Nycklemoe, Marin

Breathing is a physiological process that extends beyond gas exchange, linking neural, cardiovascular, glymphatic, and autonomic systems. This narrative review summarizes how breathing-based practices modulate physiological processes in the body and brain, emphasizing their applicability in clinical care. Regulating the pace and depth of breathing, particularly with relaxed exhalation, may engage vagal pathways that lower heart rate and blood pressure and promote a shift toward increased parasympathetic tone relative to sympathetic activity. Neuroimaging studies show that controlled breathing reduces activity in stress-related brain regions while enhancing networks supporting calm attention and emotional steadiness. Changes in breathing depth also influence cerebrospinal fluid movement, though direct evidence of waste clearance in humans is lacking. This review identifies populations requiring caution, including individuals with panic symptoms, significant cardiopulmonary disease, or pregnancy. Clinicians should distinguish between breathing-only and multimodal protocols when interpreting research findings, as combined interventions preclude attribution of benefit to breathing alone. Study design quality, particularly the use of active rather than waitlist controls, should inform how effect sizes are interpreted. Breathing practices are not a replacement for medical treatment but may represent accessible, low-cost adjuncts for stress reduction and cardiovascular regulation.

Introduction Burnout among healthcare professionals remains a critical public health issue linked to impaired cognition, emotional exhaustion and diminished clinical performance. Structured breathing practices have demonstrated promise in improving autonomic regulation and cerebral oxygenation, yet their feasibility, acceptability and implementation in real-world healthcare settings remain underexplored. Objectives This single-arm pilot feasibility trial aims to evaluate the feasibility, acceptability and implementation appropriateness of a structured breathing-based intervention for healthcare professionals across community-based Mayo Clinic Health System (MCHS) sites. Secondary objectives include assessing usability and engagement with the mobile breathing platform, while exploratory analyses will describe magnitude of variability and feasibility of collecting psychological and cerebral haemodynamic measures. This study will commence in November 2025 and is expected to be completed by June 2026. Methods and analysis A total of 40 clinicians (MD/DO/MBBS/PA) and nurses reporting moderate or greater burnout will be enrolled across four MCHS sites. Participants will complete a 4-month structured breathing programme delivered primarily online, supported by a mobile application for practice tracking. Assessments will occur at baseline, 2 months and 4 months, with functional near-infrared spectroscopy (fNIRS) measures of cerebral oxygenation collected at baseline and 4 months in a population subset. Primary outcomes include (1) recruitment yield, retention and adherence rates; (2) acceptability and participant satisfaction (survey and qualitative feedback); and (3) implementation appropriateness measured by the Acceptability of Intervention Measure (AIM), Intervention Appropriateness Measure (IAM) and Feasibility of Intervention Measure (FIM). Secondary outcomes include digital engagement and usability through mobile analytics and the System Usability Scale. Exploratory outcomes are psychological indicators (burnout, depression, anxiety, perceived stress, sleep, fatigue, professional fulfilment and resilience) and physiological endpoints (fNIRS). Analyses will be descriptive, summarising feasibility metrics with 95% CIs. Progression criteria (recruitment≥75%, retention≥80%, adherence≥70%, AIM/IAM/FIM≥4.0) will determine readiness for a definitive hybrid effectiveness–implementation trial. Ethics and dissemination The study is approved by the Mayo Clinic Institutional Review Board (IRB # 25-009320). All participants will provide informed consent. Study procedures ensure confidentiality, cultural sensitivity and participant safety. Data will be securely stored in REDCap and disseminated through peer-reviewed publications and scientific conference Trial registration number NCT07218458 .

