustering. α4 nAChR inhibited coligation of CD19 to the B cell receptor, presumably decreasing B cell survival. Thus, VNS-induced GC impairment can be attributed to distinct effects of nAChRs on B cells.
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Affiliation(s)
- Izumi Kurata-Sato
- Center for Autoimmune Musculoskeletal and Hematopoietic Diseases, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Ibrahim T. Mughrabi
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Minakshi Rana
- Center for Autoimmune Musculoskeletal and Hematopoietic Diseases, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Michael Gerber
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Barbara Sherry
- Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Center for Immunology and Inflammation, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Manhasset, NY, USA
- Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA
| | - Betty Diamond
- Center for Autoimmune Musculoskeletal and Hematopoietic Diseases, The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
- Department of Molecular Medicine, Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
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Budhiraja A, Mehta A, Alhamo MA, Swedarsky R, Dahle S, Isseroff RR. Vagus nerve stimulation: Potential for treating chronic wounds. Wound Repair Regen 2024; 32:108-117. [PMID: 38235529 DOI: 10.1111/wrr.13151] [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: 07/23/2023] [Revised: 11/16/2023] [Accepted: 12/10/2023] [Indexed: 01/19/2024]
Abstract
Vagus nerve stimulation (VNS) has been approved as a treatment for various conditions, including drug-resistant epilepsy, migraines, chronic cluster headaches and treatment-resistant depression. It is known to have anti-inflammatory, anti-nociceptive and anti-adrenergic effects, and its therapeutic potential for diverse pathologies is being investigated. VNS can be achieved through invasive (iVNS) or non-invasive (niVNS) means, targeting different branches of the vagus nerve. iVNS devices require surgical implantation and have associated risks, while niVNS devices are generally better tolerated and have a better safety profile. Studies have shown that both iVNS and niVNS can reduce inflammation and pain perception in patients with acute and chronic conditions. VNS devices, such as the VNS Therapy System and MicroTransponder Vivistim, have received Food and Drug Administration approval for specific indications. Other niVNS devices, like NEMOS and gammaCore, have shown effectiveness in managing epilepsy, pain and migraines. VNS has also demonstrated potential in autoimmune disorders, such as rheumatoid arthritis and Crohn's disease, as well as neurological disorders like epilepsy and migraines. In addition, VNS has been explored in cardiovascular disorders, including post-operative atrial fibrillation and myocardial ischemia-reperfusion injury, and has shown positive outcomes. The mechanisms behind VNS's effects include the cholinergic anti-inflammatory pathway, modulation of cytokines and activation of specialised pro-resolving mediators. The modulation of inflammation by VNS presents a promising avenue for investigating its potential to improve the healing of chronic wounds. However, more research is needed to understand the specific mechanisms and optimise the use of VNS in wound healing. Ongoing clinical trials may support the use of this modality as an adjunct to improve healing.
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Affiliation(s)
- Anuj Budhiraja
- California Northstate University College of Medicine, Elk Grove, California, USA
| | - Alisha Mehta
- California Northstate University College of Medicine, Elk Grove, California, USA
| | - Moyasar A Alhamo
- Department of Dermatology, University of California, Davis, California, USA
| | | | - Sara Dahle
- Department of Dermatology, University of California, Davis, California, USA
- Podiatry Section, VA Northern California Health Care System, California, USA
| | - R Rivkah Isseroff
- Department of Dermatology, University of California, Davis, California, USA
- Dermatology Section, VA Northern California Health Care System, California, USA
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Marsili F, Potgieter P, Birkill CF. Adaptive Autonomic and Neuroplastic Control in Diabetic Neuropathy: A Narrative Review. Curr Diabetes Rev 2024; 20:38-54. [PMID: 38018186 DOI: 10.2174/0115733998253213231031050044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 08/31/2023] [Accepted: 09/28/2023] [Indexed: 11/30/2023]
Abstract
BACKGROUND Type 2 diabetes mellitus (T2DM) is a worldwide socioeconomic burden, and is accompanied by a variety of metabolic disorders, as well as nerve dysfunction referred to as diabetic neuropathy (DN). Despite a tremendous body of research, the pathogenesis of DN remains largely elusive. Currently, two schools of thought exist regarding the pathogenesis of diabetic neuropathy: a) mitochondrial-induced toxicity, and b) microvascular damage. Both mechanisms signify DN as an intractable disease and, as a consequence, therapeutic approaches treat symptoms with limited efficacy and risk of side effects. OBJECTIVE Here, we propose that the human body exclusively employs mechanisms of adaptation to protect itself during an adverse event. For this purpose, two control systems are defined, namely the autonomic and the neural control systems. The autonomic control system responds via inflammatory and immune responses, while the neural control system regulates neural signaling, via plastic adaptation. Both systems are proposed to regulate a network of temporal and causative connections which unravel the complex nature of diabetic complications. RESULTS A significant result of this approach infers that both systems make DN reversible, thus opening the door to novel therapeutic applications.
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Affiliation(s)
| | - Paul Potgieter
- Research Department, Algiamed Technologies, Burnaby, Canada
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Li Y, Frederick RA, George D, Cogan SF, Pancrazio JJ, Bleris L, Hernandez-Reynoso AG. NeurostimML: A machine learning model for predicting neurostimulation-induced tissue damage. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.18.562980. [PMID: 37905012 PMCID: PMC10614958 DOI: 10.1101/2023.10.18.562980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Objective The safe delivery of electrical current to neural tissue depends on many factors, yet previous methods for predicting tissue damage rely on only a few stimulation parameters. Here, we report the development of a machine learning approach that could lead to a more reliable method for predicting electrical stimulation-induced tissue damage by incorporating additional stimulation parameters. Approach A literature search was conducted to build an initial database of tissue response information after electrical stimulation, categorized as either damaging or non-damaging. Subsequently, we used ordinal encoding and random forest for feature selection, and investigated four machine learning models for classification: Logistic Regression, K-nearest Neighbor, Random Forest, and Multilayer Perceptron. Finally, we compared the results of these models against the accuracy of the Shannon equation. Main Results We compiled a database with 387 unique stimulation parameter combinations collected from 58 independent studies conducted over a period of 47 years, with 195 (51%) categorized as non-damaging and 190 (49%) categorized as damaging. The features selected for building our model with a Random Forest algorithm were: waveform shape, geometric surface area, pulse width, frequency, pulse amplitude, charge per phase, charge density, current density, duty cycle, daily stimulation duration, daily number of pulses delivered, and daily accumulated charge. The Shannon equation yielded an accuracy of 63.9% using a k value of 1.79. In contrast, the Random Forest algorithm was able to robustly predict whether a set of stimulation parameters was classified as damaging or non-damaging with an accuracy of 88.3%. Significance This novel Random Forest model can facilitate more informed decision making in the selection of neuromodulation parameters for both research studies and clinical practice. This study represents the first approach to use machine learning in the prediction of stimulation-induced neural tissue damage, and lays the groundwork for neurostimulation driven by machine learning models.
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Affiliation(s)
- Yi Li
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
- Center for Systems Biology, The University of Texas at Dallas, Richardson, TX, USA
| | - Rebecca A. Frederick
- Phil and Penny Knight Campus for Accelerating Scientific Impact, University of Oregon, Eugene, OR, USA
| | - Daniel George
- Department of Computer Science, The University of Texas at Dallas, Richardson, TX, USA
| | - Stuart F. Cogan
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Joseph J. Pancrazio
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Leonidas Bleris
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
- Center for Systems Biology, The University of Texas at Dallas, Richardson, TX, USA
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX, USA
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10
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Mughrabi IT, Gerber M, Jayaprakash N, Palandira SP, Al-Abed Y, Datta-Chaudhuri T, Smith C, Pavlov VA, Zanos S. Voltammetry in the spleen assesses real-time immunomodulatory norepinephrine release elicited by autonomic neurostimulation. J Neuroinflammation 2023; 20:236. [PMID: 37848937 PMCID: PMC10583388 DOI: 10.1186/s12974-023-02902-x] [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: 03/30/2023] [Accepted: 09/22/2023] [Indexed: 10/19/2023] Open
Abstract
BACKGROUND The noradrenergic innervation of the spleen is implicated in the autonomic control of inflammation and has been the target of neurostimulation therapies for inflammatory diseases. However, there is no real-time marker of its successful activation, which hinders the development of anti-inflammatory neurostimulation therapies and mechanistic studies in anti-inflammatory neural circuits. METHODS In mice, we performed fast-scan cyclic voltammetry (FSCV) in the spleen during intravenous injections of norepinephrine (NE), and during stimulation of the vagus, splanchnic, or splenic nerves. We defined the stimulus-elicited charge generated at the oxidation potential for NE (~ 0.88 V) as the "NE voltammetry signal" and quantified the dependence of the signal on NE dose and intensity of neurostimulation. We correlated the NE voltammetry signal with the anti-inflammatory effect of splenic nerve stimulation (SpNS) in a model of lipopolysaccharide- (LPS) induced endotoxemia, quantified as suppression of TNF release. RESULTS The NE voltammetry signal is proportional to the estimated peak NE blood concentration, with 0.1 μg/mL detection threshold. In response to SpNS, the signal increases within seconds, returns to baseline minutes later, and is blocked by interventions that deplete NE or inhibit NE release. The signal is elicited by efferent, but not afferent, electrical or optogenetic vagus nerve stimulation, and by splanchnic nerve stimulation. The magnitude of the signal during SpNS is inversely correlated with subsequent TNF suppression in endotoxemia and explains 40% of the variance in TNF measurements. CONCLUSIONS FSCV in the spleen provides a marker for real-time monitoring of anti-inflammatory activation of the splenic innervation during autonomic stimulation.
