Wnt/Ca2+ pathway inhibits neural differentiation of human dental pulp stem cells in vitro.

Background/purpose: Dental pulp stem cells (DPSCs) have demonstrated significant potential for neuroregeneration. However, a full understanding of the specific mechanism underpinning the neural differentiation of DPSCs is still required. The Wnt signaling is crucial for the development of the embryonic neural system and the maintenance of adult neural homeostasis. This study aimed to investigate the role of the Wnt/Ca2+ pathway in the neural differentiation of human DPSCs (hDPSCs) and its modulation of the Wnt/ß-catenin pathway. Materials and methods: hDPSCs were cultured and divided into the control group and the neurogenic induction group (Neuro group). The mRNA and protein levels of neurogenic markers, Wnt/Ca2+, and Wnt/ß-catenin pathway indicators were determined using Quantitative real-time PCR and Western blotting. After inhibition of the Wnt/Ca2+ pathway using a WNT5A short hairpin RNA (shRNA) plasmid and subsequent neurogenic induction, neurogenic markers and Wnt/ß-catenin pathway indicators in the NC-sh-Neuro group and WNT5A-sh-Neuro group were determined using Quantitative real-time PCR and Western blotting. Results: Compared with the control group, the expression of the Wnt/Ca2+ pathway indicators (WNT5A, Frizzled 2, calmodulin-dependent protein kinase IIa, and nuclear factor of active T cells 1) decreased in the Neuro group. Conversely, the expression of WNT3A, total ß-catenin and active ß-catenin in the Wnt/ß-catenin pathway increased. Moreover, compared with the NC-sh-Neuro group, the WNT5A-sh-Neuro group exhibited a greater level of mature neural differentiation alongside elevated expression of the Wnt/ß-catenin pathway indicators. Conclusion: The Wnt/Ca2+ pathway inhibited neural differentiation of hDPSCs and has a negative effect on the Wnt/ß-catenin pathway in vitro.

The roles of protocadherin-7 in colorectal cancer cells on cell proliferation and its chemoresistance.

Despite the high mutation frequencies of KRAS, NRAS, and BRAF in colorectal cancer (CRC), there are no effective and reliable inhibitors for these biomarkers. Protocadherin-7 (PCDH7) is regarded as a potentially targetable surface molecule in cancer cells and plays an important role in their proliferation, metastasis, and drug resistance. However, the roles and underlying mechanisms of PCDH7 in CRC remain unclear. In the current study, we found that different colorectal cancer cells expressed PCDH7 over a wide range. The levels of PCDH7 expression were positively associated with cell proliferation and drug resistance in CRC cells but negatively correlated with the potential for cell migration and invasion. Our data indicated that PCDH7 mediated the resistance of CRC cells to ABT-263 (a small-molecule Bcl-2 inhibitor that induces apoptosis) by inhibiting cell apoptosis, which was supported by the downregulation of caspase-3, caspase-9, and PARP cleavage. We found that PCDH7 effectively promoted Mcl-1 expression at both mRNA and protein levels. Furthermore, PCDH7 activated the Wnt signaling pathway, which was confirmed by the increase in ß-catenin and c-Myc expression. Finally, and notably, S63845, a novel Mcl-1 inhibitor, not only effectively attenuated the inhibitory effect of PCDH7 on cell apoptosis induced by ABT-263 in vitro but also sensitized PCDH7-overexpressed CRC cell-derived xenografts to ABT-263 in vivo. Taken together, although PCDH7 inhibited the migration and invasion of CRC cells, it could facilitate the development of drug resistance in colorectal cancer cells by positively modulating Mcl-1 expression. The application of the Mcl-1 inhibitor S63845 could be a potential strategy for CRC chemotherapy, especially in CRC with high levels of PCDH7.

tRF-20-M0NK5Y93-induced MALAT1 promotes colon cancer metastasis through alternative splicing of SMC1A.

