CoQ10 Clinical Evidence

Heart Health

Southern Medical Journal
Burke BE, R Neuenschwander, RD Olson. Randomized, double-blind, placebo-controlled trial of coenzyme Q10 in isolated systolic hypertension. 2001 Nov; 94(11):111217.

Topic:
Is CoQ10 a safe and effective treatment for hypertension?

Background:
Hypertension is widespread, affecting more than 50 million adults, and is a common risk factor for heart disease.

Study Type:
Human clinical intervention trial

Study Design:
Double-blind, placebo-controlled. Subjects took CoQ10 or a placebo. Blood samples and blood pressure readings were taken.

Dosage:
60 mg/twice daily for 12 weeks

Subjects:
46 men and 37 women with isolated systolic hypertension (meaning the maximum, or top number, is elevated while the minimum, or bottom number, is not)

Results:
Systolic blood pressure was reduced by an average of 17.8 ± 7.3 mm Hg.

Conclusions:
“Our results suggest CoQ10 may be safely offered to hypertensive patients as an alternative option.”

Journal of Human Hypertension
Singh RB et al. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. 1999 Mar; 13(3):203–8.

Topic:
What is the effect of CoQ10 on blood pressure and insulin resistance in subjects with hypertension and coronary artery disease?

Background:
Heart disease and insulin resistance seem to be intertwined, with insulin-resistant patients suffering higher rates of heart failure. Is there a treatment that can address both issues?

Study Type:
Human clinical intervention trial

Study Design:
Randomized, double-blind. Subjects took either CoQ10 or vitamin B. After 8 weeks, researchers recorded their blood pressure, insulin levels (fasting and 2 hours after eating), blood sugar, triglycerides, and several markers of oxidative stress.

Dosage:
60 mg/twice daily for 8 weeks

Subjects:
59 patients taking blood pressure medication

Results:
In the treatment group, HDL (good) cholesterol and antioxidants such as vitamins A, C, E, and beta-carotene all rose. In the vitamin B group, only vitamin C and beta-carotene rose.

Conclusions:
“These findings indicate that treatment with coenzyme Q10 decreases blood pressure, possibly by decreasing oxidative stress and insulin response in patients with known hypertension receiving conventional antihypertensive drugs.”

Molecular Aspects of Medicine
Digiesi V et al. Coenzyme Q10 in essential hypertension. 1994; 15 Suppl:s257–63.

Topic:
What is the effect of CoQ10 on blood pressure and cholesterol levels?

Background:
Blood pressure and cholesterol levels are both well-known risk factors for cardiovascular disease.

Study Type:
Human clinical intervention trial

Study Design:
Subjects took CoQ10. Researchers measured blood levels of CoQ10, total and HDL (good) cholesterol, and blood pressure at baseline and at 10 weeks.

Dosage:
50 mg/twice daily for 10 weeks

Subjects:
26 patients with high blood pressure

Results:
Over the course of the study, CoQ10 levels rose with supplementation. Systolic blood pressure (the upper reading) decreased from 164.5 ± 3.1 to 146.7 ± 4.1 mm Hg and diastolic blood pressure (the lower reading) decreased from 98.1 ± 1.7 to 86.1 ± 1.3 mm Hg. Total cholesterol fell and HDL cholesterol rose{cke_protected_1}[MT1]{cke_protected_2}.

Mechanism of Action
CoQ10 improves heart health by dilating blood vessels, inhibiting LDL oxidation (slowing the progression of atherosclerosis), decreasing inflammatory cytokines, and decreasing blood viscosity. CoQ10 is also an antioxidant that inhibits superoxide, a free radical, either by scavenging it, or by interfering with its synthesis in blood vessels and vascular muscle. MicroActive® CoQ10 is 3 times better absorbed than standard CoQ10 because it is encapsulated in a molecular carrier of beta-cyclodextrin, a compound made of sugar molecules that increases the solubility of CoQ10.

Circulation
Damian MS, et al. Coenzyme Q10 combined with mild hypothermia after cardiac arrest: a preliminary study. 2004 Nov 9;110(19):3011-6.

Topic:
Can therapeutic hypothermia combined with CoQ10 increase survival rate and protect against neurodegenerative disorders after a heart attack?

Background:
Inducing mild hypothermia in patients who have suffered cardiac arrest and undergone CPR can improve survival rates. CoQ10 has been shown to protect patients with neurodegenerative disorders. How might they work together?

Study Type:
Human clinical intervention trial

Study Design:
Randomized, placebo-controlled design. Subjects’ core temperatures were lowered to 35 degrees C˚ for 24 hours after CPR, and they were then administered either CoQ10 or a placebo for 5 days.

