Salivary flow rate and biochemical composition analysis in stimulated whole saliva of children with cystic fibrosis

Current developments and opportunities of pluripotent stem cells-based therapies for salivary gland hypofunction

Salivary gland hypofunction (SGH) caused by systemic disease, drugs, aging, and radiotherapy for head and neck cancer can cause dry mouth, which increases the risk of disorders such as periodontitis, taste disorders, pain and burning sensations in the mouth, dental caries, and dramatically reduces the quality of life of patients. To date, the treatment of SGH is still aimed at relieving patients' clinical symptoms and improving their quality of life, and is not able to repair and regenerate the damaged salivary glands. Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), and extended pluripotent stem cells (EPSCs), are an emerging source of cellular therapies that are capable of unlimited proliferation and differentiation into cells of all three germ layers. In recent years, the immunomodulatory and tissue regenerative effects of PSCs, their derived cells, and paracrine products of these cells have received increasing attention and have demonstrated promising therapeutic effects in some preclinical studies targeting SGH. This review outlined the etiologies and available treatments for SGH. The existing efficacy and potential role of PSCs, their derived cells and paracrine products of these cells for SGH are summarized, with a focus on PSC-derived salivary gland stem/progenitor cells (SGS/PCs) and PSC-derived mesenchymal stem cells (MSCs). In this Review, we provide a conceptual outline of our current understanding of PSCs-based therapy and its importance in SGH treatment, which may inform and serve the design of future studies.

Differentiation and Characterization of Cystic Fibrosis Transmembrane Conductance Regulator Knockout Human Pluripotent Stem Cells into Salivary Gland Epithelial Progenitors

The differentiation of pluripotent stem cells has been used to study disease mechanisms and development. We previously described a method for differentiating human pluripotent stem cells (hPSCs) into salivary gland epithelial progenitors (SGEPs). Here, cystic fibrosis transmembrane conductance regulator (CFTR) knockout hPSCs were differentiated into SGEPs derived from CFTR knockout hESCs (CF-SGEPs) using the same protocol to investigate whether the hPSC-derived SGEPs can model the characteristics of CF. CF-a disease that affects salivary gland (SG) function-is caused by mutations of the CFTR gene. Firstly, we successfully generated CFTR knockout hPSCs with reduced CFTR protein expression using the CRISPR-Cas9 system. After 16 days of differentiation, the protein expression of CFTR decreased in SGEPs derived from CFTR knockout hESCs (CF-SGEPs). RNA-Seq revealed that multiple genes modulating SG development and function were down-regulated, and positive regulators of inflammation were up-regulated in CF-SGEPs, correlating with the salivary phenotype of CF patients. These results demonstrated that CFTR suppression disrupted the differentiation of hPSC-derived SGEPs, which modeled the SG development of CF patients. In summary, this study not only proved that the hPSC-derived SGEPs could serve as manipulable and readily accessible cell models for the study of SG developmental diseases but also opened up new avenues for the study of the CF mechanism.

Buccal films: A review of therapeutic opportunities, formulations & relevant evaluation approaches

The potential of the mucoadhesive film technology is hard to ignore, owing to perceived superior patient acceptability versus buccal tablets, and significant therapeutic opportunities compared to conventional oral drug delivery systems, especially for those who suffer from dysphagia. In spite of this, current translation from published literature into the commercial marketplace is virtually non-existent, with no authorised mucoadhesive buccal films available in the UK and very few available in the USA. This review seeks to provide an overview of the mucoadhesive buccal film technology and identify key areas upon which to focus scientific efforts to facilitate the wider adoption of this patient-centric dosage form. Several indications and opportunities for development were identified, while discussing the patient-related factors influencing the use of these dosage forms. In addition, an overview of the technologies behind the manufacturing of these films was provided, highlighting manufacturing methods like solvent casting, hot melt extrusion, inkjet printing and three-dimensional printing. Over thirty mucoadhesive polymers were identified as being used in film formulations, with details surrounding their mucoadhesive capabilities as well as their inclusion alongside other key formulation constituents provided. Lastly, the importance of physiologically relevant in vitro evaluation methodologies was emphasised, which seek to improve in vivo correlations, potentially leading to better translation of mucoadhesive buccal films from the literature into the commercial marketplace.

