Role and mechanism of PKCs in midazolam-induced relaxation of aortic smooth muscle in spontaneously hypertensive rats / 中国药理学通报

Aim To investigate the effect of protein kinase C (PKCs) on midazolam-induced relaxation of aortic smooth muscle in spontaneously hypertensive rats (SHR) and the underlying mechanism. Methods U-sing the isolated vessel tension measurement system, the relaxant effect of midazolam on aortic smooth muscle of SHR and Wistar-Kyoto (WKY) rats was observed. After preincubation with GF109203X (GF, a broad-spectrum inhibitor of PKCs), LY333531 (LY, PKCp2 specific inhibitor) and PKC6 pseudo-substrate inhibitor (PPS), the changes of midazolam-induced relaxation amplitude were observed. Western blot was used to detect the effect of midazolam on the phosphorylation level of PKC [32 in SHR aortic smooth muscle. The effect of midazolam, LY, GF and PPS on the phosphorylation level of the key proteins (CPI-17/ MYPT1/MLC) in calcium sensitization pathway in SHR aortic smooth muscle was also examined. Results Midazolam concentration-dependently relaxed aortic smooth muscle in SHR and WKY. GF significantly inhibited midazolam-induced relaxation amplitude of SHR and WKY aortic smooth muscle. LY and PPS had no significant effect on midazolam-induced relaxation amplitude of WKY aortic smooth muscle. In contrast, LY markedly inhibited midazolam-induced relaxation amplitude of SHR aortic smooth muscle. Midazolam significantly inhibited the phosphorylation level of PKC [32 enhanced by NE in SHR aortic smooth muscle. Midazolam, LY and GF all evidently inhibited the phosphorylation level of the key proteins in calcium sensitization pathway enhanced by NE in SHR aortic smooth muscle. Conclusions Midazolam induces excessive relaxation of SHR aortic smooth muscle by inhibiting calcium sensitization pathway mediated by PKC [32.

Regulation of platelet function by cantharidin via PI3K/Akt/PKC pathway / 中国药理学通报

To investigate the effect of cantharidin ( CTD) on platelet function and the mechanism of anti-platelet aggregation. Methods Washed platelets were collected from the venous blood of healthy volunteers. The effect of CTD on platelet aggregation and release was determined by aggregometer. The CTD concentration was 2.5 ,5 ,10 μmol • L

Antidepressant-like effect of caffeic acid: Involvement of the cellular signaling pathways

Abstract Caffeic acid is a phenolic compound widely distributed in plants and beverages such as coffee. Although its mechanism of action is poorly understood, caffeic acid reportedly induces antidepressant-like and neuroprotective effects. This study aimed to investigate the involvement of cellular signaling pathways in acute antidepressant-like effect induced by caffeic acid in mice. All procedures were approved by the Institutional Animal Ethics Committee of the UNIVALI n. 021/2013. Female Swiss mice were administered with vehicle, caffeic acid (5 mg/ kg, p.o.), inhibitor (H-89, U0126, chelerythrine, or PD9859, i.c.v.) or caffeic acid plus inhibitor. The behavioral effects were evaluated 1h after the administration of compounds to mice using tail suspension test (TST) and open field test (OFT). The results showed that the antidepressant- like effect of caffeic acid in mice was possibly mediated by the activation of PKA, MEK 1/2, PKC and MAPK (as assessed using TST), without compromising their locomotor activity (as assessed using OFT). Our results demonstrated, at least in part, the pathways involved in the neuroprotective and behavioral effects of caffeic acid.

Roles of c-Fos, EGR-1, PKA, and PKC in cognitive dysfunction in rats after propofol anesthesia

