Injectable calcium phosphate cement integrated with BMSCs-encapsulated microcapsules for bone tissue regeneration.

Injectable calcium phosphate cement (CPC) offers significant benefits for the minimally invasive repair of irregular bone defects. However, the main limitations of CPC, including its deficiency in osteogenic properties and insufficient large porosity, require further investigation and resolution. In this study, alginate-chitosan-alginate (ACA) microcapsules were used to encapsulate and deliver rat bone mesenchymal stem cells (rBMSCs) into CPC paste, while a porous CPC scaffold was established to support cell growth. Our results demonstrated that the ACA cell microcapsules effectively protect the cells and facilitate their transport into the CPC paste, thereby enhancing cell viability post-implantation. Additionally, the ACA+CPC extracts were found to stimulate osteogenic differentiation of rBMSCs. Furthermore, results from a rat cranial parietal bone defect model showed that ACA microcapsules containing exogenous rBMSCs initially improved the in situ osteogenic potential of CPC within bone defects, providing multiple sites for bone growth. Over time, the osteogenic potential of the exogenous cells diminishes, yet the pores created by the microcapsules persist in supporting ongoing bone formation by recruiting endogenous cells to the osteogenic sites. In conclusion, the utilization of ACA loaded stem cell microcapsules satisfactorily facilitate osteogenesis and degradation of CPC, making it a promising scaffold for bone defect transplantation.

Uncovering the spatial characteristics of global net anthropogenic nitrogen input at high resolution and across 1.42 million lake basins.

Global Net Anthropogenic Nitrogen Input (NANI) at high resolution is crucial for assessing the impact of human activities on aquatic environments. Insufficient global high-resolution data sources and methods have hindered the effective examination of the global characteristics and driving forces of NANI. This study presents a general framework for calculating global NANI, providing estimates at a 5-arc-minute resolution and over 1.42 million lake basins in 2015. The results highlight the region near the Tropic of Cancer as a concentration area for high NANI and an inflection point for latitude-based accumulation variation. It also emphasizes the uneven distribution of NANI among continents, with Asia and Africa having the highest proportions, yet their high and low values are notably lower than those of Europe and South America. A similar pattern is observed in global lakes, where Asia has the smallest quantity and volume, but the highest NANI intensity. In contrast, North America and Europe have larger quantities and volumes but the lowest NANI intensity. The global distribution characteristics reveal a clustering pattern in high and low values, with 1.25 % of the area having a sum of NANI exceeding 20 %. The uncertainty analysis regarding model parameters indicates that continents with the highest NANI do not always exhibit the highest uncertainty. These results bridge the gap between global nitrogen sustainable management and anthropogenic nitrogen input. They support research on spatiotemporal changes and controlling factors of global river nutrient loads, as well as the impact of climatic factors on basin nitrogen loss and its variability.

Gingipain and oncostatin M synergistically disrupt kidney tight junctions in periodontitis-associated acute kidney injury.

BACKGROUND: Acute kidney injury (AKI) is characterized by rapid renal decline. Periodontitis, a chronic oral inflammatory disease, is increasingly associated with renal dysfunction. Although periodontitis is recognized as a contributor to kidney damage, the mechanisms linking it to AKI remain unclear. METHODS: This study explored the effects of Porphyromonas gingivalis (P. gingivalis) W83-infected periodontitis on AKI in C57BL/6J mice, using ischemia-reperfusion injury 55 days post-infection. Gingipain inhibitors, KYT-1 and KYT-36, were applied. Detection of P. gingivalis was performed using quantitative real-time polymerase chain reaction (qRT-PCR) and PCR, while transcriptome sequencing, qRT-PCR, immunohistochemistry, and immunofluorescence staining assessed renal damage. In vitro, HK-2 cells were exposed to P. gingivalis at a multiplicity of infection of 10 for 48 h, with inhibition by gingipain or oncostatin M (OSM). Disruption of tight junctions (TJs) was quantified using qRT-PCR, transepithelial electrical resistance, and cell counting kit-8 assays. RESULTS: Periodontitis worsened AKI, linked to P. gingivalis infection and renal TJ disruption in the kidney. P. gingivalis infection activated OSM expression, which correlated positively with gingipain. Significantly, OSM and gingipain might collaboratively contribute to the damage of renal TJs, with the reduced expression of TJ proteins. Suppressing gingipain activity presented itself as a protective strategy against the destruction of TJs and the attendant worsening of AKI due to periodontitis. CONCLUSIONS: Our study enhances the understanding of the interplay between periodontitis and AKI, highlighting the harmful impact of P. gingivalis in AKI.

