Effects of pyrroloquinoline quinone on noise-induced and age-related hearing loss in mice

Abstract

We investigated whether the oxidoreductase cofactor pyrroloquinoline quinone (PQQ) prevents noise-induced and age-related hearing loss (NIHL and ARHL) in mice. To assess NIHL, 8 week-old mice with and without PQQ administration were exposed to noise for 4 h. PQQ was orally administered for one week before and after noise exposure and subcutaneously once before noise exposure. For ARHL evaluation, mice were given drinking water with or without PQQ starting at 2 months of age. In the NIHL model, PQQ-treated mice had auditory brainstem response (ABR) thresholds of significantly reduced elevation at 8 kHz, a significantly increased number of hair cells at the basal turn, and significantly better maintained synapses beneath the inner hair cells compared to controls. In the ARHL model, PQQ significantly attenuated the age-related increase in ABR thresholds at 8 and 32 kHz at 10 months of age compared to controls. In addition, the hair cells, spiral ganglion cells, ribbon synapses, stria vascularis and nerve fibers were all significantly better maintained in PQQ-treated animals compared to controls at 10 months of age. These physiological and histological results demonstrate that PQQ protects the auditory system from NIHL and ARHL in mice.

Dietary pyrroloquinoline quinone hinders aging progression in male mice and D-galactose-induced cells

“…Research has shown that PQQ improves cognitive brain function for memory learning ability in aged mice ( Yamada et al, 2020 ) and for composite and verbal memory in older adults ( Tamakoshi et al, 2023 ). Additionally, other studies in mice have demonstrated that the antioxidant effects of PQQ ameliorate age-related hearing loss ( Gao et al, 2022 ), prevent estrogen deficiency-induced osteoporosis ( Geng et al, 2019 ), and protect against skin aging ( Li et al, 2022 ).…”

The effects of pyrroloquinoline quinone disodium salt on brain function and physiological processes

“…In addition to promoting brain functions, PQQ has an inhibitory effect on fat accumulation during high-fat diet consumption in animal studies (44,45), and PQQ was shown to improve hearing loss (46) and extend lifespan (47). Therefore, it may be effective in improving fat metabolism and fighting age-related disorders.…”