MicroRNA-155 Expression is Associated with Pulpitis Progression by Targeting SHIP1

Pulpitis is a commonly seen oral inflammation condition in clinical practice, it can cause much pain for the patient and may induce infections in other systems. Much is still unknown for the pathogenic mechanism of pulpitis. In this work, we discovered that the expression of miR-155 was associated with dental pulpal inflammation both in vivo and in vitro. Experiments on odontoblast cell line MDPC-23 showed miR-155 could act as a positive regulator by increasing the production of pro-inflammatory cytokines IL-1β and IL-6 during inflammatory responses, whereas knockdown of miR-155 can reverse the effects. Bioinformatics analysis demonstrated that SHIP1 is a direct target of miR-155 in odontoblasts, this result was further verified at both mRNA and protein level. Inhibition of miR-155 resulted in the downregulation of inflammation factors, while co-transfection of si-SHIP1 and miR-155 inhibitor promoted the inflammatory responses. Treatment with miR-155 mimic or si-SHIP1 up-regulated the protein level of p-PI3K and p-AKT. By contrast, miR-155 inhibitor exerted the opposite effects. miR-155 mimics could upregulate the gene expression of IL-1β and IL-6. Co-transfection of LY294002 and miR-155 mimic attenuated the inflammatory responses. Consistent with in vitro results, miR-155−/− mice could alleviate inflammatory response, as well as decrease the activation of p-PI3K and p-AKT, whereas increase the activation of SHIP1. In conclusion, these data revealed a novel role for miR-155 in regulation of dental pulpal inflammatory response by targeting SHIP1 through PI3K/AKT signaling pathway.

MicroRNA-155 Expression Is Associated With Pulpitis Progression By Targeting SHIP1

Pulpitis is a commonly seen oral inflammation condition in clinical practice, it can cause much pain for the patient and may induce infections in other systems. Much is still unknown for the pathogenic mechanism of pulpitis. In this work, we discovered that the expression of miR-155 was associated with dental pulpal inflammation both in vivo and in vitro. Experiments on odontoblast cell line MDPC-23 showed miR-155 could act as a positive regulator by increasing the production of pro-inflammatory cytokines IL-1β and IL-6 during inflammatory responses, whereas knockdown of miR-155 can reverse the effects. Bioinformatics analysis demonstrated that SHIP1 is a direct target of miR-155 in odontoblasts, this result was further verified at both mRNA and protein level. Inhibition of miR-155 resulted in the downregulation of inflammation factors, while co-transfection of si-SHIP1 and miR-155 inhibitor promoted the inflammatory responses. Treatment with miR-155 mimic or si-SHIP1 up-regulated the protein level of p-PI3K and p-AKT. By contrast, miR-155 inhibitor exerted the opposite effects. miR-155 mimics could upregulated the gene expression of IL-1β and IL-6. Co-transfection of LY294002 and miR-155 mimic attenuated the inflammatory responses. Consistent with in vitro results, miR-155-/- mice could alleviate inflammatory response, as well as decrease the activation of p-PI3K and p-AKT, whereas increase the activation of SHIP1. In conclusion, these data revealed a novel role for miR-155 in regulation of dental pulpal inflammatory response by targeting SHIP1 through PI3K/AKT signaling pathway.

Oral hygiene and health-related quality of life in institutionalized older people

Purpose We evaluated the level of oral hygiene and its association with oral health status and need for oral treatment among older residents in long-term care facilities. In addition, the association between oral hygiene level and health-related quality of life (HRQoL) was explored. Methods This cross-sectional study assessed 231 dentate residents in long-term care facilities (71% female, mean age 81 years, 70% had dementia). Nurses assessed residents and completed questionnaires on participants’ background information, diagnoses, oral healthcare habits, and HRQoL with the 15D instrument. Two qualified dentists performed clinical oral examinations (number of teeth, plaque index, periodontal condition, open caries lesions, and dry mouth). We used a modified plaque index (PI) to measure the level of oral hygiene (good, moderate, and poor) and calculated the clinical Asymptotic Dental Score (ADS) to determine the oral inflammation burden. Results Of the residents, 21% had good, 35% moderate, and 44% poor oral hygiene according to PI. Poor oral hygiene was associated with poorer cognitive status (P = 0.010) and higher oral inflammation burden (P < 0.001). Moreover, poor oral hygiene was associated with poorer HRQoL in a correlation analysis adjusted for age and gender. Conclusions Oral hygiene of older individuals in long-term care is insufficient. Poor oral hygiene is a marker for poor HRQoL. Residents also have a high burden of oral inflammatory diseases and a need for dental care. Older residents’ oral hygiene and HRQoL may be improved with oral care education of caregivers and regular dental check-ups.

