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1.
The immunomodulator AS101 has recently been found to have radioprotective properties when injected prior to sublethal and lethal doses of irradiation. In addition, this compound was found to protect mice from hemopoietic damage caused by sublethal doses of cyclophosphamide (CYP) and to increase the rate of survival of mice treated with lethal doses of CYP. AS101 was previously shown to exert a synergistic effect with the PKC-inducer bryostatin in cytokine secretion in vitro. The present studies were designed to evaluate the effects of in vivo combined treatment with AS101 and bryostatin on bone marrow and spleen cellularity and on the number of committed progenitors in the bone marrow at various points of time after their treatment with a sublethal dose of CYP or irradiation. In addition, the combined effect was tested on the survival of mice irradiated with a lethal dose of irradiation. Our data show the presence of synergism which greatly enhances the number of bone marrow and spleen cells 48 hr and 9 days after CYP treatment or irradiation. The combined effect was also demonstrated when bone marrow colony-forming units granulocyte-macrophage (CFU-GM) progenitor cells were evaluated. Moreover, AS101 and bryostatin synergized in their protective effects against lethal damages of irradiation. These results strongly suggest that bryostatin, which lacks tumor-promoting activity, is a particularly good candidate in combination with AS101 for treatment in vivo in counteracting chemotherapy- or radiation-induced hematopoietic suppression or in generally improving the restoration of immune response under conditions involving immune or hemopoietic damage.  相似文献   

2.
Glucan effect on the survival of mice after radiation exposure   总被引:1,自引:0,他引:1  
The effect of glucan (beta-1,3-polyglucose) was investigated on the radiation-induced damage to the system of non-specific immunity in mice. A positive influence of glucan administered before exposure to a dose of 200 R was observed on the following parameters of postradiation regeneration: while blood cell count, due mainly to increased granulocyte count, increased per cent of peroxidase-positive cells in bone marrow, increased mass and cellularity of the spleen, in relation to the group of the animals not receiving the preparation. Administration of glucan 5 days before exposure to 650 R of X-rays prolonged the mean survival time. Administration of the preparation after exposure to radiation had no significant effect on the survival time of mice.  相似文献   

3.
目的:探讨唐古特大黄多糖组分1(RTP1)对急性电离辐射损伤小鼠的保护作用。方法:采用昆明种小鼠,随机分为5组:正常对照组(Normal Control,NC)、辐射对照组(Irradiation Control,IC)以及RTP1低剂量组(200 mg/kg)、中(400 mg/kg)和高剂量组(800 mg/kg),采用灌胃给药方式,连续14 d,NC组和IC组则给予等量的生理盐水,第14 d除NC组外,各组小鼠均接受2.0 Gy/只60Coγ射线照射1次,照射后24 h,检测小鼠胸腺和脾脏指数,测定肝脏超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活性及丙二酰二醛(MDA)水平以及小鼠外周血象和骨髓嗜多染红细胞(PCE)微核数。结果:RTP1能够升高小鼠的胸腺、脾脏指数,增加肝脏SOD和GSH-Px活性,降低MDA水平,升高外周血中白细胞数并降低骨髓PCE微核数,与IC组比较有统计学意义(P〈0.05或P〈0.01)。结论:RTP1对辐射所致的小鼠损伤具有一定的保护作用。  相似文献   

4.
A study was made of the radioprotective effect of Adeturon, a protective agent obtained in Bulgaria, on mice with Luis lung tumors exposed to fractionated radiation. The effect of the radioprotector on a radiation-induced injury to normal tissue was estimated by the number of leucocytes in the peripheral blood and its count, cellularity of bone marrow and spleen and the mass of the latter, and by the number of exogenous and endogenous CFUs. A pronounced radioprotective effect of Adeturon was implemented through maintaining or normalizing the indices under study impaired by tumor inoculation or irradiation.  相似文献   

