Study on the mechanism of naringin in promoting bone differentiation: In vitro and in vivo study.

Objective: Osteoporosis is a common clinical bone disease that occurs most frequently in middle-aged and elderly people. Various traditional herbal medicine formulations have shown significant benefits in models of osteoporosis. In this study, we aim to investigate the osteogenic efficacy of naringin (NRG) in the osteoporotic state. Design: We treated Bone marrow stromal cells (BMSCs) with various concentrations of NRG for 3 and 7 days. BMSC proliferation was measured by the MTT assay. The effect of NRG on the osteogenic differentiation of BMSCs was detected by ALP and alizarin red staining. The effect of NRG on the BMP2/Runx2/Osterix signaling pathway was analyzed by using real-time PCR. The effect of NRG on the oestrogen receptor was measured by Enzyme-linked immunosorbent assay. In vivo animal experiments were performed by micro-computed tomography and ALP immunohistochemistry to determine the ectopic osteogenic effect of NRG sustained-release nanoparticles in a mouse model of osteoporosis. Results: NRG promoted the proliferation and osteogenic differentiation of BMSCs. Moreover, it also activated the BMP2/Runx2/Osterix signaling pathway. When NRG sustained-release nanoparticles were added in vivo in animal experiments, we found that NRG sustained-release nanoparticles had better ectopic osteogenic effects in a mouse model of osteoporosis. Conclusions: NRG induced osteoblastic differentiation of BMSCs by activating the BMP2/Runx2/Osterix signaling pathway and promoted the regulation of oestrogen receptor pathway protein expression, and NRG sustained-release nanoparticles exerted a more significant in vivo ectopic osteogenic effect in an osteoporosis mouse model. Therefore, naringin is expected to be developed as a novel treatment for inducing osteogenesis, because of its ubiquitous, cost-efficient, and biologically active characteristics. However, further research is needed on how to improve the pharmacokinetic properties of naringin and its specific mechanism.

Erratum: Functionalization of SF/HAP Scaffold with GO-PEI-miRNA inhibitor Complexes to Enhance Bone Regeneration through Activating Transcription Factor 4: Erratum.

[This corrects the article DOI: 10.7150/thno.34676.].

Lycium barbarum polysaccharide modulates gut microbiota to alleviate rheumatoid arthritis in a rat model.

Rheumatoid arthritis (RA) seriously impairs the quality of life of sufferers. It has been shown that Lycium barbarum polysaccharide (LBP), a natural active indigestible ingredient with medicinal and edible functions, can effectively relieve RA, however, whether this effect is related to gut microbiota is not known. This study aimed to explore the RA alleviating mechanism of LBP mediated by gut microbiota using a collagen-induced arthritis rat model. The results showed that LBP significantly changed the gut microflora structure accompanied with the RA alleviation. Specifically, a LBP intervention reduced the relative abundance of Lachnospiraceae_NK4A136_group and uncultured_bacterium_f_Ruminococcaceae and significantly increased the abundance of Romboutsia, Lactobacillus, Dubosiella and Faecalibaculum. The mRNA contents of several colonic epithelial genes including Dpep3, Gstm6, Slc27a2, Col11a2, Sycp2, SNORA22, Tnni1, Gpnmb, Mypn and Acsl6, which are potentially associated to RA, were down-regulated due to the DNA hypermethylation, possibly caused by the elevating content of a bacterial metabolite S-adenosyl methionine (SAM). In conclusion, our current study suggests that LBP alleviated RA by reshaping the composition of intestinal microflora which may generate SAM, inducing DNA hypermethylation of RA-related genes in the host intestinal epithelium and subsequently reducing their expression.

Osteogenic peptides in periodontal ligament stem cell-containing three-dimensional bioscaffolds promote bone healing.

Bone tissue engineering shows great potential in bone regeneration; however, the lack of bone growth factors with high biocompatibility and efficiency is a major concern. Oligopeptides have drawn great attention due to their high biological efficacy, low toxicity, and low molecular weight. The oligopeptide SDSSD promotes the osteogenesis of human periodontal ligament stem cells (hPDLSCs) in vitro. The SDSSD-modified three-dimensional (3D) bioscaffolds promote osteogenesis and bone formation in the subcutaneous pockets of BALB/c nude mice and facilitate bone healing in vivo. Mechanistically, SDSSD promoted bone formation by binding to G protein-coupled receptors and regulating the AKT signaling pathway. 3D-printing bioscaffolds with SDSSD may be potential bone tissue engineering materials for treating bone defects.

