Biol Res. 2024 Nov 23;57(1):88. doi: 10.1186/s40659-024-00573-3.

ABSTRACT

BACKGROUND: Outstanding exercise performance has been associated with an exacerbated vagal outflow. Nevertheless, during high-altitude hypobaric-hypoxia (HH), there is a baroreflex-dependent parasympathetic withdrawal and exercise performance deterioration. Notably, vagal control is pivotal in exercise performance, and exogenous oxytocin (OXY) administration has been shown to enhance parasympathetic drive; however, no evidence shows their role in exercise performance during HH. Then, this study aimed to examine the effect of prolonged exogenous oxytocin (OXY) administration on exercise performance during hypobaric hypoxia (HH) in rats.

RESULTS: A vehicle group (n = 6) and an OXY group (n = 6) performed incremental exercise and baroreflex tests during both normobaric normoxia (NN) and HH (PO₂: 100 mmHg, simulated 3,500 m) prior (pre-) and after (post-) 14 days of administration. The results showed that at pre-, there were no significant differences in exercise performance between the two groups, while at post-, the OXY group exhibited similar performance between NN and HH, while the Vehicle group maintained a significant decline in performance at HH compared to NN. At post-, the Vehicle group also demonstrated a reset in the baroreflex and a worse bradycardic response in HH, which was reversed in the OXY group, while the hypoxic ventilatory response was similar in both groups.

CONCLUSION: The findings suggest prolonged OXY administration prevents impaired exercise performance and vagal control during short-term HH.

PMID:39578887 | DOI:10.1186/s40659-024-00573-3

BMJ Open. 2024 Nov 21;14(11):e089650. doi: 10.1136/bmjopen-2024-089650.

ABSTRACT

INTRODUCTION: Thyroid surgery with intraoperative nerve monitoring under total intravenous anaesthesia often requires deeper sedation due to limitations or lack of neuromuscular blocking agents, usually resulting in haemodynamic instability. Remimazolam, a newly developed sedative, is being studied for its effect on the haemodynamic profile of patients undergoing this procedure and compared with propofol.

METHODS AND ANALYSIS: This will be a single-centre, single-blind, randomised, controlled trial in American Society of Anesthesiologists I-III patients between the ages of 18 and 65 who require recurrent laryngeal nerve monitoring for thyroid surgery. Patients will be randomised 1:1 to either remimazolam besylate or propofol, with 142 cases in each group according to a randomised, computer-generated cohort. The primary outcome is the occurrence of hypotension from induction of anaesthesia to full recovery. Secondary outcomes include the administration of vasoactive agents, the number of hypotension or hypertension episodes, the cumulative duration of hypotension or hypertension, the dose of intraoperative rescue sedation and analgesia, the time to extubation and awakening and the incidence of adverse events.

ETHICS AND DISSEMINATION: Ethical approval for this study was obtained from the Medical Ethics Committee of the Affiliated Cancer Hospital and Institute of Guangzhou Medical University (2023-2024). The study protocol was modified according to the reviewers’ comments, and the revised version was approved by the Ethics Committee (2024 Research Ethics Amendment No. 3). On completion of the study, we will commit to ensuring that the results are made available to the public, regardless of the outcome. This will include either publication in an appropriate journal or oral presentation at academic conferences.

TRIAL REGISTRATION NUMBER: ChiCTR2300076583.

PMID:39578027 | DOI:10.1136/bmjopen-2024-089650

Seizure. 2024 Nov 8;123:148-151. doi: 10.1016/j.seizure.2024.11.005. Online ahead of print.

ABSTRACT

INTRODUCTION: Individuals with tuberous sclerosis complex (TSC) often present with refractory epilepsy and may be undergoing treatment with vagus nerve stimulation (VNS) to control seizures. Surveillance magnetic resonance imaging (MRI) is necessary to monitor for the renal angiomyolipomas associated with TSC; however, MRI of the abdomen is not approved for patients withVNS therapy. We have many TSC patients with refractory epilelpsy who benefitted from VNS therapy, so we developed an MRI protocol that allows MRI of the abdomen to be performed in these patients to permit safe imaging of their kidneys. Here we report our results using this protocol.

