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1.
Chinese Pharmacological Bulletin ; (12): 75-83, 2021.
Artigo em Chinês | WPRIM | ID: wpr-1014296

RESUMO

Aim To study the effect of proliferation and activation of vascular smooth muscle cells (VSMCs) induced by activated the complement alternative pathway and intervention. Methods Normal human plasma was specifically activated the complement alternative pathway by incubated with cobra venom factor (CVF). Exposed VSMCs to the activated complement products, the change of cell morphology and the cell viability were assayed by inverted phase contrast microscope and MTT method, respectively. The supernatant was assayed for expression of E-selectin, ICAM-1 and VCAM-1 by using ELISA reagent kits. The protein expression levels of p-NF-kB p65, NF-kB p65 and IKK were assayed by Western blot. The nucleus transcriptional activity of NF-ΚB p65 was tested by the dual luciferase reporter assay system. Pyrrolidine dithiocarbamate (PDTC) was used to intervene the proliferation and activation of VSMCs. Results VSMCs were activated and induced to proliferation after exposed to the products of activated complement alternative pathway. The expressions of E-selectin, VCAM-1 and ICAM-1 were up-regulated. The contents of ICAM-1 and VCAM-1 reached the peak at 6 h and the E-selectin increased significantly at 12 h. Meanwhile, the phosphorylation level of NF-ΚB p65, nucleus transcriptional activity of NF-ΚB p65 and the protein expression of IKK and N F - Κ B p65 increased. The above mentioned changes were clearly inhibited by PDTC. Conclusions The activated complement alternative pathway can initiate proliferation and activation of VSMCs, and its mechanism goes hand in hand with activation of N F - Κ B signaling pathway. PDTC, a specific inhibitor of N F - K B, can effectively inhibit the proliferation and activation of VSMCs.

2.
Chinese Pharmacological Bulletin ; (12): 23-27, 2018.
Artigo em Chinês | WPRIM | ID: wpr-664591

RESUMO

Aim To study the effect of cobra venom nerve growth factor ( NGF) on inducing the apoptosis of LX2 cells, the key cells of hepatic fibrosis , through Akt signaling pathway and its underlying mechanism .Methods CCK-8 method was used to detect the pro-liferation of LX2 cells at different concentrations of NGF and LY294002 .Flow cytometry was applied to detect the effect of NGF on the apoptosis of LX 2 cells. Western blot was used to study the effects of NGF and LY294002 respectively , and their combination on the p-Akt protein level .Results NGF could decrease the survival rate of LX2 cells, and the minimum effective concentration was 1mg· L-1; it increased the apopto-sis rate of LX2 cells within the rise of concentration un-der a certain of range and decreased the expression level of p-Akt, but it had no significant effect on the ex-pression of Akt .Conclusions NGF may promote the apoptosis of LX2 cells by inhibiting the activation of PI3K/Akt signaling pathway in a concentration-de-pendent manner .The study of the pathogenesis of liver fibrosis is significant for the clinical treatment of liver fibrosis.

3.
Chinese Pharmacological Bulletin ; (12): 988-993, 2018.
Artigo em Chinês | WPRIM | ID: wpr-705164

RESUMO

Aim To explore the protective effect and mechanism of icariin ( ICA ) on acute lung injury ( ALI) in mice induced by activation of the comple-ment alternative pathway. Methods 32 healthy KM mice were randomly divided into four groups: the nor-mal group, the model group, the PDTC group and the Icariin group, which received 7-day intragastric admin-istration respectively. Then cobra venom factor ( CVF) was used to activate specifically complement alternative pathway to induce acute lung injury in mice by intrave-nous injection. Myeloperoxidase ( MPO ) activity of lung homogenate, the cell count and the protein con- tent of bronchoalveolar lavage fluid ( BALF ) were measured. The concentration of IL-6, TNF-α, P-selec-tin and ICAM-1 in BALF and serum were determined by ELISA. The pathological change of lung tissue was observed by HE staining. The phosphorylation of NF-κB p65 in lung tissues was checked by immunohisto-chemistry. The effect of the transcriptional activity of NF-κB signal pathway in microvascular endothelial cells was measured by employing dual-luciferase re-porter assay system. Results ICA reduced MPO ac-tivity of lung homogenate, the cell count and the con-tent of IL-6, TNF-α, P-selectin in BALF obviously. The level of TNF-α, P-selectin and ICAM-1 in serum was decreased, the pulmonary inflammatory cell infil-tration was reduced, the phosphorylation of NF-κB p65 in lung was inhibited significantly and the transcrip-tional activity of NF-κB was also down-regulated. Con-clusion ICA can alleviate acute inflammatory re-sponse of ALI mice induced by activation of the com-plement alternative pathway. The mechanism may be highly related to the inhibition of inflammatory cell in-filtration in lung tissue, the down-regulation of phos-phorylation of NF-κB p65 and nuclear transcriptional activity.

