Carbonic Anhydrase II Activators in Osteopetrosis Treatment: A Review.

Osteopetrosis is a rare hereditary illness generated by failure in osteoclasts resulting in elevated bone densities. Patients with osteopetrosis possess several complications, like dental caries, earlier teeth loss, delayed eruption, malformed crowns and roots, and lamina dura thickening. Since deficiency of carbonic anhydrase II is a major cause behind osteopetrosis, carbonic anhydrase II activators have a large number of applications in osteopetrosis treatment. There is a lack of a comprehensive review on osteopetrosis, pathogenesis of dental abnormalities, and the role of carbonic anhydrase II activators in osteopetrosis treatment. To address this research gap, the authros perfomed a comprehensive review on osteopetrosis and its types, pathogenesis of dental abnormalities, and the role of carbonic anhydrase II activators in osteopetrosis treatment. A brief introduction to the pathogenesis of dental abnormalities and regeneration is provided in this survey. A discussion of types of osteopetrosis depending on genetic inheritance, such as autosomal dominant, autosomal recessive, and X-linked inheritance osteopetrosis, is presented in this survey. The paper also focuses on the importance of carbonic anhydrase II activators as a potential drug therapy for dental osteopetrosis. In addition, a brief note on the role of azole and fluconazole in treating osteopetrosis is given. Finally, future directions involving gene therapy for dental osteopetrosis are described.

Fluconazole-Induced Protein Changes in Osteogenic and Immune Metabolic Pathways of Dental Pulp Mesenchymal Stem Cells of Osteopetrosis Patients.

Osteopetrosis is a rare inherited disease caused by osteoclast failure, resulting in increasing bone density in humans. Patients with osteopetrosis possess several dental and cranial complications. Since carbonic anhydrase II (CA-II) deficiency is a major cause of osteopetrosis, CA-II activators might be an attractive potential treatment option for osteopetrosis patients. We conducted comprehensive label-free quantitative proteomics analysis on Fluconazole-treated Dental Pulp Mesenchymal Stem/Stromal Cells from CA-II-Deficient Osteopetrosis Patients. We identified 251 distinct differentially expressed proteins between healthy subjects, as well as untreated and azole-treated derived cells from osteopetrosis patients. Twenty-six (26) of these proteins were closely associated with osteogenesis and osteopetrosis disease. Among them are ATP1A2, CPOX, Ap2 alpha, RAP1B and some members of the RAB protein family. Others include AnnexinA1, 5, PYGL, OSTF1 and PGAM4, all interacting with OSTM1 in the catalytic reactions of HCO3 and the Cl- channel via CAII regulation. In addition, the pro-inflammatory/osteoclast regulatory proteins RACK1, MTSE, STING1, S100A13, ECE1 and TRIM10 are involved. We have identified proteins involved in osteogenic and immune metabolic pathways, including ERK 1/2, phosphatase and ATPase, which opens the door for some CA activators to be used as an alternative drug therapy for osteopetrosis patients. These findings propose that fluconazole might be a potential treatment agent for CAII- deficient OP patients. Altogether, our findings provide a basis for further work to elucidate the clinical utility of azole, a CA activator, as a therapeutic for OP.

Prevalence and risk factors of oral mucositis in paediatric patients undergoing haematopoietic stem cell transplantation.

BACKGROUND: A complete understanding of oral mucositis (OM) is crucial to develop appropriate interventions to aid in the successful overall health outcome of paediatric patients undergoing haematopoietic stem cell transplantation (HSCT). AIMS: This study aimed at determining the prevalence and severity of OM and at identifying the predictive factors that might aggravate OM at one-week, two-week and three-week post-HSCT. METHODS: This retrospective, hospital-based study reviewed the medical records of 170 paediatric patients, summarising the patients' characteristics using descriptive statistics. Binary logistic regression was used to identify factors associated with the development of OM. RESULTS: At one-week post-HSCT, 41% of 140 patients (n = 49) had developed OM, this was reduced at two-week (n = 36, 33%) and three-week (n = 13, 19%) post-HSCT. Univariate logistic regression revealed that patients with cancer (OR = 0.16, 95% CI = 0.05-0.54; p-value = .003) had a significantly lower prevalence of OM. Younger patients with an average age of 7.9 years old (OR = 0.85, 95% CI = 0.75-0.97; p-value = 0.013) and the presence of GvHD (OR = 2.37, 95% CI = 1.03-5.45, p-value = 0.042) were significantly related to a higher prevalence of OM. Multivariable logistic regression confirmed that the risk of OM is lower in patients with cancer compared to those with immunodeficiency syndromes or hereditary blood diseases (OR = 0.18, 95% CI = 0.04-0.77; p-value = .021). CONCLUSIONS: This study identified a significantly lower prevalence of OM in patients with cancer compared to other conditions and that young recipients and those who developed GvHD were more likely to have OM.

