Long non-coding RNA MALAT1 promotes odontogenic differentiation of human dental pulp stem cells by impairing microRNA-140-5p-dependent downregulation of GIT2.

Accumulating research continues to highlight the notable role of microRNAs (miRs) and long non-coding RNAs (lncRNAs) as important regulators in the process of human dental pulp stem cell (hDPSCs) differentiation. The current study aimed to investigate the novel regulatory circuitry of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/miR-140-5p/G protein-coupled receptor (GPCR)-kinase 2 interacting protein 2 (GIT2) on the odontogenic differentiation of hDPSCs. In hDPSCs, miR-140-5p was downregulated during the odontogenic differentiation, which was verified to directly target GIT2. RNA crosstalk determined by dual-luciferase reporter and RNA pull-down assays revealed that MALAT1 could bind to miR-140-5p to upregulate the expression of GIT2. After that, the levels of MALAT1, miR-140-5p, and GIT2 in hDPSCs were up- or downregulated by exogenous transfection or lentivirus infection in order to investigate their effects on the differentiation of hDPSCs. It was observed that elevation of miR-140-5p or knockdown of GIT2 resulted in inhibited alkaline phosphatase (ALP) activity, expression of dentin sialophosphoprotein (DSPP), dentin matrix-protein-1 (DMP-1), and distal-less homeobox 3 (DLX3) as well as positive expression of desmoplakin (DSP) protein. The promotive effects of MALAT1 on odontogenic differentiation were diminished by restoration of miR-140-5p or inhibition of GIT2. Taken together, this study provides valuable evidence suggesting MALAT1 as a potential contributor to the odontogenic differentiation of hDPSCs.

HIV infection and microbial diversity in saliva.

Limited information is available about the effects of HIV and subsequent antiretroviral treatment on host-microbe interactions. This study aimed to determine the salivary microbial composition for 10 HIV-seropositive subjects, before and 6 months after highly active antiretroviral therapy (HAART), compared with that for 10 HIV-seronegative subjects. A conventional culture and two culture-independent analyses were used and consistently demonstrated differences in microbial composition among the three sets of samples. HIV-positive subjects had higher levels of total cultivable microbes, including oral streptococci, lactobacilli, Streptococcus mutans, and Candida, in saliva than did HIV-negative subjects. The total cultivable microbial levels were significantly correlated with CD4+ T cell counts. Denaturing gradient gel electrophoresis (DGGE), which compared the overall microbial profiles, showed distinct fingerprinting profiles for each group. The human oral microbe identification microarray (HOMIM) assay, which compared the 16S rRNA genes, showed clear separation among the three sample groups. Veillonella, Synergistetes, and Streptococcus were present in all 30 saliva samples. Only minor changes or no changes in the prevalence of Neisseria, Haemophilus, Gemella, Leptotrichia, Solobacterium, Parvimonas, and Rothia were observed. Seven genera, Capnocytophaga, Slackia, Porphyromonas, Kingella, Peptostreptococcaceae, Lactobacillus, and Atopobium, were detected only in HIV-negative samples. The prevalences of Fusobacterium, Campylobacter, Prevotella, Capnocytophaga, Selenomonas, Actinomyces, Granulicatella, and Atopobium were increased after HAART. In contrast, the prevalence of Aggregatibacter was significantly decreased after HAART. The findings of this study suggest that HIV infection and HAART can have significant effects on salivary microbial colonization and composition.

An enriched environment ameliorates maternal sleep deprivation-induced cognitive impairment in aged mice by improving mitochondrial function via the Sirt1/PGC-1α pathway.

BACKGROUND: Early life stress can cause cognitive impairment in aged offspring. Environmental enrichment (EE) is considered to be an effective non-pharmacological treatment for improving cognitive decline. The aim of this research was to evaluate the effect of EE, on cognitive impairment in aged offspring induced by maternal sleep deprivation (MSD) and the underlying mechanisms involved to investigate its potential value in clinical practice. METHODS: CD-1 damns were subjected or not to sleep deprivation during late gestation. Twenty-one days after birth, the offspring were assigned to standard or EE cages. At 18 months-old, the learning and memory function of the offspring mice was evaluated using Morris water maze. The hippocampal and prefrontal cortical levels of protein, gene, proinflammation cytokines, and oxidative stress indicators was examined by Western blot, real-time polymerase chain reaction, enzyme linked immunosorbent assay, and biochemical assays. RESULTS: Offspring in MSD group exhibited declined learning and memory abilities compared with control animals. Moreover, the hippocampal and prefrontal cortical levels of Sirtuin1 (Sirt1), peroxisome proliferator-activated receptor-gamma coactivator-1 alpha (PGC-1α), postsynaptic density protein-95, and synaptophysin were lower and those of proinflammation cytokines higher in the MSD group; meanwhile, the superoxide dismutase content was higher and the malondialdehyde and reactive oxygen species contents were lower. However, these deleterious changes were ameliorated by exposure to EE. CONCLUSIONS: EE attenuates MSD-induced cognitive impairment, oxidative stress, and neuroinflammation and reverses the reduction in synaptic protein levels in aged offspring mice via the Sirt1/PGC-1α pathway.