4.
Chinese Pharmacological Bulletin ; (12): 1430-1435, 2017.
Artigo em Chinês | WPRIM | ID: wpr-614870

RESUMO

Aim To investigate the change of coagulation and fibrinolysis functions of human microvascular endothelial cells (HMEC) induced by activated complement alternative pathway and effect of pyrrolidine-dithiocarbamate (PDTC) and resveratrol (Res) on intervention.Methods Normal human serum was activated by cobra venom factor (CVF).After exposure of HMEC to activated complement for various time points, supernatant was removed and assayed for activities of hydrolysing chromogenic substrate and affecting activated partial thromboplastin time (APTT) and prothrombin time (PT).The cells exposed to activated complement were collected and washed, and then the cell suspension was assayed for activity of affecting coagulation function of normal plasma.Lastly, the coagulation and fibrinolysis functions of HMEC pretreated with PDTC and Res were also investigated after HMEC was exposed to activated complement alternative pathway.Results The hydrolysis activity of chromogenic substrate of supernatant was up-regulated significantly after HMEC exposed to activated complement alternative pathway.The supernatant induced APTT decreased significantly, and also shortened PT.The cell suspension of various time points induced APTT decreased significantly, and also shortened PT by suspension of 6 h time point.PDTC and Res failed to inhibit the up-regulation of the chromogenic hydrolysis activity, but Res showed significant intervention on decrease of APTT, and PDTC had better effect on inhibiting the decrease of PT than that of Res.Conclusion Activated complement alternative pathway can induce abnormality of coagulation and fibrinolysis functions of HMEC, and PDTC and Res can affect this change.

5.
Chinese Pharmacological Bulletin ; (12): 1521-1525,1526, 2016.
Artigo em Chinês | WPRIM | ID: wpr-605293

RESUMO

Aim To study the development of acute lung inflammation in mice induced by activation of the complement alternative pathway and the changes of the related indicators, and to provide an ideal pathological model of acute lung inflammation in mice for drug screening and intervention. Methods Cobra venom factor( CVF) was used to activate complement alterna-tive pathway of SPF Kunming mice by intravenous injection. According to different sampling time, the mice were divided into 15 min, 30 min, 1 h, 2 h, 6 h group, and the parallel PBS control groups were set at the same time. Lung coefficient, lung water content, myeloperoxidase ( MPO ) activity, BALF cell number and protein content were tested. The pathological changes of lung tissue were observed by HE staining. The concentration of IL-6 , TNF-α, P-selectin and ICAM-1 in bronchoalveolar lavage fluid ( BALF ) and serum were determined by ELISA. Results CVF caused pulmonary inflammatory cell infiltration in mice obviously. Compared with PBS groups, MPO activity of lung tissue, BALF cell and the protein concentration were significantly increased. The contents of IL-6, TNF-α, P-selectin in BALF and serum were in-creased, and the content of ICAM-1 in serum was also increased. The content of P-selectin in BALF reached the first peak at 30 min point, the content of IL-6 and TNF-α in BALF reached the first peak at 1 h point, but the indicators had no further changes at 2 h point, and all the indicators rose again at 6 h point. The lev-els of IL-6 and TNF-α in serum reached peak at 1 h point,then the content showed lower levels at the sub-sequent time points. The levels of P-selectin and ICAM-1 in serum increased along the time. Lung coef-ficient, lung water content and ICAM-1 of the BALF showed no significant alteration. Conclusion The ac-tivation of the complement alternative pathway can lead to acute lung inflammation in mice and the inflammato-ry response is the most obvious at 30 min to 1 h. The study could provide an ideal pathological model of a-cute lung inflammation in mice for drug screening and intervention.

