Phytosterols: Physiological Functions and Potential Application.

Dietary intake of natural substances to regulate physiological functions is currently regarded as a potential way of promoting health. As one of the recommended dietary ingredients, phytosterols that are natural bioactive compounds distributed in plants have received increasing attention for their health effects. Phytosterols have attracted great attention from scientists because of many physiological functions, for example, cholesterol-lowering, anticancer, anti-inflammatory, and immunomodulatory effects. In addition, the physiological functions of phytosterols, the purification, structure analysis, synthesis, and food application of phytosterols have been widely studied. Nowadays, many bioactivities of phytosterols have been assessed in vivo and in vitro. However, the mechanisms of their pharmacological activities are not yet fully understood, and in-depth investigation of the relationship between structure and function is crucial. Therefore, a contemporaneous overview of the extraction, beneficial properties, and the mechanisms, as well as the current states of phytosterol application, in the food field of phytosterols is provided in this review.

Transcriptome Sequencing of Gingival Tissues from Impacted Third Molars Patients Reveals the Alterations of Gene Expression.

OBJECTIVE: The removal of impacted third molars by surgery may occur with a series of complications, whereas limited information about the postoperative pathogenesis is available. The objective of this study is to identify changes in gene expression after flap surgical removal of impacted third molars and provide potential information to reduce postoperative complications. METHODS: The gingival tissues of twenty patients with flap surgical removal of impacted third molars and twenty healthy volunteers were collected for gene expression testing. The collected gingival tissues were used RNA sequencing technology and quantitative real-time PCR validation was performed. DEG was mapped to protein databases such as GO and KEGG for functional annotation and, based on annotation information, for mining of differential expression genes in patients with mpacted third molars. RESULTS: A total of 555 genes were differentially expressed. Among the top up-regulated genes, HLA-DRB4, CCL20, and CXCL8 were strongly associated with immune response and signal transduction. Among the top down-regulated genes, SPRR2B, CLDN17, LCE3D and LCE3E were related to keratinocyte differentiation, IFITM5, and BGLAP were related to bone mineralization, UGT2B17 is associated with susceptibility to osteoporosis. KEGG results showed that the DEGs were related to multiple disease-related pathways. CONCLUSION: This first transcriptome analysis of gingival tissues from patients with surgical removal of impacted third molars provides new insights into postoperative genetic changes. The results may establish a basis for future research on minimizing the incidence of complications after flap-treated third molars.

Effects of epigallocatechin-3-gallate on oxidative stress, inflammation, and bone loss in a rat periodontitis model.

Background/purpose: Epigallocatechin-3-gallate (EGCG) is playing an increasingly important role in the treatment of oral diseases. However, its mechanisms remain to be clarified. This study aimed to investigate the effect of EGCG on oxidative and inflammatory stress and bone loss in experimental periodontitis. Materials and methods: Periodontitis was induced in rats, followed by gavage using different concentrations of EGCG for 5 weeks. The levels of interleukin-1ß (IL-1ß), interleukin-18 (IL-18), tumor necrosis factor-α (TNF-α), superoxide dismutase (SOD) and malondialdehyde (MDA) in rats were measured. The degree of alveolar bone loss and the number of inflammatory cells were detected. The integrated optical density of nuclear factor erythroid 2-related factor (Nrf2), heme oxygenase-1 (HO-1), NLR pyrin domain-containing 3 (NLRP3) and nuclear factor-kappaB p65 (NF-κB p65) was measured. Results: EGCG (200 mg/kg) significantly reduced alveolar bone loss in the ligated maxillary molars and the number of inflammatory cells in the EGCG-200 group compared with the periodontitis, EGCG-100 and EGCG-400 groups. 200 mg/kg was the optimal dose of EGCG and was used in subsequent experiments. The expression levels of IL-1ß, IL-18, TNF-α and MDA were significantly lower and the expression level of SOD was significantly higher in the EGCG-200 group compared with the periodontitis group. The expression of NLRP3 and NF-κB p65 was significantly decreased, while the expression of Nrf2 and HO-1 was significantly increased in the EGCG-200 group compared with the periodontitis group. Conclusion: These results suggest that EGCG inhibits oxidative stress and inflammatory responses in the periodontitis model by modulating the Nrf2/HO-1/NLRP3/NF-κB p65 signaling pathway, thereby decreasing alveolar bone loss.

Effect of Eucommia water extract on gingivitis and periodontitis in experimental rats.