Dental caries and associated salivary biomarkers in patients with cystic fibrosis

PURPOSE

To evaluate the caries status of the Cystic fibrosis (CF) children and adolescents with the comparation of some biochemical markers, secretory-immunoglobulin-A (sIgA), and antimicrobial peptides in the saliva.

METHODS

In this cross-sectional descriptive study, the approval Ethics Board was obtained. Unstimulated saliva samples were collected from CF and healthy control children (non-CF) patients. Both groups underwent the same dental and periodontal evaluation scheme of the assessment. Human beta defensin (HBD1), human alpha defensin (HNP-1), cathelicidin (LL-37), sIgA in saliva were evaluated by enzyme-linked immunoassay method. A general biochemical analysis was performed. Statistical analysis was performed by using Statistical Package for the Social Sciences Version 20.0 (SPSS Inc.).

RESULTS

A total of 21 (9 male, 12 female) CF and 23 (11 male, 12 female) control patients were participated with the mean age of 10.17 ± 3.38 and 9.52 ± 2.15 years, respectively. In control children, DMFT/S (decayed-missing-filled-tooth/surface-in-permanent-dentition), dmft/s (decayed-missing-filled-tooth/surface-in-primary-dentition) values were higher; DT (decayed-tooth in permanent dentition), ft (filled-tooth in primary dentition) and plaque index values were statistically significantly higher (p = 0.042, p = 0.005, p = 0.038, respectively) than CF patients. Bicarbonate was higher in control group; sodium, chloride, and total protein were higher in CF group; magnesium, calcium and phosphate levels were similar in each group (p > 0.05). Alpha and beta defensin-1 levels in control group was statistically significantly higher (p = 0.037 and p = 0.020, respectively), while LL37 and sIgA were not statistically significantly higher (p > 0.05) than CF group.

CONCLUSIONS

Children with CF had lower caries in permanent teeth, filling in primary teeth, and an altered salivary biomarker profile, especially in HNB1, HNP1. Therefore, it is important to conduct periodic oral-dental controls among CF patients during their childhood.

Review of paediatric gastrointestinal physiology relevant to the absorption of orally administered medicines

Despite much progress in regulations to improve paediatric drug development, there remains a significant need to develop better medications for children. For the design of oral dosage forms, a detailed understanding of the specific gastrointestinal (GI) conditions in children of different age categories and how they differ from GI conditions in adults is essential. Several review articles have been published addressing the ontogeny of GI characteristics, including luminal conditions in the GI tract of children. However, the data reported in most of these reviews are of limited quality because (1) information was cited from very old publications and sometimes low quality sources, (2) data gaps in the original data were filled with textbook knowledge, (3) data obtained on healthy and sick children were mixed, (4) average data obtained on groups of patients were mixed with data obtained on individual patients, and (5) results obtained using investigative techniques that may have altered the outcome of the respective studies were considered. Consequently, many of these reviews draw conclusions that may be incorrect. The aim of the present review was to provide a comprehensive and updated overview of the available original data on the ontogeny of GI luminal conditions relevant to oral drug absorption in the paediatric population. To this end, the PubMed and Web of Science metadatabases were searched for appropriate studies that examined age-related conditions in the oral cavity, esophagus, stomach, small intestine, and colon. Maturation was observed for several GI parameters, and corresponding data sets were identified for each paediatric age group. However, it also became clear that the ontogeny of several GI traits in the paediatric population is not yet known. The review article provides a robust and valuable data set for the development of paediatric in vitro and in silico biopharmaceutical tools to support the development of age-appropriate dosage forms. In addition, it provides important information on existing data gaps and should provide impetus for further systematic and well-designed in vivo studies on GI physiology in children of specific age groups in order to close existing knowledge gaps and to sustainably improve oral drug therapy in children.

