Jitjiroj Ittichaicharoen1,2,3, Arintaya Phrommintikul3,4, Nipon Chattipakorn2,3,5, Siriporn Chattipakorn6,7,8. 1. Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, 50200, Thailand. 2. Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand. 3. Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, 50200, Thailand. 4. Cardiology Unit, Department of Internal Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand. 5. Cardiac Electrophysiology Unit, Department of Physiology, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand. 6. Department of Oral Biology and Diagnostic Sciences, Faculty of Dentistry, Chiang Mai University, Chiang Mai, 50200, Thailand. scchattipakorn@gmail.com. 7. Neurophysiology Unit, Cardiac Electrophysiology Research and Training Center, Faculty of Medicine, Chiang Mai University, Chiang Mai, 50200, Thailand. scchattipakorn@gmail.com. 8. Center of Excellence in Cardiac Electrophysiology Research, Chiang Mai University, Chiang Mai, 50200, Thailand. scchattipakorn@gmail.com.
Abstract
OBJECTIVES: The present study is to investigate the salivary gland function of metabolic syndrome (MetS) patients, as indicated by salivary flow rate, amylase activity, and salivary oxidative stress, by measuring MDA level. MATERIALS AND METHODS: One hundred and eighty-one MetS patients from Maharaj Nakorn Chiang Mai Hospital were enrolled onto this study. The metabolic parameters of each patient were collected and evaluated. Unstimulated saliva was also collected for 5 min. Salivary gland functions, including salivary flow rate, amylase activity, and salivary MDA levels, were investigated. RESULTS: High levels of triglycerides, high-density lipoprotein, blood pressure, and waist circumference in MetS patients did not show a correlation with altered salivary gland function. However, a decrease in salivary flow rate was observed in MetS patients with hyperglycemia. In addition, decreased amylase activity was found in MetS patients with obesity (BMI ≥ 23 kg/m2). Salivary amylase activity of MetS patients treated with dipeptidyl peptidase IV (DPP-IV) inhibitor was significantly greater than that observed in MetS patients without a DPP-IV inhibitor. Moreover, the salivary amylase activity in MetS patients was found to be independently positively correlated with DPP-IV inhibitor therapy (r = 0.708, p < 0.01). CONCLUSION: These findings suggest that obesity and hyperglycemia in MetS patients were associated with the impairment of salivary glands. Treatment with a DPP-IV inhibitor was found to exert beneficial effects on the salivary gland. CLINICAL RELEVANCE: This study demonstrated the impairment of salivary glands of MetS patients and the beneficial effect of DPP-IV inhibitor treatment in the salivary glands.
OBJECTIVES: The present study is to investigate the salivary gland function of metabolic syndrome (MetS) patients, as indicated by salivary flow rate, amylase activity, and salivary oxidative stress, by measuring MDA level. MATERIALS AND METHODS: One hundred and eighty-one MetS patients from Maharaj Nakorn Chiang Mai Hospital were enrolled onto this study. The metabolic parameters of each patient were collected and evaluated. Unstimulated saliva was also collected for 5 min. Salivary gland functions, including salivary flow rate, amylase activity, and salivary MDA levels, were investigated. RESULTS: High levels of triglycerides, high-density lipoprotein, blood pressure, and waist circumference in MetS patients did not show a correlation with altered salivary gland function. However, a decrease in salivary flow rate was observed in MetS patients with hyperglycemia. In addition, decreased amylase activity was found in MetS patients with obesity (BMI ≥ 23 kg/m2). Salivary amylase activity of MetS patients treated with dipeptidyl peptidase IV (DPP-IV) inhibitor was significantly greater than that observed in MetS patients without a DPP-IV inhibitor. Moreover, the salivary amylase activity in MetS patients was found to be independently positively correlated with DPP-IV inhibitor therapy (r = 0.708, p < 0.01). CONCLUSION: These findings suggest that obesity and hyperglycemia in MetS patients were associated with the impairment of salivary glands. Treatment with a DPP-IV inhibitor was found to exert beneficial effects on the salivary gland. CLINICAL RELEVANCE: This study demonstrated the impairment of salivary glands of MetS patients and the beneficial effect of DPP-IV inhibitor treatment in the salivary glands.