Ginkgolide C attenuated Western diet-induced non-alcoholic fatty liver disease via increasing AMPK activation.

BACKGROUND: Non-alcoholic steatohepatitis (NASH) is a metabolic dysregulation-related disorder that is generally characterized by lipid metabolism dysfunction and an excessive inflammatory response. Currently, there are no authorized pharmacological interventions specifically designed to manage NASH. It has been reported that Ginkgolide C exhibits anti-inflammatory effects and modulates lipid metabolism. However, the impact and function of Ginkgolide C in diet-induced NASH are unclear. METHODS: In this study, mice were induced by a Western Diet (WD) with different doses of Ginkgolide C with or without Compound C (adenosine 5 '-monophosphate (AMP)-activated protein kinase (AMPK) inhibitor). The effects of Ginkgolide C were evaluated by assessing liver damage, steatosis, fibrosis, and AMPK expression. RESULTS: The results showed that Ginkgolide C significantly alleviated liver damage, steatosis, and fibrosis in the WD-induced mice. In addition, Ginkgolide C markedly improved insulin resistance and attenuated hepatic inflammation. Importantly, Ginkgolide C exerted protective effects by activating the AMPK signaling pathway, which was reversed by AMPK inhibition. CONCLUSION: Ginkgolide C alleviated NASH induced by WD in mice, potentially via activating the AMPK signaling pathway.

Cognitive decline in Sprague-Dawley rats induced by neuroplasticity changes after occlusal support loss.

BACKGROUND: Tooth loss is closely related to cognitive impairment, especially affecting cognitive functions involving hippocampus. The most well-known function of the hippocampus is learning and memory, and the mechanism behind is neuroplasticity, which strongly depends on the level of brain-derived neurotrophic factor (BDNF). While research has delved into the possible mechanisms behind the loss of teeth leading to cognitive dysfunction, there are few studies on the plasticity of sensory neural pathway after tooth loss, and the changes in related indicators of synaptic plasticity still need to be further explored. METHODS: In this study, the bilateral maxillary molars were extracted in Sprague-Dawley rats of two age ranges (young and middle age) to establish occlusal support loss model; then, the spatial cognition was tested by Morris Water Maze (MWM). Quantitative real-time PCR (qPCR) and Western Blotting (WB) were used to detect BDNF, AKT, and functional proteins (viz., PSD95 and NMDAR) of hippocampal synapses. Golgi staining was used to observe changes in ascending nerve pathway. IF was used to confirm the location of BDNF and AKT expressed in hippocampus. RESULTS: MWM showed that the spatial cognitive level of rats dropped after occlusal support loss. qPCR, WB, and IF suggested that the BDNF/AKT pathway was down-regulated in the hippocampus. Golgi staining showed the neurons of ascending sensory pathway decreased in numbers. CONCLUSION: Occlusal support loss caused plastic changes in ascending nerve pathway and induced cognitive impairment in rats by down-regulating BDNF and synaptic plasticity.

Prx1/PHB2 axis mediates mitophagy in oral leukoplakia cellular senescence.

