Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Journal of Practical Stomatology ; (6): 674-678, 2017.
Article in Chinese | WPRIM | ID: wpr-668135

ABSTRACT

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.

2.
Chinese Acupuncture & Moxibustion ; (12): 157-161, 2017.
Article in Chinese | WPRIM | ID: wpr-247756

ABSTRACT

<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>

3.
The Korean Journal of Parasitology ; : 355-365, 2014.
Article in English | WPRIM | ID: wpr-70517

ABSTRACT

The enteric protozoan parasite Entamoeba histolytica is the causative agent of human amebiasis. During infection, adherence of E. histolytica through Gal/GalNAc lectin on the surface of the amoeba can induce caspase-3-dependent or -independent host cell death. Phosphorylinositol 3-kinase (PI3K) and protein kinase C (PKC) in E. histolytica play an important function in the adhesion, killing, or phagocytosis of target cells. In this study, we examined the role of amoebic PI3K and PKC in amoeba-induced apoptotic cell death in Jurkat T cells. When Jurkat T cells were incubated with E. histolytica trophozoites, phosphatidylserine (PS) externalization and DNA fragmentation in Jurkat cells were markedly increased compared to those of cells incubated with medium alone. However, when amoebae were pretreated with a PI3K inhibitor, wortmannin before being incubated with E. histolytica, E. histolytica-induced PS externalization and DNA fragmentation in Jurkat cells were significantly reduced compared to results for amoebae pretreated with DMSO. In addition, pretreatment of amoebae with a PKC inhibitor, staurosporine strongly inhibited Jurkat T cell death. However, E. histolytica-induced cleavage of caspase-3, -6, and -7 were not inhibited by pretreatment of amoebae with wortmannin or staurosporin. In addition, we found that amoebic PI3K and PKC have an important role on amoeba adhesion to host compartment. These results suggest that amebic PI3K and PKC activation may play an important role in caspase-independent cell death in Entamoeba-induced apoptosis.


Subject(s)
Humans , Apoptosis , Caspases/metabolism , Entamoeba histolytica/enzymology , Hydrolysis , Jurkat Cells , Phosphatidylinositol 3-Kinases/metabolism , Protein Kinase C/metabolism , T-Lymphocytes/parasitology
4.
The Korean Journal of Physiology and Pharmacology ; : 51-56, 2013.
Article in English | WPRIM | ID: wpr-728172

ABSTRACT

Many intracellular proteins and signaling cascades contribute to the sensitivity of N-methyl-D-aspartate receptors (NMDARs). One such putative contributor is the serine/threonine kinase, protein kinase C (PKC). Activation of PKC by phorbol 12-myristate 13-acetate (PMA) causes activation of extracellular signal-regulated kinase (ERK) and promotes the formation of new spines in cultured hippocampal neurons. The purpose of this study was to examine which PKC isoforms are responsible for the PMA-induced augmentation of long-term potentiation (LTP) in the CA1 stratum radiatum of the hippocampus in vitro and verify that this facilitation requires NMDAR activation. We found that PMA enhanced the induction of LTP by a single episode of theta-burst stimulation in a concentration-dependent manner without affecting to magnitude of baseline field excitatory postsynaptic potentials. Facilitation of LTP by PMA (200 nM) was blocked by the nonspecific PKC inhibitor, Ro 31-8220 (10microM); the selective PKCdelta inhibitor, rottlerin (1microM); and the PKCepsilon inhibitor, TAT-epsilonV1-2 peptide (500 nM). Moreover, the NMDAR blocker DL-APV (50microM) prevented enhancement of LTP by PMA. Our results suggest that PMA contributes to synaptic plasticity in the nervous system via activation of PKCdelta and/or PKCepsilon, and confirm that NMDAR activity is required for this effect.


Subject(s)
2-Amino-5-phosphonovalerate , Acetophenones , Benzopyrans , Excitatory Postsynaptic Potentials , Hippocampus , Indoles , Long-Term Potentiation , Nervous System , Neurons , Phorbols , Phosphotransferases , Protein Isoforms , Protein Kinases , Proteins , Receptors, N-Methyl-D-Aspartate , Spine
5.
Rev. Fac. Med. (Caracas) ; 35(1): 40-44, ene.-jun. 2012. tab
Article in Spanish | LILACS | ID: lil-682991