Subjects:
49 subjects who had received CPR

Dosage:
250 mg, followed by 150 mg/3 times a day for 5 days

Results:
Survival rates 3 months after cardiac arrest were 68% for the CoQ10 group compared to 29% for the placebo group — more than double. In those taking CoQ10, 9 of the survivors had a Glasgow Outcome Scale of 4 or 5 (indicating moderate disability or good recovery), while only 5 of the placebo group did. The treatment group also had significantly lower mean serum S100 protein 24 hours after CPR. (Serum S100 is a marker of brain damage during a heart attack.)

Conclusion:
Combining CoQ10 with mild hypothermia immediately after CPR appears to improve survival and may improve neurological outcome in survivors.

The Journal of Thoracic and Cardiovascular Surgery
Rosenfeldt F, et al. Coenzyme Q10 therapy before cardiac surgery improves mitochondrial function and in vitro contractility of myocardial tissue. 2005 Jan;129(1):25-32.

Topic:
What are the effects of CoQ10 given before cardiac surgery?

Background:
Previous studies have suggested that CoQ10 given before surgery may protect the myocardial (or muscular) tissues of the heart. One possible mode of action is by improving mitochondrial function. What effect does CoQ10 have on the mitochondria, and can it help patients recover from heart surgery?

Study Type:
Human clinical intervention trial

Study Design::
Randomized, placebo-controlled. Subjects took either CoQ10 or a placebo for 2 weeks before surgery. Mitochondria from the subjects’ hearts were isolated and studied in vitro. Subjects’ cardiac function after surgery was also studied.

Subjects:
121 patients scheduled for elective cardiac surgery

Dosage:
300 mg/day for 2 weeks

Results:
Mitochondria taken from the treatment group were found to have more respiratory efficiency than mitochondria taken from the control group. When submitted to hypoxia (oxygen deprivation), the mitochondria from the treatment group recovered with greater force. There was no difference between the groups in either blood circulation or in the release of troponin (a group of proteins that regulate the contractions of cardiac muscles).

Conclusion:
Preoperative oral coenzyme Q(10) therapy in patients undergoing cardiac surgery increases myocardial and cardiac mitochondrial coenzyme Q(10) levels, improves mitochondrial efficiency, and increases myocardial tolerance to in vitro hypoxia-reoxygenation stress.

Clinical Cardiology
Berman M, et al. Coenzyme Q10 in patients with end-stage heart failure awaiting cardiac transplantation: a randomized, placebo-controlled study. 2004 May;27(5):295-9.

Topic:
Can CoQ10 help patients with end-stage heart failure as they wait for heart transplants?

Background:
Previous studies have shown CoQ10 can benefit heart patients. What are its effects on patients during the risky period just before a heart transplant?

Study Type:
Human clinical intervention trial. Subjects took CoQ10 or placebo while continuing their regular medication. They were assessed using a questionnaire, a 6-minute walking test, blood tests and echocardiography.

Study Design:
Randomized, double-blind placebo-controlled design.

Subjects:
32 patients with end-stage heart failure (27 completed)

Dosage:
60 mg CoQ10/day for 3 months

Results:
Patients in the treatment group showed significant improvement on the walking test and a decrease in shortness of breath, fatigue and waking to urinate at night. Their scores on the New York Heart Association classification also improved. No improvements were noted in blood tests or echocardiography.

Conclusion:
The administration of CoQ10 to heart transplant candidates led to a significant improvement in functional status, clinical symptoms, and quality of life…Coenzyme Q10 may serve as an optional addition to the pharmacologic armamentarium of patients with end-stage heart failure.

Cognitive and anti-aging

Cellular and Molecular Biology
Barbiroli B, et al. Coenzyme Q10 improves mitochondrial respiration in patients with mitochondrial cytopathies. An in vivo study on brain and skeletal muscle by phosphorus magnetic resonance spectroscopy. 1997 Jul;43(5):741-9.

Topic:
How does CoQ10 effect the efficiency of mitochondrial respiration in the brain and skeletal muscles of patients with mitochondrial cytopathy?

Background:
CoQ10 helps the mitochondria manufacture energy in the form of ATP. Can supplementation with CoQ10 help patients with mitochondrial pathologies?

Study Type:
Human clinical intervention trial

Study Design::
Researchers used phosphorus magnetic resonance spectroscopy to study the effects of CoQ10 supplementation in the brains and skeletal muscles of the subjects.

