HMGB1 Promotes Intraoral Palatal Wound Healing through RAGE-Dependent Mechanisms

HMGB1 Accelerates Wound Healing by Promoting the Differentiation of Epidermal Stem Cells via the "HMGB1-TLR4-Wnt/Notch" Axis

Objective: Impairments in the differentiation and migratory capacity of epidermal stem cells (ESCs) are pivotal factors contributing to delayed wound healing. High mobility group box1 (HMGB1) has recently emerged as a potential target for tissue repair. Therefore, we aimed to investigate the role and molecular mechanisms of HMGB1 in ESCs during the wound-healing process. Approach: Initially, we examined the expression of HMGB1 and the differentiation of ESCs in normal skin, normal wounds and chronic wounds. Then, we assessed the ESC migration and differentiation, and the key markers in the Wnt/Notch signaling pathways, after treatment of HMGB1 and inhibitor, and the knockdown of toll-like receptor 4 (TLR4), using scratch assay, qPCR, western blotting, and immunofluorescence. Finally, we conducted mice models to analyze the healing rates and quality in vivo. Results: HMGB1 was decreased across all epidermal layers, and the differentiation of ESCs was hindered in diabetic foot ulcer. In vitro, HMGB1 enhanced both the migration and differentiation of ESCs while stimulating the expression of the Wnt/Notch pathway within ESCs. However, the downregulation of TLR4 negated these effects. Finally, our in vivo experiments provided evidence that HMGB1 facilitates wound healing and epidermis differentiation via TLR4 and Wnt/Notch signaling pathways. Innovation: This study innovatively introduces HMGB1 as a novel target for skin wound healing and elucidates its mechanisms of action. Conclusions: HMGB1 accelerated wound healing by promoting the differentiation of epidermal stem cells through the "HMGB1-TLR4-Wnt/Notch" axis, which reveals a new potential mechanism and target to expedite wound healing.

The RAGE Pathway in Skin Pathology Development: A Comprehensive Review of Its Role and Therapeutic Potential

The receptor for advanced glycation end-products (RAGE), a member of the immunoglobulin superfamily, is expressed in various cell types and mediates cellular responses to a wide range of ligands. The activation of RAGE triggers complex signaling pathways that drive inflammatory, oxidative, and proliferative responses, which are increasingly implicated in the pathogenesis of skin diseases. Despite its well-established roles in conditions such as diabetes, cancer, and chronic inflammation, the contribution of RAGE to skin pathologies remains underexplored. This review synthesizes current findings on RAGE's involvement in the pathophysiology of skin diseases, including conditions such as psoriasis, atopic dermatitis, and lichen planus, focusing on its roles in inflammatory signaling, tissue remodeling, and skin cancer progression. Additionally, it examines RAGE-modulating treatments investigated in dermatological contexts, highlighting their potential as therapeutic options. Given RAGE's significance in a variety of skin conditions, further research into its mediated pathways may uncover new opportunities for targeted interventions in skin-specific RAGE signaling.

Analysis of Crude, Diverse, and Multiple Advanced Glycation End-Product Patterns May Be Important and Beneficial

Lifestyle-related diseases (LSRDs), such as diabetes mellitus, cardiovascular disease, and nonalcoholic steatohepatitis, are a global crisis. Advanced glycation end-products (AGEs) have been extensively researched because they trigger or promote LSRDs. Recently, techniques such as fluorimetry, immunostaining, Western blotting, slot blotting, enzyme-linked immunosorbent assay, gas chromatography-mass spectrometry, matrix-assisted laser desorption-mass spectrometry (MALDI-MS), and electrospray ionization-mass spectrometry (ESI-MS) have helped prove the existence of intra/extracellular AGEs and revealed novel AGE structures and their modifications against peptide sequences. Therefore, we propose modifications to the existing categorization of AGEs, which was based on the original compounds identified by researchers in the 20th century. In this investigation, we introduce the (i) crude, (ii) diverse, and (iii) multiple AGE patterns. The crude AGE pattern is based on the fact that one type of saccharide or its metabolites or derivatives can generate various AGEs. Diverse and multiple AGE patterns were introduced based on the possibility of combining various AGE structures and proteins and were proven through mass analysis technologies such as MALDI-MS and ESI-MS. Kampo medicines are typically used to treat LSRDs. Because various compounds are contained in Kampo medicines and metabolized to exert effects on various organs or tissues, they may be suitable against various AGEs.