A N6-methyladenosine-related long noncoding RNAs model for predicting prognosis in oral squamous cell carcinoma: Association with immune cell infiltration and tumor metastasis.

OBJECTIVES: We aim to investigate the prognostic value of potential prognostic m6A-related lncRNAs in oral squamous cell carcinoma (OSCC) samples and construct a m6A-related lncRNAs prognostic model of OSCC survival outcomes, find new clues for OSCC prognosis improvement. MATERIALS AND METHODS: Data of m6A-related lncRNAs were obtained from OSCC samples in TCGA database. Prognostic m6A-related lncRNAs were selected by univariate Cox regression analysis. M6A-related lncRNAs prognostic signature was analyzed by least absolute shrinkage and selection operator (LASSO) regression. RESULTS: 271 m6A-related lncRNAs were identified in OSCC lncRNAs, 16 of which were highly correlated with OSCC survival outcomes. Two clusters were created based on 16 prognostic valuable m6A-related lncRNAs. Characteristics of tumor immune and metastasis were identified in cluster 2 and the overall survival (OS) was worse of cluster 2 than that of cluster 1. Eleven m6A-related lncRNAs were selected from prognostic lncRNAs to establish a risk prediction signature via LASSO regression. Results showed that the OS of 1 year was lower in the high-risk group than low-risk group. The area under the curve in the training cohort was 0.704 at 1 year and 0.880 at 5 years. Multivariate Cox regression results suggested that the risk score calculated based on the m6A-related lncRNAs differential expressions was an independent predictor of OS in both two cohorts. CONCLUSION: We identified prognostic valuable m6A-related lncRNAs and demonstrated a reliable m6A-related lncRNA prognostic model for OSCC patients.

A functional motif of long noncoding RNA Nron against osteoporosis.

Long noncoding RNAs are widely implicated in diverse disease processes. Nonetheless, their regulatory roles in bone resorption are undefined. Here, we identify lncRNA Nron as a critical suppressor of bone resorption. We demonstrate that osteoclastic Nron knockout mice exhibit an osteopenia phenotype with elevated bone resorption activity. Conversely, osteoclastic Nron transgenic mice exhibit lower bone resorption and higher bone mass. Furthermore, the pharmacological overexpression of Nron inhibits bone resorption, while caused apparent side effects in mice. To minimize the side effects, we further identify a functional motif of Nron. The delivery of Nron functional motif to osteoclasts effectively reverses bone loss without obvious side effects. Mechanistically, the functional motif of Nron interacts with E3 ubiquitin ligase CUL4B to regulate ERα stability. These results indicate that Nron is a key bone resorption suppressor, and the lncRNA functional motif could potentially be utilized to treat diseases with less risk of side effects.

Oral squamous cell carcinoma (OSCC)-derived exosomal MiR-221 targets and regulates phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) to promote human umbilical vein endothelial cells migration and tube formation.

Oral squamous cell carcinoma (OSCC) is the most common tumor of the oral cavity. Studies have shown that exosomal miRNAs from cancer cells play an important role in mediating the cellular environment. The objective was to investigate the effect of OSCC-derived exosomes microRNA-221 (miR-221) in OSCC. We used quantitative real-time PCR (qRT-PCR) and western blotting to determine PIK3R1 and miR-221 expressions in OSCC tissue or peripheral blood serum. Exosomes of OSCC cell line CAL27 were extracted and characterized. Exosomal miR-221 expression was detected by qRT-PCR. Dual-luciferase was performed to validate the targeted regulatory relationship of miR-221 on PIK3R1. Transwell and tube formation assay were applied to detect the effect of OSCC-derived exosomal miR-221 on HUVEC migration and angiogenesis. qRT-PCR confirmed that PIK3R1 expression was downregulated in OSCC tissue and cell line, while miR-221 expression was upregulated. miR-221 expression in OSCC cell line-derived exosome elevated. miR-221 could target and negatively regulate PIK3R1 expression. In addition, OSCC-derived miR-221 could promote HUVEC migration and angiogenesis. In conclusion, OSCC-derived exosomal miR-221 could target and negatively regulate PIK3R1 expression, as well as promote vascular endothelial cell migration and angiogenesis.

miR-146a-5p targets Sirt1 to regulate bone mass.

