Effects of brazilin on induction of immunological tolerance by sheep red blood cells in C57BL/6 female mice

Brazilin was examined for its effects on the induction of immunological tolerance. Brazilin was administered to C57BL/6 female mice for 2 consecutive days before the immunization with high dose SRBC (10⁹ cells) which can produce immunological tolerance. Delayed type hypersensitivity, IgM plaque forming cells, ConA induced IL-2 production and mitogen- or antigen-induced proliferation of lymphocytes were measured as evaluation parameters. Administration of brazilin prior to immunization could keep the DTH and IL-2 production almost optimaly immunized levels. Brazilin also inhibited the elevation of non-specific suppressor cell activity. ConA induced proliferation of splenocytes in high dose SRBC immunized mice was significantly decreased by pretreatment of brazilin. And this might be one of the reason for augmentation of DTH by brazilin. However, IgM plaque forming cells were not affected by the treatment of brazilin. These results indicate that brazilin prevents the induction of immunological tolerance caused by high dose SRBC by suppressing the elevation of suppressor cell activity and by inhibiting the decrease in IL-2 production in C57BL/6 female mice.     

Effects of Brx-019 (acetic acid 3,6a,9-triacetoxy-6,6a,7, 11b-tetrahydro-indeno [2,1-c] chromen-10-yl ester), a Brazilin derivative, on T cell-mediated immune responses in multiple low dose streptozotocin-induced diabetic C57BL/6 male mice

Brx-019 (acetic acid 3,6a,9-triacetoxy-6, 6a,7,11b-tetrahydro-indeno [2,1-c] chromen-10-yl ester) was derived from brazilin (CAS 474-07-7) during a trial designed to search for immunomodulators with lower toxicity and more effective immunomodulating activities than brazilin. Brx-019 was selected as a potential immunomodulator based on its effects on Concanavalin A (Con A)-induced proliferation of splenocytes and the 3-[14,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. Intraperitoneally administered Brx-019 significantly improved delayed type hypersensitivity and increased immunoglobulin M (IgM) plaque forming cells (PFCs) in multiple low dose streptozotocin-induced diabetic mice (MLDS-diabetic mice). This finding suggests that Brx-019 may increase suppressed humoral and cell-mediated immunity in type 1 diabetes. Brx-019 also significantly increased Con A- or alloantigen-induced proliferation of splenocytes, Con A-induced interleukin 2 (IL-2) production from splenocytes, and IL-2-induced proliferation of Con A-activated splenocytes in MLDS-diabetic mice. These results suggest that Brx-019 might improve immunity in diabetic mice by increasing IL-2 production in splenocytes and responsiveness of splenocytes to IL-2, which were suppressed in MLDS-diabetes.     

Effects of brazilin on glucose metabolism in isolated soleus muscles from streptozotocin induced diabetic rats

The present study was performed to evaluate the hypoglycemic mechanism of brazilin. Brazilin significantly reduced plasma glucose level in streptozotocin induced diabetic rats and this effect seems to be mediated by extrapancreatic effects rather than by pacreatic effect because no significant changes were observed in plasma insulin levels. The rates of glycogen synthesis, glycolysis and glucose oxidation in soleus muscle were markedly increased following brazilin treatment to diabetic animals. Glucose transport seemed to be increased by the treatment of brazilin. Brazilin did not affect insulin binding to muscles from streptozotocin induced diabetic rats. These results suggest that potentiation of peripheral glucose utilization may be one of the major causes of hypoglycemic action of brazilin.     

