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1.
Acta Anatomica Sinica ; (6): 105-112, 2024.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-1015145

ABSTRACT

Objective To study the microscopic structure and morphological characteristics of Zebrafish eyeball and retina at different developmental stages, and to lay a foundation for visual research model. Methods Select eight groups of zebrafish at different ages, with six fish in each group, 48 fish in total. Optical microscopy and transmission electron microscopy were used to observe the eyeball structure of Zebrafish at different developmental stages, and the thickness of retinal each layer was measured to analyze the temporal and spatial development pattern. The morphological characteristics of various cells in the retina and the way of nerve connection were observed from the microscopic and ultrastructural aspects, especially the structural differences between rod cells and cone cells. Results The retina of Zebrafish can be divided into ten layers including retinal pigment epithelial layer, rod cells and cone cells layer, outer limiting membrane, outer nuclear layer, outer plexiform layer, inner nuclear layer, inner plexiform layer, ganglion cell layer, nerve fiber layer, inner limiting membrane. Rod cells had a smaller nucleus and a higher electron density than cone cells. Photoreceptor terminals were neatly arranged in the outer plexiform layer, forming neural connections with horizontal cells and bipolar cells, and several synaptic ribbons are clearly visible within them. In Zebrafish retina, ganglion cell layer and inner plexiform layer are the earliest developed. With the growth and development of Zebrafish, the thickness of rod cells and cone cells layer and retinal pigment epithelial layer gradually increases, and the retinal structure was basically developed in about 10 weeks. Conclusion The retinal structure of Zebrafish is typical, with obvious stratification and highly differentiated nerve cells. There are abundant neural connections in the outer plexiform layer. The ocular development characteristics of Zebrafish are similar to those of most mammals.

2.
Acta Pharmaceutica Sinica ; (12): 3198-3203, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-999087

ABSTRACT

A flavoring agent and a suspension agent were prepared for extemporaneous compounding. The stability of the two agents before and after drug loading was investigated, and the taste of the suspension after extemporaneous compounding was evaluated by electronic tongue technology. The two agents remained stable under the conditions of influence factor test, accelerated test and long-term test. The appearance properties of the two agents did not change. The relative density of the flavoring agent was maintained at 1.053-1.075, and the pH was stable at 4.2-4.5. The relative density of the suspension agent was maintained at 0.999-1.022, and the pH was stable at 4.0-4.5. Seven kinds of drugs, including warfarin sodium tablets and spironolactone tablets, were mixed with these two oral solvents, and the content uniformity and stability were detected respectively. The results showed that the preparations could be evenly dispersed and the physical and chemical properties were stable. The results of taste evaluation showed that in captopril group and chloral hydrate group, the flavoring agent had the best effect on taste correction. In warfarin sodium group, rifampicin group, spironolactone group, vitamin B1 group and vitamin B2 group, the blending agents had the best effect on taste correction.

3.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-698499

ABSTRACT

BACKGROUND: Microwave treatment is a common physical therapy method that can increase the temperature and blood circulation of deep tissues, and is used for improving fracture repair. However, microwave treatment cannot be used if there is surgically implanted metal plate or screw. OBJECTIVE: To observe the dame of microwave treatment to the tissues surrounding the titanium alloy implants. METHODS: Forty-four New Zealand white rabbits were randomized into experimental and control groups. The model of the fracture at the middle of the femur was established in all rabbits, and the rabbits in the experimental group were implanted with titanium alloy internal fixation systems. A 30-day microwave treatment (2 450 MHz, 20 W or 40 W, 20 minutes daily) was applied to the fracture site in all rabbits at 3 days after operation. RESULTS AND CONCLUSION: After 20 W of wave microwave treatment, the temperature of tissues around the implants showed no significant increase or severe heat injury. While, 40 W of wave microwave treatment significantly increased the temperature of tissues around the implants and the tissue was damaged severely. Our results indicate that, the low-dosage microwave treatment may be a promising method in the rehabilitation therapy of fractures with titanium alloy internal fixation.

4.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-679395

ABSTRACT

Objective To evaluate the protecting effects of matrine on chemotherapy related hepatic lesion and its possible mechanism.Methods The positive rate and severity of hepatic lesion were compared between pa- tients being treated with or without matrine during chemotherapy processes.Furthermore,the difference of liver pro- tecting effect of this Chinese medicine between hepatitis B virus(HBV)infection chemotherapy patients and disinfec- tion patients were also analyzed.Results Both the rate of hepatic lesion and level of ALT in matrine treated group were much lower than those in untreated group in chemotherapy patients.The rate of hepatic lesion and level of ALT in HBV infection patients were higher than those in HBV disinfection patients in untreated group,while the signifi- cant difference of these two parameters between HBV infection patients and disinfection patients were disappeared in matrine treated group.Conclusion Matrine has hepatic protecting effect in chemotherapy related liver lesion.