5.
The radioadaptive survival response induced by a conditioning exposure to 0.45 Gy and measured as an increase in 30-day survival after mid-lethal X irradiation was studied in C57BL/6N mice. The acquired radioresistance appeared on day 9 after the conditioning exposure, reached a maximum on days 12-14, and disappeared on day 21. The conditioning exposure 14 days prior to the challenge exposure increased the number of endogenous spleen colonies (CFU-S) on days 12-13 after the exposure to 5 Gy. On day 12 after irradiation, the conditioning exposure also increased the number of endogenous CFU-S to about five times that seen in animals exposed to 4.25-6.75 Gy without preirradiation. The effect of the interval between the preirradiation and the challenge irradiation on the increase in endogenous CFU-S was also examined. A significant increase in endogenous CFU-S was observed when the interval was 14 days, but not 9 days. This result corresponded to the increase in survival observed on day 14 after the challenge irradiation. Radiation-inducted resistance to radiation-induced lethality in mice appears to be closely related to the marked recovery of endogenous CFU-S in the surviving hematopoietic stem cells that acquired radioresistance by preirradiation. Preirradiation enhanced the recovery of the numbers of erythrocytes, leukocytes and thrombocytes very slightly in mice exposed to a sublethal dose of 5 Gy, a dose that does not cause bone marrow death. There appears to be no correlation between the marked increase in endogenous CFU-S and the slight increase or no increase in peripheral blood cells induced by the radioadaptive response. The possible contribution by some factor, such as Il4 or Il11, that has been reported to protect irradiated animals without stimulating hematopoiesis is discussed.  相似文献   

6.
Young adult (6 weeks old) female CBA mice were exposed to whole-body irradiation with either 2.5-Gy fast fission neutrons of 1 MeV mean energy or 6.0-Gy 300 kVp X rays at centerline dose rates of 0.1 and 0.3 Gy/min, respectively. The weight of spleen and animal and the weight, cellularity, and histological structure of the thymus were studied at different times after irradiation. Thymic recovery after whole-body irradiation showed a biphasic pattern with minima at 5 and 21 days after irradiation and peaks of regeneration at Days 14 and 42 after X irradiation or at Days 14 and 70 after neutron irradiation. After the second phase of recovery, a marked decrease in relative thymus weight and cellularity was observed, which lasted up to at least 250 days after irradiation. Splenic recovery showed a monophasic pattern with an overshoot on Day 21 after irradiation. After neutron irradiation a late decrease in relative spleen and animal weight was observed. The observed late effects on thymus and spleen weight and thymus cellularity are discussed in terms of a persistent defect in the bone marrow.  相似文献   

7.
目的:观察减毒沙门氏菌携带的血小板第四因子活性片段PF417 70 的放射保护作用。方法:通过口服途经喂饲小鼠携带PF4活性片段的减毒沙门氏菌,在第 2次喂饲后小鼠接受 70 0cGy全身照射,然后观察PIRES2 EGFP PF417 70 在小鼠体内的表达,并观察小鼠的造血恢复情况。结果:在小鼠的肝脏、脾脏、肾脏、小肠、外周血及骨髓均能检测到GFP的表达和转基因的整合。与对照组比较,实验组小鼠的生存期明显延长,照射后第 7d和 1 4d骨髓有核细胞数、骨髓培养的CFU GM和HPP CFC数量明显增加 (P <0 0 5 )。结论:首次应用减毒沙门氏菌SL32 61为载体来介导PF4活性片段的生物学作用,并证实通过口服途径可以保护小鼠免受放射损伤,并促进放射损伤后小鼠的造血恢复。  相似文献   