Herein, we evaluated the potential therapeutic effects of water extracts from Eucommia on periodontitis in experimental rats. We ligated the maxillary second molars of Sprague-Dawley(SD) rats with 4.0 silk threads and locally smeared Porphyromonas gingivalis(P. gingivalis) to induce gingivitis and periodontitis.After the model was successfully established, we exposed the rats to Eucommia water extracts through topical smearing and intragastric administration and evaluated the therapeutic effect of the extracts on gingivitis (for a 2 week treatment period) and periodontitis (over 4 weeks). We analyzed histopathological sections of the periodontal tissue and quantified the alveolar bone resorption levels, molecules related to periodontal oxidative stress, and periodontal inflammatory factors to assess the feasibility of Eucommia in treating gingivitis and periodontitis. We found that damage to the periodontal tissue was reduced after treatment with extracts,indicating that Eucommia has a positive effect in treating gingivitis and periodontitis in experimental rats. These findings are expected to provide the foothold for future research on secondary metabolites derived from Eucommia and guide the development of novel approaches for preventing and treating periodontal disease.

CpG immunostimulatory oligodeoxynucleotide 1826 as a novel nasal ODN adjuvant enhanced the protective efficacy of the periodontitis gene vaccine in a periodontitis model in SD rats.

BACKGROUND: We previously demonstrated that nasal administration of periodontitis gene vaccine (pVAX1-HA2-fimA) or pVAX1-HA2-fimA plus IL-15 as adjuvant provoked protective immunity in the periodontal tissue of SD rats. This study evaluated the immune effect of pVAX1-HA2-fimA plus CpG-ODN 1826 as an adjuvant in the SD rat periodontitis models to improve the efficacy of the previously used vaccine. METHODS: Periodontitis was induced in maxillary second molars in SD rats receiving a ligature and infected with Porphyromonas gingivalis. Forty-two SD rats were randomly assigned to six groups: A, control without P. gingivalis; B, P. gingivalis with saline; C, P. gingivalis with pVAX1; D, P. gingivalis with pVAX1-HA2-fimA; E, P. gingivalis with pVAX1-HA2-fimA/IL-15; F, P. gingivalis with pVAX1-HA2-fimA+CpG ODN 1826 (30 µg). The levels of FimA-specific and HA2-specific secretory IgA antibodies in the saliva of rats were measured by ELISA. The levels of COX-2 and RANKL were detected by immunohistochemical assay. Morphometric analysis was used to evaluate alveolar bone loss. Major organs were observed by HE staining. RESULTS: 30 µg could be the optimal immunization dose for CpG-ODN 1826 and the levels of SIgA antibody were consistently higher in the pVAX1-HA2-fimA+CpG-ODN 1826 (30 µg) group than in the other groups during weeks 1-8 (P < 0.05, except week 1 or 2). Morphometric analysis demonstrated that pVAX1-HA2-fimA+CpG-ODN 1826 (30 µg) significantly reduced alveolar bone loss in ligated maxillary molars in group F compared with groups B-E (P < 0.05). Immunohistochemical assays revealed that the levels of COX-2 and RANKL were significantly lower in group F compared with groups B-E (P < 0.05). HE staining results of the major organs indicated that pVAX1-HA2-fimA with or without CpG-ODN 1826 was not toxic for in vivo use. CONCLUSIONS: These results indicated that CpG-ODN 1826 (30 µg) could be used as an effective and safe mucosal adjuvant for pVAX1-HA2-fimA in SD rats since it could elicit mucosal SIgA responses and modulate COX-2 and RANKL production during weeks 1-8, thereby inhibiting inflammation and decreasing bone loss.

Construction of a fusion anti-caries DNA vaccine in transgenic tomato plants for PAcA gene and cholera toxin B subunit.

Chronic bacterial infections in the oral cavity influence the development of dental caries. Mutans streptococci are the major pathogenic cause of dental caries. The World Health Organization (WHO) ranks dental caries, cancer, and cardiovascular diseases as the three major global diseases that need urgent preventative and curative measures. However, substantial evidence suggests that traditional prevention and treatment strategies are inefficient in reducing the prevalence of dental caries. For protection against caries, it is important to develop effective vaccines that induce anticolonizing immunity against Streptococcus mutans infections. In the present investigation, we constructed a fusion anti-caries DNA vaccine (PAcA-ctxB) through fusing A region of cell surface protein PAc (PAcA) coding gene of mutans streptococci with cholera toxin B subunit coding gene (CTB). Afterward, the plasmids were integrated into tomato genomes through agrobacterium-mediated plant transformation technology. The presence of transgenes in the tomato genome was confirmed by PCR, ß-glucuronidase gene (GUS), and western blot. The expression of genes was confirmed at transcription and protein level. Altogether, the results presented herein showed that transgenic tomatoes may provide a useful system for the production of human caries antigen.