5.
World J Gastroenterol ; 11(17): 2564-9, 2005 May 07.
Article in English | MEDLINE | ID: mdl-15849812

ABSTRACT

AIM: To investigate the mechanism of alpha-fetoprotein (AFP) in escaping from the host immune surveillance of hepatocellular carcinoma. METHODS: AFP purified from human umbilical blood was administrated into the cultured human lymphoma Jurkat T cell line or hepatoma cell line, Bel7402 in vitro. The expression of tumor necrosis factor related apoptosis-inducing ligand (TRAIL) and its receptor (TRAILR) mRNA were analyzed by Northern blot and Western blot was used to detect the expression of Fas and Fas ligand (FasL) protein. RESULTS: AFP (20 mg/L) could promote the expression of FasL and TRAIL, and inhibit the expression of Fas and TRAILR of Bel7402 cells. For Jurkat cell line, AFP could suppress the expression of FasL and TRAIL, and stimulate the expression of Fas and TRAILR. AFP also could synergize with Bel7402 cells to inhibit the expression of FasL protein and TRAIL mRNA in Jurkat cells. The monoclonal antibody against AFP (anti-AFP) could abolish these functions of AFP. CONCLUSION: AFP is able to promote the expression of FasL and TRAIL in hepatoma cells and enhance the expression of Fas and TRAILR in lymphocytes. These could elicit the escape of hepatocellular carcinoma cells from the host's lymphocytes immune surveillance.


Subject(s)
Carcinoma, Hepatocellular/physiopathology , Liver Neoplasms/physiopathology , Membrane Glycoproteins/genetics , Tumor Necrosis Factor-alpha/genetics , alpha-Fetoproteins/pharmacology , fas Receptor/genetics , Apoptosis , Apoptosis Regulatory Proteins , Carcinoma, Hepatocellular/immunology , Carcinoma, Hepatocellular/pathology , Fas Ligand Protein , Gene Expression Regulation, Neoplastic/drug effects , Humans , Jurkat Cells , Liver/immunology , Liver/pathology , Liver Neoplasms/immunology , Liver Neoplasms/pathology , Lymphocytes/immunology , TNF-Related Apoptosis-Inducing Ligand
6.
Chinese Journal of Oncology ; (12): 502-504, 2005.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-358589

ABSTRACT

<p><b>OBJECTIVE</b>To evaluate the effect and acute toxicity of concurrent radio-chemotherapy, by NVB and DDP, plus concurrent radiotherapy in comparison with chemotherapy alone in the treatment of inoperable locally advanced non-small-cell lung cancer (LANSCLC).</p><p><b>METHODS</b>Sixty-four patients with inoperable LANSCLC were randomly divided by envelope method into two groups: concurrent radio-chemotherapy group (n = 33) and conventional chemotherapy group (n = 31). The patients in conventional chemotherapy group were treated by NP regimen (NVB + DDP): NVB 25 mg/m(2), d1, 8 and DDP 25-30 mg/m(2) d1-3. In the radio-chemotherapy group by NP regimen plus conventional radiotherapy by (60)Co: 64-68 Gy/2 Gy x 5/w x 6-7w.</p><p><b>RESULTS</b>All patients completed the treatment schedule. The overall response rate (CR + PR) in the radio-chemotherapy group was significantly higher than that in the conventional chemotherapy group: 81.8% vs 45.2%, (P < 0.01) with 1- and 2-year survival rates of 69.7% vs 38.7% (P < 0.05) and 39.4% vs 16.1% (P < 0.05). without any significant difference in the acute toxicity between two groups (P > 0.05).</p><p><b>CONCLUSION</b>Compared with conventional chemotherapy (NVP and DDP), concurrent radio-chemotherapy (NVP and DDP plus concurrent radiotherapy) is more effective and tolerable for the inoperable locally advanced non-small-cell lung cancer.</p>


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Antineoplastic Combined Chemotherapy Protocols , Therapeutic Uses , Carcinoma, Non-Small-Cell Lung , Drug Therapy , Radiotherapy , Cisplatin , Combined Modality Therapy , Lung Neoplasms , Drug Therapy , Radiotherapy , Radiation-Sensitizing Agents , Vinblastine
7.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-358042