Recent studies have indicated that changes in the tumor microenvironment, such as hypoxia, result in the discrepant expression of noncoding small RNA tRNA-derived fragments (tRFs), affecting the phenotype of tumor metastasis. The biological function of tRFs in tumors has attracted increasing attention, but the mechanism by which tRFs mediate tumor metastasis has not been clarified. The direct regulatory relationship between tRFs and lncRNAs and the mechanism by which noncoding RNAs regulate alternative splicing are still unknown. In this study, the mechanism of tRF-mediated SMC1A alternative splicing and regulation of colon cancer metastasis was studied from multiple dimensions of cell, molecule, animal and clinical. Our present studies revealed that tRF-20-M0NK5Y93 inhibits colon cancer metastasis and that there is a significant correlation between the expression of tRFs, metastasis-associated lung adenocarcinoma transcript 1 (MALAT-1), and SRSF2 through complete transcriptional sequencing and bioinformatics. Mechanistic investigations indicated that tRFs could regulate the expression of MALAT-1 by binding to specific sites on MALAT-1. MALAT1, which is a long noncoding RNA (lncRNA), regulates alternative splicing of (structural maintenance of chromosomes 1A) SMC1A by interaction with SRSF2, resulting in discrepant expression of various isoforms, SMC1A001, SMC1A201, SMC1A005, and SMC1A003. Our findings revealed the interaction between different types of noncoding RNAs on alternative splicing, which is expected to be a novel potential therapeutic target.

Parachute-like pull-through anastomosis for low rectal cancer: a new method for preservation of anal function.

BACKGROUND: With recent improvements in surgical technique, oncological outcomes of low rectal cancer have improved over time. But the QoL impairment as a result of anal functional disorder cannot be ignored. And the incidence of anastomosis-related complications cannot be ignored. To address these problems, a personal technique for pull-through coloanal anastomosis (parachute-like intussuscept pull-through anastomosis) was introduced and evaluated. This technique can relatively reduce surgical complications, minimize the impact of anal function, and obviate a colostomy creation. METHODS: Between June 2020 and April 2021, 14 consecutive patients with rectal cancer underwent laparoscopic-assisted resection of rectal cancer in our hospital. Parachute-like pull-through anastomosis method was performed in all patients. Anal function, perioperative details, and postoperative outcomes were analyzed. RESULTS: The mean (SD) operative time of first stage was 282.1 min (range 220-370) with an average estimated blood loss of 90.3 mL (range 33-200). And the mean (SD) operative time of second was 46 min (range 25-76) with an average estimated blood loss of 16.1 mL (range 5-50). Wexner scores declined significantly during the median follow-up of 18 months. Four postoperative anastomosis-related complications occurred in 14 patients, including perianastomotic abscess: 1 case (7%), anastomotic stricture: 1 case (7%), and colonic ischemia of the exteriorized colonic segment: 2 cases (14%). CONCLUSION: The results suggest that the method can facilitate safe and easy completion of coloanal anastomosis, using parachute-like pull-through anastomosis, with acceptable anal function.

Lactiplantibacillus plantarum BW2013 protects mucosal integrity and modulates gut microbiota of mice with colitis.

This study explored the effects of Lactiplantibacillus plantarum (previously Lactobacillus plantarum) BW2013 on mucosal integrity and gut microbiota of mice with dextran sulfate sodium (DSS)-induced colitis. The results show that the clinical symptoms in DSS-modelled ulcerative colitis (UC) were improved by L. plantarum BW2013 via decreasing disease activity index scores and suppressing inflammatory cell infiltration. Furthermore, L. plantarum BW2013 decreased the levels of diamine oxidase activity, myeloperoxidase, and D-lactic acid. The mRNA expression of ZO-1, occludin, and claudin-1 was upregulated by L. plantarum BW2013, which also increased IL-10 and reduced TNF-α, IL-1ß, and IL-6 in the colon. 16S rDNA sequencing showed that L. plantarum BW2013 enhanced α-diversity. L. plantarum BW2013 upregulated significantly the abundance of unidentfied Lachnospiraceae, Lactococcus, Rikenella, Lactobacillus, and Odoribacter, which had an inhibitory effect on inflammation and a protective effect on the integrity of the mucosa. These results demonstrate that L. plantarum BW2013 alleviates DSS-modelled UC by protecting mucosal integrity and ameliorating the composition of gut microbiota.