BACKGROUND: Oral leukoplakia (OLK) is the most common oral potentially malignant disorder (OPMD), which can be malignantly transformed into oral squamous cell carcinoma (OSCC). Peroxiredoxin1(Prx1) has been predicted to bind to Prohibitin2 (PHB2), which confers to affect OLK progression; however, the mechanism of Prx1/PHB2 mediated mitophagy involved in OLK remains unclear. METHODS: This study aimed to explore the mechanism of the Prx1/PHB2 axis on senescence in OLK through mediating mitophagy. The positive rate of Ki67 and the expression of p21, p16, PHB2, and LC3 in human normal, OLK, and OSCC tissues were detected by immunohistochemical staining. The mitophagy and mitochondrial function changes were then analyzed in Prx1 knockdown and Prx1C52S mutations in dysplastic oral keratinocyte (DOK) cells treated with H2O2. In situ Proximity Ligation Assay combined with co-immunoprecipitation was used to detect the interaction between Prx1 and PHB2. RESULTS: Clinically, the positive rate of Ki67 progressively increased from normal to OLK, OLK with dysplasia, and OSCC. Higher p21, p16, PHB2, and LC3 expression levels were observed in OLK with dysplasia than in normal and OSCC tissues. In vitro, PHB2 and LC3II expression gradually increased with the degree of DOK cell senescence. Prx1/PHB2 regulated mitophagy and affected senescence in H2O2-induced DOK cells. Furthermore, Prx1C52S mutation specifically reduced interaction between Prx1 and PHB2. Prx1Cys52 is associated with mitochondrial reactive oxygen species (ROS) accumulated and cell cycle arrest. CONCLUSION: Prx1Cys52 functions as a redox sensor that binds to PHB2 and regulates mitophagy in the senescence of OLK, suggesting its potential as a clinical target.

Ox-LDL-induced CD80+ macrophages expand pro-atherosclerotic NKT cells via CD1d in atherosclerotic mice and hyperlipidemic patients.

Atherosclerosis is an inflammatory disease of blood vessels involving the immune system. Natural killer T (NKT) cells, as crucial components of the innate and acquired immune systems, play critical roles in the development of atherosclerosis. However, the mechanism and clinical relevance of NKT cells in early atherosclerosis are largely unclear. The study investigated the mechanism influencing NKT cell function in apoE deficiency-induced early atherosclerosis. Our findings demonstrated that there were higher populations of NKT cells and interferon-gamma (IFN-γ)-producing NKT cells in the peripheral blood of patients with hyperlipidemia and in the aorta, blood, spleen, and bone marrow of early atherosclerotic mice compared with the control groups. Moreover, we discovered that the infiltration of CD80+ macrophages and CD1d expression on CD80+ macrophages in atherosclerotic mice climbed remarkably. CD1d expression increased in CD80+ macrophages stimulated by oxidized low-density lipoprotein (ox-LDL) ex vivo and in vitro. Ex vivo coculture of macrophages with NKT cells revealed that ox-LDL-induced CD80+ macrophages presented lipid antigen α-Galcer (alpha-galactosylceramide) to NKT cells via CD1d, enabling NKT cells to express more IFN-γ. Furthermore, a greater proportion of CD1d+ monocytes and CD1d+CD80+ monocytes were found in peripheral blood of hyperlipidemic patients compared with that of healthy donors. Positive correlations were found between CD1d+CD80+ monocytes and NKT cells or IFN-γ+ NKT cells in hyperlipidemic patients. Our findings illustrated that CD80+ macrophages stimulated NKT cells to secrete IFN-γ via CD1d-presenting α-Galcer, which may accelerate the progression of early atherosclerosis. Inhibiting lipid antigen presentation by CD80+ macrophages to NKT cells may be a promising immune target for the treatment of early atherosclerosis.NEW & NOTEWORTHY This work proposed the ox-LDL-CD80+ monocyte/macrophage-CD1d-NKT cell-IFN-γ axis in the progression of atherosclerosis. The proinflammatory IFN-γ+ NKT cells are closely related to CD1d+CD80+ monocytes in hyperlipidemic patients. Inhibiting CD80+ macrophages to present lipid antigens to NKT cells through CD1d blocking may be a new therapeutic target for atherosclerosis.

Identification and verification on prognostic index of glioblastoma immune-related lncRNAs.

