Role of extracellular signal-regulated kinase in regulating expression of interleukin 13 in lymphocytes from an asthmatic rat model

Background The extracellular signal-regulated kinase （ERK） is widely expressed in mammal cells and involved in airway proliferation and remodeling in asthma. In this study, we intend to explore the role of ERK in the expression of the Th2 cytokine, interleukin 13 （IL-13） in lymphocytes in asthma. Methods Forty Sprague-Dawley rats were randomly divided into two groups： normal control and asthmatic groups. Peripheral blood lymphocytes were isolated and purified from the blood of each rat and divided into five groups： control, asthmatic lymphocytes, asthmatic cells stimulated with ERK activator epidermal growth factor （EGF）, or with ERK inhibitor PD98059, or with EGF and PD98059 together. The expression of phosphorylated-ERK （p-ERK） was observed by immunocytochemical staining, the expression of ERK mRNA was determined by reverse transcriptase-PCR, IL-13 protein in supernatants was measured by ELISA. Results （1） The ERK mRNA level and the percentage of cells with p-ERK in lymphocytes from asthmatic rats were significantly higher than those in normal controls, and were significantly increased by EGF administration. This effect of EGF was significantly inhibited by PD98059 pretreatment. （2） IL-13 protein in supernatants of asthmatic lymphocytes was higher than that produced by normal control lymphocytes, and was significantly increased by EGF treatment. This EGF effect was partly blocked by PD98059 pretreatment. （3） There was a significant positive correlation between the percentage of cells with p-ERK in peripheral blood lymphocytes and IL-13 protein in supernatants of lymphocytes from asthmatic rats. Conclusions In asthma the ERK expression and activation levels were increased, as was the protein level of IL-13. The ERK signaling pathway may be involved in the increased expression of the Th2 cytokine IL-13 in asthma.

Runjing extract promotes spermatogenesis in rats with ornidazole-induced oligoasthenoteratozoospermia through extracellular signal-regulated kinase signalling,and regulating vimentin expression

OBJECTIVE:To investigate the efficacy of Runjing(RJ)extract on oligoasthenoteratozoospermia(OAT)induced by ornidazole(ORN)in rats,and to study the underlying mechanism.METHODS:Twenty-four adult male Sprague-Dawley rats were treated with normal saline(control),ORN(OAT model),ORN+4.725 g-dose)and ORN+18.9 g·kg^(-1)·d^(-1) RJ extract(low·kg^(-1)·d^(-1) RJ extract(high-dose)for 4 weeks.The rats were then euthanized and sperm and testis samples were collected for analysis.Sperm count,motility and morphology were calculated by sperm suspension from cauda epididymis.Testicular histopathological changes were analyzed by hematoxylin and eosin staining and Td T mediated d UTP nick end labelling.Moreover,the expression of vimentin and extracellular signal-regulated kinase(ERK)were examined through Western blot,and the distribution of vimentin was detected via immunohistochemistry.RESULTS:ORN successfully induces seminiferous epithelium injury,cellular apoptosis,and finally OAT(P<0.05).However,both low-dose and highdose RJ extract partially rescues the altered phenotypes(P<0.05).Moreover,the expressions of vimentin and ERK were significantly altered in ORN testes(all P<0.001),while RJ extract partially reversed these effects(P<0.01 or P<0.001).CONCLUSION:RJ extract can help maintain spermatogenesis through ERK signalling,and regulating vimentin expression.

Extracts from Huangqi(Radix Astragali Mongoliciplus) and Ezhu(Rhizoma Curcumae Phaeocaulis) inhibit Lewis lung carcinoma cell growth in a xenograft mouse model by impairing mitogen-activated protein kinase signaling, vascular endothelial growth factor prod