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Affiliation(s)
- Ibrahim T Mughrabi
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Michael Gerber
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Donald & Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Naveen Jayaprakash
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Santhoshi P Palandira
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Donald & Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Donald & Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Corey Smith
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH, USA
| | - Valentin A Pavlov
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Donald & Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Manhasset, NY, USA.
- Donald & Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA.
- Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA.
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11
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Kobori N, Moore AN, Redell JB, Dash PK. Caudal DMN neurons innervate the spleen and release CART peptide to regulate neuroimmune function. J Neuroinflammation 2023; 20:158. [PMID: 37403174 PMCID: PMC10318820 DOI: 10.1186/s12974-023-02838-2] [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: 05/04/2023] [Accepted: 06/19/2023] [Indexed: 07/06/2023] Open
Abstract
BACKGROUND Inflammation is a fundamental biological response to injury and infection, which if unregulated can contribute to the pathophysiology of many diseases. The vagus nerve, which primarily originates from the dorsal motor nucleus (DMN), plays an important role in rapidly dampening inflammation by regulating splenic function. However, direct vagal innervation of the spleen, which houses the majority of immune and inflammatory cells, has not been established. As an alternative to direct innervation, an anti-inflammatory reflex pathway has been proposed which involves the vagus nerve, the sympathetic celiac ganglion, and the neurotransmitter norepinephrine. Although sympathetic regulation of inflammation has been shown, the interaction of the vagus nerve and the celiac ganglia requires a unique interaction of parasympathetic and sympathetic inputs, making this putative mechanism of brain-spleen interaction controversial. BODY: As neuropeptides can be expressed at relatively high levels in neurons, we reasoned that DMN neuropeptide immunoreactivity could be used to determine their target innervation. Employing immunohistochemistry, subdiaphragmatic vagotomy, viral tract tracing, CRISPR-mediated knock-down, and functional assays, we show that cocaine and amphetamine-regulated transcript (CART) peptide-expressing projection neurons in the caudal DMN directly innervate the spleen. In response to lipopolysaccharide (LPS) stimulation, CART acts to reduce inflammation, an effect that can be augmented by intrasplenic administration of a synthetic CART peptide. These in vivo effects could be recapitulated in cultured splenocytes, suggesting that these cells express the as yet unidentified CART receptor(s). CONCLUSION Our results provide evidence for direct connections between the caudal DMN and spleen. In addition to acetylcholine, these neurons express the neuropeptide CART that, once released, acts to suppress inflammation by acting directly upon splenocytes.
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Affiliation(s)
- Nobuhide Kobori
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Anthony N Moore
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - John B Redell
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA
| | - Pramod K Dash
- Department of Neurobiology and Anatomy, The University of Texas McGovern Medical School, P.O. Box 20708, Houston, TX, 77225, USA.
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12
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Falvey A, Palandira SP, Chavan SS, Brines M, Tracey KJ, Pavlov VA. Electrical stimulation of the dorsal motor nucleus of the vagus regulates inflammation without affecting the heart rate. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.17.541191. [PMID: 37292846 PMCID: PMC10245723 DOI: 10.1101/2023.05.17.541191] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Background The vagus nerve plays an important role in neuroimmune interactions and in the regulation of inflammation. A major source of efferent vagus nerve fibers that contribute to the regulation of inflammation is the brainstem dorsal motor nucleus of the vagus (DMN) as recently shown using optogenetics. In contrast to optogenetics, electrical neuromodulation has broad therapeutic implications, but the anti-inflammatory efficacy of electrical DMN stimulation (eDMNS) was not previously investigated. Here, we examined the effects of eDMNS on heart rate (HR) and cytokine levels in murine endotoxemia as well as the cecal ligation and puncture (CLP) model of sepsis. Methods Anesthetized male 8-10-week-old C57BL/6 mice on a stereotaxic frame were subjected to eDMNS using a concentric bipolar electrode inserted into the left or right DMN or sham stimulation. eDMNS (50, 250 or 500 μA and 30 Hz, for 1 min) was performed and HR recorded. In endotoxemia experiments, sham or eDMNS utilizing 250 μA or 50 μA was performed for 5 mins and was followed by LPS (0.5 mg/kg) i.p. administration. eDMNS was also applied in mice with cervical unilateral vagotomy or sham operation. In CLP experiments sham or left eDMNS was performed immediately post CLP. Cytokines and corticosterone were analyzed 90 mins after LPS administration or 24h after CLP. CLP survival was monitored for 14 days. Results Either left or right eDMNS at 250 μA and 500 μA decreased HR, compared with pre- and post-stimulation. This effect was not observed at 50 μA. Left side eDMNS at 50 μA, compared with sham stimulation, significantly decreased serum and splenic levels of the pro-inflammatory cytokine TNF and increased serum levels of the anti-inflammatory cytokine IL-10 during endotoxemia. The anti-inflammatory effect of eDMNS was abrogated in mice with unilateral vagotomy and were not associated with serum corticosterone alterations. Right side eDMNS suppressed serum TNF levels but had no effects on serum IL-10 and on splenic cytokines. In mice with CLP, left side eDMNS suppressed serum TNF and IL-6, as well as splenic IL-6 and increased splenic IL-10 and significantly improved the survival rate of CLP mice. Conclusions For the first time we show that a regimen of eDMNS which does not cause bradycardia alleviates LPS-induced inflammation and these effects require an intact vagus nerve and are not associated with corticosteroid alterations. eDMNS also decreases inflammation and improves survival in a model of polymicrobial sepsis. These findings are of interest for further studies exploring bioelectronic anti-inflammatory approaches targeting the brainstem DMN.
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Affiliation(s)
- Aidan Falvey
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
| | - Santhoshi P. Palandira
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
- Elmezzi Graduate School of Molecular Medicine, 350 Community Drive, Manhasset, NY 11030, USA
| | - Sangeeta S. Chavan
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra University, Hempstead, New York 11549, USA
- Elmezzi Graduate School of Molecular Medicine, 350 Community Drive, Manhasset, NY 11030, USA
| | - Michael Brines
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
| | - Kevin J. Tracey
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra University, Hempstead, New York 11549, USA
- Elmezzi Graduate School of Molecular Medicine, 350 Community Drive, Manhasset, NY 11030, USA
| | - Valentin A. Pavlov
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY 11030, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra University, Hempstead, New York 11549, USA
- Elmezzi Graduate School of Molecular Medicine, 350 Community Drive, Manhasset, NY 11030, USA
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13
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Govindappa PK, Begom M, Gupta Y, Elfar JC, Rawat M, Elfar W. A critical role for erythropoietin on vagus nerve Schwann cells in intestinal motility. BMC Biotechnol 2023; 23:12. [PMID: 37127673 PMCID: PMC10152589 DOI: 10.1186/s12896-023-00781-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 03/30/2023] [Indexed: 05/03/2023] Open
Abstract
BACKGROUND Dysmotility and postoperative ileus (POI) are frequent major clinical problems post-abdominal surgery. Erythropoietin (EPO) is a multifunctional tissue-protective cytokine that promotes recovery of the intestine in various injury models. While EPO receptors (EPOR) are present in vagal Schwann cells, the role of EPOR in POI recovery is unknown because of the lack of EPOR antagonists or Schwann-cell specific EPOR knockout animals. This study was designed to explore the effect of EPO via EPOR in vagal nerve Schwann cells in a mouse model of POI. RESULTS The structural features of EPOR and its activation by EPO-mediated dimerization were understood using structural analysis. Later, using the Cre-loxP system, we developed a myelin protein zero (Mpz) promoter-driven knockout mouse model of Schwann cell EPOR (MpzCre-EPORflox/flox / Mpz-EPOR-KO) confirmed using PCR and qRT-PCR techniques. We then measured the intestinal transit time (ITT) at baseline and after induction of POI with and without EPO treatment. Although we have previously shown that EPO accelerates functional recovery in POI in wild type mice, EPO treatment did not improve functional recovery of ITT in POI of Mpz-EPOR-KO mice. CONCLUSIONS To the best of our knowledge, this is the first pre-clinical study to demonstrate a novel mouse model of EPOR specific knock out on Schwan cells with an effect in the gut. We also showed novel beneficial effects of EPO through vagus nerve Schwann cell-EPOR in intestinal dysmotility. Our findings suggest that EPO-EPOR signaling in the vagus nerve after POI is important for the functional recovery of ITT.
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Affiliation(s)
- Prem Kumar Govindappa
- Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA
| | - Mosammat Begom
- Department of Medicine, The Penn State University College of Medicine, Hershey, PA, 17033, USA
| | - Yash Gupta
- Department of Medicine, The Penn State University College of Medicine, Hershey, PA, 17033, USA
| | - John C Elfar
- Department of Orthopaedics and Sports Medicine, University of Arizona College of Medicine, Tucson, AZ, 85724, USA
| | - Manmeet Rawat
- Department of Medicine, The Penn State University College of Medicine, Hershey, PA, 17033, USA.
| | - Walaa Elfar
- Department of Pediatrics, University of Arizona College of Medicine, Tucson, AZ, 85724, USA.
