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Zafeiropoulos S, Ahmed U, Bikou A, Mughrabi IT, Stavrakis S, Zanos S. Vagus nerve stimulation for cardiovascular diseases: Is there light at the end of the tunnel? Trends Cardiovasc Med 2024; 34:327-337. [PMID: 37506989 DOI: 10.1016/j.tcm.2023.07.003] [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: 05/16/2023] [Revised: 06/12/2023] [Accepted: 07/17/2023] [Indexed: 07/30/2023]
Abstract
Autonomic dysfunction and chronic inflammation contribute to the pathogenesis and progression of several cardiovascular diseases (CVD), such as heart failure with preserved ejection fraction, atherosclerotic CVD, pulmonary arterial hypertension, and atrial fibrillation. The vagus nerve provides parasympathetic innervation to the heart, vessels, and lungs, and is also implicated in the neural control of inflammation through a neuroimmune pathway involving the spleen. Stimulation of the vagus nerve (VNS) can in principle restore autonomic balance and suppress inflammation, with potential therapeutic benefits in these diseases. Although VNS ameliorated CVD in several animal models, early human studies have demonstrated variable efficacy. The purpose of this review is to discuss the rationale behind the use of VNS in the treatment of CVD, to critically review animal and human studies of VNS in CVD, and to propose possible means to overcome the challenges in the clinical translation of VNS in CVD.
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Affiliation(s)
- Stefanos Zafeiropoulos
- Elmezzi Graduate School of Molecular Medicine at Northwell Health, Manhasset, NY, USA; Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Alexia Bikou
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Ibrahim T Mughrabi
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Stavros Stavrakis
- Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Stavros Zanos
- Elmezzi Graduate School of Molecular Medicine at Northwell Health, Manhasset, NY, USA; Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA.
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Berthon A, Wernisch L, Stoukidi M, Thornton M, Tessier-Lariviere O, Fortier-Poisson P, Mamen J, Pinkney M, Lee S, Sarkans E, Annecchino L, Appleton B, Garsed P, Patterson B, Gonshaw S, Jakopec M, Shunmugam S, Edwards T, Tukiainen A, Jennings J, Lajoie G, Hewage E, Armitage O. Using neural biomarkers to personalize dosing of vagus nerve stimulation. Bioelectron Med 2024; 10:15. [PMID: 38880906 PMCID: PMC11181600 DOI: 10.1186/s42234-024-00147-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Accepted: 05/17/2024] [Indexed: 06/18/2024] Open
Abstract
BACKGROUND Vagus nerve stimulation (VNS) is an established therapy for treating a variety of chronic diseases, such as epilepsy, depression, obesity, and for stroke rehabilitation. However, lack of precision and side-effects have hindered its efficacy and extension to new conditions. Achieving a better understanding of the relationship between VNS parameters and neural and physiological responses is therefore necessary to enable the design of personalized dosing procedures and improve precision and efficacy of VNS therapies. METHODS We used biomarkers from recorded evoked fiber activity and short-term physiological responses (throat muscle, cardiac and respiratory activity) to understand the response to a wide range of VNS parameters in anaesthetised pigs. Using signal processing, Gaussian processes (GP) and parametric regression models we analyse the relationship between VNS parameters and neural and physiological responses. RESULTS Firstly, we illustrate how considering multiple stimulation parameters in VNS dosing can improve the efficacy and precision of VNS therapies. Secondly, we describe the relationship between different VNS parameters and the evoked fiber activity and show how spatially selective electrodes can be used to improve fiber recruitment. Thirdly, we provide a detailed exploration of the relationship between the activations of neural fiber types and different physiological effects. Finally, based on these results, we discuss how recordings of evoked fiber activity can help design VNS dosing procedures that optimize short-term physiological effects safely and efficiently. CONCLUSION Understanding of evoked fiber activity during VNS provide powerful biomarkers that could improve the precision, safety and efficacy of VNS therapies.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Guillaume Lajoie
- Université de Montréal and Mila-Quebec AI Institute, Montréal, Canada
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Haberbusch M, Kronsteiner B, Aigner P, Kiss A, Podesser BK, Moscato F. Importance of cardiac-synchronized vagus nerve stimulation parameters on the provoked chronotropic response for different levels of cardiac innervation. Front Physiol 2024; 15:1379936. [PMID: 38835728 PMCID: PMC11148559 DOI: 10.3389/fphys.2024.1379936] [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: 01/31/2024] [Accepted: 05/02/2024] [Indexed: 06/06/2024] Open
Abstract