BACKGROUND: Glioblastoma (GBM) is the most common cause of primary brain malignancy. Recently, many immune-related long noncoding ribonucleic acids (ir-lncRNAs) are indicated to be closely related to the regulation of the immune microenvironment and immune cell infiltration of GBM. OBJECTIVES: Through the joint analysis of multiple public databases, key ir-lncRNAs in GBM were screened. The ir-lncRNAs were used to construct risk-scoring models and promote the development of novel GBM biomarkers. MATERIAL AND METHODS: In this study, we performed a three-way Venn analysis combined with a least absolute shrinkage and selection operator (LASSO) regression analysis on all lncRNAs in The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA) and Imm-Lnc datasets, and identified 10 ir-lncRNAs. Multivariate Cox analysis was used to calculate the coefficient and construct a risk-scoring model. RESULTS: By plotting calibration curves and receiver operating characteristic (ROC) curves, the model showed excellent prediction results. Based on the Tumor Immune Estimation Resource (TIMER) database, the correlation analysis showed that 10 ir-lncRNAs risk scores were related to immune cell infiltration. The enrichment analysis was subsequently performed, which showed that these ir-lncRNAs played an important role in the progression of GBM. Among the 10 lncRNAs, we found that AL354993.1 was highly expressed in GBM, had not been reported, and was shown to be closely related to GBM progression. CONCLUSIONS: In conclusion, the 10 ir-lncRNAs have the potential to predict the prognosis of GBM patients and may play a vital role in the progression of the disease.

Oridonin suppresses the growth of glioblastoma cells via inhibiting Hippo/YAP axis.

Glioma is a brain tumor that originates from brain or spine glial cells. Despite alternative treatments, the overall survival rate remains low. Oridonin (ORI) is purified from the Chinese herb Rabdosia rubescens, which has exhibited positive effects on tumors. This study aimed to investigate the effect of ORI on U87MG glioblastoma cells and whether the Hippo/YAP-related signaling pathway was involved. Malignant glioblastoma U87MG cells and male athymic nude mice (BALB/cnu/nu) were used as the experimental models. The YAP inhibitor Verteporfin (VP) and the overexpression of YAP were used to investigate its potential relation with glioma. Here, we found that ORI inhibited cell proliferation and promoted cell apoptosis in a dose-dependent manner in U87MG cells. Moreover, ORI inhibited Bcl-2, YAP, and c-Myc protein expression but increased Bax, caspase-3, and p-YAP protein expression. Furthermore, the effect of ORI was also confirmed in a mouse model bearing glioma. ORI reversed the effect of overexpression of YAP. Collectively, oridonin suppressed glioblastoma oncogenesis via the Hippo/YAP signaling pathway and could be a potential therapeutic target in the treatment of glioblastoma.

Effect of RNA-binding proteins on osteogenic differentiation of bone marrow mesenchymal stem cells.

Tissue regeneration mediated by mesenchymal stem cells (MSCs) is an ideal way to repair bone defects. RNA-binding proteins (RBPs) can affect cell function through post-transcriptional regulation. Exploring the role of RBPs in the process of osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) is helpful to find a key method to promote the osteogenic efficiency of BMSCs. By reviewing the literature, we obtained a differentially expressed mRNA dataset during the osteogenic differentiation of BMSCs and a human RBP dataset. A total of 82 differentially expressed RBPs in the osteogenic differentiation of BMSCs were screened by intersection of the two datasets. Functional analysis showed that the differentially expressed RBPs were mainly involved in RNA transcription, translation and degradation through the formation of spliceosomes and ribonucleoprotein complexes. The top 15 RBPs determined by degree score were FBL, NOP58, DDX10, RPL9, SNRPD3, NCL, IFIH1, RPL18A, NAT10, EXOSC5, ALYREF, PA2G4, EIF5B, SNRPD1 and EIF6. The results of this study demonstrate that the expression of many RBPs changed during osteogenic differentiation of BMSCs.

Prognostic model and treatment choices for patients with primary intracranial central nervous system lymphoma: A population-based study.