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14
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Ahmed O, Caravaca AS, Crespo M, Dai W, Liu T, Guo Q, Leiva M, Sabio G, Shavva VS, Malin SG, Olofsson PS. Hepatic stellate cell activation markers are regulated by the vagus nerve in systemic inflammation. Bioelectron Med 2023; 9:6. [PMID: 36997988 PMCID: PMC10064698 DOI: 10.1186/s42234-023-00108-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 03/10/2023] [Indexed: 04/01/2023] Open
Abstract
BACKGROUND The liver is an important immunological organ and liver inflammation is part of the pathophysiology of non-alcoholic steatohepatitis, a condition that may promote cirrhosis, liver cancer, liver failure, and cardiovascular disease. Despite dense innervation of the liver parenchyma, little is known about neural regulation of liver function in inflammation. Here, we study vagus nerve control of the liver response to acute inflammation. METHODS Male C57BL/6 J mice were subjected to either sham surgery, surgical vagotomy, or electrical vagus nerve stimulation followed by intraperitoneal injection of the TLR2 agonist zymosan. Animals were euthanized and tissues collected 12 h after injection. Samples were analyzed by qPCR, RNAseq, flow cytometry, or ELISA. RESULTS Hepatic mRNA levels of pro-inflammatory mediators Ccl2, Il-1β, and Tnf-α were significantly higher in vagotomized mice compared with mice subjected to sham surgery. Differences in liver Ccl2 levels between treatment groups were largely reflected in the plasma chemokine (C-C motif) ligand 2 (CCL2) concentration. In line with this, we observed a higher number of macrophages in the livers of vagotomized mice compared with sham as measured by flow cytometry. In mice subjected to electrical vagus nerve stimulation, hepatic mRNA levels of Ccl2, Il1β, and Tnf-α, and plasma CCL2 levels, were significantly lower compared with sham. Interestingly, RNAseq revealed that a key activation marker for hepatic stellate cells (HSC), Pnpla3, was the most significantly differentially expressed gene between vagotomized and sham mice. Of note, several HSC-activation associated transcripts were higher in vagotomized mice, suggesting that signals in the vagus nerve contribute to HSC activation. In support of this, we observed significantly higher number of activated HSCs in vagotomized mice as compared with sham as measured by flow cytometry. CONCLUSIONS Signals in the cervical vagus nerve controlled hepatic inflammation and markers of HSC activation in zymosan-induced peritonitis.
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Affiliation(s)
- Osman Ahmed
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Biochemistry, Faculty of Medicine, Khartoum University, Khartoum, Sudan
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - April S Caravaca
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Maria Crespo
- Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain
| | - Wanmin Dai
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Ting Liu
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Qi Guo
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Magdalena Leiva
- Department of Immunology, School of Medicine, Complutense University of Madrid, Madrid, Spain
| | - Guadalupe Sabio
- Spanish National Center for Cardiovascular Research (CNIC), Madrid, Spain
| | - Vladimir S Shavva
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden
| | - Stephen G Malin
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Peder S Olofsson
- Department of Medicine Solna, Laboratory of Immunobiology, Division of Cardiovascular Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.
- Department of Medicine Solna, Stockholm Center for Bioelectronic Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA.
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15
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The Potential of Flavonoids and Flavonoid Metabolites in the Treatment of Neurodegenerative Pathology in Disorders of Cognitive Decline. Antioxidants (Basel) 2023; 12:antiox12030663. [PMID: 36978911 PMCID: PMC10045397 DOI: 10.3390/antiox12030663] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/23/2023] [Accepted: 03/01/2023] [Indexed: 03/11/2023] Open
Abstract
Flavonoids are a biodiverse family of dietary compounds that have antioxidant, anti-inflammatory, antiviral, and antibacterial cell protective profiles. They have received considerable attention as potential therapeutic agents in biomedicine and have been widely used in traditional complimentary medicine for generations. Such complimentary medical herbal formulations are extremely complex mixtures of many pharmacologically active compounds that provide a therapeutic outcome through a network pharmacological effects of considerable complexity. Methods are emerging to determine the active components used in complimentary medicine and their therapeutic targets and to decipher the complexities of how network pharmacology provides such therapeutic effects. The gut microbiome has important roles to play in the generation of bioactive flavonoid metabolites retaining or exceeding the antioxidative and anti-inflammatory properties of the intact flavonoid and, in some cases, new antitumor and antineurodegenerative bioactivities. Certain food items have been identified with high prebiotic profiles suggesting that neutraceutical supplementation may be beneficially employed to preserve a healthy population of bacterial symbiont species and minimize the establishment of harmful pathogenic organisms. Gut health is an important consideration effecting the overall health and wellbeing of linked organ systems. Bioconversion of dietary flavonoid components in the gut generates therapeutic metabolites that can also be transported by the vagus nerve and systemic circulation to brain cell populations to exert a beneficial effect. This is particularly important in a number of neurological disorders (autism, bipolar disorder, AD, PD) characterized by effects on moods, resulting in depression and anxiety, impaired motor function, and long-term cognitive decline. Native flavonoids have many beneficial properties in the alleviation of inflammation in tissues, however, concerns have been raised that therapeutic levels of flavonoids may not be achieved, thus allowing them to display optimal therapeutic effects. Dietary manipulation and vagal stimulation have both yielded beneficial responses in the treatment of autism spectrum disorders, depression, and anxiety, establishing the vagal nerve as a route of communication in the gut-brain axis with established roles in disease intervention. While a number of native flavonoids are beneficial in the treatment of neurological disorders and are known to penetrate the blood–brain barrier, microbiome-generated flavonoid metabolites (e.g., protocatechuic acid, urolithins, γ-valerolactones), which retain the antioxidant and anti-inflammatory potency of the native flavonoid in addition to bioactive properties that promote mitochondrial health and cerebrovascular microcapillary function, should also be considered as potential biotherapeutic agents. Studies are warranted to experimentally examine the efficacy of flavonoid metabolites directly, as they emerge as novel therapeutic options.
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16
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Harikesh PC, Yang CY, Wu HY, Zhang S, Donahue MJ, Caravaca AS, Huang JD, Olofsson PS, Berggren M, Tu D, Fabiano S. Ion-tunable antiambipolarity in mixed ion-electron conducting polymers enables biorealistic organic electrochemical neurons. NATURE MATERIALS 2023; 22:242-248. [PMID: 36635590 PMCID: PMC9894750 DOI: 10.1038/s41563-022-01450-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 11/28/2022] [Indexed: 05/29/2023]
Abstract
Biointegrated neuromorphic hardware holds promise for new protocols to record/regulate signalling in biological systems. Making such artificial neural circuits successful requires minimal device/circuit complexity and ion-based operating mechanisms akin to those found in biology. Artificial spiking neurons, based on silicon-based complementary metal-oxide semiconductors or negative differential resistance device circuits, can emulate several neural features but are complicated to fabricate, not biocompatible and lack ion-/chemical-based modulation features. Here we report a biorealistic conductance-based organic electrochemical neuron (c-OECN) using a mixed ion-electron conducting ladder-type polymer with stable ion-tunable antiambipolarity. The latter is used to emulate the activation/inactivation of sodium channels and delayed activation of potassium channels of biological neurons. These c-OECNs can spike at bioplausible frequencies nearing 100 Hz, emulate most critical biological neural features, demonstrate stochastic spiking and enable neurotransmitter-/amino acid-/ion-based spiking modulation, which is then used to stimulate biological nerves in vivo. These combined features are impossible to achieve using previous technologies.
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Affiliation(s)
- Padinhare Cholakkal Harikesh
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - Chi-Yuan Yang
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - Han-Yan Wu
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - Silan Zhang
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
- Wallenberg Wood Science Center, Linköping University, Norrköping, Sweden
| | - Mary J Donahue
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - April S Caravaca
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Jun-Da Huang
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - Peder S Olofsson
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden
| | - Magnus Berggren
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
- Wallenberg Wood Science Center, Linköping University, Norrköping, Sweden
- n-Ink AB, Norrköping, Sweden
| | - Deyu Tu
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden
| | - Simone Fabiano
- Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, Norrköping, Sweden.
- Wallenberg Wood Science Center, Linköping University, Norrköping, Sweden.
- n-Ink AB, Norrköping, Sweden.
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17
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Neuromodulation as a Potential Disease-Modifying Therapy for Osteoarthritis. Curr Rheumatol Rep 2023; 25:1-11. [PMID: 36435890 DOI: 10.1007/s11926-022-01094-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2022] [Indexed: 11/28/2022]
Abstract
PURPOSE OF REVIEW The following review discusses the therapeutic potential of targeting the autonomic nervous system (ANS) for osteoarthritis (OA) treatment and encourages the field to consider the candidacy of bioelectronic medicine as a novel OA treatment strategy. RECENT FINDINGS The study of OA pathogenesis has focused on changes occurring at the joint level. As such, treatments for OA have been aimed at the local joint environment, intending to resolve local inflammation and decrease pain. However, OA pathogenesis has shown to be more than joint wear and tear. Specifically, OA-related peripheral and central sensitization can prompt neuroplastic changes in the nervous system beyond the articular joint. These neuroplastic changes may alter physiologic systems, like the neuroimmune axis. In this way, OA and related comorbidities may share roots in the form of altered neuroimmune communication and autonomic dysfunction. ANS modulation may be able to modify OA pathogenesis or reduce the impact of OA comorbidities. Moreover, blocking chronic nociceptive drive from the joint may help to prevent maladaptive nervous system plasticity in OA.