MicroRNAs (miRNAs) have been proven to serve as key post-transcriptional regulators, affecting diverse biological processes including osteogenic differentiation and bone formation. Recently, it has been reported that miR-146a-5p affects the activity of both osteoblasts and osteoclasts. However, the target genes of miR-146a-5p in these procedures remain unknown. Here we identify miR-146a-5p as a critical suppressor of osteoblastogenesis and bone formation. We found that miR-146a-5p knockout mice exhibit elevated bone formation and enhanced bone mass in vivo. Consistently, we also found that miR-146a-5p inhibited the osteoblast differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Importantly, we further demonstrated that miR-146a-5p directly targeted Sirt1 to inhibit osteoblast activity. Additionally, we showed that the expression of miR-146a-5p gradually increased in femurs with age not only in female mice but also in female patients, and miR-146a-5p deletion protected female mice from age-induced bone loss. These data suggested that miR-146a-5p has a crucial role in suppressing the bone formation and that inhibition of miR-146a-5p may be a strategy for ameliorating osteoporosis.

Nanomaterials and hepatic disease: toxicokinetics, disease types, intrinsic mechanisms, liver susceptibility, and influencing factors.

The widespread use of nanomaterials (NMs) has raised concerns that exposure to them may introduce potential risks to the human body and environment. The liver is the main target organ for NMs. Hepatotoxic effects caused by NMs have been observed in recent studies but have not been linked to liver disease, and the intrinsic mechanisms are poorly elucidated. Additionally, NMs exhibit varied toxicokinetics and induce enhanced toxic effects in susceptible livers; however, thus far, this issue has not been thoroughly reviewed. This review provides an overview of the toxicokinetics of NMs. We highlight the possibility that NMs induce hepatic diseases, including nonalcoholic steatohepatitis (NASH), fibrosis, liver cancer, and metabolic disorders, and explore the underlying intrinsic mechanisms. Additionally, NM toxicokinetics and the potential induced risks in the livers of susceptible individuals, including subjects with liver disease, obese individuals, aging individuals and individuals of both sexes, are summarized. To understand how NM type affect their toxicity, the influences of the physicochemical and morphological (PCM) properties of NMs on their toxicokinetics and toxicity are also explored. This review provides guidance for further toxicological studies on NMs and will be important for the further development of NMs for applications in various fields.

Effects of DLX3 on the osteogenic differentiation of induced pluripotent stem cell­derived mesenchymal stem cells.

Osteoporosis is a disease characterized by the degeneration of bone structure and decreased bone mass. Induced pluripotent stem cell­derived mesenchymal stem cells (iPSC­MSCs) have multiple advantages that make them ideal seed cells for bone regeneration, including high­level proliferation, multi­differentiation potential and favorable immune compatibility. Distal­less homeobox (DLX)3, an important member of the DLX family, serves a crucial role in osteogenic differentiation and bone formation. The present study aimed to evaluate the effects of DLX3 on the proliferation and osteogenic differentiation of human iPSC­MSCs. iPSC­MSCs were induced from iPSCs, and identified via flow cytometry. Alkaline phosphatase (ALP), Von Kossa, Oil Red O and Alcian blue staining methods were used to evaluate the osteogenic, adipogenic and chondrogenic differentiation of iPSC­MSCs. DLX3 overexpression plasmids were constructed and transfected into iPSC­MSCs to generate iPSC­MSC­DLX3. iPSC­MSC­GFP was used as the control. Reverse transcription­quantitative PCR (RT­qPCR) and western blotting were performed to measure the expression of DLX3 2 days after transfection. Subsequently, cell proliferation was assessed using a Cell Counting Kit­8 assay on days 1, 3, 5 and 7. RT­qPCR and western blotting were used to analyze osteogenic­related gene and protein expression levels on day 7. ALP activity and mineralized nodules were assessed via ALP staining on day 14. Statistical analysis was performed using an unpaired Student's t­test. Flow cytometry results demonstrated that iPSC­MSCs were positive for CD73, CD90 and CD105, but negative for CD34 and CD45. iPSC­MSC­DLX3 had significantly lower proliferation compared with iPSC­MSC­GFP on days 5 and 7 (P<0.05). mRNA expression levels of osteogenic markers, such as ALP, osteopenia (OPN), osteocalcin (OCN) and Collagen Type I (COL­1), were significantly increased in iPSC­MSC­DLX3 compared with iPSC­MSC­GFP on day 7 (P<0.05). Similarly, the protein expression levels of ALP, OCN, OPN and COL­1 were significantly increased in iPSC­MSC­DLX3 compared with iPSC­MSC­GFP on day 7 (P<0.05). The number of mineralized nodules in iPSC­MSC­DLX3 was increased compared with that in iPSC­MSC­GFP on day 14 (P<0.05). Thus, the present study demonstrated that DLX3 serves a negative role in proliferation, but a positive role in the osteogenic differentiation of iPSC­MSCs. This may provide novel insight for treating osteoporosis.