Introduction The influence of vagus nerve stimulation (VNS) parameters on provoked cardiac effects in different levels of cardiac innervation is not well understood yet. This study examines the effects of VNS on heart rate (HR) modulation across a spectrum of cardiac innervation states, providing data for the potential optimization of VNS in cardiac therapies. Materials and Methods Utilizing previously published data from VNS experiments on six sheep with intact innervation, and data of additional experiments in five rabbits post bilateral rostral vagotomy, and four isolated rabbit hearts with additionally removed sympathetic influences, the study explored the impact of diverse VNS parameters on HR. Results Significant differences in physiological threshold charges were identified across groups: 0.09 ± 0.06 μC for intact, 0.20 ± 0.04 μC for vagotomized, and 9.00 ± 0.75 μC for isolated hearts. Charge was a key determinant of HR reduction across all innervation states, with diminishing correlations from intact (r = 0.7) to isolated hearts (r = 0.44). An inverse relationship was observed for the number of pulses, with its influence growing in conditions of reduced innervation (intact r = 0.11, isolated r = 0.37). Frequency and stimulation delay showed minimal correlations (r < 0.17) in all conditions. Conclusion Our study highlights for the first time that VNS parameters, including stimulation intensity, pulse width, and pulse number, crucially modulate heart rate across different cardiac innervation states. Intensity and pulse width significantly influence heart rate in innervated states, while pulse number is key in denervated states. Frequency and delay have less impact impact across all innervation states. These findings suggest the importance of customizing VNS therapy based on innervation status, offering insights for optimizing cardiac neuromodulation.
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Affiliation(s)
- Max Haberbusch
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
| | - Bettina Kronsteiner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research and Translational Surgery, Medical University of Vienna, Vienna, Austria
| | - Philipp Aigner
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Department of Cardiac Surgery, Medical University of Vienna, Vienna, Austria
| | - Attila Kiss
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research and Translational Surgery, Medical University of Vienna, Vienna, Austria
| | - Bruno Karl Podesser
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Center for Biomedical Research and Translational Surgery, Medical University of Vienna, Vienna, Austria
| | - Francesco Moscato
- Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna, Austria
- Ludwig Boltzmann Institute for Cardiovascular Research, Vienna, Austria
- Austrian Cluster for Tissue Regeneration, Vienna, Austria
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Wernisch L, Edwards T, Berthon A, Tessier-Lariviere O, Sarkans E, Stoukidi M, Fortier-Poisson P, Pinkney M, Thornton M, Hanley C, Lee S, Jennings J, Appleton B, Garsed P, Patterson B, Buttinger W, Gonshaw S, Jakopec M, Shunmugam S, Mamen J, Tukiainen A, Lajoie G, Armitage O, Hewage E. Online Bayesian optimization of vagus nerve stimulation. J Neural Eng 2024; 21:026019. [PMID: 38479016 DOI: 10.1088/1741-2552/ad33ae] [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: 03/13/2023] [Accepted: 03/13/2024] [Indexed: 04/04/2024]
Abstract
Objective.In bioelectronic medicine, neuromodulation therapies induce neural signals to the brain or organs, modifying their function. Stimulation devices capable of triggering exogenous neural signals using electrical waveforms require a complex and multi-dimensional parameter space to control such waveforms. Determining the best combination of parameters (waveform optimization or dosing) for treating a particular patient's illness is therefore challenging. Comprehensive parameter searching for an optimal stimulation effect is often infeasible in a clinical setting due to the size of the parameter space. Restricting this space, however, may lead to suboptimal therapeutic results, reduced responder rates, and adverse effects.Approach. As an alternative to a full parameter search, we present a flexible machine learning, data acquisition, and processing framework for optimizing neural stimulation parameters, requiring as few steps as possible using Bayesian optimization. This optimization builds a model of the neural and physiological responses to stimulations, enabling it to optimize stimulation parameters and provide estimates of the accuracy of the response model. The vagus nerve (VN) innervates, among other thoracic and visceral organs, the heart, thus controlling heart rate (HR), making it an ideal candidate for demonstrating the effectiveness of our approach.Main results.The efficacy of our optimization approach was first evaluated on simulated neural responses, then applied to VN stimulation intraoperatively in porcine subjects. Optimization converged quickly on parameters achieving target HRs and optimizing neural B-fiber activations despite high intersubject variability.Significance.An optimized stimulation waveform was achieved in real time with far fewer stimulations than required by alternative optimization strategies, thus minimizing exposure to side effects. Uncertainty estimates helped avoiding stimulations outside a safe range. Our approach shows that a complex set of neural stimulation parameters can be optimized in real-time for a patient to achieve a personalized precision dosing.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Guillaume Lajoie
- Université de Montréal and Mila-Quebec AI Institute, Montréal, Canada