Mechanism of action of Brazilin on gluconeogenesis in isolated rat hepatocytes

The present study was undertaken to investigate the mechanism of action of brazilin on gluconeogenesis and ketogenesis in isolated rat hepatocytes and to elucidate the hypoglycemic mechanism of brazilin. Brazilin decreased gluconeogenesis at 100 micro M in hepatocytes isolated from diabetic rats. Brazilin also decreased basal and glucagon-induced gluconeogenesis in hepatocytes from normal rats. Fatty acids (octanoate or oleate)-induced gluconeogenesis was significantly reduced by brazilin, but ketogenesis was not influenced. The depletion of extracellular or intracellular calcium decreased gluconeogenesis in calcium-depleted media. Brazilin lowered dibutyryl cAMP (Bt2cAMP)-induced gluconeogenesis and the intracellular adenosine 3',5'-cyclic monophosphate (cAMP) level in glucagon-treated hepatocytes. It was also found that brazilin does not require calcium for inhibition of gluconeogenesis, but may inhibit the down-stream of cAMP signaling pathways. These data suggest that a decreased gluconeogenic flux in hepatocytes might at least partly contribute to the hypoglycemic effects of brazilin.     

芍芪多苷对迟发型变态反应小鼠细胞免疫功能的影响

目的探讨在不同免疫状态下,芍芪多苷(Shaoqid-uogan,SQDG)对迟发型变态反应(DTH)小鼠细胞免疫功能的作用。方法采用2,4-二硝基氯苯(DNCB)诱导小鼠DTH模型及环磷酰胺(Cy)诱导小鼠免疫低下或亢进模型。SQDG予小鼠连续灌胃7d。MTT法检测ConA诱导的小鼠胸腺T淋巴细胞增殖,小鼠胸腺细胞增殖法检测ConA诱导的小鼠胸腺T淋巴细胞培养上清中白细胞介素2(IL-2)的活性。结果在小鼠DTH模型,SQDG(120mg·kg-1)可降低耳肿胀、胸腺指数、ConA诱导的胸腺T淋巴细胞增殖反应以及ConA诱导的胸腺T淋巴细胞培养上清中IL-2的活性。DNCB初次致敏当日腹腔注射(ip)Cy(150mg·kg-1)可以造成DTH低下模型,致敏前3 d ip Cy(250mg·kg-1)可造成DTH亢进模型;SQDG(60和120mg·kg-1)能明显上调DTH低下模型小鼠耳肿胀、ConA诱导的小鼠胸腺T淋巴细胞增殖及小鼠胸腺T淋巴细胞培养上清中IL-2的水平;且能明显下调DTH亢进模型小鼠上述指标的水平。结论SQDG对小鼠细胞免疫具有双向调节的作用。     

Ursolic acid enhances the cellular immune system and pancreatic β-cell function in streptozotocin-induced diabetic mice fed a high-fat diet

This study investigated the effects of ursolic acid on immunoregulation and pancreatic β-cell function in type 1 diabetes fed a high-fat diet for 4 weeks. Male mice were divided into non-diabetic, diabetic control, and diabetic-ursolic acid (0.05%, w/w) groups, which were fed a high-fat (37% calories from fat). Diabetes was induced by injection of streptozotocin (200 mg/kg B.W., i.p.). Ursolic acid significantly improved blood glucose levels, glucose intolerance, and insulin sensitivity compared to the diabetic group. The plasma insulin and C-peptide concentrations were significantly higher in the diabetic-ursolic acid group than in the diabetic group. Ursolic acid significantly elevated the insulin levels with preservation of insulin staining of β-cells in the pancreas. In splenocytes, concanavalin (Con) A-induced T-cell proliferation was significantly higher in the diabetic-ursolic acid group compared to the diabetic group, but liposaccharide (LPS)-induced B-cell proliferation did not differ between groups. Ursolic acid enhanced IL-2 and IFN-γ production in response to Con A stimulation, whereas it inhibited TNF-α production in response to LPS stimulation. In this study, neither streptozotocin nor ursolic acid had effects on lymphocyte subsets. These results indicate that ursolic acid exhibits potential anti-diabetic and immunomodulatory properties by increasing insulin levels with preservation of pancreatic β-cells and modulating blood glucose levels, T-cell proliferation and cytokines production by lymphocytes in type 1 diabetic mice fed a high-fat diet.     

