Background: The purpose of this study was to investigate the anti-oral microbial activity and anti-inflammatory effects of rosmarinic acid (RA) in lipopolysaccharide (LPS)-stimulated MC3T3-E1 osteoblastic cells on a titanium (Ti) surface during osseointegration, and to confirm the possibility of using RA as a safe natural substance for the control of peri-implantitis (PI) in Ti-based dental implants. Methods: A disk diffusion test was conducted to confirm the antimicrobial activity of RA against oral microorganisms. In order to confirm the anti-inflammatory effects of RA, inflammatory conditions were induced with 100 ng/ml of LPS in MC3T3-E1 osteoblastic cells on the Ti surface treated with or without 14 mg/ml of RA. The production of nitric oxide (NO) and prostaglandin E2 (PGE2) in LPS-stimulated MC3T3-E1 osteoblastic cells on the Ti surface was confirmed using an NO assay kit and PGE2 enzyme-linked immunosorbent assay kit. Reverse transcription polymerase chain reaction and western blot analysis were performed to confirm the expression of interleukin (IL)-1β and tumor necrosis factor (TNF)-α in total RNA and protein. Results: RA showed weak antimicrobial effects against Streptococcus mutans and Escherichia coli, but no antimicrobial activity against the bacteria Aggregatibacter actinomycetemcomitans and the fungus Candida albicans. RA reduced the production of pro-inflammatory mediators, NO and PGE2, and proinflammatory cytokines, TNF-α and IL-1β, in LPS-stimulated MC3T3-E1 osteoblastic cells on the Ti surface at the protein and mRNA levels. Conclusion RA not only has anti-oral microbial activity, but also anti-inflammatory effects in LPS-stimulated MC3T3-E1 osteoblasts on the Ti surface, therefore, it can be used as a safe functional substance derived from plants for the prevention and control of PI for successful Ti-based implants.

Background: Several studies have reported associations between obesity and autonomic dysfunction. However, little research has investigated the effect of bariatric surgery on heart rate recovery (HRR) in the treadmill test and heart rate variability (HRV) in 24-hour Holter monitoring. We investigated the effects of bariatric surgery on HRR and HRV, which are parameters related to autonomic dysfunction. Methods: We retrospectively investigated patients who underwent bariatric surgery in 2019. The treadmill test, 24-hour Holter monitoring, and echocardiography were performed before and 6 months after surgery. We compared the changes in HRR in the treadmill test and HRV parameters such as the time domain and spectral domain in 24-hour Holter monitoring before and after surgery. Results: Of the 40 patients who underwent bariatric surgery, 25 patients had the treadmill test or 24-hour Holter monitoring both before and after surgery. Body weight and body mass index significantly decreased after surgery (112.86±24.37 kg vs. 89.10±20.26 kg, p<0.001; 39.22±5.69 kg/m2 vs. 31.00±5.09 kg/m2, p<0.001, respectively). HRR significantly increased (n=23; 43.00±20.97 vs. 64.29±18.49, p=0.001). The time domain of HRV parameters increased (n=21; standard deviation of the N-N interval 123.57±28.05 vs. 152.57±39.49, p=0.002 and mean N-N interval 791.57±88.84 vs. 869.05±126.31, p=0.002). Conclusions Our data showed that HRR after exercise and HRV during 24-hour Holter monitoring improved after weight reduction with bariatric surgery through improved cardiac autonomic function.

Background: The leaves of Perilla frutescens, commonly called perilla and used for food in Korea, contain components with a variety of biological effects and potential therapeutic applications. The purpose of this study was to identify the components of 70% ethanol extracted Perilla frutescens (EEPF) and determine its inhibitory effects on oral microbial activity and production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharides (LPS)-stimulated Raw264.7 macrophages, consequently, to confirm the possibility of using EEPF as a functional component for improving the oral environment and preventing inflammation. Methods: One kg of P. frutescens leaves was extracted with 70% ethanol and dried at −70o C. EEPF was analyzed using high-performance liquid chromatography analysis, and antimicrobial activity against oral microorganisms was revealed using the disk diffusion test. Cell viability was elucidated using a methylthiazolydiphenyl-tetrazolium bromide assay, and the effect of EEPF on LPS-induced morphological variation was confirmed through microscopic observation. The effect of EEPF on LPS-induced production of pro-inflammatory mediators, NO and PGE2 was confirmed by the NO assay and PGE2 enzyme-linked immunosorbent assay. Results: The main component of EEPF was rosemarinic acid, and EEPF showed weak anti-bacterial and anti-fungal effects against microorganisms living in the oral cavity. EEPF did not show toxicity to Raw264.7 macrophages and had inhibitory effects on the morphological variations and production of pro-inflammatory mediators, NO and PGE2 in LPS-stimulated Raw264.7 macrophages. Conclusion EEPF can be used as a functional material for improving the oral environment through the control of oral microorganisms and for modulating inflammation by inhibiting the production of inflammatory mediators.