ABSTRACT

<p><b>OBJECTIVE</b>To prepare OANO-1 microspheres and test their release in vitro.</p><p><b>METHOD</b>OANO-1 microspheres were made by W/O/W-liquid drying process. The surface morphology of the microspheres was observed by SEM. The mean diameter and the size distribution of microspheres, the drug loading and the incorporation efficiency were examined. The release of OANO-1 microspheres in vitro was examined by small cup method. The accumulated release percent of OANO-1 microspheres was examined.</p><p><b>RESULT</b>The OANO-1 microspheres were regular in their morphology. The average particle size was 8.59 microm with over 90% of the microspheres being in the range of 1-12 microm. The drug loading and the incorporation efficiency were 48.39% and 19.32% respectively. The accumulated release percent of OANO-1 microspheres was 78.4% after 108 h. The release half-life t1/2 was 40.8 h and Higuchi equation was Y = 0.1326 X - 0.4782, r = 0.9951.</p><p><b>CONCLUSION</b>The preparation of OANO-1 microspheres was well. The release in vitro of OANO-1 microspheres showed significant sustained release.</p>


Subject(s)
Angelica sinensis , Chemistry , Delayed-Action Preparations , Drug Carriers , Drug Combinations , Drug Compounding , Methods , Drugs, Chinese Herbal , Chemistry , Epimedium , Chemistry , Ficusin , Furocoumarins , Microspheres , Particle Size , Plants, Medicinal , Chemistry , Psoralea , Chemistry
8.
Int Immunopharmacol ; 4(14): 1805-16, 2004 Dec 20.
Article in English | MEDLINE | ID: mdl-15531296

ABSTRACT

This study was designed to assess the in vitro effects of morphine on the lymphocytes infected with SIV. CEM x174 cells were cotreated with morphine and simian immunodeficiency virus (SIVmac239). Cells were cultured for 96 h and the effects of morphine on the viability of infected cells were determined. At the concentration of 1 micromol/l, morphine could inhibit the proliferation of CEM x174 cells at the culture of 72 h. The stronger effect was observed in the case of viral infection. During 72 h SIV loading, the cells were accumulated in S phase in all SIV infected groups. The S arrest was observed in every experimental group and statistically different from normal groups (P<0.05). The results from annexin V binding assay showed that SIV infection resulted in a lower proportion of vital cells and higher mortality compared with corresponding control (P<0.01). Morphine failed to induce detectable alteration in the cell cycle profile of viral infected cells. Western blotting showed that the synthesis of intracellular p53 and bax protein was gradually up-regulated in the virus-loading period of 72 h. Naloxone had an apparent additive rather than antagonistic effect on the morphine-associated enhancement of bax expression. The ratio of bax/bcl-2 proteins appeared to tilt the balance toward apoptosis. At 72 h of infection, 1 micromol/l of morphine significantly elevated the level of caspase-3. These results indicated that the alteration in the balance of intracellular apoptotic and anti-apoptotic elements is one of the reasons of accelerated progression of acquired immunodeficiency syndrome (AIDS) by opioids abuse.


Subject(s)
Apoptosis/drug effects , Morphine/pharmacology , Narcotics/pharmacology , Simian Acquired Immunodeficiency Syndrome/pathology , Annexin A5/metabolism , Blotting, Western , Cell Cycle/drug effects , Cell Line , Cell Survival/drug effects , Humans , Hybrid Cells , Lymphotoxin-alpha/biosynthesis , Lymphotoxin-alpha/genetics , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction , Tetrazolium Salts , Thiazoles
9.
Toxicol In Vitro ; 18(4): 449-56, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15130602

ABSTRACT

Progression of HIV infections to AIDS is a complex process and it differs considerably among individuals infected with HIV, influenced by both genetic and environmental factors. Opiates have been implicated to be a cofactor in HIV infections leading to AIDS. However, little is known about the molecular mechanisms involved in the effects of opioids on HIV infected immune cells. Cell cycle analysis was carried out by flow cytometry, the phosphorylation of mitogen-activated protein kinases ERK1 and ERK2 was detected by Western blotting assay, and changes of calcium concentration were monitored by scanning intracellular fluorescence intensity. In response to the treatment with morphine, SIV-infected cells were accumulated in G1 phase. Morphine increased the content of intracellular calcium in a time-dependent manner. In addition, morphine also elevated the levels of PKC activity and phosphorylated ERK1/2. Therefore, it is implicated that the calcium-PKC-MAPK cascade is involved in morphine-prolonged survival of SIV-infected cells in the early stages of virus infection.