Upregulation of heme oxygenase-1 by brazilin via the phosphatidylinositol 3-kinase/Akt and ERK pathways and its protective effect against oxidative injury

Heme oxygenase (HO)-1 is a cytoprotective enzyme that is activated by various phytochemicals. We examined the ability of brazilin to upregulate HO-1 expression in auditory cells. We found that brazilin induced the expressions of HO-1 mRNA and protein in concentration- and time-dependent manners. Brazilin induced nuclear factor-E2-related factor 2 (Nrf2) nuclear translocation, and dominant-negative Nrf2 attenuated brazilin-induced expression of HO-1. Brazilin induced a temporary increase in the phosphorylation of Akt. While LY294002, a non-selective phosphotidylinositol 3-kinase (PI3K) inhibitor, was able to reduce brazilin-induced phosphorylation of Akt and the subsequent induction of HO-1. Brazilin activated the extracellular signal-regulated kinase (ERK) and p38 pathways, and the ERK pathway played an important role in HO-1 expression. Brazilin protected the cells against t-butyl hydroperoxide (t-BHP)-induced cell death. The protective effect of brazilin was abrogated by anti-sense oligodeoxynucleotides (ODN) against the HO-1 gene. These results demonstrate that the expression of HO-1 by brazilin is mediated via the PI3K/Akt and ERK pathways, and this expression inhibits t-BHP-induced cell death in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells.     

Immunoregulatory abnormalities of T cells and hyperreactivity of B cells in the<Emphasis Type="Italic">In Vitro</Emphasis> immune response in pristane-induced lupus mice

Systemic lupus erythematosus (SLE) is characterized by overactive B cells that differentiate into autoantibody-forming cells, aberrant T cell function that provides helping B cells produce autoantibodies, and overproduction of proinflammatory cytokines. However, immunodysregulation in lupus pathogenensis remains incomplete. We examined mitogen-stimulated production of proinflammatory cytokines, cell proliferation, T cell activation, and T cell apoptosis in vitro in pristane-induced lupus BALB/c mice compared to normal mice. LPS-stimulated production of IL-6 and IL-10 by splenocytes and macrophages from pristane-induced lupus mice were remarkably up-regulated compared to normal mice, whereas production of macrophage TNF-alpha was significantly down-regulated. Moreover, in vitro production of IL-2, IL-6, IL-10 and IFN-gamma by Con A-stimulated splenocytes, cell proliferation in LPS- or Con A-stimulated- thymocytes and splenocytes, and expression of CD69+CD4+ T cells in Con A-stimulated splenocytes were greatly increased in cells derived from pristane-induced lupus mice compared to normal mice. In addition, splenic T cells and CD4+ T cells in thymocytes from pristane-induced lupus mice were more resistant than nonautoimmune normal cells to Con A-induced apoptosis. Our findings indicate that immunoregulatory abnormalities of T cells and hyperreactivity of B cells in the in vitro immune responses in pristane-induced lupus mice may explain some of lupus pathogenesis.     

牛膝多糖对T淋巴细胞和天然杀伤细胞功能的影响

牛膝多糖（ＡＢＰ）是从中药牛膝根中分离得到的一种有效成分。ＡＢＰ５０－８００ｍｇ·Ｌ－１在体外增强天然杀伤（ＮＫ）细胞活性和促进伴刀豆球蛋白Ａ（ＣｏｎＡ）诱导的肿瘤坏死因子－β（ＴＮＦ－β）产生；但不能提高ＣｏｎＡ诱导的Ｔ淋已细胞增殖反应和白介素２的产生．ＡＢＰ５０及１００ｍｇ·ｋｇ－１ｉｐ明显提高正常小鼠ＮＫ细胞活性和ＴＮＦ─β生成，增强二硝基氟苯诱导的迟发型超敏反应和对抗环磷酰胺对ＮＫ活性的抑制作用。但对ＣｏｎＡ诱导的Ｔ淋巴细胞增殖反应和白介素２的产生无明显影响。表明ＡＢＰ对Ｔ淋巴细胞功能的影响是有选择性的．ＡＢＰ对ＮＫ细胞的杀伤活性的增强作用是明显的．     

