A comparative study of microbial changes in dental plaque before and after single- and multiappointment treatments in patients with severe early childhood caries.

BACKGROUND: The status of dental caries is closely related to changes in the oral microbiome. In this study, we compared the diversity and structure of the dental plaque microbiome in children with severe early childhood caries (S-ECC) before and after general anaesthesia and outpatient treatment. METHODS: Forty children aged 3 to 5 years with S-ECC who had completed whole-mouth dental treatment under general anaesthesia (C1) or in outpatient settings (C2) were selected, 20 in each group. The basic information and oral health status of the children were recorded, and the microbial community structure and diversity of dental plaque before treatment (C1, C2), the day after treatment(C2_0D), 7 days after treatment (C1_7D, C2_7D), 1 month after treatment (C1_1M, C2_1M), and 3 months after treatment (C1_3M, C2_3M) were analysed via 16 S rRNA high-throughput sequencing technology. RESULTS: (1) The alpha diversity test showed that the flora richness in the multiappointment group was significantly greater at posttreatment than at pretreatment (P < 0.05), and the remaining alpha diversity index did not significantly differ between the 2 groups (P > 0.05). The beta diversity analysis revealed that the flora structures of the C1_7D group and the C2_3M group were significantly different from those of the other time points within the respective groups (P < 0.05). (2) The core flora existed in both the pre- and posttreatment groups, and the proportion of their flora abundance could be altered depending on the caries status of the children in both groups. Leptotrichia abundance was significantly (P < 0.05) lower at 7 days posttreatment in both the single- and multiappointment groups. Corynebacterium and Corynebacterium_matruchotii were significantly more abundant in the C1_1M and C1_3M groups than in the C1 and C1_7D groups (P < 0.05). Streptococcus, Haemophilus and Haemophilus_parainfluenzae were significantly more abundant in the C1_7D group than in the other groups (P < 0.05). CONCLUSION: A single session of treatment under general anaesthesia can cause dramatic changes in the microbial community structure and composition within 7 days after treatment, whereas treatment over multiple appointments may cause slow changes in oral flora diversity.

Prediction of cyanidin 3-rutinoside content in Michelia crassipes based on near-infrared spectroscopic techniques.

Currently the determination of cyanidin 3-rutinoside content in plant petals usually requires chemical assays or high performance liquid chromatography (HPLC), which are time-consuming and laborious. In this study, we aimed to develop a low-cost, high-throughput method to predict cyanidin 3-rutinoside content, and developed a cyanidin 3-rutinoside prediction model using near-infrared (NIR) spectroscopy combined with partial least squares regression (PLSR). We collected spectral data from Michelia crassipes (Magnoliaceae) tepals and used five different preprocessing methods and four variable selection algorithms to calibrate the PLSR model to determine the best prediction model. The results showed that (1) the PLSR model built by combining the blockScale (BS) preprocessing method and the Significance multivariate correlation (sMC) algorithm performed the best; (2) The model has a reliable prediction ability, with a coefficient of determination (R2) of 0.72, a root mean square error (RMSE) of 1.04%, and a residual prediction deviation (RPD) of 2.06. The model can be effectively used to predict the cyanidin 3-rutinoside content of the perianth slices of M. crassipes, providing an efficient method for the rapid determination of cyanidin 3-rutinoside content.

A pseudo-Double-Network Hydrogel Built upon Layered Double Hydroxides with Self-Strengthening Properties.

While great achievements have been made in the development of mechanically robust nanocomposite hydrogels, incorporating multiple interactions on the bases of two demensional inorganic cross-linkers to construct self-strengthening hydrogels has rarely been investigated. To this end, we propose here a new method for the coupling the dynamic covalent bonds and non-covalent interactions within a pseudo double-network system. The pseudo first network, formed through the Schiff Base reation between Tris-modified layered double hydroxides (Tris-LDHs) and oxidized dextran (ODex), is linked to the second network built upon non-covalent interactions between Tris-LDHs and poly(acrylamide-co-2-acrylamido-2-methyl-propanesulfonate) (p-(AM-co-AMPS). The swelling and mechanical properties of the resulting hydrogels have been investigated as a function of the ODex and AMPS contents. The as-prepared hydrogel can swell to 420 times of its original size and retain more than 99.9 wt.% of water. Mechanical tests show that the hydrogel can bear 90 % of compression and is able to be stretched to near 30 times of its original length. Cyclic tensile tests reveal that the hydrogels are capable of self-strengthening after mechanical training. The unique energy dissipation mechanism based on the dynamic covalent and non-covalent interactions is considered to be responsible for the outstanding swelling and mechanical performances.