Bone-Targeted Extracellular Vesicles from Mesenchymal Stem Cells for Osteoporosis Therapy.

BACKGROUND: Current drugs used for osteoporosis therapy show strong adverse effects. Stem cell-derived extracellular vesicles (EVs) provide another choice for osteoporosis therapy. Mouse mesenchymal stem cells (mMSCs)-derived EVs promote bone regeneration; however, their clinical application is limited due to non-specific tissue targeting. Alendronate specifically targets bone tissue via hydroxyapatite. Therefore, EVs were combined with alendronate to generate Ale-EVs by "click chemistry" to facilitate EVs targeting bone via alendronate/hydroxyapatite binding. METHODS: Ale-EVs were characterized based on size using dynamic light scattering analysis and morphology was visualized by transmission electron microscopy. Hydroxyapatite affinity of Ale-EVs was detected by flow cytometry. Bone targeting of Ale-EVs was tested by ex vivo fluorescent imaging. Cell viability was assessed by using WST-8 reduction assay kit for testing the ability of Ale-EVs to promote mMSCs proliferation. Alkaline phosphatase experiment was used to detect ability of Ale-EVs to promote differentiation of mouse mesenchymal stem cells in vitro. Western blotting and Q-PCR assay were used to detect the early marker of osteogenic differentiation. Antiosteoporotic effects of Ale-EVs were detected in ovariectomy (OVX)-induced osteoporosis rat model. The safety of the Ale-EVs in vivo was measured by H&E staining and serum markers assay. RESULTS: In vitro, Ale-EVs had high affinity with hydroxyapatite. Also, ex vivo data indicated that Ale-EVs-DiD treatment of mice induced strong fluorescece in bone tissues compared with EVs-DiD group. Furthermore, results suggested that Ale-EVs promoted the growth and differentiation of mouse MSCs. They also protected against osteoporosis in ovariectomy (OVX)-induced osteoporotic rats. Ale-EVs were well tolerated and no side effects were found, indicating that Ale-EVs specifically target bone and can be used as a new therapeutic in osteoporosis treatment. CONCLUSION: We used the Ale-N3 to modify mouse mesenchymal stem cells-derived extracellular vesicles by copper-free "click chemistry" to generate a Ale-EVs system. The Ale-EVs had a high affinity for bone and have great potential for clinical applications in osteoporosis therapy with low systemic toxicity.

Efficient miRNA Inhibitor Delivery with Graphene Oxide-Polyethylenimine to Inhibit Oral Squamous Cell Carcinoma.

