Abstract details
| Abstract-ID: | 1018 |
| Title of the paper: | Acute effects of different exercise intensities and durations on salivary LL-37 secretion |
| Authors: | Ito, R., Uchino, T.1, Uchida, M.1, Fujie, S.1, Iemitsu, K.1, Kojima, C.1, Nakamura, M.2, Shimizu, K.2, Tanimura, Y.2, Shinohara, Y.1, Hashimoto, T.1, Isaka, T.1, Iemitsu, M.1 |
| Institution: | 1. Ritsumeikan university, 2. Japan Institute of Sports Sciences |
| Department: | 1. Faculty of Sports and Health Sciences |
| Country: | Japan |
| Abstract text | INTRODUCTION: Antimicrobial peptides LL-37, present in the saliva, has an important role in oral immune function. LL-37 exerts antimicrobial activity by disrupting the membranes of bacterial and viral cells. A few studies indicated an increase in salivary LL-37 secretion after high-intensity and long-duration acute exercise [1, 2]. However, it remains unclear whether the acute effects of different exercise intensities or durations on salivary LL-37 secretion. This study aimed to clarify the acute effects of different exercise intensities and durations on the secretion of LL-37 in saliva. METHODS: Fourteen healthy young men (age: 21.6 ± 1.6 years, height: 173.8 ± 3.8 cm, weight: 63.8 ± 6.0 kg, VO2max: 42.0 ± 4.7 ml/kg/min) with no exercise habits participated in this study. Maximal oxygen uptake (VO2max) was measured approximately 1 week before the main trials. All participants randomly performed [Intensity study] cycling exercise for 30 minutes at 35% (Low), 55% (Moderate), and 75%VO2max (High) and [Duration study] cycling exercise for 30 (Short), 60 (Middle), and 90-minutes (Long) at 55%VO2max. Saliva samples were collected before (baseline), immediately after (post), and 60 minutes after exercise (post-60 min) each trial. The salivary LL-37 concentrations were measured by enzyme-linked immunoassay. The effects of different exercise intensities (Low, Moderate, High) or durations (Short, Middle, Long) were determined using three trials × three time points (baseline, post, and post-60 min each exercise) of two-way repeated-measures ANOVA. A p<0.05 was considered statistically significant. RESULTS: In the intensity study, no significant differences in the percentage change from baseline were observed in salivary LL-37 concentration at post as well as post-60 min among the Low, Moderate, and High trials. In the duration study, the percentage change from baseline in salivary LL-37 concentration at post significantly increased by 40.7% in the Middle trial and 58.6% in the Long trial compared to the Short trial (each p<0.05). However, no significant differences were observed in the percentage change in salivary LL-37 concentration at post-60 min compared to baseline among the three different exercise durations trials. CONCLUSION: These results suggest that salivary LL-37 secretion may be independent of exercise intensity and may be stimulated depending on exercise duration. |
| Topic: | Molecular Biology and Biochemistry |
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