Pyrroloquinoline quinone preserves mitochondrial function and prevents oxidative injury in adult rat cardiac myocytes.
We investigated the ability of pyrroloquinoline quinone (PQQ) to confer resistance to acute oxidative stress in freshly isolated adult male rat cardiomyocytes. Fluorescence microscopy was used to detect generation of reactive oxygen species (ROS) and mitochondrial membrane potential (Deltapsi(m)) depolarization induced by hydrogen peroxide. H(2)O(2) caused substantial cell death, which was significantly reduced by preincubation with PQQ. H(2)O(2) also caused an increase in cellular ROS levels as detected by the fluorescent indicators CM-H2XRos and dihydroethidium. ROS levels were significantly reduced by a superoxide dismutase mimetic Mn (III) tetrakis (4-benzoic acid) porphyrin chloride (MnTBAP) or by PQQ treatment. Cyclosporine-A, which inhibits mitochondrial permeability transition, prevented H(2)O(2)-induced Deltapsi(m) depolarization, as did PQQ and MnTBAP. Our results provide direct evidence that PQQ reduces oxidative stress, mitochondrial dysfunction, and cell death in isolated adult rat cardiomyocytes. These findings provide new insight into the mechanisms of PQQ action in the heart.
Tao
Rong
R
Cardiology Section, San Francisco VA Medical Center and UCSF, San Francisco, CA, USA.
Karliner
Joel S
JS
Simonis
Ursula
U
Zheng
Jie
J
Zhang
Jianqing
J
Honbo
Norman
N
Alano
Conrad C
CC
D000818:Animals; D002478:Cells, Cultured; D019610:Cytoprotection / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D008297:Male; D008929:Mitochondria, Heart / Q000187:drug effects / Q000502:physiology*; D032383:Myocytes, Cardiac / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology*; D045542:PQQ Cofactor / Q000008:administration & dosage / Q000502:physiology*; D051381:Rats; D017382:Reactive Oxygen Species / Q000378:metabolism*
D017382:Reactive Oxygen Species; D045542:PQQ Cofactor