Takeo Kikuchi1, Wakako Sakaguchi1, Juri Saruta2, Yuko Yamamoto3, Masahiro To4, Yuki Kurimoto5, Tomoko Shimizu6, Keiichi Tsukinoki1. 1. Division of Environmental Pathology, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan. 2. Division of Environmental Pathology, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan. Electronic address: saruta@kdu.ac.jp. 3. Department of Dental Hygiene, Kanagawa Dental University Junior College, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan. 4. Division of Dental Anatomy, Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan. 5. Department of Total Education, School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa, 238-8580, Japan. 6. Department of Highly Advanced Oral Medicine, Graduate School of Dentistry, Kanagawa Dental University, 3-31-6 Tsuruya, Kanagawa-ku, Yokohama, Kanagawa, 221-0835, Japan.
Abstract
OBJECTIVES: Salivary glands produce brain-derived neurotrophic factor (BDNF), which increases plasma BDNF content. Salivary BDNF influences the hippocampus and enhances anxiety-like behaviors. Dyslipidemia affects the brain, promoting depression and anxiety-like behaviors. This study was performed to investigate whether hypertriglyceridemia influences salivary BDNF expression. METHODS: Hypertriglyceridemia was induced in rats by high-fat diet intake for 10 weeks. BDNF protein levels in the saliva and submandibular glands were measured using enzyme-linked immunosorbent assay (ELISA). Bdnf mRNA levels in the submandibular gland were determined using real-time polymerase chain reaction. RESULTS: A hypertriglyceridemia rat model was established. Body weight did not differ between the control and hypertriglyceridemia groups. Bdnf mRNA and protein expression was increased in the submandibular gland in the hypertriglyceridemia group compared to the control group. BDNF expression was also significantly increased in the saliva of the hypertriglyceridemia group. CONCLUSIONS: This is first study to show that hypertriglyceridemia induces BDNF expression in the rat submandibular gland and suggests that salivary BDNF is associated with lipid metabolism.
OBJECTIVES: Salivary glands produce brain-derived neurotrophic factor (BDNF), which increases plasma BDNF content. Salivary BDNF influences the hippocampus and enhances anxiety-like behaviors. Dyslipidemia affects the brain, promoting depression and anxiety-like behaviors. This study was performed to investigate whether hypertriglyceridemia influences salivary BDNF expression. METHODS:Hypertriglyceridemia was induced in rats by high-fat diet intake for 10 weeks. BDNF protein levels in the saliva and submandibular glands were measured using enzyme-linked immunosorbent assay (ELISA). Bdnf mRNA levels in the submandibular gland were determined using real-time polymerase chain reaction. RESULTS: A hypertriglyceridemiarat model was established. Body weight did not differ between the control and hypertriglyceridemia groups. Bdnf mRNA and protein expression was increased in the submandibular gland in the hypertriglyceridemia group compared to the control group. BDNF expression was also significantly increased in the saliva of the hypertriglyceridemia group. CONCLUSIONS: This is first study to show that hypertriglyceridemia induces BDNF expression in the rat submandibular gland and suggests that salivary BDNF is associated with lipid metabolism.