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Prathumsap N, Ongnok B, Khuanjing T, Arinno A, Maneechote C, Apaijai N, Chunchai T, Arunsak B, Kerdphoo S, Janjek S, Chattipakorn SC, Chattipakorn N. Vagus nerve stimulation exerts cardioprotection against doxorubicin-induced cardiotoxicity through inhibition of programmed cell death pathways. Cell Mol Life Sci 2022; 80:21. [PMID: 36583785 PMCID: PMC11072695 DOI: 10.1007/s00018-022-04678-4] [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: 09/25/2022] [Revised: 12/07/2022] [Accepted: 12/21/2022] [Indexed: 12/31/2022]
Abstract
The aberration of programmed cell death including cell death associated with autophagy/mitophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis can be observed in the development and progression of doxorubicin-induced cardiotoxicity (DIC). Vagus nerve stimulation (VNS) has been shown to exert cardioprotection against cardiomyocyte death through the release of the neurotransmitter acetylcholine (ACh) under a variety of pathological conditions. However, the roles of VNS and its underlying mechanisms against DIC have never been investigated. Forty adults male Wistar rats were divided into 5 experimental groups: (i) control without VNS (CSham) group, (ii) doxorubicin (3 mg/kg/day, i.p.) without VNS (DSham) group, (iii) doxorubicin + VNS (DVNS) group, (iv) doxorubicin + VNS + mAChR antagonist (atropine; 1 mg/kg/day, ip, DVNS + Atro) group, and (v) doxorubicin + VNS + nAChR antagonist (mecamylamine; 7.5 mg/kg/day, ip, DVNS + Mec) group. Our results showed that doxorubicin insult led to left ventricular (LV) dysfunction through impaired cardiac autonomic balance, decreased mitochondrial function, imbalanced mitochondrial dynamics, and exacerbated cardiomyocyte death including autophagy/mitophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis. However, VNS treatment improved cardiac mitochondrial and autonomic functions, and suppressed excessive autophagy, apoptosis, necroptosis, pyroptosis, and ferroptosis, leading to improved LV function. Consistent with this, ACh effectively improved cell viability and suppressed cell cytotoxicity in doxorubicin-treated H9c2 cells. In contrast, either inhibitors of muscarinic (mAChR) or nicotinic acetylcholine receptor (nAChR) completely abrogated the favorable effects mediated by VNS and acetylcholine. These findings suggest that VNS exerts cardioprotective effects against doxorubicin-induced cardiomyocyte death via activation of both mAChR and nAChR.
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Affiliation(s)
- Nanthip Prathumsap
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Benjamin Ongnok
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Thawatchai Khuanjing
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Apiwan Arinno
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Chayodom Maneechote
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Nattayaporn Apaijai
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Titikorn Chunchai
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Busarin Arunsak
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Sasiwan Kerdphoo
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Sornram Janjek
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Siriporn C Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand
- Department of Oral Biology and Diagnostic Science, Faculty of Dentistry, Chiang Mai University, Chiang Mai, 50200, Thailand
| | - Nipon Chattipakorn
- Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand.
- Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand.
- Center of Excellence in Cardiac Electrophysiology, Chiang Mai University, Chiang Mai, 50200, Thailand.
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19
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Martinez S, Veirano F, Constandinou TG, Silveira F. Trends in volumetric-energy efficiency of implantable neurostimulators: a review from a circuits and systems perspective. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2022; PP:2-20. [PMID: 37015536 DOI: 10.1109/tbcas.2022.3228895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
This paper presents a comprehensive review of state-of-the-art, commercially available neurostimulators. We analyse key design parameters and performance metrics of 45 implantable medical devices across six neural target categories: deep brain, vagus nerve, spinal cord, phrenic nerve, sacral nerve and hypoglossal nerve. We then benchmark these alongside modern cardiac pacemaker devices that represent a more established market. This work studies trends in device size, electrode number, battery technology (i.e., primary and secondary use and chemistry), power consumption and longevity. This information is analysed to show the course of design decisions adopted by industry and identifying opportunity for further innovation. We identify fundamental limits in power consumption, longevity and size as well as the interdependencies and trade-offs. We propose a figure of merit to quantify volumetric efficiency within specific therapeutic targets, battery technologies/capacities, charging capabilities and electrode count. Finally, we compare commercially available implantable medical devices with recently developed systems in the research community. We envisage this analysis to aid circuit and system designers in system optimisation and identifying innovation opportunities, particularly those related to low power circuit design techniques.
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20
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Donahue MJ, Ejneby MS, Jakešová M, Caravaca AS, Andersson G, Sahalianov I, Đerek V, Hult H, Olofsson PS, Głowacki ED. Wireless optoelectronic devices for vagus nerve stimulation in mice. J Neural Eng 2022; 19. [PMID: 36356313 DOI: 10.1088/1741-2552/aca1e3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 11/10/2022] [Indexed: 11/12/2022]
Abstract
Objective.Vagus nerve stimulation (VNS) is a promising approach for the treatment of a wide variety of debilitating conditions, including autoimmune diseases and intractable epilepsy. Much remains to be learned about the molecular mechanisms involved in vagus nerve regulation of organ function. Despite an abundance of well-characterized rodent models of common chronic diseases, currently available technologies are rarely suitable for the required long-term experiments in freely moving animals, particularly experimental mice. Due to challenging anatomical limitations, many relevant experiments require miniaturized, less invasive, and wireless devices for precise stimulation of the vagus nerve and other peripheral nerves of interest. Our objective is to outline possible solutions to this problem by using nongenetic light-based stimulation.Approach.We describe how to design and benchmark new microstimulation devices that are based on transcutaneous photovoltaic stimulation. The approach is to use wired multielectrode cuffs to test different stimulation patterns, and then build photovoltaic stimulators to generate the most optimal patterns. We validate stimulation through heart rate analysis.Main results.A range of different stimulation geometries are explored with large differences in performance. Two types of photovoltaic devices are fabricated to deliver stimulation: photocapacitors and photovoltaic flags. The former is simple and more compact, but has limited efficiency. The photovoltaic flag approach is more elaborate, but highly efficient. Both can be used for wireless actuation of the vagus nerve using light impulses.Significance.These approaches can enable studies in small animals that were previously challenging, such as long-termin vivostudies for mapping functional vagus nerve innervation. This new knowledge may have potential to support clinical translation of VNS for treatment of select inflammatory and neurologic diseases.
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Affiliation(s)
- Mary J Donahue
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, SE-60174 Norrköping, Sweden
| | - Malin Silverå Ejneby
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, SE-60174 Norrköping, Sweden.,Wallenberg Centre for Molecular Medicine, Linköping University, SE-58185 Linköping, Sweden
| | - Marie Jakešová
- Bioelectronics Materials and Devices Laboratory, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
| | - April S Caravaca
- Laboratory of Immunobiology, Center for Bioelectronic Medicine, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, Sweden
| | | | - Ihor Sahalianov
- Bioelectronics Materials and Devices Laboratory, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
| | - Vedran Đerek
- Department of Physics, Faculty of Science, University of Zagreb, Bijenička c. 32, 10000 Zagreb, Croatia
| | - Henrik Hult
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, Sweden.,Department of Mathematics, KTH, 11428 Stockholm, Sweden
| | - Peder S Olofsson
- Laboratory of Immunobiology, Center for Bioelectronic Medicine, Department of Medicine, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, Sweden.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, United States of America
| | - Eric Daniel Głowacki
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, SE-60174 Norrköping, Sweden.,Bioelectronics Materials and Devices Laboratory, Central European Institute of Technology, Brno University of Technology, Purkyňova 123, 61200 Brno, Czech Republic
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21
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Barlow B, Ponnaluri S, Barlow A, Roth W. Targeting the gut microbiome in the management of sepsis-associated encephalopathy. Front Neurol 2022; 13:999035. [PMID: 36247756 PMCID: PMC9557965 DOI: 10.3389/fneur.2022.999035] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 09/05/2022] [Indexed: 11/16/2022] Open
Abstract
Brain injury resulting from sepsis, or sepsis-associated encephalopathy (SAE), occurs due to impaired end-organ perfusion, dysregulated inflammation affecting the central nervous system (CNS), blood-brain barrier (BBB) disruption, mitochondrial dysfunction, oxidative stress, accumulation of toxic neuropeptides and impaired toxin clearance secondary to sepsis-induced hepatic and renal dysfunction. The gut microbiome becomes pathologically altered in sepsis, which likely contributes to the pathogenesis of SAE. Herein, we review the literature detailing dysregulation of microbiota-gut-brain axis (MGBA) in SAE and highlight potential therapeutic strategies to modulate the gut microbiome to mitigate sepsis-induced brain injury.
