title: Correlation between Saliva and Plasma Levels of Endothelin Isoforms ET-1, ET-2, and ET-3.
abstract: Although saliva endothelins are emerging as valuable noninvasive cardiovascular biomarkers, reports on the relationship between isoforms in saliva and plasma remain scarce. We measured endothelins in concurrent saliva and plasma samples (n = 30 males; age 18-63) by HPLC-fluorescence. Results revealed statistically significant positive correlations among all isoforms between saliva and plasma: big endothelin-1 (BET-1, 0.55 ± 0.27 versus 3.35 ± 1.28 pmol/mL; r = 0.38, p = 0.041), endothelin-1 (ET-1, 0.52 ± 0.21 versus 3.45 ± 1.28 pmol/mL; r = 0.53, p = 0.003), endothelin-2 (ET-2, 0.21 ± 0.07 versus 1.63 ± 0.66 pmol/mL; r = 0.51, p = 0.004), and endothelin-3 (ET-3, 0.39 ± 0.19 versus 2.32 ± 1.44 pmol/mL; r = 0.75, p < 0.001). Correlations of BET-1, ET-1, and ET-3 within each compartment were positive in both plasma (p < 0.05) and saliva (p ≤ 0.1), whereas ET-2 was not significantly correlated with other isoforms in either plasma or saliva. For all isoforms, concentrations varied on average fivefold between individuals (90th/10th percentiles); individuals with high plasma endothelin levels generally had high saliva endothelin levels. Our results reveal that salivary ET isoform profiles portray the plasmatic profiles and support the view of coordinated regulation of ET-1 and ET-3, but distinct regulatory pathways for ET-2.
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9.
authors.forename: Roma
authors.initials: R
authors.lastname: Gurusankar
authors.affiliation: Analytical Biochemistry and Proteomics Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9.
authors.forename: Prem
authors.initials: P
authors.lastname: Kumarathasan
authors.affiliation: Analytical Biochemistry and Proteomics Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9.
authors.forename: Anusha
authors.initials: A
authors.lastname: Saravanamuthu
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9.
authors.forename: Errol M
authors.initials: EM
authors.lastname: Thomson
authors.affiliation: Inhalation Toxicology Laboratory, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON, Canada K1A 0K9.
authors.forename: Renaud
authors.identifier: 0000-0002-5223-9174
authors.initials: R
authors.lastname: Vincent