Pyrroloquinoline quinone attenuates iNOS gene expression in the injured spinal cord.
Pyrroloquinoline quinone (PQQ) is a naturally occurring redox cofactor that acts as an essential nutrient, antioxidant, and redox modulator. PQQ has been demonstrated to oxidize the redox modulatory site of N-methyl-d-aspartic acid (NMDA) receptors. Such agents are known to be neuroprotective in experimental stroke models. Therefore, we examined the possible ameliorating effect of PQQ on spinal cord injury (SCI) in adult rats. Intraperitoneal administration of PQQ effectively promoted the functional recovery of SCI rats after hemi-transection, which was preceded by the attenuation of the expression of inducible nitric oxide (NO) synthase (iNOS) mRNA in the injury site. NO is involved in the secondary detrimental mechanisms and has been implicated in NMDA receptor-mediated neurotoxicity. In fact, administration of PQQ induced significantly decreased lesion size and increased axon density adjoining the lesion area. These observations suggest that PQQ protects against the secondary damage by reducing iNOS expression following primary physical injury to the spinal cord.
Hirakawa
Akihiro
A
Laboratory of Molecular Biology, Gifu Pharmaceutical University, Mitahora-higashi, 5-6-1, Gifu 502-8585, Japan.
Shimizu
Katsuji
K
Fukumitsu
Hidefumi
H
Furukawa
Shoei
S
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001369:Axons / Q000187:drug effects / Q000473:pathology / Q000502:physiology; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D009043:Motor Activity / Q000187:drug effects; D052247:Nitric Oxide Synthase Type II / Q000235:genetics*; D045542:PQQ Cofactor / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013119:Spinal Cord Injuries / Q000201:enzymology* / Q000473:pathology
D000975:Antioxidants; D045542:PQQ Cofactor; D052247:Nitric Oxide Synthase Type II