Effects of Ubiquinol and Ubiquinone on Vascular Function in Healthy Adults With Borderline High LDL-Cholesterol

This randomized, double-blind, placebo-controlled clinical trial will evaluate the effects of Ubiquinol and Ubiquinone on vascular endothelial function in generally healthy adults with borderline high LDL-cholesterol. Participants will receive Ubiquinol 200 mg/day, Ubiquinone 200 mg/day, or placebo for 8 weeks. The primary outcome is change in flow-mediated dilation (FMD), a measure of vascular endothelial function, assessed at baseline, Week 4, and Week 8. The study will also evaluate changes in plasma CoQ10 levels, nitric oxide, LDL oxidation susceptibility, oxidative stress markers, and treatment-emergent adverse events.

Inclusion Criteria: * Males aged 35-65 with BMI 18.5-29.9 kg/m². * Post-menopausal females up to age 65 with BMI 18.5-29.9 kg/m². * Generally healthy individuals with mild cardiovascular risk factors, specifically -borderline high LDL-C between 100 and 159 mg/dL. * No current acute or uncontrolled chronic illness. * Screening FMD: 2.5-6.0%. Exclusion Criteria: * Having been diagnosed with known allergies to any ingredients in the product. * Relevant history or presence of any medical disorder potentially interfering with this study, including but not limited to malabsorption, significant gastrointestinal diseases (e.g., severe constipation, diarrhea, inflammatory bowel disease such as Crohn's disease or ulcerative colitis), severe psychiatric illness which in the opinion of the investigator would interfere with optimal participation in the study, and known cardiovascular disease or stroke, except for conditions deemed clinically insignificant by the investigator (e.g., clinically insignificant atherosclerotic lesions observed by imaging studies). * Smokers \>10 cigarettes per day. * Subjects consuming \>2 alcoholic units per day. * Subjects reporting a change \>5% in body weight within 1 month prior to Screening Visit. * Subjects playing competitive or high-intensity physical activity. * Subjects using lipid-altering drug therapy or supplements, nitric oxide donors, phosphodiesterase inhibitors, high-dose antioxidant supplements (including vitamin C), flavonoid-enriched products, or Ubiquinol/Ubiquinone supplements within 4 weeks prior to Screening Visit. * Having a history of cancer within the past 5 years. * Having a history of immunosuppression/immune deficiency disorders, including HIV infection, AIDS, multiple sclerosis, Crohn's disease, rheumatoid arthritis, organ transplant, or currently using oral or systemic immunosuppressive medications and biologics and/or undergoing radiation or chemotherapy. * Currently using or having regularly used corticosteroids (systemic or topical, not nasal or ocular) within the past 4 weeks. * Having diseases such as asthma, diabetes, epilepsy, hypertension, hyperthyroidism, or hypothyroidism that are not controlled by diet or medication. * Individuals having multiple health conditions may be excluded from participation even if the conditions are controlled by diet, medication, etc. * Having started a long-term medication within the last 2 months. * Having planned surgeries or invasive medical procedures during the study. * Noninvasive medical procedures or surgeries will be reviewed for their impact on the study outcome and acceptability by the Investigator or designee. * Currently participating in any other clinical trial at SFRI or another research facility or doctor's office.