Hyposalivation due to chemotherapy exacerbates oral ulcerative mucositis and delays its healing

Addressing mucosal ulcers during orthodontic treatment: An urgent call for preventive strategies

Mucosal ulcers are a common yet often overlooked complication during orthodontic treatment, significantly impacting patient comfort and compliance. This letter aims to highlight the prevalence, potential causes, and management strategies for mucosal ulcers in orthodontic patients. By reviewing recent literature and clinical observations, we underscore the necessity for proactive measures and tailored interventions to mitigate the incidence and severity of these lesions. Emphasizing the role of patient education and the use of protective devices, we call for a multidisciplinary approach to enhance patient care and treatment outcomes. This discussion is particularly relevant in the context of evolving orthodontic techniques and materials, which necessitate continuous adaptation of clinical practices to ensure patient safety and well-being.

Recent advances in the treatment of oral ulcerative mucositis from clinical and basic perspectives

BACKGROUND

Oral ulcerative mucositis (OUM) is common in patients with cancer, particularly in those undergoing chemoradiation therapy. The effective management of OUM is crucial for continuous cancer care and patient well-being. Recent studies have advanced our understanding of the causes, leading to clinical trials toward novel treatments. This review focuses on the contemporary therapeutic landscape, and provides the latest insights into the mechanisms of mucosal healing and pain.

HIGHLIGHTS

Management strategies for OUM in patients with cancer include maintaining good oral hygiene, reducing mucosal irritation against radiation, and using various topical analgesic treatments, including herbal medicines. However, the current management practices have limitations that necessitate the development of more efficacious and novel treatments. Molecular research on transient receptor potential (TRP) channels in the oral mucosa is crucial for understanding the mechanisms of wound healing and pain in patients with OUM. Targeting TRPV3 and TRPV4 can enhance wound healing through re-epithelialization. The suppression of TRPV1, TRPA1, and TRPV4 may be effective in alleviating OUM-induced pain.

CONCLUSION

Research advancements have improved our understanding and potentially led to novel treatments that offer symptomatic relief. This progress highlights the importance of collaborations between clinical researchers and scientists in the development of innovative therapies.

Protective Effect of Electroacupuncture on Chemotherapy-Induced Salivary Gland Hypofunction in a Mouse Model

Radiotherapy and chemotherapy can impair salivary gland (SG) function, which causes xerostomia and exacerbate other side effects of chemotherapy and oral infection, reducing patients' quality of life. This animal study aimed to assess the efficacy of electroacupuncture (EA) as a means of preventing xerostomia induced by 5-fluorouracil (5-FU). A xerostomia mouse model was induced via four tail vein injections of 5-FU (80 mg/kg/dose). EA was performed at LI4 and LI11 for 7 days. The pilocarpine-stimulated salivary flow rate (SFR) and salivary glands weight (SGW) were recorded. Salivary immunoglobulin A (SIgA) and lysozyme were determined via enzyme-linked immunosorbent assay (ELISA). SG was collected for hematoxylin and eosin staining to measure acini number and acinar cell size. Tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and aquaporin 5 (AQP5) mRNA expressions in SG were quantified via RT-qPCR. 5-FU caused significant decreases in SFR, SGW, SIgA, lysozyme, AQP5 expression, and acini number, while TNF-α and IL-1β expressions and acinar cell size were significantly increased. EA treatment can prevent 5-FU damage to the salivary gland, while pilocarpine treatment can only elevate SFR and AQP5 expression. These findings provide significant evidence to support the use of EA as an alternative treatment for chemotherapy-induced salivary gland hypofunction and xerostomia.

Xerostomia aggravates ligation-induced peri-implantitis: A preclinical in vivo study

OBJECTIVES

Previous studies have indicated that xerostomia is a critical factor affecting periodontitis; nonetheless, it is controversial whether xerostomia impairs peri-implant tissue. The objective of this experimental study was to evaluate the effect of xerostomia on the peri-implant hard and soft tissues in the rat model.

MATERIALS AND METHODS

Implants were placed in bilateral maxillae of male Wistar rats. The animals underwent submandibular and sublingual gland resection on both sides (DRY group) or sham operation (CTR group). Silk ligatures were placed around one side of abutments, which were randomly selected in each animal. The effects of xerostomia were assessed using micro-CT, histological analysis, real-time PCR, and 16S rRNA-based metagenomic analysis.

RESULTS

Ligation with silk thread caused bone resorption around implants. Although xerostomia itself did not induce bone resorption, it significantly enhanced silk ligature-mediated bone resorption around implants. Histological analysis and real-time PCR indicated that xerostomia induced inflammation and osteoclastogenesis around implants with silk ligatures. Furthermore, it altered the microbiota of the plaque on the silk thread around implants.