Two unusual novel iridoid glycosides from Cornus officinalis fruit and their biological activities.

Two unusual novel iridoid glycosides, cornsecoside A (1) and cornsecoside B (2), were isolated from a 40% ethanol elution fraction of a 50% ethanol extract of Cornus officinalis fruit. Their structures were determined by spectroscopic data analysis combined with hydrolysis and ECD spectroscopy. In addition, compounds 1 and 2 exhibited cytotoxic activity against Bel-7402 cells with IC50 values of 8.12 and 9.31 µM, and were neuroprotective against H2O2-induced SH-SY5Y cell injure at a concentration of 10 µM.

Unveiling the Differences in Biological Properties of Dental Pulp Stem Cells from Normal and Inflamed Pulp: A Comprehensive Comparative Study.

BACKGROUND The aims of the study were to comprehensively compare the morphology, immunophenotype, proliferation, migration, and regeneration potential of normal dental pulp stem cells (DPSCs) versus inflammatory dental pulp stem cells (iDPSCs). MATERIAL AND METHODS Healthy pulp or inflamed pulp tissue was used to isolate and culture DPSCs and iDPSCs, respectively. These cell populations were characterized by flow cytometry, colony formation assay, transwell assay, and multi-directional differentiation in vitro. RESULTS No difference was observed in the morphology, cell-surface markers, or cell migration between DPSCs and iDPSCs. DPSCs showed a higher colony-forming capacity, proliferative viability, and osteo/dentinogenesis ability compared with iDPSCs. However, iDPSCs demonstrated enhanced neurogenesis, angiogenesis, adipogenesis, and chondrogenesis capacities in comparison to DPSCs. CONCLUSIONS Our data revealed the differences of biological properties between DPSCs and iDPSCs. The highly angiogenic and neurogenic potential of iDPSCs indicate their possible use in the regeneration of the dentin-pulp complex and support the critical role of angiogenesis and neurogenesis in pulp regeneration.

Dicer1 Promotes Colon Cancer Cell Invasion and Migration Through Modulation of tRF-20-MEJB5Y13 Expression Under Hypoxia.

Hypoxia plays a key role in colorectal cancer (CRC) metastasis, but its underlying mechanism remains largely unknown. Dicer1, an RNase, has been considered as a tumor regulator in many tumors. However, whether Dicer1 affects CRC progression under hypoxia remains uncertain. In this study, we found that Dicer1 expression was induced by hypoxia in CRC cells and it mediates hypoxia-induced CRC cell progression. Furthermore, we found that the expression of tRF-20-MEJB5Y13, a small non-coding RNA derived from tRNA, was increased under hypoxic conditions, and its upregulation by Dicer1 resulted in hypoxia-induced CRC cell invasion and migration. These results advance the current understanding of the role of Dicer1 in regulating hypoxia signals and provide a new pathway for the development of therapeutic interventions for inhibiting cancer progression.

TRF-20-M0NK5Y93 suppresses the metastasis of colon cancer cells by impairing the epithelial-to-mesenchymal transition through targeting Claudin-1.

