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Introduction Oxidative stress, an imbalance between reactive oxygen species (ROS) production and antioxidant defenses, plays an important role in various dental diseases. Local anesthetics are frequently used in dentistry. The potential antioxidant activity of dental local anesthetics can contribute to dental practice. Therefore, this study aimed to investigate the ROS-scavenging activities of three commonly used dental local anesthetics, lidocaine, prilocaine, and articaine, focusing on their effects on hydroxyl radicals (HOâ¢) and superoxide anions (O2 â¢-). Materials and methods The electron spin resonance (ESR) spin-trapping technique was employed to specifically measure the ROS-scavenging activities of these local anesthetics at varying concentrations. Results Lidocaine, prilocaine, and articaine exhibited concentration-dependent HOâ¢-scavenging activities, with IC50 values of 0.029%, 0.019%, and 0.014%, respectively. Lidocaine and prilocaine showed concentration-dependent O2 â¢--scavenging activity, with IC50 values of 0.033% and 0.057%, respectively. However, articaine did not scavenge O2 â¢-. Conclusions The proactive use of dental local anesthetics may mitigate oxidative injury and inflammatory damage through direct ROS scavenging. However, further research is needed to elucidate the specific mechanisms underlying the antioxidant effects of these dental local anesthetics and their potential impact on the dental diseases associated with oxidative stress.
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BACKGROUND: Photodynamic therapy (PDT) is a cancer-targeted treatment that uses a photosensitizer (PS) and irradiation of a specific wavelength to exert cytotoxic effects. To enhance the antitumor effect against head and neck squamous cell carcinoma (HNSCC), we developed a new phototherapy, intelligent targeted antibody phototherapy (iTAP). This treatment uses a combination of immunotoxin (IT) and a PS for PDT and light irradiation. In our prior study, we demonstrated that an immunotoxin (IT) consisting of an anti-ROBO1 antibody conjugated to saporin, when used in combination with the photosensitizer (PS) disulfonated aluminum phthalocyanine (AlPcS2a) and irradiated with light at the appropriate wavelength, resulted in increased cytotoxicity against head and neck squamous cell carcinoma (HNSCC) cells. ROBO1 is a receptor known to be involved in the progression of cancer. In this study, we newly investigate the iTAP targeting epidermal growth factor receptor (EGFR) which is widely used as a therapeutic target for HNSCC. METHODS: We checked the expression of EGFR in HNSCC cell lines, SAS, HO-1-u-1, Sa3, and HSQ-89. We analyzed the cytotoxicity of saporin-conjugated anti-EGFR antibody (cetuximab) (IT-Cmab), mono-L-aspartyl chlorin e6 (NPe6, talaporfin sodium), and light (664 nm) irradiation (i.e., iTAP) in SAS, HO-1-u-1, Sa3, and HSQ-89 cells. RESULTS: EGFR was expressed highly in Sa3, moderately in HO-1-u-1, SAS, and nearly not in HSQ-89. Cmab alone or IT-Cmab alone did not show cytotoxic effects in Sa3, HO-1-u-1, and HSQ-89 cells, which have moderate or low expression levels of EGFR protein. However, the iTAP method enhanced the cytotoxicity of IT-Cmab by the photodynamic effect in Sa3 and HO-1-u-1 cells, which have moderate levels of EGFR expression. CONCLUSION: Our study is the first to report on the iTAP method using IT-Cmab and NPe6 for HNSCC. The cytotoxic effects are enhanced in cell lines with moderate levels of EGFR protein expression, but not in nonexpressing cell lines, which is expected to expand the range of therapeutic windows and potentially reduce complications.
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OBJECTIVES: Lactoferrin (LF) possesses diverse biological functions. We previously reported that bovine LF (bLF) attenuates lipopolysaccharide-induced bone resorption in osteoblasts. In addition to its ability to inhibit osteoclastogenesis, bLF has been implicated in stimulating bone formation. However, the molecular mechanisms of bLF in bone cell anabolism remain unclear. Here, we tried to analyse the molecular mechanisms involved in osteogenesis in the presence of bLF. METHODS: Alkaline phosphatase activity, Runx2 activity, gene expression, and Alizarin red staining were analyzed to evaluate the osteogenic differentiation status. The expression of the Smads and mitogen-activated protein kinase (MAPK) signaling molecules was analyzed via western blotting. Ex vivo organ cultures of mouse calvariae were performed to evaluate the effect of bLF on bone regeneration. RESULTS: bLF enhanced the osteoblastic differentiation of mesenchymal stem cells through activation of Smad2/3 and p38 MAPK, which increased the transcriptional activity of Runx2. bLF treatment also enhanced osteoblastic differentiation and mineralized nodule formation of osteoblast-lineage cells, and repaired bone defects ex vivo. Moreover, inhibition of Smad2/3 or p38 MAPK signaling reduced the anabolic effects of bLF. Together, these results suggested that bLF is a potent osteogenic factor, which mediates its function via activation of the Smad2/3 and p38 MAPK signaling pathways. CONCLUSIONS: Here, we described a novel function of bLF and its signal transduction mechanisms in osseous tissue. Along with inhibiting osteoclastogenesis, bLF may limit further osteoclast formation and contribute to bone mass enlargement. Thus, bLF represents a potentially valuable therapeutic agent for bone regeneration and destructive bone diseases.