6.
Chinese Pharmacological Bulletin ; (12): 1421-1425,1426, 2015.
Artigo em Chinês | WPRIM | ID: wpr-602529

RESUMO

Aim To investigate the effect of resveratrol ( Res) , PDTC and AG490 on adhesion molecules ex-pression induced by product of activated complement alternative pathway on human microvascular endothelial cells ( HMECs) and the possible mechanisms. Meth-ods HMECs were exposed to the product of comple-ment alternative pathway activation, then the superna-tant was removed to detect the concentration of malond-ialdehyde ( MDA ) with TBA method. ELISA method was used to detect the expression of soluble ICAM-1 , VCAM-1 ( and E-selectin) in the culture supernatant. Res, PDTC and AG490 with different concentrations were used to determine their effect on cell oxidation level and adhesion molecules expression. The phospho-rylation of NF-κB p65 was detected by Western blot, and the intervention of Res, PDTC and AG490 was as-sayed by the same way. Results The activation of complements alternative pathway resulted in the phos-phorylation of NF-κB p65 , and increased the concen-tration of MDA and up-regulated the expression of ICAM-1, VCAM-1 and E-selectin. Res reduced the concentration of MDA. Res, PDTC and AG490 inhibi-ted the phosphorylation of NF-κB p65 . Res and PDTC showed similar inhibition on expression of ICAM-1 and VCAM-1 , while exhibiting little effect on expression of E-selectin, and AG490 significantly inhibited the ex-pression of the above adhesion molecules. Conclusions Res, PDTC and AG490 could inhibit the expression of adhesion molecules induced by activated complement alternative pathway, the inhibition of NF-κB pathway activation was involved in their mechanism, and JAK2 may be a more important intervention target in regula-ting adhesion molecule expression.

7.
Chinese Journal of Hepatobiliary Surgery ; (12): 377-380, 2012.
Artigo em Chinês | WPRIM | ID: wpr-425693

RESUMO

ObjectiveTo investigate synergistic effect of donor livers blocked by recipient blood serum (RS) and cobra venom factor (CVF) treatment to inhibit hyperacute rejection (HAR) happened in liver xenotransplantation.MethodsThe SD rat blood serum was prepared for pre-perfusing the donor livers before experiment.24 pairs of guinea-pig (GP) and Sprague-Dawley (S.D.) rats were choiced respectively and pair-matched between GP donor and rat recipient randomly.Before transplantation,donor livers of GPs were pre-perfused by 0.5% SD rat serum.Paired animals were divided into 4 groups randomly such as donor liver perfused by RS,recipient treated by CVF,RS+ CVF performed and Ringer solution as a control.The orthotopic liver xenotransplantations was performed with two-cuff technique.The survival time and liver function of recipients,morphological and pathological changes of rat livers were observed.ResultsThere was no piebaldism change on the recipient liver from experimental group.The survival time of recipients from RS+CVF group [(161.5±30.9) min]was longer than that of control[(45.2 ± 13.9) min] and CVF[(125.2 ± 25.5) min] or RS groups [(88.1±19.7) min] (P<0.05).The ALT in serum of recipients from RS+CVF [(63.2±13.9)U/L]was lower than that from congtrol group [(126.1±23.3)U/L](P<0.01) and CVF group [(79.9±18.1)U/L](P<0.05) or RS group [(106.1±19.3)U/L](P<0.01) The histological damages including thrombosis,interstitial bleeding and edema of recipient liver from RS+CVF group were alleviated markebly than that of other groups (P<0.05).ConclusionThere was a synergistic effect to inhibit HAR happened in liver xenotransplantation by blocking the donor liver with recipient blood serum and CVF treatment significantly.

