Norishige Kawanishi1, Noriyuki Hoshi2, Sugimoto Masahiro3, Ayame Enomoto4, Sana Ota4, Miku Kaneko4, Tomoyoshi Soga4, Masaru Tomita4, Katsuhiko Kimoto1. 1. Division of Prosthodontics and Oral Rehabilitation, Department of Oral Function and Restoration, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka, Yokosuka 238-8580, Japan. 2. Division of Prosthodontics and Oral Rehabilitation, Department of Oral Function and Restoration, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka, Yokosuka 238-8580, Japan. Electronic address: hoshi@kdu.ac.jp. 3. Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka, Yokosuka, Kanagawa 238-8580, Japan; Health Promotion and Preemptive Medicine, Research and Development Center for Minimally Invasive Therapies Tokyo Medical University, 6-1-1 Shinjyuku, Shinjyuku 160-0022, Japan; Institute for Advanced Biosciences, Keio University, 246-2 Turuoka, 997-0052, Japan; Research and Development Center for Precision Medicine, University of Tsukuba, Tukuba, Ibaraki 305-8550, Japan. 4. Institute for Advanced Biosciences, Keio University, 246-2 Turuoka, 997-0052, Japan.
Abstract
BACKGROUND: Salivary secretion is an important parameter reflecting the health status of an individual and has been used clinically for the diagnosis of various oral diseases, such as xerostomia. Salivary metabolomic profiling is considered an emerging potential tool for the detection of various systemic diseases. To our knowledge, this is the first study to investigate the quantitative relationship between salivary secretion volume and salivary metabolomic profile. METHODS: To evaluate inter- and intra-day variations in salivary secretion, 234 saliva samples were collected three times per day for three days from 13 subjects and analyzed. Capillary electrophoresis-mass spectrometry was used for non-targeted quantification of water-soluble metabolites. RESULTS: No significant inter- or intra-day variations were observed in salivary secretion volume. No significant inter-day variations were observed in metabolomic patterns. In contrast, significant intra-day variations were observed in salivary metabolomic profiles. The difference was more obvious for stimulated saliva than for unstimulated saliva. These profile changes were independent of salivary secretion volume. CONCLUSIONS: Our results indicated that diurnal change had a greater effect on salivary metabolomic profiles than the other factors. Hence, sampling time should be tightly controlled to minimize unexpected bias in the clinical use of salivary metabolomics.
BACKGROUND: Salivary secretion is an important parameter reflecting the health status of an individual and has been used clinically for the diagnosis of various oral diseases, such as xerostomia. Salivary metabolomic profiling is considered an emerging potential tool for the detection of various systemic diseases. To our knowledge, this is the first study to investigate the quantitative relationship between salivary secretion volume and salivary metabolomic profile. METHODS: To evaluate inter- and intra-day variations in salivary secretion, 234 saliva samples were collected three times per day for three days from 13 subjects and analyzed. Capillary electrophoresis-mass spectrometry was used for non-targeted quantification of water-soluble metabolites. RESULTS: No significant inter- or intra-day variations were observed in salivary secretion volume. No significant inter-day variations were observed in metabolomic patterns. In contrast, significant intra-day variations were observed in salivary metabolomic profiles. The difference was more obvious for stimulated saliva than for unstimulated saliva. These profile changes were independent of salivary secretion volume. CONCLUSIONS: Our results indicated that diurnal change had a greater effect on salivary metabolomic profiles than the other factors. Hence, sampling time should be tightly controlled to minimize unexpected bias in the clinical use of salivary metabolomics.
Authors: Soile Turunen; Jenni Puurunen; Seppo Auriola; Arja M Kullaa; Olli Kärkkäinen; Hannes Lohi; Kati Hanhineva Journal: Metabolomics Date: 2020-08-25 Impact factor: 4.290