Protective effect of dexamethasone on 5-FU-induced oral mucositis in hamsters

Mechanisms of photobiomodulation therapy in treating and preventing antineoplastic-induced oral mucositis: a systematic review

PURPOSE

To conduct a systematic review of the mechanisms of photobiomodulation therapy (PBMT) for treating or preventing oral mucositis (OM) caused by antineoplastic therapy.

METHODS

Following PRISMA 2020 guidelines, a search was conducted in Medline, Latin American and Caribbean Health Sciences Literature (LILACS), Scientific Electronic Library Online (SciELO), and Bibliografia Brasileira de Odontologia from August to September 2023 using descriptors related to OM and laser therapy. Studies on the mechanisms of photobiomodulation in OM were included. Randomized (RCTs) or non-randomized trials from the past 10 years were reviewed. Risk of bias was assessed using RoB 2.0 and ROBINS-I tools.

RESULTS

A total of 355 studies was identified. After the screening, seven met the eligibility criteria. The RCTs showed a low risk of bias. PBMT reduced OM incidence in patients undergoing chemotherapy/radiotherapy. PBMT decreased pro-inflammatory cytokines (interleukin-6, tumor necrosis factor-α) and increased anti-inflammatory cytokines (interleukin-4, interleukin-10). It also modulated inflammatory mediators, enhancing the antioxidant enzyme superoxide dismutase and overexpressing genes for keratinocyte differentiation, aiding injury repair.

CONCLUSION

The findings suggested that the mechanism of action of PBMT in OM involves modulation of the inflammatory response, balancing oxygen reactive species generation, and expression of factors related to healing or repair. Further studies are needed to elucidate these mechanisms and optimize treatment protocols.

Topical Application of Dexamethasone-Loaded Core-Multishell Nanocarriers Against Oral Mucosal Inflammation

Topical treatment of oral inflammatory diseases is challenging due to the intrinsic physicochemical barriers of the mucosa and the continuous flow of saliva, which dilute drugs and limit their bioavailability. Nanocarrier technology can be an innovative approach to circumvent these problems and thus improve the efficacy of topical drug delivery to the mucosa. Core-multishell (CMS) nanocarriers are putative delivery systems with high biocompatibility and the ability to adhere to and penetrate the oral mucosa. Ester-based CMS nanocarriers release the anti-inflammatory compound dexamethasone (Dx) more efficiently than a conventional cream. Mussel-inspired functionalization of a CMS nanocarrier with catechol further improves the adhesion of the nanocarrier and may enhance the efficacy of the loaded drugs. In the present study, the properties of the ester-based CMS 10-E-15-350 nanocarrier (CMS-NC) are further evaluated in comparison to the catechol-functionalized variant (CMS-C0.08). While the mucoadhesion of CMS-NC is inhibited by saliva, CMS-C0.08 exhibits better mucoadhesion in the presence of saliva. Due to the improved adhesion properties, CMS-C0.08 loaded with dexamethasone (Dx-CMS-C0.08) shows a better anti-inflammatory effect than Dx-CMS-NC when applied dynamically. These results highlight the superiority of CMS-C0.08 over CMS-NC as an innovative drug delivery system (DDS) for the treatment of oral mucosal diseases.

Synergistic anti-tumorigenic effect of diosmetin in combination with 5-fluorouracil on human colon cancer xenografts in nude mice

5-Fluorouracil (5-FU) is frequently used to treat colorectal cancer (CRC), but its clinical application is limited by its toxicity. Natural compounds have been combined with chemotherapeutic drugs to reduce chemotherapy-related toxicity. Diosmetin, a natural flavonoid, has demonstrated anticancer effects against CRC. This study investigated diosmetin's potential in combination with 5-FU using a murine model of HCT-116 colon cancer xenografts in nu/nu nude mice. HCT-116 cells were injected into the right flanks of mice, and once tumors reached a size of 50 mm3, the mice were treated with diosmetin (100 mg/kg), 5-FU (30 mg/kg), or a combination of both at two dose levels (100 + 30 mg/kg and 50 + 15 mg/kg) for 4 weeks. Blood and tumors were collected on the final day for further analysis. Mice treated with the higher combination dose exhibited the smallest tumor volume (330.91 ± 88.49 mm3). Biochemistry and histology analysis showed no toxicity or abnormalities in the liver, kidney, and heart with the combination therapy. Immunohistochemistry results revealed a notable reduction in the proliferation marker (Ki67) and inflammation marker (TLR4) in tumors from high-dose combination-treated mice. Moreover, immunofluorescence data indicated increased levels of apoptotic markers (Bax, Caspase-3, p53, p21) and downregulation of anti-apoptotic protein (Bcl-2) in the high-dose combination group. The findings suggest that 100 mg/kg of diosmetin combined with 30 mg/kg 5-FU significantly reduced tumor volume and had a less toxic effect on the heart compared to 5-FU monotherapy.