8.
J. venom. anim. toxins incl. trop. dis ; 17(4): 451-459, 2011. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: lil-623508

RESUMO

The lethal and enzymatic activities of venom from Naja sumatrana (Equatorial spitting cobra) were determined and compared to venoms from three other Southeast Asian cobras (Naja sputatrix, Naja siamensis and Naja kaouthia). All four venoms exhibited the common characteristic enzymatic activities of Asiatic cobra venoms: low protease, phosphodiesterase, alkaline phosphomonoesterase and L-amino acid oxidase activities, moderately high acetylcholinesterase and hyaluronidase activities and high phospholipase A2. Fractionation of N. sumatrana venom by Resource® S cation exchange chromatography (GE Healthcare, USA) yielded nine major protein peaks, with all except the acidic protein peak being lethal to mice. Most of the protein peaks exhibit enzymatic activities, and L-amino acid oxidase, alkaline phosphomonoesterase, acetylcholinesterase, 5'-nucleotidase and hyaluronidase exist in multiple forms. Comparison of the Resource® S chromatograms of the four cobra venoms clearly indicates that the protein composition of N. sumatrana venom is distinct from venoms of the other two spitting cobras, N. sputatrix (Javan spitting cobra) and N. siamensis (Indochinese spitting cobra). The results support the revised systematics of the Asiatic cobra based on multivariate analysis of morphological characters. The three spitting cobra venoms exhibit two common features: the presence of basic, potentially pharmacologically active phospholipases A2 and a high content of polypeptide cardiotoxin, suggesting that the pathophysiological actions of the three spitting cobra venoms may be similar.(AU)


Assuntos
Fenômenos Bioquímicos , Cromatografia , Venenos Elapídicos , Cardiotoxinas , Elapidae
9.
Chinese Journal of Biochemical Pharmaceutics ; (6): 361-364, 2009.
Artigo em Chinês | WPRIM | ID: wpr-405072

RESUMO

Purpose To study the effect of China cobra venom active factor(CCVAF) from China cobra venom on endothelial cells and its mechanism.Methods MTT experiment was adopted to evaluate the effect of CCVAF on bovine arteria pulmonalis vascular endothelial cells(BAVEC).The Eosin-Coomassie brillient blue and rhodamine-phalloidin method was used for actin cytoskeleton.Flow cytometry for [Ca~(2+)]_i and spectrophotometry were used for lactate dehydrogenase(LDH) and nitrogen oxide(NO) levels in cell culture supernatant.Results CCVAF(0.625-20 μg/mL) inhibited the proliferation of BAVEC in dose-dependent manner,and IC50 of CCVAF on BAVEC was 2.45 μg/mL. After CCVAF and BAVEC coincubation, it was showed that regression of intercellular conjunctions and disorder of F-actin distribution occurred. The content of [Ca~(2+)]_i, [LDH] and [NO] increased respectively.Conclusion CCVAF can inhibit BAVEC proliferation and it maybe associated with the change of cytoskeleton and increasing of [Ca~(2+)]_i,[LDH] aod [NO].

10.
Chinese Journal of Microbiology and Immunology ; (12): 356-360, 2009.
Artigo em Chinês | WPRIM | ID: wpr-381063

RESUMO

Objective To prepare the bivalent immunoglobulin yolk (lgY) against eobra and viper venom and to detect its activities as the foundation for production and application of polyvalent . Methods The venom of Naja atra Cantor and Daboia russellii siamensis injected alternately into the leghorn hen. Biva-lent lgY was extraeted by water dilution. The biological activity of bivalent lgY were deteeted in several as-pects, sueh as the potency ( by indireet ELISA assay), the cross immunity ( by double immunodiffusion), the membrane lysis activity ( by experiments of vitelline membrane lysis) and 50% lethal activity ( LD50 ). Results Bivalent IgY was extracted from eggs yolk in 28-42 days after the first immunization. The titers of bivalent lgY against cobra and viper venom were 1:12 800 and 1: 6400. The cross immunologic reactions of bivalent IgY were found obviously with six kinds of snake venoms from Elapinae and Viperinae. There were not immunologic precipitation lines between bivalent IgY and four kinds of snake venoms from Crotalinae. Bi- valent lgY obviously deereased the vitelline membrane lysis activity of cobra and viper venom and prolonged the average survival time of mice with cobra or viper envenomation (P < 0.05). Moreover, with the same dose of bivalent IgY, the survival rate of mice with cobra venom envenomation was higher than those with vi-per venom envenomation. Conclusion Bivalent lgY could signifieantly neutralize biologieal activities of co-bra and viper venom, protect animals with cobra or viper envenomation.

