Mechanism of total flavonoids of Rhododendra simsii in alleviating ischemic brain injury / 中国中药杂志

This study explores the effect of total flavonoids of Rhododendra simsii(TFR) on middle cerebral artery occlusion(MCAO)-induced cerebral injury in rats and oxygen-glucose deprivation/reoxygenation(OGD/R) injury in PC12 cells and the underlying mechanism. The MCAO method was used to induce focal ischemic cerebral injury in rats. Male SD rats were randomized into sham group, model group, and TFR group. After MCAO, TFR(60 mg·kg~(-1)) was administered for 3 days. The content of tumor necrosis factor-α(TNF-α), interleukin-1(IL-1), and interleukin-6(IL-6) in serum was detected by enzyme-linked immunosorbent assay(ELISA). The pathological changes of brain tissue and cerebral infarction were observed based on hematoxylin and eosin(HE) staining and 2,3,5-triphenyltetrazolium chloride(TTC) staining. RT-qPCR and Western blot were used to detect the mRNA and protein levels of calcium release-activated calcium channel modulator 1(ORAI1), stromal interaction molecule 1(STIM1), stromal intera-ction molecule 2(STIM2), protein kinase B(PKB), and cysteinyl aspartate specific proteinase 3(caspase-3) in brain tissues. The OGD/R method was employed to induce injury in PC12 cells. Cells were randomized into the normal group, model group, gene silencing group, TFR(30 μg·mL~(-1)) group, and TFR(30 μg·mL~(-1))+gene overexpression plasmid group. Intracellular Ca~(2+) concentration and apoptosis rate of PC12 cells were measured by laser scanning confocal microscopy and flow cytometry. The effect of STIM-ORAI-regulated store-operated calcium entry(SOCE) pathway on TFR was explored based on gene silencing and gene overexpression techniques. The results showed that TFR significantly alleviated the histopathological damage of brains in MCAO rats after 3 days of admini-stration, reduced the contents of TNF-α, IL-1, and IL-6 in the serum, down-regulated the expression of ORAI1, STIM1, STIM2, and caspase-3 genes, and up-regulated the expression of PKB gene in brain tissues of MCAO rats. TFR significantly decreased OGD/R induced Ca~(2+) overload and apoptosis in PC12 cells. However, it induced TFR-like effect by ORAI1, STIM1 and STIM2 genes silencing. However, overexpression of these genes significantly blocked the effect of TFR in reducing Ca~(2+) overload and apoptosis in PC12 cells. In summary, in the early stage of focal cerebral ischemia-reperfusion injury and OGD/R-induced injury in PC12 cells TFR attenuates ischemic brain injury by inhibiting the STIM-ORAI-regulated SOCE pathway and reducing Ca~(2+) overload and inflammatory factor expression, and apoptosis.

Molecular mechanism of ligustilide attenuating OGD/R injury in PC12 cells by inhibiting ferroptosis / 中国中药杂志

The aim of this study is to explore the mechanism of ligustilide, the main active constituent of essential oils of traditional Chinese medicine Angelicae Sinensis Radix, on alleviating oxygen-glucose deprivation/reperfusion(OGD/R) injury in PC12 cells from the perspective of ferroptosis. OGD/R was induced in vitro, and 12 h after ligustilide addition during reperfusion, cell viability was detected by cell counting kit-8(CCK-8) assay. DCFH-DA staining was used to detect the level of intracellular reactive oxygen species(ROS). Western blot was employed to detect the expression of ferroptosis-related proteins, glutathione peroxidase 4(GPX4), transferrin receptor 1(TFR1), and solute carrier family 7 member 11(SLC7A11), and ferritinophagy-related proteins, nuclear receptor coactivator 4(NCOA4), ferritin heavy chain 1(FTH1), and microtubule-associated protein 1 light chain 3(LC3). The fluorescence intensity of LC3 protein was analyzed by immunofluorescence staining. The content of glutathione(GSH), malondialdehyde(MDA), and Fe was detected by chemiluminescent immunoassay. The effect of ligustilide on ferroptosis was observed by overexpression of NCOA4 gene. The results showed that ligustilide increased the viability of PC12 cells damaged by OGD/R, inhibited the release of ROS, reduced the content of Fe and MDA and the expression of TFR1, NCOA4, and LC3, and improved the content of GSH and the expression of GPX4, SLC7A11, and FTH1 compared with OGD/R group. After overexpression of the key protein NCOA4 in ferritinophagy, the inhibitory effect of ligustilide on ferroptosis was partially reversed, indicating that ligustilide may alleviate OGD/R injury of PC12 cells by blocking ferritinophagy and then inhibiting ferroptosis. The mechanism by which ligustilide reduced OGD/R injury in PC12 cells is that it suppressed the ferroptosis involved in ferritinophagy.