Subject(s)
Acquired Immunodeficiency Syndrome/physiopathology , B-Lymphocytes/physiology , Cell Cycle/drug effects , Cell Survival , HIV Infections/physiopathology , Morphine/pharmacology , Narcotics/pharmacology , T-Lymphocytes/physiology , Apoptosis , B-Lymphocytes/virology , Blotting, Western , Cell Culture Techniques , Flow Cytometry , Humans , Signal Transduction , Simian Immunodeficiency Virus/pathogenicity , T-Lymphocytes/virology
10.
World J Gastroenterol ; 10(6): 819-24, 2004 Mar 15.
Article in English | MEDLINE | ID: mdl-15040024

ABSTRACT

AIM: To investigate the molecular mechanism of alpha-fetoprotein (AFP) on regulating the proliferation of human hepatocellular carcinoma cells. METHODS: Alpha-fetoprotein purified from human umbilical blood was added to cultured human hepatocellular carcinoma Bel 7402 cells in vitro for various treatment periods. The expression of c-fos, c-jun, and N-ras mRNA involved in proliferation and differentiation of cells was analyzed by Northern blot, and the expression of mutative p53 and p21(ras) proteins was determined by Western blot. RESULTS: The results showed that AFP (20 mg/L) stimulated mRNA expression of these oncogenes in Bel 7402 cells. The expression of c-fos mRNA increased by 51.1%, 60.9%, 96.0%, and 25.5% at 2, 6, 12, and 24 h, respectively. The expression of c-jun and N-ras mRNA reached to the maximum which increased by 81.3% and 59.9% as compared with the control after 6 h and 24 h incubation with AFP, respectively. Western blot assay also demonstrated that AFP promoted the expression of mutative p53 and p21(ras) proteins, and the increased rate of those proteins was 13.0%, 39.9%, and 70.9%, as well as 35.2%, 102.6%, and 46.8% at 6, 12, and 24 h, respectively, as compared with the control. Both human serum albumin (the same dosage as AFP) and monoclonal anti-AFP antibody failed to stimulate the expression of these oncogenes, but anti-AFP antibody could block the functions of AFP. CONCLUSION: The data indicate that AFP can stimulate the expression of some oncogenes to enhance the proliferation of human hepatocellular carcinoma Bel 7402 cells.


Subject(s)
Carcinoma, Hepatocellular/genetics , Gene Expression/drug effects , Liver Neoplasms/genetics , Oncogenes , alpha-Fetoproteins/pharmacology , Cell Line, Tumor , Humans
11.
Int Immunopharmacol ; 4(1): 79-90, 2004 Jan.
Article in English | MEDLINE | ID: mdl-14975362

ABSTRACT

Methionine enkephalin, the endogenous opioid peptide, has a diversity of effects on the immune system. Although the biological effects of the pentapeptide have been well documented, little is known about the intracellular events involved in the effects of opioids on human immunodeficiency virus (HIV) infected immune cells. In the present investigation, the possible mechanism of apoptosis alleviated by exposure of methionine enkephalin at 1 micromol/l to CEM x 174 cells, the hybrid lymphocytes, infected with simian immunodeficiency virus (SIV) in vitro is elucidated. Apoptosis and cell cycle analysis is carried out by flow cytometry, the phosphorylation of mitogen-activated protein kinases (MAPK) ERK1 and ERK2 is detected by Western blotting assay, and changes of calcium concentration were analyzed using the calcium-sensitive dye Fluo-3 AM. The results exhibit that methionine enkephalin at the concentrations of 1 micromol/l increase remarkably the proportion of vital cells and decrease the apoptotic cells based on annexin V binding assay. In response to the treatment with methionine enkephalin, SIV-infected cells display a prolonged survival and are accumulated in G1 phase. Methionine enkephalin increase obviously the content of intracellular calcium in normal cells within 1-2 min and maintains a high level within monitoring time. However, the intracellular calcium reaches the highest level at 1 min and subsequently decline to background in SIV infected group. In addition, methionine enkephalin also elevates the levels of protein kinase C (PKC) activity and phosphorylated extracellular signal-regulated kinase (ERK) 1/2. It is proposed that calcium-PKC-MAPK cascade is involved in methionine enkephalin-prolonged survival of SIV-infected cells in the early stages of virus infection. The results provide a further evidence for potential use of methionine enkephalin on the therapy of Acquired Immunodeficiency Syndrome (AIDS).