11.
Journal of the Korean Surgical Society ; : 287-295, 2008.
Artigo em Coreano | WPRIM | ID: wpr-77804

RESUMO

PURPOSE: We designed a pig to canine liver xenotransplantation model to study the diverse immunologic and hemodynamic consequences that follow xenotransplantation and hyperacute rejection. METHODS: The animals were divided into two groups: the cobra venom factor and Gadolinium chloride treatment group (CVF+Gd group) (3 cases) and the control group (3 cases). The donor pig's whole liver was harvested, and then the harvested pig's whole liver was transplanted into a dog after the dog underwent left hepatectomy. After reperfusion of the graft, blood samples were taken 20, 40 and 60 minutes after reperfusion, and the liver, lung and kidney tissues were taken 1 hour after reperfusion. RESULTS: In the control group, the grafts showed a patchy hypoperfused liver surface and it felt rubbery solid compared to the CVF+Gd group. The serum total protein, albumin, fibrinogen and platelets decreased abruptly and there were no significant differences between the two groups. The serum PT, PTT and FDP were increased in both groups and the CVF+Gd group showed a more obtuse slope than the control group. We could not find any intravascular pathologic changes on the microscopic findings of the graft. Only scant intravascular fibrin deposition was found. Hepatocellular vacuolization and sinusoidal dilatation were also found. There were patches of necrosis without any zonal distribution, intrasinusoidal neutrophil sequestration and interstitial hemorrhage. These findings were milder in the CVF+Gd group. CONCLUSION: The pig to canine partial auxiliary liver xenotransplantation model is feasible and it is a good model before starting to perform pig to primate liver xenotransplantation. In the CVF+Gd group, pathologic findings like patch hepatocyte necrosis etc. were less severe. As there were no corresponding vascular pathologic findings, these findings are not the direct effect of CVF and gadolinium treatment, and so other factors like Ischemia- reperfusion injury should be considered.


Assuntos
Animais , Cães , Humanos , Plaquetas , Venenos Elapídicos , Proteínas do Sistema Complemento , Dilatação , Fibrina , Fibrinogênio , Fluconazol , Formicinas , Gadolínio , Hemodinâmica , Hemorragia , Hepatectomia , Hepatócitos , Rim , Células de Kupffer , Fígado , Pulmão , Necrose , Neutrófilos , Primatas , Rejeição em Psicologia , Reperfusão , Traumatismo por Reperfusão , Ribonucleotídeos , Doadores de Tecidos , Transplante Heterólogo , Transplantes
12.
J. venom. anim. toxins incl. trop. dis ; 10(3): 219-241, 2004. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: lil-383134

RESUMO

We investigated the in vitro process of cell death caused by Egyptian cobra venom on primary human embryonic kidney (293T) and mouse myoblast (C2C12) cell lines. The aim of these studies was to provide further information about triggering cell death, and suggest methods for eliminating unwanted cells, such as tumour cells. Both cell lines were treated with 10, 20, and 50 m g/ml of Egyptian cobra (Naja haje) venom in serum free media (SFM) and incubated for 8 hours. Total activities of the lactate dehydrogenase (LDH) and creatine kinase (CK) released in the culture during venom incubation were used as an indicator of the venom in vitro cytotoxicity. Cell injury was morphologically recognized and apoptosis determined by a Fluorescing Apoptosis Detection System and confirmed by staining nuclear DNA with DAPI. Our data clearly demonstrated marked cytotoxic effects and acute cell injury for both cell lines. Release of LDH and CK into the culture media induced by the venom correlates well with the morphological changes and extent of cell death. Mostly, these consequences were time and dose-dependent in both cell lines. The results obtained from this study indicated that cobra venom cause cell death by two different mechanisms: necrosis and induction of apoptosis. The apoptotic mechanism, accompanied by cell necrosis, mediated cell destruction of both tested cell lines; however, necrosis was predominant in the C2C12 cell line while apoptosis, in 293T cells. This unusual form of cell death induced by cobra venom may represent a combination of apoptosis and necrosis within the same cell. This is a first-hand investigation showing the apoptotic effects of N. haje venom at the cellular level. However, the contribution of the apoptotic pathway may be dependent on concentration and/or time of exposure to snake venom.(AU)


Assuntos
Animais , Peçonhas , Técnicas In Vitro , Apoptose , Naja haje , Células Cultivadas , Citotoxicidade Imunológica
13.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-557578