Abstract INTRODUCTION Understanding neuroinflammation across the Alzheimer's disease (AD) spectrum is essential to elucidate disease mechanisms and individualize therapy. METHODS Human microglial translocator protein (TSPO) expression under inflammatory stimuli was assessed by immunoblot experiments. Ninety‐six participants were enrolled across four groups: cognitively unimpaired amyloid (CU A) + and −, mild cognitive impaired (MCI) A+, and Alzheimer's disease dementia (ADD) A+. Neuroinflammation using 11 C‐ER176 TSPO positron emission tomography (PET) was compared to amyloid and tau PET. Correlations between neuroinflammation, amyloid, and tau pathology were examined across disease stages. RESULTS TSPO was upregulated in human microglia under AD‐like inflammatory conditions. Neuroinflammation, defined by PET TSPO, increased in CU A+ participants and became more widespread with increasing disease severity, aligning with worsening amyloid and tau pathology. Associations with tau were particularly extensive in temporal and parietal regions. DISCUSSION These findings suggest probable amyloid association with early microglial activation, while tau pathology is closely tied to wider distribution of neuroinflammation. Highlights TSPO expression increases in human microglia under AD‐like inflammation. 11 C‐ER176 PET shows stage‐dependent neuroinflammation across the AD spectrum. Neuroinflammation overlaps with tau and is more widespread in amyloid‐positive individuals. Activity peaks in MCI, stabilizes later, and relates to vascular and neurodegenerative changes.

Abstract Background The tau PET imaging with 18F‐flortacipir (18F‐FTP) has focused interest in accurately tracking longitudinal tau changes in Alzheimer's disease [1]. Thus, minimizing variability is critical. Off‐target signal has the potential to complicate interpretation of tau‐PET imaging due to potential spillover or bleed‐in effects, with increased effects seen in later stages of Alzheimer's due to cerebral atrophy and proximity of off‐target areas to relevant cortical areas[2]. Previously, we demonstrated the effect of uptake period activity on 18F‐FTP signal. With increasing recent interest in demographic factors that may affect off‐target binding, we investigated the effect of age in extra‐cerebral off‐target signal in 18F‐FTP PET imaging. Method Standard 18F‐FTP PET protocol was performed in 330 participants. Two independent readers measured tau uptake in predetermined off‐target regions, including extraocular muscle, meninges, and occipital bone among others. Linear regression models assessed the relationship between participants’ age, sex, and tau uptake values (SUV and SUVr) (SUV = (Tissue radioactivity concentration / Injected dose) / Body weight & SUVr = SUV of target region/ SUV of reference region.) Result Sex had a significant effect on off‐target signal in most brain regions, with variable positive or negative correlation based on area. Notably, SUV in the eyeball‐retina, occipital bone, upper skull meninges all showed significant positive correlation with sex, with ‘male’ status generally associated with lower SUV. The greatest effect of sex was observed in superior skull meninges, occipital bone, and internal carotid artery ( p <0.001). Age showed minimally affected SUV and SUVr in off‐target regions. SUVr values show a significant correlation with SUV values of upper skull meninges in sex. Cognitive status did not significantly affect off‐target SUV. Conclusion We observed that sex significantly affected extra‐brain off‐target signal in 18F‐FTP PET imaging, while age has minimal effect, adding to previous evidence of off‐target binding within brain regions. Further evaluation is necessary to understand the age‐related effects on off‐target regions. As a result, the variability introduced by sex may pose challenges to studying tau accumulation.

Abstract Background Neuroinflammation plays a crucial role in neuronal damage, synaptic dysfunction, and impaired neurogenesis, significantly contributing to Alzheimer's Disease (AD) progression. To address this, we assessed ER176's effectiveness in detecting neuroinflammation in cognitively unimpaired (CU) A–, CU A+, mild cognitive impairment (MCI), and AD participants, with a particular focus on their amyloid and tau status. This research aims to help identify suitable candidates for specialized treatment when adversely impacted by neuroinflammation. Method Participants from the Mayo Clinic Study of Aging were recruited for this study. The study included four participant groups: CU A– ( n = 25), CU A+ ( n = 25), MCI A+ ( n = 25), and AD ( n = 15). We explored the variations in neuroinflammation PET results among different groups. Result When compared to CU A–, both CU A+ and MCI A+ groups (Figure 1) showed greater regional neuroinflammation. AD exhibited more widely affected regions with neuroinflammation (temporal, occipital, and parietal lobes) than CU A‐ over the PVC spectrum (Figure 1). Minimally more neuroinflammation was seen (temporal lobes) in MCI A+ than CU A+ (Figure 1). AD had more widespread regional neuroinflammation vs CU A+ (Figure 1) than in MCI A+ vs CU+. The least difference in neuroinflammation is seen in MCI A+ vs AD (Figure 1). For A+ vs A‐, A+ showed more widespread neuroinflammation (Figure 2). T+ (tau>=1.29) vs T‐ (tau<1.29) showed more neuro inflammation with T+ (Figure 2). Comparisons varied modestly in significance level with PVC method (Figures 1 and 2). Conclusion The findings demonstrate that neuroinflammatory changes are associated with AD pathology. Even at early stages, neuroinflammation is associated with CU+. As the condition progresses, neuroinflammation extends to more brain regions and is associated with increased A+ and T+ pathology in MCI A+ and AD. These results suggest an early and persistent role of neuroinflammation in the progression AD pathology, indicating that therapy options could include early anti‐inflammatory intervention, even prior to clinical symptoms, along with treatment during clinical manifestations. PVC methods used may provide somewhat variable results.