Evaluation of Anti-Inflammatory Effect of Moringa oleifera Lam. and Cyanthillium cinereum (Less) H. Rob. Lozenges in Volunteer Smokers

Smokers have high plaque accumulation that initiates gingival inflammation and progresses to periodontitis. Thus, oral hygiene to control microbial plaque formation is an effective method of preventing gingivitis. Medicinal plants such as Moringa oleifera Lam. (MO) and Cyanthillium cinereum (Less.) H. Rob. (CC) have an anti-inflammatory effect that might improve oral health in smokers. This study evaluated the effect of MO leaf and CC extracts using MO lozenges and a combination of MO + CC lozenges on oral inflammation and gingivitis in volunteer smokers. Lozenges consisting of MO and CC extracts were developed and studied in vivo. The results showed that lozenges significantly reduced oral inflammation and gingivitis in volunteers. The gingival index (GI) of group III (MO + CC lozenges) significantly decreased, while the percentage decrease of oral inflammation in group II (MO lozenges) was significantly higher than the other groups. The percentage decrease of GI values in group II (MO lozenges) and group III (MO + CC lozenges) were significantly higher than the placebo group I. Our findings indicated that MO and MO + CC lozenges reduced oral inflammation and gingivitis and showed potential to improve oral health in smokers.

ENDOTHELIAL FUNCTION IN CHILDREN WITH PERIODONTITIS

The presence of oral inflammation has recently been linked with the pathogenesis of cardiovascular diseases. Endothelial dysfunction is considered one of the pathogenetic mechanisms of a whole range of cardiovascular diseases. In the study describes links between periodontitis and endothelial dysfunction. 32 patients (16 boys and 16 girls) with periodontitis and 60 healthy children were examined. Flow-mediated vascular dilatation data were measured in all patients. Flow-mediated dilatation was 9,78±3,16% in children with periodontitis, and 12,85±3,48% in healthy children (p<0,05). Area under the dilation curve was larger in healthy children, then in children with periodontitis, 710±121%·с in comparison with 519±175%·с (p<0,05). An inverse correlation was found between flow-mediated dilatation, area under the dilation curve and periodontitis duration (r = -0,71, -0,77). A negative correlation was found between flow-mediated dilatation, area under the dilation curve and worsening of periodontitis (r = -0,70, -0,71). This study did not demonstrate association between periodontal disease in children and arterial hypertension, coronary heart disease, heart failure. However, the identified endothelial dysfunction requires protective therapeutic and preventive measures. Given the insignificant symptoms of chronic periodontitis in the examined children, it is important to activate efforts aimed at early detection and treatment of this disease. Further research is needed to clarify the prognostic role of endothelial dysfunction in chronic periodontitis.

The Advent of COVID-19; Periodontal Research Has Identified Therapeutic Targets for Severe Respiratory Disease; an Example of Parallel Biomedical Research Agendas