RESUMO

Aim To discuss whether specific Egg yolk antibody(IgY) can be used for snake venom antigens detection.Methods Chickens(white Leghorn) were immunized with detoxicated king cobra venom by formaldehyde.Egg yolk antibody were isolated from egg yolk,and labeled with horse radish peroxidase(HRP).Snake venom antigens samples,including king cobra venom,cobra venom,bungrarus fasciatus venom,bungrarus multicinctus venom,agkistrodon actus venom and Guangdong viper venom,were detected using ELISA,and sensitivity,precision and specificity were tested,respectively.Results At about 32 ?g?L~(-1),the king cobra antigens were detected using the method;Linear relation was better(r=0.963) when the concentration of kingcobra venom was within 32~750?g?L~(-1).The method had good specificity and no cross reactivity was observed among the reagents and agkistrodon acutus guenther venom and vipera russelli siamensis smith venom;little cross reactivity was shown with bungarus multicinctus blyth venom and bungarus fasciatus chmeider venom;cross reactivity was obvious with cobra venom;the average intra-assay coefficient of variation(CV) was 1%~3%,and the inter-assay CV was within 8%.Conclusions The study indicates that IgY can be good reagents for snake venom antigens detecton,and the study provides foundation for the development of the diagnosis kits of snakebites.

14.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-557269

RESUMO

Cobra venom secretory phospholipase A_2 (sPLA_2) is an important component of cobra venom which has a variety of biological activities. Recent studies are mainly focusing on each pharmacological active component of venom, SPLA_2 is one of them. This review summarized the structure, purification and biological activities of cobra venom sPLA_2 with emphasizing its diverse pharmacological effects and toxicity. In addition, some mechanisms of actions of sPLA_2 and possible applications of sPLA_2 were also discussed.

15.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-555871

RESUMO

Aim To develop King cobra antivenom from the egg yolks of immunized hens,and study dynamic expression of IgY in egg yolks.Methods chickens(white Leghorn) were immunized with detoxicated King cobra venom by formaldehyde ,Egg yolk antibody (IgY) was isotated by thiophilic interaction chromatography and identified by SDS-PAGE. Activity of IgY was evaluated by enzyme-linked immunoserbent assay(ELISA) and Double immuodiffusion. Protein was measured using folin-lowry method. Results Specific antivenom could be detected in the yolk laid by the hens 9 d after immunization, At the 60th day after primary immunization ,ELISA titers reached 1∶ 100 000,and 97.5 mg IgY?ml -1 yolk was obtained from thiophilic interaction chromatography. IgY was highly specific, No cross reactivity was observed among IgY and agkistrodon acutus venom and vipera venom ;Little cross reactivity was shown with cobra genus venoms.Conclusion King cobra IgY was obtained and purified from the egg yolks of immunized hens,The dynamic expression of IgY was manitered during the course of immunization,Further investigation is needed.

16.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-554171

RESUMO

AIM To study the hemolyzation of a highly active anti complementary protein (cobra venom factor, CVF) isolated from the venom of Naja kaouthia distributed in the south of Yunnan Province, China. METHODS Guinea pig red blood cell and serum were employed to evaluate the hemolyzation of this anticomplement factor, and the effects of temperature, pH, various bivalent mental ions and EDTA on its hemolyzation were investigated. RESULTS This anticomplement factor possessed hemolytic activity of 1 391 kU?g -1 protein. It showed high stability to heat, alkalinity and acidity. Ca 2+ , Mg 2+ , Mn 2+ promoted the hemolyzation of this anticomplement factor at 1, 2 and 5 mmol?L -1 . Zn 2+ , Co 2+ also promoted the hemolyzation of this anticomplement factor at 1 and 2 mmol?L -1 , but inhibited the hemolyzation at 5 mmol?L -1 . Cu 2+ strongly inhibited the hemolyzation at 1, 2 and 5 mmol?L -1 . EDTA also strongly inhibited the hemolyzation of this anticomplement factor. CONCL- USION The anticomplement factor showed hemolytic activity. This ability could be influenced by bivalent metal ions and EDTA, but rather stable when temperature or pH value changed.