Role of Salivary Biomarkers in Cystic Fibrosis: A Systematic Review

Background

Saliva biomarkers could be easily used as a noninvasive alternative tool for diagnosing cystic fibrosis (CF) disease. In this study, the significance of changes in salivary compositions in patients with CF was systematically reviewed.

Methods

An electronic search was utilized to include studies published in English, with case-control, cohort, or cross-sectional design. The evaluated salivary components were extracted and summarized. The included studies were assessed using the Strengthening the Reporting of Observational Studies in Epidemiology checklist.

Results

Out of 498 identified studies, nine met the eligibility criteria. Salivary electrolytes showed a substantial alteration in the CF group, especially with chloride and sodium. Total protein concentration was higher in patients with CF. However, SCN– concentration was lower in patients with CF. In addition, a reduction in the salivary flow rate and amylase levels was found in patients with CF.

Conclusion

Alterations in salivary biomarkers among patients with CF could be used as a promising diagnostic tool for cystic fibrosis.

Effect of Low Amperage Electric Current on Staphylococcus Aureus-Strategy for Combating Bacterial Biofilms Formation on Dental Implants in Cystic Fibrosis Patients, In Vitro Study

Cystic fibrosis is an inherited disease that affects multiple organs and systems. The oral cavity can serve as a substantial source of bacteria, causing respiratory infections and diseases which continue to dictate the clinical course of the disease and prognosis in patients with CF. Low voltage and electric current could effectively kill bacteria and biofilms, and the activity of milliampere currents could be used as an effective method of fighting bacteria. This study evaluated the effect of low amperage electric current on the formation of Staphylococcus aureus biofilms on dental implants such as titanium and zirconium in patients with cystic fibrosis. Our studies suggest that a constant electric current at a low intensity of 1 mA and 10 mA is inhibiting bacterial adhesion, detaching biofilm-forming bacteria on biomaterials used in dental implants such as titanium and zirconium, and destroying bacterial cells of Staphylococcus aureus strains. In addition, we observed the selection of an appropriate biomaterial for implants in people affected by chronic diseases, such as CF, should be carefully planned.

Estimation of Proinflammatory Factors in the Saliva of Adult Patients with Cystic Fibrosis and Dental Caries

Introduction: The available literature lacks data regarding the levels of resistin, lysozyme, lactoferrin, α-amylase activity, pH, and saliva buffer capacity, as well as oral health and hygiene in the group of adult patients with cystic fibrosis (CF). The aim of the research was to assess the selected saliva parameters in patients diagnosed with cystic fibrosis. Materials and methods: Examined group was composed of 40 patients diagnosed with CF, while the control group of 40 healthy individuals. Both groups underwent the same scheme of the assessment (DMT index, salivary pH, buffer capacity, analysis of total sialic acid, total protein estimation, lysozyme levels estimation, lactofferin levels measurement, α-amylase activity, estimation of the levels of resistin and TNF-α). Results: In the examined group, there were higher values of decayed teeth as well as values of sialic acid, total protein, lactoferrin, α-amylase, and TNF-α. However, mean lysozyme, and resistin levels, as well as pH and buffer capacity of the saliva, were lower. Conclusions: New diagnostic methods, including the evaluation of selected salivary biochemical parameters, may indicate the existence of factors predisposing to severe tooth decay in the study group. Appropriate preventive treatment to combat dental caries in adult patients with CF will significantly improve their comfort and life expectancy.

Ratio of Salivary Sialic Acid to Fucose as Tumor Markers in Potentially Malignant Disorders and Oral Cancer

BACKGROUND

Lack of noninvasive and economically feasible laboratory investigations in the early detection of cancer is a set-back in the prognosis of oral cancer (OC) patients.

AIMS

The aim of the study was to evaluate the ratio of sialic acid to fucose in salivary samples of OC and oral potentially malignant disorder (OPMD) patients.

MATERIALS AND METHODS

A total of 60 participants were selected and divided into three groups based on clinical and histopathological diagnosis: OC patients (n = 20), OPMD patients (n = 20), and healthy patients (n = 20). Unstimulated whole saliva of 1.5 ml was collected from the selected individuals for evaluating the salivary levels of sialic acid and fucose using the biochemical assay.