8.
Summary In mice, persisting radiation-induced growth retardation of hematopoietic tissue suggested that at least part of the surviving stem cells are genetically injured. Additional mitotic stress some time after the radiation insult might remove injured stem cells, thus improving the overall recovery of the irradiated bone marrow.Mice were treated with 5 Gy whole-body gamma irradiation. Two weeks later half of the animals were injected i.v. with 150 mg/kg 5-fluorouracil (5-FU), the other half remained untreated (5 Gy-controls). 2 or 10 weeks later, femoral cellularity and CFU-S content, proliferation ability of transplanted bone marrow and the compartment ratio (CR; ratio of splenic IUdR incorporation at day 3 and number of CFU-S transfused) were determined.Four weeks after 5 Gy and 2 weeks after 5-FU treatment all parameters showed significant impairment of recovery. 12 weeks after 5 Gy and 10 weeks after 5-FU CFU-S and CR were still reduced compared to the 5 Gy-controls. 5-FU treatment of unirradiated mice did not produce permanent effects on the quality of stem cells or the hematopoietic microenvironment. It is concluded, therefore, that an increased proliferation stimulus does not aid in the removal of injured CFU-S and may even impair recovery of bone marrow functions by increasing the proportion of genetically injured stem cells which continue proliferation.Dedicated to Prof. L.E. Feinendegen on the occasion of his 60th birthday  相似文献   

9.
The paper deals with the recovery process of some parameters in the spleen and bone marrow till day 60 after continuous irradiation with a daily dose of 476.5 mGy (50 R), 957 mGy (100 R) and 4785 mGy (500 R) up to the total accumulated dose of 9570 mGy (1000 R). The recovery process in the spleen and bone marrow are relatively significant and completed till day 28 or 60 respectively after irradiation.  相似文献   

10.
11.
Bone marrow cellularity in the femur, mass and cellularity of the spleen and small intestine, and nucleic acid concentration in the leukocyte mass of blood were investigated after the intraperitoneal administration of betamide (500 mg/kg) 15 min before gamma irradiation of mice with doses of 4, 7 and 9 Gy. The number of myelokaryocytes and splenocytes in the protected animals was shown to exceed considerably that in the controls on days 3 and 9 after irradiation with the three doses. With betamide injected on day 9 following irradiation the number of nucleated cells of the small intestine was larger and the nucleic acid concentration in leukocytes higher than the same indices in the irradiated control.  相似文献   

12.
《Free radical research》2013,47(11):1344-1361
Abstract

Protection of γ-ray-induced injury in hematopoietic and gastrointestinal (GI) systems is the rationale behind developing radioprotectors. The objective of this study, therefore, was to investigate the radioprotective efficacy and mechanisms underlying sesamol in amelioration of γ-ray-induced hematopoietic and GI injury in mice. C57BL/6 male mice were pre-treated with a single dose (100 or 50 mg/kg, 30 min prior) of sesamol through the intraperitoneal route and exposed to LD50/30 (7.5 Gy) and sublethal (5 Gy) dose of γ-radiation. Thirty-day survival against 7.5 Gy was monitored. Sesamol (100 mg/kg) pre-treatment reduced radiation-induced mortality and resulted survival of about 100% against 7.5 Gy of γ-irradiation. Whole-body irradiation drastically depleted hematopoietic progenitor stem cells in bone marrow, B cells, T cell subpopulations, and splenocyte proliferation in the spleen on day 4, which were significantly protected in sesamol pre-treated mice. This was associated with a decrease of radiation-induced micronuclei (MN) and apoptosis in bone marrow and spleen, respectively. Sesamol pre-treatment inhibited lipid peroxidation, translocation of gut bacteria to spleen, liver, and kidney, and enhanced regeneration of crypt cells in the GI system. In addition, sesamol pre-treatment reduced the radiation-induced pattern of expression of p53 and Bax apoptotic proteins in the bone marrow, spleen, and GI. This reduction in apoptotic proteins was associated with the increased anti-apoptotic-Bcl-x and PCNA proteins. Further, assessment of antioxidant capacity using ABTS and DPPH assays revealed that sesamol treatment alleviated total antioxidant capacity in spleen and GI tissue. In conclusion, the results of the present study suggested that sesamol as a single prophylactic dose protects hematopoietic and GI systems against γ-radiation-induced injury in mice.  相似文献   

