人参不同部位皂甙对衰老的人胚肺成纤维细胞酶活性的影响

应用细胞化学的定性定位,显微分光光度计定量分析的方法,测定人参不同部位皂甙对体外衰老的人胚肺成纤维细胞内乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、葡萄糖—6—磷酸脱氢酶(G—6—PDH)、葡萄糖—6—磷酸酶(G—6—Pase)、三磷酸腺苷酶(ATPase)、丙酮酸氧化酶(PVO)活性的影响。结果表明,人参根、果和茎叶皂甙(SRG,SFG,SSLG)都可以使衰老细胞内的LDH、SDH、G—6—PDH、G—6—Pase、ATPase和PVO活性增加。但对未衰老细胞的作用却不尽相同。

Occurrence of cGMP/nitric oxide-sensitive store-operated calcium entry in fibroblasts and its effect on matrix metalloproteinase secretion

AIM： To examine the existence of Nitric oxide/ cGMP sensitive store-operated Ca^2＋ entry in mouse fibroblast NIH/3T3 cells and its influence on matrix metalloproteinase （MMP） production and adhesion ability of fibroblasts. METHODS： NIH/3T3 cells were cultured. Confocal laser scanning microscopy was used to examine the existence of thapsigargin-induced store-operated Ca^2＋ entry in fibroblasts. Gelatin zymography and semiquantitative reverse transcriptase-polymerase chain reaction （RTPCR） were employed to detect the involvement of [Ca^2＋]i and NO/cGMP in MMP secretion. The involvement of NO/ cGMP-sensitive Ca^2＋ entry in adhesion was determined using matrigel-coated culture plates. RESULTS： 8-bromo-cGMP inhibited the thapsigargin-induced Ca^2＋ entry in 3T3 cells. The cGMP-induced inhibition was abolished by an inhibitor of protein kinase G, KT5823 （1μmol/L）. A similar effect on the Ca^2＋ entry was observed in 3T3 cells in response to a NO donor, （±）-S-nitroso-N-acetylpenicillamine （SNAP）. The inhibitory effect of SNAP on the thapsigargin-induced Ca^2＋ entry was also observed, indicating NO/cGMP-regulated Ca^2＋ entry in 3T3 cells. Results of gelatin zymography assay showed that addition of extracellular Ca^2＋ concentration induced MMP release and activation in a dose-dependent manner. RT-PCR also showed that cGMP and SNAP reduced the production of MMP mRNA in 3T3 cells. Experiments investigating adhesion potentials demonstrated that cGMP and SNAP could upgrade 3T3 cell attachment rate to the matrigel-coated culture plates.CONCLUSION： NO/cGMP sensitive store-operated Ca^2＋ entry occurs in fibroblasts, and attenuates their adhesion potentials through its influence on MMP secretion.

EFFECTS OF GENISTEIN ON INVASION AND MATRIX METALLOPROTEINASE ACTIVITIES OF HT1080 HUMAN FIBROSARCOMA CELLS

Effects of genistein on invasion and matrix metalloproteinase activities were investigated in HT1080 human sarcoma cells.Invasion of HT1080 cells through reconstituted basement membrane was inhibited when the cells were treated with 100 μ mol/L and 200 μ mol/L genistein.At the same concentrations,genistein not only suppressed latent forms of matrix metalloprotinese 2 and 9(MMP 2 and MMP 9) to convert into active forms,but also increase dramatically the tissue inhibitor of metalloproteinase(TIMP 1) mRNA contents and reverse the imbalance of MMPs and TIMPs.However,expressions of MMP 2 and MMP 9 were not significantly affected.Suppression of MMP activation and increase of TIMP 1 expression will decrease matrix degradation by MMPs,and consequently inhibit invasions of the cells.These results emphasized the existence of the imbalance between MMPs and TIMPs in tumor invasion and metastasis formation.The value of genistein as a drug for antiinvasion and anti metastasis chemotherapy was suggested.

A CHASE domain containing protein kinase OsCRL4, represents a new AtCRE1-like gene family in rice

AtCRE1 is known to be a cytokinin receptor in Arabidopsis. The AtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain of AtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice, OsCRL1a, OsCRL1b, OsCRL2, OsCRL3, and OsCRL4. OsCRL1a, OsCRL1b, OsCRL2 and OsCRL3 contain the four domains existing in CRE1, whereas OsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain. The authors cloned the encoding gene OsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice.

