Clinical Research Directory

Mandibular Stretching and 4-4-8 Breathing Exercises on Autonomic Nervous System Activity

Mandibular stretching exercises and breathing techniques may influence autonomic nervous system activity, muscle tone, and psychological state. This randomized controlled trial aims to investigate the effects of mandibular stretching exercise and the 4-4-8 breathing exercise on autonomic nervous system activity, muscle tone, and psychological parameters in healthy university students. Participants will be randomly assigned to intervention groups and evaluated before and after the intervention period.

PSYLIVER-PILOTE: Involvement of the Autonomic Nervous System in Hepatocellular Carcinoma (HCC)

Chronic liver diseases affect 1.5 billion people worldwide and can lead to cirrhosis and hepatocellular carcinoma (HCC), which ranks as the third leading cause of cancer-related mortality globally. Despite advances in the treatment of hepatitis B and C, metabolic diseases, and addiction, HCC incidence continues to rise. In France, between 2010 and 2015, the five-year survival rate for liver cancer (90% of which is HCC) was 18% for men and 19% for women. Treatment of HCC is based on the BCLC classification (Barcelona Clinic Liver Cancer), which evaluates both cancer progression and liver function (Child-Pugh classification). Patients at early stages (0 or A) have a survival rate of over 5 years, while those at more advanced stages (C or D) have significantly lower survival rates, highlighting the importance of better early detection tools. Current screening for HCC in cirrhotic patients involves biannual US-scan. However, ultrasound sensitivity for detecting tumors smaller than 2 cm is around 25%. Therefore, developing personalized strategies to predict and detect early-stage HCC is crucial to improving patient outcomes. Various clinical and biological scores have been developed to assess the risk of developing HCC in cirrhotic patients, but these scores remain imperfect. Molecular heterogeneity in HCC, as revealed by transcriptomic studies, could explain the variability in outcomes and treatment responses. This heterogeneity in occurrence, phenotype, and progression of HCC suggests individual singularities that are not yet well understood. These individual singularities are likely linked to the autonomic nervous system (ANS), particularly in the central nervous system (CNS), which regulates various physiological processes. The ANS consists of the sympathetic nervous system (SNS), mainly adrenergic, and the parasympathetic nervous system (PNS), mainly cholinergic. These two systems function antagonistically but with different temporal dynamics. A better understanding of the interaction between tumor cells and their environment through the ANS could lead to the identification of new biomarkers to predict HCC development and therapeutic targets. The role of the ANS in cancer development has been explored in various cancers, including prostate, stomach, pancreatic, breast, and ovarian cancers, where the ANS regulates inflammation and immune responses. In chronic liver diseases, the liver is innervated by both sympathetic and parasympathetic fibers, and this innervation plays a role in regulating metabolism, liver regeneration, and fibrosis progression. Chronic liver disease etiologies, such as alcohol consumption, metabolic syndrome, and viral hepatitis, disrupt the balance between the SNS and PNS, contributing to liver dysfunction. The severity of liver damage is linked to autonomic dysfunction, and heart rate variability, a marker of PNS activity, is correlated with survival in patients with terminal-stage HCC. Our recent research has shown that patients with HCC exhibit a reconfiguration of the intrahepatic ANS, with a consistent cholinergic orientation at the neuro-hepatic synapse. Patients with parasympathetic orientation (as compared to sympathetic orientation) have more aggressive tumors, shorter survival, and, from a pharmacological perspective, anticholinergics increase sensitivity to targeted HCC therapies. Tumor cells and cytotoxic lymphocytes are most strongly associated with cholinergic receptor enrichment and depletion, respectively. In this context, the PSYLIVER-PILOTE study builds on these findings by investigating the involvement of the ANS in HCC through non-invasive extra-hepatic measures. The SNS and PNS are connected to brain regions involved in cognitive, emotional, and social information processing, such as the anterior cingulate cortex, insula, ventromedial prefrontal cortex, amygdala, and hypothalamus. These brain areas are involved in cognitive control and emotional processing. Additionally, experimental data from polyvagal theory and neurovisceral integration theory highlight the role of the ANS in regulating cognitive, emotional, and social processes, as well as psycho-behavioral traits. For instance, confronting a person with cognitive tasks and emotional or social information alters the balance of sympathetic and parasympathetic activity. Similar changes are observed in psycho-behavioral disorders like depression, emotional dysregulation, stress, and aggression. Thus, the PSYLIVER-PILOTE study aims to identify extra-hepatic markers of ANS activity associated with HCC, analyzing both electrophysiological indices (from the peripheral nervous system) and psycho-behavioral indices (from the central nervous system). This project could open new avenues for early HCC detection and the development of personalized treatments

App-based Breathing Program for Migraine Relief

Migraine is one of the most common neurological disorders, characterized by recurrent headaches, sensitivity to light and movement, nausea, and autonomic dysregulation. Although mind-body interventions like biofeedback have shown their efficacy, they remain underutilized due to barriers such as transportation, time constraints, lack of awareness, stigma, and cost. A targeted approach to enhancing HRV is HRV biofeedback (HRVB), a technique using visual or auditory feedback to help people regulate HRV through slow-paced breathing and positive emotional regulation to promote ANS balance and emotional resilience. Investigators will conduct a remotely delivered pilot RCT of an 8-week, 10 min/day, novel app-based HRVB intervention compared to a sham control intervention (matching intervention time and attention with no biofeedback component) in adult with chronic migraine. Investigators hypothesize data collected from the study will: a) support the feasibility and acceptability of the remotely delivered app-based HRVB intervention among adults with chronic migraine, and b) provide insights into refining the intervention by examining patterns of change in migraine and psychological outcomes from pre- to post-intervention.

