title: Characterization of the rat oral microbiome and the effects of dietary nitrate.
abstract: The nitrate-nitrite-NO pathway to nitric oxide (NO) production is a symbiotic pathway in mammals that is dependent on nitrate reducing oral commensal bacteria. Studies suggest that by contributing NO to the mammalian host, the oral microbiome helps maintain cardiovascular health. To begin to understand how changes in oral microbiota affect physiological functions such as blood pressure, we have characterized the Wistar rat nitrate reducing oral microbiome. Using 16S rRNA gene sequencing and analysis we compare the native Wistar rat tongue microbiome to that of healthy humans and to that of rats with sodium nitrate and chlorhexidine mouthwash treatments. We demonstrate that the rat tongue microbiome is less diverse than the human tongue microbiome, but that the physiological activity is comparable, as sodium nitrate supplementation significantly lowered diastolic blood pressure in Wistar rats and also lowers blood pressure (diastolic and systolic) in humans. We also show for the first time that sodium nitrate supplementation alters the abundance of specific bacterial species on the tongue. Our results suggest that the changes in oral nitrate reducing bacteria may affect nitric oxide availability and physiological functions such as blood pressure. Understanding individual changes in human oral microbiome may offer novel dietary approaches to restore NO availability and blood pressure.
authors.affiliation: Integrative Molecular and Biomedical Sciences Training Program, Baylor College of Medicine, Houston, TX 77030, USA; Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Embriette R
authors.initials: ER
authors.lastname: Hyde
authors.affiliation: Integrative Molecular and Biomedical Sciences Training Program, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Berkley
authors.initials: B
authors.lastname: Luk
authors.affiliation: Center for Nursing Research, School of Nursing, The University of Texas Health Science Center Houston, Houston, TX 77030, USA.
authors.forename: Stanley
authors.initials: S
authors.lastname: Cron
authors.affiliation: Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Lenka
authors.initials: L
authors.lastname: Kusic
authors.affiliation: Integrative Molecular and Biomedical Sciences Training Program, Baylor College of Medicine, Houston, TX 77030, USA; Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Tyler
authors.initials: T
authors.lastname: McCue
authors.affiliation: Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Tonya
authors.initials: T
authors.lastname: Bauch
authors.affiliation: Department of Microbiology and Molecular Genetics, Medical School, The University of Texas Health Science Center Houston, Houston, TX 77030, USA.
authors.forename: Heidi
authors.initials: H
authors.lastname: Kaplan
authors.affiliation: Department of Periodontics, School of Dentistry, The University of Texas Health Science Center Houston, Houston, TX 77054, USA.
authors.forename: Gena
authors.initials: G
authors.lastname: Tribble
authors.affiliation: Integrative Molecular and Biomedical Sciences Training Program, Baylor College of Medicine, Houston, TX 77030, USA; Alkek Center for Metagenomics and Microbiome Research, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, TX, 77030, USA. Electronic address: jpetrosi@bcm.edu.
authors.forename: Joseph F
authors.initials: JF
authors.lastname: Petrosino
authors.affiliation: Texas Therapeutics Institute, Brown Foundation Institute of Molecular Medicine, The University of Texas Health Science Center Houston, Houston, TX 77030, USA. Electronic address: Nathan.Bryan@uth.tmc.edu.
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Bryan
mesh_terms: D000818:Animals; D004032:Diet; D006801:Humans; D008297:Male; D064307:Microbiota / Q000235:genetics*; D058889:Molecular Typing; D009566:Nitrates / Q000008:administration & dosage / Q000378:metabolism*; D009589:Nitrogen Oxides / Q000097:blood; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017208:Rats, Wistar; D014059:Tongue / Q000382:microbiology*
chemical_list: D009566:Nitrates; D009589:Nitrogen Oxides; D012336:RNA, Ribosomal, 16S; C031618:sodium nitrate
keywords: Denitrification; Nitrate; Nitric oxide; Nitrite; Oral bacteria