RESULTS

The difference in mean salivary sialic acid and fucose among the study groups was statistically significant (P = 0.001); one-way analysis of variance. The mean sialic acid to fucose ratio in the control group, OPMD group, and OC group were 0.34 mg/dl, 0.88 mg/dl, and 0.89 mg/dl, respectively. OC patients had significant elevation in the levels of salivary sialic acid, fucose, and their ratios (P = 0.001, P = 0.001, P = 0.003, respectively); Tukey's post hoc test.

CONCLUSIONS

The ratio of salivary sialic acid to fucose is a predictable tumor marker for the diagnosis of OC. Further investigations are required to evaluate the influence of OC grading on this diagnostic marker.

Salivary Biomarkers and Oral Microbial Load in Relation to the Dental Status of Adults with Cystic Fibrosis

The mutation of cystic fibrosis transmembrane conductance regulator (CFTR) can modify the physical and chemical properties of saliva, which in turn can affect the oral microflora and oral health in patients with cystic fibrosis (CF). The aim of the study was to examine oral health status, salivary properties, and total oral bacteria count in CF adults. Dental status was assessed using the decayed missing filled surfaces (DMF-S) index, and oral clearness using the approximal plaque index (API). The Saliva-Check BUFFER test was used to assess saliva, and real-time polymerase chain reaction (PCR) test to determine the total oral bacteria count. CF patients in comparison to healthy controls showed a higher level of examined clinical indices, higher total oral bacteria count, lower salivary flow rate, lower salivary pH, and increased viscosity. Conclusions: In CF patients, saliva properties, accompanied by insufficient dental care, might be an essential dental caries risk factor. In CF patients, among the etiological factors for dental caries, the bacterial agent seems to be less significant. The frequent and long-term infectious pharmacotherapy can probably explain that. A great deal of the information collected on the oral environment in CF patients, which has helped us understand the etiological conditions for inflammation and infection in this area of the body, indicates that proper dental care can mostly counteract these pathologies.

Toothbrushes may convey bacteria to the cystic fibrosis lower airways

Recent findings indicate that the oral cavity acts as a bacterial reservoir and might contribute to the transmission of bacteria to the lower airways. Control of a potentially pathogenic microbiota might contribute to prevent the establishment of chronic infection in cystic fibrosis. We evaluated the presence of CF microorganisms in saliva and toothbrushes of CF patients and verify their possible transmission to lower airways. Methods: We assessed the presence of P. aeruginosa, S. aureus, S. maltophilia, A. xylosoxidans, S. marcescens, and yeasts in saliva, toothbrushes and sputum of 38 CF patients and assessed the clonal identity of the strains occurring contemporary in multiple sites by PFGE. Results: At least one of the investigated species was isolated from 60 saliva samples and 23 toothbrushes. S. aureus was the most abundant species, followed by Candida spp. 31 patients contemporary had the same species in sputum and saliva/toothbrush: in most cases, clonal identity of the strains among the different sites was confirmed. Conclusion: Toothbrushes may be sources of oral contamination and might act as reservoirs favoring transmission of potentially pathogenic microorganisms from the environment to the oral cavity and eventually to the LAW. Oral hygiene and toothbrush care are important strategies to prevent CF lung infections.

Oral health of cystic fibrosis patients at a north american center: A pilot study

Background

The objective of this study was to describe the oral health status of Cystic Fibrosis (CF) children in a US facility.

Material and Methods

Twenty CF children ages 6-18 were recruited from Children’s Hospital of Wisconsin Pulmonary Clinic. Parents completed a health questionnaire. Clinical examinations checked dental caries using the dmft/DMFT index, dental hygiene using the Simplified Greene-Vermillion Index (DI-S), gingival inflammation using the Community Periodontal Index of Treatment Needs, and enamel defects using the modified Developmental Defects of Enamel Index.

