Glutamate Chemical Exchange Saturation Transfer (GluCEST) MRI to Evaluate the Rapid Antidepressant Effects of Ketamine in the Hippocampus of Rat Depression Model

BACKGROUND

Ketamine is a quick acting antidepressant drug, and an accurate detection method is lacking. Ketamine's effects in a rat depression model have not previously been well explored using glutamate chemical exchange saturation transfer (GluCEST).

PURPOSE

To investigate the GluCEST changes of chronic unpredictable mild stress (CUMS) rats after receiving either ketamine or saline injection.

STUDY TYPE

Randomized animal model trial.

ANIMAL MODEL

12 CUMS and 6 Sprague-Dawley rats. Divided into three groups: ketamine (N = 6), saline (N = 6), and control (N = 6).

FIELD STRENGTH/SEQUENCE

7.0 T/the sequence is GluCEST and 1 H MR spectroscopy (MRS).

ASSESSMENT

The CUMS rats were exposed to different stress factors for 8 weeks. The glutamate concentration in the hippocampus was assessed by the GluCEST,1 H MRS, and the high-performance liquid chromatography (HPLC).

STATISTICAL TESTS

The t-test, Mann-Whitney U test, and Pearson's correlation.

RESULTS

In depression conditions, GluCEST signals were lower in the bilateral hippocampus than in control group. Thirty minutes after ketamine injection, the GluCEST signals in the bilateral hippocampus were higher compared with the saline group (left: 2.99 ± 0.34 [Control] vs. 2.44 ± 0.20 [Saline] vs. 2.85 ± 0.11 [Ketamine]; right: 2.97 ± 0.28 [Control] vs. 2.49 ± 0.25 [Saline] vs. 2.86 ± 0.19 [Ketamine]). In 1 H MRS, significant changes were only observed in the left hippocampus (2.00 ± 0.16 [Control] vs. 1.81 ± 0.09 [Saline] vs. 2.04 ± 0.14 [Ketamine]). Furthermore, HPLC results showed similar trends to those observed in the GluCEST results (left: 2.32 ± 0.22 [Control] vs. 1.96 ± 0.11 [Saline] vs. 2.18 ± 0.11 [Ketamine]; right: 2.35 ± 0.18 [Control] vs. 1.87 ± 0.16 [Saline] vs. 2.09 ± 0.08 [Ketamine]).

DATA CONCLUSION

GluCEST can sensitively evaluate the ketamine's antidepressant effects by detecting the fast increase in glutamate concentration.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 1.

Vitamin D3 promotes gastric cancer cell autophagy by mediating p53/AMPK/mTOR signaling

Objective: Vitamin D3 has the general properties of a lipid-soluble vitamin, but is also an active steroid hormone that can regulate the proliferation, apoptosis and differentiation of many tumor cells, and exerts anticancer activity against numerous malignancies. However, the mechanism underlying the effects of vitamin D3 on tumors is not fully understood. Here, we used network pharmacology and in vitro experimental approaches to explore the mechanism of vitamin D3 activity in the context of gastric cancer. Methods: The Targetnet, SuperPred, SwissTargetPrediction, and PharmMapper databases were screened for potential drug-related targets, while we used data from the PharmGKB, Drugbank, OMIM, DisGeNET, CTD, and GeneCards databases to identify potential targets associated with gastric cancer. Disease-drug crossover genes were obtained by constructing Venn diagrams. Gene ontology and Kyoto Encyclopedia of Genomes (KEGG) enrichment analyses of crossover genes were conducted and STRING was used to generate protein interaction networks and identify core targets. CCK-8 experiments were performed and apoptosis detected to assess the effect of vitamin D3 on gastric cancer cells. Western blotting was applied to detect p53/AMPK/mTOR signaling, as well as autophagy-, cell cycle-, and apoptosis-related proteins. Results: A total of 485 targets of vitamin D3 activity were obtained and 1200 gastric cancer disease-related targets discovered. Further, 60 potential targets for vitamin D3 in gastric cancer treatment were identified. KEGG analysis indicated that potential targets were mainly involved in the cell cycle, HIF-1 signaling, and the AMPK pathway, among other pathways. These findings were validated using cellular experiments, which demonstrated that the viability of AGS and SGC-7901 cells was impeded by vitamin D3. Further, vitamin D3 promoted apoptosis and inhibited the cell cycle in those cell lines, as well as activating the p53/AMPK/mTOR pathway, which promotes autophagy and inhibits tumor development. Conclusion: Our network pharmacological analyses provide preliminarily data supporting a role for vitamin D3 in promoting autophagy and apoptosis in gastric cancer cells, and in activating the p53/AMPK/mTOR pathway, which inhibits gastric cancer cell proliferation. Our findings demonstrate the molecular mechanism underlying the effect of vitamin D3 in cure of gastric cancer.