A newly devised formulation for self-medication enhances interferon-gamma production and proliferation of splenic lymphocytes

A newly devised formulation for self-medication in Toyama, PanaWang, is a new herbal medicine (so called Toyama original brand formulation) developed based on traditional philosophy and scientific evidence. We here tried to examine the effect of oral administration of PanaWang on the balance of type I helper T cells (Th1) and Th2 cells. Splenic lymphocytes from normal mice were stimulated with Concanavalin A (Con A) in vitro and the secretion of Th1- and Th2-type cytokines, interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) respectively, was investigated. Con A-induced production of IFN-gamma from spleen cells, but not IL-4, was enhanced by the administration of PanaWang. Increased production of IFN-gamma was also detected in splenic lymphocytes from Th2-predominant BALB/c mice after DNP-immunization, without a change in antigen-specific IgE levels in vivo. Antigen-specific proliferative responses were also increased in lymphocytes from PanaWang-treated mice. These findings raise the possibility that PanaWang has Th1-stimulating activity and induces Th1-predominant immunity.     

Carbofuran suppresses T-cell-mediated immune responses by the suppression of T-cell responsiveness, the differential inhibition of cytokine production, and NO production in macrophages

The effects of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzo-furanol N-methylcarbamate) on the functions of T cells in splenocytes and peritoneal macrophages were examined in view of T-cell-mediated immune response (CMIR) in male C57BL/6 mice. Intraperitoneal administration of carbofuran (0.075, 0.15 and 0.3 mg/kg body weight) resulted in significant suppression of delayed type hypersensitivity (DTH), indicating that it caused the suppression of CMIR. Carbofuran decreased Concanavalin A (Con A)- and alloantigen-induced proliferation, and interleukin (IL)-2 production of splenocytes. In vitro addition of rIL-2 could not completely restore the suppressed T-cell proliferation, and IL-2-induced proliferation of Con A-activated splenocytes was also suppressed, which implied that carbofuran caused defects in IL-2 production and responsiveness of splenocytes to IL-2, leading to the suppression of T-cell proliferation. Con A-induced production of interferon-gamma (IFN-gamma) was significantly suppressed by carbofuran, while that of IL-4 was not affected. The production of transforming growth factor-beta from splenocytes was also significantly inhibited by carbofuran. Judging from these results, carbofuran might directly suppress the cytokine production in T helper 1 (Th1) cells. In addition, IFN-gamma-induced production of nitric oxide (NO) in macrophages was also inhibited by carbofuran, which might be one of the important mechanisms of carbofuran-induced CMIR suppression in mice. Collectively, the present study suggests that carbofuran might suppress CMIR through the suppression of T-cell responsiveness, IFN-gamma production in Th1 cells, and NO generation in macrophages.     

Decreased T-cell mediated hepatic injury in concanavalin A-treated PLRP2-deficient mice