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a non-Hodgkin lymphoma that occurs in the CNS. With the advancement of medical care, its prognosis and treatment have also undergone tremendous changes. This study aimed to construct a prognostic model and compare the effects of different treatments for intracranial PCNSL. METHODS: Cases diagnosed as PCNSL between 2004 and 2015 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. Data were analyzed using Kaplan-Meier method and Cox regression analysis. Nomogram was built and validated using the R program. RESULTS: A total of 2861 PCNSL patients were included in the analysis. Age, year of diagnosis, surgery and chemotherapy were independent predictors for both overall survival (OS) and cancer-specific survival (CSS). A nomogram was established to predict 3-, 5- and 10-year OS and CSS for patients. Receiver operating characteristic (ROC) curves and decision curve analysis (DCA) showed the nomogram had good predictive performance and clinical application value. We also revealed that gross total resection had significantly better OS and CSS than biopsy alone (P < 0.001). Patients who received only chemotherapy had the best prognosis and did not benefit from additional radiotherapy. CONCLUSION: We developed a nomogram to predict patient survival rates based on independent predictors. It is an effective tool to help clinicians make survival predictions. Our results showed that patients can benefit from gross total resection of tumor, if it is feasible, and chemotherapy. The role of radiotherapy remained to be further assessed.

Residual periodontal ligament in the extraction socket promotes the dentin regeneration potential of DPSCs in the rabbit jaw.

BACKGROUND: Because of the low regeneration efficiency and unclear underlying molecular mechanism, tooth regeneration applications are limited. In this study, we explored the influence of residual periodontal ligament on the dentin regeneration potential of dental pulp stem cells (DPSCs) in the jaw. METHODS: To establish a tooth regeneration model, the incisors of New Zealand white rabbits were extracted while preserving residual periodontal ligament, followed by the implantation of DPSCs. After 3 months, micro-computed tomography (micro-CT), stereomicroscopy and scanning electron microscopy (SEM) were used to observe the volume, morphology and microstructure of regenerated tissue. Histological staining and immunostaining analyses were used to observe the morphological characteristics and expression of the dentin-specific proteins DMP1 and DSPP. To explore the mechanism, DPSCs and periodontal ligament stem cells (PDLSCs) were cocultured in vitro, and RNA was collected from the DPSCs for RNA-seq and bioinformatic analysis. RESULTS: The results of micro-CT and stereomicroscopy showed that the number of sites with regeneration and the volume of regenerated tissue in the DPSCs/PDL group (6/8, 1.07 ± 0.93 cm3) were larger than those in the DPSCs group (3/8, 0.23 ± 0.41 cm3). The results of SEM showed that the regenerated dentin-like tissue in the DPSCs and DPSCs/PDL groups contained dentin tubules. Haematoxylin and eosin staining and immunohistochemical staining indicated that compared with the DPSCs group, the DPSCs/PDL group showed more regular regenerated tissue and higher expression levels of the dentin-specific proteins DMP1 and DSPP (DMP1: P = 0.02, DSPP: P = 0.01). RNA-seq showed that the coculture of DPSCs with PDLSCs resulted in the DPSCs differentially expressing 427 mRNAs (285 upregulated and 142 downregulated), 41 lncRNAs (26 upregulated and 15 downregulated), 411 circRNAs (224 upregulated and 187 downregulated), and 19 miRNAs (13 upregulated and 5 downregulated). Bioinformatic analysis revealed related Gene Ontology function and signalling pathways, including extracellular matrix (ECM), tumour necrosis factor (TNF) signalling and chemokine signalling pathways. CONCLUSIONS: Residual periodontal ligament in the extraction socket promotes the dentin regeneration potential of DPSCs in the jaw. RNA-seq and bioinformatic analysis revealed that ECM, TNF signalling and chemokine signalling pathways may represent the key factors and signalling pathways.

Molar loss further exacerbates 2-VO-induced cognitive impairment associated with the activation of p38MAPK/NFκB pathway.