Abstract This study aimed to investigate possible changes in the spatial memory of rats and the expression or activity of EGR-1, c-Fos, PKA, and PKC after propofol anesthesia. Thirty-six Sprague-Dawley rats aged 20 months and 36 Sprague-Dawley rats aged three months were each randomly divided into three groups: the control group, the Morris Water Maze (MWM) group, and the propofol group. In the propofol groups of both young and aged rats, the rats were anesthetized by propofol for two or four hours and then performed the MWM test two days or two weeks after anesthesia to assess cognitive function. EGR-1, c-Fos, PKA, and PKC expressions in the rat hippocampus were determined via immunohistochemistry. For the older rats, the escape latency in the P4h/2d group was significantly prolonged (P < 0.05), and the learning curve was right-shifted in the P4h/2w group (P < 0.05). The expression levels of EGR-1, c-Fos, PKA, and PKC in the MWM groups were significantly higher than those in the control groups (P < 0.05). In the P4h/2d group of aged rats, the expression levels of both PKA and PKC were decreased compared with those of the MWM groups. The decreased expression of both protein kinases may be responsible for the observed impairment after propofol anesthesia

Protein Kinase C Controls the Excitability of Cortical Pyramidal Neurons by Regulating Kv2.2 Channel Activity / 神经科学通报·英文版

The family of voltage-gated potassium Kv2 channels consists of the Kv2.1 and Kv2.2 subtypes. Kv2.1 is constitutively highly phosphorylated in neurons and its function relies on its phosphorylation state. Whether the function of Kv2.2 is also dependent on its phosphorylation state remains unknown. Here, we investigated whether Kv2.2 channels can be phosphorylated by protein kinase C (PKC) and examined the effects of PKC-induced phosphorylation on their activity and function. Activation of PKC inhibited Kv2.2 currents and altered their steady-state activation in HEK293 cells. Point mutations and specific antibodies against phosphorylated S481 or S488 demonstrated the importance of these residues for the PKC-dependent modulation of Kv2.2. In layer II pyramidal neurons in cortical slices, activation of PKC similarly regulated native Kv2.2 channels and simultaneously reduced the frequency of action potentials. In conclusion, this study provides the first evidence to our knowledge that PKC-induced phosphorylation of the Kv2.2 channel controls the excitability of cortical pyramidal neurons.

Mechanism of citizene improving insulin resistance of HepG2 cells based on KDSR gene / 中国药理学通报

Aim To explore whether Huaqizeren, an experienced prescription for the treatment of IR, could improve IR by interfering with KDSR expressionfrom the perspective of KDSR gene. Methods The KDSR gene was overexpressed in normal HepG2 cells, and the IR cell model was established at the same time. The expression level of KDSR was detected by QRT PCR and Western blot; the content of ceramide was detected by HPLC-MS; the expression level of KDSR was detected by Western blot. The phosphorylation level of PKC£/Akt/Fox01 was detected by Western blot, and the glucose content was detected by GOD-POD assay before and after administration. Results After administration, the expression level of KDSR and ceramide in IR cells and KDSR overexpression cells significantly decreased, and the abnormal expression of PKC£/Akt/ FoxOl signaling pathway was improved. Meanwhile, the glucose content in IR cells and KDSR overexpres-sion cells significantly decreased after administration, and the differences were statistically significant (P < 0. 01). Conclusions One of the mechanisms of Huaqizeren in improving IR may be down-regulating the expression of KDSR, decreasing the content of ceramide , and then regulating the expression of key proteins in PKC£/Akt/Fox01 signaling pathway, thus reducing the glucose content in cells and improving IR.

Use of protein kinase C and phospholipase A2 inhibitors in bovine endometrial cells treated with estradiol and calcium ionophore / Uso de inibidores de proteína quinase C e fosfolipase A2 em células endometriais bovinas tratadas com estradiol e ionóforo de cálcio

