Cellular Microbiology最新文献

In the cnidarian-dinoflagellate symbiosis, hosts show altered expression of genes involved in growth and proliferation when in the symbiotic state, but little is known about the molecular mechanisms that underlie the host’s altered growth rate. Using tissue-specific transcriptomics, we determined how symbiosis affects expression of cell cycle-associated genes, in the model symbiotic cnidarian Exaiptasia diaphana (Aiptasia). The presence of symbionts within the gastrodermis elicited cell-cycle arrest in the G₁ phase in a larger proportion of host cells compared with the aposymbiotic gastrodermis. The symbiotic gastrodermis also showed a reduction in the amount of cells synthesizing their DNA and progressing through mitosis when compared with the aposymbiotic gastrodermis. Host apoptotic inhibitors (Mdm2) were elevated, while host apoptotic sensitizers (c-Myc) were depressed, in the symbiotic gastrodermis when compared with the aposymbiotic gastrodermis and epidermis of symbiotic anemones, respectively. This indicates that the presence of symbionts negatively regulates host apoptosis, possibly contributing to their persistence within the host. Transcripts (ATM/ATR) associated with DNA damage were also downregulated in symbiotic gastrodermal tissues. In epidermal cells, a single gene (Mob1) required for mitotic completion was upregulated in symbiotic compared with aposymbiotic anemones, suggesting that the presence of symbionts in the gastrodermis stimulates host cell division in the epidermis. To further corroborate this hypothesis, we performed microscopic analysis using an S-phase indicator (EdU), allowing us to evaluate cell cycling in host cells. Our results confirmed that there were significantly more proliferating host cells in both the gastrodermis and epidermis in the symbiotic state compared with the aposymbiotic state. Furthermore, when comparing between tissue layers in the presence of symbionts, the epidermis had significantly more proliferating host cells than the symbiont-containing gastrodermis. These results contribute to our understanding of the influence of symbionts on the mechanisms of cnidarian cell proliferation and mechanisms associated with symbiont maintenance.

Objective. To investigate the effects and potential molecular mechanisms of LncRNA LINC01116 on proliferation, migration, and invasion of cervical cancer cells. Method(s). The content of miR-744-5p and LINC01116 in cervical cancer cells HeLa, SiHa, and C33a was detected by RT-PCR, the proliferative activity and clone number of SiHa cells were determined by MTT and clone formation assay, the number of invaded and migrated cells was determined by Transwell assay, the expressions of Cyclin D1 and MMP-2 in cells were detected by Western blot, and the activity of luciferase detected by dual-luciferase reporting system verified the regulatory relationship between LINC01116 and miR-744-5p. Result(s). Compared with human normal cervical epithelial cells Ect1/E6E7, the content of LINC01116 in cervical cancer cells HeLa, SiHa, and C33a was increased significantly [(1.04 ± 0.12) vs. (3.34 ± 0.38)/(4.48 ± 0.45)/(3.59 ± 0.45)] (P < 0.05), the content of miR-744-5p was decreased significantly [(0.98 ± 0.09) vs. (0.39 ± 0.04)/(0.34 ± 0.05)/(0.41 ± 0.05)] (P < 0.05). Silencing LINC01116 could inhibit the protein expression of Cyclin D1 [(0.68 ± 0.06) vs. (0.31 ± 0.04)] and MMP-2 [(0.74 ± 0.08) vs. (0.34 ± 0.05)] in SiHa cells, and inhibition of cell proliferation [(100.98 ± 7.89)% vs. (67.26 ± 6.14)%], clone formation ability [(180.31 ± 11.34) vs. (53.56 ± 6.18)], migration [(234.67 ± 15.31) vs. (98.46 ± 7.46)], and invasion [(134.83 ± 9.12) vs. (62.44 ± 5.34)]. LINC01116 targeted and negatively regulates the expression of miR-744-5p. Overexpression of miR-744-5p could inhibit the proliferation of cervical cancer SiHa cells [(101.64 ± 4.89)% vs. (62.34 ± 5.73)%], clone formation ability [(179.24 ± 12.34) vs. (47.67 ± 5.18)], migration [(241.06 ± 16.64) vs. (84.52 ± 7.57)], and invasion [(127.92 ± 8.16) vs. (65.24 ± 7.36)]. Inhibition of miR-744-5p reversed the effects of silencing LINC01116 on SiHa cell proliferation [(102.46 ± 7.64)% vs. (146.72 ± 12.23)%], clone formation ability [(47.64 ± 6.20) vs. (104.26 ± 8.64)], migration [(81.52 ± 7.42) vs. (153.64 ± 12.57)], and invasion [(69.12 ± 5.56) vs (94.31 ± 7.44)]. Conclusion(s). LncRNA LINC01116 inhibits proliferation, migration, and invasion of SiHa cells by targeting miR-744-5p, and LINC01116 is a potential molecular target for cervical cancer.

