Osteoarthritis (OA) is a type of prevalent degenerative joint disease featured by cartilage breakdown, inflammation, as well as pain, leading to significant disability. Inflammation, mediated by cytokines such as IL-1β, plays a central role in OA pathogenesis. Cirsilineol (CSL), a bioactive flavonoid, has shown anti-inflammatory and antioxidant properties in various models, however, its effects on OA remains unclear. This research was to investigate the effects of cirsilineol on IL-1β-stimulated apoptosis as well as inflammatory response in human osteoarthritic chondrocytes. Herein, we revealed that CSL improves cell viability in human osteoarthritic chondrocytes. Furthermore, CSL was shown to effectively suppress the IL-1β-stimulated inflammatory response. Additionally, CSL inhibited the IL-1β-stimulated remodeling of ECM. Notably, the protective effects of CSL were associated with the suppression of the NF-κB pathway. In conclusion, CSL inhibits IL-1β-stimulated apoptosis and inflammatory response in human osteoarthritic chondrocytes via mediating NF-κB pathway, and could therefore serve as a drug of OA.

We aimed to investigate whether curcumin can employ the phosphatidylinositol 3-hydroxy kinase (PI3K)/protein kinase B (Akt) signaling pathway to relieve inflammation in human dental pulp cells (hDPCs) mediated by lipopolysaccharide (LPS). The surface markers of hDPCs were detected by immunofluorescence assay. The toxicity of curcumin and LPS on hDPCs was determined using the methyl thiazolyl tetrazolium assay. The cells were treated with LPS and randomized to Control group (cultured with DMEM), LPS group (culture with 1 μg/ml LPS-containing medium), Cru-L group (incubation with medium containing 1 μg/ml LPS and 5 μmol/l curcumin), Cru-M group (incubation with medium containing 1 μg/ml LPS and 10 μmol/l curcumin), Cru-H group (incubation with medium containing 1 μg/ml LPS and 30 μmol/l curcumin), and Cru-H+SC79 group (incubation with medium containing 1 μg/ml LPS, 30 μmol/l curcumin and SC79 10 μmol/l). The cell counting kit-8 assay for hDPC survival rate and flow cytometry for hDPC apoptosis rate were implemented. The Cru-L group, Cru-M group and Cru-H group, in comparison to the LPS group, had a significantly raised cell survival rate, along with significant decreases in the phosphorylated protein kinase B (p-Akt)/Akt ratio, apoptosis rate, IL-6, IL-1β and TNF-α levels, and p-PI3K/PI3K ratio (P<0.05). In comparison with the Cru-H group, the Cru-H+SC79 group had a significantly decreased cell survival rate, and significantly increased p-PI3K/PI3K ratio, apoptosis rate, p-Akt/Akt ratio, and IL-6, IL-1β and TNF-α levels (P<0.05). Curcumin can suppress the PI3K/Akt signaling pathway to mitigate LPS-induced inflammation of hDPCs, thus relieving the inflammatory injury of dental pulp tissues.

Temporomandibular joint osteoarthritis (TMJ-OA) is a widespread joint pathology and has a heightened risk of occurring in patients with anterior disc displacement (ADD), suggesting a potential link between disc displacement and TMJ-OA. However, how ADD causes condylar cartilage deformity without excessive loading on the condyle remains unclear. Therefore, in this study, we aimed to investigate the effects of ADD on temporomandibular joint (TMJ) in rats. Twelve-week-old male Wistar rats were randomly assigned to three groups: ADD, sham surgery, and control. A 4-0 silk thread was used to ligate the anterior part of the articular capsule to the posterior part of the zygomatic arch, securing the articular disc 3 mm forward. The ADD and sham groups were sacrificed 4, 6, and 8 weeks after surgery to perform radiological analysis on the TMJ using micro-computed tomography (micro-CT) and histological analyses. CT images of both coronal and sagittal sections revealed bone deformities in the condyles of the ADD group. The obtained images closely resembled the damaged surface of condyles observed in a clinical case of TMJ-OA. Histologically, anterior disc displacement was observed in the ADD group, along with an increase in thickness of the cartilage layer and a reduction in the cartilage matrix within the hypertrophic layer. The expressions of matrix metalloproteinase-13 and alkaline phosphatase were significantly upregulated in the hypertrophic layer and subchondral bone beneath the cartilage layer, indicating that ADD activated cartilage and bone remodeling. This study reported morphological changes of mandibular condyle and histological changes throughout the TMJ and showed that ADD without excessive loading could cause TMJ-OA

