金银花黄酮对小鼠免疫调节作用的研究

目的:探讨金银花黄酮对小鼠血清免疫酶活性与淋巴器官的抗氧化作用。方法:将50只昆明小鼠随机分为5组(n=10):正常组、模型组、低剂量组、中剂量组、高剂量组。模型组和正常组小鼠生理盐水灌胃,低、中、高剂量组分别给予金银花黄酮100 mg/kg、200 mg/kg、400 mg/kg体重灌胃。连续灌胃7周后,除正常组注射生理盐水,其他各组小鼠均采用25 mg/kg体重的地塞米松连续3 d皮下注射,造成免疫抑制后继续灌胃1周,处死全部小鼠,取血和胸腺、脾脏,称重胸腺和脾脏,计算小鼠脏器指数,测定血浆中酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、溶菌酶(LSZ)活力,以及胸腺和脾脏匀浆中单胺氧化酶(MAO)、总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)、丙二醛(MDA)。结果:金银花黄酮能显著提高免疫抑制小鼠的脏器指数,增加免疫抑制小鼠血清ACP、AKP和LSZ活力,提高免疫抑制小鼠的脾脏、胸腺组织T-AOC和SOD活性,而明显降低MAO和MDA含量。结论:金银花黄酮能显著调节小鼠血清免疫酶活性,提高淋巴器官的抗氧化功能,表明具其有良好的免疫调节功能。     

海藻酸钠寡糖对小鼠免疫及 抗氧化功能的影响

目的研究海藻酸钠寡糖对小鼠免疫及抗氧化活性的影响。方法采用不同浓度的海藻酸钠寡糖分别对小鼠连续灌胃15d后,测量小鼠生长性能、小鼠胸腺和脾脏指数以及小鼠血浆中SOD和GSH的活性。结果海藻酸钠寡糖能促进小鼠的生长性能,提高小鼠的胸腺和脾脏指数。其中给小鼠灌注高浓度的海藻酸钠寡糖15d后,与对照组相比,小鼠的特定生长率和增重率分别提高了37.0%和48.5%(P0.01),小鼠胸腺和脾脏指数分别提高了18.8%和21.7%(P0.01)。海藻酸钠寡糖还能增加小鼠的抗氧化活性,与对照组相比,灌注高浓度海藻酸钠寡糖组小鼠的SOD和GSH-Px活性分别提高了92.6%和35.9%(P0.01)。结论海藻酸钠寡糖能促进小鼠的生长性能,增强小鼠的免疫和抗氧化功能。     

松茸多糖抗辐射功能的初步研究

预防给予小鼠松茸多糖(PTM),测定小鼠在受到2 Gy X线照射后,脾和胸腺重量、T淋巴细胞转化能力、外周血中白细胞数和肝组织中SOD、CAT、GSH-Px活性及MDA含量的变化,结果显示PTM处理组小鼠的各项指标与辐射对照组比较均有显著性差别,提示PTM可促进机体自由基的清除,增加机体抗氧化能力,对辐射所致的免疫损伤有明显的保护作用。     

β-蜕皮激素对小鼠胸腺退化的保护作用

目的通过腹腔注射地塞米松(Dex)构造小鼠胸腺退化模型,探究β-蜕皮激素(Ecd)对小鼠胸腺退化的保护作用。方法小鼠随机分为空白对照组、胸腺退化模型组以及3个给药组(Ecd 50 mg/kg、75 mg/kg和100 mg/kg)。腹腔注射给药7 d,于采集胸腺前15 h给予模型组和给药组腹腔注射Dex造模。取小鼠胸腺组织,计算胸腺指数,HE染色切片观察胸腺组织变化,免疫组织化学检测胸腺组织中相关凋亡基因Bcl-2和Bax蛋白的表达。结论 Ecd可提高胸腺指数,保护胸腺组织结构,有效提高Bcl-2的表达并降低Bax的表达,从而提高Bcl-2/Bax比率,抑制胸腺细胞凋亡,提高胸腺细胞存活率。     

海蜇胶原蛋白肽的降血脂及抗氧化作用的研究

本研究以海蜇胶原蛋白为原料,经酶解得到海蜇胶原蛋白肽,探讨海蜇胶原蛋白肽对小鼠血脂的影响及抗氧化作用。以高脂饲料喂养ICR小鼠,建立高脂血症模型,研究胶原蛋白肽对小鼠肝系数和脂肪系数的变化情况及小鼠血脂水平、肝组织抗氧化功能的影响。结果表明海蜇胶原蛋白肽能显著降低小鼠肝系数和脂肪系数,能显著降低高脂血症小鼠血清总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、动脉硬化指数(LDL-C/HDL-C)水平,升高高密度脂蛋白胆固醇(HDL-C)和抗动脉粥样硬化因子(HDL-C/TC);能提高肝组织超氧化物歧化酶(SOD)谷胱甘肽过氧化物酶(GSH-Px)的活力,并能减低丙二醛(MDA)的含量。海蜇胶原蛋白肽具有辅助减低血脂水平和增强抗氧化功能的作用。     