Subject(s)
Enkephalin, Methionine/physiology , Lymphocytes/virology , Signal Transduction , Simian Immunodeficiency Virus/drug effects , Apoptosis/drug effects , Blotting, Western , Calcium/metabolism , Cell Cycle/drug effects , Cell Line , Cell Survival/drug effects , Enkephalin, Methionine/pharmacology , Flow Cytometry , Humans , Lymphocytes/cytology , Lymphocytes/immunology , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation , Protein Kinase C/metabolism , Simian Immunodeficiency Virus/physiology
12.
World J Gastroenterol ; 9(1): 169-73, 2003 Jan.
Article in English | MEDLINE | ID: mdl-12508376

ABSTRACT

AIM: To investigate experimentally the effects of methionine enkephalin on signal transduction of mouse myeloma NS-1 cells. METHODS: The antigen determinate of delta opioid receptor was designed in this lab and the polypeptide fragment of antigen determinate with 12 amino acids residues was synthesized. Monoclonal antibody against this peptide fragment was prepared. Proliferation of Mouse NS-1 cells treated with methionine enkephalin of 1 x 10(-6) mol x L(-1) was observed. The activities of protein kinase A (PKA) and protein kinase C (PKC) were measured and thereby the mechanism of effect of methionine enkephalin was postulated. RESULTS: The results demonstrated that methionine enkephalin could enhance the proliferation of NS-1 cells and the effect of methionine enkephalin could be particularly blocked by monoclonal antibody. The activity of PKA was increased in both cytosol and cell membrane. With reference to PKC, the intracellular activity of PKC in NS-1 cells was elevated at 1 x 10(-7) mol x L(-1) and then declined gradually as the concentration of methionine enkephalin was raised. The effects of methionine enkephalin might be reversed by both naloxone and monoclonal antibody. CONCLUSION: Coupled with the findings, it indicates that the signal transduction systems via PKA and PKC are involved in the effects of methionine enkephalin by binding with the traditional opioid receptors,and therefore resulting in different biological effects.


Subject(s)
Cytokines , Enkephalin, Methionine/pharmacology , Signal Transduction/drug effects , Animals , Antibodies, Monoclonal/immunology , Cyclic AMP-Dependent Protein Kinases/metabolism , Enkephalin, Methionine/metabolism , Mice , Mice, Inbred BALB C , Naloxone/pharmacology , Narcotic Antagonists/pharmacology , Protein Kinase C/metabolism , Receptors, Opioid, delta/genetics , Receptors, Opioid, delta/immunology , Receptors, Opioid, delta/metabolism , Tumor Cells, Cultured
13.
Article in English | MEDLINE | ID: mdl-12417922

ABSTRACT

A lot of investigations showed that alpha-fetoprotein(AFP) could regulate the proliferation of tumors or neoplastic cells. In order to study the enhancement of this function, AFP was extracted from human cord blood serum and was allowed to act on HeLa cell in vitro. The cellular proliferation was investigated by using the MTT assay and the [(3)H]-incorporation, and the cell cycle was analysed with flow cytometry. Radioactive immunosorbent assay was utilized to detect cAMP accumulation, protein kinase A activity and confocal microscopy was used f or scanning intracellular calcium. The expression of mutant p53 and p21(ras) protein were analyzed by Western blotting. Our results showed that AFP (>10 mg/L ) had strong effect of enhancement on the proliferation of HeLa cells; AFP (20 mg /L) could significantly increase the concentration of cAMP (300%), Ca(2+) (154.9%) and protein kinase A activity (100%). It was also shown that the expression of mutant p53 and p21(ras) protein of HeLa cells were enhanced after t he treatment with AFP (20 mg/L) for 24 hours. Compared with control, the expression of mutant p53 protein was increased by 81.1% (24 h), p21(ras) protein was increased by 96.2% (24 h) respectively; but the monoclonal antibody to AFP blocked these functions of AFP. In conclusion, AFP enhanced the proliferation of HeLa cells; AFP may regulate the growth of the cells by influencing the transmembrane signal pathway and enhancing the expression of the oncogenes.