PRMD: an integrated database for plant RNA modifications.

The scope and function of RNA modifications in model plant systems have been extensively studied, resulting in the identification of an increasing number of novel RNA modifications in recent years. Researchers have gradually revealed that RNA modifications, especially N6-methyladenosine (m6A), which is one of the most abundant and commonly studied RNA modifications in plants, have important roles in physiological and pathological processes. These modifications alter the structure of RNA, which affects its molecular complementarity and binding to specific proteins, thereby resulting in various of physiological effects. The increasing interest in plant RNA modifications has necessitated research into RNA modifications and associated datasets. However, there is a lack of a convenient and integrated database with comprehensive annotations and intuitive visualization of plant RNA modifications. Here, we developed the Plant RNA Modification Database (PRMD; http://bioinformatics.sc.cn/PRMD and http://rnainformatics.org.cn/PRMD) to facilitate RNA modification research. This database contains information regarding 20 plant species and provides an intuitive interface for displaying information. Moreover, PRMD offers multiple tools, including RMlevelDiff, RMplantVar, RNAmodNet and Blast (for functional analyses), and mRNAbrowse, RNAlollipop, JBrowse and Integrative Genomics Viewer (for displaying data). Furthermore, PRMD is freely available, making it useful for the rapid development and promotion of research on plant RNA modifications.

Genetic analysis and elite tree selection of the main resin components of slash pine.

Pine resin, as a natural material, has been widely used in food, pharmaceutical, and chemical industries. Slash pine (Pinus elliottii Engelm var. elliottii) is the primary tree species for resin tapping due to its high resin yield, low resin crystallization rate, and high turpentine content. Current researches focuse on the targeted improvement of several significant components to meet industrial needs rather than just resin yield. The objective of this study was to examine the genetic variation and correlation of genetic and phenotype for four main resin components (α pinene, ß pinene, abietic acid, and levoprimaric acid) of 219 half-sib progenies from 59 families. The results showed that the levopimaric acid had the largest content (mean value = 21.63%), while the ß pinene content had the largest variation coefficient (CV = 0.42). The α pinene content has the highest heritability (h2 = 0.67), while levopimaric acid has the lowest heritability (h2 = 0.51). There was a significant negative correlation between α pinene and the other three components and a significant positive correlation between ß pinene and the two diterpenes. The family ranking and genetic gain suggested that it is possible to improve the contents of main resin components of slash pine through genetic breeding selection.

Prediction and Comparisons of Turpentine Content in Slash Pine at Different Slope Positions Using Near-Infrared Spectroscopy.

Pine resin is one of the best known and most exploited non-wood products. Resin is a complex mixture of terpenes produced by specialized cells that are dedicated to tree defense. Chemical defenses are plastic properties, and concentrations of chemical defenses can be adjusted based on environmental factors, such as resource availability. The slope orientation (south/sunny or north/shady) and the altitude of the plantation site have significant effects on the soil nutrient and the plant performance, whereas little is known about how the slope affects the pine resin yield and its components. In total, 1180 slash pines in 18 plots at different slope positions were established to determine the effects on the α- and ß-pinene content and resin production of the slash pine. The near-infrared spectroscopy (NIR) technique was developed to rapidly and economically predict the turpentine content for each sample. The results showed that the best partial least squares regression (PLS) models for α- and ß-pinene content prediction were established via the combined treatment of multiplicative scatter correction-significant multivariate correlation (MSC-sMC). The prediction models based on sMC spectra for α- and ß-pinene content have an R2 of 0.82 and 0.85 and an RMSE of 0.96 and 0.82, respectively, and they were successfully implemented in turpentine prediction in this research. The results also showed that a barren slope position (especially mid-slope) could improve the α-pinene and ß-pinene content and resin productivity of slash pine, and the ß-pinene content in the resin had more variances in this research.