Abstract Introduction Burnout among healthcare professionals remains a critical public health issue linked to impaired cognition, emotional exhaustion, and diminished clinical performance. Structured breathing practices have demonstrated promise in improving autonomic regulation and cerebral oxygenation, yet their feasibility and acceptability in real-world healthcare settings remain underexplored. Objectives This single-arm pilot feasibility trial aims to evaluate the feasibility, acceptability, and implementation appropriateness of a structured breathing-based intervention for healthcare professionals across community-based Mayo Clinic Health System (MCHS) sites. Secondary objectives include assessing usability and engagement with the mobile breathing platform, while exploratory analyses will examine preliminary signals of change in psychological well-being and cerebral hemodynamics. Methods and Analysis A total of 40 physicians and nurses reporting moderate or greater burnout will be enrolled across four MCHS sites. Participants will complete a four-month structured breathing program delivered primarily online, supported by a mobile application for practice tracking. Assessments will occur at baseline, 2 months, and 4 months, with optional functional near-infrared spectroscopy (fNIRS) measures of cerebral oxygenation collected at baseline and 4 months in a subset. Primary outcomes include (1) recruitment yield, retention, and adherence rates; (2) acceptability and participant satisfaction (survey and qualitative feedback); and (3) implementation appropriateness measured by the Acceptability of Intervention Measure (AIM), Intervention Appropriateness Measure (IAM), and Feasibility of Intervention Measure (FIM). Secondary outcomes assess digital engagement and usability through mobile analytics and the System Usability Scale (SUS). Exploratory outcomes evaluate psychological indicators—burnout, depression, anxiety, perceived stress, sleep, fatigue, professional fulfillment, and resilience—and physiological endpoints (fNIRS). Analyses will be descriptive, summarizing feasibility metrics with 95% confidence intervals. Progression criteria (recruitment ≥75%, retention ≥80%, adherence ≥70%, AIM/IAM/FIM ≥4.0) will determine readiness for a definitive hybrid effectiveness–implementation trial. Ethics and Dissemination The study is approved by the Mayo Clinic Institutional Review Board (IRB # 25-009320). All participants will provide informed consent. Study procedures ensure confidentiality, cultural sensitivity, and participant safety. Data will be securely stored in REDCap and disseminated through peer-reviewed publications and scientific conference ClinicalTrials.gov ID The study has been prospectively registered at ClinicalTrials.gov (Identifier NCT07218458 ). Strengths and Limitations Evaluates a structured breathing-based intervention using both subjective and objective indicators of feasibility, including recruitment, retention, adherence, and implementation appropriateness. Integrates mobile application analytics with standardized implementation measures (AIM, IAM, FIM) to capture digital engagement and real-world usability. Incorporates functional near-infrared spectroscopy (fNIRS) to explore physiological mechanisms underlying burnout recovery, linking cerebral oxygenation to behavioral outcomes. Conducted across diverse community-based Mayo Clinic Health System sites, enhancing ecological validity and relevance to decentralized clinical settings. Limitations include the single-arm, region-restricted design, modest sample size, and reliance on volunteer participants, which constrain generalizability and preclude causal inference; exploratory outcomes are intended to guide future trial refinement.