Host derived macrophage migration inhibitory factor expression attenuates anti-tumoral immune cell accumulation and promotes immunosuppression in the tumor microenvironment of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is a significant public health concern worldwide. Immunomodulatory targets in the HNSCC tumor microenvironment are crucial to enhance the efficacy of HNSCC immunotherapy. Macrophage migration inhibitory factor (MIF) is a pro-inflammatory cytokine that has been linked to poor prognosis in many cancers, but the mechanistic role of MIF in HNSCC remains unclear. Using a murine orthotopic oral cancer model in Mif+/+ or Mif-/- mice, we determined the function of host derived MIF in HNSCC tumor development, metastasis as well as localized and systemic tumor immune responses. We observed that Mif-/- mice have decreased tumor growth and tumor burden compared to their wild-type counterparts. Flow cytometric analysis of immune populations within the primary tumor site revealed increased Th1 and cytotoxic T cell recruitment to the HNSCC tumor microenvironment. Within the tumors of Mif-/- mice, MIF deletion also enhanced the effector function of anti-tumoral effector CD8+ T cells as well as Th1 cells and decreased the accumulation of granulocytic myeloid derived suppressor cells (g-MDSCs) in the tumor microenvironment. Furthermore, MDSCs isolated from tumor bearing mice chemotactically respond to MIF in a dose dependent manner. Taken together, our results demonstrate a chemotactic and immunomodulatory role for host derived MIF in promoting HNSCC and suggest that MIF targeted immunomodulation is a promising approach for HNSCC treatment.

Anakinra and dexamethasone treatment of idarubicin-induced mucositis and diarrhoea in rats

Chemotherapy-induced mucositis, characterized by diarrhoea and villous atrophy, is a severe side effect contributing to reduced quality of life and premature death in cancer patients treated with cytostatics. Despite its high incidence, there is no effective supportive therapy available. The main objective of this study was to determine if the anti-inflammatory drugs anakinra and/or dexamethasone-which have different mechanisms-of-action-might be used to effectively treat idarubicin-induced mucositis in rats. Mucositis was induced through a single injection with 2 mg/kg idarubicin (with saline as control), followed by daily treatments of anakinra (100 mg/kg/day), dexamethasone (10 mg/kg/day) or both for 3 days. After 72 h, jejunal tissue was collected for morphological, apoptotic and proliferative analyses, and colonic faecal water content and body weight change were determined. The diarrhoea that was induced by idarubicin (from 63.5% to 78.6% water content in faeces) was completely reversed by anakinra alone, and the jejunal villus height reduction by 36% was prevented by a combination of anakinra and dexamethasone. Dexamethasone reduced apoptosis in the jejunal crypts, both alone and in combination with anakinra. These positive effects encouraged further investigations into the use of anakinra and dexamethasone as supportive therapies for chemotherapy-induced intestinal mucositis and diarrhoea.

Dexamethasone in preventive analgesia alleviates pain and complications after jaw cyst enucleation: a randomized controlled trial

Background

Dexamethasone is widely used in the prevention of postoperative complications in oral surgery and strengthening the analgesic effect after anesthesia, but the efficacy is controversial, and the relationship between postoperative complications and pain is still unclear. The purpose of this study was to evaluate the analgesic effect of dexamethasone in the treatment of jaw cyst and to explore the relationship between postoperative complications and pain.

Methods

We conducted a prospective, randomized, double-blind clinical trial. 120 patients were divided into two groups, dexamethasone group ( group D) and control group (Group C). All patients were given 0.02 mg·kg−1 of hydromorphone to relieve pain in advance at 10 min before the beginning of operation. Meanwhile, dexamethasone was injected 0.2 mg·kg−1 intravenously in group D and normal saline was injected in group C. The primary endpoint was pain intensity at 2 h, 6 h, 12 h, 24 h and 48 h after surgery. The secondary endpoints were the incidence and extent of complications after surgery, including facial swelling and trismus.

Results

Compared with group C, the visual analogue scale (VAS) scores and occurrence of painful event postoperatively in group D were significantly lower both at rest (P < 0.0001 and P = 0.0014) and during mobilization (P < 0.0001 both). The degree of facial swelling and trismus in group D were significantly lower than that in group C at 24 h (P < 0.0001 and P = 0.00022) and 48 h (P < 0.0001 and P = 0.00015) after surgery, but there was no difference at 6 h and 12 h (P = 0.137 and P = 0.083) after surgery. The C-reactive protein (CRP) level at 24 h after operation in group D was lower than group C (P = 0.012), but there was no significant difference in blood glucose concentration between the two groups (P = 0.608).