A transcriptome-based association study of growth, wood quality, and oleoresin traits in a slash pine breeding population.

Slash pine (Pinus elliottii Engelm.) is an important timber and resin species in the United States, China, Brazil and other countries. Understanding the genetic basis of these traits will accelerate its breeding progress. We carried out a genome-wide association study (GWAS), transcriptome-wide association study (TWAS) and weighted gene co-expression network analysis (WGCNA) for growth, wood quality, and oleoresin traits using 240 unrelated individuals from a Chinese slash pine breeding population. We developed high quality 53,229 single nucleotide polymorphisms (SNPs). Our analysis reveals three main results: (1) the Chinese breeding population can be divided into three genetic groups with a mean inbreeding coefficient of 0.137; (2) 32 SNPs significantly were associated with growth and oleoresin traits, accounting for the phenotypic variance ranging from 12.3% to 21.8% and from 10.6% to 16.7%, respectively; and (3) six genes encoding PeTLP, PeAP2/ERF, PePUP9, PeSLP, PeHSP, and PeOCT1 proteins were identified and validated by quantitative real time polymerase chain reaction for their association with growth and oleoresin traits. These results could be useful for tree breeding and functional studies in advanced slash pine breeding program.

The chloroplast genome sequence and characteristic analysis of Vitex negundo var. heterophylla (Franch.) Rehder.

Vitex negundo var. heterophylla (Franch.) Rehder is a common small shrub in northern China. In order to study the fine nectar characteristics and water and soil conservation characteristics of V. negundo, the analysis of chloroplast genome would provide theoretical basis for economic development and germplasm utilization of V. negundo. The chloroplast genome sequence (accession number MW366787) of V. negundo was accepted by high-throughput sequencing technology using a plant from Jiulongshan, Mentougou District, Beijing, China. The total length of the chloroplast genome is 154,438 bp, and the A, T, C and G content of the whole genome is 30.48, 31.26, 19.42, and 18.84%, respectively. The phylogenetic analysis of 16 Verbenaceae plants (including V. negundo) with Arabidopsis thaliana as the outgroup was carried out by the maximum likelihood method; and the result shows that V. negundo is relatively closed to Vitex rotundifolia.

Assessment of Epigenetic and Phenotypic Variation in Populus nigra Regenerated via Sequential Regeneration.

Somatic variation has been demonstrated in tissue culture regenerated plants of many species. In the genus Populus, phenotypic variation caused by changes in 5-methylcytosine within the plant genome have been reported. To date, the phenotypic and epigenetic stability of plants regenerated from sequential regeneration has not been tested in trees. In this study, we detected DNA methylation of CCGG sites in regenerated plants of five generations in Populus nigra using methylation-sensitive amplified polymorphisms, and evaluated their growth performance and physiological traits. About 10.86-26.80% of CCGG sites in the regenerated plant genome were demethylated and 5.50-8.45% were methylated, resulting in significantly lower DNA methylation levels among all regenerated plants than among donor plants. We detected a significant difference in methylation levels between first regeneration regenerated plants (G1) and those of the other four generations (G2-G5); there were no significant differences among the four later generations. Therefore, the dramatic decrease in DNA methylation levels occurred only in the first and second poplar regenerations; levels then stabilized later in the regeneration process, indicating that two regeneration events were sufficient to change the methylation statuses of almost all CCGG sites sensitive to regeneration. Differences in growth and physiological traits were observed between regenerated plants and donor plants, but were significant only among plants of certain generations. Significant correlations were detected between methylation level and transpiration rate, net photosynthetic rate, peroxidase activity, and instant water utilization efficiency, indicating the involvement of epigenetic regulation in this unpredictable phenotypic variation.

[The Mechanism of GREM1's Effect on Osteogenic/Odontogenic Differentiation of Stem Cells from Apical Papilla].