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Affiliation(s)
- Brooke Barlow
- Department of Pharmacy, Memorial Hermann The Woodlands Health System, Houston, TX, United States
| | - Sameer Ponnaluri
- Department of Neurology, University of Florida College of Medicine, Gainesville, FL, United States
| | - Ashley Barlow
- Department of Pharmacy, MD Anderson Cancer Center, Houston, TX, United States
| | - William Roth
- Department of Neurology, University of Florida College of Medicine, Gainesville, FL, United States
- *Correspondence: William Roth
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22
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Sciatic nerve stimulation alleviates acute neuropathic pain via modulation of neuroinflammation and descending pain inhibition in a rodent model. J Neuroinflammation 2022; 19:153. [PMID: 35706025 PMCID: PMC9199305 DOI: 10.1186/s12974-022-02513-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 06/01/2022] [Indexed: 11/12/2022] Open
Abstract
Background Neuropathic pain (NP) is characterized by abnormal activation of pain conducting pathways and manifests as mechanical allodynia and thermal hypersensitivity. Peripheral nerve stimulation is used for treatment of medically refractory chronic NP and has been shown to reduce neuroinflammation. However, whether sciatic nerve stimulation (SNS) is of therapeutic benefit to NP remains unclear. Moreover, the optimal frequency for SNS is unknown. To address this research gap, we investigated the effect of SNS in an acute NP rodent model. Methods Rats with right L5 nerve root ligation (NRL) or Sham surgery were used. Ipsilateral SNS was performed at 2 Hz, 20 Hz, and 60 Hz frequencies. Behavioral tests were performed to assess pain and thermal hypersensitivity before and after NRL and SNS. Expression of inflammatory proteins in the L5 spinal cord and the immunohistochemical alterations of spinal cord astrocytes and microglia were examined on post-injury day 7 (PID7) following NRL and SNS. The involvement of the descending pain modulatory pathway was also investigated. Results Following NRL, the rats showed a decreased pain threshold and latency on the von Frey and Hargreaves tests. The immunofluorescence results indicated hyperactivation of superficial spinal cord dorsal horn (SCDH) neurons. Both 2-Hz and 20-Hz SNS alleviated pain behavior and hyperactivation of SCDH neurons. On PID7, NRL resulted in elevated expression of spinal cord inflammatory proteins including NF-κB, TNF-α, IL-1β, and IL-6, which was mitigated by 2-Hz and 20-Hz SNS. Furthermore, 2-Hz and 20-Hz SNS suppressed the activation of spinal cord astrocytes and microglia following NRL on PID7. Activity of the descending serotoninergic pain modulation pathway showed an increase early on PID1 following 2-Hz and 20-Hz SNS. Conclusions Our results support that both 2-Hz and 20-Hz SNS can alleviate NP behaviors and hyperactivation of pain conducting pathways. We showed that SNS regulates neuroinflammation and reduces inflammatory protein expression, astrocytic gliosis, and microglia activation. During the early post-injury period, SNS also facilitates the descending pain modulatory pathway. Taken together, these findings support the therapeutic potential of SNS for acute NP. Supplementary Information The online version contains supplementary material available at 10.1186/s12974-022-02513-y.
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23
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Silverå Ejneby M, Jakešová M, Ferrero JJ, Migliaccio L, Sahalianov I, Zhao Z, Berggren M, Khodagholy D, Đerek V, Gelinas JN, Głowacki ED. Chronic electrical stimulation of peripheral nerves via deep-red light transduced by an implanted organic photocapacitor. Nat Biomed Eng 2022; 6:741-753. [PMID: 34916610 DOI: 10.1038/s41551-021-00817-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 07/28/2021] [Indexed: 11/09/2022]
Abstract
Implantable devices for the wireless modulation of neural tissue need to be designed for reliability, safety and reduced invasiveness. Here we report chronic electrical stimulation of the sciatic nerve in rats by an implanted organic electrolytic photocapacitor that transduces deep-red light into electrical signals. The photocapacitor relies on commercially available semiconducting non-toxic pigments and is integrated in a conformable 0.1-mm3 thin-film cuff. In freely moving rats, fixation of the cuff around the sciatic nerve, 10 mm below the surface of the skin, allowed stimulation (via 50-1,000-μs pulses of deep-red light at wavelengths of 638 nm or 660 nm) of the nerve for over 100 days. The robustness, biocompatibility, low volume and high-performance characteristics of organic electrolytic photocapacitors may facilitate the wireless chronic stimulation of peripheral nerves.
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Affiliation(s)
- Malin Silverå Ejneby
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden.,Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden
| | - Marie Jakešová
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden.,Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic
| | - Jose J Ferrero
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY, USA
| | - Ludovico Migliaccio
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden.,Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden.,Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic
| | - Ihor Sahalianov
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden
| | - Zifang Zhao
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Magnus Berggren
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden
| | - Dion Khodagholy
- Department of Electrical Engineering, Columbia University, New York, NY, USA
| | - Vedran Đerek
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden. .,Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden. .,Department of Physics, Faculty of Science, University of Zagreb, Zagreb, Croatia.
| | - Jennifer N Gelinas
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY, USA. .,Department of Neurology, Columbia University Medical Center, New York, NY, USA.
| | - Eric Daniel Głowacki
- Laboratory of Organic Electronics, Campus Norrköping, Linköping University, Norrköping, Sweden. .,Wallenberg Centre for Molecular Medicine, Linköping University, Linköping, Sweden. .,Central European Institute of Technology, Brno University of Technology, Brno, Czech Republic.
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24
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Caravaca AS, Gallina AL, Tarnawski L, Shavva VS, Colas RA, Dalli J, Malin SG, Hult H, Arnardottir H, Olofsson PS. Vagus nerve stimulation promotes resolution of inflammation by a mechanism that involves Alox15 and requires the α7nAChR subunit. Proc Natl Acad Sci U S A 2022; 119:e2023285119. [PMID: 35622894 PMCID: PMC9295760 DOI: 10.1073/pnas.2023285119] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Accepted: 02/09/2022] [Indexed: 12/31/2022] Open
Abstract
Nonresolving inflammation underlies a range of chronic inflammatory diseases, and therapeutic acceleration of resolution of inflammation may improve outcomes. Neural reflexes regulate the intensity of inflammation (for example, through signals in the vagus nerve), but whether activation of the vagus nerve promotes the resolution of inflammation in vivo has been unknown. To investigate this, mice were subjected to electrical vagus nerve stimulation (VNS) or sham surgery at the cervical level followed by zymosan-induced peritonitis. The duration of inflammation resolution was significantly reduced and efferocytosis was significantly increased in mice treated with VNS as compared with sham. Lipid mediator (LM) metabololipidomics revealed that mice treated with VNS had higher levels of specialized proresolving mediators (SPMs), particularly from the omega-3 docosahexaenoic (DHA) and docosapentaenoic (n-3 DPA) metabolomes, in peritoneal exudates. VNS also shifted the ratio between proinflammatory and proresolving LMs toward a proresolving profile, but this effect by VNS was inverted in mice deficient in 12/15-lipoxgenase (Alox15), a key enzyme in this SPM biosynthesis. The significant VNS-mediated reduction of neutrophil numbers in peritoneal exudates was absent in mice deficient in the cholinergic α7-nicotinic acetylcholine receptor subunit (α7nAChR), an essential component of the inflammatory reflex. Thus, VNS increased local levels of SPM and accelerated resolution of inflammation in zymosan-induced peritonitis by a mechanism that involves Alox15 and requires the α7nAChR.
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Affiliation(s)
- April S. Caravaca
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, 171 76, Sweden
| | - Alessandro L. Gallina
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, 171 76, Sweden
| | - Laura Tarnawski
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, 171 76, Sweden
| | - Vladimir S. Shavva
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
| | - Romain A. Colas
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, United Kingdom
| | - Jesmond Dalli
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, United Kingdom
| | - Stephen G. Malin
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
| | - Henrik Hult
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, 171 76, Sweden
- Department of Mathematics, KTH Royal Institute of Technology, Stockholm, 114 28, Sweden
| | - Hildur Arnardottir
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
| | - Peder S. Olofsson
- Laboratory of Immunobiology, Division of Cardiovascular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, 171 76, Sweden
- Stockholm Center for Bioelectronic Medicine, MedTechLabs, Karolinska University Hospital, Solna, 171 76, Sweden
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, 11030
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25
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Wright JP, Mughrabi IT, Wong J, Mathew J, Jayaprakash N, Crosfield C, Chang EH, Chavan SS, Tracey KJ, Pavlov VA, Al-Abed Y, Zanos TP, Zanos S, Datta-Chaudhuri T. A fully implantable wireless bidirectional neuromodulation system for mice. Biosens Bioelectron 2022; 200:113886. [PMID: 34995836 PMCID: PMC9258776 DOI: 10.1016/j.bios.2021.113886] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/02/2021] [Accepted: 12/10/2021] [Indexed: 01/09/2023]
Abstract
Novel research in the field of bioelectronic medicine requires neuromodulation systems that pair high-performance neurostimulation and bio-signal acquisition hardware with advanced signal processing and control algorithms. Although mice are the most commonly used animal in medical research, the size, weight, and power requirements of such bioelectronic systems either preclude use in mice or impose significant constraints on experimental design. Here, a fully-implantable recording and stimulation neuromodulation system suitable for use in mice is presented, measuring 2.2 cm3 and weighing 2.8 g. The bidirectional wireless interface allows simultaneous readout of multiple physiological signals and complete control over stimulation parameters, and a wirelessly rechargeable battery provides a lifetime of up to 5 days on a single charge. The device was implanted to deliver vagus nerve stimulation (n = 12 animals) and a functional neural interface (capable of inducing acute bradycardia) was demonstrated with lifetimes exceeding three weeks. The design utilizes only commercially-available electrical components and 3D-printed packaging, with the goal of facilitating widespread adoption and accelerating discovery and translation of future bioelectronic therapeutics.
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Affiliation(s)
- Jason P Wright
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Ibrahim T Mughrabi
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Jason Wong
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Jose Mathew
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Naveen Jayaprakash
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Christine Crosfield
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Eric H Chang
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Sangeeta S Chavan
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Kevin J Tracey
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Valentin A Pavlov
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Theodoros P Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, United States.