BACKGROUND: MicroRNAs (miRNAs) are widely believed to be promising targets for oral squamous cell carcinoma (OSCC) gene therapy. miR-214 has been identified as a promoter of OSCC aggression and metastasis. METHODS: Graphene oxide-polyethylenimine (GO-PEI) complexes were prepared and loaded with a miRNA inhibitor at different N/P ratios. The transfection efficiency of GO-PEI-inhibitor was tested in Cal27 and SCC9 cells. Moreover, the tumor inhibition ability of GO-PEI-inhibitor was measured in an OSCC xenograft mouse model by intratumoral injection. RESULTS: Here, we show that a GO-PEI complex efficiently delivers a miR-214 inhibitor into OSCC cells and controls the intracellular release of the miR-214 inhibitor. These results indicate that the GO-PEI-miR-214 inhibitor complex efficiently inhibited cellular miR-214, resulting in a decrease in OSCC cell invasion and migration and an increase in cell apoptosis by targeting PTEN and p53. In the xenograft mouse model, the GO-PEI-miR-214 inhibitor complex significantly prevented tumor volume growth. CONCLUSION: This study indicates that functionalized GO-PEI with low toxicity has promising potential for miRNA delivery for the treatment of OSCC.

Application of a Lateral Pedicled Cranial Bone Flap for the Treatment of Secondary Zygomaticomaxillary Defects.

This study aimed to evaluate the effect of laterally-based pedicled cranial bone flap (LBPCBF) for the repair of secondary zygomaticomaxillary defects. Between December 2014 and December 2016, 6 patients with unilateral zygomaticomaxillary defects were selected; of these, 5 had trauma, and 1 was exposed to titanium mesh in the infraorbital area due to radiotherapy following total maxillectomy for right maxillary squamous cell carcinoma. Preoperatively, 3 patients suffered from an intraoral vestibular groove fistula, 2 suffered from an extraoral fistula, and 1 from local exposure of titanium mesh. Surgical treatment was implemented in all 6 patients, of which, the 5 trauma patients underwent debridement, reduction, and fixation of periorbital fracture, followed by repair of the defects in the infraorbital margin, anterior wall of maxillary sinus, and zygomatic body with LBPCBF, and then, reconstruction of the orbital floor with titanium mesh. The other patient with exposed titanium mesh underwent repair of defects in the infraorbital margin and anterior wall of the maxillary sinus with LBPCBF after titanium mesh trimming. Postoperative review at 6 months revealed disappearance of intraoral fistula, wound healing, and improvement of facial deformity in all 6 patients, of which 2 patients demonstrated postoperative ectropion. The application of LBPCBF can simultaneously repair bone defects in the infraorbital margin, anterior wall of maxillary sinus, and zygomatic body, as well as, supplement the soft tissue, thereby indicating a satisfactory treatment effect.

Functionalization of SF/HAP Scaffold with GO-PEI-miRNA inhibitor Complexes to Enhance Bone Regeneration through Activating Transcription Factor 4.

Evidence indicates that microRNAs (miRNAs) play vital roles in regulating osteogenic differentiation and bone formation. Methods: Here, we show that a polyethyleneimine (PEI)-functionalized graphene oxide (GO) complex efficiently loaded with the miR-214 inhibitor is assembled into silk fibroin/hydroxyapatite (SF/HAP) scaffolds that spatially control the release of the miR-214 inhibitor. Results: SF/HAP/GO scaffolds with nanosized GO show high mechanical strength, and their hierarchical microporous structures promote cell adhesion and growth. The SF/HAP/GO-PEI scaffolds loaded with mir-214 inhibitor (SF/HAP/GPM) were tested for their ability to enhance osteogenic differentiation by inhibiting the expression of miR-214 while inversely increasing the expression of activating transcription factor 4 (ATF4) and activating the Akt and ERK1/2 signaling pathways in mouse osteoblastic cells (MC3T3-E1) in vitro. Similarly, the scaffolds activated the osteoblastic activity of endogenous osteoblast cells to repair critical-sized bone defects in rats without the need for loading osteoblast cells. Conclusion: This technology is used to increase osteogenic differentiation and mineralized bone formation in bone defects, which helps to achieve cell-free scaffold-based miRNA-inhibitor therapy for bone tissue engineering.

Toxicity Induced by Zirconia Oxide Nanoparticles on Various Organs After Intravenous Administration in Rats.