Results

The majority (90%) brush twice a day, 65% consume sugary snacks, and 70% visit the dentist every 6 months. Clinically, they presented DMFT 0.25 and dmft 0.90, fair oral hygiene with DI-S 1.02, 75% had mild gingivitis and 50% had enamel defects. The more antibiotics they took, significantly more frequent (p=0.007) and more severe (p=0.017) enamel defects were noted. Similar trend was found between the number of surgeries and the presence of enamel defects (p=0.076) and dental caries (p=0.028).

Conclusions

Within the limitations of this study, CF patients were found to be at oral health risk due to the high prevalence of dental enamel defects. Oral health for CF children should be part of the multidisciplinary care.

Key words:Cystic fibrosis, oral health, teeth, United States.

Dental and periodontal manifestations in patients with cystic fibrosis - A systematic review

BACKGROUND

The oral cavity is an important reservoir of microorganisms and can be a potential source of infection of the respiratory tract in CF patients. The literature on the oral health does not explicitly determine dental problems in these patients. The aim of the study was to systematically review the studies relating to oral status in CF patients.

METHODS

A systematic review of papers published from 1997 to 2018 regarding oral status in CF children and adults, carried out in accordance with the Cochrane Collaboration guidelines.

RESULTS

The search resulted in 143 studies. Thirteen publications were included in the systematic review.

CONCLUSIONS

Effect of fluoride on salivary immunoglobulins and sialic acid

Objective:

The aim of our study was to evaluate the effect of fluoride on salivary immunoglobulin and sialic acid levels in children with dental fluorosis and healthy teeth who live in places with high fluoride concentration in drinking water.

Method:

Fifty-one (51) healthy children between 6 and 12 years old with no caries were randomly selected from primary schools enrolled in the dental-care program operated by the Department of Pediatric Dentistry. The children were divided into two groups: group I comprised 26 children with dental fluorosis [Thylstrup-Fejerskov Dental Fluorosis Index (TFI) = 4] who lived in Isparta (2.7-2.8 ppm), and group II consisted of 25 children without dental fluorosis who were born in low-fluoride areas and had lived in Isparta for only the previous two years. Stimulated and unstimulated saliva were collected and analyzed for fluoride, salivary immunoglobulins and sialic acid levels.

Results:

Sialic acid level was correlated negatively with age. Levels of secretory immunoglobulin A (sIgA) and secretory immunoglobulin G (sIgG) were higher in children with dental fluorosis compared with those in group II, although these differences were not significant.

Conclusion:

Increased sIgA and sIgG levels may arrest the progression of caries in subjects with dental fluorosis. Given the risks of dental fluorosis, further studies of the effects of different fluoride levels in drinking water on salivary composition of children with mixed dentition are needed to confirm the results of our study and to provide data for comparison.

Enterosalivary nitrate metabolism and the microbiome: Intersection of microbial metabolism, nitric oxide and diet in cardiac and pulmonary vascular health

Recent insights into the bioactivation and signaling actions of inorganic, dietary nitrate and nitrite now suggest a critical role for the microbiome in the development of cardiac and pulmonary vascular diseases. Once thought to be the inert, end-products of endothelial-derived nitric oxide (NO) heme-oxidation, nitrate and nitrite are now considered major sources of exogenous NO that exhibit enhanced vasoactive signaling activity under conditions of hypoxia and stress. The bioavailability of nitrate and nitrite depend on the enzymatic reduction of nitrate to nitrite by a unique set of bacterial nitrate reductase enzymes possessed by specific bacterial populations in the mammalian mouth and gut. The pathogenesis of pulmonary hypertension (PH), obesity, hypertension and CVD are linked to defects in NO signaling, suggesting a role for commensal oral bacteria to shape the development of PH through the formation of nitrite, NO and other bioactive nitrogen oxides. Oral supplementation with inorganic nitrate or nitrate-containing foods exert pleiotropic, beneficial vascular effects in the setting of inflammation, endothelial dysfunction, ischemia-reperfusion injury and in pre-clinical models of PH, while traditional high-nitrate dietary patterns are associated with beneficial outcomes in hypertension, obesity and CVD. These observations highlight the potential of the microbiome in the development of novel nitrate- and nitrite-based therapeutics for PH, CVD and their risk factors.