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1.
Chem Biol Interact ; 364: 110058, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35872048

ABSTRACT

Efficient endosomal escape after cellular uptake is a major challenge for the clinical application of therapeutic proteins. To overcome this obstacle, several strategies have been used to help protein drugs escape from endosomes without affecting the integrity of the cell membrane. Among them, some triterpenoid saponins with special structures were used to greatly enhance the anti-tumor therapeutic effect of protein toxins. Herein, we demonstrated that platycodin D (PD), polygalacin D (PGD) and platycodin D2 (PD2) from Platycodonis Radix significantly enhanced the ability of MHBP (a type I ribosome-inactivating protein toxin MAP30 fused with a cell-penetrating peptide HBP) to induce apoptosis in hepatoma cells. Based on the results of co-localization of endocytosed EGFP-HBP with a lysosomal probe and Galectin-9 vesicle membrane damage sensor, we demonstrated that PD, PGD and PD2 have the ability to promote endosomal escape of endocytic proteins without affecting the integrity of the plasma membrane. Meanwhile, we observed that cholesterol metabolism plays an important role in the activity of PD by RNA-seq analysis and KEGG pathway enrichment analysis, and confirm that PD, PGD and PD2 enhance the anti-tumor activity of MHBP by inducing the redistribution of free cholesterol and inhibiting the activity of cathepsin B and cathepsin D. Finally, we found that PD synergized with MHBP to induce caspase-dependent apoptosis through inhibiting Akt and ERK1/2 signaling pathways and activating JNK and p38 MAPK signaling pathways. This study provides new insights into the application of PD in cancer therapy and provides efficient and promising strategies for the cytosolic delivery of therapeutic proteins.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Saponins , Triterpenes , Apoptosis , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Endosomes/metabolism , Endosomes/pathology , Humans , Liver Neoplasms/metabolism , MAP Kinase Signaling System , Proto-Oncogene Proteins c-akt/metabolism , Ribosomal Proteins/metabolism , Saponins/chemistry , Signal Transduction , Triterpenes/chemistry
2.
Mol Ther Nucleic Acids ; 20: 345-358, 2020 Jun 05.
Article in English | MEDLINE | ID: mdl-32199130

ABSTRACT

Osteoporosis is characterized by the reduction of bone mineral density and deterioration of bone quality which leads to high risk of fractures. Some microRNAs (miRNAs) have been confirmed as potential modulators of osteoblast differentiation to maintain bone mass maintenance. We aimed to clarify whether miR-122 could regulate osteoblast differentiation in ovariectomized rats with osteoporosis. miR-122 was upregulated and Purkinje cell protein 4 (PCP4) was downregulated in ovariectomized rats. PCP4 was identified as a target of miR-122 by dual-luciferase reporter gene assay. We transfected isolated osteoblasts from ovariectomized rats with miR-122 mimic or inhibitor or PCP4 overexpression vectors. Proliferation and differentiation of osteoblasts were repressed by the overexpression of miR-122 but enhanced by overexpression of PCP4. miR-122 could induce the activation of the c-Jun NH2-terminal kinase (JNK) signaling pathway, while PCP4 blocked this pathway. Rescue experiments further demonstrated that the inhibiting effects of miR-122 on osteoblast differentiation could be compensated by activation of the PCP4 or inhibition of JNK signaling pathway. Collectively, our data imply that miR-122 inhibits osteoblast proliferation and differentiation in rats with osteoporosis, highlighting a novel therapeutic target for osteoporotic patients.

3.
Chin J Traumatol ; 19(5): 278-282, 2016 Oct 01.
Article in English | MEDLINE | ID: mdl-27780508

ABSTRACT

PURPOSE: Tibial pilon fractures remain challenging for an orthopaedic surgeon to repair. External fixation (ExFix) and open reduction and internal fixation (ORIF) are two widely used methods for repairing tibial pilon fractures. However, conclusions of comparative studies regarding which method is superior are controversial. Our aim is to compare ORIF and ExFix and clarify which method is better in terms of reduction and union results and major complications. METHODS: A computerized research of MEDLINE, EMBASE, Springer, and Cochrane Library (before December 2014) for studies of any design comparing ORIF and ExFix was conducted. Weighted mean difference (WMD), risk ratio (RR) and corresponding 95% confidence intervals (CI) were used for esti- mating the effects of the two methods. Statistical analyses were done using Review Manager Version 5.2. RESULTS: Ten cohort studies and one randomized clinical trial were included in our ultimate analysis. And the analysis found no significant difference between the two methods in deep infection (p = 0.13), reduction (p = 0.11), clinical evaluation (p = 0.82), post-traumatic arthrosis (p = 0.87), and union time (p = 0.35). Besides, ExFix group was found to have a higher rate of superficial infection (p =0.001), malunion (p = 0.01) and nonunion (p = 0.02), but have a lower risk of unplanned hardware removal (p = 0.0002). CONCLUSIONS: We suggest that ORIF has a relatively lower incidence rate of superficial infection, malunion and nonunion, but a higher rate of unplanned hardware removal. No difference was found in deep infection, reduction, clinical evaluation, post-traumatic arthrosis and union time.