ABSTRACT

En estudios previos, se ha descrito un disminución de la activación y actividad citotóxica de las células NK en los pacientes infectados con hepatitis C; sin embargo, se desconoce el mecanismo por el cual éste fenómeno ocurre. En el presente reporte se estudió el efecto de la proteína E2 de la envoltura del virus o de la estimulación de su receptor con el anticuerpo anti-CD81 sobre la fosforilación de tirosinas, serinas, las enzimas: proteína quinasa C y fosfoinositol 3 quinasa, el factor de transcrición Nfkb y el intercambiador de nueclotidos VAV de células NK de controles normales estimulados con anti-CD16. Ambos, la proteína E2 y anti-CD81, combinado o por separado inducen una disminución de la fosforilación de tirosinas y serinas, así como una marcada disminución de la fosforilación de PKC, NFkB, PI3K y en menor grado VAV. Se concluye que la proteína E2 sola y en conjunto con anti-CD81 inducen señales inhibitorias responsables de la disminución en la activación de las células NK de pacientes infectados por el VHC y que éste fenómeno puede ser responsable de la cronicidad que se reporta en dicha enfermedad


The decrease in NK cell activation and cytotoxic activity in patients infected with hepatitis C virus has been described; however, the mechanism by whcih this phenomenon occurs is not known. In the present report, the effect of the E2 protein of the virus envelope or the stimulation of its receptor CD81 with the antibody anti-CD81 on the phosphorylation of tyrosines, serine, the enzymes protein kinase C, phosphoinositol kinase 3 (PI3K), the transcription factor NfkB and the nucleotide exchange protein VAV was assessed in NK cells from normal controls stimulated with anti-CD16. Both the protein E2 and anti-CD81 by themselves or combined, generated a decrease in tyrosine, serine, and a marked decrease in the phosphorylation of PKC, NfkB, PI3k and in less extent in VAV. It is concluded that the E2 protein alone and combined with anti-CD81 induce inhibitory signals responseible for the decrease in the activation of NK cells of infected HCV patients and it could be responsible for the chronicity observed in this disease


Subject(s)
Humans , /therapeutic use , Killer Cells, Natural/virology , Hepatitis C/therapy , Hepatitis C/virology , Protein Kinase C/therapeutic use , /adverse effects , /therapeutic use , Proto-Oncogene Proteins c-vav/therapeutic use , Receptors, IgG/therapeutic use , Allergy and Immunology
6.
Basic & Clinical Medicine ; (12)2006.
Article in Chinese | WPRIM | ID: wpr-595084

ABSTRACT

Objective To investigate the effects of siRNAs targeted protein kinase C ?(PKC?) on the proliferation and apoptosis of A549 cell line.Methods Six PKC? siRNAs were designed and chemical synthesized. Candidate PKC? siRNA was transfected into A549 cells,PKC? mRNA level was determined by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). Then,the effects of more effective PKC? siRNAs on A549 were further investigated by using clone formation assay,Hoechst 33258 staining,propidium iodide (PI) staining,Annexin V-FITC and PI dual staining and western blot. Results Six candidate PKC? siRNAs were designed and named as No.1,No.2,No.3,No.4,No.5 and No.6 PKC? siRNA. Compared with controls,PKC? mRNA levels were all significantly downregulated and the cell proliferation was inhibited in A549 cells treated with candidate PKC? siRNAs except No.5 (P

7.
Korean Journal of Anatomy ; : 371-380, 2003.
Article in Korean | WPRIM | ID: wpr-654612

ABSTRACT

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi-odiopiperzine (ETP) metabolite, namely gliotoxin. Gliotoxin commonly react with sulfhydryl groups, and then, forms hydrogen peroxide. These fungal toxins induce apoptotic cell death in various cells. Apoptosis induced by gliotoxin need calcium. Effect of calcium preconditioning was not reported in gliotoxin-induced apoptosis. To examine the effect of protein kinase C (PKC) and calcium which was regulate caspase-3, PKC and calcium preconditioning before gliotoxin treatment, apoptotic agents such as bcl-2 family, caspase-3 and DNA fragmentation in A7r5 cell line from rat smooth muscle cell were studied. These results showed that gliotoxin induces the expression of bad of bcl-2 family, caspase-3 activation and DNA fragmentation in A7r5 cells. Gliotoxin treatment followed by calcium and PKC preconditioning suppress the Bad of bcl-2 family, and inhibited caspase-3 activation, respectively. These results suggest that PKC and calcium preconditioning protect the gliotoxin-induced apoptosis, through the protection of pro-apoptotic bcl-2 family in A7r5 cells.