Conclusion

Dexamethasone can reduce the degree of facial swelling and trismus after jaw cyst surgery by inhibiting the production of inflammation, which alleviated the postoperative pain of patients significantly. In addition, it did not increase the risk of hyperglycemia.

Trial registration

This study was registered with the Chinese Clinical Trial Registry on May 07, 2020 (URL: http://www.chictr.org.cn/showproj.aspx?proj=53344. Registry number: ChiCTR2000032693). Registered on 07/05/2020.

In Vitro and In Vivo Cell-Interactions with Electrospun Poly (Lactic-Co-Glycolic Acid) (PLGA): Morphological and Immune Response Analysis

Random electrospun three-dimensional fiber membranes mimic the extracellular matrix and the interfibrillar spaces promotes the flow of nutrients for cells. Electrospun PLGA membranes were analyzed in vitro and in vivo after being sterilized with gamma radiation and bioactivated with fibronectin or collagen. Madin-Darby Canine Kidney (MDCK) epithelial cells and primary fibroblast-like cells from hamster’s cheek paunch proliferated over time on these membranes, evidencing their good biocompatibility. Cell-free irradiated PLGA membranes implanted on the back of hamsters resulted in a chronic granulomatous inflammatory response, observed after 7, 15, 30 and 90 days. Morphological analysis of implanted PLGA using light microscopy revealed epithelioid cells, Langhans type of multinucleate giant cells (LCs) and multinucleated giant cells (MNGCs) with internalized biomaterial. Lymphocytes increased along time due to undegraded polymer fragments, inducing the accumulation of cells of the phagocytic lineage, and decreased after 90 days post implantation. Myeloperoxidase⁺ cells increased after 15 days and decreased after 90 days. LCs, MNGCs and capillaries decreased after 90 days. Analysis of implanted PLGA after 7, 15, 30 and 90 days using transmission electron microscope (TEM) showed cells exhibiting internalized PLGA fragments and filopodia surrounding PLGA fragments. Over time, TEM analysis showed less PLGA fragments surrounded by cells without fibrous tissue formation. Accordingly, MNGC constituted a granulomatous reaction around the polymer, which resolves with time, probably preventing a fibrous capsule formation. Finally, this study confirms the biocompatibility of electrospun PLGA membranes and their potential to accelerate the healing process of oral ulcerations in hamsters’ model in association with autologous cells.

Network analysis and experimental pharmacology study explore the protective effects of Isoliquiritigenin on 5-fluorouracil-Induced intestinal mucositis

5-fluorouracil (5-FU) is one of the most widely used chemotherapy drugs for malignant tumors. However, intestinal mucositis caused by 5-FU is a severe dose-limiting toxic effect and even leads to treatment interruption. Isoliquiritigenin (ISL) is one of the main active compounds of licorice, which is a traditional Chinese herbal medicine commonly used in inflammation and gastrointestinal diseases. It is speculated that ISL have protective effects on intestinal mucositis. However, no such studies have been reported. Therefore, to investigate the impact of ISL on 5-Fu-induced intestinal mucositis, a strategy based on network prediction and pharmacological experimental validation was proposed in this study. Firstly, the targets and mechanism of ISL in alleviating 5-Fu-induced gastrointestinal toxicity were predicted by network analysis. And the results were further confirmed by molecular docking. Then, a mouse model of intestinal mucositis was established by intraperitoneal injection of 5-FU (384 μmol/kg) to verify the prediction of network analysis. The network analysis results suggested that PTGS2 (Prostaglandin G/H synthase 2) and NOS2 (Nitric oxide synthase, inducible) might be the critical targets of ISL for reducing the intestinal toxicity of 5-FU. In addition, KEGG and GO enrichment analysis revealed that the HIF-1, TNF, MAPK, IL-17, PI3K-Akt, Ras, NF-kappa B signaling pathway, and biological processes of the inflammatory response, apoptosis regulation, NO production and NF-kappa B transcription factor activity might be involved in the mechanism of ISL against intestinal mucositis. Subsequent animal experiments showed that ISL could reduce the weight loss, leukopenia and mucosal damage caused by 5-FU. Compared with the intestinal mucositis model, the protein expressions of PTGS2, NOS2, TNFα (Tumor necrosis factor-alpha) and NF-κB p65 (nuclear factor kappa-B P65) were decreased after ISL treatment. In conclusion, this study is the fist time to find that ISL can attenuate 5-FU-induced intestinal mucositis in mice. Its anti-mucositis effect may be through regulating TNF/NF-κB pathway and inhibiting inflammatory mediators PTGS2 and NOS2. It will provide a potential candidate for the prevention and treatment of chemotherapy-induced intestinal mucositis.