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Tovbis D, Lee E, Koh RGL, Jeong R, Agur A, Yoo PB. Enhancing the selective electrical activation of human vagal nerve fibers: a comparative computational modeling study with validation in a rat sciatic model. J Neural Eng 2023; 20:066012. [PMID: 37963401 DOI: 10.1088/1741-2552/ad0c60] [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: 03/15/2023] [Accepted: 11/14/2023] [Indexed: 11/16/2023]
Abstract
Objective.Vagus nerve stimulation (VNS) is an emerging treatment option for a myriad of medical disorders, where the method of delivering electrical pulses can vary depending on the clinical indication. In this study, we investigated the relative effectiveness of electrically activating the cervical vagus nerve among three different approaches: nerve cuff electrode stimulation (NCES), transcutaneous electrical nerve stimulation (TENS), and enhanced TENS (eTENS). The objectives were to characterize factors that influenced nerve activation and to compare the nerve recruitment properties as a function of nerve fiber diameter.Methods.The Finite Element Model, based on data from the Visible Human Project, was implemented in COMSOL. The three simulation types were compared under a range of vertical and horizontal displacements relative to the location of the vagus nerve. Monopolar anodic stimulation was examined, along with latency and activation of different fiber sizes. Nerve activation was determined via the activating function and McIntyre-Richardson-Grill models, and activation thresholds were validated in anin-vivorodent model.Results.While NCES produced the lowest activation thresholds, eTENS generally performed superior to TENS under the range of conditions and fiber diameters, producing activation thresholds up to three times lower than TENS. eTENS also preserved its enhancement when surface electrodes were displaced away from the nerve. Anodic stimulation revealed an inhibitory region that removed eTENS benefits. eTENS also outperformed TENS by up to four times when targeting smaller diameter nerve fibers, scaling similar to a cuff electrode. In latency and activation of smaller diameter nerve fibers, eTENS results resembled those of NCES more than a TENS electrode. Activation threshold ratios were consistent inin-vivovalidation.Significance.Our findings expand upon previously identified mechanisms for eTENS and further demonstrate how eTENS emulates a nerve cuff electrode to achieve lower activation thresholds. This work further characterizes considerations required for VNS under the three stimulation methods.
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Affiliation(s)
- Daniel Tovbis
- Institute of Biomedical Engineering, University of Toronto, Toronto, Canada
| | - Eugene Lee
- Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
| | - Ryan G L Koh
- KITE Research Institute, Toronto Rehabilitation Institute, University Health Network, Toronto, Canada
| | - Rania Jeong
- Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Canada
| | - Anne Agur
- Division of Anatomy, Department of Surgery, University of Toronto, Toronto, Canada
- Rehabilitation Sciences Institute, University of Toronto, Toronto, Canada
| | - Paul B Yoo
- Institute of Biomedical Engineering, University of Toronto, Toronto, Canada
- Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
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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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Huffman WJ, Musselman ED, Pelot NA, Grill WM. Measuring and modeling the effects of vagus nerve stimulation on heart rate and laryngeal muscles. Bioelectron Med 2023; 9:3. [PMID: 36797733 PMCID: PMC9936668 DOI: 10.1186/s42234-023-00107-4] [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: 12/29/2022] [Accepted: 02/08/2023] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND Reduced heart rate (HR) during vagus nerve stimulation (VNS) is associated with therapy for heart failure, but stimulation frequency and amplitude are limited by patient tolerance. An understanding of physiological responses to parameter adjustments would allow differential control of therapeutic and side effects. To investigate selective modulation of the physiological responses to VNS, we quantified the effects and interactions of parameter selection on two physiological outcomes: one related to therapy (reduced HR) and one related to side effects (laryngeal muscle EMG). METHODS We applied a broad range of stimulation parameters (mean pulse rates (MPR), intra-burst frequencies, and amplitudes) to the vagus nerve of anesthetized mice. We leveraged the in vivo recordings to parameterize and validate computational models of HR and laryngeal muscle activity across amplitudes and temporal patterns of VNS. We constructed a finite element model of excitation of fibers within the mouse cervical vagus nerve. RESULTS HR decreased with increased amplitude, increased MPR, and decreased intra-burst frequency. EMG increased with increased MPR. Preferential HR effects over laryngeal EMG effects required combined adjustments of amplitude and MPR. The model of HR responses highlighted contributions of ganglionic filtering to VNS-evoked changes in HR at high stimulation frequencies. Overlap in activation thresholds between small and large modeled fibers was consistent with the overlap in dynamic ranges of related physiological measures (HR and EMG). CONCLUSION The present study provides insights into physiological responses to VNS required for informed parameter adjustment to modulate selectively therapeutic effects and side effects.