The release of endometrial prostaglandin-F2α (PGF2α) in bovine females can be induced in vivo by estradiol (E2). However, its role in this mechanism has not been clarified. We hypothesized that E2 stimulates the activity and abundance of protein kinase C (PKC) and phospholipase A2 (PLA2). Our objective in this study was to analyze the effects of PKC and PLA2 inhibitors on PGF2α synthesis induced by E2 and calcium ionophore (CI) in bovine endometrial cells (BEND cells; Experiment 1). Additionally, we evaluated the abundance of PKC and PLA2 in endometrial explants of cows treated or not with E2 17 days after estrus (D17, D0 = estrus; Experiment 2). In Experiment 1, BEND cells were submitted to a PKC inhibitor (10 µM of C25H24N4O2; bisindolylmaleimide I, or BIS I), a PLA2 inhibitor (20 µM of arachydoniltrifluoromethane or AACOCF3), or none. The BEND cells were subsequently treated with E2 and CI, and PGF2α concentrations were measured in the culture medium through radioimmunoassay. For DIF-12 (PGF2α concentration 12 h after treatment subtracted from PGF2α concentration at hour 0), no PKC inhibitor effect was observed (P= 0.2709). However, DIF-12 was lower (P < 0.05) for groups treated with the PLA2 inhibitor and PLA2 inhibitor + CI + E2 groups than the control and CI + E2 groups. Thus, AACOCF3 was an efficient PLA2 inhibitor in the BEND cells culture system, and E2 did not stimulate the synthesis of PKC and PLA2. In Experiment 2, cyclic Nellore heifers received none (n = 5) or 3 mg (n = 6) of 17ß-E2 on D17 and were slaughtered 2 h after administration. The abundance of PKC and PLA2 in the endometrial tissue was evaluated using Western blotting analysis. No E2 effect was observed on PKC (P = 0.08) and PLA2 (P = 0.56). We concluded that E2 did not stimulate the activity and abundance of PKC and PLA2.(AU)

A liberação endometrial de prostaglandina-F2α (PGF2α) em fêmeas bovinas pode ser induzida in vivo pelo estradiol (E2). Entretanto o seu mecanismo de ação ainda não foi bem esclarecido. Nossa hipótese é que o E2 estimula a atividade e a abundância da proteína quinase C (PKC) e da fosfolipase A2 (PLA2). Nosso objetivo com este estudo foi analizar os efeitos de inibidores de PKC e PLA2 na síntese de PGF2α induzida por E2 e ionóforo de cálcio (CI) em células endometriais bovinas (células BEND; Experimento 1). Adicionalmente, nós avaliamos a abundância de PKC e PLA2 em explantes endometriais de vacas tratadas com ou sem E2 17 dias após o estro (D17, D0 = estro; Experimento 2). No Experimento 1, células BEND foram submetidas ao inibidor de PKC (10 µM de C25H24N4O2; bisindolylmaleimide I, ou BIS I), e ao inibidor de PLA2 (20 µM de arachydoniltrifluoromethane ou AACOCF3) ou a nenhum inibidor. As células BEND foram subsequentemente tratadas com E2 e CI e concentrações de PGF2α foram mensuradas no meio de cultura por radioimunoenssaio. Para DIF-12 (concentração de PGF2α 12 horas depois do tratamento, subtraída da concentração de PGF2α na hora 0), não foi observado efeito do inibidor de PKC (P = 0.2709). Entretanto DIF-12 foi menor (P < 0.05) nos grupos tratados com inibidor de PLA2 e inibidor de PLA2 + CI + E2 quando comparados com o grupo controle e o grupo CI + E2. O AACOCF3 foi um eficiente inibidor de PLA2 em sistema de cultura de células BEND e o E2 não estimulou a síntese de PKC e PLA2. No Experimento 2, novilhas Nelore cíclicas receberam 3 mg de 17ß-E2 (n = 6) ou nenhum tratamento (n = 5) no D17 e foram abatidas duas horas depois da administração dos tratamentos. A quantidade de PKC and PLA2 no tecido endometrial foi avaliada pela técnica de Western Blotting. Não foi observado efeito do E2 sobre a PKC (P= 0.08) e nem sobre a PLA2 (P= 0.56). Conclui-se que o E2 não estimulou a atividade e abundância de PKC e PLA2.(AU)

Activated PKB/GSK-3β synergizes with PKC-δ signaling in attenuating myocardial ischemia/reperfusion injury via potentiation of NRF2 activity: Therapeutic efficacy of dihydrotanshinone-I