Expression Profiles of GILZ and Annexin A1 in Human Oral Candidiasis and Lichen Planus

Adrenal glands are the major source of glucocorticoids, but recent studies indicate tissue-specific production of cortisol, including that in the oral mucosa. Both endogenous and exogenous glucocorticoids regulate the production of several proteins, including the glucocorticoid-induced leucine zipper (GILZ) and Annexin A1, which play important roles in the regulation of immune and inflammatory responses. Common inflammation-associated oral conditions include lichen planus and candidiasis, but the status of GILZ and Annexin A1 in these human conditions remains to be established. Accordingly, archived paraffin-embedded biopsy samples were subjected to immunohistochemistry to establish tissue localization and profile of GILZ and Annexin A1 coupled with the use of hematoxylin–eosin stain for histopathological assessment; for comparison, fibroma specimens served as controls. Histopathological examination confirmed the presence of spores and pseudohyphae for oral candidiasis (OC) specimens and marked inflammatory cell infiltrates for both OC and oral lichen planus (OLP) specimens compared to control specimens. All specimens displayed consistent and prominent nuclear staining for GILZ throughout the full thickness of the epithelium and, to varying extent, for inflammatory infiltrates and stromal cells. On the other hand, a heterogeneous pattern of nuclear, cytoplasmic, and cell membrane staining was observed for Annexin A1 for all specimens in the suprabasal layers of epithelium and, to varying extent, for inflammatory and stromal cells. Semi-quantitative analyses indicated generally similar fractional areas of staining for both GILZ and Annexin A1 among the groups, but normalized staining for GILZ, but not Annexin A1, was reduced for OC and OLP compared to the control specimens. Thus, while the cellular expression pattern of GILZ and Annexin A1 does not differentiate among these conditions, differential cellular profiles for GILZ vs. Annexin A1 are suggestive of their distinct physiological functions in the oral mucosa.

Spatiotemporally dynamic therapy with shape-adaptive drug-gel for the improvement of tissue regeneration with ordered structure

A spatiotemporally dynamic therapy (SDT) is proposed as a powerful therapeutic modality that provides spatially dynamic responses of drug-carriers for adapting to the wound microenvironment. Herein, dynamic chitosan-poly (ethylene glycol) (CP) Schiff-base linkages are employed to perform SDT by directly converting a liquid drug Kangfuxin (KFX) into a gel formation. The obtained KFX-CP drug-gel with shape-adaptive property is used to treat a representative oral mucositis (OM) model in a spatiotemporally dynamic manner. The KFX-CP drug-gel creates an instructive microenvironment to regulate signaling biomolecules and endogenous cells behavior, thereby promoting OM healing by the rule of dynamically adjusting shape to fit the irregular OM regions first, and then provides space for tissue regeneration, over KFX potion control and the general hydrogel group of CP hydrogel and KFX-F127. Most interestingly, the regenerated tissue has ordered structure like healthy tissue. Therefore, the SDT provides a new approach for the design of next generation of wound dressing and tissue engineering materials.

Transcriptome sequencing and metabolome analysis reveal the mechanism of Shuanghua Baihe Tablet in the treatment of oral mucositis

Oral mucositis (OM) caused by cancer therapy is the most common adverse reaction in the radiotherapy of head and neck tumors. In severe cases, it can lead to the interruption of treatment, which affects the control of the disease and the quality of life. Shuanghua Baihe Tablet (SBT) is a traditional Chinese medicine (TCM) formula, which is administerd to treat OM in China. It has been clinically effective for more than 30 years, but the underlying mechanism is not completely understood. With the development of multiple omics, it is possible to explore the mechanism of Chinese herbal compound prescriptions. Based on transcriptomics and metabolomics, we explored the underlying mechanism of SBT in the treatment of OM. An OM model of rats was established by 5-FU induction, and SBT was orally administered at dosages of 0.75 and 3 g·kg^-1·d^-1. In order to search for SBT targets and related metabolites, the dysregulated genes and metabolites were detected by transcriptomics and metabolomics. Immune related indicators such as interleukin-17 (IL-17) and tumor necrosis factor-α (TNF-α) were detected by ELISA. Treg cell disorders was analyzed by flow cytometry. Our results showed that SBT significantly alleviated the symptoms of OM rats and the inflammatory infiltration of ulcer tissues. After SBT administration, inflammatory related metabolic pathways including linoleic acid metabolism, valine, leucine and isoleucine biosynthesis were significantly altered. Furthermore, the production of proinflammatory factors like IL-17 and TNF-α, were also dramatically reduced after SBT administration. Besides, the infiltration degree of Treg cells in the spleen of OM modeling rats was significantly improved by SBT administration, thus maintaining the immune balance of the body. The current study demonstrates that SBT regulates inoleic acid metabolism, glycerophospholipid metabolism and amino acid metabolism, and inhibits IL-17/TNF signal transduction to restore Treg and Th17 cell homeostasis in OM rats, thereby alleviating chemotherapy-induced OM.