Interferon-regulatory factors regulate macrophage polarization and its role in diseases / 药学学报

Macrophages are highly plastic and heterogeneous. In different types of inflammatory diseases, or at different stages of the same disease, macrophages can undergo phenotypic transformation to elicit different functions. Hence, exploring new regulatory mechanism of macrophage polarization and seeking for new key mediators will lay the foundation for the diagnosis and treatment of macrophage-related diseases, such as inflammatory diseases, autoimmune diseases, and cancer. Interferon regulatory factors (IRFs) have been reported to play an important role in the maturation and differentiation of macrophages. In this review, we will describe the structure and modulation pattern of IRFs, and then further summarize the molecular mechanism and signal regulation network of IRFs in pathological processes of related diseases through controlling macrophage polarization. Our review will explore the new therapeutic strategy and potential drug targets for related diseases.

Study on potential mechanism of hyperoside on improving ischemia/reperfusion injury based on network pharmacology / 中国药理学与毒理学杂志

OBJECTIVE To predict the potential targets of hyperoside (Hyp) on improving ischemia/reperfusion injury by network pharmacology, and explore its possible mechanism combined with related literature. METHODS The action targets of Hyp and ischemia/reperfusion injury were obtained by TCMSP, Swiss Target Prediction, Pharm Mapper, Simi?larity ensemble approach, Online Mendelian Inheritance in Man, DisGENT and database. The common targets of drugs and diseases were screened by Omishare and STRING database respectively, and the protein-protein interaction (PPI) network map was constructed. Then the interaction network between Hyp and disease targets was constructed by Cyto?scape software and topological cross-linking analysis was carried out. Then the interaction network between Hyp and disease targets was constructed and cross-linked analysis was carried out by using Cytoscape software. The gene ontol?ogy (GO) of the core target was analyzed by David database, and then the related pathways of the core target were enriched by KEGG database. RESULTS A total of 54 GO enrichment processes were obtained by GO enrichment anal?ysis of 44 common genes, including 38 biological processes (BP), 15 cell composition (CC) processes, and 1 molecular functional (MF) process. 43 items were obtained by signal pathway enrichment analysis in KEGG database. CONCLU?SION It is suggested that the mechanism of Hyp may be related to PI3K-Akt, RAP1, RAS, VEGF and other signal trans?duction pathways. The above results laid a theoretical foundation for the study of the mechanism and clinical application of the treatment of ischemia/reperfusion injury.

Effects of total flavonoids of Rhododendra simsii on ameliorating brain injury via G protein-coupled SOCE pathway mediated by STIM and Orai in subacute phase of ischemia/reperfusion / 中国药理学与毒理学杂志

OBJECTIVE To explore the effect of total flavonoids of Rhododendra simsii (TFR) on improving cerebral ischemia/reperfusion injury (CIRI) and its relationship with STIM/Orai-regulated operational Ca2+influx (SOCE) pathway. METHODS Oxygen-glucose deprivation/reoxygenation (OGD/R) PC12 cells were used to simulate CIRI in vitro, and the intracellular Ca2+ concentration and apoptosis rate of PC12 cells were detected by laser confocal microscope and flow cytometry, respectively. The regulation of STIM/Orai on SOCE was analyzed by STIM/Orai gene silencing and STIM/Orai gene overexpression. The CIRI model was established by MCAO in SD rats. The activities of inflammatory cyto?kines IL-1, IL-6 and TNF-αin serum were detected by ELISA. The pathological changes of ischemic brain tissue and the infarction of rat brain tissue were detected by HE staining and TTC staining. The protein and mRNA expression levels of STIM1, STIM2, Orai1, caspase-3 and PKB in brain tissue were detected by Western blotting and RT-qPCR, respectively. RESULTS The results of in vitro experiment showed that the fluorescence intensity of Ca2+ and apoptosis rate in PC12 cells treated with TFR were significantly lower than those in OGD/R group, and this trend was enhanced by SOCE antagonist 2-APB. STIM1/STIM2/Orai1 gene silencing significantly reduced apoptosis and Ca2+overload in OGD/R model, while TFR combined with overexpression of STIM1/STIM2/Orai1 aggravated apoptosis and Ca2+overload. In the in vivo experiment, TFR significantly reduced the brain histopathological damage, infarction of brain tissue, the contents of IL-1, IL-6 and TNF-α in the serum in MCAO rats and down-regulated the expression of STIM1, STIM2, Orai1 and caspase-3 protein and mRNA in the brain tissue, and up-regulated the expression of PKB. The above effects were enhanced by the addition of 2-APB. CONCLUSION The above results indicate that TFR may reduce the contents of inflammatory factors and apoptosis, decrease Ca2+ overload and ameliorate brain injury by inhibiting SOCE pathway mediated by STIM and Orai, suggesting that it has a protective effect against subacute CIRI.