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Affiliation(s)
- William J. Huffman
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Eric D. Musselman
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Nicole A. Pelot
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA
| | - Warren M. Grill
- grid.26009.3d0000 0004 1936 7961Department of Biomedical Engineering, Duke University, Fitzpatrick CIEMAS, Box 90281, Room 1427, 101 Science Drive, Durham, NC 27708-0281 USA ,grid.26009.3d0000 0004 1936 7961Department of Electrical and Computer Engineering, Duke University, Durham, USA ,grid.26009.3d0000 0004 1936 7961Department of Neurobiology Engineering, Duke University, Durham, USA ,grid.26009.3d0000 0004 1936 7961Department of Neurosurgery Engineering, Duke University, Durham, USA
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Jayaprakash N, Song W, Toth V, Vardhan A, Levy T, Tomaio J, Qanud K, Mughrabi I, Chang YC, Rob M, Daytz A, Abbas A, Nassrallah Z, Volpe BT, Tracey KJ, Al-Abed Y, Datta-Chaudhuri T, Miller L, Barbe MF, Lee SC, Zanos TP, Zanos S. Organ- and function-specific anatomical organization of vagal fibers supports fascicular vagus nerve stimulation. Brain Stimul 2023; 16:484-506. [PMID: 36773779 DOI: 10.1016/j.brs.2023.02.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 02/03/2023] [Accepted: 02/03/2023] [Indexed: 02/11/2023] Open
Abstract
Vagal fibers travel inside fascicles and form branches to innervate organs and regulate organ functions. Existing vagus nerve stimulation (VNS) therapies activate vagal fibers non-selectively, often resulting in reduced efficacy and side effects from non-targeted organs. The transverse and longitudinal arrangement of fibers inside the vagal trunk with respect to the functions they mediate and organs they innervate is unknown, however it is crucial for selective VNS. Using micro-computed tomography imaging, we tracked fascicular trajectories and found that, in swine, sensory and motor fascicles are spatially separated cephalad, close to the nodose ganglion, and merge caudad, towards the lower cervical and upper thoracic region; larynx-, heart- and lung-specific fascicles are separated caudad and progressively merge cephalad. Using quantified immunohistochemistry at single fiber level, we identified and characterized all vagal fibers and found that fibers of different morphological types are differentially distributed in fascicles: myelinated afferents and efferents occupy separate fascicles, myelinated and unmyelinated efferents also occupy separate fascicles, and small unmyelinated afferents are widely distributed within most fascicles. We developed a multi-contact cuff electrode to accommodate the fascicular structure of the vagal trunk and used it to deliver fascicle-selective cervical VNS in anesthetized and awake swine. Compound action potentials from distinct fiber types, and physiological responses from different organs, including laryngeal muscle, cough, breathing, and heart rate responses are elicited in a radially asymmetric manner, with consistent angular separations that agree with the documented fascicular organization. These results indicate that fibers in the trunk of the vagus nerve are anatomically organized according to functions they mediate and organs they innervate and can be asymmetrically activated by fascicular cervical VNS.