OBJECTIVE: To study the effect of bone morphogenetic protein (BMP) antagonist Gremlin 1 (GREM1) on the function of stem cells from apical papilla (SCAPs) and explore its mechanism. METHODS: After isolation and culturing of stem cells from apical papilla in vitro, immunofluorescent staining was done to examine the subcellular localization of GREM1 in SCAPs. Transfection with lentiviral GREM1 shRNA was done to knock-down the GREM1. The SCAPs were subjected to osteogenic induction in both the GREM1 knockdown group and the control group, and the knockdown effect of GREM1 was examined using real time-PCR and Western blot. Two groups of cells were collected and the alkaline phosphatase (ALP) activity was measured 7 d after osteogenic induction. Alizarin red staining was done 3 weeks after osteogenic/odontogenic induction and real time-PCR was done after 0, 1, 2, 3 weeks of osteogenic induction to examine the expression of osteogenic/odontogenic marker genes, including osteocalcin ( OCN), osteopontin ( OPN), bone sialoprotein ( BSP), dentin matrix protein 1 ( DMP1), dentin sialophosphoprotein ( DSPP) and and the critical transcription factor osterix ( OSX), Runt-related transcription factor 2 ( RUNX2), and distal-less homebox 2 ( DLX2). Two groups of cells were collected, and CCK-8 and CFSE assay were used to evaluate changes in cell proliferation. In addition, real time-PCR was used to examine the expression of senescence-related genes p53 and wide-type activated factor 1 ( Waf1), a regulatory factor of the cell cycle, stemness associated gene krupple-like factor 4 ( KLF4), and SRY related HMG box-2 ( SOX2), and the expression of bone morphogenetic protein ( BMP) 2, 4, 5, 6, 7, 9 after GREM1 knockdown. RESULTS: Immunofluorescence staining showed that the expression of GREM1 in the nucleus was higher than that in the cytoplasm. Real time-PCR and Western blot affirmed that GREM1 was knocked down steadily. The ALP activity of the GREM1 knockdown group was higher than that of the control group ( P<0.05), and the alizarin red staining was lighter than that of the control group. The expression of OCN and DMP1 increased in the first, second and third week, OPN was increased in the second week, BSP increased in the third week, DSPP increased in the first week, and the difference was statistically significant ( P<0.05). The key osteogenic transcription factors RUNX2, OSX, and DLX2 all increased at different stages, and the difference was statistically significant ( P<0.05). CCK-8 and CFSE assay showed that the proliferation ability of the GREM1 knockdown group decreased ( P<0.05). In the GREM1 knockdown group, the expression of BMP2, 6, and 7 increased, the expression of SOX2 and KLF4 increased, while the expression of p53 and Waf1 decreased ( P<0.05). CONCLUSIONS: The knockdown of GREM1 enhanced the osteogenic/odontogenic differentiation and stemness of SCAPs and inhibited the proliferation and senescence of SCAPs. Effects of GREM1 on the function of SCAPs maybe achieved through regulating the gene expression of BMP2, BMP6, and BMP7 at the mRNA level.

The role and mechanism of mitochondrial functions and energy metabolism in the function regulation of the mesenchymal stem cells.

Mesenchymal stem cells (MSCs) are multipotent cells that show self-renewal, multi-directional differentiation, and paracrine and immune regulation. As a result of these properties, the MSCs have great clinical application prospects, especially in the regeneration of injured tissues, functional reconstruction, and cell therapy. However, the transplanted MSCs are prone to ageing and apoptosis and have a difficult to control direction differentiation. Therefore, it is necessary to effectively regulate the functions of the MSCs to promote their desired effects. In recent years, it has been found that mitochondria, the main organelles responsible for energy metabolism and adenosine triphosphate production in cells, play a key role in regulating different functions of the MSCs through various mechanisms. Thus, mitochondria could act as effective targets for regulating and promoting the functions of the MSCs. In this review, we discuss the research status and current understanding of the role and mechanism of mitochondrial energy metabolism, morphology, transfer modes, and dynamics on MSC functions.

GREM1 inhibits osteogenic differentiation, senescence and BMP transcription of adipose-derived stem cells.