Background: Vascular dementia is characterized by reduced cognitive function due to chronic cerebral hypoperfusion and has become a significant public health challenge as the global population ages. Recent studies suggested that molar loss, a common problem among the elderly, may trigger the development of cognitive decline. Our previous study found that the molar loss affected cognitive dysfunction, and the astrocytes in the hippocampus of chronic cerebral ischemia rats were affected, but the underlying mechanism is unclear. Methods: In this study, we established the animal model of molar loss with 2-VO rats and the Morris water maze was used to test the cognitive ability of rats in each group. The damage to neurons was observed via Nissl staining, and neuronal apoptosis was analyzed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay in the hippocampus of the rats. Quantitative Real-Time PCR and immunohistochemistry and histology (IHC) were used to detect the expression of p38MAPK, NFκB, caspase 3, and iNOS in the hippocampus. The astrocytes were detected by IHC and Immunofluorescence analysis for GFAP. After 2-VO MO surgery, rats were administered DMSO or p38MAPK inhibitor (SB203580) by intrathecal injection. Results: The Morris water maze test showed that the molar loss aggravated spatial memory learning ability with chronic cerebral ischemia decreased in the rats. The neuronal damage and more apoptotic cells were observed in the hippocampus of 2-VO rats. After the molar loss, the mRNA and protein expression of iNOS, p38MAPK, NFκB, and caspase 3 were further upregulated in 2-VO rats. Molar loss upregulated GFAP expression, and the p38MAPK-positive cells were labeled with the astrocyte marker GFAP. SB203580 reduced cognitive impairment and apoptosis of hippocampal neurons in 2-VO rats following the molar loss. Conclusion: Molar loss can aggravate cognitive impairment in 2-VO rats to a certain extent. The mechanism of molar loss exacerbating the cognitive decline in 2-VO rats may be associated with the activation of the p38MAPK-NFκB-caspase 3 signaling pathway, which induces neuronal apoptosis.

Physicochemical properties of bone marrow mesenchymal stem cells encapsulated in microcapsules combined with calcium phosphate cement and their ectopic bone formation.

Calcium phosphate bone cement (CPC) serves as an excellent scaffold material for bone tissue engineering owing to its good biocompatibility, injectability, self-setting property and three-dimensional porous structure. However, its clinical use is limited due to the cytotoxic effect of its setting reaction on cells and difficulties in degradation into bone. In this study, bone marrow mesenchymal stem cells (BMSCs) were encapsulated in alginate chitosan alginate (ACA) microcapsules and compounded with calcium phosphate bone cement. Changes in the compressive strength, porosity, injectability and collapsibility of CPC at different volume ratios of microcapsules were evaluated. At a 40% volume ratio of microcapsules, the composite scaffold displayed high porosity and injectability with good collapsibility and compressive strength. Cell live/dead double staining, Cell Counting Kit-8 (CCK-8) assays and scanning electron microscopy were used to detect the viability, proliferation and adhesion of cells after cell microcapsules were combined with CPC. The results revealed that cells protected by microcapsules proliferated and adhered better than those that were directly combined with CPC paste, and cell microcapsules could effectively form macropores in scaffold material. The composite was subsequently implanted subcutaneously on the backs of nude mice, and ectopic osteogenesis of the scaffold was detected via haematoxylin-eosin (H&E), Masson's trichrome and Goldner's trichrome staining. CPC clearly displayed better new bone formation function and degradability after addition of pure microcapsules and cell microcapsules. Furthermore, the cell microcapsule treatment group showed greater osteogenesis than the pure microcapsule group. Collectively, these results indicate that BMSCs encapsulated in ACA microcapsules combined with CPC composite scaffolds have good application prospects as bone tissue engineering materials.

Epigallocatechin gallate attenuates tumor necrosis factor (TNF)-α-induced inhibition of osteoblastic differentiation by up-regulating lncRNA TUG1 in osteoporosis.