A POTENTIAL MECHANISM OF BREAKTHROUGH BLEEDING ASSOCIATED WITH PROGESTIN:INVOLVEMENT IN ALTERATION OF ENDOMETRIAL ENDOTHELIAL CELLS

Objective To explore the potential mechanism of breakthrough bleeding associated with progestin with in vitro methods.Methods The isolation and culture of human endometrial endothelial cells(HEECs)was performed with the method established in our laboratory.The content and activity of urokinase-type plasminogen activator(uPA)and the content of plasminogen activator inhibitor-1(PAI-1)in cell supernatants after incubated with different concentrations of progesterone(0-5 μmol/L)and 17β-estradiol(0,0.1,or 1 nmol/L)were measured by method of ELISA.Apoptosis rate of HEECs was measured by flow cytometry.Viable cell count was measured by MTT.Results The increased level of progesterone(0.5-5 μmol/L)combined with 17β-estradiol elevated content and activity of uPA while the production of PAI-1 remained unchanged.The apoptosis of HEECs was inhibited along with the increment of total viable cell counts at higher concentrations of progesterone with 17β-estradiol.Conclusion The inhibition of apoptosis and increased content and activity of uPA may contribute to the occurrence of irregular bleeding associated with progestin use to some extent.

Involvement of 90-kuD ribosomal S6 kinase in collagen type Ⅰ expression in rat hepatic fibrosis

AIM： To investigate the relationship between 90-kuD ribosomal $6 kinase （pg0RSK） and collagen type I expression during the development of hepatic fibrosis in vivo and in vitro.METHODS： Rat hepatic fibrosis was induced by intraperitoneal injection of dimethylnitrosamine. The protein expression and cell location of p90RSK and their relationship with collagen type I were determined by co-immunofluoresence and confocal microscopy.Subsequently, RNAi strategy was employed to silence p90RSK mRNA expression in HSC-T6, an activated hepatic stellate cell （HSC） line. The expression of collagen type I in HSC-T6 cells was assessed by Western blotting and real-time polymerase chainreaction. Furthermore, HSCs were transfected with expression vectors or RNAi constructs of p90RSK to increase or decrease the p90RSK expression, thencollagen type I promoter activity in the transfected HSCs was examined by reporter assay. Lastly HSC-T6 cells transfected with p90RSK siRNA was treated withor without platelet-derived growth factor （PDGF）-BB at a final concentration of 20μg/L and the cell growthwas determined by MTS conversion.RESULTS： In fibrotic liver tissues, p90RSK was over-expressed in activated HSCs and had a significantpositive correlation with collagen type I levels.In HSC-T6 cells transfected with RNAi targeted top90RSK, the expression of collagen type I was down-regulated （61.8% in mRNA, P 〈 0.01, 89.1% inprotein, P 〈 0.01）. However, collagen type ] promoteractivity was not increased with over-expression of p90RSK and not decreased with low expression either,compared with controls in the same cell line （P = 0.076）.Furthermore, p90RSK siRNA exerted the inhibitionof HSC proliferation, and also abolished the effect of PDGF on the HSC proliferation.CONCLUSION： p90RSK is over-expressed in activatedHSCs and involved in regulating the abnormalexpression of collagen type I through initiating theproliferation of HSCs.

Effect of trkA kinase inhibitor on apoptosis of human pterygium fibroblasts

Objective： The aim of this study was to investigate the growth inhibition effects and the mechanisms of trkA kinase inhibitor on human pterygium fibroblasts（HPF）. Methods： Three normal conjunctivas and eleven pterygiums were surgically collected, trkA and p75 was examined in different tissues by immunohistochemistry, trkA and p75 expression was detected in HPF by immumofluorescence method. After being treated with 10-80 nmol/L trkA kinase inhibitor for 24-96 h, the growth activities of HPF were studied by MTT colorimetry. Caspase-3 was inspected in HPF by spectrophotometric method. The apoptosis of HPF was detected by flow cytometry. Results： Expression of trkA and p75 was significantly observed in epithelium and fibroblast of pterygium tissues. Expression of trkAwas observed in epithelium and fibroblast of normal conjunc- tiva. Expression of p75 was only observed in epithelium of normal conjuncUva, trkA kinase inhibitor could effectively inhibit the growth of human pterygium fibroblasts in vitro in time and dose dependent manners. Caspase-3 expression was increased. The rates of apoptosis were 8.26%-29.62% （P 〈 0.01）. Conclusion： TrkA and p75 possibly participate in genesis and development of pterygium, trkA kinase inhibitor could induce apoptosis of human pterygium fibroblasts. Inducing apoptosis through changing the ratio of trkA and p75 in fibroblasts and up-regulate Caspase-3 was probably one of its molecular mechanisms.

Hirschsprung's disease:Is there a relationship between mast cells and nerve fibers?