Analgesic Mechanisms of Steroid Ointment against Oral Ulcerative Mucositis in a Rat Model

Despite the long history of use of steroid ointments for oral mucositis, the analgesic mechanism has not been fully elucidated. In this study, we examined the effects of triamcinolone acetonide (Tmc) on oral ulcerative mucositis-induced pain in conscious rats by our proprietary assay system. Based on evaluations of the physical properties and retention periods in the oral mucosa of human volunteers and rats, we selected TRAFUL^® ointment as a long-lasting base. In oral ulcerative mucositis model rats, TRAFUL^® with Tmc suppressed cyclooxygenase-dependent inflammatory responses with upregulations of glucocorticoid receptor-induced anti-inflammatory genes and inhibited spontaneous nociceptive behavior. When an ointment with a shorter residual period was used, the effects of Tmc were not elicited or were induced to a lesser extent. Importantly, TRAFUL^® with Tmc also improved oral ulcerative mucositis-induced mechanical allodynia, which has been reported to be independent of cyclooxygenase. Ca²⁺ imaging in dissociated trigeminal ganglion neurons showed that long-term preincubation with Tmc inhibited the hypertonic stimulation-induced Ca²⁺ response. These results suggest that the representative steroid Tmc suppresses oral ulcerative mucositis-induced pain by general anti-inflammatory actions and inhibits mechanical sensitivity in peripheral nerves. For drug delivery, long-lasting ointments such as TRAFUL^® are needed to sufficiently induce the therapeutic effects.

Anti-inflammatory effect of L-cysteine (a semi-essential amino acid) on 5-FU-induced oral mucositis in hamsters

Oral mucositis is an inflammation of the oral mucosa mainly resulting from the cytotoxic effect of 5-fluorouracil (5-FU). The literature shows anti-inflammatory action of L-cysteine (L-cys) involving hydrogen sulfide (H₂S). In view of these properties, we investigate the effect of L-cys in oral mucositis induced by 5-FU in hamsters. The animals were divided into the following groups: saline 0.9%, mechanical trauma, 5-FU 60-40 mg/kg, L-cys 10/40 mg and NaHS 27 µg/kg. 5-FU was administered on days 1st to 2nd; 4th day excoriations were made on the mucosa; 5th-6th received L-cys and NaHS. For data analysis, histological analyses, mast cell count, inflammatory and antioxidants markers, and immunohistochemistry (cyclooxygenase-2(COX-2)/inducible nitric oxide synthase (iNOs)/H₂S) were performed. Results showed that L-cys decreased levels of inflammatory markers, mast cells, levels of COX-2, iNOS and increased levels of antioxidants markers and H₂S when compared to the group 5-FU (p < 0.005). It is suggested that L-cys increases the H₂S production with anti-inflammatory action in the 5-FU lesion.

Mouthwash Containing Vitamin E, Triamcinolon, and Hyaluronic Acid Compared to Triamcinolone Mouthwash Alone in Patients With Radiotherapy-Induced Oral Mucositis: Randomized Clinical Trial

One of the most common side effects of radiotherapy in head and neck cancers is mucositis. Despite all the studies conducted on new therapies proposed for oral mucositis caused by radiation therapy, a single standard treatment strategy has not been developed yet. In the present study, for the first time, the effectiveness of the treatment with a combined mouthwash containing vitamin E (as an antioxidant), triamcinolone (as an anti-inflammatory agent) and hyaluronic acid (HA) (as a local reducer used for reducing the effects of ROS on the mucosa, with ameliorative effects (improving the healing process) compared to triamcinolone mouthwash alone was investigated in patients with radiotherapy-induced oral mucositis. This study was a randomized triple-blind clinical trial performed on 60 patients underwent radiotherapy on an outpatient basis. The combined mouthwash containing vitamin E, triamcinolone, and hyaluronic acid compared to triamcinolone mouthwash alone was prescribed for 4 weeks. The severity of oral mucositis was assessed based on the WHO classification and the intensity of pain was assessed using the numerical pain intensity scale. According to the analysis performed in the first, second, third and fourth weeks, the reduction of oral mucositis grade in the intervention group was significantly higher than in the comparison group. In the first, second, third, and fourth weeks, the reduction in pain intensity in the intervention group was significantly higher than in the comparison group (P < 0.001). The combined mouthwash containing vitamin E, hyaluronic acid and triamcinolone acetonide can be used as an effective treatment for oral mucositis caused by radiation therapy, which is probably the result of antioxidant, anti-inflammatory and improved healing process mechanisms due to the biological nature of the components of this mouthwash.