This study evaluated the aging phenomenon and cell affinity of titanium after storage in ozone nanobubble water (NBW3). JIS Class 2 pure titanium disks were mirror polished, treated with glow discharge under an argon atmosphere, and stored under four different storage conditions: atmosphere, distilled water, acetone, and NBW3. X-ray photoelectron spectroscopy (XPS) was used to measure the changes in the adhesion and contact angles of the hydrocarbon compounds. Human mesenchymal stem cells were seeded on titanium disks and stored for 24 h under the four different conditions. The number of adherent cells was measured, and their morphology was observed using scanning electron microscopy and confocal laser scanning microscopy. Alkaline phosphatase (ALP) staining was performed after 7 days of cell culture. XPS analysis revealed that samples stored in atmosphere exhibited a high C1s peak, indicative of the attachment of hydrocarbon compounds; however, the peak in NBW3 remained low. Titanium disks stored in NBW3 exhibited higher wettability, higher cell attachment counts and cell adhesion, and increased ALP activity compared to those stored in atmosphere. Storage of titanium disks in NBW3 may prove effective in inhibiting the aging process of the titanium surfaces and maintaining high wettability and cell affinity.

Liquid-liquid phase separation (LLPS) has emerged as a significant mechanism for cellular organization, impacting various biological processes, including Wnt/β-catenin signaling. This study investigates the role of LLPS in the regulation of β-catenin in HEK293 cells, particularly in response to Wnt3a signaling. Our findings demonstrate that β-catenin is regulated by LLPS, forming spherical droplets indicative of this phenomenon. Fluorescence recovery after photobleaching (FRAP) assays revealed that these droplets exhibit reversible dynamics, further confirming their phase-separated nature. Importantly, treatment with Wnt3a led to an increase in β-catenin levels, while simultaneously reducing the recovery of fluorescence intensity in FRAP experiments, suggesting that enhanced Wnt signaling may stimulate the release of β-catenin from LLPS. Immunoprecipitation studies indicated that β-catenin binds to glycogen synthase kinase 3β (Gsk-3β) within the LLPS state, highlighting a potential regulatory mechanism whereby LLPS facilitates the phosphorylation and subsequent degradation of β-catenin. The addition of 1,6-hexanediol disrupted the β-catenin/Gsk-3β interaction, reinforcing the idea that LLPS plays a critical role in modulating these biochemical interactions. The findings presented in this study suggest that LLPS is not only crucial for the spatial organization of β-catenin but also serves as a regulatory mechanism for its signaling functions in the Wnt pathway. Given the association of aberrant Wnt signaling with various diseases, including cancer and neurodegenerative disorders, understanding the role of LLPS in this context may provide new insights into therapeutic strategies targeting these pathological conditions.

To evaluate new image processing methods using deep learning and to obtain basic data for improving the quality of oral mucosa images, we processed lingual mucosa images (dorsum of tongue, lateral border of tongue, and sublingual surface) obtained our previously developed observation device (oral mucoscope) using three types of Generative Adversarial Network (GAN), TecoGAN, Real-ESRGAN, and Real-CUGAN network. The images were evaluated objectively by calculated values, and sensory evaluation by dental clinicians. The TecoGAN-processed image had slight contour correction and appeared to be the most natural image. The Real-ESRGAN processed image was intermediate in quality, between that of TecoGAN and Real-CUGAN, and showed outline details of the lingual papillae. Real-CUGAN improved image graininess after processing but appeared to have poor morphological reproducibility of contour details. The objective evaluation value, LPIPS, showed a significant decrease in value in the order of TecoGAN, Real-ESRGAN, and Real-CUGAN, and a similar trend to the subjective evaluation value (MOS) by dentists, but in PSNR and SSIM, no significant differences were observed between the TecoGAN, Real-ESRGAN, and Real-CUGAN in PSNR and SSIM. In a comparison by observation aspect, the lingual dorsum was lower than the other observation aspects in terms of objective rating values, but there was no significant difference between the three observation surfaces in terms of subjective assessment values by dentists. The site of the mucosa may be affected by a deep “feature” extracted from the image. Further study is needed to evaluate images after super-resolution processing when considering the morphological characteristics of the mucosal surface.