Purpose: Adipose-derived stem cells (ADSCs) are ideal for cell-based therapies to support bone regeneration. It is vital to understand the critical genes and molecular mechanisms involved in the functional regulation of ADSCs for enhancing bone regeneration. In the present study, we investigated the Gremlin 1 (GREM1) effect on ADSCs osteogenic differentiation and senescence.Materials and methods: The in vitro ADSCs osteogenic differentiation potential was evaluated by determining alkaline phosphatase (ALP) activity, mineralization ability, and the expression of osteogenic markers. Cell senescence is determined by SA-ß-gal staining, telomerase assay, and the expression of aging markers.Results: GREM1 overexpression in ADSCs reduced ALP activity and mineralization, inhibited the expression of osteogenic related genes OCN, OPN, DSPP, DMP1, and BSP, and key transcription factors, RUNX2 and OSX. GREM1 knockdown in ADSCs enhanced ALP activity and mineralization, promoted the expression of OCN, OPN, DSPP, DMP1, BSP, RUNX2, and OSX. GREM1 overexpression in ADSCs reduced the percent SA-ß-Gal positive cells, P16 and P53 expressions, and increased telomerase activity. GREM1 knockdown in ADSCs increased the percentage of SA-ß-Gal positive cells, P16 and P53 expressions, and reduced telomerase activity. Furthermore, GREM1 reduced the mRNA expression levels of BMP2, BMP6, and BMP7.Conclusions: In summary, our findings suggested that GREM1 inhibited ADSCs senescence and osteogenic differentiation and antagonized BMP transcription.

IGF2 enhanced the osteo-/dentinogenic and neurogenic differentiation potentials of stem cells from apical papilla.

OBJECTIVES: In dental tissue engineering, niche is important for maintaining stem cell function and regenerating the dental tissues. However, there is limited knowledge for the growth factors in niche to maintain the function of stem cells. In this study, we investigated the effect of IGF2, a growth factor in stem cells from apical papilla (SCAPs) niche, on differentiation and proliferation potentials of SCAPs. MATERIALS AND METHODS: Recombinant human IGF2 protein (rhIGF2) was used. Cell counting kit-8 assay, Carboxyfluorescein succinimidyl ester assay, alkaline phosphatase (ALP) activity, Alizarin Red staining, quantitative calcium analysis, immunofluorescence staining and real-time RT-PCR were performed to investigate the cell proliferation and differentiation potentials of SCAPs. And proteomic analysis was used to identify the differential secreted proteins. RESULTS: By ALP activity assay, we found that 5 ng/mL rhIGF2 might be the optimal concentration for treatment. Then, Alizarin Red staining, quantitative calcium analysis and osteogenesis-related gene expression results showed that 5 ng/mL rhIGF2 could enhance the osteo-/dentinogenic differentiation potentials in SCAPs. Immunofluorescence staining and real-time RT-PCR results showed that neurogenic markers were significantly induced by 5 ng/mL rhIGF2 in SCAPs. Then, CCK-8 assay and CFSE assay results showed that 5 ng/mL rhIGF2 could enhance the cell proliferation in SCAPs. Furthermore, proteomic analysis showed that IGF2 could induce some secreted proteins which function related to the osteogenesis, neurogenesis and cell proliferation. CONCLUSIONS: Our results identified that IGF2 might be the potential mediator in niche to promote SCAP function and dental tissue regeneration.

miRNA-101 Targets TGF-ßR1 to Retard the Progression of Oral Squamous Cell Carcinoma.

Despite the considerable knowledge on the involvement of microRNA-101 (miR-101) in the evolution of oral squamous cell carcinoma (OSCC), the underlying mechanisms remain obscure. In this study, miR-101 expression was markedly downregulated in the OSCC cell lines and tissues. Cell counting kit-8 (CCK-8), ethynyl deoxyuridine (EdU), and colony formation assays showed that miR-101 inhibited the proliferation of OSCC cells. Flow cytometry and caspase 3 activity assays indicated that miR-101 induced OSCC cell apoptosis. Transwell assays demonstrated that this miRNA also repressed OSCC cell migration and invasion. Moreover, tube formation assay showed that miR-101 abated the proangiogenesis of OSCC cells. Dual-luciferase reporter assay confirmed that miR-101 directly targeted transforming growth factor-ß receptor 1 (TGF-ßR1) in OSCC. Ectopic expression of TGF-ßR1 counteracted the effects of miR-101 on the OSCC cell characteristics. Thus, miR-101 significantly abolished the proliferation, motility, and proangiogenesis of OSCC cells and induced their apoptosis by targeting TGF-ßR1. These results imply the potential application of miR-101 in OSCC treatment.