Concanavalin A (Con A) activates innate immunity and causes liver damage mediated by cytotoxic T lymphocytes (CTL) in mice. The Pancreatic lipase-related protein 2 (PLRP2) is induced by interleukin (IL)-4 in vitro in CTLs and associated with CTL functions. We examined the role of PLRP2 in a mouse model of Con A-induced T cell-mediated hepatitis. PLRP2-knockout and wild-type (WT) mice were inoculated with 20 mg/kg Con A. Mice lacking PLRP2 reduced Con A-induced hepatitis, which was manifested by a decrease in serum aminotransferase and histopathological assessment. The expression and secretion of cytokines including tumor necrosis factor-alpha (TNF-α), interferon (IFN)-γ, IL-6, and IL-1β were suppressed in Con A-treated PLRP2-knockout mice. In PLRP2 knockout mice, Con A-induced liver chemokines and adhesion molecules (such as MIP-1α, MIP-1β, ICAM-1 and MCP-1) were also down regulated. In the WT liver treated with Con A, the number of T cells (CD4⁺ and CD8⁺) and macrophages (CD11b⁺ F4/80⁺) increased significantly, while the lack of PLRP2 reduced the number of T cells in the liver, but had no effect on macrophages. The shift of the metabolic profiles was impaired in Con A-treated PLRP2-knockout mice compared to WT mice. In conclusion, these results indicate that PLRP2 deficiency reduces T-cell mediated Con A-induced hepatitis, and suggest PLRP2 is a potential target of anti-inflammatory and immunomodulatory drugs to treat immune-mediated hepatitis.     

Effects of brazilin on GLUT4 recruitment in isolated rat epididymal adipocytes

The effects of brazilin on glucose transport into isolated rat epididymal adipocytes were investigated. Brazilin increased [3H]2-deoxy-D-glucose uptake, which was characterized by an increase in Vmax with no effect on the Km value. Phenylarsine oxide, which inhibits the translocation of glucose transporters, decreased brazilin-stimulated glucose transport to the basal level. The inhibition of phosphatidylinositol 3-kinase (PI3-kinase) with wortmannin also blocked brazilin-stimulated glucose transport. Western blot analysis with an anti-GLUT4 antibody revealed that brazilin increased the translocation of GLUT4 from intracellular pools to the plasma membrane. Brazilin, in combination with phorbol ester, showed an additive effect on glucose transport. The stimulating effect of phorbol ester on glucose transport was inhibited by staurosporine, but the effect of brazilin remained unchanged. Protein kinase C activity was not influenced by brazilin treatment. The inhibition of protein synthesis showed no effect on brazilin-stimulated glucose transport, and GLUT4 content in the total membrane fraction was not altered as a result of treatment with brazilin for 4 hr. Metabolic labeling of GLUT4 with [35S]methionine showed that de novo synthesis of GLUT4 was not induced by brazilin. These data suggest that brazilin may increase glucose transport by recruitment of GLUT4 from intracellular pools to the plasma membrane of adipocytes via the activation of PI3-kinase. However, the effect of brazilin may not be mediated by GLUT4 synthesis and protein kinase C activation.     

Demethyleneberberine attenuates concanavalin A-induced autoimmune hepatitis in mice through inhibition of NF-κB and MAPK signaling

Demethyleneberberine (DMB) is a natural product which has been reported to possess mitochondria-targeting anti-oxidative and anti-inflammatory effect. However, the pharmacological action and molecular mechanism of DMB on autoimmune hepatitis (AIH) have not been explored. In this study, AIH was induced by intravenously injecting Con A (20 mg/kg) in mice for 8 h, and DMB protected against Con A-induced AIH, evidenced by obvious reduction of hepatic enzymes in serum and histological lesion. DMB significantly inhibited the infiltration of CD4⁺ T cell and Kupffer cell as well as the expression of inflammatory cytokines, such as TNF-α, IL-6, IL-1β and IFN-γ by ELISA and qPCR analysis. Western blotting analysis illustrated that DMB remarkably inhibited Con A-induced phosphorylation of IKK, IκB, NF-κB p65, ERK, JNK, p38 MAPK and STAT3 induced by Con A. Moreover, DMB also effectively suppressed hepatic oxidative stress with reduction of MDA and elevation of GSH. Taken together, our findings indicated that DMB could prevent Con A-induced AIH by regulating NF-κB and MAPK signaling, suggesting that DMB can serve as a promising candidate for therapy of AIH.     