Biomaterials derived from hard palate mucosa for tissue engineering and regenerative medicine

Autologous materials have superior biosafety and are widely used in clinical practice. Due to its excellent trauma-healing ability, the hard palate mucosa (HPM) has become a hot spot for autologous donor area research. Multiple studies have conducted an in-depth analysis of the healing ability of the HPM at the cellular and molecular levels. In addition, the HPM has good maneuverability as a donor area for soft tissue grafts, and researchers have isolated various specific mesenchymal stem cells (MSCs) from HPM. Free soft tissue grafts obtained from the HPM have been widely used in the clinic and have played an essential role in dentistry, eyelid reconstruction, and the repair of other specific soft tissue defects. This article reviews the advantages of HPM as a donor area and its related mechanisms, classes of HPM-derived biomaterials, the current status of clinical applications, challenges, and future development directions.

Novel In Vitro Assay of the Effects of Kampo Medicines against Intra/Extracellular Advanced Glycation End-Products in Oral, Esophageal, and Gastric Epithelial Cells

Kampo medicines are Japanese traditional medicines developed from Chinese traditional medicines. The action mechanisms of the numerous known compounds have been studied for approximately 100 years; however, many remain unclear. While components are normally affected through digestion, absorption, and metabolism, in vitro oral, esophageal, and gastric epithelial cell models avoid these influences and, thus, represent superior assay systems for Kampo medicines. We focused on two areas of the strong performance of this assay system: intracellular and extracellular advanced glycation end-products (AGEs). AGEs are generated from glucose, fructose, and their metabolites, and promote lifestyle-related diseases such as diabetes and cancer. While current technology cannot analyze whole intracellular AGEs in cells in some organs, some AGEs can be generated for 1-2 days, and the turnover time of oral and gastric epithelial cells is 7-14 days. Therefore, we hypothesized that we could detect these rapidly generated intracellular AGEs in such cells. Extracellular AEGs (e.g., dietary or in the saliva) bind to the receptor for AGEs (RAGE) and the toll-like receptor 4 (TLR4) on the surface of the epithelial cells and can induce cytotoxicity such as inflammation. The analysis of Kampo medicine effects against intra/extracellular AGEs in vitro is a novel model.

Wound healing dynamics, morbidity, and complications of palatal soft-tissue harvesting

Palatal-tissue harvesting is a routinely performed procedure in periodontal and peri-implant plastic surgery. Over the years, several surgical approaches have been attempted with the aim of obtaining autogenous soft-tissue grafts while minimizing patient morbidity, which is considered the most common drawback of palatal harvesting. At the same time, treatment errors during the procedure may increase not only postoperative discomfort or pain but also the risk of developing other complications, such as injury to the greater palatine artery, prolonged bleeding, wound/flap sloughing, necrosis, infection, and inadequate graft size or quality. This chapter described treatment errors and complications of palatal harvesting techniques, together with approaches for reducing patient morbidity and accelerating donor site wound healing. The role of biologic agents, photobiomodulation therapy, local and systemic factors, and genes implicated in palatal wound healing are also discussed.

Progress in Research on TLR4-Mediated Inflammatory Response Mechanisms in Brain Injury after Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is one of the common clinical neurological emergencies. Its incidence accounts for about 5-9% of cerebral stroke patients. Even surviving patients often suffer from severe adverse prognoses such as hemiplegia, aphasia, cognitive dysfunction and even death. Inflammatory response plays an important role during early nerve injury in SAH. Toll-like receptors (TLRs), pattern recognition receptors, are important components of the body's innate immune system, and they are usually activated by damage-associated molecular pattern molecules. Studies have shown that with TLR 4 as an essential member of the TLRs family, the inflammatory transduction pathway mediated by it plays a vital role in brain injury after SAH. After SAH occurrence, large amounts of blood enter the subarachnoid space. This can produce massive damage-associated molecular pattern molecules that bind to TLR4, which activates inflammatory response and causes early brain injury, thus resulting in serious adverse prognoses. In this paper, the process in research on TLR4-mediated inflammatory response mechanism in brain injury after SAH was reviewed to provide a new thought for clinical treatment.