Subject(s)
External Fixators , Fracture Fixation, Internal/methods , Tibial Fractures/surgery , External Fixators/adverse effects , Fracture Fixation, Internal/adverse effects , Humans
4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-286845

ABSTRACT

<p><b>OBJECTIVE</b>To compare agitated saline solution (AS) and the mixture of AS with blood (ASb) as the contrast agents in contrast transcranial Doppler (c-TCD) in the diagnosis of patent foramen ovale (PFO).</p><p><b>METHODS</b>We recruited 248 consecutive patients for c-TCD examination between November 2015 and January 2016, and the sequence of the use of AS (9 mL saline solution mixed with 1 mL air) and ASb (9 mL saline solution and a drop of the patient's blood mixed with 1 mL air) was determined by coin-tossing method. Before the examination, the contrast agent was injected with or without Valsalva maneuvers (VM), and the number of microbubbles within 25 s after the contrast agent injection and the time of first appearance of microbubbles were recorded by observing the TCD spectrum. Each injection was repeated twice and the interval between tests was at least 5 min. We classified PFO according to the number of microbubbles into negative (no microbubble), grade I (1-10 microbubbles), grade II (>10 microbubbles but no curtain), and grade III (with curtain).</p><p><b>RESULTS</b>s The positivity rates in diagnosis with AS without VM, AS with VM, ASb without VM, and ASb with VM tests were 10.9%, 23.8%, 12.1% and 25.8%, respectively. AS with VM test had a higher positive rate than AS without VM test (23.8% vs 10.9%, P=0.001), and ASb with VM test had a higher positive rate than ASb without VM test (25.8% vs 12.1%, P=0.001). The positive rates were similar between ASb without VM and AS without VM test (12.1% vs 10.9%, P=0.250) and between ASb with VM test and AS with VM test (25.8% vs 23.8%, P=0.125).</p><p><b>CONCLUSION</b>VM can improve the positive rate of PFO diagnosis in c-TCD examination, and the positive rates are comparable between examinations using the contrast agents AS and ASb.</p>


Subject(s)
Contrast Media , Chemistry , Foramen Ovale, Patent , Diagnostic Imaging , Microbubbles , Sensitivity and Specificity , Sodium Chloride , Ultrasonography, Doppler, Transcranial , Valsalva Maneuver
5.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-273725

ABSTRACT

<p><b>OBJECTIVE</b>To explore the effect of recombinant human erythropoietin (rhEPO) on expression of brain-derived neurotrophic factor (BDNF) in different brain regions of aging rats.</p><p><b>METHODS</b>Forty male SD rats were randomized equally into negative control group, D-galactose group, EPO treatment group, and positive control group. Rat models of subacute aging were established by continuous subcutaneous injection of 5% D-galactose. Immunohistochemical staining was used to analyze the variation of BDNF expressions in different brain regions of the aging rats with different treatments.</p><p><b>RESULTS</b>Significant brain region-specific differences in BDNF expression were found among the rats in different groups. Compared with those in the negative control group, the numbers of BDNF-positive cells in the hippocampal CA1 region, CA3 region, dentate gyrus (DG) and frontal cortex were all decreased obviously in D-galactose group (P<0.05) but increased in both EPO group and the positive control group (P<0.05) without significant differences between the latter two groups. In the rats in the same group, the number of BDNF-positive cells varied markedly in different brain regions (P<0.05), and the expression level of BDNF was the highest in the frontal cortex followed by the hippocampal CA3 region and the dentate gyrus, and was the lowest in the hippocampal CA1 region.</p><p><b>CONCLUSION</b>Treatment with rhEPO enhances the expression of BDNF in rat neural cells, suggesting that rhEPO may protect the nervous system from aging by regulating the BDNF pathway.</p>


Subject(s)
Animals , Humans , Male , Rats , Aging , Brain-Derived Neurotrophic Factor , Metabolism , CA1 Region, Hippocampal , Metabolism , CA3 Region, Hippocampal , Metabolism , Dentate Gyrus , Metabolism , Erythropoietin , Pharmacology , Frontal Lobe , Metabolism , Galactose , Neurons , Metabolism , Random Allocation , Rats, Sprague-Dawley , Recombinant Proteins , Pharmacology
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