AIM:To define the topography of mast cells and their numbers in cases of Hirschsprung's disease(HD)and non-HD,assess neural hypertrophy using imaging software and to study the relationship between mast cells and nerve fibers.METHODS:HE stained sections of 32 cases of chronic constipation in the age group of 0-14 years were reviewed for ganglion cells.AChE staining was performed on frozen sections of colonic and rectal biopsies.Based on their findings cases were divided into HD and non-HD and mast cells stained by toluidine blue were evaluated.Image analysis by computerized software was applied to S-100 stained sections for assessment of neural hypertrophy.RESULTS:Difference between number of mast cells in HD group(mean=36.44)and in non-HD group(mean =14.79)was statistically significant.Image analysis morphometry on S-100 stained sections served as a useful adjunct.The difference between number,size,and perimeter of the nerve fibers between HD and non-HD group was statistically significant.CONCLUSION:Mast cells are significantly increased in HD and their base line values are much higher in Indian children than that reported in Western literature.Their role in HD needs further research.Morphometry of S-100 stained nerve fibers is a useful adjunct to conventional methods for diagnosis of HD.

FGF-receptor substrate 2 functions as a molecular sensor ntegrating external regulatory signals into the FGF pathway

Fibroblast growth factor （FGF） receptor substrate 2a （FRS2α） is the main mediator of signaling in the FGF pathway. Recent studies have shown that mitogen-activated protein kinase （MAPK） phosphorylates serine and threonine residues in FRS2, negatively affecting FGF-induced tyrosine phosphorylation （PY） of FRS2. Several kinds of stimuli can induce serine/threonine phosphorylation （PS/T） of FRS2, indicating that FRS2 may be useful for studying crosstalk between growth factor signaling pathways. Here, we report that FGF-induced PY of FRS2 can be attenuated by EGF co-stimulation in PC12cells; this inhibitory effect could be completely reversed by U0126, an inhibitor of MEK. We further identified the ERK1/2-binding motif in FRS2 and generated FRS2-3KL, a mutant lacking MAPK binding and PT upon FGF and/or EGF stimulation. Unlike wild-type （WT） FRS2, FGF-induced PY of FRS2-3KL could not be inhibited by EGF co-stimulation, and FRS2-3KL-expressing PC12 cells exhibited more differentiating potential than FRS2-WT-expressing cells in response to FGF treatment. These results suggest that PS/T of FRS2 mediated by the FRS2-MAPK negative regulatory loop may function as a molecular switch integrating negative regulatory signals from other pathways into FGFR-generated signal transduction.

Alpha 1-antitrypsin and alpha 1-acid glycoprotein reduce the sensitivity of human dermal fibroblast to endotoxin

Objective: To test the hypothesis that acute phase reactants, such as alpha 1-antitrypsin and alpha 1-acid glycoprotein, could protect mammalian cells from further damage. Methods: Human dermal fibroblasts (5×10 4) were cultured with DMEM plus 10% FBS at 37℃ in a 5% CO 2 incubator. Different doses of LPS (lipopolysaccharide) and/or acute phase reactants were added. After 24 hours, the cultured supernatant was aspirated, the cells were washed, fixed and stained by methylene blue. The unbound stain was washed off. The stained cells were solubilized in 0.1 ml of 1% Triton X-100. The absorbance of each well was measured using an ELISA spectrophotometer. The concentration of LPS which decreased the absorbance to 70% of the control (LPS-free) cultures was defined as LD 30. Results: In order to achieve LD 30 in the presence of acute phase proteins, it was necessary to alter the LPS concentrations. The LD 30 of LPS treated with 0, 0.5, 2, 10 mg/ml antitrypsin and 0, 0.5, 2, 10 mg/ml glycoprotein was 5.4, 6.5, 7.6, 14.2 mg/ml and 5.2, 5.9, 6.9, 10.5 mg/ml, respectively. Statistically, with the treatment of more than 2 mg/ml antitrypsin or glycoprotein, LD 30 increased significantly. Conclusions: Our data show that fibroblasts are susceptible to the direct toxicity of LPS. Alpha 1-antitrypsin and alpha 1-acid glycoprotein can reduce the toxicity and/or increase the tolerance of mammalian cells to LPS.