The role of dendritic cells in the immunomodulation to implanted biomaterials

Considering the substantial role played by dendritic cells (DCs) in the immune system to bridge innate and adaptive immunity, studies on DC-mediated immunity toward biomaterials principally center on their adjuvant effects in facilitating the adaptive immunity of codelivered antigens. However, the effect of the intrinsic properties of biomaterials on dendritic cells has not been clarified. Recently, researchers have begun to investigate and found that biomaterials that are nonadjuvant could also regulate the immune function of DCs and thus affect subsequent tissue regeneration. In the case of proteins adsorbed onto biomaterial surfaces, their intrinsic properties can direct their orientation and conformation, forming “biomaterial-associated molecular patterns (BAMPs)”. Thus, in this review, we focused on the intrinsic physiochemical properties of biomaterials in the absence of antigens that affect DC immune function and summarized the underlying signaling pathways. Moreover, we preliminarily clarified the specific composition of BAMPs and the interplay between some key molecules and DCs, such as heat shock proteins (HSPs) and high mobility group box 1 (HMGB1). This review provides a new direction for future biomaterial design, through which modulation of host immune responses is applicable to tissue engineering and immunotherapy.

Nonoxid-HMGB1 Attenuates Cognitive Impairment After Traumatic Brain Injury in Rats

Traumatic brain injury (TBI) is a major global burden of health. As an accepted inflammatory mediator, high mobility group box 1 (HMGB1) is found to be effective in facilitating neurogenesis and axonal regeneration. SH3RF2 (also known as POSHER), an E3 ligase SH3 domain-containing ring finger 2, belongs to the SH3RF family of proteins. Here, we aimed to investigate the role of redox states of HMGB1 on neurite outgrowth and regeneration both in vitro and in vivo. In this study, distinct recombinant HMGB1 redox isoforms were used. Sequencing for RNA-seq and data analysis were performed to find the potential downstream target of nonoxid-HMGB1 (3S-HMGB1). Protein changes and distribution of SH3RF2 were evaluated by western blot assays and immunofluorescence. Lentivirus and adeno-associated virus were used to regulate the expression of genes. Nonoxid-HMGB1-enriched exosomes were constructed and used to treat TBI rats. Neurological function was evaluated by OF test and NOR test. Results demonstrated that nonoxid-HMGB1 and fr-HMGB1, but not ds-HMGB1, promoted neurite outgrowth and axon elongation. RNA-seq and western blot assay indicated a significant increase of SH3RF2 in neurons after treated with nonoxid-HMGB1 or fr-HMGB1. Notably, the beneficial effects of nonoxid-HMGB1 were attenuated by downregulation of SH3RF2. Furthermore, nonoxid-HMGB1 ameliorated cognitive impairment in rats post-TBI via SH3RF2. Altogether, our experimental results suggest that one of the promoting neurite outgrowth and regeneration mechanisms of nonoxid-HMGB1 is mediated through the upregulated expression of SH3RF2. Nonoxid-HMGB1 is an attractive therapeutic candidate for the treatment of TBI.

Bioinspired Andrias davidianus-Derived wound dressings for localized drug-elution

Local drug delivery has received increasing attention in recent years. However, the therapeutic efficacy of local delivery of drugs is still limited under certain scenarios, such as in the oral cavity or in wound beds after resection of tumors. In this study, we introduce a bioinspired adhesive hydrogel derived from the skin secretions of Andrias davidianus (SSAD) as a wound dressing for localized drug elution. The hydrogel was loaded with aminoguanidine or doxorubicin, and its controlled drug release and healing-promoting properties were verified in a diabetic rat palatal mucosal defect model and a C57BL/6 mouse melanoma-bearing model, respectively. The results showed that SSAD hydrogels with different pore sizes could release drugs in a controllable manner and accelerate wound healing. Transcriptome analyses of the palatal mucosa suggested that SSAD could significantly upregulate pathways linked to cell adhesion and extracellular matrix deposition and had the ability to recruit keratinocyte stem cells to defect sites. Taken together, these findings indicate that property-controllable SSAD hydrogels could be a promising biofunctional wound dressing for local drug delivery and promotion of wound healing.