Subject(s)
Animals , Humans , Rats , Apoptosis , Aspergillus , Calcium , Caspase 3 , Cell Death , Cell Line , DNA Fragmentation , Fungi , Gliotoxin , Hydrogen Peroxide , Muscle, Smooth , Mycotoxins , Myocytes, Smooth Muscle , Protein Kinase C
8.
Korean Journal of Obstetrics and Gynecology ; : 1393-1400, 2001.
Article in Korean | WPRIM | ID: wpr-167808

ABSTRACT

OBJECTIVE: To determine of the regulation of cyclooxygenase-2 (COX-2) expression by Interleukin-1beta in WISH cells. METHODS: Amnion WISH cells were incubated in media containing increasing concentrations of IL-1beta or with various inhibitors. Increased COX-2 expression was determined by Western blot analysis with anti-COX-2 antibody. Concomitant measurements of culture media PGE2 were made by an enzyme immunoassay. RESULTS: The COX-2 and prostaglandin E2 production induced by IL-1beta increased in a dose- and time-dependent manner. One of the regulating factors that induced COX-2 by IL-1beta was protein kinase C (PKC). PKC inhibitor, Ro 31-8220 was pretreated and continued treating by IL-1beta. Then, PKC inhibitor completely blocked COX-2 protein induction by IL-1beta. In contrast, COX-2 induction by IL-1beta after pretreating PKC stimulator, phobol 12-myristate 13-acetate was potentiated with synergism. Another factor in controlling COX-2 protein induction was identified as phosphatidylinositol 3-kinase (PI 3K). COX-2 protein induction by IL-1beta after pretreating PI 3K inhibitors, wortmannin and LY294002 strongly increased. This kind of result reflected that PI 3K act as negative regulator. COX-2 induction by IL-1beta was known to be regulated in not only transcription step, but also translation step after performing experiment of actinomycin and cycloheximide treatment. CONCLUSION: COX-2 protein and prostaglandin E2 production induced by IL-1beta were controlled by many factors in amnion cell. Among those factors, PKC and PI 3K have an important role, but their control mechanism act as positive and negative, respectively.


Subject(s)
Amnion , Blotting, Western , Culture Media , Cycloheximide , Cyclooxygenase 2 , Dactinomycin , Dinoprostone , Immunoenzyme Techniques , Interleukin-1beta , Phosphatidylinositol 3-Kinase , Protein Kinase C
9.
Korean Journal of Physical Anthropology ; : 119-128, 2000.
Article in Korean | WPRIM | ID: wpr-110819

ABSTRACT

Aspergillus funigatus and other pathogenic fungi synthesize a toxic epidithi- odiopiperzine (ETP) metabolite called gliotoxin. Gliotoxin is an epidithiodiopiperzine compound which can both react with sulfhydryl groups and form hydrogen peroxide. The fungal toxin gliotoxin induces apoptotic cell death in a variety of cells. Apoptosis induced by gliotoxin need calcium but effect of calcium preconditioning is unknown by gliotoxin. We studied the effect of protein kinase C and calcium preconditioning on gliotoxin-induced apoptosis in H9c2 cell. PKC and calcium preconditiong inhibited DNA fragmentation by gliotoxin. From this above results suggest that gliotoxin induce apoptosis via caspase-3 activation, because caspase-3 inhibitor (DEVD-CHO) didn't induce apoptosis in gliotoxin treated H9c2 clls. Calcium and PKC preconditioning inhibit caspase-3 activation by gliotoxin. These data means that PKC preconditioning is related with caspase-3 regulate in gliotoxin-induced apoptosis.


Subject(s)
Apoptosis , Aspergillus , Calcium , Caspase 3 , Cell Death , DNA Fragmentation , Fungi , Gliotoxin , Hydrogen Peroxide , Protein Kinase C , Protein Kinases
10.
Korean Journal of Anatomy ; : 571-578, 2000.
Article in Korean | WPRIM | ID: wpr-651183