Experimental Research of Electroacupuncture on ERK Phosphorylation in Rats of Hepatofibrosis

Objective： To observe the intervening effect of electroacupuncmre at Ganshu （BL 18） and Zusanli （ST 36） on ERK phosphorylation in rats of hepatofibrosis, and to explore the possible molecular mechanisms of electroacupunctre for hepatofibrosis. Methods： Forty male Wistar rats were randomly divided into normal group, model group, electroacupuncture group, and medicine group. Rats in the latter three groups were hypodermically injected with the mixture of olive oil and 30% carbon tetrachloride and drank tap water containing 10% alcohol to induce hepatic fibrosis model. Rats in the electroacupuncture group were stimulated at Zusanli （ST 36） and Ganshu （BL 18） by electroacupuncture, and rats in the medicine group were treated with Colchicine. The collagen hyperplasia of rats＇ hepatic tissue was observed by Sirius Red staining, and protein expression of ERK and phosphorylated ERK （P-ERK） were observed by Western Blot. Results： Compared with those in the normal group, collagen deposition in hepatic tissue obviously increased in the model group, and P-ERK protein expression was also up-regulated obviously （P〈0.01）. Compared with those in the model group, collagen deposition in hepatic tissue decreased in the electroacupuncmre and medicine groups, and P-ERK protein expressed was down-regulated （P〈0.01）. The difference between the electroacupuncture and medicine groups had no significance. Conclusion： Electroacupuncture can prevent or delay the development of hepatic fibrosis in rats by down-regulating the protein expression of P-ERK to block MAPK/ERK signal pathway and to suppress the synthesis of extracellular matrix.

Qingnaoyizhi decoction suppresses the formation of glial fibrillary acidic protein-positive cells in cultured neural stem cells by inhibiting the Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway

OBJECTIVE: Inactivation of the Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3) signaling axis plays a crucial role in determining the fate of neural stem cells(NSCs).Qingnaoyizhi decoction(QNYZD) has been used for the treatment of vascular dementia and has shown to improve synaptic remodeling. The aim of this study was to evaluate the effect of cerebrospinal fluid(CSF) containing QNYZD(CSF-QNYZD) on the differentiation of cultured NSCs and the involvement of the JAK2/STAT3 pathway.METHODS: The protein expression levels of glial fibrillary acidic protein(GFAP), tubulin, drosophila mothers against decapentaplegic protein(SMAD-1), STAT3, and phosphorylated-STAT3 were detected by western immunoblot analysis in the groups: control, CSF, JAK/STAT inhibitor(AG490),CSF-QNYZD, and CSF-XDZ(CSF-Xidezhen). The differentiation of NSCs was determined by immunofluorescence staining. The proliferation of NSCs was measured using the Cell Counting Kit-8 proliferation assay.RESULTS: Compared with the control group,CSF-QNYZD and AG490 significantly increased the number and expression of tubulin-positive cells, reduced the number and expression of GFAP-positive cells, and down-regulated the expression of p-STAT3. However, CSF-QNYZD also decreased the expression of SMAD-1 and STAT3.CONCLUSION: Enhanced neuronal differentiation may be associated with the down-regulation of glial differentiation instead of promoting proliferationin treated NSCs. Furthermore, QNYZD may play a direct role in suppressing the formation of GFAP-positive cells and enhancing neuronal differentiation by inhibiting JAK2/STAT3 activation. Overall, these results provide insights into the possible mechanism underlying QNYZD-mediated neurogenesis.

Regulatory Action of Charred Gossamer Urocteae on the Functions of Mouse Oral Fibroblasts

Objective： To explore the influence of charred Gossamer urocteae （CGU） on the functions of primary cultured mouse oral fibroblasts and reveal its mechanism in wound healing. Methods： CGU was extracted with different solvents and ethanol extract （EE）, ethyl acetate fraction （EF）, n-butanol fraction （BF） and aqueous fraction （AF） were obtained. The effects of different fractions on the proliferation, matrix metaUoproteinase-2,9 （MMP-2,9） activities, synthesis of collagen and tissue inhibitor of metalloproteinase 1 （TIMP-1） in the mouse oral fibroblasts were determined by MTT, gelatin zymography, chloramine-T method, and enzyme-linked immunosorbent assay （ELISA） respectively. Results： EE, EF and BF at high concentrations could significantly inhibit proliferation of fibroblasts （P〈0.05 or P〈0.01）, and at low concentrations EF and BF could promote proliferation of fibroblasts, and BF and AF could significantly inhibit collagen synthesis （P〈0.05 or P〈0.01）. EE, EF and AF at high concentrations could significantly increase the MMP-9 activity, and BF and AF could significantly inhibit synthesis of TIMP-1. Conclusion： CGU at high concentrations can inhibit the proliferations of fibroblasts and synthesis of collagen, and in healing of wound, CGU at high concentrations possibly has the functions of anti-fibrosis and anti-scar, and the mechanism to promote degradation of collagen is possibly related to the increase in MMP-9 activity and the inhibition of TIMP-1 synthesis.