Autoimmune Diseases, Autonomic Dysfunction, Epilepsy, Inflammatory Bowel Diseases
Conditions
Keywords
epilepsy, vagal, autoimmune, autonomic, inflammatory bowel disease, immune
Brief summary
Vagal nerve stimulation is a neurosurgical procedure consisting of implantation of an impulse generator battery with leads placed into the vagus nerve in the neck. This procedure was FDA approved for epilepsy in the 1990s and is commonly performed as an outpatient surgery. The mechanism of action is not well understood; however it is increasingly recognized that electrical stimulation of the vagus nerve may impact other organ systems in the body including the immune and gastrointestinal systems. Concrete characterization of the peripheral effects of VNS in human gut microbiome and immune systems will: (1) elucidate peripheral mechanism of action of chronic VNS therapy, (2) identify peripheral preoperative biomarker of VNS efficacy, and (3) create a foundation for research investigating new GM and IM-related disease indications for VNS. The primary objective of this study is to characterize the pre- and post-operative oral and gut microbiome of patients implanted with vagal nerve stimulator (VNS) for epilepsy. Secondary objectives of this study include: (1) to characterize the pre-operative and post-operative immune profile of patients undergoing VNS implantation for epilepsy, (2) to elucidate whether oral and/or gut microbiota changes are related to VNS efficacy for epilepsy and (3) identification of a biomarker predicting VNS efficacy.
Interventions
DEVICEVagal nerve stimulation (VNS)
Implantation with vagal nerve stimulator for epilepsy
Sponsors
LivaNova
Norton Foundation
University of Louisville
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE
Intervention model description
Prospective single-arm with internal control group
Eligibility
Sex/Gender
ALL
Age
0 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
1. Undergoing VNS implantation for the first time as a treatment for epilepsy and 2. Documented follow up with a Louisville-based neurologist in the past 1 year. If at the University of Utah or Baylor University documented ability to travel to their corresponding neurologist. 3. Documented ability to travel to Louisville for outpatient medical care. If at the University of Utah or Baylor University documented ability to travel to their facilities.
Exclusion criteria
1. Previous treatment with VNS (other than the one implanted for this study) 2. Current pregnancy (contraindication to surgery) 3. Active infection 4. History of cancer or treatment with chemotherapy 5. History of autoimmune disease: Patients who received high effect anticholinergic medication within 30 days of enrollment will be excluded, whereas moderate to low effect anticholinergic medication will be discussed with and decided by the PI. 6. If any high effect anticholinergic medication is started after enrollment, it will be the PI's decision to drop or postpone the corresponding visit or exclude the patient entirely. 7. Patients who received high effect corticosteroids within 30 days of enrollment will be excluded, whereas moderate to low effect corticosteroids will be discussed with and decided by the PI. 8. If any high effect corticosteroid is started after enrollment, it will be the PI's decision to drop or postpone the corresponding visit or exclude the patient entirely. 9. Treatment with antiarrhythmic or (heart) rate controlling medication, 10. Pre-existing cardiac arrhythmia or presence of cardiac pacemaker / defibrillator
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Inflammatory Profile 4 - Intestinal inflammation and permeability markers | 1 year | sCD163 (nanograms/mL), sCD14 (micrograms/mL), CRP (mg/L), and I-FABP (picograms/mL) are markers of intestinal inflammation and permeability and will be measured using an enzyme-linked immunosorbent assay (ELISA) performed on cell-free supernatants such as plasma, serum and urine. The units of measurement |
| Metagenomic microbiome profile | 1 year | Stool and saliva specimens will be used to generate metagenomic profiles of gut flora populations. Pre- and post-VNS gut profiles will be compared. It is important to note that the genomic profile of all gut flora is the outcome, rather than the presence or absence of any specific type of bacteria. |
| Bowel movement frequency | 1 year | A brief clinical questionnaire regarding the frequency and consistency of bowel movements will be administered. This will be done pre- and post-VNS implantation in each patient. Any medications to manage diarrhea and constipation will be carefully recorded as well as their efficacy. |
| Bowel habits | 1 year | A clinical bowel habits questionnaire will be administered at each study visit to determine changes in bowel habits pre and post operatively. Additionally, the Bristol stool scale will be assessed at each visit. |
| Immune Profile 1 - Flow cytometric profiling of cell populations | 1 year | One milliliter of whole blood from each subject will be aliquoted into separate tube and directly stained with fluorochrome-conjugated antibodies to investigate the cellular composition of the blood. Subtypes of lymphocytes, monocytes and granulocytes will be defined by set phenotypic marker expression |
| Immune Profile 2 - Ex vivo stimulation of cells in whole blood | 1 year | Up to 10 ml of the whole blood will be cultured in 24-well tissue culture plates in the presence and absence of innate immune cell activators, such as TLR ligands, LPS, CpG ODN, poly I:C or flagellin, or adaptive immune activators such as anti-CD3/anti-CD28 beads, PHA or recall antigens. Culture supernatants and cells will be harvested at the needed time points and analyzed via MSD and qPCR, respectively. |
| Inflammatory Profile 1 - Meso Scale Discovery (or MSD) analysis for pro-inflammatory cytokines/chemokines | 1 year | Serum electrochemiluminescence detection analysis of the following cytokines/chemokines: IFNg, IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, TNFα. Units in Picograms/ml or Nanograms/ml depending on the specific chemokine/cytokine |
| Inflammatory Profile 2 - Meso Scale Discovery (or MSD) analysis for metabolic hormones | 1 year | Serum electrochemiluminescence detection analysis of the following hormones: GLP-1, insulin, Glucagon, Leptin. All in picograms/mL. |
| Inflammatory Profile 3 - Metabolomics for Short Chain Fatty acids (SCFAs) | 1 year | Short Chain Fatty Acids (SCFAs) in both feces and serum will be derivatized, extracted in organic solvent and analyzed using Gas chromatography-mass spectrometry (GC-MS) to determine the levels of short-chain fatty acids. To the microbial community SCFAs are a necessary waste product, required to balance redox equivalent production in the anaerobic environment of the gut. SCFAs are saturated aliphatic organic acids that consist of one to six carbons of which acetate (C2), propionate (C3), and butyrate (C4) are the most abundant (≥95%). Acetate, propionate, and butyrate are present in an approximate molar ratio of 60:20:20 and will be measured in picomoles/mL. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Epilepsy severity | 1 year | Patients will keep a log of seizure type, keeping careful track of the frequency of each type, how long each seizure lasts and what medical interventions are taken to stop each seizure. Additionally, 1 year Engel outcome will be assessed. |
Countries
United States
Contacts
Primary ContactIan S Mutchnick, MD
Backup ContactMeena A Vessell, MD
Outcome results
None listed