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26
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Caravaca AS, Levine YA, Drake A, Eberhardson M, Olofsson PS. Vagus Nerve Stimulation Reduces Indomethacin-Induced Small Bowel Inflammation. Front Neurosci 2022; 15:730407. [PMID: 35095387 PMCID: PMC8789651 DOI: 10.3389/fnins.2021.730407] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 12/16/2021] [Indexed: 12/11/2022] Open
Abstract
Crohn's disease is a chronic, idiopathic condition characterized by intestinal inflammation and debilitating gastrointestinal symptomatology. Previous studies of inflammatory bowel disease (IBD), primarily in colitis, have shown reduced inflammation after electrical or pharmacological activation of the vagus nerve, but the scope and kinetics of this effect are incompletely understood. To investigate this, we studied the effect of electrical vagus nerve stimulation (VNS) in a rat model of indomethacin-induced small intestinal inflammation. 1 min of VNS significantly reduced small bowel total inflammatory lesion area [(mean ± SEM) sham: 124 ± 14 mm2, VNS: 62 ± 14 mm2, p = 0.002], intestinal peroxidation and chlorination rates, and intestinal and systemic pro-inflammatory cytokine levels as compared with sham-treated animals after 24 h following indomethacin administration. It was not known whether this observed reduction of inflammation after VNS in intestinal inflammation was mediated by direct innervation of the gut or if the signals are relayed through the spleen. To investigate this, we studied the VNS effect on the small bowel lesions of splenectomized rats and splenic nerve stimulation (SNS) in intact rats. We observed that VNS reduced small bowel inflammation also in splenectomized rats but SNS alone failed to significantly reduce small bowel lesion area. Interestingly, VNS significantly reduced small bowel lesion area for 48 h when indomethacin administration was delayed. Thus, 1 min of electrical activation of the vagus nerve reduced indomethacin-induced intestinal lesion area by a spleen-independent mechanism. The surprisingly long-lasting and spleen-independent effect of VNS on the intestinal response to indomethacin challenge has important implications on our understanding of neural control of intestinal inflammation and its potential translation to improved therapies for IBD.
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Affiliation(s)
- April S. Caravaca
- Laboratory of Immunobiology, Department of Medicine, Karolinska University Hospital, Solna, Sweden
- MedTechLabs, BioClinicum, Stockholm Center for Bioelectronic Medicine, Karolinska University Hospital, Solna, Sweden
- SetPoint Medical, Inc., Valencia, CA, United States
| | - Yaakov A. Levine
- Laboratory of Immunobiology, Department of Medicine, Karolinska University Hospital, Solna, Sweden
- MedTechLabs, BioClinicum, Stockholm Center for Bioelectronic Medicine, Karolinska University Hospital, Solna, Sweden
- SetPoint Medical, Inc., Valencia, CA, United States
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, New York, NY, United States
| | - Anna Drake
- SetPoint Medical, Inc., Valencia, CA, United States
| | - Michael Eberhardson
- Laboratory of Immunobiology, Department of Medicine, Karolinska University Hospital, Solna, Sweden
- MedTechLabs, BioClinicum, Stockholm Center for Bioelectronic Medicine, Karolinska University Hospital, Solna, Sweden
- Department of Gastroenterology and Hepatology, University Hospital of Linköping, Linköping, Sweden
- Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Peder S. Olofsson
- Laboratory of Immunobiology, Department of Medicine, Karolinska University Hospital, Solna, Sweden
- MedTechLabs, BioClinicum, Stockholm Center for Bioelectronic Medicine, Karolinska University Hospital, Solna, Sweden
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, New York, NY, United States
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27
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Yakovlev OA, Yudin MA, Chepur SV, Vengerovich NG, Stepanov AV, Babkin AA. Non-Specific Targets for Correction of Pneumonia Caused by Aerosols Containing Damaging Factors of Various Nature. BIOLOGY BULLETIN REVIEWS 2022; 12. [PMCID: PMC9749646 DOI: 10.1134/s207908642206010x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review article provides data on the current state of the pathogenesis peculiarities of body and lung inflammation (pneumonia) under the influence of damaging factors of various nature: infectious agents, chemical toxicants, as well as incorporated radionuclides, etc. The peculiarities of inflammation itself, as a typical pathological process, are considered. Information on mediators that induce the so-called pro-resolving phase of inflammation manifestations is given. Approaches to the neuroimmune correction of non-specific inflammation are substantiated. Data on the following alternative approaches to the correction of nonspecific inflammation are summarized: factors of the coagulation system, modulators of the integrated stress response, and modulators of sigma-1 receptors. Based on the data presented, general directions for the treatment of nonspecific pneumonia are formulated, including reflexogenic and anti-inflammatory therapy in combination with multimodal drugs, as well as pro-resolving therapy in combination with drugs that prevent fibrosis.
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Affiliation(s)
- O. A. Yakovlev
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia
| | - M. A. Yudin
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia ,North-Western State Medical University named after I.I. Mechnikov, 195067 St. Petersburg, Russia
| | - S. V. Chepur
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia
| | - N. G. Vengerovich
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia ,Saint-Petersburg State Chemical Pharmaceutical University, 197376 St. Petersburg, Russia
| | - A. V. Stepanov
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia
| | - A. A. Babkin
- State Research Experimental Institute of Military Medicine, 198515 St. Petersburg, Russia
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28
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Fischer L, Barop H, Ludin SM, Schaible HG. Regulation of acute reflectory hyperinflammation in viral and other diseases by means of stellate ganglion block. A conceptual view with a focus on Covid-19. Auton Neurosci 2021; 237:102903. [PMID: 34894589 DOI: 10.1016/j.autneu.2021.102903] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 10/23/2021] [Accepted: 11/01/2021] [Indexed: 12/15/2022]
Abstract
Whereas the autonomic nervous system (ANS) and the immune system used to be assigned separate functions, it has now become clear that the ANS and the immune system (and thereby inflammatory cascades) work closely together. During an acute immune response (e. g., in viral infection like Covid-19) the ANS and the immune system establish a fast interaction resulting in "physiological" inflammation. Based on our knowledge of the modulation of inflammation by the ANS we propose that a reflectory malfunction of the ANS with hyperactivity of the sympathetic nervous system (SNS) may be involved in the generation of acute hyperinflammation. We believe that sympathetic hyperactivity triggers a hyperresponsiveness of the immune system ("cytokine storm") with consecutive tissue damage. These reflectory neuroimmunological and inflammatory cascades constitute a general reaction principle of the organism under the leadership of the ANS and does not only occur in viral infections, although Covid-19 is a typical current example therefore. Within the overreaction several interdependent pathological positive feedback loops can be detected in which the SNS plays an important part. Consequently, there is a chance to regulate the hyperinflammation by influencing the SNS. This can be achieved by a stellate ganglion block (SGB) with local anesthetics, temporarily disrupting the pathological positive feedback loops. Thereafter, the complex neuroimmune system has the chance to reorganize itself. Previous clinical and experimental data have confirmed a favorable outcome in hyperinflammation (including pneumonia) after SGB (measurable e. g. by a reduction in proinflammatory cytokines).
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Affiliation(s)
- Lorenz Fischer
- University of Bern, Interventional Pain Management, General Internal Medicine, Schwanengasse 5/7, 3011 Bern, Switzerland.
| | - Hans Barop
- Neural Therapy, Friedrich-Legahn-Str. 2, 22587 Hamburg, Germany
| | | | - Hans-Georg Schaible
- University Hospital Jena, Institute of Physiology1/Neurophysiology, Teichgraben 8, 07743 Jena, Germany.
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Tarnawski L, Olofsson PS. Inflammation neuroscience: neuro-immune crosstalk and interfaces. Clin Transl Immunology 2021; 10:e1352. [PMID: 34754449 PMCID: PMC8558388 DOI: 10.1002/cti2.1352] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/01/2021] [Accepted: 10/10/2021] [Indexed: 02/06/2023] Open
Abstract
Inflammation is a key process in antimicrobial defence and tissue repair, and failure to properly regulate inflammation can result in tissue damage and death. Neural circuits play important roles throughout the course of an inflammatory response, and the neurophysiological and molecular mechanisms are only partly understood. Here, we review key evidence for the neural regulation of inflammation and discuss emerging technologies to further map and harness this neurophysiology, a cornerstone in the rapidly evolving field of inflammation neuroscience.
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Affiliation(s)
- Laura Tarnawski
- Laboratory of ImmunobiologyDivision of Cardiovascular MedicineDepartment of Medicine, SolnaKarolinska InstitutetStockholmSweden
- Stockholm Center for Bioelectronic MedicineMedTechLabsBioclinicumKarolinska University HospitalSolnaSweden
| | - Peder S Olofsson
- Laboratory of ImmunobiologyDivision of Cardiovascular MedicineDepartment of Medicine, SolnaKarolinska InstitutetStockholmSweden
- Stockholm Center for Bioelectronic MedicineMedTechLabsBioclinicumKarolinska University HospitalSolnaSweden
- Institute of Bioelectronic MedicineFeinstein Institutes for Medical ResearchManhassetNYUSA
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30
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Falvey A, Metz CN, Tracey KJ, Pavlov VA. Peripheral nerve stimulation and immunity: the expanding opportunities for providing mechanistic insight and therapeutic intervention. Int Immunol 2021; 34:107-118. [PMID: 34498051 DOI: 10.1093/intimm/dxab068] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2021] [Accepted: 09/07/2021] [Indexed: 12/29/2022] Open
Abstract
Pre-clinical research advances our understanding of the vagus nerve-mediated regulation of immunity and clinical trials successfully utilize electrical vagus nerve stimulation in the treatment of patients with inflammatory disorders. This symbiotic relationship between pre-clinical and clinical research exploring the vagus nerve-based 'inflammatory reflex' has substantially contributed to establishing the field of bioelectronic medicine. Recent studies identify a crosstalk between the vagus nerve and other neural circuitries in controlling inflammation and delineate new neural immunoregulatory pathways. Here we outline current mechanistic insights into the role of vagal and non-vagal neural pathways in neuro-immune communication and inflammatory regulation. We also provide a timely overview of expanding opportunities for bioelectronic neuromodulation in the treatment of various inflammatory disorders.
