Gastroprotective and blood pressure lowering effects of dietary nitrate are abolished by an antiseptic mouthwash.
Recently, it has been suggested that the supposedly inert nitrite anion is reduced in vivo to form bioactive nitric oxide with physiological and therapeutic implications in the gastrointestinal and cardiovascular systems. Intake of nitrate-rich food such as vegetables results in increased levels of circulating nitrite in a process suggested to involve nitrate-reducing bacteria in the oral cavity. Here we investigated the importance of the oral microflora and dietary nitrate in regulation of gastric mucosal defense and blood pressure. Rats were treated twice daily with a commercial antiseptic mouthwash while they were given nitrate-supplemented drinking water. The mouthwash greatly reduced the number of nitrate-reducing oral bacteria and as a consequence, nitrate-induced increases in gastric NO and circulating nitrite levels were markedly reduced. With the mouthwash the observed nitrate-induced increase in gastric mucus thickness was attenuated and the gastroprotective effect against an ulcerogenic compound was lost. Furthermore, the decrease in systemic blood pressure seen during nitrate supplementation was now absent. These results suggest that oral symbiotic bacteria modulate gastrointestinal and cardiovascular function via bioactivation of salivary nitrate. Excessive use of antiseptic mouthwashes may attenuate the bioactivity of dietary nitrate.
Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden. Joel.Petersson@mcb.uu.se
Joel
J
Petersson
Mattias
M
Carlström
Olof
O
Schreiber
Mia
M
Phillipson
Gustaf
G
Christoffersson
Annika
A
Jägare
Stefan
S
Roos
Emmelie A
EA
Jansson
A Erik G
AE
Persson
Jon O
JO
Lundberg
Lena
L
Holm
D000284:Administration, Oral; D000818:Animals; D000891:Anti-Infective Agents, Local / Q000008:administration & dosage*; D001794:Blood Pressure / Q000187:drug effects*; D002710:Chlorhexidine / Q000008:administration & dosage*; D019610:Cytoprotection; D004032:Diet; D005247:Feeding Behavior; D005753:Gastric Mucosa / Q000737:chemistry / Q000378:metabolism*; D008297:Male; D009067:Mouthwashes / Q000008:administration & dosage*; D009566:Nitrates / Q000008:administration & dosage / Q000378:metabolism*; D009569:Nitric Oxide / Q000032:analysis; D009573:Nitrites / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D000891:Anti-Infective Agents, Local; D009067:Mouthwashes; D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; D002710:Chlorhexidine