Proteomic Profiling of the First Human Dental Pulp Mesenchymal Stem/Stromal Cells from Carbonic Anhydrase II Deficiency Osteopetrosis Patients.

Osteopetrosis is a hereditary disorder characterized by sclerotic, thick, weak, and brittle bone. The biological behavior of mesenchymal cells obtained from osteopetrosis patients has not been well-studied. Isolated mesenchymal stem/stromal cells from dental pulp (DP-MSSCs) of recently extracted deciduous teeth from osteopetrosis (OP) patients and healthy controls (HCs) were compared. We evaluated whether the dental pulp of OP patients has a population of MSSCs with similar multilineage differentiation capability to DP-MSSCs of healthy subjects. Stem/progenitor cells were characterized using immunohistochemistry, flow cytometry, and proteomics. Our DP-MSSCs were strongly positive for CD44, CD73, CD105, and CD90. DP-MSSCs obtained from HC subjects and OP patients showed similar patterns of proliferation and differentiation as well as gene expression. Proteomic analysis identified 1499 unique proteins with 94.3% similarity in global protein fingerprints of HCs and OP patients. Interestingly, we observed subtle differences in expressed proteins of osteopetrosis disease-related in pathways, including MAPK, ERK 1/2, PI3K, and integrin, rather than in the stem cell signaling network. Our findings of similar protein expression signatures in DP-MSSCs of HC and OP patients are of paramount interest, and further in vivo validation study is needed. There is the possibility that OP patients could have their exfoliating deciduous teeth banked for future use in regenerative dentistry.

The efficacy of two different oral hygiene regimens on the incidence and severity of oral mucositis in pediatric patients receiving hematopoietic stem cell transplantation: A prospective interventional study.

AIMS: This prospective interventional study aimed to assess the efficacy of supersaturated calcium phosphate rinse and the use of an extra-soft toothbrush twice a day when added to the existing oral hygiene protocol regimen (0.12% chlorhexidine gluconate + 3% sodium bicarbonate + nystatin 5000 U/mL) in reducing the severity of oral mucositis among pediatric patients receiving chemotherapy for the hematopoietic stem cell transplant. METHODS: Forty-five patients that received chemotherapy for the hematopoietic stem cell transplant were randomly allocated to three groups of 15 patients each. Group A was advised to follow the existing oral hygiene protocol regimen (Control), group B was advised to brush their teeth twice daily using an extra-soft toothbrush and to follow the control regimen, and lastly group C was advised to use supersaturated calcium phosphate rinse and to follow the control regimen. Oral mucositis was recorded according to World Health Organization criteria from the day of admission (day 1) to the day of discharge (day 28). The incidence of oral mucositis between the three groups was compared using the Kruskall-Wallis test while the severity of oral mucositis between the three groups was compared using a one-way ANOVA test. RESULTS: The results of the study showed no significant difference in the incidence of oral mucositis between the three groups; however, there was a lower severity of oral mucositis in the supersaturated calcium phosphate rinse group when compared to the control group or the group who used an extra-soft toothbrush with the control regimen. CONCLUSION: Although marginally fewer cases and lower severity of oral mucositis was observed in the group using supersaturated calcium phosphate rinse, the lack of statistical significance suggests that the evidence for their use is not conclusive. The results of this study also showed that the introduction of an extra-soft toothbrush into the oral hygiene regimen did not significantly reduce the incidence of oral mucositis and may actually be responsible for an increase in the severity of oral mucositis.

Oral and dental management of people with myelodysplastic syndromes and acute myeloid leukemia: A systematic search and evidence-based clinical guidance.

AIMS: To systematically search all studies that discussed dental procedures in patients diagnosed with myelodysplastic syndromes (MDS) and/or acute myeloid leukemia (AML) and to provide an evidence-based clinical guidance on oral and dental management of people with MDS and/or AML. METHODS: The systematic search followed the Preferred Reporting Item for Systematic Review and Meta-analyses Protocols (PRISMA-P) guideline. Two databases systems were used (MEDLINE and EMBASE). PROSPERO was searched for ongoing or recently completed systematic reviews. The International Clinical Trials Registry Platform Search was searched for ongoing or recently completed trials. Level of evidence was evaluated based on the Oxford Level of Evidence. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to summarize the evidence. RESULTS: Only 18 articles were selected and included in data synthesis and analysis. The level of evidence and recommendation ranged from 1 to 5 and A to D, respectively. CONCLUSIONS: All the included studies in the data synthesis (n = 18) showed no specific guidelines were followed; however, all reflected the importance of liaison with the patient's hematoncologist at all stages of MDS and/or AML therapy. RECOMMENDATIONS: Oral and dental assessment is crucial prior to MDS therapy to help reduce anticipated complications. Dental treatment prior to hematopoietic stem cell transplantation and/or active stage of MDS therapy is tricky and always required liaison with the hematoncologist. MDS can progress to AML; hence, dental care providers are in a good position to spot any changes and refer early to the hematoncologist for further assessment.