ZrO2-NPs are widely applied in industry, biomedicine and dentistry, e.g., foundry sands, refractories, ceramics dental prostheses, dental implant coatings and bone defect restorative materials. To date, little information is available on the potential adverse effects and toxic mechanism in human organs associated with exposure to ZrO2-NPs. The biodistribution of ZrO2-NPs and the consequent oxidative stress in the spleen, kidney, heart, brain, and lung at six time points after a single injection of ZrO2-NPs were examined. Histopathological and immunohistochemical changes were also examined. RNA-Seq analysis was conducted in organs with high ZrO2-NPs accumulations or obvious histopathological changes (brain and spleen). Exposure to the ZrO2-NPs led to persistent oxidative stress and cell proliferation promotion/inhibition in various organs. RNA-Seq results of the spleen and brain point to significant gene expression changes. Metabolism was identified as leading pathways in the spleen. This study proves ZrO2-NPs likely have negative impacts on various organs, and exhibit potential disease risks.

The impact of photofunctionalized gold nanoparticles on osseointegration.

OBJECTIVES: The aims of this study were to create a new surface topography using simulated body fluids (SBF) and Gold Nanoparticles (GNPs) and then to assess the influence of UV Photofunctionalization (PhF) on the osteogenic capacity of these surfaces. MATERIALS AND METHODS: Titanium plates were divided into six groups All were acid etched with 67% Sulfuric acid, 4 were immersed in SBF and 2 of these were treated with 10 nm GNPs. Half of the TiO2 plates were photofunctionalized to be compared with the non-PhF ones. Rat's bone marrow stem cells were seeded into the plates and then CCK8 assay, cell viability assay, immunofluorescence, and Scanning electron microscopy (SEM) were done after 24 hours. Gene expression analysis was done using real time quantitative PCR (qPCR) one week later to check for the mRNA expression of Collagen-1, Osteopontin and Osteocalcin. Alkaline phosphatase (ALP) activity was assessed after 2 weeks of cell seeding. RESULTS: Our new topography has shown remarkable osteogenic potential. The new surface was the most biocompatible, and the 10 nm GNPs did not show any cytotoxicity. There was a significant increase in bioactivity, enhanced gene expressions and ALP activity. CONCLUSIONS: GNPs enhances osteogenic differentiation of stem cells and Photofunctionalizing GNPs highly increases this. We have further created a novel highly efficient topography which highly enhances the speed and extent of osseointegration. This may have great potential for improving treatment outcomes for implant, maxillofacial as well as orthopedic patients.

Ectopic osteogenesis effect of antigen-extracted xenogeneic cancellous bone graft with chitosan/rhBMP-2/bFGF sequential sustained-release nanocapsules.

To explore the ectopic osteogenesis effect of sequential sustained release application of recombinant human bone morphogenic protein-2 (rhBMP-2) and basic fibroblast growth factor (bFGF). Antigen-extracted xenogeneic cancellous bone coupled with growth factor-loaded chitosan nanocapsules were implanted in rats in intramuscular site in accordance with the following experimental pattern: group A: simultaneous burst release of rhBMP-2 and bFGF; group B: simultaneous sustained release of rhBMP-2 and bFGF; group C: preferential burst release of rhBMP-2, then sustained release of bFGF; group D: preferential burst release of bFGF, then sustained release of rhBMP-2; group E: sustained release of rhBMP-2 alone; group F: sustained release of bFGF alone, blank control group G: antigen-extracted xenogeneic cancellous bone graft only; negative control group H: not filled with anything. Specimens were obtained after executing the animals at 2 and 4 weeks for general observation and weighing, calcium content detection, micro-CT scanning and bone parameter measurement analysis, H&E staining, ALP staining and CD34 staining. The materials weight of A-2, B-2, C-2, A-4, B-4, C-4, D-4 and E-4 were significantly higher than that of preoperative materials ( P < 0.05). The concentration of calcium of group B-4 was the highest (414.7 ± 12.03 mg/dl). Micro-CT scanning and bone parameter measurement analysis showed that the values of bone mineral density and trabecular thickness of group A, B, D, E at 4 weeks were both higher than the ones at 2 weeks ( P < 0.05), and both the bone mineral density (367.52 ± 11.64 mg/cc) and the trabecular thickness (126.17 ± 11.36 µm) of group B-4 were the highest. H&E staining showed that a large region of calcified cartilage and haemopoietic tissues were newly formed, especially in group B-4. ALP staining and CD34 staining showed the most positive expression region in group B-4. Therefore, we conclude that simultaneous sustained release of rhBMP-2 and bFGF is the ideal way to release drug, and has better inducement of antigen-extracted xenogeneic cancellous bone graft.

