ABSTRACT
Homeroom teachers are not usually nutrition professionals, but they spend a lot of time with students in elementary school classrooms. This study was conducted to determine the association of homeroom teachers’ nutrition education with the dietary habits of their classroom children. The subjects were 131 homeroom teachers and their 1,102 children from 17 elementary schools in Gyeonggi, Korea. Self-administered questionnaires to collect information on dietary habits were conducted in December 2016. The dietary habits were determined with the adherences to the Dietary Guidelines for Adults and Children, respectively, by coding the better diet life with a higher score. The significances between groups according to teachers’ implementation of nutrition education (106 implemented, 25 not implemented) were analyzed by using SPSS at P＜0.05. Implementing nutrition education was not associated with the dietary habits of teachers themselves, but their students. Therefore, the students of teachers who implemented nutrition education had significantly higher adherence to 8 items out of 19 items (P＜0.05, P＜0.01). More of the students considered themselves as non-picky eaters (P＜0.05), tried to eat all the foods served at school lunch even when it contained unwanted ingredients (P＜0.01), and agreed on the need of nutrition education (P＜0.01), as compared to their counterparts. Conclusively, this study suggests that nutrition education delivered by homeroom teachers may be associated with more desirable dietary habits of students, even though homeroom teachers are not nutrition professionals. Therefore, efforts should be undertaken to develop and provide proper contents for homeroom teachers to use in nutrition education for elementary students.
ABSTRACT
Xylitol is well-known to have an anti-caries effect by inhibiting the replication of cariogenic bacteria. In addition, xylitol enhances saliva secretion. However, the precise molecular mechanism of xylitol on saliva secretion is yet to be elucidated. Thus, in this study, we aimed to investigate the stimulatory effect of xylitol on saliva secretion and to further evaluate the involvement of xylitol in muscarinic type 3 receptor (M3R) signaling. For determining these effects, we measured the saliva flow rate following xylitol treatment in healthy individuals and patients with dry mouth. We further tested the effects of xylitol on M3R signaling in human salivary gland (HSG) cells using real-time quantitative reverse-transcriptase polymerase chain reaction, immunoblotting, and immunostaining. Xylitol candy significantly increased the salivary flow rate and intracellular calcium release in HSG cells via the M3R signaling pathway. In addition, the expressions of M3R and aquaporin 5 were induced by xylitol treatment. Lastly, we investigated the distribution of M3R and aquaporin 5 in HSG cells. Xylitol was found to activate M3R, thereby inducing increases in Ca²⁺ concentration. Stimulation of the muscarinic receptor induced by xylitol activated the internalization of M3R and subsequent trafficking of aquaporin 5. Taken together, these findings suggest a molecular mechanism for secretory effects of xylitol on salivary epithelial cells.
Subject(s)
Humans , Aquaporin 5 , Bacteria , Calcium , Calcium Signaling , Candy , Epithelial Cells , Immunoblotting , Mouth , Polymerase Chain Reaction , Receptors, Muscarinic , Saliva , Salivary Glands , XylitolABSTRACT
Streptococcus mutans (S. mutans), a major aetiologic agent of dental caries, is involved in systemic diseases, such as bacterial endocarditis, if it enters the bloodstream through temporary bacteraemia. Interleukin (IL)-1β, a proinflammatory cytokine, is related to the host defences against pathogens, and its synthesis, maturation, and secretion are tightly regulated by the activation of the inflammasome, an inflammatory signalling complex. This study examined the signalling mechanism of IL-1β secretion and the inflammasome pathway induced by S. mutans to explain the molecular mechanism through which systemic infection by oral streptococci can occur. After infection of THP-1 cells with S. mutans, the expression of inflammasome components was detected using various methods. S. mutans induced IL-1β secretion via caspase-1 activation, and S. mutans-induced IL-1β secretion required absent in melanoma (AIM2), NLR family pyrin domain-containing 3 (NLRP3) and NLR family CARD domain-containing 4 (NLRC4) inflammasome activation. In particular, the S. mutans-induced NLRP3 inflammasome was mediated by adenosine triphosphate (ATP) release, potassium depletion and lysosomal damage. Our study provides novel insight into the innate immune response against S. mutans infection.