OBJECTIVE: To study the anti-tumor effects of the extracts from Huangqi(Radix Astragali Mongolici)and Ezhu(Rhizoma Curcumae Phaeocaulis) on the growth of Lewis lung carcinoma(LLC) in a xenograft mouse model and to investigate the possible underlying mechanism.METHODS: LLC tumor-bearing C57 BL/6 mice were treated with normal saline, cisplatin(2 mg/kg intraperitoneally every other day), or Huangqi(Radix Astragali Mongolici) and Ezhu(Rhizoma Curcumae Phaeocaulis)(1∶1, 2∶1, or 3∶1 ratio;5, 8, or 11 g/kg crude drug intragastrically every day) for 15 d.Body weights and tumor volumes were measured every other day. Tumors were excised on day 15 and analyzed. Tumor microvessel density(MVD)was assessed by immunohistochemical staining of CD34;and expression of vascular endothelial cell growth factor(VEGF), the mitogen-activated protein kinases p38 mitogen-activated protein kinase(MAPK), extracellular signal-regulated kinases 1 and 2(ERK1/2), and Jun N-terminal kinase(JNK)and their phosphorylated forms were assessed by Western blotting.RESULTS: Treatment with cisplatin caused a significant loss of body weight compared with controls,whereas Huangqi(Radix Astragali Mongolici) and Ezhu(Rhizoma Curcumae Phaeocaulis) extract combinations had no effect. Extracts from Huangqi(Radix Astragali Mongolici) and Ezhu(Rhizoma Curcumae Phaeocaulis) significantly decreased tumor weight and tumor MVD compared with controls,and at the 3∶1 treatment group had similar efficacy to cisplatin in reducing MVD. Tumors from Huangqi(Radix Astragali Mongolici) and Ezhu(Rhizoma Curcumae Phaeocaulis) treatments also showed decreased p38 MAPK, p-p38 MAPK, ERK1/2, p-ERK1/2,JNK, and p-JNK expression compared with the control group(all P < 0.01). VEGF protein expression was significantly reduced in the 2∶1 and 3∶1 treatment groups compared with the control group(P < 0.01).CONCLUSION: Extracts from Huangqi(Radix Astragali Mongolici) and Ezhu(Rhizoma Curcumae Phaeocaulis) hindered LLC growth in the xenograft mouse model, possibly via inhibition of the MAPK signaling pathway, VEGF production, and tumor angiogenesis.

脊髓NO信号通路和ERK信号通路在吗啡依赖大鼠戒断反应中的作用

目的评价脊髓NO信号通路和细胞外调节激酶（ERK）信号通路在吗啡依赖大鼠戒断反应中的作用。方法鞘内置管成功的健康雄性SD大鼠90只，体重200-250g，采用随机数字表法，将其随机分为9组（n=10）：正常对照组（C组）、吗啡依赖组（MD组）、吗啡戒断组（MW组）、L-N-硝基精氨酸甲酯组（L-NAME组）、7-硝基吲唑组（7-Ni组）、氨基胍组（AG组）、U0126组、克列莫佛组（cremo．phor组）和二甲基亚砜组（DMSO组）。MD组、MW组、L-NAME组、7-Ni组、AG组、U0126组、cremophor组和DMSO组皮下注射吗啡10ms／ks，2次，d，隔天每次增加10mg／kg，至第6天末次注射50ms／kg，建立吗啡依赖模型。末次注射吗啡后4h时，MW组、L-NAME组、7-Ni组、AG组、150126组、cremophor组和DMSO组腹腔注射纳洛酮4ms／kg激发吗啡戒断反应。给予纳洛酮前30min时，L-NAME组、7-Ni组、AG组、U0126组、cremophor组和DMSO组分别鞘内注射L广N．硝基精氨酸甲酯400／Lg（溶于10出生理盐水中）、7-硝基吲唑400btg（溶于10pl克列莫佛中）、氨基胍400tLg（溶于10出生理盐水中）、U0126150ttg（溶于10出二甲基亚砜中）、克列莫佛10肛l和二甲基亚砜10μl。注射纳洛酮后1h内观察大鼠戒断反应和痛觉异常反应，并进行评分，然后处死大鼠，取脊髓组织，分别采用免疫组化法和Western blot法测定脊髓背角诱导型一氧化氮合酶（iNOS）、神经型一氧化氮合酶（nNOS）和磷酸化ERK（p-ERK）的表达。结果与MD组比较，Mw组、L-NAME组、7-Nj组、AG组、U0126组、DMS0组和cremophor组戒断反应评分和促诱发痛评分升高（P〈0．05）；与MW组比较，L-NAME组、7-Ni组、AG组和U0126组戒断反应评分和促诱发痛评分降低（P〈0．05），DMSO组和cremophor组差异无统计学意义（P〉0．05）；与C组和MD组比较，MW组脊髓背角nNOS和iNOS表达上调（P〈0．05）；与MW组比较，U0126组脊髓背角nNOS和iNOS表达下调（P〈0．05）。与c组比较，MD组和MW组脊髓背角p-ERK表达上调（P〈0．05）；与MW组比较，L-NAME组、7-Ni组和AG组脊髓背角p-ERK表达下调（P〈0．05）。结论脊髓NO信号通路和ERK信号通路的相互调节作用参与了吗啡依赖大鼠的戒断反应。