The Biocompatibility of Dental Graded Nano-Glass-Zirconia Material After Aging.

ᅟ: A graded nano-glass/zirconia (G/Z) system has been developed via the infiltration of nano-glass into a nano-zirconia surface, which is advantageous for robust core-veneer bonds. The aging issue is a key for yttrium-stabilized tetragonal zirconia polycrystals (Y-TZPs), and therefore, it is necessary to evaluate the influence of aging degradation on the biocompatibility of G/Z systems before their possible clinical application. Herein, such biocompatibility testing was performed with human gingival fibroblasts (HGFs) seeded onto unaged/aged G/Z and Y-TZP for 2-72 h. Assessments included an oral mucous membrane irritation test in conjunction with analyses of cell viability, cell adhesion, and oxidative stress responses. Significant metabolic decreases in aged G/Z- and Y-TZP-treated cells were observed at 72 h. G/Z did not elicit any significant differences in cell viability compared with Y-TZP over 72 h both before and after aging. The oxidative stress data for the aged G/Z- and Y-TZP-treated cells showed a significant increase at 72 h. The G/Z specimens did not elicit any significant differences in ROS production compared with Y-TZP over 72 h both before and after aging. The cell adhesion rates of both G/Z and Y-TZP increased significantly after aging. The cell adhesion rates of G/Z and Y-TZP were not significantly different before and after aging. According to the oral mucous membrane irritation test, scores for macroscopic and microscopic observations for both the aged G/Z and unaged G/Z sides were 0, demonstrating no consequent irritation. CONCLUSIONS: The excellent biocompatibility of G/Z indicates that it has potential for future clinical applications.

Treatment of intraoral ranulas with a two-incision fistula technique: the management of recurrence.

The two-incision fistula technique for the treatment of oral ranulas has recently been introduced to clinical practice. We reviewed 52 patients who had recurrences after this treatment, and explored the possible causes and underlying mechanisms. A total of 13/53 ranulas had recurred, so we repeated the operation, and one patient had the ranula and the sublingual gland resected. We found that the thin mucous membrane cracked at the double incisions, which led to the formation of a fistula and promoted the drainage of cystic fluid. The results indicated that the recurrence of ranulas after the two-incision fistula technique can be reduced further. To avoid recurrence, the technique should be adjusted slightly, depending on the type of ranula present.

Arglabin is a plant sesquiterpene lactone that exerts potent anticancer effects on human oral squamous cancer cells via mitochondrial apoptosis and downregulation of the mTOR/PI3K/Akt signaling pathway to inhibit tumor growth in vivo.

PURPOSE: To evaluate the anticancer effects and the underlying mechanism of arglabin on oral squamous cell carcinoma (OSCC) cells. METHODS: 4',6-Diamidino-2-phenylindole dihydrochloride (DAPI) and annexin V/propidium iodide (PI) staining were performed to evaluate apoptosis. Reactive oxygen species (ROS) levels and mitochondrial membrane potential (MMP) were examined by flow cytometry. Protein expression was assessed by western blot analysis. To examine the anticancer activity of arglabin in vivo, subcutaneous xenografts in nude mice were evaluated. RESULTS: Arglabin exhibited an IC50 of 10 µM in OSCC cells and induced apoptosis by inhibiting MMP and enhancing intracellular ROS levels. DAPI and annexin V/PI staining indicated apoptosis of OSCC cells induced by arglabin. Arglabin also downregulated the expression of key proteins in the mTOR/PI3K/Akt signaling pathway. In vivo evaluation showed that arglabin reduced the average tumor volumes and growth of xenografted tumors, indicative of its anticancer activity. CONCLUSIONS: Arglabin showed selective in vitro and in vivo anticancer activities against OSCC cells and is therefore a potential therapeutic agent for the management of OSCC.