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The SSAD is a biologically drawable source with facile production, cost-effective, and safe.

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SSAD increases drug bioavailability with local application.

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The drug release rate can be controlled by regulating SSAD particle size.

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The SSAD-based wound dressing is adhesive.

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SSAD can also promote wound healing.

High Mobility Group Box 1 Protein in Osteoarthritic Knee Tissue and Chondrogenic Progenitor Cells: An Ex Vivo and In Vitro Study

OBJECTIVE

In osteoarthritis (OA), a loss of healthy cartilage extracellular matrix (ECM) results in cartilage degeneration. Attracting chondrogenic progenitor cells (CPCs) to injury sites and stimulating them toward chondrogenic expression profiles is a regenerative approach in OA therapy. High mobility group box 1 protein (HMGB1) is associated with chemoattractant and proinflammatory effects in various pathological processes. Here, we investigate the migratory effects of HMGB1 in knee OA and CPCs for the first time.

DESIGN

Immunohistochemistry, immunoblotting, and immunocytochemistry were performed to identify HMGB1 and its receptors, receptor for advanced glycation end products (RAGE) and toll-like receptor 4 (TLR4) in OA knee tissue, chondrocytes, and CPCs. In situ hybridization for HMGB1 mRNA was performed in CPCs ex vivo. The chemoattractant effects of HMGB1 on CPCs were analyzed in cell migration assays.

RESULTS

HMGB1 expression in OA tissue and OA chondrocytes was higher than in healthy specimens and cells. HMGB1, RAGE, and TLR4 were expressed in CPCs and chondrocytes. In situ hybridization revealed HMGB1 mRNA in CPCs after migration into OA knee tissue, and immunohistochemistry confirmed HMGB1 expression at the protein level. Stimulation via HMGB1 significantly increased the migration of CPCs.

CONCLUSIONS

Our results show the chemoattractant role of HMGB1 in knee OA. HMGB1 is released by chondrocytes and has migratory effects on CPCs. These effects might be mediated via RAGE and TLR4. The in vitro and ex vivo results of this study need to be confirmed in vivo.

Verbascoside Protects Gingival Cells against High Glucose-Induced Oxidative Stress via PKC/HMGB1/RAGE/NFκB Pathway

Impaired wound healing often occurs in patients with diabetes and causes great inconvenience to them. Aside from the presence of prolonged inflammation, the accumulation of oxidative stress is also implicated in the delayed wound healing. In the present study, we tested the effect of verbascoside, a caffeoyl phenylethanoid glycoside, on the improvement of cell viability and wound healing capacity of gingival epithelial cells under high glucose condition. We showed that verbascoside attenuated the high glucose-induced cytotoxicity and impaired healing, which may be associated with the downregulation of oxidative stress. Our results demonstrated that verbascoside increased the activity of the antioxidant enzyme SOD and reduced the oxidative stress indicator, 8-OHdG, as well as apoptosis. Moreover, verbascoside upregulated the PGC1-α and NRF1 expression and promoted mitochondrial biogenesis, which was mediated by suppression of PKC/HMGB1/RAGE/NFκB signaling. Likewise, we showed the inhibitory effect of verbascoside on oxidative stress was via repression of PKC/HMGB1/RAGE/NFκB activation. Also, our data suggested that the PKC-mediated oxidative stress may lead to the elevated production of inflammatory cytokines, IL-6 and IL-1β. Collectively, we demonstrated that verbascoside may be beneficial to ameliorate impaired oral wound healing for diabetic patients.

Malnutrition delayed wound healing after tooth extraction by HMGB1-related prolonged inflammation