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Lactoferrina , Osteogênese , Animais , Diferenciação Celular , Camundongos , Osteoblastos , Osteoclastos , Proteína Smad2 , Proteína Smad3 , Proteínas Quinases p38 Ativadas por MitógenoRESUMO
The maturation of chondrocytes is strictly regulated for proper endochondral bone formation. Although recent studies have revealed that intracellular metabolic processes regulate the proliferation and differentiation of cells, little is known about how changes in metabolite levels regulate chondrocyte maturation. To identify the metabolites which regulate chondrocyte maturation, we performed a metabolome analysis on chondrocytes of Sik3 knockout mice, in which chondrocyte maturation is delayed. Among the metabolites, acetyl-CoA was decreased in this model. Immunohistochemical analysis of the Sik3 knockout chondrocytes indicated that the expression levels of phospho-pyruvate dehydrogenase (phospho-Pdh), an inactivated form of Pdh, which is an enzyme that converts pyruvate to acetyl-CoA, and of Pdh kinase 4 (Pdk4), which phosphorylates Pdh, were increased. Inhibition of Pdh by treatment with CPI613 delayed chondrocyte maturation in metatarsal primordial cartilage in organ culture. These results collectively suggest that decreasing the acetyl-CoA level is a cause and not result of the delayed chondrocyte maturation. Sik3 appears to increase the acetyl-CoA level by decreasing the expression level of Pdk4. Blocking ATP synthesis in the TCA cycle by treatment with rotenone also delayed chondrocyte maturation in metatarsal primordial cartilage in organ culture, suggesting the possibility that depriving acetyl-CoA as a substrate for the TCA cycle is responsible for the delayed maturation. Our finding of acetyl-CoA as a regulator of chondrocyte maturation could contribute to understanding the regulatory mechanisms controlling endochondral bone formation by metabolites.
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Acetilcoenzima A/metabolismo , Condrócitos/metabolismo , Osteogênese , Proteínas Serina-Treonina Quinases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Condrócitos/citologia , Condrogênese , Feminino , Deleção de Genes , Metaboloma , Camundongos , Camundongos Knockout , Proteínas Serina-Treonina Quinases/genéticaRESUMO
IMPACT STATEMENT: Cartilage particles derived from human induced pluripotent stem cells (hiPS-Carts) are one candidate source for transplants for treatment of articular cartilage damage. This study shows that hiPS-Carts integrate with each other in an in vitro model and analyzed the course of the integration. The integration starts at the perichondrium-like membrane at around 1 week and then progresses to the central cartilage within 4-8 weeks. The results indicate that FGF18 secreted from the perichondrium-like membrane accelerates the initial step of integration. The findings contribute to understanding how hiPS-Carts form repair tissue and provide clue to accelerate healing after transplantation.
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Cartilagem Articular/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Contagem de Células , Linhagem Celular , Fatores de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica , Humanos , Membranas , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
Osteoarthritis is a common debilitating joint disorder. Risk factors for osteoarthritis include age, which is associated with thinning of articular cartilage. Here we generate chondrocyte-specific salt-inducible kinase 3 (Sik3) conditional knockout mice that are resistant to osteoarthritis with thickened articular cartilage owing to a larger chondrocyte population. We also identify an edible Pteridium aquilinum compound, pterosin B, as a Sik3 pathway inhibitor. We show that either Sik3 deletion or intraarticular injection of mice with pterosin B inhibits chondrocyte hypertrophy and protects cartilage from osteoarthritis. Collectively, our results suggest Sik3 regulates the homeostasis of articular cartilage and is a target for the treatment of osteoarthritis, with pterosin B as a candidate therapeutic.