Search

This study focused on the role of methionine (MET) in the autophagy of gastric cancer stem cells (GCSCs) and aims to elaborate its regulatory mechanism. In the present study, the GCSCs were isolated from human gastric cancer cell lines using an anti-CD44 antibody, and then cultured in MET+ homocysteine (HCY)− or MET−HCY+ medium. In MET+HCY–treated GCSCs, autophagy was suppressed, the methylation and phosphorylation of RAB37 were elevated, and miR-200b expression was down-regulated. Lentiviral vector (LV-) carrying methionine-γ lyase (an enzyme that could specifically lyse MET; Metase) promoted autophagy, reduced the methylation and phosphorylation of RAB37, and up-regulated miR-200b expression in MET+HCY–-treated GCSCs. Then, we found that miR-200b suppressed the expression of protein kinase C α (PKCα), a protein that could inactivate RAB37 through promoting its phosphorylation. LV-Metase down-regulated RAB37 phosphorylation via miR-200b/PKCα, thus promoting the RAB37-mediated autophagy and suppressing cell viability in MET+HCY–treated GCSCs. Finally, the in vivo study proved that LV-Metase treatment inhibited tumor growth through up-regulating RAB37 expression. In conclusion, MET suppressed RAB37 expression via enhancing its methylation and suppressed RAB37 activity via miR-200b/PKCα axis, thus repressing RAB37-mediated autophagy in GCSCs. The supplementation of Metase lysed MET, thus inducing the autophagy of GCSCs and inhibiting tumor growth. [ABSTRACT FROM AUTHOR]

The intraoperatively rotational control of femoral shaft fractures treated with a closed intramedullary interlocking nailing is a challenging problem. A novel surgical technique that includes respective insertions of guidewires into the proximal and distal femur under the guidance of a 2-dimensional fluoroscopy-based navigation system and the measurements of the intersection angle subtended by the proximal and distal guidewires with the smartphone positional software has been designed to provide intraoperatively quantitative parameters of femoral rotation deformation. The comparison of these parameters with preoperative measurement values of the contralateral intact femur on computed tomography images was used to align the proximal and distal femur fragments based on periaxial rotation. The purpose of this study was to evaluate its clinical suitability. Ten adult patients with femoral shaft fractures were attempted to correct intraoperatively femoral rotational deformity using this novel technique. The additional operation time was 20.04 ± 3.27 minutes. The angle of femoral anteversion was 20.85° ± 4.22°, 38.14° ± 19.07°, and 22.77° ± 3.38° in the contralateral intact and preoperatively and postoperatively injured femur, respectively. The mean absolute difference between both limbs was preoperatively 21.55° ± 10.14° with a statistically significant difference ( P = .005) and postoperatively 3.24° ± 1.69° with no statistically significant difference ( P = .092). Our results showed this novel technique could become an effective tool to correct intraoperatively rotational malalignment of femoral fractures. [ABSTRACT FROM AUTHOR]

Two new isoaurones derivatives were obtained from Callistephus chinensis flower. Their structures were elucidated on the basis of extensive spectroscopic analyses. Both of the new compounds were evaluated cytotoxic activity. Phytochemical investigation of Callistephus chinensis flower led to the isolation of two new isoaurones derivatives (Z)-4′,4,10-trihydroxy-siamaurone (1) and (E)-4′,4,10-trihydroxy-siamaurone (2). The structures of these new compounds were identified by the interpretation of spectroscopic data (mainly 1D and 2D NMR) and by comparison with data reported in the literature. Both of the new compounds were evaluated for their cytotoxicity. [ABSTRACT FROM AUTHOR]

