Over 50 million people worldwide are currently living with dementia-a number projected to rise to 152 million by 2050. Mitochondrial dysfunction in the brains of individuals with Mild Cognitive Impairment (MCI) and Alzheimer's Disease (AD) has gained increasing attention as a potential mechanism and therapeutic target. However, no effective treatment specifically targeting mitochondrial function is currently available. Photobiomodulation (PBM) is an innovative, non-invasive technique that delivers near-infrared light transcranially to the brain. PBM is believed to enhance mitochondrial function-particularly in tissues with high mitochondrial density such as the brain-by reducing oxidative stress and increasing ATP production. It can be safely administered to awake outpatients and does not require general anesthesia or surgical intervention. While preclinical and case studies suggest PBM may be beneficial in AD, the absence of placebo-controlled trials and objective biomarkers has limited understanding of its effectiveness and underlying mechanisms. Objectives: This pilot feasibility study aims to assess cognitive outcomes and neural correlates associated with PBM in individuals with early amnestic MCI (aMCI). Participants who meet eligibility criteria (n = 20) will undergo a 6-week, home-based PBM intervention using the Neuro Rx Gamma device (6 days/week, 20 minutes/session). Clinical and cognitive assessments, blood sample collection, and structural and resting-state functional MRI scans will be conducted at two time points: baseline and post-treatment. These assessments will enable evaluation of PBM's effects on cognition and brain function, with particular focus on mitochondrial-related mechanisms. This study offers a unique opportunity to investigate whether PBM can modulate mitochondrial and neural processes associated with cognitive decline in aMCI.
Intervention: The experimental intervention will be the Vielight Neuro RX Gamma photobiomodulation (PBM) device, which delivers near-infrared light via five light-emitting diodes (LEDs) operating at a wavelength of 810 nm. The LEDs are positioned equidistantly on the scalp and intranasally to target key brain regions. The device generates no significant heat, enabling the use of an indistinguishable sham device for placebo control. All participants will self-administer 20-minute sessions once daily, six days per week, for six weeks. Subjects and/or caregivers will receive training to ensure proper at-home use and will be asked to maintain a treatment diary to monitor adherence. Assessments: Each participant will undergo two in-person visits-at baseline (T0) and post-intervention (week 7; T2)-to complete the following evaluations: Mini-Mental State Examination (MMSE) California Verbal Learning Test - Long Delayed Free Recall (CVLT-LDFR) Trail Making Test A and B (TMT-A, TMT-B) Pittsburgh Sleep Quality Index (PSQI) Mild Behavioral Impairment Checklist (MBI-C) Blood tests: lactate and lactate-to-pyruvate (L/P) ratio Structural and resting-state functional MRI, 1H-MRS, CBF An additional safety check will be conducted at week 1, 3, 5, and at the end of the study (either remotely or in person). Safety Endpoints: Serious adverse events (SAEs), regardless of device causality Device-related adverse events (AEs) Rates of epistaxis (nosebleeds) and nasal infections
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
SINGLE
Enrollment
20
The Neuro RX Gamma device is a portable, wearable, low level light therapy (LLLT) delivery device. The Vielight Neuro RX Gamma delivers a synchronized pulse frequency of 40 Hz from all LED clusters.
The Sham device is indistinguishable from the active device. The sham device will not deliver light for the 20 minutes session duration.
St Michael's Hospital
Toronto, Ontario, Canada
Changes from pre- to post-treatment on mental status and cognitive function assessed by Mini-Mental State Examination (MMSE)
MMSE is a brief 30-point assessment
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on verbal learning and memory assessed by California Verbal Learning Test-II (CVLT-II)
The Composite Score was created by grouping variables into domains and averaging the domains into a single Composite Score for each participant using: CVLT-II - Total Recall Trials 1-5 CVLT-II - d' Hits and False Alarms of recognition Yes/No responses CVLT-II - Percent retained at long delay trial from trial 5 at immediate recall condition
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on processing speed assessed by Trail Making Test (TMT)-part A & B
Trail Making A - Time per correct connection
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on peripheral blood-biomarkers assessed by blood
Blood lactate and lactate/pyruvate ratio will be measured due to their noted relationship with mitochondrial function.
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on plasma biomarkers
markers of neuroinflammation (IL-6, IL-10), neurodegeneration (GFAP, NfL), tau pathology (phosphorylated Tau-217), and synaptic plasticity (Brain-Derived Neurotrophic Factor-BDNF)
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on Neuropsychiatric symptoms (NPS) using MBI-C (Mild Behavioral Impairment Checklist)
The MBI-C is a 34-item instrument and serves as a global and domain-specific NPS measure including early symptom presentations
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on structural MRI (T1-weighted imaging)
Cortical thickness and subcortical volume
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on brain metabolites (PCC)
N-acetylaspartate/creatine, lactate/creatine via single-voxel ¹H-MRS
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on structural MRI (Diffusion tensor imaging - DTI)
fractional anisotropy (FA), and mean diffusivity (MD) measure
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on resting state functional connectivity of the default mode network (DMN) via rs-fMRI
Brain networks functional connectivity
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on Pittsburgh sleep quality index
The measure consists of 19 individual items, creating 7 components that produce one global score
Time frame: Assessed at baseline and post-intervention (week 7)
Changes from pre- to post-treatment on cerebral blood flow (CBF)
CBF using pseudo-continuous arterial spin labeling (PCASL) -with a focus on DMN
Time frame: Assessed at baseline and post-intervention (week 7)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.