@#Disrupted redox status primarily contributes to myocardial ischemia/reperfusion injury (MIRI). NRF2, the endogenous antioxidant regulator, might provide therapeutic benefits. Dihydrotanshinone-I (DT) is an active component in Salvia miltiorrhiza with NRF2 induction potency. This study seeks to validate functional links between NRF2 and cardioprotection of DT and to investigate the molecular mechanism particularly emphasizing on NRF2 cytoplasmic/nuclear translocation. DT potently induced NRF2 nuclear accumulation, ameliorating post-reperfusion injuries via redox alterations. Abrogated cardioprotection in NRF2-deficient mice and cardiomyocytes strongly supports NRF2-dependent cardioprotection of DT. Mechanistically, DT phosphorylated NRF2 at Ser40, rendering its nuclear-import by dissociating from KEAP1 and inhibiting degradation. Importantly, we identified PKC-δ-(Thr505) phosphorylation as primary upstream event triggering NRF2-(Ser40) phosphorylation. Knockdown of PKC-δ dramatically retained NRF2 in cytoplasm, convincing its pivotal role in mediating NRF2 nuclear-import. NRF2 activity was further enhanced by activated PKB/GSK-3β signaling via nuclear-export signal blockage independent of PKC-δ activation. By demonstrating independent modulation of PKC-δ and PKB/GSK-3β/Fyn signaling, we highlight the ability of DT to exploit both nuclear import and export regulation of NRF2 in treating reperfusion injury harboring redox homeostasis alterations. Coactivation of PKC and PKB phenocopied cardioprotection of DT in vitro and in vivo, further supporting the potential applicability of this rationale. Graphical abstract

Effect and Mechanism of Midostaurin Derivatives 5'''-methoxyfradcarbazole A on Mouse Leukemia CB3 Cells / 中国药学杂志

OBJECTIVE: To investigate the mechanism of midostaurin derivative 5'''-methoxyfradcarbazole A of action in inhibiting mouse leukemia cells (CB3) growth. METHODS: MTT assay was employed to evaluate the effect of compound 5'''-methoxyfradcarbazole A on the proliferation of CB3 cells, and generate the growth inhibition curves. Flow cytometry and Annexin V-FITC /PI double staining were used to determine the changes of the cell cycle, cell differentiation and apoptosis. Western blot analysis was applied to test the effects of 5'''-methoxyfradcarbazole A on cyclin and apoptosis-related proteins. RESULTS: The compound 5'''-methoxyfradcarbazole A could significantly inhibit the growth of CB3 cells, and the half maximal inhibitory concentration (IC50) of the compound was (0.587±0.135)μmol•L-1. 5'''-Methoxyfradcarbazole A was able to induce early apoptosis and late apoptosis of CB3 cells in a time- and dose-dependent manner. At the same time, it also affected the cell cycle of CB3 and significantly increased the proportion of G2 phase. The expression of CD41, a platelet differentiation marker, and Ter119, an erythrocyte differentiation marker, were also increased in CB3 cells treated with 5'''-methoxyfradcarbazole A. Besides, the expressions of apoptosis-related proteins Bim, PARP1 and cyclin-related protein P21 were significantly increased, and the phosphorylated ERK protein was decreased. CONCLUSION: Midostaurin derivative 5'''-methoxyfradcarbazole A could increase the apoptosis of CB3 cells by promoting the expression of apoptotic protein Bim, and cause G2 phase arrest by increasing the expression of cyclin protein P21. Also, the changes of the expression levels of PARP1 and phosphorylated ERK protein also partly explain the inhibition of 5'''-methoxyfradcarbazole A on CB3 cells growth.

Effect of protein kinase C β inhibitor on renal ischemia-reperfusion injury and expression level of macrophage subtypes in rat models / 器官移植