Exploring the mechanism of aloe-emodin in the treatment of liver cancer through network pharmacology and cell experiments

Objective: Aloe-emodin (AE) is an anthraquinone compound extracted from the rhizome of the natural plant rhubarb. Initially, it was shown that AE exerts an anti-inflammatory effect. Further studies revealed its antitumor activity against various types of cancer. However, the mechanisms underlying these properties remain unclear. Based on network pharmacology and molecular docking, this study investigated the molecular mechanism of AE in the treatment of hepatocellular carcinoma (HCC), and evaluated its therapeutic effect through in vitro experiments. Methods: CTD, Pharmmapper, SuperPred and TargetNet were the databases to obtain potential drug-related targets. DisGenet, GeneCards, OMIM and TTD were used to identify potential disease-related targets. Intersection genes for drugs and diseases were obtained through the Venn diagram. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of intersecting genes were conducted by the website of Bioinformatics. Intersection genes were introduced into STRING to construct a protein-protein interaction network, while the Cytoscape3.9.1 software was used to visualize and analyze the core targets. AutoDock4.2.6 was utilized to achieve molecular docking between drug and core targets. In vitro experiments investigated the therapeutic effects and related mechanisms of AE. Results: 63 overlapped genes were obtained and GO analysis generated 3,646 entries by these 63 intersecting genes. KEGG analysis mainly involved apoptosis, proteoglycans in cancer, TNF signaling pathway, TP53 signaling pathway, PI3K-AKT signaling pathway, etc. AKT1, EGFR, ESR1, TP53, and SRC have been identified as core targets because the binding energies of them between aloe-emodin were less than -5 kcal/Mol.The mRNA and protein expression, prognosis, mutation status, and immune infiltration related to core targets were further revealed. The involvement of AKT1 and EGFR, as well as the key target of the PI3K-AKT signaling pathway, indicated the importance of this signaling pathway in the treatment of HCC using AE. The results of the Cell Counting Kit-8 assay and flow analysis demonstrated the therapeutic effect of AE. The downregulation of EGFR, PI3KR1, AKT1, and BCL2 in mRNA expression and PI3KR1, AKT,p-AKT in protein expression confirmed our hypothesis. Conclusion: Based on network pharmacology and molecular docking, our study initially showed that AE exerted a therapeutic effect on HCC by modulating multiple signaling pathways. Various analyses confirmed the antiproliferative activity and pro-apoptotic effect of AE on HCC through the PI3K-AKT signaling pathway. This study revealed the therapeutic mechanism of AE in the treatment of HCC through a novel approach, providing a theoretical basis for the clinical application of AE.

The mechanism of vitamin D3 in preventing colorectal cancer through network pharmacology

Objective: Colorectal cancer (CRC) is a common cancer that cannot be detected at an early stage and is a major challenge in oncology research. Studies have shown that vitamin D3 has some anti-cancer and preventive effects on colorectal cancer, but the exact anti-cancer mechanism is not clear. We applied the relevant research methods of network pharmacology to speculate and validate the possible potential pharmacological mechanisms of vitamin D3 for the prevention of colorectal cancer, and to provide more theoretical support for the clinical anticancer effects of vitamin D3. Methods: The relevant targets for vitamin D3 and CRC were obtained from the database of drug and disease targets, respectively. The target of vitamin D3 and the target of colorectal cancer were taken to intersect to obtain common targets. Then, the PPI network was constructed. In addition, the pathways of drug-disease interactions were predicted by GO and KEGG enrichment analysis. Finally, the obtained results were verified to ensure the reliability of the experiments. Results: 51 targets of vitamin D3 for the prevention of colorectal cancer were obtained. The 10 core targets were obtained from the PPI network. The 10 core targets include: ALB, SRC, MMP9, PPARG, HSP90AA1, IGF1, EGFR, MAPK1, MAP2K1 and IGF1R. The core targets were further validated by molecular docking and animal experiments. The results suggest that vitamin D3 plays a key role in the prevention of CRC through core targets, PI3K-Akt pathway, HIF-1 pathway, and FoxO pathway. Conclusion: This study will provide more theoretical support for vitamin D3 to reduce the incidence of CRC and is important to explore more pharmacological effects of vitamin D3.