Effect of Dexamethasone-Loaded PLGA Nanoparticles on Oral Mucositis Induced by 5-Fluorouracil

Oral mucositis (OM) is characterized by the presence of severe ulcers in the oral region that affects patients treated with chemotherapy. It occurs in almost all patients who receive radiotherapy of the head and neck, as well as patients who undergo hematopoietic cell transplantation. The pathophysiology of OM is complex, and there is no effective therapy. The aim of this study was to evaluate the effect of dexamethasone-loaded poly(d,l-Lactic-co-glycolic) nanoparticles (PLGA-DEX NPs) on an OM model induced in hamsters. The NPs were synthesized using the emulsification-solvent evaporation method and were characterized by the size, zeta potential, encapsulation efficiency, atomic force microscopy, physicochemical stability, and the in vitro release. The OM was induced by the administration of 5-FU on the first and second days and mechanical trauma on the 4th day of the experiment. PLGA-DEX NPs were administered to treat OM. The animals were euthanized on the 10th day. Macroscopic and histopathological analyses were performed, measurement of malonaldehyde (MDA) and ELISA was used to determine the levels of IL-1β and TNF-α. Immunoexpressions of NF-κB, COX-2, and TGF-β were determined by immunohistochemistry, and qRT-PCR was used to quantify the gene expression of the GILZ, MKP1, and NF-κB p65. The PLGA-DEX NPs (0.1 mg/kg) significantly reduced macroscopic and histopathological scores, decreased MDA, TNF-α and IL-1β levels, immunostaining for NF-κB, COX-2, TGF-β, and suppressed NF-κB p65 mRNA expression, but increased GILZ and MKP1 expression.

Salivary alpha-1-antitrypsin and macrophage migration inhibitory factor may be potential prognostic biomarkers for oncologic treatment-induced severe oral mucositis

AIMS

Evaluate the abundance of the selected targets, alpha-1-antitrypsin (A1AT) and macrophage migration inhibitory factor (MIF), and correlate these findings with the risk of developing severe oral mucositis (OM).

MATERIALS AND METHODS

Head and neck squamous cell carcinoma (HNSCC) patients submitted to radiotherapy (RT) or chemoradiotherapy (CRT) were assessed. OM grade and pain were evaluated daily during treatment. Two protein targets, A1AT and MIF, were evaluated, using selected reaction monitoring-mass spectrometry (SRM-MS), in whole saliva, collected prior to oncologic treatment. The results obtained from the targeted proteomic analysis were correlated with OM clinical outcomes.

RESULTS

A total of 27 patients were included, of whom 21 (77.8%) had locally advanced disease (clinical stage III or IV). Most patients (70.4%) received CRT. OM grades 2 (40.8%) and 3 (33.3%) were the most prevalent during RT with a mean highest reported OM-related pain of 3.22 through the visual analogue scale (VAS). The abundance of A1AT and MIF correlated significantly with severe (grades 3 or 4, p < 0.02) compared with moderate-low (grades 1 or 2, p < 0.04) OM grade.

CONCLUSIONS

There is a correlation between the abundance of salivary A1AT and MIF and oncologic treatment-induced OM. The correlation of MIF expression with severe OM appears to be compatible with its physiological pro-inflammatory role. These results open up great possibilities for the use of salivary MIF and A1AT levels as prognostic markers for effective therapeutic interventions, such as photobiomodulation therapy, patient-controlled analgesia, or personalized medicaments.

Effect of Gold Nanoparticle on 5-Fluorouracil-Induced Experimental Oral Mucositis in Hamsters

BACKGROUND

Oral mucositis (OM) is a severe inflammation of the oral mucosal cells associated with chemotherapy and/or radiotherapy-induced toxicity, resulting in epithelial ulcers and higher risk of death from sepsis. The aim of the present study was to evaluate the nanoparticle (AuNp) effect on OM induced in hamsters.

MATERIALS AND METHODS

5-fluorouracil (5FU) was used on the first and second day of the experimental model in Golden sirian hamsters, and on the fourth day, mechanical trauma was applied to induce OM. The animals were divided into groups, i.e., polyvinylpyrrolidone (PVP), mechanical trauma (MT), 5FU, and groups treated with gold nanoparticles (AuNps) (62.5, 125, and 250 μg/kg). On the 10th day, animals were euthanized for macroscopic, histopathological, immunohistochemical, western blot, quantitative polymerase chain reaction (qRT-PCR), and AuNp quantification.

RESULTS

AuNp (250 μg/kg) reduced TNF-α, IL-1β, COX-2, NF-κB, TGF-β, and SMAD 2/3; increased glutathione levels; decreased the expression of Kelch ECH-associated protein 1 (KEAP1); and induced heme oxygenase 1 (HMOX-1) and NAD (P) H quinone oxidoreductase 1 (NQO1) genes.

CONCLUSIONS

AuNp (250 μg/kg) prevented 5-FU-induced OM in hamsters and improved the parameters of inflammation and oxidative stress.