In this study, preoperative analysis of 1106 gastropathy patients with abdominal pain, vomiting, dyspepsia, and other symptoms was conducted. Independent sample t-test and correlation analysis and other ways were used for data cleansing and analysis. Findings were as follows: (1) Samples of different genders showed significance in PGI and PGII. The PGI and PGII values of women were significantly lower than those of men. (2) Age showed a significant positive correlation with PGI and PGII, which indicates that as the age increases, the PGI and PGII values become higher. (3) There was a significant negative correlation between age and abdominal pain. This signified that the younger the patient is, the more likely they will suffer abdominal pain. (4) PGI displayed a positive correlation with abdominal pain in the digestive tract (dyspepsia, gastrointestinal ulcers, gastrointestinal bleeding, etc.). It indicated that the higher the PGI value is, the more likely the patients will suffer abdominal pain and gastrointestinal diseases (dyspepsia, gastrointestinal ulcer, gastrointestinal hemorrhage, etc.). (5) PGII displayed a significant positive correlation with gastrointestinal diseases (dyspepsia, gastrointestinal ulcer, gastrointestinal hemorrhage, etc.) and a negative correlation with gastropathy (acute gastritis, chronic superficial gastritis, gastric ulcer, etc.). It indicated that the higher the value of PGII is, the more likely the patients will suffer symptoms of gastrointestinal diseases (dyspepsia, gastrointestinal ulcer, gastrointestinal hemorrhage, etc.), while less likely the patients will suffer gastropathy (acute gastritis, chronic superficial gastritis, gastric ulcer, etc.).

Purpose. To discuss effects of phosphatase and tensin homolog protein (PTEN)-mediated transforming growth factor-β (TGF-β)/Smad homologue 2 (Smad2) pathway on osteogenic differentiation in osteoporotic (OP) tibial fracture rats and bone marrow mesenchymal stem cell (BMSC) under tension. Methods. A tibial fracture model was established. The rats were divided into sham-operated group and model group, and tibia tissue was collected. Purchase well-grown cultured rat BMSC, and use the Flexercell in vitro cell mechanics loading device to apply tension. The expression of PTEN was detected by qRT-PCR. After the BMSCs were transfected with si-PTEN and oe-PTEN, the force was applied to detect cell differentiation. The expression of TGF-β/Smad2 protein was detected by Western blot. The formation of calcium nodules in BMSC was detected by alkaline phosphatase (ALP) staining and alizarin red (AR) staining. Results. The expression of PTEN was higher in the model group and tension MSC group, and the expression of TGF-β and Smad2 protein was lower. The expression of TGF-β and Smad2 protein in oe-PTEN group was lower than the oe-NC group and control group. The expression of TGF-β and Smad2 protein in si-PTEN group was higher than the si-NC group and control group. The results of ALP staining and AR staining also confirmed the above results. Conclusion. PTEN-mediated TGF-β/Smad2 pathway may play a key role in the osteogenic differentiation of OP tibial fracture rats. Downregulation of PTEN and upregulation of TGF-β/Smad2 signal can promote the osteogenic differentiation of BMSC under tension.

Supplementing amino acids was proven to relieve fatigue caused by exercise. This study explored the antifatigue effects of compound amino acid capsules (CAAC) on rats undergoing the forced swimming test (FST). CAAC augmented the endurance of FST in rats and alleviated the damage of skeletal muscle tissue and reduced the content of biochemical indicators in the serum. Furthermore, CAAC prevented skeletal muscle dysfunction in FST rats by modulating inflammation and oxidation reactions. After the treatment with CAAC, apoptosis and apoptosis-related protein and p-p65 were weakened, while the levels of SIRT1 and SIRT1/PGC-1α/Nrf2 pathway-related proteins were enhanced. The antifatigue properties of CAAC were associated with its antioxidant and anti-inflammatory capabilities, which were realized by activating the SIRT1/PGC-1α/Nrf2 pathway.