Exploring the mechanism of curcumin in the treatment of colon cancer based on network pharmacology and molecular docking

Objective: Curcumin is a plant polyphenol extracted from the Chinese herb turmeric. It was found that curcumin has good anti-cancer properties in a variety of cancers, but the exact mechanism is not clear. Based on the network pharmacology and molecular docking to deeply investigate the molecular mechanism of curcumin for the treatment of colon cancer, it provides a new research direction for the treatment of colon cancer. Methods: Curcumin-related targets were collected using PharmMapper, SwissTargetPrediction, Targetnet and SuperPred. Colon cancer related targets were obtained using OMIM, DisGeNET, GeneCards and GEO databases. Drug-disease intersection targets were obtained via Venny 2.1.0. GO and KEGG enrichment analysis of drug-disease common targets were performed using DAVID. Construct PPI network graphs of intersecting targets using STRING database as well as Cytoscape 3.9.0 and filter core targets. Molecular docking via AutoDockTools 1.5.7. The core targets were further analyzed by GEPIA, HPA, cBioPortal and TIMER databases. Results: A total of 73 potential targets of curcumin for the treatment of colon cancer were obtained. GO function enrichment analysis yielded 256 entries, including BP(Biological Progress):166, CC(celluar component):36 and MF(Molecular Function):54. The KEGG pathway enrichment analysis yielded 34 signaling pathways, mainly involved in Metabolic pathways, Nucleotide metabolism, Nitrogen metabolism, Drug metabolism - other enzymes, Pathways in cancer,PI3K-Akt signaling pathway, etc. CDK2, HSP90AA1, AURKB, CCNA2, TYMS, CHEK1, AURKA, DNMT1, TOP2A, and TK1 were identified as core targets by Cytoscape 3.9.0. Molecular docking results showed that the binding energies of curcumin to the core targets were all less than 0 kJ-mol-1, suggesting that curcumin binds spontaneously to the core targets. These results were further validated in terms of mRNA expression levels, protein expression levels and immune infiltration. Conclusion: Based on network pharmacology and molecular docking initially revealed that curcumin exerts its therapeutic effects on colon cancer with multi-target, multi-pathway. Curcumin may exert anticancer effects by binding to core targets. Curcumin may interfere with colon cancer cell proliferation and apoptosis by regulating signal transduction pathways such as PI3K-Akt signaling pathway,IL-17 signaling pathway, Cell cycle. This will deepen and enrich our understanding of the potential mechanism of curcumin against colon cancer and provide a theoretical basis for subsequent studies.

Glutamate Chemical Exchange Saturation Transfer Imaging and Functional Alterations of Hippocampus in Rat Depression Model: A Pilot Study

BACKGROUND

Adjusting abnormal glutamate neurotransmission is a crucial mechanism in the treatment of depression. However, few non-invasive techniques could effectively detect changes in glutamate neurotransmitters, and no consensus exists on whether glutamate could affect resting-state function changes in depression.

PURPOSE

To study the changes in glutamate chemical exchange saturation transfer (GluCEST) value in the hippocampus of rat model exposed to chronic unpredictable mild stress (CUMS), and to explore the effect of this change on the activity of hippocampal glutamatergic neurons.

STUDY TYPE

Prospective animal study.

ANIMAL MODEL

Twenty male Sprague-Dawley rats (200-300 g).

FIELD STRENGTH/SEQUENCE

7.0 T scanner. Fat rapid acquisition relaxation enhancement sequence for GluCEST, and echo planner imaging sequence for resting-state functional magnetic resonance imaging (rs_fMRI).

ASSESSMENT

Rats were divided into two groups: CUMS group (N = 10) and control group (CTRL, N = 10). The magnetization transfer ratio asymmetry analysis was used to quantify the GluCEST data, and evaluate the rs_fMRI data through the amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) analysis.