IGFBP5 promotes angiogenic and neurogenic differentiation potential of dental pulp stem cells.

Dental stem cells for dental pulp regeneration have become a new strategy for pulpitis treatment. Angiogenesis and neurogenesis play a vital role in the pulp-dentin complex regeneration, and appropriate growth factors will promote the process of angiogenesis and neurogenesis. Insulin-like growth factor-binding protein 5 (IGFBP5) is involved in the regulation of tooth growth and development. A previous study showed that IGFBP5 enhanced osteo/odontogenic differentiation of dental stem cells. Our research intends to reveal the function of IGFBP5 in the angiogenic and neurogenic differentiation of human dental stem cells. Human dental pulp stem cells (DPSCs) were used in the present study. Lentiviral IGFBP5 shRNA was used to silence the IGFBP5. Retroviruses expressing Wild-type IGFBP5 were used to over-express IGFBP5. Angiogenic and neurogenic differentiation were carried out by in vitro study. Real-time RT-PCR and western blot results showed that over-expression of IGFBP5 upregulated the expressions of angiogenic markers, including VEGF, PDGFA and ANG-1, and neurogenic markers, including NCAM, TH, Nestin, ßIII-tubulin, and TH, in DPSCs. Moreover, microscope observation confirmed that over-expression of IGFBP5 enhanced neurosphere formation in DPSCs in size and amount. Immunofluorescence staining results showed that over-expression of IGFBP5 also prompted the percentage of Nestin and ßIII-tubulin positive neurospheres in DPSCs. While depletion of IGFBP5 downregulated the expressions of VEGF, PDGFA, ANG-1, NCAM, TH, Nestin, ßIII-tubulin, and TH, it decreased the neurosphere formation and percentage of Nestin and ßIII-tubulin positive neurospheres in DPSCs. In conclusion, our results revealed that IGFBP5 promoted angiogenic and neurogenic differentiation potential of DPSCs in vitro and provided the possible potential target for enhancing directed differentiation of dental stem cells and dental pulp-dentin functional regeneration.

The poplar pangenome provides insights into the evolutionary history of the genus.

The genus Populus comprises a complex amalgam of ancient and modern species that has become a prime model for evolutionary and taxonomic studies. Here we sequenced the genomes of 10 species from five sections of the genus Populus, identified 71 million genomic variations, and observed new correlations between the single-nucleotide polymorphism-structural variation (SNP-SV) density and indel-SV density to complement the SNP-indel density correlation reported in mammals. Disease resistance genes (R genes) with heterozygous loss-of-function (LOF) were significantly enriched in the 10 species, which increased the diversity of poplar R genes during evolution. Heterozygous LOF mutations in the self-incompatibility genes were closely related to the self-fertilization of poplar, suggestive of genomic control of self-fertilization in dioecious plants. The phylogenetic genome-wide SNPs tree also showed possible ancient hybridization among species in sections Tacamahaca, Aigeiros, and Leucoides. The pangenome resource also provided information for poplar genetics and breeding.

MiR-495/IGF-1/AKT Signaling as a Novel Axis Is Involved in the Epithelial-to-Mesenchymal Transition of Oral Squamous Cell Carcinoma.