Background. Mouse model is one of the most widely used animal models for exploring the roles of human gut microbiota, a complex system involving in human immunity and metabolism. However, the structure of mouse gut bacterial community has not been explored at a large scale. To address this concern, the diversity and composition of the gut bacteria of 600 mice were characterized in this study. Results. The results showed that the bacteria belonging to 8 genera were found in the gut microbiota of all mouse individuals, indicating that the 8 bacteria were the core bacteria of mouse gut microbiota. The dominant genera of the mouse gut bacteria contained 15 bacterial genera. It was found that the bacteria in the gut microbiota were mainly involved in host’s metabolisms via the collaborations between the gut bacteria. The further analysis demonstrated that the composition of mouse gut microbiota was similar to that of human gut microbiota. Conclusion. Our study presented a bacterial atlas of mouse gut microbiota, providing a solid basis for investing the bacterial communities of mouse gut microbiota.

Chlamydia pneumoniae is a ubiquitous intracellular bacterium which infects humans via the respiratory route. The tendency of C. pneumoniae to persist in monocytes and macrophages is well known, but the underlying host-chlamydial interactions remain elusive. In this work, we have described changes in macrophage intracellular signaling pathways induced by C. pneumoniae infection. Label-free quantitative proteome analysis and pathway analysis tools were used to identify changes in human THP-1-derived macrophages upon C. pneumoniae CV6 infection. At 48-h postinfection, pathways associated to nuclear factor κB (NF-κB) regulation were stressed, while negative regulation on cell cycle control was prominent at both 48 h and 72 h. Upregulation of S100A8 and S100A9 calcium binding proteins, osteopontin, and purine nucleoside hydrolase, laccase domain containing protein 1 (LACC1) underlined the proinflammatory consequences of the infection, while elevated NF-κB2 levels in infected macrophages indicates interaction with the noncanonical NF-κB pathway. Infection-induced alteration of cell cycle control was obvious by the downregulation of mini chromosome maintenance (MCM) proteins MCM2-7, and the significance of host cell cycle regulation for C. pneumoniae replication was demonstrated by the ability of a cyclin-dependent kinase (CDK) 4/6 inhibitor Palbociclib to promote C. pneumoniae replication and infectious progeny production. The infection was found to suppress retinoblastoma expression in the macrophages in both protein and mRNA levels, and this change was reverted by treatment with a histone deacetylase inhibitor. The epigenetic suppression of retinoblastoma, along with upregulation of S100A8 and S100A9, indicate host cell changes associated with myeloid-derived suppressor cell (MDSC) phenotype.

Persistent Helicobacter pylori infection causes a variety of gastrointestinal diseases and even gastric cancer. H. pylori invades gastric epithelial cells to survive and proliferate, which is one of the key factors in persistent colonization. A Published study has confirmed that cells can eliminate intracellular H. pylori through xenophagy to maintain intracellular balance. However, a growing body of evidences indicate that H. pylori can inhibit xenophagy by miRNA through regulating the expression of key autophagy-related genes. Through western blot analysis, mRFP-GFP-LC3 transfection assay, and transmission electron microscopy, we found that H. pylori infection obstructed autophagy flux degradation stage in GES-1 cell lines. Gentamicin protection assay confirmed that inhibit xenophagy is benefit for intracellular H. pylori survive. miR-30c-1-3p and miR-30c-5p were upregulated in GES-1 cell lines after infecting with H. pylori, resulting in the negative regulation on xenophagy. Further studies through bioinformatics analysis and dual-luciferase reporter assays confirmed that ATG14 and ULK1 were the target genes of miR-30c-1-3p and that ATG12 was the target gene of miR-30c-5p. The overexpression of miR-30c-1-3p and miR-30c-5p reduces the expression of ATG14, ULK1, and ATG12 at mRNA level and also decreased intracellular H. pylori elimination in GES-1 cells. The above results suggested that the inhibition on xenophagy by miR-30c-1-3p and miR-30c-5p through ATG14, ULK1, and ATG12 targeting benefitted intracellular H. pylori in the evasion of xenophagy clearance.

The protozoan parasite Plasmodium, causative agent of malaria, initially invades and develops in hepatocytes where it resides in a parasitophorous vacuole (PV). A single invaded parasite develops into thousands of daughter parasites. Survival of the host cell is crucial for successful completion of liver stage development. Nuclear factor erythroid-derived 2-related factor 2 (NRF2) is a transcription factor known to induce transcription of cytoprotective genes when activated. Here we show that NRF2 is activated in Plasmodium berghei-infected hepatocytes. We observed that this NRF2 activation depends on PV membrane resident p62 recruiting KEAP1, the negative regulator of NRF2. Disrupting the NRF2 gene results in reduced parasite survival, indicating that NRF2 signaling is an important event for parasite development in hepatocytes. Together, our observations uncovered a novel mechanism of how Plasmodium parasites ensure host cell survival during liver stage development.