Relationships between rumination and different types of rapid eye movement sleep in patients with chronic insomnia disorder.

BACKGROUND AND OBJECTIVE: Rumination, a common factor of chronic insomnia disorder (CID) caused by cognitive-emotional arousal, is associated with an increased amount of rapid eye movement (REM) sleep. However, the specific subtypes, such as phasic REM and tonic REM, that contribute to the increased REM sleep have not been reported. This study aimed to determine the association between rumination and different REM sleep subtypes in patients with CID. METHODS: This study enrolled 35 patients with CID and 27 age- and sex-matched healthy controls. The Immersion-Rumination Questionnaire evaluated participants' rumination, and the Insomnia Severity Index was used to assess insomnia severity. Finally, polysomnography was used to monitor objective sleep quality and quantification of different types of REM. RESULTS: The CID patients had higher rumination scores than the healthy controls. They had a shorter REM sleep duration, less phasic REM, a lower percentage of phasic REM time, and a higher percentage of tonic REM time. Spectral analysis revealed that the patients affected by insomnia had higher ß power during REM sleep, higher ß and σ power during phasic REM sleep, and higher ß, and γ power during tonic REM sleep. Partial correlation analysis showed that rumination in the CID patients correlated negatively with the duration of phasic REM sleep. Additionally, rumination correlated negatively with δ power in REM sleep and positively with ß power in REM sleep, tonic REM sleep, phasic REM sleep, N3and N2 sleep in the patients with CID. CONCLUSION: The CID patients had stronger rumination, reduced total and phasic REM sleep, and the stronger rumination was, the shorter phasic REM was and the higher fast (ß) wave power in REM sleep.

Effects of Sleep Reactivity on Sleep Macro-Structure, Orderliness, and Cortisol After Stress: A Preliminary Study in Healthy Young Adults.

Purpose: To investigate changes and links of stress and high sleep reactivity (H-SR) on the macro-structure and orderliness of sleep and cortisol levels in good sleepers (GS). Patients and Methods: Sixty-two GS (18-40 years old) were recruited, with 32 in the stress group and 30 in the control group. Each group was further divided into H-SR and low SR subgroups based on the Ford Insomnia Response to Stress Test. All participants completed two nights of polysomnography in a sleep laboratory. Before conducting polysomnography on the second night, the stress group completed the Trier Social Stress Test and saliva was collected. Results: The duration of NREM sleep stages 1, 2 (N1, N2) and rapid eye movement sleep (REM) decreased, and the values of approximate entropy, sample entropy, fuzzy entropy, and multiscale entropy increased under stress and SR effects. Stress increased rapid eye movement density, and H-SR increased cortisol reactivity. Conclusion: Stress can damage the sleep and increase cortisol release in GS, especially those with H-SR. N1, N2 and REM sleep are more easily affected, while NREM sleep stage 3 sleep is relatively stable.

Landscape of Cell Communication in Human Dental Pulp.

The cellular atlas of the stroma is not well understood. Here, the cell populations in human dental pulp through single-cell RNA sequencing are profiled. Dental pulp stem cells, pulp cells, T cells, macrophages, endothelial cells, and glial cells are identified in human dental pulp. These cells support each other through sending growth signals. Based on the appearance of ligand-receptor pairs between two cell populations, pulp cells have the greatest communication with other cell types, while T cells have the least communication. In addition, T cells expressing TLR1, TLR2, and TLR4, and endothelial cells expressing TLR4, monitor bacterial invasion. These findings provide the census of normal dental pulp.

Analysis of the molecular mechanisms of targeted anti-caries DNA plasmid enhancing antibody responses by gene arrays.