PURPOSE: Increasing evidence suggests that aberrant expression of miR-495 is associated with the progression of various cancers. The aim of this study was to investigate the function and underlying mechanism of miR-495 in oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: OSCC specimens and oral cancer cell lines, as well as the OSCC microRNA expression profile from the Gene Expression Omnibus database, were used to detect the expression of miR-495 in OSCC. Cell proliferation, migration, and invasion assays were performed to analyze the function of miR-495. Bioinformatics and luciferase reporter assays were used to identify the target gene of miR-495. Pearson analysis was carried out to investigate the correlation between miR-495 and insulin-like growth factor 1 (IGF1) or AKT levels. Transfection of pcDNA3.1 vector and small interfering RNA was performed to overexpress or downregulate the expression of IGF1. OSCC xenografts in mice were constructed to validate the function and mechanism of miR-495 in vivo. RESULTS: MiR-495 was downregulated in OSCC tissues and cell lines, and it markedly inhibited cell proliferation, migration, and invasion, as well as epithelial-to-mesenchymal transition (EMT)-related proteins of OSCC cells. IGF1 was identified as a direct target gene of miR-495. Besides, AKT was confirmed to be regulated by miR-495/IGF-1 signaling, and miR-495 was negatively correlated with IGF1 and AKT in OSCC. In vivo, miR-495 inhibited the growth and EMT-related proteins of OSCC xenografts in mice. CONCLUSIONS: The miR-495/IGF-1/AKT signaling axis played a tumor-suppressive role in OSCC by regulating cell proliferation, invasion, and migration, as well as EMT.

AP2a enhanced the osteogenic differentiation of mesenchymal stem cells by inhibiting the formation of YAP/RUNX2 complex and BARX1 transcription.

OBJECTIVES: Bone regeneration by bone tissue engineering is a therapeutic option for bone defects. Improving the osteogenic differentiation of mesenchymal stem cells (MSCs) is essential for successful bone regeneration. We previously showed that AP2a enhances the osteogenic differentiation in MSCs. The present study investigated the mechanism of how AP2a regulates the direct differentiation. MATERIALS AND METHODS: Co-immunoprecipitation and ChIP assays were carried out to investigate the underlying mechanism in MSCs differentiation. The osteogenic differentiation potential was determined by mineralization ability and the expression of osteogenic marker in vitro and the in vivo bone-like tissue generation in nude mice. RESULTS: We show that AP2a can compete with RUNX2, a key transcription factor in osteogenic differentiation, to recruit YAP and release the inhibition of RUNX2 activity from YAP by forming YAP-AP2a protein complex. YAP-AP2a protein complex also interacts with the BARX1 promoter through AP2a, inhibit the transcription of BARX1. Moreover, BARX1 inhibits osteogenic differentiation of MSCs. CONCLUSIONS: Our discoveries revealed that AP2a may regulate the osteogenic differentiation in an indirect way through competing with RUNX2 to relieve the RUNX2 activity which inhibited by YAP, and also in a direct way via targeting the BARX1 and directly repressed its transcription. Thus, our discoveries shed new light on the mechanism of direct differentiation of MSCs and provide candidate targets for improving the osteogenic differentiation and enhancing bone tissue regeneration.

Influence of crocetin on high-cholesterol diet induced atherosclerosis in rats via anti-oxidant activity together with inhibition of inflammatory response and p38 MAPK signaling pathway.

The present study aimed to investigate the effect and possible mechanism of action of crocetin on the high cholesterol diet (HCD) induced atherosclerosis rat. The Wistar rats were used in the current investigation. The rats were divided into following group, Group I: control, Group II: HCD induced AS, Group III: AS + crocetin (25 mg/kg), Group IV: AS + crocetin (50 mg/kg) and Group V: AS + Simvastatin, respectively. AS was induced in the rats using the vitamin D3 and HCD. The rats received the pre-determined treatment for the 10 weeks. After the study period, the level of lipid profile, malonaldehyde (MDA) and superoxide dismutase (SOD) were also estimated. The proinflammatory cytokines viz., tumor necrosis factor (TNF)-α and interleukin (IL)-6 were scrutinized using the ELISA kits. We also estimated the expression of phosphorylated p38 (p-p38) MAPK using the Western blot techniques. The results revealed that the AS was successfully induced in the rats. The AS control group rats showed the modulated level of lipid profile, and decreased the level of the SOD and boost the level of the MDA as compared with the normal control. However, crocetin thrived in enhancing the lipid profile toward the standard value in the normal control group rats. The crocetin and simvastatin group rats significantly inhibited the expression of the p-p38 MAPK as compared to the AS group rats. In conclusion, the current investigation revealed that the crocetin reduced the HCD induced dyslipidemia in the Wistar rats, the possible mechanism of action may be connected to the antioxidative, down regulating of p-p38 MAPK and antiinflammatory effect by crocetin.