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Affiliation(s)
| | - Weiguo Song
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Viktor Toth
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Todd Levy
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Khaled Qanud
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Yao-Chuan Chang
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Moontahinaz Rob
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Anna Daytz
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Adam Abbas
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Zeinab Nassrallah
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Bruce T Volpe
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Kevin J Tracey
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Yousef Al-Abed
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Larry Miller
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Sunhee C Lee
- Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | | | - Stavros Zanos
- Feinstein Institutes for Medical Research, Manhasset, NY, USA; Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA; Elmezzi Graduate School of Molecular Medicine, Manhasset, NY, USA.
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Ji N, Li Y, Wei J, Chen F, Xu L, Li G, Lin WH. Autonomic modulation by low-intensity focused ultrasound stimulation of the vagus nerve. J Neural Eng 2022; 19. [PMID: 36541473 DOI: 10.1088/1741-2552/aca8cd] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Objective.Our previous study has shown that low-intensity focused ultrasound stimulation (FUS) of the vagus nerve could modulate blood pressure (BP), but its underlying mechanisms remain unclear. We hypothesized that low-intensity FUS of the vagus nerve would regulate autonomic function and thus BP.Approach.17 anesthetized spontaneously hypertensive rats were treated with low-intensity FUS of the left vagus nerve for 15 min each trial. Continuous BP, heart rate, respiration rate (RR), and core body temperature were simultaneously recorded to evaluate the effects on BP and other physiological parameters. Heart rate variability (HRV), systolic BP variability, and baroreflex sensitivity were computed to evaluate the autonomic modulation function. A Control-sham group without stimulation and another Control-FUS group with non-target stimulation were also examined to exclude the influence of potential confounding factors on autonomic modulation.Main results.A prolonged significant decrease in BP, pulse pressure, RR, the normalized low-frequency power of HRV, and the low-to-high frequency power ratio of HRV were found after the low-intensity FUS of the left vagus nerve in comparison with the baseline and those of the control groups, demonstrating that activities of the sympathetic nervous system were inhibited. The prolonged significant increase of the normalized high-frequency power of HRV suggested the activation of parasympathetic activity.Significance.Low-intensity FUS of the left vagus nerve effectively improved the autonomic function by activating parasympathetic efferent and inhibiting sympathetic efferent, which contributes to BP reduction. The findings shed light on the hypotensive mechanism underlying FUS.
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Affiliation(s)
- Ning Ji
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang 110819, People's Republic of China.,CAS Key Lab of Human-Machine Intelligence-Synergy Systems and Research Center for Neural Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, People's Republic of China
| | - Yuanheng Li
- CAS Key Lab of Human-Machine Intelligence-Synergy Systems and Research Center for Neural Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, People's Republic of China
| | - Jingjing Wei
- CAS Key Lab of Human-Machine Intelligence-Synergy Systems and Research Center for Neural Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, People's Republic of China.,Department of Human Anatomy, Zhuhai Campus of Zunyi Medical University, Zhuhai 519041, People's Republic of China
| | - Fei Chen
- Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China
| | - Lisheng Xu
- College of Medicine and Biological Information Engineering, Northeastern University, Shenyang 110819, People's Republic of China
| | - Guanglin Li
- CAS Key Lab of Human-Machine Intelligence-Synergy Systems and Research Center for Neural Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, People's Republic of China
| | - Wan-Hua Lin
- CAS Key Lab of Human-Machine Intelligence-Synergy Systems and Research Center for Neural Engineering, Shenzhen Institutes of Advanced Technology (SIAT), Chinese Academy of Sciences (CAS), Shenzhen 518055, People's Republic of China
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10
