No effect of pyrroloquinoline quinone on mouse body weight and energy metabolism with the concomitant increase in mitochondrial biogenesis and antioxidant ability

Pyrroloquinoline quinone (PQQ) stimulates mitochondrial biogenesis and exhibits antioxidant properties. Since mitochondria play a crucial role in energy generation and metabolism, the present study aims to clarify whether PQQ is able to modulate energy expenditure and the development of obesity by regulating mitochondrial biogenesis. Male mice fed normal chow diet (NCD) or high fat diet (HFD) were supplemented with PQQ through drinking water for three months. Throughout this period, food and water intake, body weight, energy metabolic rate and the autonomous activity of the mice were measured. Then, the mice were sacrificed and the tissues were collected. Mitochondrial biogenesis, antioxidant capacity, and changes in gene expression were measured in liver tissue. The results showed that PQQ supplementation did not result in significant alterations in the food and water intake, body weight, and energy metabolic rate of the mice fed NCD or HFD although it significantly enhanced mitochondrial biogenesis and antioxidant capabilities of liver and promoted autonomous activity in NCD mice. Moreover, it had no impact on the adipose tissue mass in mice fed NCD or HFD. While PQQ supplementation induced the changes in metabolism-related genes such as CPT1a, SCD1, FABP1, HK2, HK3 and PGK1 in liver, it is suggested PQQ supplementation may influence lipid and glucose metabolism. However, PQQ-induced changes in hepatic gene expression and mitochondrial biogenesis are unable to alter systemic energy metabolism and adipose tissue accumulation in male mice.