METHODS: We performed a retrospective review for all TSC patients seen from 01/01/1997 to 10/01/2022 at a single center to determine VNS implantation status. Patients with VNS implants and abdomen imaging performed according to the protocol for kidney surveillance were included.

RESULTS: Sixteen patients with 48 total MRIs of the abdomen were found: 34 (71 %) scans were conducted under sedation and 14 (29 %) without sedation. None of the patients reported any adverse effects (pain or discomfort). No instances of VNS dysfunction were noted when re-interrogating the device immediately after completion of the imaging studies or at later neurology follow-up appointments. All MRI scans were of good quality for interpretation.

CONCLUSION: Abdominal MRIs performed in typical VNS exclusion zones were not associated with adverse events or VNS dysfunction. We believe this protocol is safe and permits the best method for monitoring renal disease in TSC patients with VNS.

PMID:39571475 | DOI:10.1016/j.seizure.2024.11.005

Mol Biol Rep. 2024 Nov 21;52(1):1. doi: 10.1007/s11033-024-10097-4.

ABSTRACT

BACKGROUND: As a multifunctional ecosystem, the human digestive system contains a complex network of microorganisms, collectively known as gut microbiota. This consortium composed of more than 10¹³ microorganisms and Firmicutes and Bacteroidetes are the dominant microbes. Gut microbiota is increasingly recognized for its critical role in physiological processes beyond digestion. Gut microbiota participates in a symbiotic relationship with the host and takes advantage of intestinal nutrients and mutually participates in the digestion of complex carbohydrates and maintaining intestinal functions.

METHOD AND RESULT: We reviewed the neuroactive components produced by gut microbiota. Interestingly, microbiota plays a crucial role in regulating the activity of the intestinal lymphatic system, regulation of the intestinal epithelial barrier, and maintaining the tolerance to food immunostimulating molecules. The gut-brain axis is a two-way communication pathway that links the gut microbiota to the central nervous system (CNS) and importantly is involved in neurodevelopment, cognition, emotion and synaptic transmissions. The connections between gut microbiota and CNS are via endocrine system, immune system and vagus nerve.

CONCLUSION: The gut microbiota produces common neurotransmitters and neuromodulators of the nervous system. These compounds play a role in neuronal functions, immune system regulation, gastrointestinal homeostasis, permeability of the blood brain barrier and other physiological processes. This review investigates the essential aspects of the neurotransmitters and neuromodulators produced by gut microbiota and their implications in health and disease.

PMID:39570444 | DOI:10.1007/s11033-024-10097-4

Heliyon. 2024 Sep 29;10(21):e38675. doi: 10.1016/j.heliyon.2024.e38675. eCollection 2024 Nov 15.

ABSTRACT

BACKGROUND: Acupressure has proven efficacy in symptoms management, making it valuable in clinical practice and patient care. Given the rising number of increasing publications on acupressure, we aimed to analyze the literature from the past 20 years and provided current trends and hotspot for future research directions.

METHODS: Publications on acupressure from January 1, 2004 through May 1, 2024 were retrieved from the Web of Science database. The extracted records underwent thorough analysis based on publication year, research area, journal, countries/regions, organization, authors, and keywords. The bibliometric analysis was conducted using Citespace and Microsoft Excel software.

RESULTS: Of the 1,929 screened records, 770 publications were identified. The annual number of acupressure has gradually increased, with the 45 % of the total publication occurring from 2020 to 2024. Among countries and institutions, China (252 articles) and Hong Kong Polytechnic University (41 articles) have the highest number of publications. Notably, USA and Hong Kong Polytechnic University exhibits the highest centrality score in cooperative network among countries/regions and institutions. Chao Hsing Yeh from the Cizik School of Nursing, University of Texas Health Science Center, was the most prolific author with 22 papers. Evidence-Based Comple Alt, with 53 articles, is the journal with the most publications. According to the keyword, timeline diagram and prominence mapping analysis, we believe that “insomnia”, “labor”, “waist circumference”, “reliability” and “vagus nerve stimulation” related clusters may be new hotspots in the field of acupressure.