大豆异黄酮对电离辐射小鼠淋巴细胞的防护作用

目的研究大豆异黄酮(SI)对小鼠淋巴细胞的辐射防护作用。方法24只雄性昆明小鼠,随机分为正常对照组、辐射对照组和辐射补充0.5%SI组,喂养2周后,4.0Gy照射。照射后24 h处死小鼠,取血、胸腺和脾脏分离淋巴细胞,进行血淋巴细胞计数、观察DNA损伤情况;培养胸腺和脾脏淋巴细胞,检测3H-dT掺入量,观察淋巴细胞的增殖能力,计算淋巴细胞的增殖指数。结果辐射使小鼠胸腺和脾脏淋巴细胞数明显减少、胸腺淋巴细胞增殖能力和脾脏淋巴细胞转化指数降低、血淋巴细胞DNA损伤增加,这些变化均具有统计学意义;补充SI可降低胸腺和脾脏淋巴细胞数的减少幅度,降低胸腺淋巴细胞增殖能力和脾脏淋巴细胞转化指数下降幅度,减少辐射对血淋巴细胞DNA损伤程度,其中SI对胸腺淋巴细胞增殖能力和对血淋巴细胞DNA损伤程度的防护作用与辐射对照组相比有统计学意义。结论大豆异黄酮可对小鼠的血、胸腺和脾脏淋巴细胞有一定的辐射防护作用。     

枸杞多糖抗氧化作用的研究

目的:研究枸杞粗多糖(Lycium Barbarum Polysaccharide,LBP)在小鼠体内的抗氧化作用。方法:用高(400mg/kg.d)、中(200mg/kg.d)、低(100mg/kg.d)剂量的枸杞粗多糖生理盐水溶液对D-半乳糖(100mg/kg.d)之衰老模型小鼠和正常小鼠灌胃。结果:枸杞粗多糖能较显著(P0.01)提高小鼠血清、肝脏及脑组织中SOD活性,降低MDA含量;极显著(P0.01)提高正常小鼠常压耐缺氧能力和游泳抗疲劳能力;此外小鼠的脾指数和胸腺指数均得到显著提高,表明枸杞粗多糖对提高小鼠的机体免疫水平具有重要的促进作用。结论:枸杞粗多糖对小鼠具有显著的抗氧化、抗衰老作用。     

海参花抗氧化作用研究(英文)

目的:近年来关于天然活性成分的抗氧化特性研究越来越受到人们的关注,大量研究表明海参能通过抗氧化作用,减轻自由基对组织的损伤,提高机体免疫力。环磷酰胺可引起组织氧化损伤,导致卵巢早衰。为此,本文着重研究海参花对卵巢早衰(POF)小鼠的抗氧化作用。方法:选取健康雌性昆明小鼠80只,随机分为8组,每组10只,分别为正常组,模型组,海参花水提物低、高剂量组,海参花醇提物低、高剂量组,海参花冻干粉组和阳性药组。除正常组每天注射生理盐水外,其余各组每天注射环磷酰胺(28mg/kg),连续5天,造成小鼠卵巢早衰、生殖系统紊乱。造模成功后,治疗组分别灌服海参花提取物和阳性药,正常组和模型组给予同体积蒸馏水。末次灌胃禁食,处死迅速解剖取出卵巢和子宫,低温下匀浆组织。测定各组小鼠卵巢及子宫组织中总蛋白含量、超氧化物歧化酶(SOD)活性、谷胱甘肽过氧化物酶(GSH-Px)活性以及丙二醛(MDA)含量,并测定各组小鼠间子宫、卵巢、脾、胸腺脏器系数。结果:与模型组相比,海参花提取物能显著增加小鼠的子宫、卵巢、胸腺等脏器重量,升高卵巢及子宫组织中总蛋白含量、SOD活性、GSH-Px活性,并能降低MDA含量。结论:海参花提取物能改善环磷酰胺引起的卵巢和子宫氧化损伤,具有良好的抗氧化作用,为海参花的研究开发提供理论依据。     