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Chang YC, Ahmed U, Jayaprakash N, Mughrabi I, Lin Q, Wu YC, Gerber M, Abbas A, Daytz A, Gabalski AH, Ashville J, Dokos S, Rieth L, Datta-Chaudhuri T, Tracey KJ, Guo T, Al-Abed Y, Zanos S. kHz-frequency electrical stimulation selectively activates small, unmyelinated vagus afferents. Brain Stimul 2022; 15:1389-1404. [PMID: 36241025 PMCID: PMC10164362 DOI: 10.1016/j.brs.2022.09.015] [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: 03/24/2022] [Revised: 09/02/2022] [Accepted: 09/30/2022] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Vagal reflexes regulate homeostasis in visceral organs and systems through afferent and efferent neurons and nerve fibers. Small, unmyelinated, C-type afferents comprise over 80% of fibers in the vagus and form the sensory arc of autonomic reflexes of the gut, lungs, heart and vessels and the immune system. Selective bioelectronic activation of C-afferents could be used to mechanistically study and treat diseases of peripheral organs in which vagal reflexes are involved, but it has not been achieved. METHODS We stimulated the vagus in rats and mice using trains of kHz-frequency stimuli. Stimulation effects were assessed using neuronal c-Fos expression, physiological and nerve fiber responses, optogenetic and computational methods. RESULTS Intermittent kHz stimulation for 30 min activates specific motor and, preferentially, sensory vagus neurons in the brainstem. At sufficiently high frequencies (>5 kHz) and at intensities within a specific range (7-10 times activation threshold, T, in rats; 15-25 × T in mice), C-afferents are activated, whereas larger, A- and B-fibers, are blocked. This was determined by measuring fiber-specific acute physiological responses to kHz stimulus trains, and by assessing fiber excitability around kHz stimulus trains through compound action potentials evoked by probing pulses. Aspects of selective activation of C-afferents are explained in computational models of nerve fibers by how fiber size and myelin shape the response of sodium channels to kHz-frequency stimuli. CONCLUSION kHz stimulation is a neuromodulation strategy to robustly and selectively activate vagal C-afferents implicated in physiological homeostasis and disease, over larger vagal fibers.
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Affiliation(s)
- Yao-Chuan Chang
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Naveen Jayaprakash
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Ibrahim Mughrabi
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Qihang Lin
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Yi-Chen Wu
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Michael Gerber
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Adam Abbas
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Anna Daytz
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Arielle H Gabalski
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Jason Ashville
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Socrates Dokos
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Loren Rieth
- Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV, 26506, United States
| | - Timir Datta-Chaudhuri
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Kevin J Tracey
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Tianruo Guo
- Graduate School of Biomedical Engineering, University of New South Wales, Sydney, 2052, Australia
| | - Yousef Al-Abed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, 11030, United States; Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, United States.
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11
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Jeong H, Cho A, Ay I, Bonmassar G. Short-pulsed micro-magnetic stimulation of the vagus nerve. Front Physiol 2022; 13:938101. [PMID: 36277182 PMCID: PMC9585240 DOI: 10.3389/fphys.2022.938101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 09/01/2022] [Indexed: 11/30/2022] Open
Abstract
Vagus nerve stimulation (VNS) is commonly used to treat drug-resistant epilepsy and depression. The therapeutic effect of VNS depends on stimulating the afferent vagal fibers. However, the vagus is a mixed nerve containing afferent and efferent fibers, and the stimulation of cardiac efferent fibers during VNS may produce a rare but severe risk of bradyarrhythmia. This side effect is challenging to mitigate since VNS, via electrical stimulation technology used in clinical practice, requires unique electrode design and pulse optimization for selective stimulation of only the afferent fibers. Here we describe a method of VNS using micro-magnetic stimulation (µMS), which may be an alternative technique to induce a focal stimulation, enabling a selective fiber stimulation. Micro-coils were implanted into the cervical vagus nerve in adult male Wistar rats. For comparison, the physiological responses were recorded continuously before, during, and after stimulation with arterial blood pressure (ABP), respiration rate (RR), and heart rate (HR). The electrical VNS caused a decrease in ABP, RR, and HR, whereas µM-VNS only caused a transient reduction in RR. The absence of an HR modulation indicated that µM-VNS might provide an alternative technology to VNS with fewer heart-related side effects, such as bradyarrhythmia. Numerical electromagnetic simulations helped estimate the optimal coil orientation with respect to the nerve to provide information on the electric field’s spatial distribution and strength. Furthermore, a transmission emission microscope provided very high-resolution images of the cervical vagus nerve in rats, which identified two different populations of nerve fibers categorized as large and small myelinated fibers.