Frequency-Dependent Effects of Auricular Vagus Nerve Stimulation on Autonomic and Cardiovascular Parameters

This randomized, sham-controlled, crossover study investigates the acute autonomic effects of transcutaneous cervical vagus nerve stimulation (tcVNS) applied at five different frequencies (0 Hz/sham, 10 Hz, 25 Hz, 50 Hz, 100 Hz) in healthy adults. The primary objective is to determine how stimulation frequency modulates heart rate variability (HRV), blood pressure, and respiratory rate. The study aims to establish a frequency-specific dose-response model using validated physiological measurements.

Effect of an Aerobic Exercise Session on Cardiovascular and Autonomic Parameters of Adults With Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy is a genetic heart disease with symptoms that may include dyspnea and fatigue predominantly on exertion, with or without chest pain, palpitations, syncope/presyncope and sudden cardiac death, mostly in young individuals, often without symptoms. Due to the higher cardiovascular risk described for individuals with hypertrophic cardiomyopathy, it is extremely important to create non-pharmacological strategies that can minimize the evolution of cardiovascular risk factors found in this population. The objective of the study will be to evaluate the effect of an aerobic exercise session on the ratio between the low frequency (LF) and high frequency (HF) bands of heart rate variability, endothelial function through flow-mediated dilation and systolic and diastolic blood pressure during the 24-hour period in adult individuals with hypertrophic cardiomyopathy. The study design will be a randomized crossover clinical trial with individuals aged 18 to 59 years, of both sexes, randomized by lottery and divided into two groups: Exercise group and control group without exercise. An exercise stress test will be performed and on a new date the individuals will perform a supervised session of moderate-intensity aerobic exercise on a horizontal stationary bicycle for 50 minutes or will remain seated in an air-conditioned room for the same period of time. Subsequently, the procedures will be crossed. It is expected to find improvements in the parameters of endothelial function, autonomic modulation and 24-hour blood pressure in adult individuals with non-obstructive hypertrophic cardiomyopathy undergoing a session of aerobic physical exercise when compared to a control session without exercise.

Cardiovascular and Cerebrovascular Control in Healthy Subjects

The aim of the study is to evaluate autonomic function and cerebrovascular control in 60 healthy subjects by means of noninvasive analysis of time series variability. To this extent, heart period, systolic and mean arterial blood pressure, cerebral blood velocity, peripheral resistances, respiration will be recorded from subjects during an orthostatic challenge. The interactions between autonomic cardiovascular function, cerebrovascular and peripheral control will be evaluated exploiting the most advanced signal processing techniques.

The Efficacy of Aerobic Exercise Training on Autonomic Nervous System and Endothelial Function in Patients with Compensated Cirrhosis

The goal of this clinical trial is to explore the impact of a 16-week aerobic exercise regimen on the autonomic nervous system and endothelial function in patients with compensated cirrhosis who have physical inactivity. The primary research question is: 1\) What effect does 16 weeks of aerobic exercise have on changes in the autonomic nervous system and endothelial function in cirrhotic patients? Additionally, the secondary research questions are: 1. How does a 16-week aerobic exercise program influence changes in muscle mass, muscle strength, and physical performance in cirrhotic patients? 2. Is there a correlation between muscle mass and parameters of the autonomic nervous system in cirrhotic patients? Participants in the intervention group will undergo 150 minutes of moderate aerobic exercise per week for 16 weeks, accompanied by a personalized nutritional plan (1.2 grams of protein per kilogram of ideal body weight per day and a calorie intake of 35 kilocalories per kilogram of ideal body weight per day). The control group will solely receive nutritional guidance and maintain their physical inactivity. The researchers will compare outcomes between these two groups.

Longitudinal Evolution of Biomarkers of Dysautonomia and Inflammation During Sepsis in Children

The Autonomic Nervous System (ANS) regulates the inflammatory response in real time, just as it controls heart rate and other vital functions. Many studies have investigated induced stimulation of the vagus nerve and its therapeutic effect in inhibiting TNFα (Tumor Necrosis Factor alpha) secretion, and therefore the risk of hypotension, septic shock, organ dysfunction during inflammation. While the anti-inflammatory effect of the autonomic nervous system on inflammation has been well studied, conversely, the effect of major inflammation on the balance of the autonomic nervous system is more difficult to understand. The inflammatory reflex could be overwhelmed and the regulatory centers of the brainstem dysregulated during situations of extreme inflammation.

Effect Of Robotic Rehabilitation And Vagus Nerve Stimulation In Ischemia Stroke Patients

This study was conducted in patients with ischemic stroke; This study was conducted to examine the effect of robotic rehabilitation and transcutaneous auricular vagal nerve stimulation applied in addition to robotic rehabilitation on the patient's functional level and autonomic nervous system. 40 people over the age of 18 participated in the study. They were randomly divided into two groups: robotic rehabilitation and transcutaneous auricular vagal nerve stimulation applied in addition to robotic rehabilitation. While the robotic rehabilitation group received Lokomat and neurological rehabilitation, the other group received stimulation with the Vagustim device, which is applied non-invasively through the ear, in addition to Lokomat and neurological rehabilitation. Spasticity, autonomic nervous system, walking speed, motor function, quality of life, muscle activity and pain were evaluated in both groups before starting treatment and six weeks after treatment. In the study, significance was evaluated at p\<0.05 level.