Malnutrition causes prolonged inflammation, resulting in delayed wound healing. High mobility group box-1 (HMGB1) is a damage-associated molecular pattern that is present in the nuclei of macrophages and is secreted into the extracellular milieu in response to stimuli. It stimulates the production of interleukin-1β (IL-1β) through the receptors for advanced glycation end products (RAGE), inducing an inflammatory response, which is an essential response to initiate wound healing. We hypothesized that malnutrition may interfere with this cascade, causing abnormal inflammation and ultimately delaying wound healing. We used tooth-extracted mice with malnutrition fed with low-casein diet for two weeks. On days 3 and 7 after tooth extraction, the wound tissue was histologically observed and analyzed for several factors in the inflammation-regeneration lineage, including IL-1β, mesenchymal stem cells, myeloperoxidase activity, HMGB1, macrophage polarization, and adenosine 5-triphosphate (ATP). On day 7, delayed wound healing was observed with the following findings under malnutrition conditions: decreased mRNA expression of genes for regeneration and mesenchymal stem cell (MSC) accumulation, an obvious increase in myeloperoxidase and IL-1β mRNA expression, an increase in HMGB1 levels, and an increase in ATP concentration in tissues with elevated proportion of M2 macrophages. These results suggest that the significantly increased secretion of HMGB1 associated with the upregulated production of ATP and IL-1β secretion via the RAGE pathway may interfere with the resolution of inflammation and wound healing under the state of malnutrition.

Leucine-rich alpha-2 glycoprotein 1, high mobility group box 1, matrix metalloproteinase 3 and annexin A1 as biomarkers of ulcerative colitis endoscopic and histological activity

OBJECTIVE

The LRG, HMGB1, MMP3 and ANXA1 proteins have been implicated in different inflammatory pathways in ulcerative colitis (UC), but their role as specific biomarkers of both endoscopic and histological activity has yet to be elucidated. In the present study, we aimed to evaluate the LRG1, HMGB1, MMP3 and ANXA1 as potential serum biomarkers for UC endoscopic and histological activity.

METHODS

This cross-sectional study included UC patients under 5-ASA, and healthy controls (HC) undergoing colonoscopy. Blood and biopsy samples were obtained and endoscopic Mayo sub-score (Ms) was recorded for the UC patients. Intramucosal calprotectin as a marker of histologic activity was evaluated in all biopsy samples and serum LRG1, HMGB1, MMP3 and ANXA1 levels were measured in the blood samples.

RESULTS

The HCs ANXA1 level was lower compared to that of the UC group [P = 0.00, area under the curve (AUC) = 0.881] and so was the HCs MMP3 level compared to that of patients (P = 0.00, AUC = 0.835). The HCs ANXA1 levels were also lower compared to these of the independent Ms groups, even to the Ms = 0 (P = 0.00, AUC = 0.913). UC endoscopic activity was associated with MMP3 levels (r = 0.54, P = 0.000) but not with ANXA1, LRG1 and HMGB1 levels CONCLUSION: Serum ANXA1 is a potential diagnostic biomarker of UC and serum MMP3 is a potential biomarker of UC endoscopic and histological activity.

High Mobility Group Box 1 Expression in Oral Inflammation and Regeneration

High mobility group box 1 (HMGB1) is a non-histone DNA-binding protein of about 30 kDa. It is released from a variety of cells into the extracellular milieu in response to inflammatory stimuli and acts on specific cell-surface receptors, such as receptors for advanced glycation end-products (RAGE), Toll-like receptor (TLR)2, TLR4, with or without forming a complex with other molecules. HMGB1 mediates various mechanisms such as inflammation, cell migration, proliferation, and differentiation. On the other hand, HMGB1 enhances chemotaxis acting through the C-X-C motif chemokine ligand (CXCL)12/C-X-C chemokine receptor (CXCR)4 axis and is involved in regeneration. In the oral cavity, high levels of HMGB1 have been detected in the gingival tissue from periodontitis and peri-implantitis patients, and it has been shown that secreted HMGB1 induces pro-inflammatory cytokine expression, such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, which prolong inflammation. In contrast, wound healing after tooth extraction or titanium dental implant osseointegration requires an initial acute inflammation, which is regulated by secreted HMGB1. This indicates that secreted HMGB1 regulates angiogenesis and bone remodeling by osteoclast and osteoblast activation and promotes bone healing in oral tissue repair. Therefore, HMGB1 can prolong inflammation in the periodontal tissue and, conversely, can regenerate or repair damaged tissues in the oral cavity. In this review, we highlight the role of HMGB1 in the oral cavity by comparing its function and regulation with its function in other diseases. We also discuss the necessity for further studies in this field to provide more specific scientific evidence for dentistry.

