Causal Effect of Coenzyme Q10 Nutrition and Cognitive Dysfunction in the Metabolic Storm (Hyperglycemia and Sarcopenia) and Brain-derived Neurotrophic Factor

Mild cognitive impairment (MCI) and Alzheimer's disease (AD) are associated with impaired glucose and energy metabolism, oxidative stress, and nutritional imbalance. Coenzyme Q10 is an antioxidant nutrient involved in mitochondrial energy production and may have beneficial effects on glucose metabolism and muscle function. This randomized, double-blind, placebo-controlled crossover study investigated the effects of coenzyme Q10 supplementation in participants with MCI or AD and hyperglycemia, either without sarcopenia risk or with pre-sarcopenia/sarcopenia risk. Participants received coenzyme Q10 300 mg/day (150 mg twice daily) or placebo for 12 weeks, followed by a 4-week washout period and crossover to the alternate intervention for another 12 weeks. Anthropometric measurements, nutritional status, body composition, muscle function, cognitive function, quality of life, and depressive symptoms were assessed. Blood samples were collected to evaluate coenzyme Q10, glucose metabolism, BDNF, oxidative stress, antioxidant capacity, myokines, and mitochondrial function. The study aimed to evaluate the effects of coenzyme Q10 supplementation on glucose metabolism, muscle and physical function, and related metabolic and neurotrophic factors in participants with cognitive impairment and hyperglycemia.

Inclusion criteria

• Clinical diagnosis of mild cognitive impairment (MCI) or Alzheimer's disease (AD).
• Hyperglycemia, defined as fasting plasma glucose ≥100 mg/dL or current use of glucose-lowering medication.
• Either without sarcopenia risk or with pre-sarcopenia/sarcopenia risk, as determined by calf circumference, handgrip strength, or muscle endurance.
• Ability to swallow tablets.

Exclusion criteria

• Cancer.
• Severe cardiac, pulmonary, hepatic, or renal disease.
• Severe disability or aphasia.
• Malnutrition (body weight change >5% within one month).
• Current use of coenzyme Q10 supplements.
• Current warfarin therapy.