Subjects:
6 patients with different mitochondrial pathologies

Dosage:
150 mg/day for 6 months

Results:
Before treatment, the subjects had low levels of phosphocreatine (reserves of high-energy phosphorus found in the brain and the skeletal muscles), abnormally high levels of ATP synthesis, and low cytosolic phosphorylation potential (i.e. low energy within cells). After treatment, all patients improved in all variables measured, returning to normal ranges.

Conclusion:
After a six-month treatment with 150 mg CoQ10/day all brain variables were remarkably improved in all patients, returning within the control range in all cases. Treatment with CoQ10 also improved the muscle mitochondrial functionality enough to reduce the average deficit to 56% of the control group.

Archives of Neurology
Shults CW, et al. Effects of coenzyme Q10 in early Parkinson disease: evidence of slowing of the functional decline. 2002 Oct;59(10):1541-50.

Topic:
Is CoQ10 a safe and effective treatment to slow the decline of patients with Parkinson Disease?

Background:
Parkinson Disease (PD) is a degenerative neurological disease. No treatment has been found to slow its progression.

Study Type:
Human intervention trial

Study Design:
Multi-center, randomized, parallel group, double-blind, placebo-controlled, dosage ranging trial. Subjects were evaluated using the Unified Parkinson Disease Rating Scale (UPDRS) at screening, baseline and 1, 4, 8, 12 and 16 months after baseline. Each patient was followed for 16 months or until he or she became disabled enough to require treatment with levodopa (a drug used to treat PD).

Subjects:
80 subjects in the early stages of PD who did not yet require treatment

Dosage:
300, 600 or 1,200 mg/day for up to 16 months

Results:
CoQ10 was safe and well-tolerated at all 3 doses. The UPDRS adjusted mean score rose in the placebo group by 11.99 (a higher score indicates more disability). In the 300 mg group, the score rose by 8.81, in the 600 mg group by 10.82 and in the 1,200 mg group by only 6.69.

Conclusion:
Less disability developed in subjects assigned to Coenzyme Q10 than in those assigned to placebo, and the benefit was greatest in subjects receiving the highest dose. Coenzyme Q10 appears to slow the progressive deterioration of function in PD, but these results need to be confirmed in a larger study.

Movement Disorders
Stamelou M, et al. Short-term effects of coenzyme Q10 in progressive supranuclear palsy: a randomized, placebo-controlled trial. 2008 May 15;23(7):942-9.

Topic:
What are the short-term effects of CoQ10 on patients with progressive supranuclear palsy (PSP)?

Background:
An electron transport chain is a method by which chemical energy is generated in the brain. One part of the electron transport chain, mitochondrial complex 1, is dysfunctional in patients with PSP. Since naturally occurring CoQ10 in the brain is part of this transfer chain, can supplementing with CoQ10 help patients with PSP?

Study Type:
Human clinical intervention trial

Study Design:
Double-blind, randomized, placebo-controlled, phase II trial

Subjects:
21 clinically probable PSP patients, stage 3 or lower

Dosage:
5mg/kg/day for 6 weeks, e.g. 340mg for a 150-lb person.

Results:
CoQ10 was safe and well tolerated. In subjects taking CoQ10 (compared to the placebo group), the ratio of high-energy phosphates to low-energy phosphates increased. (High-energy phosphates store the energy used in metabolic processes.) Changes were significant in the occipital lobe and consistent in the basal ganglia. Overall, subjects in the treatment group improved slightly but significantly on the PSP rating scale and the Frontal Assessment Battery.

Conclusion:
Since CoQ10 appears improve cerebral energy metabolism in PSP, long-term treatment might have a disease-modifying, neuroprotective effect.

CoQ10 Mechanism of Action:

Like PQQ, CoQ10 also improves memory, spatial awareness, and attention span. It is one of the enzymes in the electron transport chain, which generates chemical energy within the mitochondria of cells. When CoQ10 is supplemented to higher levels in the diet, it increases cellular energy production, which may result in more energy being available for cognitive processes.

As an antioxidant, CoQ10 protects mitochondria in nerve cells from damage due to free radicals, whose numbers increase with age. It also increases their ability to produce energy during adverse conditions. Improved mitochondria energy output helps cells to function more efficiently as they age, slows the decline of cellular energy, and leads to improved cell survival and function.

The increased synthesis of mitochondria is caused by the activation of two proteins that regulate the expression of genes and the formation of mitochondria: cAMP response element-binding protein (CREB) and peroxisome proliferator-activated receptor-coactivator-1 (PGC-1).

Athletic Performance

Journal of Strength and Conditioning Research
Gokbel H, et al. The effects of coenzyme Q10 supplementation on performance during repeated bouts of supramaximal exercise in sedentary men. 2010 Jan:24(1):97-102.