Wound Healing Promoting Activity of Tonsil-Derived Stem Cells on 5-Fluorouracil-Induced Oral Mucositis Model

BACKGROUND

We first determined the efficacy of lesional injection of tonsil-derived MSCs (mesenchymal stem cells) for the treatment of 5-fluorouracil induced oral mucositis.

METHODS

Oral mucositis was induced in hamsters by administration of 5-fluorouracil (day 0, 2, 4) followed by mechanical trauma (day 1, 2, 4). The experimental groups included MT (mechanical trauma only), 5-FU + MT (mechanical trauma with 5-fluorouracil administration), TMSC (mechanical trauma with 5-fluorouracil administration, tonsil-derived mesenchymal stem cells injection), DEXA (mechanical trauma with 5-fluorouracil administration, dexamethasone injection), and saline (mechanical trauma with 5-fluorouracil administration, saline injection).

RESULTS

On day 10, gross and histologic analyses showed that nearly complete healing and epithelialization of the cheek mucosa of the TMSC group, whereas the other groups showed definite ulcerative lesions. Compared with the MT and DEXA groups, CD31 expression was greater in the TMSC group on days 10 and 14. Tendency towards a decrease in MMP2 expression with the time in the TMSC group was observed. In addition, the TMSC group showed higher expression of TGF-β, and NOX4 on day 10 compared with the other groups. Scratch assay demonstrated that the conditioned media harvested from tonsil-derived MSCs significantly increased migratory efficacy of NIH3T3 cells. Transwell assay showed that the preferential migration of tonsil-derived MSCs to the wound area.

CONCLUSION

Intralesional administration of tonsil-derived MSCs may accelerate wound healing of 5-fluorouracil induced oral mucositis by upregulating neovascularization and effective wound contraction. In addition, tonsil-derived MSCs might contribute to oral ulcer regeneration via the stimulation of fibroblast proliferation and migration.

Investigation of the Protective Effect of Nigella Sativa Oil in Cisplatin Induced Oral Mucositis: An Experimental Study

Objective

The aim of this experimental study was to investigate the histopathologic effect of Nigella Sativa oil (NSO) on cisplatin (Cis) induced oral mucositis (OM) in rats.

Methods

Twenty-four rats were divided into four equal groups. The animals in Group 1 and Group 2 were given 5 mg/kg intraperitoneal (ip) Cis systemically on the 1^st, 3^rd and 5^th days of the study. Additionally, 15 mL NSO were given to the rats in Group 2, with gavage feeding on days 1, 3, 5, 7, and 9. The animals in Group 3 were given per oral 15 ml NSO on days 1, 3, 5, 7 and 9. As the control group, Group 4 received a total of 15 mL 0.9% saline solution divided into 5 doses on days 1, 3, 5, 7 and 9 by oral gavage. On the 14^th day, animals were euthanized and buccal mucosa from both sides, including submucosal tissues, were excised and taken to histopathological examination.

Results

The mean mucosal thicknesses of the groups were 224.58 μm, 276.1 μm, 323.33 μm, and 331.33 μm, respectively for Groups 1, 2, 3, and 4 (p<0.05). When the degree of mucosal inflammation was examined, the most intense inflammation was detected in Group 1 and the least intense inflammation was in Group 4 (p<0.01). The degree of inflammation in Group 2 and Group 3 were similar to Group 4 (p>0.05).

Conclusion

According to the results of this study, NSO, for which anti-inflammatory and antioxidant properties have been shown in previous studies, may also be effective in preventing Cis-induced OM.

Amifostine reduces inflammation and protects against 5-fluorouracil-induced oral mucositis and hyposalivation

Oral mucositis (OM) is a common and dose-limiting side effect of cancer treatment, including 5-fluorouracil (5-FU) and radiotherapy. The efficacy of the therapeutic measures to prevent OM is limited and disease prevention is not fully observable. Amifostine is a cytoprotective agent with a described anti-inflammatory potential. It is clinically used to reduce radiotherapy and chemotherapy-associated xerostomia. This study investigated the protective effect of amifostine on an experimental model of OM. Hamsters were divided into six groups: saline control group (5 mL/kg), mechanical trauma (scratches) of the right cheek pouch; 5-FU (60 and 40 mg/kg, ip, respectively, administered on days 1 and 2); amifostine (12.5, 25, or 50 mg/kg) + 5-FU + scratches. Salivation rate was assessed and the animals were euthanized on day 10 for the analysis of macroscopic and microscopic injury by scores. Tissue samples were harvested for the measurement of neutrophil infiltration and detection of inflammatory markers by ELISA and immunohistochemistry. 5-FU induced pronounced hyposalivation, which was prevented by amifostine (P<0.05). In addition, 5-FU injection caused pronounced tissue injury accompanied by increased neutrophil accumulation, tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β) tissue levels, and positive immunostaining for TNF-α, IL-1β, and inducible nitric oxide synthase (iNOS). Interestingly, amifostine prevented the inflammatory reaction and consequently improved macroscopic and microscopic damage (P<0.05 vs 5-FU group). Amifostine reduced inflammation and protected against 5-FU-associated oral mucositis and hyposalivation.

