Pyrroloquinoline Quinone (PQQ)

PQQ is a relatively large molecule that was first discovered in bacteria, by scientists in 1979. The significance of this molecule wasn’t fully realized until a few years later when researchers found that the PQQ molecule could take part in redox reactions. These reactions are vital to the body for energy generation. Energy is the key, since it is required in carrying out virtually all the functions in a cell including: growth, repair, reproduction, synthesis, breakdown, waste removal and others. If energy isn’t produced rapidly and efficiently then cells die.

How PQQ Functions in the Body

PQQ research was taken up by the Japanese; the mechanism of action was painstakingly worked out and attributed to these redox reactions. Redox reactions are a two way street where both oxidation (gain of oxygen or loss of electrons) and reduction (loss of oxygen or gain of electrons) occur simultaneously. In other words, while one molecule is being oxidized, the second is being reduced. Redox reactions allow cells to do two things at once, while saving considerable amounts of energy rather than performing these reactions separately. Redox reactions are an essential part of cells’ existence, and tens of thousands of these reactions occur at any one time. In this regard, PQQ is detected in various tissues and in bodily fluids such as saliva and tears and breast milk.PQQ acts as a catalyst by speeding up reactions, thus saving cells even more energy. Some researchers have classified this as a co-enzyme and a vital ingredient for cell survival, and thus have pushed for PQQ to be classified as a B vitamin; the jury is still out on the latter request. Nonetheless, researchers and clinicians have come to realize and appreciate the importance of PQQ in various diseases but especially in cognitive health.

PQQ’s Role in Cognitive Health

Researchers realized early on that people who consumed quantities of foods rich in PQQ such as tofu, celery, bell peppers and various fermented foods, had better brain function than people consuming lower quantities. This led scientists to look at the effect of PQQ on memory, learning, and other related cognitive functions. At first they looked at PQQ’s mode of action in animals and then in humans.

The Research on PQQ

Animal studies have shown that PQQ protects nerve cells from damage caused by various toxins, it prevents oxidation of nerve tissue by quenching free radicals that otherwise cause much destruction, it increases the production of nerve growth factor which protects nerve cells and was shown to improve the memory tasks that the animals performed. In addition, it was discovered that PQQ’s effectiveness was enhanced when used in combination with another important molecule called Coenzyme Q10.Recently, two human studies have looked at the PQQ+CoQ10 combination and the effects on memory. The first study of 12 week’s duration and which was a double-blind placebo controlled randomised study in healthy patients, looked at three different supplement groups: (i) 22 patients received 20mg of PQQ, (ii) 24 patients received 20mg of PQQ plus 300mg CoQ10 and, (iii) 23 patients received a placebo. Patients performed various verbal and identification memory tests for the study. Both the PQQ and PQQ+CoQ10 groups performed much better than the placebo group in terms of improved memory scores. However, the PQQ+CoQ10 group was even better than the PQQ group on its own; thus indicating the synergy between the two molecules.A second study published in 2012 showed that when 20mg of PQQ alone was administered for eight weeks, it significantly improved sleep quality and duration, reduced anxiety and fatigue, and improved overall quality of life.PQQ+CoQ10 presents a novel and a safe approach to maintaining healthy brain function in terms of memory and learning.

References

1. Aisen PS, Gauthier S, Ferris S et al “Tramiprosate in mild-to-moderate Alzheimer’s disease- a randomised, double blind, placebo-controlled, multi-centre study” Arch Med Sci. 2011; 1: 102-111

2. Caltagirone C, Ferrannini L, Marchionni N et al “The potential protective effect of Tramiprosate (homotaurine) against Alzheimer disease: a review” Aging Clin. Exp. Res. Sept 5 2012

3. Greenberg S M, Rosand J, Schneider AT et al “A phase 2 study of tramiprosate for cerebral amyloid angiopathy” Alzheimer Dis. Assoc. Discord. 2006; 20: 269-274

4. Koikeda T, NereNo M, and Masuda K et al “Pyrroloquinoline quinone disodium salt improves higher brain function.” Med Consult New Remedies, 2011; 48: 519-527

5. Nakano M, Yamamoto T, Okamura H et al “Effect of pyrroloquinoline quinone(PQQ) on mental status of middle-aged and elderly persons.” FOOD style, 2008; 21 13: 50-53 (Japanese)

6. Nakano M, Takeda H, Yamazaki M et-al “Effects of oral supplementation with pyrroloquinoline quinone on stress, fatigue, and sleep.” Functional foods in health and disease, 2012; 2: 307-324

7. Ohwada K, Takeda H, Yamazaki M et al “Pyrroloquinoline quinone(PQQ) prevents cognitive deficit caused by oxidative stress in rats.” J Clin Biochem Nutri, 2008; 42: 29-34.

8. Saumier D, Duong A, Haine D et al “Domain-specific cognitive effects of tramiprosate in patients with mild to moderate Alzheimer’s disease: ADSS-cog subscale results from the Alphase study” J Nutr Health Aging, 2009; 13: 808-812

9. Zhang Y, Feustel PJ, Kimelberg HK et al “Neuroprotection by pyrroloquinoline quinone (PQQ) in reversible middle cerebral artery occlusion in the adult rat.” Brain Res, 2009; 1094: 200-206.