CONCLUSION

Xerostomia accelerates mucosal inflammation and osteoclastogenesis, which aggravates bone resorption around implants.

Flavor alterations in cancer treatment: Extrinsic factors as a means of augmentation

Flavor, comprising taste, smell and somatosensory inputs, is commonly altered in patients undergoing chemotherapy resulting in malnutrition leading to cachexia. A narrative review considered taste and smell alterations associated with malignancies treated using chemotherapy and the various interventions proffered to lessen alterations. Many of the currently used interventions directed towards enhancing intrinsic factors of food appeared ineffective in encouraging intake of adequate nutrition to ward off complications of malnutrition. Counselling is used in some cases with positive results. The use of extrinsic influences commensurate with the principles of food behavior and gastronomy are considered as a means of providing purpose to patients to accommodate flavor loss which when integrated with counseling and appropriate intrinsic factors are potentially a means of curtailing malnutrition and enhancing the psychological status of the patient. The close association between the cephalic phase responses (CPRs) and the control of eating and digestive behaviors is multifaceted, and when the influences of taste and smell are diminished, other contributing factors guiding CPRs may compensate a deficit. The need for the application of a consistent lexicon is essential when describing taste and smell alterations.

LFchimera: a synthetic mimic of the two antimicrobial domains of bovine lactoferrin

Saliva is essential for the maintenance of oral health. When salivary flow is impaired, the risk of various oral diseases such as caries and candidiasis increases drastically. Under healthy conditions, saliva provides effective protection against microbial colonization by the collaborative action of numerous host-defense molecules. This review describes how saliva has been the guideline for the design and characterization of a heterodimeric antimicrobial construct called LFchimera. This construct mimics the helical parts of two antimicrobial domains in the crystal structure of bovine lactoferrin. It shows high antimicrobial activity against a broad spectrum of Gram-positive and Gram-negative bacteria, fungi, and parasites including biowarfare agents such as Bacillus anthracis, Burkholderia pseudomallei, and Yersinia pestis. Further, sublethal concentrations of LFchimera inhibited biofilm formation, the invasiveness of HeLa cells by Yersinia spp., and prevented haemolysis of enteropathogenic Escherichia coli, demonstrating the versatility of these peptides.

Expression of Ascorbate Peroxidase Derived from Cyanidioschyzon merolae in Mammalian Cells

BACKGROUND/AIM

Ascorbate peroxidase (APX) derived from Cyanidioschyzon merolae, a primitive red alga living in high temperature and acidic environments, has greater anti-oxidative capacity than similar peroxidases occurring in other plants. In the present study, we examined whether expression of Cyanidioschyzon merolae-derived APX (cAPX) in mammalian cells increases cellular anti-oxidative capacity.

MATERIALS AND METHODS

The cAPX gene was introduced into the mouse fibroblast-like cell line C3H10T1/2. Production of reactive oxygen species (ROS) and/or cell viability was assessed after heat, H₂O₂ and acid stimulation.

RESULTS

Heat and H₂O₂ stimulation resulted in ROS production. cAPX-expressing cells were more tolerant to oxidative stress induced by heat, H₂O₂ and acid stimulations than control cells lacking cAPX.

CONCLUSION

Introduction of cAPX increases the anti-oxidative capacity in mammalian cells.

Oral mucositis

Oral mucositis is one of the most common complications of cancer therapy. It is a nonhematologic complication of cytotoxic chemotherapy and radiotherapy and reduces the quality of life. It is estimated that 40% the cases on standard chemotherapy may develop oral mucositis. Patients receiving radiation, especially in the cases of head and neck cancer, have 30%-60% chances of developing mucositis. Chemotherapy and radiotherapy interfere with the normal turnover of epithelial cells, leading to mucosal injuries. These injuries can also occur due to indirect invasion of Gram negative bacteria and fungi as most of the chemo-therapeutic agents will cause neutropenia and will give a favorable environment for the development of mucositis. The patient-related factors are also responsible for developing mucositis in chemo-induced and radiation-induced mucositis. Poor oral hygiene may also be responsible for bacterial super infection followed by chemotherapy. Mucositis is of two kinds: direct and indirect mucositis. Direct mucositis - The epithelial cells of the oral mucosa undergo rapid turnover in usually 7-14 days due to which these cells are more susceptible to the effect of the cytotoxic therapy which results in oral mucositis. Indirect mucositis - it can develop due to the infection caused by Gram-negative bacteria and fungal infection. There will be a greater risk for oral infection due to neutropenia. The onset of mucositis secondary to mylo-suppression varies depending upon the timing of the neutrophil count associated with chemotherapy agents but they typically develop around 10-21 days after chemotherapy administration.