tRNA-derived fragments (tRFs) are derived from corresponding tRNAs and have been shown by several studies to be novel biological markers for tumour diagnosis and therapy. However, until now, the effects of tRFs on the progression of colorectal cancer (CRC) and especially on the epithelial-to-mesenchymal transition (EMT) have remained unknown. Our study aimed to assess CRC-related tRFs and examine the effects of key tRFs on CRC progression and related mechanisms. After hypoxic treatment, tRF sequencing and real-time PCR assays were performed to identify key tRFs. Then, functional tests were designed to verify the effects and evaluate the mechanism after cell transfection under normoxic conditions. A total of 14 tRFs were differentially expressed in the hypoxia and control groups. Based on the results of PCR assay verification and conditional selection, tRF-20-M0NK5Y93 could be a promising target for exploration, as its expression was significantly lower under hypoxic conditions than under control conditions. tRF-20-M0NK5Y93 inhibited CRC cell migration and invasion partly by targeting Claudin-1, an EMT-related molecule. The results of the present study suggest that tRF-20-M0NK5Y93 promotes CRC cell migration and invasion partly by regulating Claudin-1 during EMT.

Four new monacolin analogs from Monascus purpureus-fermented rice.

Four new monacolin analogs, monacolin T (1), monacolin U (2) 6a-O-methyl-4,6-dihydromonacolin L (3), and 6a-O-ethyl-4,6-dihydromonacolin L (4) were isolated from the ethanolic extract of Monascus purpureus-fermented rice. Their structures were determined by a combination of 1D, 2D NMR experiments (1H-1HCOSY, HSQC, HMBC, and ROESY), and mass spectrometry. In vitro cytotoxic assay, all compounds were inactive at the concentration of 10 µM.

Four new taraxastane-type triterpenoic acids from Cirsium setosum.

Four new taraxastane-type triterpenoids acids 3ß,22α-dihydroxy-20-taraxasten-30-oic acid (1), 3ß-hydroxy-22-oxo-20-taraxasten-30-oic acid (2), 3-oxo-22α-hydroxy-20- taraxasten-30-oic acid (3), and 3ß,19ß-dihydroxy-20-taraxasten-30-oic acid (4) were isolated and characterized from Cirsium setosum (Willd.) MB. Their structures were determined by the combination of 1D and 2D NMR experiments ((1)H-(1)HCOSY, HSQC, HMBC and ROESY) and mass spectrometry. Compound 2 exhibited potent selective cytotoxicity against human ovarian cancer cell line A2780 with an IC50 value of 3.9 µM.

Structure elucidation and NMR assignments of an unusual aromatic monacolin analog from Monascus purpureus-fermented rice.

One unusual aromatic monacolin analog, aromonacolin A (1), was isolated from the ethanolic extract of Monascus purpureus-fermented rice. Its structure was elucidated by extensive spectroscopic (HRESIMS, (1)H NMR, (13)C NMR, HSQC, HMBC, and NOESY) and chemical methods. The absolute configuration of the C-6 secondary alcohol was deduced via the circular dichroism data of the in situ formed [Rh(2)(OCOCF(3))(4)] complex.

Structure elucidation and complete NMR spectral assignment of an unusual aromatic monacolin analog from Monascus purpureus-fermented rice.

One unusual aromatic monacolin analog, monacophenyl, was isolated from the ethanolic extract of Monascus purpureus-fermented rice. Its structure was completely and unambiguously assigned by one- and two-dimensional NMR techniques ((1)H NMR, (13)C NMR, HSQC, HMBC and NOESY) and high-resolution ESI-MS spectrometry.

[Study on supercritical CO2 extraction of flavonoids from Cynomorium songaricum].

OBJECTIVE: To study the extraction technology of flavonoids from Cynomorium songaricum by supercritical CO2 extraction. METHODS: The effects of pressure, temperature, time, concentration of alcohol, dosage of chemical preparation, flux of CO2 and particle size were studied by single factor analysis and orthogonal test. RESULTS: The optimized conditions were as follows: particle size 60 - 80 sieve mesh, the pressure was 30 MPa, the temperature was 50 degrees C, the time was 75 min, concentration of alcohol was 50%, entrainment rate was 8%, flux of CO2 was 5 mL/min. The total flavonoids yield could reach 21.18% under the above conditions. CONCLUSION: This method is simple, rapid and higher extraction yield, so it is suitable for the extraction of flavonoids from Cynomorium songaricum.