CONCLUSION: This study presents the research trajectory of acupressure over the past 20 years, providing a foundation for future research and highlighting the significant contributions of nursing researchers. By analyzing research trends and hotsport, nursing professionals can integrate acupressure more effectively into holistic patient care, improving quality of life, and contributing to traditional Chinese medicine.

PMID:39568827 | PMC:PMC11577180 | DOI:10.1016/j.heliyon.2024.e38675

Brain Behav Immun. 2024 Nov 19;124:28-39. doi: 10.1016/j.bbi.2024.11.023. Online ahead of print.

ABSTRACT

The vagus nerve is a crucial component of the parasympathetic nervous system, facilitating communication between the brain and various organs, including the ears, heart, lungs, pancreas, spleen, and gastrointestinal tract. The caudal nucleus of the solitary tract in the brainstem is the initial site regulated by the vagus nerve in brain-body communication, including the interactions with immune system. Increasing evidence suggests that the gut-brain axis, via the vagus nerve, may play a role in the development and progression of psychiatric, neurologic, and inflammation-related disorders. Population-based cohort studies indicate that truncal vagotomy may reduce the risk of neurological disorders such as Parkinson’s disease and Alzheimer’s disease, underscoring the vagus nerve’s significance in these conditions. Given its role in the cholinergic anti-inflammatory pathway, α7 nicotinic acetylcholine receptors present a potential therapeutic target. Additionally, noninvasive transcutaneous auricular vagus nerve stimulation (taVNS) shows promise as a therapeutic tool for these disorders. This article provides a historical review of the vagus nerve and explores its role in brain-body communication. Finally, we discuss future directions, including the potential of noninvasive taVNS as a therapeutic approach.

PMID:39566667 | DOI:10.1016/j.bbi.2024.11.023

Brain Stimul. 2024 Nov 18;17(6):1283-1285. doi: 10.1016/j.brs.2024.11.008. Online ahead of print.

NO ABSTRACT

PMID:39566596 | DOI:10.1016/j.brs.2024.11.008

Sci Transl Med. 2024 Nov 20;16(774):eadl2184. doi: 10.1126/scitranslmed.adl2184. Epub 2024 Nov 20.

ABSTRACT

Inflammatory bowel diseases (IBDs) are chronic debilitating conditions without cure, the etiologies of which are unknown, that shorten the lifespans of 7 million patients worldwide by nearly 10%. Here, we found that decreased autonomic parasympathetic tone resulted in increased IBD susceptibility and mortality in mouse models of disease. Conversely, vagal stimulation restored neuromodulation and ameliorated colitis by inhibiting the posttranslational modification SUMOylation through a mechanism independent of the canonical interleukin-10/α7 nicotinic cholinergic vagal pathway. Colonic biopsies from patients with IBDs and mouse models showed an increase in small ubiquitin-like modifier (SUMO)2 and SUMO3 during active disease. In global genetic knockout mouse models, the deletion of Sumo3 protected against development of colitis and delayed onset of disease, whereas deletion of Sumo1 halted the progression of colitis. Bone marrow transplants from Sumo1-knockout (KO) but not Sumo3-KO mice into wild-type mice conferred protection against development of colitis. Electric stimulation of the cervical vagus nerve before the induction of colitis inhibited SUMOylation and delayed the onset of colitis in Sumo1-KO mice and resulted in milder symptoms in Sumo3-KO mice. Treatment with TAK-981, a first-in-class inhibitor of the SUMO-activating enzyme, ameliorated disease in three murine models of IBD and reduced intestinal permeability and bacterial translocation in a severe model of the disease, suggesting the potential to reduce progression to sepsis. These results reveal a pathway of vagal neuromodulation that reprograms endogenous stress-adaptive responses through inhibition of SUMOylation and suggest SUMOylation as a therapeutic target for IBD.

