Effects and Safety of Xylitol on Middle Ear Epithelial Cells

Abstract

OBJECTIVE:Xylitol is a natural sugar known to reduce dental decay. Recently, several epidemiology studies have also shown that xylitol can prevent acute otitis media in children. It is assumed that these effects are related to the inhibition of bacterial growth in the nasopharynx. However, the effects and safety of xylitol in middle ear epithelial cells, which play a key role in otitis media, have not been investigated. The present study was performed to investigate whether xylitol shows antiinflammatory or antioxidative effects on human middle ear epithelial cells and to assess its safety profile for clinical use. MATERIALS and METHODS:We induced inflammation in human middle ear epithelial cells (HMEEC) with lipopolysaccharide (LPS). After xylitol treatment, we measured expression levels of the inflammatory cytokines TNF-α and COX-2 and the mucin gene MUC5AC using semiquantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis. Cell viability and morphological changes following xylitol treatment were investigated by 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyltetrazolium bromide (MMT) assay, flow cytometry, and Hoechst 33342 staining in human middle ear epithelial cells and mouse inner ear cells. RESULTS:Inflammatory cytokines and mucin gene expression were unaffected by xylitol. In addition, xylitol showed neither antioxidative effects nor cytotoxicity and did not stimulate apoptosis or necrosis of human middle ear epithelial cells or inner ear cells, even at high doses. CONCLUSION:Xylitol did not show antiinflammatory or antioxidative effects on HMMEC. It showed no toxicity in middle ear and inner ear cells. Xylitol may therefore be used safely to prevent acute otitis media.

Sugar alcohols—their role in the modern world of sweeteners: a review

“…It was discovered in 1891 and since the 1960s has been used as a sweetener. It can be found in nature in many fruits and vegetables, berries, oats and mushrooms and is produced in small quantities in human organism [21,22,[95][96][97][98][99].…”

“…It can be metabolized directly in the liver or indirectly by fermentative degradation by intestinal flora (Table 3) [108]. Human tolerance of xylitol amounts to 100 g per day [96].…”

“…Its regular consumption in adequate doses results in the reduction of tooth decay [26,97,109]. Besides reducing the development of dental caries, it also plays a role in a decrease in plaque formation as it inhibits the growth and metabolism of Streptococcus mutans and Streptococcus sobrinus, which are responsible for caries and dental plaque acid production, respectively [96,[110][111][112][113]. There are results of several clinical studies which confirm that the daily usage of small amounts of xylitol significantly decreases the risk of dental caries [3,95,114].…”

“…Moreover, xylitol acts as a statherin, which is a polypeptide that provides a protective and stabilized environment for teeth [3]. There is also data implying that xylitol reduces the incidence of ear infections and has an anti-bacterial effect on pneumococcal nasal colonization [96,[118][119][120]. This sugar alcohol is used as an energy source in infusion therapy [121].…”

Physicochemical Properties of Dried Apple Slices: Impact of Osmo-Dehydration, Sonication, and Drying Methods

“…Even fewer publications relate to experiments with xylitol intake. The most common is the safe value of daily xylitol intake by adults, up to 100 g [30,31]. Four out of 13 children had diarrhea after consuming over 65 g of xylitol per day [32].…”