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Affiliation(s)
- Hongbae Jeong
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Annabel Cho
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
- Department of Bioengineering, Harvard University, Cambridge, MA, United States
| | - Ilknur Ay
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
| | - Giorgio Bonmassar
- Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
- *Correspondence: Giorgio Bonmassar,
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12
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Mun J, Lee J, Park E, Park SM. Frequency-dependent depression of the NTS synapse affects the temporal response of the antihypertensive effect of auricular vagus nerve stimulation (aVNS). J Neural Eng 2022; 19. [PMID: 35905707 DOI: 10.1088/1741-2552/ac857a] [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: 03/02/2022] [Accepted: 07/29/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVES Auricular vagus nerve stimulation (aVNS) has recently emerged as a promising neuromodulation modality for blood pressure (BP) reduction due to its ease of use although its efficacy is still limited compared to direct baroreflex stimulation. Previous studies have also indicated that synaptic depression of nucleus tractus solitarius (NTS) in the baroreflex pathway depends on stimulus frequency. However, the nature of this frequency dependence phenomenon on antihypertensive effect has been unknown for aVNS. We aimed to investigate the antihypertensive effect of aVNS considering frequency-dependent depression characteristic in the NTS synapse. We explored NTS activation and BP reduction induced by aVNS and by direct secondary neuron stimulation (DS). APPROACH Both protocols were performed with recording of NTS activation and BP response with stimulation for each frequency parameter (2, 4, 20, 50, and 80 Hz). MAIN RESULTS The BP recovery time constant was significantly dependent on the frequency of DS and aVNS (DS - 2 Hz: 8.17 ± 4.98; 4 Hz: 9.73 ± 6.3; 20 Hz: 6.61 ± 3.28; 50 Hz: 4.93 ± 1.65; 80 Hz: 4.00 ± 1.43, p < 0.001, Kruskal-Wallis H-test / aVNS - 2 Hz: 4.02 ± 2.55; 4 Hz: 8.13 ± 4.05; 20 Hz: 6.40 ± 3.16; 50 Hz: 5.18 ± 2.37; 80 Hz: 3.13 ± 1.29, p < 0.05, Kruskal-Wallis H-test) despite no significant BP reduction at 2 Hz compared to sham groups (p > 0.05, Mann-Whitney U-test). SIGNIFICANCE Our observations suggest that the antihypertensive effect of aVNS is influenced by the characteristics of frequency-dependent synaptic depression in the NTS neuron in terms of the BP recovery time. These findings suggest that the antihypertensive effect of aVNS can be improved with further understanding of the neurological properties of the baroreflex associated with aVNS, which is critical to push this new modality for clinical interpretation.
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Affiliation(s)
- Junseung Mun
- Department of Convergence IT Engineering, POSTECH, IMSLAB, 2nd floor, C5 building, POSTECH 77, Cheongam-ro, Nam-gu, South Korea, Pohang, 37673, Korea (the Republic of)
| | - Jiho Lee
- Department of Convergence IT Engineering, Pohang University of Science and Technology, IMSLAB, 2nd floor, C5 building, POSTECH 77, Cheongam-ro, Nam-gu, South Korea, Pohang, 37673, Korea (the Republic of)
| | - Eunkyoung Park
- Department of Medical and Mechatronics Engineering, Soonchunhyang University, Chungnam 31538, Asan, Korea, Asan, Chungcheongnam-do, 31538, Korea (the Republic of)
| | - Sung-Min Park
- POSTECH, IMSLAB, 2nd floor, C5 building, POSTECH 77, Cheongam-ro, Nam-gu, South Korea, Pohang, 37673, Korea (the Republic of)
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13
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Choudhary RC, Ahmed U, Shoaib M, Alper E, Rehman A, Kim J, Shinozaki K, Volpe BT, Chavan S, Zanos S, Tracey KJ, Becker LB. Threshold adjusted vagus nerve stimulation after asphyxial cardiac arrest results in neuroprotection and improved survival. Bioelectron Med 2022; 8:10. [PMID: 35854394 PMCID: PMC9297561 DOI: 10.1186/s42234-022-00092-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 06/24/2022] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Vagus nerve stimulation (VNS) has shown therapeutic potential in a variety of different diseases with many ongoing clinical trials. The role of VNS in reducing ischemic injury in the brain requires further evaluation. Cardiac arrest (CA) causes global ischemia and leads to the injury of vital organs, especially the brain. In this study, we investigated the protective effects of customized threshold-adjusted VNS (tVNS) in a rat model of CA and resuscitation. METHODS Sprague-Dawley rats underwent 12 min asphyxia-CA followed by resuscitation. Rats were assigned to either post-resuscitation tVNS for 2 h or no-tVNS (control). tVNS was applied by electrode placement in the left cervical vagus nerve. To optimize a threshold, we used animal's heart rate and determined a 15-20% drop from baseline levels as the effective and physiological threshold for each animal. The primary endpoint was 72 h survival; secondary endpoints included neurological functional recovery, reduction in brain cellular injury (histopathology), cardiac and renal injury parameters (troponin I and creatinine levels, respectively). RESULTS In comparison to the control group, tVNS significantly improved 72 h survival and brain functional recovery after 12 minutes of CA. The tVNS group demonstrated significantly reduced numbers of damaged neurons in the CA1 hippocampal region of the brain as compared to the control group. Similarly, the tVNS group showed decreased trend in plasma troponin I and creatinine levels as compared to the control group. CONCLUSIONS Our findings suggest that using tVNS for 2 h after 12 minutes of CA attenuates ischemia neuronal cell death, heart and kidney damage, and improves 72 h survival with improved neurological recovery.