13.
This paper deals with the evaluation of histological changes in the bone marrow, spleen and thymus of mice after continuous irradiation with a dose rate of 0.957 Gy/day and a total accumulated dose of 19.14 Gy. Erythropoiesis in the spleen could be recovered quickly, significantly exceeding the spleen erythropoiesis of the controls on the seventh post-irradiation day. Myelopoiesis in the bone marrow could be recovered until the 21st day and erythropoiesis until the 28th day after the end of irradiation. Lymphopoiesis in the thymus could be recovered on the 28th day approximately and in the spleen roughly on the 60th day after the end of irradiation.  相似文献   

14.
Carnosine given to adult animals together with potable water one day prior to gamma-irradiation or injected in a single intraperitoneal dose one hour after irradiation enhances colony formation by haemopoietic stem cells migrating from the bone marrow to the spleen. In young animals with a high colony-forming activity carnosine either decreases or does not influence at all the efficiency of colony production.  相似文献   

15.
为探讨载氢-纳米氧化铈微泡对小鼠辐射损伤的防护作用。本研究检测载氢-纳米氧化铈微泡的表征,并将60只BALB/c小鼠随机分为正常对照组、照射对照组、载氢-纳米氧化铈微泡组。小鼠经6Gy x射线一次性全身照射(剂量率2 Gy/min)。于照射后3 d和8 d处死小鼠,检测其外周血细胞数、脾脏和胸腺指数、骨髓和脾脏组织病理学变化。结果显示,照射后3 d和8 d,与正常对照组相比,载氢-纳米氧化铈微泡组和照射对照组的白细胞均明显下降,相比照射对照组,载氢-纳米氧化铈微泡组有改善(p<0.05或p<0.01);而载氢-纳米氧化铈微泡组和照射对照组的红细胞数和血红蛋白均略有下降,但差异无统计学意义。与正常对照组相比,微泡组的胸腺指数、脾脏指数均有下降,和照射对照组相比,载氢-纳米氧化铈微泡组的胸腺指数明显改善(p<0.05或p<0.01)。照射后3 d,与正常对照组相比,照射对照组的骨髓细胞较少,存在细胞碎片,载氢-纳米氧化铈微泡组骨髓细胞数量略有减少,存在细胞核松散现象。而照射后8 d,与正常对照组相比,照射对照组的骨髓细胞几乎找不到,载氢-纳米氧化铈微泡组骨髓细胞有一定数量,存在细胞凋亡现象。本研究表明,载氢-纳米氧化铈微泡通过保护造血组织、改善造血功能,对机体起到一定的辐射防护作用。  相似文献   

16.
The effect of cyclophosphamide on the organ weight, DNA and basic protein content in nuclei of bone marrow, thymus and spleen of rats was studied. Animals were examined 6, 12 and 24 hours and 3, 5, 10, 20 and 30 days after intraperitoneal application of cyclophosphamide in the doses of 100 and 200 mg X kg-1 of body weight. From the 5th day after application a marked decrease in weight and cellularity of all organs was observed. Amounts of DNA and basic proteins in nuclei of bone marrow and spleen were higher as compared with controls and their increase occurred prior to recovery of cellularity and organ weight, that was initiated within 5 and 10 days after cyclophosphamide treatment. Changes in the thymus persisted for a longer period of time and recovery was incomplete even at the day 30 after cyclophosphamide application. In accordance with these data no increase in DNA and basic protein amounts in the thymus nuclei was observed.  相似文献   

17.
Sensitive cocultivation techniques were applied to study the radiation-induced activation of endogenous retroviral genomes in different mouse strains by the alpha-emitting radionuclide 224Radium. Activated infectious C-type retroviruses were detected in spleen, bone marrow and bone tissues of C57BL/6-, BALB/c- and NMRI mice. The titres of high-dose-irradiated animals were higher than those found in low-dose-irradiated animals. Infectious retrovirus could be detected with a dose of 13.2 rad (maximum dose rate 0.9 rad/day) in the skeleton, and a dose of 4.2 rad (maximum dose rate 0.3 rad/day) in the spleen. The virus activation pattern was different in the three mouse strains. These data indicate that activation of endogenous retroviral genomes by alpha-irradiation shows a dose-effect relationship and a dependence on the genetic background of the mouse.  相似文献   