Chloroquine induces apoptosis of human hepatocellular carcinoma cells in vitro by miR-26b-mediated regulation of Mcl-1 / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of chloroquine in inducing apoptosis of human hepatocellular carcinoma cells and explore the possible mechanism.</p><p><b>METHODS</b>MTT assay and flow cytometry were used to evaluate chloroquine-induced growth inhibition and apoptosis in human hepatocellular carcinoma HepG2 cells, respectively. The ATP levels in chloroquine-treated cells were detected using an ATP assay kit. PCR and Western blotting were used to detect the expression levels of miR-26b and Mcl-1 in the cells, respectively.</p><p><b>RESULTS</b>Chloroquine inhibited the proliferation of HepG2 cells in a time- and concentration-dependent manner. Treatments with 80 µmol/L chloroquine for 24, 48, and 72 h induced survival rates of (71.59∓0.2)%, (45.40∓0.5)%, and (26.34∓1.4)% in the cells. Treatments with chloroquine at 40, 80, and 160 µmol/L for 5 h resulted in obviously lowered intracellular ATP levels in the cells to 87.80%, 71.29%, and 38.02% of the control level, respectively. At 80 µmol/L, chloroquine significantly increased the expression of miR-26b and down-regulated the expression of Mcl-1 in HepG2 cells, and the application of the miR-26b inhibitor increased the cellular expression of Mcl-1.</p><p><b>CONCLUSION</b>s Chloroquine can inhibit the cell proliferation, reduce ATP level and induce apoptosis in HepG2 cells possibly through miR-26b-mediated regulation of Mcl-1.</p>

Monocarboxylate transporter 1 enhances the sensitivity of breast cancer cells to 3-bromopyruvate in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the role of monocarboxylate transporter 1 (MCT1) in enhancing the sensitivity of breast cancer cells to 3-bromopyruvate (3-BrPA).</p><p><b>METHODS</b>The inhibitory effect of 3-BrPA on the proliferation of breast cancer cells was assessed with MTT assay, and brominated propidium bromide single staining flow cytometry was used for detecting the cell apoptosis. An ELISA kit was used to detect the intracellular levels of hexokinase II, lactate dehydrogenase, lactate, and adenosine triphosphate, and Western blotting was performed to detect the expression of MCT1. MDA-MB-231 cells were transiently transfected with MCT1 cDNA for over-expressing MCT1, and the effect of 3-BrPA on the cell proliferation and adenosine triphosphate level was deteced.</p><p><b>RESULTS</b>3-BrPA did not produce significant effects on the proliferation and apoptosis of MDA-MB-231 cells, and the cells treated with 200 µmol/L 3-BrPA for 24 h showed an inhibition rate and an apoptosis rate of only 8.72% and 7.8%, respectively. The same treatment, however, produced an inhibition rate and an apoptosis rate of 84.6% and 82.3% in MCF-7 cells, respectively. In MDA-MB-231 cells with MCT1 overexpression, 200 µmol/L 3-BrPA resulted in an inhibition rate of 72.44%, significantly higher than that in the control cells (P<0.05); treatment of the cells with 25, 50, 100, and 200 µmol/L 3-BrPA for 6 h resulted in intracellular adenosine triphosphate levels of 96.98%, 88.44%, 43.3% and 27.56% relative to the control level respectively.</p><p><b>CONCLUSION</b>MCT1 can enhance the sensitivity of breast cancer cells to 3-BrPA possibly by transporting 3-BrPA into cells to inhibit cell glycolysis.</p>