The pathophysiology of SARS-CoV-2 infection is characterized by rapid virus replication and aggressive inflammatory responses that can lead to acute respiratory distress syndrome (ARDS) only a few days after the onset of symptoms. It is suspected that a dysfunctional immune response is the main cause of SARS-CoV-2 infection-induced lung destruction and mortality due to massive infiltration of hyperfunctional neutrophils in these organs. Similarly, neutrophils are recruited constantly to the oral cavity to combat microorganisms in the dental biofilm and hyperfunctional neutrophil phenotypes cause destruction of periodontal tissues when periodontitis develops. Both disease models arise because of elevated host defenses against invading organisms, while concurrently causing host damage/disease when the immune cells become hyperfunctional. This represents a clear nexus between periodontal and medical research. As researchers begin to understand the link between oral and systemic diseases and their potential synergistic impact on general health, we argue that translational research from studies in periodontology must be recognized as an important source of information that might lead to different therapeutic options which can be effective for the management of both oral and non-oral diseases. In this article we connect concepts from periodontal research on oral inflammation while exploring host modulation therapy used for periodontitis as a potential strategy for the prevention of ARDS a deadly outcome of COVID-19. We suggest that host modulation therapy, although developed initially for management of periodontitis, and which inhibits proteases, cytokines, and the oxidative stress that underlie ARDS, will provide an effective and safe treatment for COVID-19.

A Cross-Sectional Study of Bitter-Taste Receptor Genotypes, Oral Health, and Markers of Oral Inflammation

(1) Background: The aetiology of oral disease is multifactorial, involving genetic and environmental factors, including dietary ones. Bitter taste genetics may be related to oral health through dietary modulation or non-gustatory roles, including modulation of inflammation. Investigations of bitter taste and oral health associations to date have been restricted to specific polymorphisms, limited outcomes (caries), and age-groups (children), and links to inflammation remain to be elucidated. (2) Methods: A cross-sectional study (n = 65) investigated the correlations between bitter taste genotypes, oral health outcomes, and oral inflammation markers. Oral examinations were conducted, including saliva testing with evaluation of flow rate, pH, and buffering and antioxidant capacity (FRAP) and IL-1β, TNF-α, IL-6 levels. DNA was collected via buccal swabs and used to evaluate the presence of multiple bitter-taste receptor gene polymorphisms. (3) Results: The major allele for TAS2R4-rs2233998, TAS2R5-rs2227264, TAS2R50-rs1376251, and TAS2R9-rs3741845 was associated with a higher mean of unstimulated salivary flow rate, FRAP, TNF-α, IL-1β, and likelihood of filled teeth. Presence of the major allele for TAS2R4-rs2234001 and TAS2R9-rs3741845 was associated with lower means FRAP, TNF-α, IL-1β, DMFT index, and likelihood of missing teeth. (4) Conclusions: These findings suggest relationships between bitter-taste genotypes, oral health outcomes, and inflammatory markers. These findings justify the need for further studies that could help identify risk groups and develop novel agents for maintaining oral health.

Efficacy and Safety of Modified Yunu-Jian in Patients with Periodontitis: A Meta-Analysis

Background. Modified Yunu-Jian (mYJ), a Chinese medicine (CM) formula, is thought to clear heat and nourish yin. Clinically, it is often used to treat oral inflammation. However, its efficacy remains controversial. Methods. The study aims to evaluate the efficacy and safety of mYJ for treating patients with periodontitis. We searched electronic databases (PubMed, Cochrane Library, Embase, China National Knowledge Infrastructure, Wanfang database, VIP database, and CBM) from inception to December 2020. Only randomized controlled trials investigating modified Yunu-Jian, with or without other medications, against controlled intervention in the treatment of patients diagnosed with periodontitis were included. Both Review Manager 5.3 and Stata 15.0 software were used to analyze the data. The Cochrane Collaborations risk of bias tool was used to assess the quality of the methods. Results. Thirteen clinical trials, involving 1179 participants, were included in our investigation. The results showed that the combination of mYJ with western medicine improved the total effective rate compared with western medicine alone (RR = 1.17, 95% CI (1.12, 1.23), P < 0.00001). The sensitivity analysis and Harbord’s test ( P = 0.255) both showed that the results were statistically robust. Moreover, the periodontal indexes (GI, SBI, PLI, and PD; P < 0.00001) of patients with periodontitis were also significantly improved after receiving the combined therapy. No serious adverse reactions were observed in the experimental groups. Conclusions. Evidence from the meta-analysis suggested that mYJ appeared to be effective and relatively safe for treating periodontitis. Because of the low quality of the methods used in the included RCTs, further studies with larger sample sizes and well-designed models are required to confirm our findings.