Subject(s)
Cell Cycle/drug effects , alpha-Fetoproteins/pharmacology , Calcium/metabolism , Cell Division/drug effects , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , HeLa Cells , Humans , Microscopy, Confocal , Mutation , Proto-Oncogene Proteins p21(ras)/drug effects , Proto-Oncogene Proteins p21(ras)/metabolism , Tumor Suppressor Protein p53/drug effects , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
14.
Cell Res ; 12(2): 151-6, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12118941

ABSTRACT

AIM: The existence and properties of alpha-fetoprotein (AFP) receptor on the surface of NIH 3T3 cells and the effects of AFP on cellular signal transduction pathway were investigated. METHODS: The effect of AFP on the proliferation of NIH 3T3 cells was measured by incorporation of 3H-TdR. Receptor-binding assay of 125I-AFP was performed to detect the properties of AFP receptor in NIH 3T3 cells. The influences of AFP on the [cAMP]i and the activities of protein kinase A (PKA) were determined. Western blot was used to detect the change of K-ras P21 protein expression. RESULTS: The proliferation of NIH 3T3 cells treated with 0-80 mg/L of AFP was significantly enhanced. The Scatchard analysis indicated that there were two classes of binding sites with KD of 2.722 x 10(-9)M (Bmax=12810 sites per cell) and 8.931 x 10(-8)M (Bmax=119700 sites per cell) respectively. In the presence of AFP (20 mg/L), the content of cAMP and activities of PKA were significantly elevated . The level of K-ras P21 protein was upregulated by AFP at the concentration of 20 mg/L. The monoclonal antibody against AFP could reverse the effects of AFP on the cAMP content, PKA activity and the expression of K-ras p21 gene. CONCLUSION: The effect of AFP on the cell proliferation was achieved by binding its receptor to trigger the signal transduction pathway of cAMP-PKA and alter the expression of K- ras p21 gene.


Subject(s)
alpha-Fetoproteins/physiology , 3T3 Cells , Animals , Cell Division , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Dose-Response Relationship, Drug , Humans , Mice , Receptors, Peptide/metabolism , Signal Transduction , Time Factors , alpha-Fetoproteins/metabolism
15.
World J Gastroenterol ; 8(3): 469-75, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12046072

ABSTRACT

AIM: The goal of this study was to characterize the AFP receptor, its possible signal transduction pathway and its proliferative functions in human hepatoma cell line Bel 7402. METHODS: Cell proliferation enhanced by AFP was detected by MTT assay, 3H-thymidine incorporation and S-stage percentage of cell cycle analysis. With radioactive labeled 125I-AFP for receptor binding assay; cAMP accumulation, protein kinase A activity were detected by radioactive immunosorbent assay and the change of intracellular free calcium (Ca2+i) was monitored by scanning fluorescence intensity under TCS-NT confocal microscope. The expression of oncogenes N- ras, p 53, and p21( ras ) in the cultured cells in vitro were detected by Northern blotting and Western blotting respectively. RESULTS: It was demonstrated that AFP enhanced the proliferation of human hepatoma Bel 7402 cell in a dose dependent fashion as shown in MTT assay, (3)H-thymidine incorporation and S-phase percentage up to 2-fold. Two subtypes of AFP receptors were identified in the cells with Kds of 1.3 x 10(-9)mol.L(-1) and 9.9 x10(-8)mol. (-1)L respectively. Pretreatment of cells with AFP resulted in a significant increase (625%) in cAMP accumulation. The activity of protein kinase A activity were increased up to 37.5, 122.6, 73.7 and 61.2% at treatment time point 2, 6, 12 and 24 hours. The level of intracellular calcium were elevated after the treatment of alpha-fetoprotein and achieved to 204% at 4 min. The results also showed that AFP(20mg.L(-1)) could upregulate the expression of N- ras oncogenes and p 53 and p21( ras ) in Bel 7402 cells. In the later case,the alteration were 81.1%(12h) and 97.3%(12h) respectively compared with control. CONCLUSION: These results demonstrate that AFP is a potential growth factor to promote the proliferation of human hepatoma Bel 7402 cells. Its growth-regulatory effects are mediated by its specific plasma membrane receptors coupled with its transmembrane signaling transduction through the pathway of cAMP-PKA and intracellular calcium to regulate the expression of oncogenes.


Subject(s)
Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , alpha-Fetoproteins/pharmacology , Calcium/metabolism , Carcinoma, Hepatocellular/physiopathology , Cell Division/drug effects , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Humans , Liver Neoplasms/physiopathology , Receptors, Peptide/physiology , Signal Transduction/drug effects , Tumor Cells, Cultured
16.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-676469

ABSTRACT

0.05).The median survival time was 32 weeks in group A compared to 27 weeks in group B(P

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