Impact factors on results of semi-quantitative western blot in pharmacological research / 中国药学杂志

OBJECTIVE: To investigate the impact factors of the semi-quantitative Western blot (WB), offering a guidance on research of pharmacological effects of drugs at the level of proteins. METHODS: Total proteins were extracted from the Huh7.5 cells infected with hepatitis C virus and quantified with BCA kit, HCV Core protein was chose as target protein, and protein Tubulin or Gap-dh, which was encoded by housekeeping gene, as the internal control. By controlling the experimental factors, such as loading sample amount, concentration and the incubation time of first antibodies, and dilutions of chemiluminescent fluid as well, we analyzed those factors how to impact the semi-quantitative results. RESULTS: The semi-quantitative results showed that there is a linear relationship between relative intensity of target protein and the amount of total protein at must protein concentration range, beyond which, the range-ability of relative intensity of target protein reduced, even no changes. However, sample volume loaded, or protein selected as internal reference has little influence on the result of semi-quantitative WB. In the context of obtaining high-quality band, concentration and incubation time of antibodies or dilution of chemiluminescent fluid also has no influence on it. Yet, the semi-quantitative WB has certain defects and our results show that the permissible error of semi-quantitative result should be controlled within 15%. CONCLUSION: The key impact factor on the result of semi-quantitative WB is the target protein amount of loading. On the premise of obtaining clear and high-quality bands, appropriately selecting loading volume of samples, concentration and incubation time of first antibodies, and dilutions of chemiluminescent fluid is conducive to accomplish experiments without affecting the final results of semi-quantitative WB.

2-DG enhances TRAIL-induced apoptosis of leukemia HL-60 cells / 中国实验血液学杂志

This study was purposed to investigate the effects of 2-deoxy-D-glucose (2-DG) on sensitizing HL-60 cells to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis and its possible mechanism. The proliferative inhibition of HL-60 cells treated with different concentrations of 2-DG and TRAIL was measured by MTT assay. The cells were treated with 2-DG, TRAIL, and 2-DG combined with TRAIL at the concentration < IC50 value, i.e. 10 mmol/L for 2-DG and 100 ng/ml for TRAIL. Apoptosis was analyzed by flow cytometry with PI staining; the expression of RIP1, GRP78, and PARP was analyzed by Western blot; the activity of caspase-3 was detected by special detection kit. The results showed that the combined treatment of HL-60 cells for 48 h induced an apoptotic rate of (45.1 ± 4.3)%, which was significantly higher than that of treated with 2-DG or TRAIL alone; at the same time, the combined treatment potentiated the expression of GRP78 and caspase-3 activity, and down-regulated the expression of RIP1. It is concluded that 2-DG can sensitize HL-60 cells to TRAIL-induced apoptosis, which may be correlated with excessive endoplasmic reticulum stress response, down-regulation of RIP1, and increase of caspase-3 activity.

Effects of cisplatin combined with heparanase inhibitor on proliferation and invasion of human nasopharyngeal carcinoma cells / 药学学报

This study is to investigate the effects of cisplatin combined with heparanase inhibitor OGT2115 on proliferation, invasion and migration of human nasopharyngeal carcinoma cells CNE-2 and to provide a new target for the treatment of metastasis of nasopharyngeal carcinoma. MTT assay was used to detect the cell viability of CNE-2 after exposure to different concentrations of DDP (2, 4, 8, 16 and 32 micromol x L(-1)), different concentrations of OGT2115 (0.4, 0.8, 1.6, 3.2 and 6.4 micromol x L(-1)), and DDP combined with OGT2115. Transwell assay was applied to analyze the effects of drugs on invasion and migration of human nasopharyngeal carcinoma cells. Wound healing assay was performed to detect cell migration and heparanase activity was analyzed by ELISA. MTT results showed that DDP can inhibit the proliferation of CNE-2 cells in a time and concentration-dependent manner, with an IC50 of 24.03 micromol x L(-1) at 24 h (P < 0.05), low concentration of DDP has almost no inhibitory effect on cell invasion and migration. DDP combined with OGT2115 can significantly inhibit cell invasion and migration. Inhibition of heparanase can significantly enhance anti-invasion and anti-proliferation of DDP.