沙棘Vp对辐射损伤小鼠的保护及免疫功能作用研究

本文探讨了沙棘Vp对X射线辐射损伤小鼠的保护作用。将150只昆明种小白鼠分为正常对照组、阳性对照组、辐射对照组、沙棘Vp高、中、低剂量组,雌雄各半,除了正常对照组外,其余各组小鼠接受5Gy的X射线一次性的全身均匀照射。检查各小组小鼠外周血中红细胞数、白细胞数,血小板数,测定超氧化物歧化酶的活力,丙二醛水平,小鼠单核巨噬细胞吞噬功能,小鼠血清溶血素生成能力,计算胸腺和脾脏的脏器指数。结果显示沙棘Vp对辐射后的小鼠血象有明显回升(P0.05),超氧化物歧化酶的活力显著增强(P0.05),丙二醛水平下降(P0.05),胸腺和脾脏的脏器指数升高(P0.05),并且显著提高小鼠血清溶血素生成能力,增强小鼠单核巨噬细胞吞噬功能。本研究说明,沙棘Vp对X射线辐射损伤小鼠具有一定的增强免疫及保护作用。     

大豆异黄酮对电离辐射小鼠T淋巴细胞亚群的影响

目的:研究大豆异黄酮对辐射小鼠T淋巴细胞亚群的影响。方法:32只雄性昆明小鼠,随机分为正常对照组、辐射对照组和辐射补充0.5%大豆异黄酮组,喂养两周后,4.0Gyγ射线照射;于照射后两周杀死小鼠取外周血、胸腺和脾脏,流式细胞仪测定T淋巴细胞亚群。结果:辐射使小鼠外周血CD3、CD4和CD8百分比降低,并且CD8的变化有统计学意义;使胸腺和脾脏的CD3和CD4百分比升高、CD8百分比降低,其中CD4的升高显著(P<0.05)。补充大豆异黄酮,可使外周血、胸腺和脾脏CD3以及血CD4比例升高,但对辐射引起的CD8变化无明显作用。结论:大豆异黄酮可对辐射小鼠的T淋巴细胞亚群起到辐射防护的作用。     

Radiation effects on regeneration and T-cell-inducing function of the thymus

Radiation effects on regeneration and T-cell-inducing function of the thymus were studied in three sets of experiments. When TXB mice were grafted with 1-week-old thymus which had been previously irradiated at various doses, an exponential decrease was observed in the morphological regeneration of the thymus grafts and in their T-cell-inducing function at doses of 600 R and over, showing about 10% that of the control at 1500 R. When in situ thymus of adult mice was locally irradiated, the radiation effect on T-cell-inducing function was less pronounced as compared with the first experiment; i.e., about 40% of the control at 1797 R. When in situ thymus of 1-day-old newborn mice was locally irradiated, regeneration potential of 1-day-old newborn thymus was highly resistant to radiation exposure and no effect on immunologjcal functions was observed even by local irradiation of 2000 R.     

Cellular events during radiation-induced thymic leukemogenesis in mice: abnormal T cell differentiation in the thymus and defect of thymocyte precursors in the bone marrow after split-dose irradiation

Cellular events during the development of thymic lymphomas in young B10.BR mice given leukemogenic split-dose irradiation were studied by examining the differentiation of functional T lymphocyte precursors in the regenerating thymus. It was found that leukemogenic radiation treatment resulted in a sustained depression of the level of thymic cytotoxic T lymphocyte precursors (CTLp) and of mixed lymphocyte reactivity of thymus cells when assessed between 1 and 4 mo after irradiation, in spite of the fact that the total number of thymocytes was restored to the normal level within 2 mo and continued to increase thereafter. In vitro mixing studies of normal thymocytes with thymus cells from split-dose irradiated mice provided no evidence for active suppression as a mechanism for this depressed activity. The ability of bone marrow cells from split-dose irradiated mice to regenerate the thymus and to differentiate into functional CTLp was examined by use of supralethally irradiated Thy-1 congenic recipients. Reconstitution of supralethally irradiated B10.BR Thy-1.2 mice with normal bone marrow from B10.BR Thy-1.1 mice resulted in the complete repopulation of host-thymus with donor-derived cells when assessed at 4 wk after reconstitution. Lymphocytes from the regenerating thymus of these animals were shown to contain high levels of CTLp which were donor-derived. On the other hand, when the recipient mice were reconstituted with bone marrow cells from donor mice which had been split-dose irradiated 1 mo earlier, regeneration of the recipient thymus was severely depressed when assessed at 4 wk to 3 mo after reconstitution. Although variable but small numbers of donor-derived Thy-1+ cells were detected, CTL activity for alloantigen could not be induced in these donor-derived cells. The results suggest that T cell precursors derived from split-dose irradiated donor mice were unable to undergo active proliferation and differentiation into functional CTLp. The significance of these findings on radiation-induced thymic leukemogenesis is discussed.     