Two novel noroleanane saponins, tubeimoside A ( 1) and tubeimoside B ( 2), and a new dammarane triterpene saponin, tubeimoside C ( 3), together with two known compounds, 4 and 5, were isolated from the bulbs of Bolbostemma paniculatum ( Maxim.) Franquet. Compound 4 was found in this genus for the first time. Based on spectroscopic methods, including IR, NMR (DEPT, COSY, HMQC, HMBC, and TOCSY), and MS experiments, and chemical reactions, the structures of the new compounds were elucidated as 3 β-[ β- D-glucopyranosyl-(1→2)- β- D-glucopyranosyloxy]-2 β,23-dihydroxy-28-norolean-12-en-16-one ( 1), 3 β-[ β- D-glucopyranosyl-(1→2)- β- D-glucopyranosyloxy]-2 β,23-dihydroxy-28-norolean-12-en-22-one ( 2), (3 β,7 β)-7,18,20-trihydroxydammar-24-en-3-yl 2- O- α- L-arabinopyranosyl- β- D-glucopyranoside ( 3). [ABSTRACT FROM AUTHOR]

A new dammarane-type triterpene saponin was isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino. Its structural elucidation was accomplished mainly on the basis of the interpretation of spectroscopic data, such as IR, HR–TOF–MS and NMR. Its cytotoxic activity was evaluated against one human cancer cell line HL-60 using MTT assay. [ABSTRACT FROM PUBLISHER]

Four new dammarane-type triterpene saponins, 1-4, were isolated from the aerial parts of Gynostemma pentaphyllum (Thunb.) Makino. Their structural elucidations were accomplished mainly on the basis of spectroscopic methods, such as IR, HR-TOF-MS, and NMR. Compounds 1-4 showed moderate cytotoxic activities against cancer cell lines HL-60, Colon205, and Du145 in vitro. [ABSTRACT FROM AUTHOR]

From the dried petals of Carthamus tinctorius, a new flavonoid, (2R)-4',5-dihydroxyl-6,7-di-O-β-d-glucopyranosyl flavanone (1) and a new aromatic glucoside, methyl-3-(4-O-β-d-glucopyranosylphenyl) propionate (4) were isolated along with four known compounds (2S)-4',5-dihydroxyl-6,7-di-O-β-d-glucopyranosyl flavanone (2), 6-hydroxykaempferol-3,6-di-O-β-d-glucopyranoside (3), 4-O-β-d-glucosyl-trans-p-coumaric acid (5), and 4-O-β-d-glucosyl-cis-p-coumaric acid (6). Their structures were identified on the basis of chemical and spectroscopic methods. [ABSTRACT FROM AUTHOR]

A new bufadienolide named 16β-acetoxy-bufarenogin (1), together with six known bufadienolides, namely, 11α,12β-dihydroxy-bufalin (2), bufotalin (3), hellebrigenin (4), desacetylbufotalin (5), gamabufotalin (6), and resibufagin (7) were isolated from Chan'Su. Of these, 2 was a new natural product. Their structures were elucidated by spectral methods. The cytotoxic activities in vitro of these compounds have been assayed against HeLa cell line. They all showed strong cytotoxic activities. [ABSTRACT FROM AUTHOR]

A new phenolic glycoside, sinapic acid 4-O-β-d-(6'-sinapoyl)glucopyranoside (1) and a new sucrose ester, 6,6'-di-O-sinapoylsurcose (3), were isolated from the roots of Cynanchum amplexicaule (Sieb. et Zucc.), along with two known compounds, 6-O-[E]-sinapoyl-d-glucopyranoside (2) and sibricose A1 (4). Their structures were elucidated on the basis of both chemical and spectroscopic methods. [ABSTRACT FROM AUTHOR]

The antibacterial activities of compounds (I) and (II) are evaluated, and (I) is shown to exhibit moderate activity. [ABSTRACT FROM AUTHOR]

Isolation and structure determination of five novel triterpenes, gypensapogenins H (Ia), I (Ib), L (II), J (III), and K (IV) are reported. [ABSTRACT FROM AUTHOR]

isolation and structure determination of two novel noroleanane saponins, tubeimoside A (I) and regioisomeric tubeisomide B, and a new dammarane triterpene saponin, tubeimoside C (II), together with two known compounds [ABSTRACT FROM AUTHOR]