17.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-566304

RESUMO

Aim To investigate the inhibitory effect of atrase B on human platelet aggregation induced by activated complement.Methods By employing CVF to activate complement,the effect of atrase B on gel filtered platelet aggregation induced by activated complement was measured by turbidimetry and the expression of P-selectin and GPⅡb/Ⅲa on platelet membrane were detected by flow cytometry.Results Atrase B inhibited platelet aggregation and the expression of P-selectin and GPⅡb/Ⅲa on platelet membrane induced by activated complement.Conclusion Anticomplementary protein atrase B from Naja atra venom can significantly inhibit platelet activation and aggregation induced by activated complement.

18.
Chinese Pharmacological Bulletin ; (12)2003.
Artigo em Chinês | WPRIM | ID: wpr-566154

RESUMO

Aim To investigate the effect of cobra venom metalloproteinase atrase A on human endothelial cell.Methods The effects of atrase A on the growth of HMEC were measured by MTT,SRB and morphological observation methods,respectively.After exposure to atrase A,IL-8,ICAM-1,MCP-1 and E-selectin released by HMEC were detected.Caspase-8 and caspase-3/7 were detected by fluorescent luminescence method.After intravenous injected atrase A to rats,the concentrations of ICAM-1,IL-8 and TNF-? in serum were measured.Results The results showed that atrase A(400,40 mg?L-1) significantly inhibited the growth of HMEC in low cell density.The microscopic examination revealed that atrase A detached the adherent HMEC.After exposure to atrase A,IL-8,ICAM-1 and MCP-1 released by HMEC were increased.Atrase A induced HMEC to express caspase-3/7 and caspase-8.After the administration of atrase A to rats,the concentrations of ICAM-1,IL-8 and TNF-? in serum were increased.There was no difference between the low-dose group and control group in our experiments.Conclusion Cobra venom metalloproteinase atrase A inhibits the growth of HMEC,and induces HMEC releasing inflammation mediators and apoptosis.

19.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1484817

RESUMO

Adenosine deaminase (ADA), histamine, and IgE are endogenously present in animals. Research from this laboratory reported decreased levels of these substances in organs of mice as a consequence of sub-lethal injection of Naja kaouthia venom. This research reports that decreased ADA, histamine, and IgE levels were prevented by specific treatment and prolonged recovery periods. Adult Balb/c mice injected IM with sub-lethal venom dose were divided into five groups. Group 1 were injected with PBS; Group 2 with anti-cobra venom; and Group 3 with lethal toxin neutralizing factor (LTNF). Groups 4 and 5 were treated with IM or oral synthetic LT-10. After 24 hours, mice were sacrificed and organ homogenates were assayed for ADA, histamine, and IgE. Group 1 showed substantial reduction in levels of these substances. It was revealed that decreased levels were prevented by treatment with anti-cobra venom, LTNF, and LT-10. In a second series of experiments, venom-injected mice were sacrificed after 3, 7, and 10 days and organs assayed for ADA, histamine, and IgE levels. The recovery period to homeostasis for ADA, histamine, and IgE was 7 to 10 days.

20.
Korean Journal of Immunology ; : 129-139, 1998.
Artigo em Coreano | WPRIM | ID: wpr-128248

RESUMO

Recently xenotransplantation has been thought as a final solution for the controi of donor organ shortage in allograft. In order to be a ciinicai entity, xenotransplantation has many obstacles such as hyperacute rejection and delayed xenogratt rejection as a potent immunologic reaction, zoonosis and ethical problems. We already reported the eariy immunoiogic events occuring soon after xenograft in animal model, in which natural antibody and complement have a crucial roie in rejection response. As a further step for the prolongation of graft survival, we used anticomplement agent (cobra venom factor, CVF) in the same model. Graft survival in discordant (guinea pig-to-rat) xenogratt was extended from 30.6 minutes to 2 days following singie injection of CVF, which showed similar pattern of rejection with the concordant xenogratt in terms of time of rejection response after grafting. In this setting antibody response in the blood did not show any difference between that of pre CVF and post CVF, even though IgM response was more pronounced than IgG. The complement activity in the blood showed marked suppression following CVF injection. Intragraft complement gene (C3 mRNA) expression in CVF injected discordant showed delayed response in a similar pattern like that of concordant xenograft. Interestingly enough intragraft anticomplement gene expression showed the simiiar pattern of response with the complement. From these results we can conclude that anticomplement agent (CVF) extended the graft survival in discordant xenograft upto the level of concordant xenograft by shifting the complement activation response from that of discordant to concordant xenograft.


Assuntos
Ratos , Animais
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