Dysfunction of irradiated thymus for the development of helper T cells

The development of cytotoxic T cells and helper T cells in an intact or irradiated thymus was investigated. C57BL/6 (H-2b, Thy-1.2) mice were whole body-irradiated, or were irradiated with shielding over either the thymus or right leg and tail, and were transferred with 1.5 X 10(7) bone marrow cells from B10.Thy-1.1 mice (H-2b, Thy-1.1). At various days after reconstitution, thymus cells from the recipient mice were harvested and a peanut agglutinin low-binding population was isolated. This population was further treated with anti-Thy-1.2 plus complement to remove host-derived cells and was assayed for the frequency of cytotoxic T cell precursors (CTLp) and for the activity of helper T cells (Th). In the thymus of thymus-shielded and irradiated mice, Th activity reached normal control level by day 25, whereas CTLp frequency remained at a very low level during these days. In the thymus of whole body-irradiated mice, generation of CTLp was highly accelerated while that of Th was retarded, the period required for reconstitution being 25 days and more than 42 days for CTLp and Th, respectively. Preferential development of CTLp was also seen in right leg- and tail-shielded (L-T-shielded) and irradiated recipients. Histological observation indicated that Ia+ nonlymphoid cells were well preserved in the thymus of thymus-shielded and irradiated recipients, whereas in L-T-shielded and irradiated recipients, such cells in the medulla were markedly reduced in number. These results suggest strongly that the generation of Th but not CTLp is dependent on radiosensitive thymic component(s), and that such components may represent Ia+ cells themselves in the medulla or some microenvironment related to Ia+ cells.     

Influence of MHC on thymus repopulation following intrathymic transfer of mouse T-cell precursors

T-cell precursors (pre-T cells) traditionally have been detected by their ability to repopulate the thymus of heavily irradiated mice following intravenous injection. Recently, an assay system involving the direct injection of pre-T cells into the thymus of sublethally irradiated animals has been described. Here we report the results of experiments designed to evaluate the ability of bone marrow cells to produce thymic repopulation following intrathymic injection in a wide range of donor-host strain combinations. Irradiated (600 R) mice were injected intrathymically with 2 X 10(6) bone marrow cells which differed from the recipient with respect to their Thy-1 allotype and the percentage of thymus cells expressing either donor- or recipient-type Thy-1 was determined 9 to 23 days after injection. The results of these experiments showed that thymocytes expressing the Thy-1 allotype derived from the donor marrow were only detected when the donor and host were matched at MHC. By contrast, thymic repopulation by MHC-mismatched donor marrow cells could readily be observed when these cells were given intravenously.     

In vivo anti‐inflammatory efficacy of the combined Bowman‐Birk trypsin inhibitor and genistein isoflavone,two biological compounds from soybean

Soybean Bowman‐Birk protease inhibitor (BBI) and genistein, two biological compounds from soybean, are well‐known for their anti‐inflammatory, antioxidant, and anticancer activities. The aim of this study was designing a BBI‐genistein conjugate and then investigating its protective effect on lipopolysaccharide (LPS)‐induced inflammation in BALB/c mice, compared with the effects of combination of BBI and genistein. BBI was purified from soybean and the BBI‐genistein conjugate was synthesized. The BALB/c mice were intraperitoneally treated 2 hours before LPS induction. Our results showed that treatment with the combination of BBI and genistein greatly led to more reduced serum levels of tumor necrosis factor (TNF)‐α and interferon (IFN)‐γ compared with the treatments of BBI alone, the BBI‐genistein conjugate, and genistein alone, respectively. Moreover, the expression of TNF‐α and IFN‐γ in the splenocytes was significantly downregulated along with improving host survival against the LPS‐induced lethal endotoxemia in the same way. Our data support a new combined therapy using BBI and genistein, as natural anti‐inflammatory agents, to develop a new drug for inflammatory diseases.     

The differentiation of bone marrow cells to functional T lymphocytes following implantation of thymus grafts and thymic stroma in nude and AT×BM mice

Cardiac allografts were used to compare the immunologic capacity of nude mice and adult, thymectomized, lethally irradiated, bone marrow-reconstituted (AT × BM) mice. Neither nude nor AT × BM mice were able to reject cardiac allografts of any party. However, both rejected grafts of any party following implantation of neonatal thymus or thymus from 3-week-old syngeneic mice. Irradiated syngeneic thymus grafts (800 R) were equally effective in restoring host responsiveness against allografts. In contrast, allogeneic thymus grafts restored the capacity to reject second-party heart grafts only in AT × BM mice. Second-party grafts persisted indefinitely when placed on nude mice implanted with an allogeneic, unirradiated thymus graft. Third-party grafts transplanted 17 weeks after reconstitution, however, were rejected. Irradiated nude mice given normal littermate bone marrow and simultaneously grafted with second-party thymus and heart allografts also failed to reject their second-party heart grafts. The difference in ultimate capacity to respond between AT × BM and nude mice suggests that a maturational defect exists in the nude mouse enviroment which impedes development of precursor T lymphocytes.     

