Concurrent administration of coenzyme Q10 and alpha-tocopherol
improves learning in aged mice.
McDonald SR, Sohal RS, Forster MJ.

Department of Pharmacology and Neuroscience, Institute for Aging and
Alzheimer's Disease Research, University of North Texas Health Science
Center at Fort Worth, Fort Worth, TX 76107, USA.

The main purpose of this study was to determine whether supplemental
intake of coenzyme Q10 (CoQ) (ubiquinone-10) or alpha-tocopherol,
either alone or together, could improve brain function of aged mice,
as reflected in their cognitive or psychomotor performance. Separate
groups of aged mice (24 months) were administered either CoQ (123 mg/
kg/day), or alpha-tocopherol acetate (200 mg/kg/day), or both, or the
vehicle (soybean oil) via gavage for a period of 14 weeks. Three weeks
following the initiation of these treatments, mice were given a
battery of age-sensitive behavioral tests for the assessment of
learning, recent memory, and psychomotor function. In a test that
required the mice to rapidly identify and remember the correct arm of
a T-maze, and to respond preemptively in order to avoid an electric
shock, the intake of alpha-tocopherol plus CoQ resulted in more rapid
learning compared to the control group. Learning was not significantly
improved in the mice receiving CoQ or alpha-tocopherol alone. None of
the treatments resulted in a significant improvement of psychomotor
performance in the old mice. In a separate study, treatment with
higher doses of CoQ alone (250 or 500 mg/kg/day) for 14 weeks failed
to produce effects comparable to those of the combination of alpha-
tocopherol and CoQ. The apparent interaction of CoQ and alpha-
tocopherol treatments is consistent with the previous suggestion,
based on biochemical studies, that coenzyme Q and alpha-tocopherol act
in concert. Overall, the findings suggest that concurrent
supplementation of alpha-tocopherol with CoQ is more likely to be
effective as a potential treatment for age-related learning deficits
than supplementation with CoQ or alpha-tocopherol alone.