18.
The radioprotective effects of various concentrations (0, 0.25, 0.5, 1, 2, 5, 10, 17.5, 25, 50, 75 and 100 mg/kg b.wt.) of mangiferin (MGN) was studied in the DBAxC57BL mice whole body exposed to 10 Gy of gamma-irradiation. Treatment of mice with different doses of MGN, one hour before irradiation reduced the symptoms of radiation sickness and delayed the onset of mortality when compared with the non-drug treated irradiated controls. The radioprotective action of MGN increased in a dose dependent manner up to 2mg/kg and declined thereafter. The highest radioprotective effect was observed at 2mg/kg MGN, where greatest number of animals survived against the radiation-induced mortality. The administration of 0.5, 1, 2, 5, 10 and 17.5 mg/kg MGN reduced the radiation-induced gastrointestinal death as evident by a greater number of survivors up to 10 days in this group when compared with the DDW + 10 Gy irradiation group. A similar effect of MGN was observed for the radiation-induced bone marrow deaths also. Our study demonstrates that mangiferin, a gluosylxanthone, present in the Mangifera indica protected mice against the radiation-induced sickness and mortality and the optimum protective dose of 2mg/kg was 1/200 of LD50 dose (400 mg/kg) of MGN. The administration of 400 mg/kg MGN induced 50% mortality, therefore LD50 of the drug was considered to be 400 mg/kg.  相似文献   

19.
The present study was designed to measure by quantitative and kinetic methods the production and renewal of natural killer (NK) cells in congenitally B-lymphocyte-deficient (CBA/N) mice. The total NK activity (percent specific lysis corrected for changes in whole organ cellularity) of the bone marrow and spleen of immunologically normal (CBA/CaJ) and CBA/N mice was assayed prior to and immediately after 48 h treatment (2 X/day, i.p.) with the cell cycle poison hydroxyurea (HU) and at various intervals throughout the subsequent post-HU recovery period. The total NK activity (TNKA) of untreated CBA/N bone marrow was 154% of that of CBA/CaJ bone marrow while the TNKA of CBA/N spleen was not significantly different (112%) from that of CBA/CaJ spleen. At the conclusion of 48 h HU, bone marrow TNKA of CBA/N and CBA/CaJ mice fell to 60 and 49%, respectively, of their saline-injected (2 X/day, i.p.) control levels, while spleen TNKA fell to 42 and 61%, respectively, of their saline-injected control levels. In the bone marrow, NK cell depletion in response to HU was more rapid in CBA/N mice (day 0.5 after HU) than in CBA/CaJ mice (day 2 after HU). TNKA of the spleen also decreased more rapidly in CBA/N mice (day 2 after HU) than in CBA/CaJ mice (day 3 after HU). The data indicate an enhanced production and turnover of NK cells in CBA/N mice relative to CBA/CaJ mice. Moreover, increased production and renewal of NK cells in CBA/N mice together with virtually unchanged levels of NK activity (112% of CBA/CaJ mice) in CBA/N mouse spleens indicate that mature lytic NK cells in CBA/N spleen but not bone marrow have a significantly shorter post-mitotic life span than do NK cells in the spleens of immunologically normal (CBA/CaJ) mice.  相似文献   

20.
It was shown that the administration of adrenaline before or after X-irradiation intensified the recovery of mouse haemopoiesis. When adrenaline was administered before irradiation the survival of CFUs (endo- and exo-tests) increased and the bone marrow cellularity and the spleen weight were restored more rapidly than those of the controls. With adrenaline administered after irradiation, the survival of endo-CFUs increased, the bone marrow cellularity was restored and the spleen weight increased.  相似文献   

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