Promoting osteoblast proliferation and differentiation contributes to the prevention and clinical treatment of osteoporosis. This study was to investigate the effect and mechanism of epigallocatechin gallate (EGCG) on tumor necrosis factor (TNF)-α-caused inhibition of osteoblastic differentiation. First, we cultured mouse embryo osteoblast precursor cells (MC3T3-E1) and induced by TNF-α (0, 2.5, 5, 10 ng/mL). The results revealed that TNF-α significantly inhibited the proliferation, ALP activity and mineralized nodule formation of MC3T3-E1 cells and promoted apoptosis. However, EGCG pretreatment significantly alleviated the inhibitory effect of TNF-α on MC3T3-E1. In addition, TNF-α significantly downregulated the expression of lncRNA TUG1 in MC3T3-E1, while EGCG upregulated the expression of lncRNA TUG1. After overexpression of lncRNA TUG1 in TNF-α-induced MC3T3-E1 cells, it could show similar effects as EGCG. However, interference with lncRNA TUG1 expression diminished the protective effect of EGCG on TNF-α-induced MC3T3-E1 cells. Finally, we found that EGCG inhibited TNF-α-induced activation of the Hippo/YAP signaling pathway, and that low expression of lncRNA TUG1 suppressed this effect. In conclusion, EGCG could suppress Hippo/YAP pathway activity by up-regulating lncRNA TUG1, ultimately improving TNF-α-caused inhibition of osteoblastic differentiation.

WDR5 promotes the tumorigenesis of oral squamous cell carcinoma via CARM1/ß-catenin axis.

Oral squamous cell carcinoma (OSCC) is a malignancy all over the world. WD repeat domain 5 (WDR5) is involved in cancer progression. In addition, it was reported that WDR5 is upregulated in head and neck cancer, while its role in OSCC is unknown. First, the expression of WDR5 in oral cancer tissues and cells was examined by qRT-PCR, IHF and western blot. CCK-8 assay was performed to test the cell viability. Cell migration was assessed by transwell assay. Knocking down WDR5 or CARM1 in oral cancer cells to detect its function on cancer growth, WDR5 and CARM1 were significantly upregulated in OSCC. Silencing WDR5 suppressed OSCC cell viability and migration. CARM1 level in OSCC cells was significantly inhibited by WDR5 downregulation, and CARM1 elevation could rescue the effect of WDR5 knockdown on tumorigenesis of OSCC. Moreover, silencing of WDR5 notably inactivated ß-catenin signaling pathway, while this phenomenon was restored by CARM1 overexpression. Silencing of WDR5 attenuated the tumorigenesis of OSCC via CARM1/ß-catenin axis. Thus, WDR5 might be a target for OSCC treatment.

The immunogenic reaction and bone defect repair function of ε-poly-L-lysine (EPL)-coated nanoscale PCL/HA scaffold in rabbit calvarial bone defect.

Tissue engineering is a promising strategy for bone tissue defect reconstruction. Immunogenic reaction, which was induced by scaffolds degradation or contaminating microorganism, influence cellular activity, compromise the efficiency of tissue engineering, or eventually lead to the failure of regeneration. Inhibiting excessive immune response through modulating scaffold is critical important to promote tissue regeneration. Our previous study showed that ε-poly-L-lysine (EPL)-coated nanoscale polycaprolactone/hydroxyapatite (EPL/PCL/HA) composite scaffold has enhanced antibacterial and osteogenic properties in vitro. However, the bone defect repair function and immunogenic reaction of EPL/PCL/HA scaffolds in vivo remains unclear. In the present study, three nanoscale scaffolds (EPL/PCL/HA, PCL and PCL/HA) were transplanted into rabbit paraspinal muscle pouches, and T helper type 1 (Th1), T helper type 2 (Th2), T helper type 17 (Th17), and macrophage infiltration were analyzed after 1 week and 2 weeks to detect their immunogenic reaction. Then, the different scaffolds were transplanted into rabbit calvarial bone defect to compare the bone defect repair capacities. The results showed that EPL/PCL/HA composite scaffolds decreased pro-inflammatory Th1, Th17, and type I macrophage infiltration from 1 to 2 weeks, and increased anti-inflammatory Th2 infiltration into the regenerated area at 2 weeks in vivo, when compared to PCL and PCL/HA. In addition, EPL/PCL/HA showed an enhanced bone repair capacity compared to PCL and PCL/HA when transplanted into rabbit calvarial bone defects at both 4 and 8 weeks. Hence, our results suggest that EPL could regulate the immunogenic reaction and promote bone defect repair function of PCL/HA, which is a promising agent for tissue engineering scaffold modulation.