Two Different Missense C1S Mutations, Associated to Periodontal Ehlers-Danlos Syndrome, Lead to Identical Molecular Outcomes

Ehlers-Danlos syndromes (EDS) are clinically and genetically heterogeneous disorders characterized by soft connective tissue alteration like joint hypermobility and skin hyper-extensibility. We previously identified heterozygous missense mutations in the C1R and C1S genes, coding for the complement C1 proteases, in patients affected by periodontal EDS, a specific EDS subtype hallmarked by early severe periodontitis leading to premature loss of teeth and connective tissue alterations. Up to now, there is no clear molecular link relating the nominal role of the C1r and C1s proteases, which is to activate the classical complement pathway, to these heterogeneous symptoms of periodontal EDS syndrome. We aim therefore to elucidate the functional effect of these mutations, at the molecular and enzymatic levels. To explore the molecular consequences, a set of cell transfection experiments, recombinant protein purification, mass spectroscopy and N-terminal analyses have been performed. Focusing on the results obtained on two different C1S variants, namely p.Val316del and p.Cys294Arg, we show that HEK293-F cells stably transfected with the corresponding C1s variant plasmids, unexpectedly, do not secrete the full-length mutated C1s, but only a truncated Fg40 fragment of 40 kDa, produced at very low levels. Detailed analyses of the Fg40 fragments purified for the two C1s variants show that they are identical, which was also unexpected. This suggests that local misfolding of the CCP1 module containing the patient mutation exposes a novel cleavage site, between Lys353 and Cys354, which is not normally accessible. The mutation-induced Fg40 fragment contains the intact C-terminal serine protease domain but not the N-terminal domain mediating C1s interaction with the other C1 subunits, C1r, and C1q. Thus, Fg40 enzymatic activity escapes the normal physiological control of C1s activity within C1, potentially providing a loss-of-control. Comparative enzymatic analyses show that Fg40 retains the native esterolytic activity of C1s, as well as its cleavage efficiency toward the ancillary alarmin HMGB1 substrate, for example, whereas the nominal complement C4 activation cleavage is impaired. These new results open the way to further molecular explorations possibly involving subsidiary C1s targets.

HGMB1 and RAGE as Essential Components of Ti Osseointegration Process in Mice

The release of the prototypic DAMP High Mobility Group Box 1 (HMGB1) into extracellular environment and its binding to the Receptor for Advanced Glycation End Products (RAGE) has been described to trigger sterile inflammation and regulate healing outcome. However, their role on host response to Ti-based biomaterials and in the subsequent osseointegration remains unexplored. In this study, HMGB1 and RAGE inhibition in the Ti-mediated osseointegration were investigated in C57Bl/6 mice. C57Bl/6 mice received a Ti-device implantation (Ti-screw in the edentulous alveolar crest and a Ti-disc in the subcutaneous tissue) and were evaluated by microscopic (microCT [bone] and histology [bone and subcutaneous]) and molecular methods (ELISA, PCR array) during 3, 7, 14, and 21 days. Mice were divided into 4 groups: Control (no treatment); GZA (IP injection of Glycyrrhizic Acid for HMGB1 inhibition, 4 mg/Kg/day); RAP (IP injection of RAGE Antagonistic Peptide, 4 mg/Kg/day), and vehicle controls (1.5% DMSO solution for GZA and 0.9% saline solution for RAP); treatments were given at all experimental time points, starting 1 day before surgeries. HMGB1 was detected in the Ti-implantation sites, adsorbed to the screws/discs. In Control and vehicle groups, osseointegration was characterized by a slight inflammatory response at early time points, followed by a gradual bone apposition and matrix maturation at late time points. The inhibition of HMGB1 or RAGE impaired the osseointegration, affecting the dynamics of mineralized and organic bone matrix, and resulting in a foreign body reaction, with persistence of macrophages, necrotic bone, and foreign body giant cells until later time points. While Control samples were characterized by a balance between M1 and M2-type response in bone and subcutaneous sites of implantation, and also MSC markers, the inhibition of HMGB1 or RAGE caused a higher expression M1 markers and pro-inflammatory cytokines, as well chemokines and receptors for macrophage migration until later time points. In conclusion, HMGB1 and RAGE have a marked role in the osseointegration, evidenced by their influence on host inflammatory immune response, which includes macrophages migration and M1/M2 response, MSC markers expression, which collectively modulate bone matrix deposition and osseointegration outcome.

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.