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Affiliation(s)
- Aidan Falvey
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, United States
| | - Christine N Metz
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, United States.,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, United States
| | - Kevin J Tracey
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, United States.,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, United States
| | - Valentin A Pavlov
- The Feinstein Institutes for Medical Research, Northwell Health, Manhasset, United States.,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, United States
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31
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Datta-Chaudhuri T. Closed-loop neuromodulation will increase the utility of mouse models in Bioelectronic Medicine. Bioelectron Med 2021; 7:10. [PMID: 34193309 PMCID: PMC8244222 DOI: 10.1186/s42234-021-00071-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 06/01/2021] [Indexed: 01/16/2023] Open
Abstract
Mouse models have been of tremendous benefit to medical science for the better part of a century, yet bioelectronic medicine research using mice has been limited to mostly acute studies because of a lack of tools for chronic stimulation and sensing. A wireless neuromodulation platform small enough for implantation in mice will significantly increase the utility of mouse models in bioelectronic medicine. This perspective examines the necessary functionality of such a system and the technical challenges needed to be overcome for its development. Recent progress is examined and the outlook for the future of implantable devices for mice is discussed.
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Affiliation(s)
- Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell Health, 350 Community Drive, Manhasset, NY, 11030, USA. .,Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, 500 Hofstra University, Hempstead, NY, 11549, USA.
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32
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Saxena S, Kruys V, Vamecq J, Maze M. The Role of Microglia in Perioperative Neuroinflammation and Neurocognitive Disorders. Front Aging Neurosci 2021; 13:671499. [PMID: 34122048 PMCID: PMC8193130 DOI: 10.3389/fnagi.2021.671499] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 05/04/2021] [Indexed: 12/14/2022] Open
Abstract
The aseptic trauma of peripheral surgery activates a systemic inflammatory response that results in neuro-inflammation; the microglia, the resident immunocompetent cells in the brain, are a key element of the neuroinflammatory response. In most settings microglia perform a surveillance role in the brain detecting and responding to “invaders” to maintain homeostasis. However, microglia have also been implicated in producing harm possibly by changing its phenotype from its beneficial, anti-inflammatory state (termed M2) into an injurious pro-inflammatory state (termed M1); it is likely that there are intermediates states between these polar phenotypes and some consider that a gradient exists with a number of intermediates, rather than a strict dichotomy between M1 and M2. In the pro-inflammatory phenotypes, microglia can disrupt synaptic plasticity such as long- term potentiation that can result in disorders of learning and memory of the type observed in Peri-operative Neurocognitive Disorders. Therefore, investigators have sought strategies to prevent microglia from provoking this adverse event in the perioperative period. In preclinical studies microglia can be depleted by removing trophic factors required for its maintenance; subsequent repopulation with a more beneficial microglial phenotype may result in memory enhancement, improved sensory motor function, as well as suppression of neuroinflammatory and oxidative stress pathways. Another approach consists of preventing microglial activation using the non-specific P38 MAP kinase blockers such as minocycline. Perhaps a more physiologic approach is the use of inhibitors of potassium (K+) channels that are required to convert the microglia into an active state. In this context the specific K+ channels that are implicated are termed Kv1.3 and KCa3.1 and high selective inhibitors for each have been developed. Data are accumulating demonstrating the utility of these K+ channel blockers in preventing Perioperative Neurocognitive Disorders.
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Affiliation(s)
- Sarah Saxena
- Department of Anesthesia, University Hospital Center (CHU de Charleroi), Charleroi, Belgium.,Department of Anesthesia and Perioperative Care, Center for Cerebrovascular Research, University of California, San Francisco, San Francisco, CA, United States
| | - Veronique Kruys
- Laboratory of Molecular Biology of the Gene, Department of Molecular Biology, ULB Immunology Research Center (UIRC), Free University of Brussels (ULB), Gosselies, Belgium
| | - Joseph Vamecq
- Inserm, CHU Lille, Univ Lille, Department of Biochemistry and Molecular Biology, Laboratory of Hormonology, Metabolism-Nutrition and Oncology (HMNO), Center of Biology and Pathology (CBP) Pierre-Marie Degand, CHRU Lille, University of North France, Lille, France
| | - Mervyn Maze
- Department of Anesthesia and Perioperative Care, Center for Cerebrovascular Research, University of California, San Francisco, San Francisco, CA, United States
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33
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Eberhardson M, Levine YA, Tarnawski L, Olofsson PS. The brain-gut axis, inflammatory bowel disease and bioelectronic medicine. Int Immunol 2021; 33:349-356. [PMID: 33912906 DOI: 10.1093/intimm/dxab018] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/26/2021] [Indexed: 12/21/2022] Open
Abstract
The hallmark of inflammatory bowel diseases (IBD) is chronic intestinal inflammation with typical onset in adolescents and young adults. An abundance of neutrophils is seen in the inflammatory lesions, but adaptive immunity is also an important player in the chronicity of the disease. There is an unmet need for new treatment options since modern medicines such as biological therapy with anti-cytokine antibodies still leave a substantial number of patients with persisting disease activity. The role of the central nervous system and its interaction with the gut in the pathophysiology of IBD have been brought to attention both in animal models and in humans after the discovery of the inflammatory reflex. The suggested control of gut immunity by the brain-gut axis represents a novel therapeutic target suitable for bioelectronic intervention. In this review, we discuss the role of the inflammatory reflex in gut inflammation and the recent advances in the treatment of IBD by intervening with the brain-gut axis through bioelectronic devices.
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Affiliation(s)
- Michael Eberhardson
- Department of Gastroenterology and Hepatology, University Hospital of Linköping, 581 91 Linköping, Sweden.,Department of Medicine, Center for Bioelectronic Medicine, Bioclinicum, Karolinska Institutet, 171 64 Stockholm, Sweden.,Department of Health, Medicine and Caring Sciences, Linköping University, 581 83 Linköping, Sweden
| | - Yaakov A Levine
- Department of Medicine, Center for Bioelectronic Medicine, Bioclinicum, Karolinska Institutet, 171 64 Stockholm, Sweden.,SetPoint Medical, Valencia, CA 91355, USA
| | - Laura Tarnawski
- Department of Medicine, Center for Bioelectronic Medicine, Bioclinicum, Karolinska Institutet, 171 64 Stockholm, Sweden
| | - Peder S Olofsson
- Department of Medicine, Center for Bioelectronic Medicine, Bioclinicum, Karolinska Institutet, 171 64 Stockholm, Sweden.,Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
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34
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Hellysaz A, Hagbom M. Understanding the Central Nervous System Symptoms of Rotavirus: A Qualitative Review. Viruses 2021; 13:v13040658. [PMID: 33920421 PMCID: PMC8069368 DOI: 10.3390/v13040658] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 01/08/2023] Open
Abstract
This qualitative review on rotavirus infection and its complications in the central nervous system (CNS) aims to understand the gut–brain mechanisms that give rise to CNS driven symptoms such as vomiting, fever, feelings of sickness, convulsions, encephalitis, and encephalopathy. There is substantial evidence to indicate the involvement of the gut–brain axis in symptoms such as vomiting and diarrhea. The underlying mechanisms are, however, not rotavirus specific, they represent evolutionarily conserved survival mechanisms for protection against pathogen entry and invasion. The reviewed studies show that rotavirus can exert effects on the CNS trough nervous gut–brain communication, via the release of mediators, such as the rotavirus enterotoxin NSP4, which stimulates neighboring enterochromaffin cells in the intestine to release serotonin and activate both enteric neurons and vagal afferents to the brain. Another route to CNS effects is presented through systemic spread via lymphatic pathways, and there are indications that rotavirus RNA can, in some cases where the blood brain barrier is weakened, enter the brain and have direct CNS effects. CNS effects can also be induced indirectly as a consequence of systemic elevation of toxins, cytokines, and/or other messenger molecules. Nevertheless, there is still no definitive or consistent evidence for the underlying mechanisms of rotavirus-induced CNS complications and more in-depth studies are required in the future.
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Mughrabi IT, Hickman J, Jayaprakash N, Thompson D, Ahmed U, Papadoyannis ES, Chang YC, Abbas A, Datta-Chaudhuri T, Chang EH, Zanos TP, Lee SC, Froemke RC, Tracey KJ, Welle C, Al-Abed Y, Zanos S. Development and characterization of a chronic implant mouse model for vagus nerve stimulation. eLife 2021; 10:e61270. [PMID: 33821789 PMCID: PMC8051950 DOI: 10.7554/elife.61270] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 04/02/2021] [Indexed: 12/17/2022] Open
Abstract
Vagus nerve stimulation (VNS) suppresses inflammation and autoimmune diseases in preclinical and clinical studies. The underlying molecular, neurological, and anatomical mechanisms have been well characterized using acute electrophysiological stimulation of the vagus. However, there are several unanswered mechanistic questions about the effects of chronic VNS, which require solving numerous technical challenges for a long-term interface with the vagus in mice. Here, we describe a scalable model for long-term VNS in mice developed and validated in four research laboratories. We observed significant heart rate responses for at least 4 weeks in 60-90% of animals. Device implantation did not impair vagus-mediated reflexes. VNS using this implant significantly suppressed TNF levels in endotoxemia. Histological examination of implanted nerves revealed fibrotic encapsulation without axonal pathology. This model may be useful to study the physiology of the vagus and provides a tool to systematically investigate long-term VNS as therapy for chronic diseases modeled in mice.