Objective To investigate the effect of protein kinase C (PKC) β inhibitor on the renal ischemia-reperfusion injury (RIRI) in rat models and detect the expression level of macrophage subtypes. Methods Eighteen healthy SD male rats were randomly divided into the Sham operation group (Sham group, n=6), RIRI group (n=6), PKCβ inhibitor +RIRI group (Inhibitor+RIRI group, n=6). Serum and left renal tissue samples were collected at postoperative 24 h. The contents of serum creatinine (Scr) and blood urea nitrogen (BUN) were detected by automatic biochemical analyzer. The infiltration of inflammatory cells and pathological injury in the renal tissues were observed by hematoxylin-eosin (HE) staining. The expression levels of CD68, inducible nitric oxide synthase (iNOS) and CD206 proteins in the renal tissues of rats in each group were assessed by immunohistochemistry and Western blot. Results The contents of serum Scr and BUN in the RIRI group were significantly higher than those in the Sham group (both P < 0.05). The contents of serum Scr and BUN in the Inhibitor+RIRI group were considerably lower than those in the RIRI group (both P < 0.05). No obvious renal injury was noted in the Sham group, whereas renal inflammatory cell infiltration and renal tubular structural damage were observed in the RIRI group. The renal inflammatory cell infiltration and renal tubular structural damage in the Inhibitor+RIRI group was slighter than that in the RIRI group. The protein expression levels of CD68, iNOS and CD206 in the renal tissue of rats in the RIRI group were significantly higher than those in the Sham group (all P < 0.05). The protein expression levels of CD68 and iNOS in the Inhibitor+RIRI group were remarkably lower than those in the RIRI group (all P < 0.05). The expression level of CD206 protein in the Inhibitor+RIRI group was significantly higher than that in the RIRI group (P < 0.05). Conclusions PKC β inhibitor can alleviate the RIRI in rat models to certain extent, which may be correlated with the role of PKC β inhibitor in mitigating inflammatory cell infiltration in ischemic renal tissues and promoting the expression of alternatively activated macrophage

Mechanism of coronary artery constriction induced by 5-HT / 中国病理生理杂志

AIM:To investigate the possible mechanism of coronary artery contraction induced by 5-hydroxytryptamine(5-HT).METHODS:Isolated coronary artery rings were obtained from male Wistar rats,and the vas-cular tension meter was used to determine the tension of the coronary artery rings.The effects of inhibitors of different sig-naling pathway on vascular contraction tension induced by 5-HT were observed.RESULTS:Firstly,we found that 5-HT2A receptor antagonist sarpogrelate(1 μmol/L)completely eliminated the coronary artery contraction induced by 5-HT.Phos-pholipase Cβ(PLCβ)inhibitor U73122(10 μmol/L and 50 μmol/L), Rho-related protein kinase inhibitor Y-27632(3 μmol/L and 10 μmol/L)and protein kinase C δ subunit(PKCδ)inhibitor rottlerin(3 μmol/L and 10 μmol/L)signifi-cantly inhibited the contraction of coronary artery ring caused by 5-HT(P<0.05).In addition, compared with the un-treated group,vascular contraction tension induced by 5-HT was also decreased significantly by L-type calcium channel (Cav1.2)blocker nifedipine(1 μmol/L), store-operated Ca2+entry(SOCE)inhibitor SKF96365(10 μmol/L and 30 μmol/L)and 2-aminoethoxydiphenyl borate(2-APB,50 μmol/L and 100 μmol/L)(P<0.05).At the same time,5-HT also induced vasoconstriction after treated with nifedipine(1 μmol/L)Kerbs-Henseleit(K-H)liquid without calcium (P<0.05).CONCLUSION:5-HT activates 5-HT2Areceptor induced coronary artery contraction,possibly related to the PKC/Rho kinase signaling pathway and calcium regulation.

The functions of P2X3 receptor in inflammatory pain and it's influencial factors / 医学研究生学报

Inflammatory Pain is one of the most common clinical symptom with unclear pathogenesis,which causes difficulty in patien's work and daily life. Previous studies have shown that P2X3 receptor participates in the pathological process of acute and chronic inflammatory pain. This paper focuses on the functions of P2X3 receptor in inflammatory pain and its relationship with TRPV1 receptor,inflammatory mediator and Epac-PKC signal transduction pathway,thereby provides a new thought for research and treatment of this disease.

Effects of doxorubicin on neuropathic pain in chronic sciatic nerve constriction injury rats and its underlying mechanism / 中国药理学通报