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Affiliation(s)
- Rishabh C Choudhary
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Department of Emergency Medicine, Northwell Health, Manhasset, NY, USA
| | - Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Muhammad Shoaib
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Eric Alper
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Abdul Rehman
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA
| | - Junhwan Kim
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
- Department of Emergency Medicine, Northwell Health, Manhasset, NY, USA
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Koichiro Shinozaki
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA
- Department of Emergency Medicine, Northwell Health, Manhasset, NY, USA
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
| | - Bruce T Volpe
- Zucker School of Medicine at Hofstra/Northwell, Hempstead, NY, USA
- Center for Molecular Medicine, Feinstein Institutes for Medical Research, Northwell Health, Manhasset, NY, USA
| | - Sangeeta Chavan
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Kevin J Tracey
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA
| | - Lance B Becker
- Laboratory for Critical Care Physiology, Feinstein Institutes for Medical Research, Northwell Health, 350 Community Dr, Manhasset, NY, 11030, USA.
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, NY, USA.
- Department of Emergency Medicine, Northwell Health, Manhasset, NY, USA.
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14
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Ahmed U, Chang YC, Zafeiropoulos S, Nassrallah Z, Miller L, Zanos S. Strategies for precision vagus neuromodulation. Bioelectron Med 2022; 8:9. [PMID: 35637543 PMCID: PMC9150383 DOI: 10.1186/s42234-022-00091-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/05/2022] [Indexed: 12/21/2022] Open
Abstract
The vagus nerve is involved in the autonomic regulation of physiological homeostasis, through vast innervation of cervical, thoracic and abdominal visceral organs. Stimulation of the vagus with bioelectronic devices represents a therapeutic opportunity for several disorders implicating the autonomic nervous system and affecting different organs. During clinical translation, vagus stimulation therapies may benefit from a precision medicine approach, in which stimulation accommodates individual variability due to nerve anatomy, nerve-electrode interface or disease state and aims at eliciting therapeutic effects in targeted organs, while minimally affecting non-targeted organs. In this review, we discuss the anatomical and physiological basis for precision neuromodulation of the vagus at the level of nerve fibers, fascicles, branches and innervated organs. We then discuss different strategies for precision vagus neuromodulation, including fascicle- or fiber-selective cervical vagus nerve stimulation, stimulation of vagal branches near the end-organs, and ultrasound stimulation of vagus terminals at the end-organs themselves. Finally, we summarize targets for vagus neuromodulation in neurological, cardiovascular and gastrointestinal disorders and suggest potential precision neuromodulation strategies that could form the basis for effective and safe therapies.
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Affiliation(s)
- Umair Ahmed
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Yao-Chuan Chang
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Stefanos Zafeiropoulos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Zeinab Nassrallah
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA
| | - Larry Miller
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA
| | - Stavros Zanos
- Institute of Bioelectronic Medicine, Feinstein Institutes for Medical Research, Manhasset, New York, USA.
- Donald and Barbara Zucker School of Medicine at Hofstra/Northwell, Hempstead, New York, USA.
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