Anthocyanins Extracted from Oryza sativa L. Prevent Fluorouracil-Induced Nuclear Factor-κB Activation in Oral Mucositis: In Vitro and In Vivo Studies

This study aims to investigate the immunomodulatory effect of anthocyanins (ANTs) from Oryza sativa L. extracts on 5-fluorouracil (5-FU)-induced oral mucositis, using a rat model and oral keratinocytes. ANTs were detected by high-performance liquid chromatography (HPLC)-electrospray ionization mass spectrometry. Animals were randomly given varying doses of ANT-rich extract treatment (500 mg/kg and 1000 mg/kg) in the absence or presence of 5-FU-induced mucositis. Buccal mucosae were photographed and scored for macroscopic analysis and incisional biopsies of cheek pouches were collected for microscopic examination of oral mucositis. 5-FU caused marked hemorrhage, extensive ulcerations and abscesses compared to non-treated animals with slight erythema. Histologically, a loss of collagen bundles and inflammatory cell infiltrates was observed. After 29 days of ANT treatment, lesions resolved, and abundant collagen fibers were evident in the lamina propria. Buccal mucosa of 5-FU-injected rats showed increased Nuclear factor-kappa B (NF-κB) p50 and p65 in oral keratinocytes. The administration of ANT reduced NF-κB-positive cells in 5-FU rats (p < 0.001) compared to the non-treatment group. In oral keratinocytes, ANT treatment significantly restored 5-FU-induced growth inhibition and impaired the nuclear accumulation of NF-κB p50 and p65. Our study demonstrated that ANT from Oryza sativa L. exhibited effective anti-inflammatory properties against 5-FU-induced oral mucositis by inhibiting NF-κB activation.

Telmisartan Modulates the Oral Mucositis Induced by 5-Fluorouracil in Hamsters

Oral mucositis (OM) is a common adverse effect resulting from cancer therapy. The OM it has implications that may compromise oncologic treatment and decrease the patient's quality of life. The therapeutic options to prevent or treat the symptoms of OM are scarce; there is no effective therapy that improves the symptoms. Based on the need for further research for the treatment of OM, the present study objective was to evaluate the effect of telmisartan (TELM) on the OM induced by 5-fluorouracil (5-FU), using as animal model Golden Syrian hamsters. 5-FU followed by mechanical trauma on day 4 was used to induce OM in hamsters. Euthanasia occurred on the day 10. The experiments were constituted by the groups saline, mechanical trauma, 5-FU, and TELM in three doses (1, 5, or 10 mg/kg). Macroscopic, histopathological, and immunohistochemical analyses as well as immunofluorescence experiments were performed on the oral mucosa of the animals. The samples also were used for analysis enzyme-linked immunosorbent assays and quantitative real-time polymerase chain reactions (qPCR). TELM (5 or 10 mg/kg) was able to reduce the inflammatory ulceration and infiltration in the oral mucosa of the animals, decreasing the levels of the cytokines TNF-α and IL-1β. These treatments was minimize the immunostaining for cyclooxygenase-2, matrix metalloproteinase-9, transforming growth factor-β, and smad 2/3. The nuclear transcription factor kappa B (NFκB) p65 and inducible nitric oxide synthase were reduced in the oral mucosa. Finally, TELM (10 mg/kg) increased the PPARγ gene expression and reduced STAT1 and NFκB p65 gene expression relative to the 5-FU group. Therefore, TELM prevents the OM produced by 5-FU on animal model.

Phase II investigational oral drugs for the treatment of radio/chemotherapy induced oral mucositis

INTRODUCTION

Oral mucositis is a significant unmet clinical need for many cancer patients. The biological complexity of mucositis' pathogenesis provides a number of mechanistic targets suitable as pharmacologic targets. The diversity of targets has stimulated drug development in search of an effective intervention. In this paper, we review a range of agents that are currently being evaluated.

AREAS COVERED

Drugs for management of oral mucositis vary in formulation, route of administration and biological target. Most propose to interrupt the initiation of injury by suppressing activation of the innate immune response or countering oxidative stress, or minimizing downstream inflammatory responses. Overwhelmingly, the population most studied is patients being treated with concomitant chemoradiation for cancers of the head and neck as this is the cohort that most consistently suffers severe mucositis for long periods of time. The Phase 2 pipeline is robust. Preliminary data reported for a number of agents is optimistic. Genomics may be important in interpreting and comparing responses to agents across widely demographically diverse populations.

EXPERT OPINION

Oral mucositis remains a significant toxicity for patients undergoing cancer treatment. Incremental reports of successes have been noted for a number of targeted agents.