Inhibition of phosphodiesterase 7A ameliorates Concanavalin A-induced hepatitis in mice

An intravenous injection of Concanavalin A (Con A) elevated the serum level of alanine aminotransferase (ALT) activity, a marker for liver damage, and an oral administration of PDE7A inhibitor SUN11817 suppressed the increase of ALT activity in a dose-dependent manner. Histological analysis revealed that Con A injection caused extensive liver damage, and that the SUN11817 treatment improved the degenerative change in the liver. In addition, SUN11817 inhibited not only the production of IL-4 and TNF-α in the Con A-induced hepatitis model but also that in vitro by murine splenocytes stimulated with α-galactosylceramide, an activator specific for NKT cells. The Con A injection to mice also induced expression of Fas ligand (FasL) on NKT cells, which was significantly prevented by SUN11817. As NKT cells are known to contribute to the pathogenesis in Con A-induced hepatitis by producing cytokines such as IL-4 and TNF-α and inducing FasL-mediated hepatocyte injury, it is thought that PDE7A inhibitor SUN11817 improves liver injury in the Con A model by blocking cytokine production and FasL expression in NKT cells. PDE7A might be a novel pharmaceutical target for hepatitis.     

吗啡依赖小鼠免疫功能的变化

以饮用吗啡药水法建立小鼠依赖模型,探讨其免疫机能的改变。发现,与对照组比较,依赖小鼠腹腔巨噬细胞(PMΦ)吞噬中性红能力下降,LPS 10μg·ml~(-1)诱生的IL-1及TNF活性降低。吗啡亦抑制Con A/LPS刺激的胸腺细胞和脾细胞参入[~3H]TdR,使DNFB所致迟发型过敏反应下降。若脾细胞单独或与Con A 3μg·ml~(-1)共同培养24h,成瘾小鼠产生IL-2的能力皆明显弱于对照。但Con A活化3d的脾母细胞对重组IL-2的反应性以及产生抗SRBC的空斑形成细胞数和抗体的水平,在二组之间均未见差异。     

In vitro ozone exposure inhibits mitogen-induced lymphocyte proliferation and IL-2 production

Human blood mononuclear cells were exposed to ozone in vitro and thereafter analyzed for competence in mitogen-induced proliferation as well as IL-1 and IL-2 production. Proliferative responses induced by phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM) were all depressed in lymphocytes exposed to an ozone concentration of 1 ppm for 4-6 h. The response to PWM was most sensitive to the ozone effect (38% suppression); responses to Con A and PHA were suppressed to a lesser extent, 23% and 18%, respectively, and were not significantly different from each other. PWM responses were affected at an ozone concentration as low as 0.1 ppm; however, no suppression of Con A-induced proliferation was seen below 0.18 ppm or of PHA-induced proliferation below 0.5 ppm. When lymphocytes and monocytes were exposed separately to ozone and then mixed back with control air-exposed monocytes or lymphocytes, both cell types appeared to be affected and the functional defects caused by the pollutant were additive. Monocyte IL-1 production induced by endotoxin was not affected by ozone exposure, while surface expression of HLA-DR on exposed monocytes was reduced by 40% 24 h after exposure. Moreover, lymphocytes exposed to ozone produced 46% less IL-2 while expressing similar surface density of IL-2 receptors. Taken together, these results show that exposure to ozone has distinct adverse effects on lymphocytes and monocytes, both of which are important in local immune defenses in the lung.     

Brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing the NF-κB pathway in human dermal fibroblasts

Brazilin (7, 11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol), the major component of Caesalpinia sappan L., is a natural red pigment used for histological staining. Recent studies have shown that brazilin exhibits distinct biological effects, including anti-hepatotoxicity, antiplatelet activity, and anti-inflammatory activities. In the present study, we evaluated the effects of brazilin on MMP-1 and -3 expressions in human dermal fibroblasts exposed to ultraviolet B (UVB) irradiation. Brazilin showed protective effect on UVB-induced loss of cell viability of fibroblasts. Brazilin also blocked significantly UVB-induced Reactive Oxygen Species generation in fibroblasts. Brazilin inhibited UVB-induced MMP-1/3 expressions and secretions in a dose-dependent manner. Moreover, UVB-induced NF-κB activation was completely blocked by treatment with brazilin. These findings suggest that brazilin inhibits UVB-induced MMP-1/3 expressions and secretions by suppressing of NF-κB activation in human dermal fibroblasts. Thus, brazilin might be used as a potential agent for treatment of UV-induced skin photoaging.     