ABSTRACT

Paclitaxel (taxol) is known as effective drug inhibition of cell cycle encouraging activity in human ovarian and metastatic breast cancers and malignant melanoma. It is an antimicrotubule agent that is believed to mediate its antineoplastic effects by inducing mitotic arrest followed by apoptosis. The relation between phorbol 12 myristate 13 acetate (PMA), protein kinase C (PKC) activator, and taxol-induced apoptosis is not well understood until now. This study was performed to investigate the effects of PMA on the signal transduction pathways of taxol-induced apoptosis in MCF-7 human breast carcinoma cells. Taxol-induced apoptosis is attenuated by curcumine, JNK inhibitor, and pyrrolidine dithiocarbamate (PDTC), inhibitor of NFkB. Pretreatment with PKC activator (PMA) or protein kinase A (PKA) activators (forskolin and dibutyryl cAMP) inhibited taxol-induced apoptosis in MCF-7 cells. In addition, thapsigargin, a specific inhibitor of endoplasmic reticulum(ER) Ca(2+)-ATPase and CaCl2, also blocked the activation of caspases by taxol. From these results suggest that taxol-induced apoptosis may be mediated via JNK or NFkB pathway and PKC activation.


Subject(s)
Humans , Apoptosis , Breast , Breast Neoplasms , Caspases , Cell Cycle , Curcumin , Cyclic AMP-Dependent Protein Kinases , MCF-7 Cells , Melanoma , Myristic Acid , Paclitaxel , Protein Kinase C , Signal Transduction , Thapsigargin
11.
Korean Journal of Otolaryngology - Head and Neck Surgery ; : 685-695, 1998.
Article in Korean | WPRIM | ID: wpr-650483

ABSTRACT

BACKGROUND AND OBJECTIVES: The exact pathogenesis of cholesteatoma remains unknown in spite of several theories that have been formulated. The most characteristic histologic finding of cholesteatoma is the proliferation of the squamous cell lining of the lesion. Protein Kinase C (PKC) is a family of phospholipid-dependent serine/threonin protein kinase that sends extracellular signals across the cell surface in order to regulate epithelial cell groweth and differentiation. This study attempted to provide the evidence for the role of PKC in cholesteatoma. MATERIALS AND METHODS: Twenty-five cholesteatoma specimens were obtained from patients for western blotting, immunohistochemical study, RT-PCR, and densitometry. RESULTS: The results of western blotting revealed that considerably lower levels of PKCalpha, PKCbeta, and PKCepsilon protein were detected in cholesteatoma than in the posterior auricular skin. In the immunohistochemical study, PKCalpha, PKCbeta, and PKCepsilon were detected both in the basal and suprabasal layer of posterior auricular skin, but they were not detectable in cholesteatoma. The results of PCR for PKCalpha, PKCbeta, and PKCepsilon showed that there were no differences between cholesteatoma and posterior auricular skin regarding the mRNA expression. CONCLUSION: Downregulation of PKCalpha, PKCbeta, and PKCepsilon in cholesteatoma suggests that abnormal epithelial growth is a possible mechanism of cholesteatoma. The results suggest the following there is an abnormal signal transduction through the PKC pathway in cholesteatoma: downregulation of PKC takes place in the post-transcription phase, and downregulation of PKC is associated with prolonged chronic inflammation of cholesteatoma.


Subject(s)
Humans , Blotting, Western , Cholesteatoma , Densitometry , Down-Regulation , Epithelial Cells , Inflammation , Polymerase Chain Reaction , Protein Kinase C , Protein Kinases , RNA, Messenger , Signal Transduction , Skin
12.
Journal of Practical Stomatology ; (6)1996.
Article in Chinese | WPRIM | ID: wpr-540980

ABSTRACT

Objective: To investigate the expression and distribution of G protein and protein kinase C (PKC) under the mechanical pressure in rabbit mandibular condylar chondrocytes (MCCs) and to study the role of G protein in PKC signalling pathway. Methods:MCCs from two-week-old New Zealand rabbits were cultured. After treatment under continuous pressure of 90 kPa for 60 min or 360 min by hydraulic pressure controlled cellular strain unit, the expression of G?q/11 protein was examined by Western Blot. The expression and distribution of PKC was observed by immunocytochemical staining. Results:Gaq/11 protein in MCCs treated by 90 kPa for 60 min and 360 min was increased by 163.7% and 65.8% respectively(P0.05). PKC in control cells distributed uniformly in the cytoplasm. After been pressed under 90 kPa for 60 min,PKC translocated to the membrane and, partly,into nuclei. When the pressure prolonged to 360 min, PKC distributed uniformly again in cytoplasm. By treatment of G protein inhibitor, the translocation of PKC under 90 kPa of 60 min was not observed. Conclusion:Feasible pressure may promote G protein expression and activate PKC. The activation of PKC signalling pathway is mediated by G protein.