Aim To observe the analgesic effect of doxorubicin ( DOX) on chronic sciatic nerve constric-tion injury (CCI) rat model, and analyze the underly-ing mechanism from the ultrastructure of sciatic nerve ganglion and the expressions of some apoptotic pro-teins.Methods A total of 60 SD rats were randomly divided into four groups: sham operation group ( Sham ) , CCI model group ( Model ) , sham operation+DOX 5 mg· kg -1 group ( Sham+DOX) , CCI mod-el +DOX 5 mg· kg -1 group (Model+DOX).DOX was given by caudal vein injection after model estab-lishment .Sham group and model group were given the same amount of saline . The mechanical withdrawal threshold and thermal withdrawal latency were deter-mined by behavioral test .The ultrastructural changes of L4-5 DRG were examined by light microscopy and scanning electron microscopy , respectively .The pro-tein expression levels of Bax , Bcl-2 , PKCɑ, PKCδand PKCε in DRG tissues were determined by Western blot.Results The fluorescence of DOX was found in DRG after DOX was given intravenously .In compari-son with sham group , the thermal and mechanical pain thresholds had no obvious changes in sham +DOX group, while the thresholds were decreased obviously seven days after surgery in model group .In comparison with model group , the pain thresholds in model +DOX group increased significantly , which lasted for the en-tire observation time of six days .The ultra-structure of tissues was damaged obviously in both sham +DOX group and model+DOX group.The protein expression of Bax/Bcl-2 increased, while the expressions of PKCδand PKCεdecreased with DOX injection .Conclusions DOX can retrograde and reach the DRG tissues after intravenous administration . The attenuation effect of DOX on neuropathic pain is related to the apoptosis in-duced by the down-regulation of PKCδ and PKCε in DRG cells.

A new isolate of thermophilic and organic solvent tolerant bacteria for lipase production using basal medium of palm kernel cake 80-87

@#Aims: This research focused on the selection of potential strains especially bacteria that can grow effectively in palm kernel cake (PKC) and produce high amount of thermostable and solvent tolerant (TS-OST) lipase. The work involved the exploration of renewable PKC as potential fermentation medium for discovery to novel TS-OST lipase that would have excellent tolerance and activity in presence of organic solvents with high temperatures for industrial applications.Methodology and results: Using palm kernel cake (PKC) as source of thermophilic bacteria, 53 bacterial strains were found survived at temperature 65 °C. However, after subcultured several times, only 17 strains were found as pure thermophilic strains. Preliminary screening both qualitative and quantitative was performed to all 17 potential thermophilic bacterial strains and showed that only 11 purified thermophilic strains are lipase producer. Strain PKC-P1 produced highest enzyme activity (11.13 U/g), followed by PKC-P13 and PKC-C9. The lowest enzymeactivity was lipase produced byPKC-C10 (0.76U/g). Strain PKC-P1 has been classified as Gram negative bacteria and identified as Bacillus smithiistrain PKC_P1.Conclusion, significance and impact of study: PKC as a by-product of oil palm industry consistsof many nutrients that can give benefits towards industry and can be utilized in order to produce enzymes like lipases. From these results, it could be concluded that this lipase stable at temperature 65 °C and pH 7 and may be a potential candidate to be used in a variety of biotechnological applications. This finding revealed that a bacterial strain obtained from oil-rich environment which is PKC through isolation process has potential as a source of more economical enzyme to be applied in biotechnology industr

Xijiao Dihuang decoction combined with Yinqiao powder inhibits TNF-α-induced permeability increase in PMVEC via PKC-SSeCKS pathway / 中国病理生理杂志

AIM:To investigate the molecular mechanism of Xijiao Dihuang decoction combined with Yinqiao powder (XDY) in treating viral pneumonia, and the effects of XDY on TNF-α-induced permeability in pulmonary microvascular endothelial cells (PMVEC) and the role of PKC-SSeCKS pathway involved.METHODS:The electric conductivity method was used to detect transendothelial electrical resistance (TER) of primarily cultured PMVEC on Transwell chamber at different time points to determine the permeability of PMVEC.After pretreatment for 24 h, the activity of PKC, TER, and the expression of SSeCKS at mRNA and protein levels were detected.Laser scanning confocal microscopy was used to observe the location of SSeCKS and construction of F-actin in PMVEC.RESULTS:The permeability of PMVECs induced by TNF-α reached the peak at 24 h.Compared with control group, the TER in TNF-α group was decreased, and the activity of PKC was increased.Compared with TNF-α group, the activity of PKC in TNF-α with PKC inhibitor group and TNF-α with XDY group was decreased, while the TER was increased, without difference from control group.Compared with control group, the mRNA expression of SSeCKS and phospho-SSeCKS was increased in PMVEC of TNF-α group, but decreased in TNF-α with XDY group compared with TNF-α group.In control group, F-actin was mainly located around the nucleus and at cytoplasmic borders of PMVEC, forming the dense peripheral bundle, and SSeCKS was evenly scattered in the cell.In TNF-α group, the dense peripheral bundle of F-actin surrounding the cells almost disappeared, and SSeCKS was concentrated around the nucleus.Compared with TNF-α group, the distribution and the structure of F-actin and SSeCKS nearly returned to normal in TNF-α with XDY group.CONCLUSION:XDY inhibits the activation of PKC signaling pathway in PMVEC caused by TNF-α to reduce the mRNA expression of SSeCKS and the phosphorylation of SSeCKS, thus preventing the deformation of endothelial cells and reducing the permeability of PMVEC.