Alpha-lipoic acid protects mice against concanavalin A-induced hepatitis by modulating cytokine secretion and reducing reactive oxygen species generation

BackgroundAlpha-lipoic acid (α-LA), which exits in almost all types of prokaryotic and eukaryotic cells, is a key regulator of energy metabolism in mitochondria. This study was designed to explore the protective effect of α-LA against concanavalin A (Con A)-induced hepatitis in mice and explore the potential mechanism.MethodsAcute autoimmune hepatitis was induced by intravenous (IV) injection of Con A (15 mg/kg) in C57BL/6 mice. α-LA (100 mg/kg) was administered four days before Con A injection. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and histopathological change of the liver tissue were measured. Serum cytokine TNF-α, IL-6, IFN-γ and IL-10 were detected by ELISA. The mRNA levels of these inflammatory cytokines in the liver were detected by RT-PCR. Malondialdehyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD) and reduced/oxidized glutathione (GSH/GSSG) in liver were determined using commercial kits. Phosphorylated NF-κB p65, IκBα and phosphorylated MAPK were measured by Western blot.ResultsCon A injection induced severe immune responses and extensive hepatocellular apoptosis within 12 h. Pretreatment of α-LA markedly reduced the serum ALT and AST activity and the increase of plasma TNF-α, IL-6, IFN-γ and IL-10. In addition, α-LA pretreatment decreased the tissue MPO activity and lipid peroxidation, but increased SOD and GSH levels. α-LA inhibited the phosphorylation of NF-κB p65, IκBα and JNK.ConclusionPretreatment of α-LA markedly attenuated Con A-induced hepatitis by modulating cytokine secretion and reducing reactive oxygen species generation.     

木瓜苷对环磷酰胺增强的小鼠接触性超敏反应的影响(英文)

目的　探讨胸腺在环磷酰胺 (Cy)增强的小鼠接触性超敏反应 (CHS)中的作用及木瓜苷 (GCS)对胸腺T淋巴细胞亚型的影响。方法　采用了 2 ,4 二硝基氟苯 (DNFB)诱导小鼠CHS模型及Cy诱导小鼠增强CHS模型 ,检测ConA诱导的小鼠脾脏T淋巴细胞增殖、胸腺T淋巴细胞亚型和ConA诱导的胸腺T淋巴细胞培养上清中TGF β1,IL 4和IL 2水平。结果　小鼠CHS模型中 ,ConA诱导的脾淋巴细胞增殖增强 ,CD4 +CD8+双阳性胸腺T淋巴细胞比例增加 ,胸腺细胞产生的Th1和Th3型细胞因子IL 2和TGF β1水平增高而Th2型细胞因子IL 4水平降低。DNFB初次致敏前 3d腹腔注射Cy (2 5 0mg·kg- 1)可以增强CHS反应。GCS(12 0和 2 4 0mg·kg- 1)连续灌胃 12d可以提升Cy增强的小鼠CHS胸腺T淋巴细胞中CD4 - CD8- 和CD4 +CD8- 细胞比例 ,降低CD4 +CD8+细胞比例 ;并提高胸腺淋巴细胞培养上清中IL 4水平 ,降低IL 2和TGF β1水平。结论　GCS对Cy增强的小鼠CHS有明显抑制作用 ;可有效调节小鼠胸腺CD4 /CD8和Th 淋巴细胞亚群及细胞因子产生平衡。