Abstract: A new lignan (7R,8S,8′R)-4,4′,9-trihydroxy-7,9′-epoxy-8,8′-lignan, and three new phenolics, carayensin-A, carayensin-B, and carayensin-C, together with 13 known compounds were isolated from the shells of Carya cathayensis. Their chemical structures were established mainly by 1D and 2D NMR techniques and mass spectrometry. All the compounds were evaluated for cytotoxicity against several human tumor types including human colorectal cancer cell lines (HCT-116, HT-29), human lung cancer cell line (A549), and human breast cancer cell line (MCF-7). The compounds 1, 5, 6, and 16 are considered to be potential as antitumor agents, which could significantly inhibit the cancer cell growth in a dose-dependent manner. [Copyright &y& Elsevier]

Background: The small intestine is known to play a crucial role in the development and remission of diabetes mellitus (DM). However, the exact mechanism by which mid-small intestinal bypass improves glucose metabolism in diabetic rats is not fully understood., Aim: To elucidate the mechanisms by which mid-small intestinal bypass improves glucose metabolism., Methods: Streptozotocin (STZ) was used to induce DM in Sprague-Dawley (SD) rats at a dose of 60 mg/kg. The rats were then randomly divided into two groups: The mid-small intestine bypass (MSIB) group and the sham group (underwent switch laparotomy). Following a 6-wk recovery period post-surgery, the rats underwent various assessments, including metabolic parameter testing, analysis of liver glycogen levels, measurement of key gluconeogenic enzyme activity, characterization of the gut microbiota composition, evaluation of hormone levels, determination of bile acid concentrations, and assessment of the expression of the intestinal receptors Takeda G protein-coupled receptor 5 and farnesoid X receptor., Results: The MSIB group of rats demonstrated improved glucose metabolism and lipid metabolism, along with increased hepatic glycogen content. Furthermore, there was a decrease in the expression of the key gluconeogenic enzymes phosphoenolpyruvate carboxykinase 1 and glucose-6-phosphatase. Importantly, the MSIB group exhibited a substantial increase in the abundances of intestinal Lactobacillus , Clostridium symbiosum , Ruminococcus gnavus , and Bilophila . Moreover, higher levels of secondary bile acids, such as intestinal lithocholic acid, were observed in this group. Remarkably, the changes in the gut microbiota showed a significant correlation with the expression of key gluconeogenic enzymes and glucagon-like peptide 1 (GLP-1) at 6 wk postoperatively, highlighting their potential role in glucose regulation. These findings highlight the beneficial effects of mid-small intestine bypass on glucose metabolism and the associated modulation of the gut microbiota., Conclusion: The findings of this study demonstrate that the introduction of postoperative intestinal Clostridium symbiosum in the mid-small intestine contributes to the enhancement of glucose metabolism in nonobese diabetic rats. This improvement is attributed to the increased inhibition of hepatic gluconeogenesis mediated by GLP-1, resulting in a favorable modulation of glucose homeostasis., Competing Interests: Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: Different metabolic/bariatric surgery approaches vary in their effect on weight loss and glucose levels, although the underlying mechanism is unclear. Studies have demonstrated that the gut microbiota might be an important mechanism of improved metabolism after metabolic/bariatric surgery., Aim: To investigate the relationship between the improvement in metabolic disturbances and the changes in gut microbiota after gastric or intestinal bypass., Methods: We performed sleeve gastrectomy (SG), distal small intestine bypass (DSIB) or sham surgery in nonobese rats with diabetes induced by 60 mg/kg streptozotocin (STZ-DM)., Results: The group comparisons revealed that both SG and DSIB induced a reduction in body weight and significant improvements in glucose and lipid metabolism in the STZ-DM rats. Furthermore, DSIB exhibited a stronger glucose-lowering and lipid-reducing effect on STZ-DM rats than SG. 16S ribosomal RNA gene sequencing revealed the gut abundance of some Lactobacillus spp. increased in both the SG and DSIB groups after surgery. However, the DSIB group exhibited a more pronounced increase in the gut abundance of Lactobacillus spp. compared to the SG group, with more Lactobacillus spp. types increased in the gut., Conclusion: The gut abundance of Lactobacillus was significantly correlated with the improvement in glycolipid metabolism and the change in serum fibroblast growth factor 21 levels., Competing Interests: Conflict-of-interest statement: All authors declare that there are no potential conflicts of interest., (©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.)