STC2 Suppresses Breast Cancer Cell Migration and Invasion Via the PKC-Claudin-1-mediated Signaling / 医学研究杂志

Objective To study the effect of STC2 on invasion and metastasis of breast cancer cells and its mechanism.Methods By 231 HM shRNA interference cell STC2,we observed fiber cells expressing form,number plate cloning experiment statistical analysis.Immune co-precipitation (CO-IP) for testing related protein expression.Results By 231 HM STC2 cells expressing shRNA interference,231 HM presents high transfer characteristics of fiber cell morphology,cell invasion and metastasis ability of increase at the same time;On the contrary,after 231 cells expressing STC2,cell invasion and metastasis ability induced.In addition,after reducing STC2 expression of 231 HM cells,its resistance to radiation-inducled apoptosis and expression of STC2 after 231 reduced,ability to resist radiation induced apoptosis of cells induled too.Conclusion Collectively,these results indicate that STC2 may inhibit EMT at least partially through the PKC/Claudin-1-mediated signaling in human breast cancer cells.

The effects of PKC activation on the epithelial-mesenchymal transition of oral squamous cell cancer cells / 实用口腔医学杂志

Objective:To study the effects of activating protein kinase C (PKC)on oral squamous-cell cancer(OSCC) cell epithelial-mesenchymal transition(EMT).Methods:Plasmid pCMV6-AC-GFP-P120ctn was used to transfect HN12 cells to make P120-catenin (120ctn) overexpress and thereafter PKC activator PMA (phorbol 12-myristate 13-acetate) was added to the culture.Real-time fluorescent quantitative PCR and Western blot were adopted to test mRNA and protein expression of PKC,P120ctn,E-cadherin(E-cad),N-cadherin(N-cad) and Vimentin(Vim).Transwell cell invasion and cell migration assay were used to test the invasion and migration capacity before and after the activation.Results:When PKC was activated by PMA,the expression of P120ctn and E-cad were decreased,the cell morphology changed,nRNA and protein expression of mesenchymal marker protein N-cad and Vim increased significantly.Meanwhile,the migration and invasion capacity of the tumor cells increased significantly(P ＜ 0.05).Conclusion:In OSCC cells,PKC may be involved in promoting EMT and the metastasis and invasion by adjusting P120ctn/E-cad expression and cell adhesion.

Effects of electroacupuncture preconditioning on expression of aquaporin-1 and activity of protein kinase C in myocardium of rats with acute myocardial ischemia-reperfusion injury / 中国针灸

<p><b>OBJECTIVE</b>To explore the partial action mechanism and the myocardial protective effect differences between electroacupuncture (EA) preconditioning at "Neiguan"(PC 6) and "Taiyuan"(LU 9) in rats with acute myocardial ischemia-reperfusion injury.</p><p><b>METHODS</b>Ninety-six Wistar rats were randomly assigned into a sham-operation group, a model group, a Neiguan group and a Taiyuan group, 24 rats in each one. The rats in the Neiguan group and Taiyuan group were treated with EA (2 Hz in frequency, 1 mA in intensity) at "Neiguan" (PC 6) and "Taiyuan" (LU 9) respectively, 20 min per treatment, once a day for consecutive 7 days. The rats in the sham-operation group and model group were treated with immobilization for the same time, and no EA was given. The model of myocardial ischemia-reperfusion injury was established in the model group, Neiguan group and Taiyuan group 24 h after the end of EA, while the rats in the sham-operation group were treated with sham operation (no ligation was made during surgery). The myocardial ischemic size, infarction size, activity of protein kinase C (PKC) and expression of aquaporin1 (AQP1) in each group were detected.</p><p><b>RESULTS</b>Compared with sham-operation group, the myocardial ischemic size, infarction size, AQP1 expression and PKC activity in the model group were significantly increased (all<0.01); compared with the model group and Taiyuan group, the myocardial ischemic size, infarction size, PKC activity and AQP1 expression were significantly decreased in the Neiguan group (<0.01,<0.05). By Pearson correlation analysis, the changes of AQP1 expression were positively correlated with those of PKC activity after EA preconditioning.</p><p><b>CONCLUSIONS</b>EA preconditioning at "Neiguan" (PC 6) could significantly decrease myocardial AQP1 expression and PKC activity in rats with acute myocardial ischemia-reperfusion injuing, but the effect of EA preconditioning at "Taiyuan"(LU 9) is not obvious; its protective effect is likely to be achieved by inhibiting PKC activity and AQP1 expression.</p>