STATISTICAL TESTS

A t-test was used to compare the difference in GluCEST or rs_fMRI between CUMS and CTRL groups. Spearman's correlation was applied to explore the correlation between GluCEST values and abnormal fMRI values in hippocampus. Statistical significance was set at P < 0.05.

RESULTS

The GluCEST value in the left hippocampus has changed significantly (3.3 ± 0.3 [CUMS] vs. 3.9 ± 0.4 [CTRL], P < 0.05). In addition, the GluCEST value was significantly positively correlated with the ALFF values (r = 0.5, P < 0. 05, df = 7) and negatively correlated with the ReHo values (r = -0.6, P < 0.05, df = 7).

DATA CONCLUSION

GluCEST technique has the feasibility of mapping glutamate changes in rat depression. Glutamate neurotransmitters are important factors affecting the abnormal function of neural activity.

LEVEL OF EVIDENCE

2 TECHNICAL EFFICACY: Stage 1.

Optical properties of D and S defects induced by Si+/Ni+ ions co-implanting into Si films on insulator

In the article, we report the photoluminescence (PL) properties of D and S defects induced by Si⁺/Ni⁺ ions co-implanting into the top Si film of the silicon-on-insulator (SOI) wafer. Variable-temperature PL spectra of these co-implanted SOI samples indicate that the light emitting from the D defects can be observed as high as 273 K. In comparison with the other ion-implantation, the Si⁺/Ni⁺ ion-co-implantation optimizes luminescent temperature stability of the both D and S defects and purifies the S defect type in silicon then effectively restrains the spectral broadening of the S-line in PL spectra. The depth distribution of the D and S defects along the normal direction of SOI surface at the corresponding ion-implantation energy has been well depicted by detecting the PL signals of the layer-by-layer etched SOI surface, respectively. These results provide valuable information to fabricate SOI-based infrared light sources for optical fiber communications.

[Production and identification of anti-paraoxon monoclonal antibodies]

Paraoxon (E600) was conjugated to bovine serum albumin(BSA) or tachypleus tridentatus hemocyanin (TTH) by diazotization. Two hybridoma cell lines secreting monoclonal antibodies(McAb) against paraoxon have been established by fusing mouse myeloma cells and splenocytes from Balb/c mice immunized with E600-BSA. The chromosomes of the hybridoma cell 2B10 were analyzed. The immunoglobulin of the McAb was classified. The affinity and specificity of this antibody were determined. The hybridoma cells have fairly reserved the antibody-producing capacity after continuously growing or stored in liquid nitrogen for 10 weeks.

[Injury to urinary system in the operation of gynecology]

OBJECTIVE

To reduce the incidence of urinary system injury from gynecology operations.

METHODS

26 cases with urinary system injuries during gynecological operations were analyzed from 1982 to 1996.

RESULTS

The incidence of urinary injury in this hospital was 0.34%, and injuries occurred most frequently in the bladder. Among the 17 cases of bladder injuries, 12 occurred during tubal ligation, 3 during cesarean section, and 2 in myomectomy. There were 9 cases of ureter injuries, 6 cases occurred in radical hysterectomy for cervical cancer, 1 in cesarean section with hysterectomy, and 2 in hysterectomy with broad ligament leiomyoma.

CONCLUSIONS

This study demonstrated that it was important to be familiar with the regional anatomy, to operate strictly and separate those organs carefully in preventing the urinary system injury.

[A comparison between diltiazem SR and diltiazem HCL in the treatment of angina pectoris]

This study included 168 patients with angina pectoris, who were divided into two groups, the diltiazem SR (No. 88) group and diltiazem HCL (No. 80) group. The two groups were comparable in age and duration of coronary heart disease. The results were as follows: (1) The total clinical effect of diltiazem SR (94.3%) was slightly greater than that of diltiazem HCL (82.5%), the effect in ECG improvement was 53.3% and 53.4% respectively. (2) The rate of adverse effect was 12.5% in diltiazem SR group and 14.4% in diltiazem HCL group. It is concluded that the two different types of diltiazem have similar effect in the treatment of angina pectoris. However, it is more convenient to take diltiazem SR than diltiazem HCL as the former needs only twice a day.