PMID:39565873 | DOI:10.1126/scitranslmed.adl2184

Front Neurosci. 2024 Nov 5;18:1471387. doi: 10.3389/fnins.2024.1471387. eCollection 2024.

ABSTRACT

BACKGROUND: Melatonin (MLT) and its receptor deficiency have been shown to be associated with type 2 diabetes mellitus (T2DM). Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive alternative intervention for patients suffering from hyperglycemia. Here, we aimed to investigate the role of taVNS on blood glucose modulation via intestinal melatonin receptors (MRs) and MLT secretion in hyperglycemia.

METHODS: Adult male Zucker diabetes fatty (ZDF) rats and Zucker lean (ZL) littermates were used. Forty ZDF rats were randomized into ZDF, taVNS, Px + taVNS and Lu + Px + taVNS groups (Px: pinealectomy, Lu: Luzindole). ZL rats served as a control group for comparison with ZDF rats without involvement in the taVNS intervention. Thirty min-taVNS interventions (2/15 Hz, 2 mA, 30 min/days) were administered once daily under anesthesia for 3 consecutive weeks in taVNS, Px + taVNS and Lu + Px + taVNS groups. Body weight and fasting blood glucose (FBG) were measured weekly in all rats, and real-time blood glucose was tested in the ZL and ZDF groups before, during and after the taVNS intervention. Plasma MLT concentration and the expression of MRs in the duodenum, jejunum and ileum were measured by the end of experiments.

RESULTS: Compared with the ZL group, the level of FBG and body weight increased (all p < 0.01), plasma MLT secretion and the expression of MRs in duodenum, jejunum and ileum of ZDF rats decreased obviously (all p < 0.05), respectively. TaVNS can significantly reverse the hyperglycemia by regulating the non-pineal-derived MLT and MRs system in Px + taVNS group. Compared with the ZDF group, the expression of different intestinal MRs in the taVNS group was increased and more compactly arranged (both p < 0.05), the level of plasma MLT secretion was up-regulated (p < 0.01), and FBG and body weight were decreased (both p < 0.01). Meanwhile, after taVNS intervention in rats in the Px + taVNS group, we observed an increase in MLT secretion and the number of intestinal MRs compared with the taVNS group (all p > 0.05). In contrast, ZDF rats in which the pineal gland was excised by taVNS intervention and injected with the MRs antagonist Luzindole did not show these changes.

CONCLUSION: The glucose reduction effect of taVNS may be related to regulating MLT levels and expressing intestinal MRs.

PMID:39564526 | PMC:PMC11573758 | DOI:10.3389/fnins.2024.1471387

Commun Biol. 2024 Nov 19;7(1):1536. doi: 10.1038/s42003-024-07222-1.

ABSTRACT

Neuromodulation by vagus nerve stimulation (VNS) provides therapeutic benefits in multiple medical conditions, including epilepsy and clinical depression, but underlying mechanisms of action are not well understood. Cervical vagus nerve biopsies were procured from transplant organ donors for high resolution light microscopy (LM) and transmission electron microscopy (TEM) to map the human fascicular and sub-fascicular organization. Cervical vagal segments show laterality with right sided dominance in fascicle numbers and cross-sectional areas as well as sexual dimorphism with female dominance in fascicle numbers. The novel and unprecedented detection of numerous small fascicles by high resolution LM and TEM expand the known fascicle size range and morphological diversity of the human vagus nerve. Ground truth TEM quantification of all myelinated and unmyelinated axons within individual nerve fascicles show marked sub-fascicular heterogeneity of nerve fiber numbers, size, and myelination. A heuristic action potential interpreter (HAPI) tool predicts VNS-evoked compound nerve action potentials (CNAPs) generated by myelinated and unmyelinated nerve fibers and validates functional dissimilarity between fascicles. Our findings of laterality, sexual dimorphism, and an expanded range of fascicle size heterogeneity provide mechanistic insights into the varied therapeutic responses and off-target effects to VNS and may guide new refinement strategies for neuromodulation.

PMID:39562711 | PMC:PMC11576867 | DOI:10.1038/s42003-024-07222-1