BACKGROUND: The cytotoxic T lymphocyte antigen 4 (CTLA4) represents an attractive ligand for use in the targeting of antigens to dendritic cells (DCs). Studies have shown that CTLA4 targeted DNA vaccines induced accelerated and increased antibody responses compared to nontargeted vaccines. However, little is known about the molecular events on DCs after transfection with targeted DNA vaccines. METHODS: Here we constructed a green fluorescent protein (GFP)-labeled targeted anti-caries plasmid pMGJGLU/GFP and a GFP-labeled nontargeted anti-caries plasmid pCDGLU/GFP, compared the antibody responses they induced in mice, and investigated the gene expression profiles of DCs transfected with pMGJGLU/GFP and pCDGLU/GFP by gene array analysis. RESULTS: The data obtained showed that pMGJGLU/GFP induced accelerated and increased serum antibody responses in mice compared to pCDGLU/GFP. Overall, the expression levels of 28 genes were up-regulated in pMGJGLU/GFP transfected DCs compared to pCDGLU/GFP transfected DCs by gene array analysis. Real-time reverse transcriptase-polymerase chain reaction analysis on pMGJGLU/GFP transfected DCs and pCDGLU/GFP transfected DCs confirmed the up-regulation of the mRNA expression levels of seven selected genes. Notably, we identified the specific up-regulation of mRNA expression levels of cytokines Ccl17, Ccl19, and antigen presentation receptor Cd209a of pMGJGLU/GFP transfected DCs, suggesting a more rapid migration of DCs to lymph nodes and a T helper 2 biased immune response. CONCLUSIONS: In the present study, we confirmed our previous reports that CTLA4 targeted DNA vaccines could induce increased antibody responses compared to nontargeted vaccines. Ccl17, Ccl19 and Cd209a may play an important role in the enhanced immune responses.

[Efficacy of immune responses induced by anti-caries DNA vaccine-loaded bacterial ghost in mice].

OBJECTIVE: To develop an anti-caries DNA vaccine-loaded Salmonella typhimurium (St) ghost and enhance the efficacy of immune responses induced by anti-caries DNA vaccine via mucosal route. METHODS: Both pREP4 and PhiX gene E expression plasmids were transformed into StJ357 and then induced with isopropyl ß-D-1-thiogalactopyranoside (IPTG). The bacterial ghosts (BG) were collected after wash and loaded with anti-caries DNA vaccine pGJGLU/VAX. Mice were divided into four groups and immunized through the nasal route with pGJGLU/VAX-loaded BG (Group Ghost+pGJGLU/VAX), pVAX1-loaded BG (Group Ghost+pVAX1), pGJGLU/VAX-Bupivacaine complex (Group pGJGLU/VAX) and pVAX1-Bupivacaine complex (Group pVAX1), respectively. Enzyme-linked immunosorbent assay (ELISA) was used to evaluate the immune responses. RESULTS: ELISA results showed that group Ghost+pGJGLU/VAX had significantly higher level of specific anti-GLU SIgA antibody [(0.367 ± 0.086) A/µg] compared with group Ghost+pVAX1 [(0.122 ± 0.077) A/µg], Group pGJGLU/VAX[(0.068 ± 0.068) A/µg] or Group pVAX1[(0.089 ± 0.089) A/µg] (P = 0.028, 0.012 or 0.030, respectively). CONCLUSIONS: St ghost was developed successfully, which enhanced the efficacy of immune responses induced by anti-caries DNA vaccine pGJGLU/VAX via the nasal route.

Effect of protease inhibitors on the quantitative and qualitative assessment of oral microorganisms.

Protease inhibitor cocktails are routinely added to clinical samples used for proteomic studies to inactivate proteases. As these same samples are often used for microbial studies, we determined whether the addition of protease inhibitors could affect the quantitative or qualitative assessment of microbial profiles. Twenty-two saliva samples were collected and processed immediately with or without the addition of a protease inhibitor cocktail. Conventional cultivation methods were used to evaluate total bacterial growth. Total genomic DNA was isolated and a specific 16S rRNA gene-targeted region was PCR-amplified and separated by denaturing gradient gel electrophoresis. A combination of 1D sodium dodecyl sulfate polyacrylamide gel electrophoresis and LC-MS/MS methods was used to determine the effect of the protease inhibitors on the integrity of salivary proteins and peptides. Interestingly, no significant differences were observed in either the bacterial growth and composition or the integrity of salivary proteins between the two groups. Correlation coefficients between the paired samples for total cultivable microbiota (r(2) =0.847), total mutans streptococci (r(2) =0.898), total oral lactobacilli (r(2) =0.933), and total Streptococcus mutans (r(2) =0.870) also exceeded expected values. The results suggest that the addition of a protease inhibitor cocktail in saliva samples does not impact the growth of oral microbiota or compromise the ability to characterize its composition.