RNA-seq reveals correlations between cytoskeleton-related genes and the osteogenic activity of mesenchymal stem cells on strontium loaded titania nanotube arrays.

Strontium loaded titania nanotube arrays (NTSr), as well as titania nanotube arrays (NT), have been regarded as effective coatings to promote bone regeneration on titanium implants, but an understanding of the full extent of early processes affected by such surface modifications is absent. To address this limitation, we performed RNA sequencing (RNA-seq) of Sprague-Dawley rat bone marrow mesenchymal stem cells (rBMMSCs) cultured on unmodified titanium sheets (Con), NT and NTSr specimens. By pairwise comparisons we found that NT and NTSr shared a majority of differentially expressed genes. The Gene Ontology (GO) analysis revealed that NT and NTSr up-regulated a bunch of genes that are annotated to the cytoskeleton. The results were supported by immunofluorescent, transmission electron microscopy (TEM) and western blotting assays. By inhibiting the cytoskeleton through pharmacological agents, the activities of alkaline phosphatase (ALP) on NT and NTSr were also suppressed. Informed by these results, we concluded that NT and NTSr specimens reorganized the cytoskeleton of cultured cells that may play a crucial role in osteogenic lineage commitment.

Effects of PPARs/20-HETE on the renal impairment under diabetic conditions.

Diabetic nephropathy (DN) is one of the most severe complications of diabetes mellitus. The pathomolecular events behind DN remain uncertain. Peroxisome proliferator-activated receptors (PPARs) play essential functions in the development of DN. Meanwhile, 20-hydroxyeicosatetraenoic acid (20-HETE) also plays central roles in the regulation of renal function. However, the relationship between PPARs and 20-HETE is rarely studied in DN. It was revealed in our study that both PPARs expression and CYP4A-20-HETE level were decreased under DN conditions in vivo and in vitro. Supplementation with bezafibrate, a PPAR pan-agonist, improved the damage of kidney in DN mice and in high glucose-induced NRK-52E cells, following the up-regulation of PPARs and the increase of CYP4A-20-HETE. PPARα antagonist (MK886), PPARß antagonist (GSK0660), and PPARγ antagonist (GW9662) reversed the protection of bezafibrate in NRK-52E, and abrogated the up-regulation of CYP4A-20-HETE produced by bezafibrate. Noteworthily, 20-HETE synthetase inhibitor, HET0016, also blocked the bezafibrate-mediated improvement of NRK-52E, and abolished the up-regulation of PPARs expression. Collectively, our data suggest that the concurrent down-regulation and interaction of PPARs and 20-HETE play crucial roles in the pathogenesis process of DN, and we provide a novel evidence that PPARs/20-HETE signaling may be served as a therapeutic target for DN patients.

The Adhesion and Invasion Mechanisms of Streptococci.

Streptococci are common human pathogens, colonizing multiple parts of the human body such as the upper respiratory tract, urethra, gastrointestinal tract, and oral cavity. Since they cause a variety of serious infections including heart diseases, meningitis, and oral diseases, streptococci are considered to play an important role in human diseases. Two critical steps in the pathogenesis of streptococcal infection are the adhesion to and invasion of host cells. This invasion is a strategy of streptococci to evade the host immune response and antibiotic therapy, as well as to penetrate to deeper tissues. To establish interaction between bacteria and host cells, adhesion is the initial step. To effectively adhere to host cells, streptococci express multiple adhesins, and the expression of different adhesins may lead to distinct mechanisms of subsequent invasion. The binding of streptococcal molecules to host proteins triggers downstream signal transduction in the host cells, leading to the uptake of bacteria. In this review, we present the adhesion and invasion mechanisms of different streptococci and the interaction with host cells leading to internalization.