Effect of the petroleum ether extract from Bushen Huoxue Decoction on promoting BMSCs migration via Wnt5a/PKC signaling pathway / 中成药

AIM To investigate the effect and mechanism of petroleum ether extract from Bushen Huoxue Decoction (BSHXD,Rehmanniae Radix Praeparata,Cuscutae Semen,Psoraleae Fructus,etc.) on rat BMSCs migration.METHODS Bone marrow mesenchymal stem cells isolated from whole bone marrow of rats were amplified by adherent culture in vitro.Flow cytometry was employed to detect the cell surface antigens of the third generation cells.Migration examination of cells treated with petroleum ether extract from BSHXD at concentrations of 25,50,100 and 200 μg/mL was accomplished by cell scratch test and Transwell assay.Expressions of WntSa and PKC protein were traced by Western blot,and so were the mRNA expressions of Wnt5a and PKC by RT-PCR.RESULTS Positive expressions of CD29,CD44 and CD90 in the passage 3 of BMSCs but negative expression of CD45 were observed.The cells given different concentrations of petroleum ether extract from BSHXD groups displayed a significantly higher wound healing speed than the control group after 6 h and 12 h cell scratch (P ＜ 0.05).100 μg/mL BSHXD was shown to be the most active concentration for promoting cell migration by Transwell migration experiments,with a statistically significant difference (P ＜ O.O1).Compared with the control group,the levels of Wnt5a mRNA in the BSHXD groups were significantly higher (P ＜ 0.05),and the PKC mRNA level in 100 μg/mL petroleum ether extract from BSHXD group was significantly increased as well (P ＜0.01)by RT-PCR.Although BSHXD groups brought forth significant improvement in both the expressions of Wnt5a and PKC protein (P ＜ 0.01),the 100 μg/mL concentration conferred the highest (P ＜ 0.01).CONCLUSION Petroleum ether extract from BSHXD can promote BMSCs migration in vitro,and the mechanism may lie in its association with WntSa signaling pathway.

Parthenolide enhances the apoptosis induced by PKC inhibitor in human gastrointestinal stromal tumors cell lines / 基础医学与临床

Objective To investigate the effect of parthenolide ( PTL) and PKC inhibitor on human gastrointestinal stromal tumor (GIST) cell proliferation and apoptosis and the mechanism involved .Methods Human GIST cell lines were cultured in vitro, and the cell proliferation rate of GIST , was determinate by MTT;flow cytometry was used to test the early apoptosis rate of GIST;Western blot assay was applied to detect the expression of endoplasmic reticulum stress-related proteins , GRP78 and GADD153.There were four groups: control group , PTL group, PKC inhibitor group , combine PTL and PKC inhibitor group .Results PTL and PKC inhibitor combination therapy for GIST was sig-nificantly more effective than a single-drug therapy (P<0.05);as for the early apoptosis rate , the combination ther-apy for GIST cells was significantly higher than that medication alone group (P<0.05).the expression of endoplas-mic reticulum stress-associated protein GRP 78 and GADD153 was obviously higher in PTL and PKC inhibitor combi-nation group than that in medication alone group (P<0.05).Conclusions PTL and PKC inhibitor combination therapy for GIST cells can induce apoptosis , which is possibly mediated via endoplasmic reticulum stress pathway .