13.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-580447

ABSTRACT

Objective To investigate the protection of Liuwei Dihuang Jiawei Capsula(LDJ Capsula,Rehmanniae Capsula of Six Ingredients) on diabetic nephropathy(DN) rats′ kidney and effect on renal protein kinase C(PKC) activity and connective tissue growth factor(CTGF) of DN rats.Methods The DN rat models were induced by ip injection of streptozotocin(STZ).The rats were randomly divided into five groups: control group; DN model group;Lotensin group;LDJ Capsula group;and Lotensis and LDJ Capsula combination group.Drug intervention term was 12 weeks.Renal ultrastructure was observed by transmission electron microscope and Masson staining.Relative kidney weight,blood glucose level,serum and urine creatinine content,creatinine clearance,excretion rate of the 24 hour urine protein,renal PKC activity,and CTGF expression in renal cortex were measured by immunohistochemistry.Results Deposition of collagen in renal of DN rats was conspicuous.Relative kidney weight,blood glucose level,serum and urine creatinine content,creatinine clearance,excretion rate of 24 h urine protein,renal PKC activity and CTGF expression of DN rats increased obviously.All Lotensin,LDJ Capsula,and the combination of these two drugs could decrease renal PKC activity and CTGF expression and ameliorate proteinuria and renal function of DN rats.At the same time they all could abate the deposition of collagen in renal of DN rats.Combination of these two drugs could decrease renal PKC activity and CTGF expression more ob-viously and at the same time had more notable protective effect on kidney of DN rats.Conclusion All Lotensin,LDJ Capsula,and the combination of these two drugs could protect kidney of DN rats.The combination of these two drugs has more obviously protective effect than using Lotensin only.

14.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-578960

ABSTRACT

Objective To investigate the effect of Fushenjiangxianning on renal protein kinase C(PKC),renal vascular endothelial growth factor(VEGF),renal platelet-derived growth factor ?(PDGF-?),and renal protection in diabetic nephropathy(DN) rats.Methods The diabetic SD rats induced by STZ were divided into four groups: diabetic control group,Fushenjiangxianning group,Irbesartan group, and Fushenjiagxianning combined with Irbesartan group,and the normal control group as well.After the experimental rats in every group were respectively treated for 12 weeks by above intervention methods,the relative kidney weight,blood sugar,urea nitrogen(Bun),serum creatinine(Scr),and urinary albumin excretion rate(UAER) were detected by routine analysis methods,and PKC and VEGF in renal tissue were detected by immunohistochemical techniques,and PDGF-? in renal tissue was detected by Western blotting,and ultramicrostructure of kidney was observed by transmission electron microscope.ResultsThe expression of renal cortex PKC and VEGF was increased in diabetic rats.The ultramicrostructure of kidney was noticeably changed,and the blood sugar,UAER,BUN,Scr,relative kidney weight,and PDGF-? were significantly increased in diabetic rats.While the above indexes in Fushenjiangxianning group,Irbesartan group,and Fushenjiangxianning combined with Irbesartan group were significantly lower than those in diabetic control group(P

15.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-578715

ABSTRACT

Objective To investigate the antithrombosis effects of Buyang Huanwu Decoction(BHD) and its active fractions on cultured vascular endothelial cells(VEC) following the stimulation of thrombin and their mechanism.Methods The human umbilicus vein endothelial cells(ECV 304) were cultured in media containing 10 U/mL thrombin and different dosese of drugs.The levels of tPA and PAI-1 were detected by ELISA,the expression of TF,TFPI,and TM mRNA was measured by RT-PCR,and the expression of PKC? was examined by immunohistochemical staining 24 h later.Results Compared to the control without any treatment,the release of tPA was increased evidently(P0.05).Compared to the data after the mere stimulus of thrombin,each dose of BHD increased the release of tPA(P0.05);And glycoside(1.25 mg/mL) increased the release of tPA(P