Topic:
What are the effects of CoQ10 supplementation on athletic performance during supramaximal exercise?

Background:
Supramaximal exercise is exercise so intense that it requires energy production beyond the body’s maximum aerobic capacity and therefore requires energy from anaerobic metabolism. Can CoQ10 help produce the necessary energy for supramaximal exercise?

Study Type:
Human clinical intervention trial

Study Design::
Randomized, double-blind crossover study

Subjects:
15 healthy sedentary men

Dosage:
Two 8-week periods of either 100 mg CoQ10 per day or placebo

Results:
Subjects performed 5 Wingate tests (a measure of short-term athletic power on a stationary bicycle) at baseline and after supplementation. Researchers measured peak power, mean power and fatigue. Over the course of the tests, peak power and mean power fell for both the treatment and the control groups, and fatigue increased. However, in the last test, mean power rose only in the CoQ10 group.

Conclusion:
CoQ10 may show performance-enhancing effects during the repeated bouts of supramaximal exercises and CoQ10 might be used as an ergogenic [performance-enhancing] aid.

Nutrition
Mizuno K, et al. Antifatigue effects of coenzyme Q10 during physical fatigue. 2008 Apr;24(4):293-9.

Topic:
Mizuno K, et al. Antifatigue effects of coenzyme Q10 during physical fatigue. 2008 Apr;24(4):293-9.

Background:
The body uses CoQ10 to generate 90-95% of its energy. Can it alleviate fatigue during exercise?

Study Type:
Human clinical intervention trial

Study Design::
Randomized, double-blind, placebo-controlled, three crossover design. Subjects took CQ10 or a placebo for 8 days. They performed workload trials on a stationary bicycle at fixed workloads twice for two hours and rested for four hours. Subjects’ maximum velocity for a 10-second sprint was tested at 30 minutes and 210 minutes from the start of physical tasks.

Subjects:
17 healthy volunteers

Dosage:
100 or 300 mg/day for 8 days

Results:
Subjects in the 300 mg treatment group had a greater increase in maximum velocity during exercise than subjects in the control group. Members of this treatment group also experienced less fatigue, as measured by the visual analog scale, than those in the control group.

Conclusion:
Oral administration of coenzyme Q10 improved subjective fatigue sensation and physical performance during fatigue-inducing workload trials and might prevent unfavorable conditions as a result of physical fatigue.

Clinical Therapy
Satta A, et al. Effects of ubidecarenone in an exercise training program for patients with chronic obstructive pulmonary diseases. 1991 Nov-Dec;13(6):754-7.

Topic:
What is the effect of CoQ10 on patients with chronic obstructive pulmonary disease (COPD) undergoing pulmonary rehabilitation?

Background:
COPD is one of the most common lung diseases. It occurs in patients who have both chronic bronchitis and emphysema and causes shortness of breath. COPD is a progressive disease associated with smoking.

Study Type:
Human clinical intervention trial.

Study Design:
Patients exercised before and after taking CoQ10. Oxygen consumption, volume of breath expired and heart rate were measured both times.

Subjects:
20 patients with COPD who had been exercising for at least 4 weeks prior to the experiment

Dosage:
50 mg/day

Results:
In the treatment (CoQ10) group, maximum oxygen consumption increased 13%, as compared to 7% in the control group. The increase was significant only in the treatment group. There were no differences in heart rate between the two groups.

Conclusion:
[U]bidecarenone [CoQ10] deserves further evaluation in exercise training programs for patients with COPD.

American Journal of Cardiology
Kamikawa T, et al. Effects of coenzyme Q10 on exercise tolerance in chronic stable angina pectoris. 1985 Aug 1;56(4):247-51.

Topic:
What are the effects of CoQ10 on exercise performance in patients with angina pectoris?

Background:
Angina pectoris is severe chest pain due to a lack of blood (and therefore oxygen) in the heart muscle caused by obstruction or spasms in the coronary arteries.

Study Type:
Human clinical intervention trial.

Study Design::
Double blind, placebo-controlled, randomized, crossover protocol.

Subjects:
12 patients with stable angina pectoris and an average age of 56

Dosage:
150 mg/day in three doses per day for 4 weeks

Results:
Patients taking CoQ10 experienced less chest pain and consumed less nitroglycerin than those in the control group, but these differences were not statistically significant. However, there were significant increases in exercise time and in time until an ST-depression (an electrocardiogram reading that indicates a restriction of blood flow to the heart) occurred during exercise. Members of the treatment group also had higher concentrations of CoQ10 in their blood and this increase correlated with the increase in exercise duration.

Conclusion:
This study suggests that CoQ10 is a safe and promising treatment for angina pectoris.