Studies of the immunological capacity of germ-free mouse radiation chimeras. IV. Cell-mediated immunity

The cell-mediated immune (CMI) response of germ-free mouse radiation chimeras was compared with that of conventional mice. Spleen or thymus cells from chimeric or normal mice were injected intravenously into lethally irradiated, allogeneic hosts. Spleens of the irradiated hosts were assayed for effector cells using the ⁵¹Cr release assay. Spleen cells from syngeneic and allogeneic chimeras and normal mice were equally active in giving rise to effector cells. However, thymus cells from allogeneic chimeras were completely inactive within 9 months post-bone marrow transplant while thymus cells from syngeneic chimeras and normal mice still remained functional. Although allogeneic chimeras contain cells potentially reactive toward host antigens, cells cytotoxic to host antigens were not detectable. In addition, these studies indicate the helper cell and effector cell, both associated with T-derived lymphocytes, represent two different populations.     

Radioprotective and antistressful properties of nitric oxide production modulators

The radioprotective and antistressful activities of L-arginine and the "Pronumol" preparation, in which L-arginine is contained in the complex of proteins with nucleic acids, were studied. In mice repeated peroral intake of L-arginine and "Pronumol" partially prevented radiation-induced and stress-induced lipid peroxidation and DNA degradation in thymus, increased hemopoietic stem cell survival, and prevented an increase in chromosome aberration frequency in bone marrow cells of irradiated mice. When repeatedly administered per os before irradiation, "Pronumol" increased survival of intestinal stem cells in irradiated mice and prevented thymus cell devastation induced by radiation and stress.     

Effects of genistein on early-stage cutaneous wound healing

Wound healing occurs in three sequential phases: hemostasis and inflammation, proliferation, and remodeling. Inflammation, the earliest phase, is considered a critical period for wound healing because immune cells remove damaged tissues, foreign debris, and remaining dead tissue. Wound healing would be delayed without inflammation, and this phase is affected by antioxidation capacity. Therefore, we hypothesized that genistein, which has an antioxidant effect, might modulate the wound healing process by altering the inflammatory response. After three days of acclimation, mice were divided into three groups: control, 0.025% genistein, and 0.1% genistein. After two weeks of an experimental diet, skin wounds were induced. Wounded skin areas were imaged, and the healing rate calculated. To measure lipid peroxidation, antioxidant enzyme expression and activity, and pro-inflammatory cytokine expression, skin and liver tissues were harvested at 12, 24, 48, and 72 h. Genistein did not affect body weight. The rate of wound closure in mice fed genistein was significantly faster than in the control group during the early stage of wound healing, especially in first three days. Cu, Zn-SOD and Mn-SOD expression in wound skin tissue in the 0.1% genistein group was lower than in the control group. However, CAT expression did not differ among groups. We also found that genistein modulated NF-κB and TNF-α expression during the early stage of wound healing. The genistein group had significantly lower hepatic lipid peroxidation and higher SOD, CAT, and GPx activities than the control group. These results suggest that genistein supplementation reduces oxidative stress by increasing antioxidant capacity and modulating proinflammatory cytokine expression during the early stage of wound healing.     

Cell transfer studies in cyclophosphamide-induced tolerance

Thymectomized, irradiated adult CBA mice were restored with various combinations of bone marrow and thymus cells from nontolerant animals and from animals made tolerant to sheep erythrocytes or to hemocyanin with the drug cyclophosphamide. Mice reconstituted with tolerant marrow and thymus responded as well as those that received nontolerant cells. Thus it is concluded that the tolerant state of the transferred marrow and thymus cells is not a significant factor in the tolerant state of the recipient, and that antigenic diversity is restored in the interaction and proliferation of bone marrow and thymus cells that follow transfer.Thymectomized irradiated mice restored with thymocytes, in contrast to unoperated animals, require multiple antigen injections to demonstrate comparable immune response, but develop tolerance normally when treated with cyclophosphamide and antigen. Reconstitution with tolerant marrow and thymus cells resembles the recovery of immune responsiveness seen after lethal irradiation of tolerant mice; in both instances a complete breakdown of immunological tolerance is observed.