Effects of Antioxidant Supplements (BioPQQ™) on Cerebral Blood Flow and Oxygen Metabolism in the Prefrontal Cortex
Pyrroloquinoline quinone (PQQ) is a quinone compound originally identified in methanol-utilizing bacteria and is a cofactor for redox enzymes. At the Meeting of the International Society on Oxygen Transport to Tissue (ISOTT) 2014, we reported that PQQ disodium salt (BioPQQ™) improved cognitive function in humans, as assessed by the Stroop test. However, the physiological mechanism of PQQ remains unclear. In the present study, we measured regional cerebral blood flow (rCBF) and oxygen metabolism in prefrontal cortex (PFC), before and after administration of PQQ, using time-resolved near-infrared spectroscopy (tNIRS). A total of 20 healthy subjects between 50 and 70 years of age were administered BioPQQ™ (20 mg) or placebo orally once daily for 12 weeks. Hemoglobin (Hb) concentration and absolute tissue oxygen saturation (SO2) in the bilateral PFC were evaluated under resting conditions using tNIRS. We found that baseline concentrations of hemoglobin and total hemoglobin in the right PFC significantly increased after administration of PQQ (p < 0.05). In addition, decreases in SO2 level in the PFC were more pronounced in the PQQ group than in the placebo group (p < 0.05). These results suggest that PQQ causes increased activity in the right PFC associated with increases in rCBF and oxygen metabolism, resulting in enhanced cognitive function.
KeywordsNIRS Prefrontal cortex Pyrroloquinoline quinone Stroop test Working memory
This research was supported in part by the Strategic Research Foundation Grant-aided Project for Private Universities (S1411017) and a Grant-in-Aid for Exploratory Research (25560356) from the Ministry of Education, Culture, Sports, Sciences, and Technology of Japan. Furthermore, this research was supported through grants from Iing Co., Ltd. (Tokyo, Japan), Alpha Electron Co., Ltd. (Fukushima, Japan), NJI Co., Ltd. (Fukushima, Japan), and Southern Tohoku General Hospital (Fukushima, Japan).
- 12.Itoh Y, Hine K, Miura H et al (in press) Effect of the antioxidant supplement pyrroloquinoline quinone disodium salt (BioPQQTM) on cognitive functions. Adv Exp Med Biol 876:319–326Google Scholar
- 16.Nakano M, Yamamoto T, Okumura H et al (2012) Effects of oral supplementation with pyrroloquinoline quinone on stress, fatigue, and sleep. Funct Foods Health Dis 2:307–324Google Scholar