A pair of enantiomeric triketone-phloroglucinol hybrids, (+)- and (-)-myrtuspirone A (1), featuring an unprecedented 3-isopropyl-3 H-spiro[benzofuran-2,1'-cyclohexane] backbone, were isolated from the leaves of Myrtus communis. The absolute configuration of each enantiomer of 1 was determined by X-ray diffraction and chemical calculations. Furthermore, the gram-scale total syntheses of (±)-1 and (-)-1 were conducted in four steps using a Michael- N-iodosuccinimide (NIS)-mediated (3 + 2)-annulation reaction. Both (+)- and (-)-1 exhibited antibacterial activities against Gram-positive bacteria including multidrug-resistant strains.

Callisretones A (1) and B (2), two rearranged phloroglucinol-monoterpenoid adducts featuring an unprecedented isopropylcyclopenta[b]benzofuran backbone, together with their postulated biosynthetic precursors (3-9), were isolated from Callistemon rigidus. The previously assigned absolute configurations of viminalins H (7), L (8), and N (9) were revised and unequivocally established by X-ray diffraction data. A putative biosynthetic pathway toward callisretones A and B involving the rearrangement of the terpenoid motif is proposed. In addition, 1 and 2 showed inhibitory effects on nitric oxide production with IC 50 values of 15.3 ± 1.0 and 17.7 ± 1.1 μM, respectively.

Background : Stem cells isolated from peripheral blood of gastric adenocarcinoma patients have noninvasive advantages. However, at present, there is no simple and effective separation technique. Purpose : In this study, CD133+ cells were isolated from peripheral blood of patients with gastric adenocarcinoma by using specific immunomagnetic particles, and the immunology of subcultured cells was identified to evaluate whether the immune magnetic particle separation had any effect on the cells themselves. Methods : Immune magnetic particles, made by a specific technique, are used to sort out the cells whose membrane could express CD133 from peripheral blood of gastric adenocarcinoma patients. By observing the sorted cells within serum-free culturing, we compare the differences in morphology and proliferation ability between the collected cells and cells from a standard tumor cell line. At the same time, an immunofluorescence method is used to detect the expression of the CD133 antibody. Moreover, this study explores the inhibition effect on gastric adenocarcinoma stem cell growth when combining 5-fluorouracil and methionine enzymes. Results and Conclusions : The specific immunomagnetic particles have a small diameter and strong sorting characteristics. In the experiment, there were 20 patients with gastric adenocarcinoma. CD133+ cells were separated successfully from peripheral blood of 13 patients (65%), among which subcultured cells of 9 cases (69.2%) were found to express CD44+ antigens. The sorted cells grew vigorously with a variety of morphologies in non-inducing culture, while the cells induced by β transforming growth factor presented slow growth and uniform morphology. There was a significant difference ( P < 0.05) in cell proliferation between these two groups and the standard tumor cell line. In addition, 5-fluorouracil combined with methionine enzyme inhibited the growth of gastric adenocarcinoma stem cells significantly ( P < 0.05). Accordingly, the CD133+/CD44+ cells from peripheral blood of gastric adenocarcinoma patients, sorted by specific immune magnetic particles, had clear stem cell properties as determined by cell function and structure. This lays a foundation for gastric adenocarcinoma stem cell extraction, culture and further research on stem cell characteristics.