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Affiliation(s)
- Ibrahim T Mughrabi
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Jordan Hickman
- Departments of Neurosurgery, University of Colorado Anschutz Medical CampusAuroraUnited States
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Naveen Jayaprakash
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Dane Thompson
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
- The Elmezzi Graduate School of Molecular MedicineManhassetUnited States
| | - Umair Ahmed
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Eleni S Papadoyannis
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York UniversityNew YorkUnited States
- Department of Neuroscience and Physiology, Neuroscience Institute, Center for Neural Science, New York University School of Medicine, New York UniversityNew YorkUnited States
- Department of Otolaryngology, New York University School of Medicine, New York UniversityNew YorkUnited States
- Howard Hughes Medical Institute Faculty Scholar, New York University School of Medicine, New York UniversityNew YorkUnited States
| | - Yao-Chuan Chang
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Adam Abbas
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Eric H Chang
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Theodoros P Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Sunhee C Lee
- Institute of Molecular Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Robert C Froemke
- Skirball Institute for Biomolecular Medicine, New York University School of Medicine, New York UniversityNew YorkUnited States
- Department of Neuroscience and Physiology, Neuroscience Institute, Center for Neural Science, New York University School of Medicine, New York UniversityNew YorkUnited States
- Department of Otolaryngology, New York University School of Medicine, New York UniversityNew YorkUnited States
- Howard Hughes Medical Institute Faculty Scholar, New York University School of Medicine, New York UniversityNew YorkUnited States
| | - Kevin J Tracey
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Cristin Welle
- Departments of Neurosurgery, University of Colorado Anschutz Medical CampusAuroraUnited States
- Department of Physiology and Biophysics, University of Colorado Anschutz Medical CampusAuroraUnited States
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, The Feinstein Institutes for Medical Research, Northwell HealthManhassetUnited States
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36
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Tang Y, Dong X, Chen G, Ye W, Kang J, Tang Y, Feng Z. Vagus Nerve Stimulation Attenuates Early Traumatic Brain Injury by Regulating the NF-κB/NLRP3 Signaling Pathway. Neurorehabil Neural Repair 2020; 34:831-843. [PMID: 32772884 DOI: 10.1177/1545968320948065] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Traumatic brain injury (TBI) is a major cause of death and disability worldwide. Oxidative stress, inflammation, and apoptosis are vital pathophysiological features post-TBI. OBJECTIVES Research has shown that vagus nerve stimulation (VNS) can attenuate oxidative stress in various diseases. However, the critical role of VNS in TBI is still not completely understood. This study investigated the protective effects and potential mechanism of VNS on TBI. METHODS Male Sprague-Dawley rats were randomized into 3 groups: sham, TBI, and TBI + VNS. The TBI model was induced in rats by the free-fall drop method. The vagal nerve trunk was separated, and VNS was performed after establishing the TBI model. RESULTS The results showed that VNS significantly ameliorated tissue damage, neurological deficits, and cerebral edema, compared with the sham VNS group. Additionally, VNS alleviated oxidative stress, inflammation, and apoptosis in the pericontusive cortex of rats after TBI. VNS also significantly suppressed expression of the nuclear factor-κB (NF-κB) protein in the nucleus and activation of the nucleotide-binding domain-like receptor protein 3 (NLRP3) inflammasome. CONCLUSIONS Taken together, the present study indicates that VNS may attenuate brain damage after TBI by inhibiting oxidative stress, inflammation, and apoptosis, possibly through the NF-κB/NLRP3 signaling pathway.
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Affiliation(s)
- Yunliang Tang
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Xiaoyang Dong
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Gengfa Chen
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Wen Ye
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Junwei Kang
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Yang Tang
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
| | - Zhen Feng
- Department of Rehabilitation Medicine, First Affiliated Hospital of Nanchang University, Nanchang, People's Republic of China
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Dirr EW, Urdaneta ME, Patel Y, Johnson RD, Campbell-Thompson M, Otto KJ. Designing a bioelectronic treatment for Type 1 diabetes: targeted parasympathetic modulation of insulin secretion. BIOELECTRONICS IN MEDICINE 2020; 3:17-31. [PMID: 33169091 PMCID: PMC7604671 DOI: 10.2217/bem-2020-0006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 06/29/2020] [Indexed: 12/31/2022]
Abstract
The pancreas is a visceral organ with exocrine functions for digestion and endocrine functions for maintenance of blood glucose homeostasis. In pancreatic diseases such as Type 1 diabetes, islets of the endocrine pancreas become dysfunctional and normal regulation of blood glucose concentration ceases. In healthy individuals, parasympathetic signaling to islets via the vagus nerve, triggers release of insulin from pancreatic β-cells and glucagon from α-cells. Using electrical stimulation to augment parasympathetic signaling may provide a way to control pancreatic endocrine functions and ultimately control blood glucose. Historical data suggest that cervical vagus nerve stimulation recruits many visceral organ systems. Simultaneous modulation of liver and digestive function along with pancreatic function provides differential signals that work to both raise and lower blood glucose. Targeted pancreatic vagus nerve stimulation may provide a solution to minimizing off-target effects through careful electrode placement just prior to pancreatic insertion.
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Affiliation(s)
- Elliott W Dirr
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA
| | - Morgan E Urdaneta
- Department of Neuroscience, University of Florida, Gainesville, FL 32611, USA
| | - Yogi Patel
- Department of Biomedical Engineering, Georgia Institute of Technology University of Florida, Gainesville, FL 32611, USA
| | - Richard D Johnson
- Department of Neuroscience, University of Florida, Gainesville, FL 32611, USA
- Department of Physiological Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Martha Campbell-Thompson
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA
- Department of Pathology, Immunology, & Laboratory Medicine University of Florida, Gainesville, FL 32611, USA
| | - Kevin J Otto
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA
- Department of Neuroscience, University of Florida, Gainesville, FL 32611, USA
- Department of Neurology, University of Florida, Gainesville, FL 32611, USA
- Department of Materials Science & Engineering, University of Florida, Gainesville, FL 32611, USA
- Department of Electrical & Computer Engineering, University of Florida, Gainesville, FL 32611, USA
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Dexmedetomidine attenuates inflammation and pancreatic injury in a rat model of experimental severe acute pancreatitis via cholinergic anti-inflammatory pathway. Chin Med J (Engl) 2020; 133:1073-1079. [PMID: 32265428 PMCID: PMC7213633 DOI: 10.1097/cm9.0000000000000766] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Excessive inflammatory responses play a critical role in the development of severe acute pancreatitis (SAP), and controlling such inflammation is vital for managing this often fatal disease. Dexmedetomidine has been reported to possess protective properties in inflammatory diseases. Therefore, this study aimed to investigate whether dexmedetomidine pre-treatment exerts an anti-inflammatory effect in rats with SAP induced by sodium taurocholate, and if so, to determine the potential mechanism. METHODS SAP was induced with sodium taurocholate. Rats received an intraperitoneal injection of dexmedetomidine 30 min before sodium taurocholate administration. α-bungarotoxin, a selective alpha-7 nicotinic acetylcholine receptor (α7nAchR) antagonist, was injected intra-peritoneally 30 min before dexmedetomidine administration. The role of the vagus nerve was evaluated by performing unilateral cervical vagotomy before the administration of dexmedetomidine. Efferent discharge of the vagal nerve was recorded by the BL-420F Data Acquisition & Analysis System. Six hours after onset, serum pro-inflammatory cytokine (tumor necrosis factor α [TNF-α] and interleukin 6 [IL-6]) levels and amylase levels were determined using an enzyme-linked immunosorbent assay and an automated biochemical analyzer, respectively. Histopathological changes in the pancreas were observed after hematoxylin and eosin staining and scored according to Schmidt criteria. RESULTS Pre-treatment with dexmedetomidine significantly decreased serum levels of TNF-α, IL-6, and amylase, strongly alleviating pathological pancreatic injury in the rat model of SAP (TNF-α: 174.2 ± 30.2 vs. 256.1±42.4 pg/ml; IL-6: 293.3 ± 46.8 vs. 421.7 ± 48.3 pg/ml; amylase: 2102.3 ± 165.3 vs. 3186.4 ± 245.2 U/L). However, the anti-inflammatory and pancreatic protective effects were abolished after vagotomy or pre-administration of α-bungarotoxin. Dexmedetomidine also significantly increased the discharge frequency and amplitude of the cervical vagus nerve in the SAP rat model (discharge frequency: 456.8 ± 50.3 vs. 332.4 ± 25.1 Hz; discharge amplitude: 33.4 ± 5.3 vs. 20.5 ± 2.9 μV). CONCLUSIONS Dexmedetomidine administration attenuated the systemic inflammatory response and local pancreatic injury caused by SAP in rats through the cholinergic anti-inflammatory pathway involving vagus- and α7nAChR-dependent mechanisms.
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