16.
Chinese Traditional and Herbal Drugs ; (24)1994.
Article in Chinese | WPRIM | ID: wpr-572679

ABSTRACT

Object To investigate the effect of puerarin (Pue) on renal protein kinase C (PKC) activity, kidney structure and function in diabetic rats. Methods STZ-induced diabetic rats were randomly divided into five groups: Diabetic rats model group (DM), Pue (500, 250, 125 mg/kg) treatment group, and VitE group, in addition, normal rats for control group. All rats were given by ig for 12 weeks. Kidney function and kidney index were determined; The PKC activity was measured by ELISA. The excretion of microalbuminuria (MAU) was measured by radio-immunoassay, and kidney tissue was observed by light-microscope and transmission electron microscope. Results The excretion of MAU, kidney index (kidney weight/body weight) and PKC activity in diabetic rats were significantly increased. The excretion of MAU, and PKC activity were markedly decreased in Pue treatment group, and kidney pathologic changes of diabetic rats in Pue treatment group were improved. Conclusion Pue can ameliorate early kidney hy-perdynamic abnormality in diabetic rats, possess protective effect on kidney of diabetic rats, whose mechanism may be associated partly with a down-regulation of PKC activity.

17.
Chinese Journal of Immunology ; (12)1985.
Article in Chinese | WPRIM | ID: wpr-536890

ABSTRACT

Abstract Objective: To investigate the regulatory effect of PAF on early events in signal transduction during T-cell activation. Methods:T-cell activation was achieved by stimulation of human T cells with CD3 mAb or PMA/ionomycin in the presence or absence of PAF. T cell Pro-liferatilon was determined by 3 H-thymidine incorporation, IL-2 production was measured by MTT method, IL-2R(CD25)expression was evaluatedby flow cytometry and,PKC activity was assayed by the method described by Hauschildt. Results:PAF inhibited CD3 mAb-induced T-cell pro-liferation, IL-2 production and CD25 expression. AIthough it inhibited T-cell proliferation and IL-2 production induced by PMA/ionomycin, PAFfailed to inhibit IL-2 production induced by PMA/ionomycin.The translocation of PKC was also inhibited by PAF if T cells were activated byCD3mAb. Conclusion: PAF inhibits T-cell activation via its inhibitory effect on PKC activation. Its differential effect on IL-2 production suggeststhat PAF regulatory more early events in signal transduction such as the activation of phospholipase C ?-1.

18.
Chinese Journal of Immunology ; (12)1985.
Article in Chinese | WPRIM | ID: wpr-535196

ABSTRACT

PHA,PMA or OKT3 McAb alone can not induce the proliferative responses of purified resting T cells,which enables us to comparise the effects of exogenous IL—2,IL—4 and IL—6 on the activation and proliferation of T cell.PHA can induce purifeid resting T cells responding to exgenous IL—2,IL—4 or Il—6 and anti—Tac(p55)McAb only blocked the proliferative response of PHA—stimulated T cells responding to IL—2.PMA can induce purified resting T cells responding to exogenous IL—2 or IL—4 but not Il—6.OKT3 McAb only induced the purified resting T cells responding to exogenous IL—2.Cyclsporin A,an immunosuppressant(CsA),inhibited the proliferative responses of PHA—stimulated T cells responding to exogenous IL—2,IL—4 or IL—6,but in the kinetic study of inhibitory affect of CsA,the results were completely different.Our data suggest that IL—2,IL—4 and IL—6 activate T cell by different pathway.

19.
Acta Anatomica Sinica ; (6)1955.
Article in Chinese | WPRIM | ID: wpr-576766

ABSTRACT

Objective To determinted whether GM1 had a protective effect on injury induced by serum-deprivation and the possible mechanism in PC12 cells. Methods The viability of PC12 cells was quantified by MTT after serum-deprivation.The number of apoptotic cells and necrotic cells were determined by Hoechst 33258/PI staining.And the change of PKC protein expression on PC12 cells' membrane and cytosols was detected by Western blotting. Results 1.The viability of PC12 cells decreased after serum-deprivation and the serum-deprivation for 24 hours was chosen as an injury model in this research.Most of the PC12 cells presented apoptosis 24 hours after serum-deprivation.In addition,the PC12 cells' cytosols PKC protein decreased,while the PC12 cells' membrane PKC protein increased significantly,and this result suggested PKC's translocation to membrane and its activation.2.The viability of PC12 cells preincubated with GM1 in high concentrations(10,1,0.1?mol/L) increased significantly and GM1 protected PC12 cells from apoptosis after serum-deprived injury.GM1 reduced the damage of serum-deprivation on PC12 cells and inhibited PKC protein translocation after injury.3.The repair function of GM1 was effective to neuronal resume after serum-deprived injury.Conclusion Neuroprotective effects of GM1 on serum-deprived injury may be partly mediated through the regulation of PKC pathways and it is helpful for the recovery after injury.

SELECTION OF CITATIONS
SEARCH DETAIL