A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expre...A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expression in transgenic tobacco (Nicotiana tabacum L.) plants. Results from Western blot analysis of some of the transgenic tobacco plants showed that the expression level of GNA in plants transformed with the modified gene GNA34m reached 0.25% of total soluble proteins, while that of the GNA34 gene transgenic plants was 0.17%. Since the GNA expression level increased, the aphid resistance of GNA34m transgenic plants were also enhanced significantly as judged by a 71.0% aphid population inhibition in insect bioassay of GNA34m transformed plants and 63.7% for the plants transformed with the natural GNA34 gene.展开更多
Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the covera...Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway.展开更多
Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], ...Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.展开更多
Objective To study the co-effect of procyanidins extracted from the lotus seed pod (LSPC) and bilobalide (BIL) on ameliorating scopolamine-induced learning and memory impairment in young mice. Methods Fifty male K...Objective To study the co-effect of procyanidins extracted from the lotus seed pod (LSPC) and bilobalide (BIL) on ameliorating scopolamine-induced learning and memory impairment in young mice. Methods Fifty male Kunming mice with similar learning and memory capabilities were selected by Morris water maze test and were randomized into 5 groups (n=10 in each group): control group, scopolamine group, L-(LSPC+BIL) group (50 mg/kg LSPC+10 mg/kg BIL), M-(LSPC+BIL) group (100 mg/kg LSPC+20 mg/kg BIL), H-(LSPC+BIL) group (150 mg/kg LSPC+30 mg/kg BIL). Scopolamine model with impaired learning and memory was established by scopolamine treatment (1 mg/kg), and after 10 min mice were tested. In L-, M-, and H- (LSPC+BIL) groups, mice were treated with LSPC and BIL ig. for 30 days, while mice in the other 2 groups were treated with normal saline ig. instead. After the 30-day's treatment, the co-effect of LSPC and BIL on learning and memory was tested by Morris water maze and the step-down avoidance tests. Results The memory impairment caused by scopolamine in young mice could be ameliorated by co-treatment of LSPC and BIL, as indicated by significantly shorter escape latency and swimming distance in the Morris water maze test, when compared with those in the scopolamine group. In the step-down avoidance test, mice in all the 3 dose groups showed significantly smaller number of errors and longer latency than mice in the scopolamine group did. Conclusion Co-treatment of LSPE and BIL can ameliorate scopolamine-induced learning and memory impairment in young mice.展开更多
Doxorubicin is one of the anthracycline anti-neoplastic drugs widely used to treat leukemia, liver, breast, and ovarian cancers and other solid tumors. However, its clinical applications have been limited by its serio...Doxorubicin is one of the anthracycline anti-neoplastic drugs widely used to treat leukemia, liver, breast, and ovarian cancers and other solid tumors. However, its clinical applications have been limited by its serious cardio-cytotoxic effects. The aim of this study was to investigate the effect of neferine, a bisbenzylisoquinoline alkaloid extracted from the green embryo in the mature lotus seed, on the pharmacokinetics of doxorubicin. The levels of doxorubicin in plasma and tissues were measured using the high performance liquid chromatography(HPLC) method. The chromatographic separation was completed on a reversed-phase C18 column using acetonitrile–phosphate buffer(30:70, v/v) as the mobile phase at a flow rate of 1 mL /min and ultraviolet detection wave length was set at 233 nm. The pharmacokinetic study found that the co-administration of neferine and doxorubicin significantly affected the pharmacokinetics of doxorubicin. There were evident changes in area under the curve(AUC), clearance(CL) and t1/2β in group of pretreatment neferine as compared with those in group treated with doxorubicin alone. Tissue distribution analysis showed that the concentrations of doxorubicin distributed to heart, liver and kidney were statistically significant higher in group of pretreatment with neferine plus doxorubicin than those in the doxorubicin alone-group at 0.5 h and 2 h after drug administration, respectively. While the doxorubicin concentrations in spleen and lung drug were slightly increased in the group of pretreatment with neferine plus doxorubicin as compared to that of group of doxorubicin alone, the difference between two groups were not statistically significant. Therefore, the dose of doxorubicin needs to be taken into consideration when it is administrated in combination with neferine.展开更多
文摘A gene sequence coding for the precursor of Galanthus nivalis agglutinin (GNA) was modified by site-directed mutagenesis to change very low usage bias codons to higher usage bias ones for improvement of the gene expression in transgenic tobacco (Nicotiana tabacum L.) plants. Results from Western blot analysis of some of the transgenic tobacco plants showed that the expression level of GNA in plants transformed with the modified gene GNA34m reached 0.25% of total soluble proteins, while that of the GNA34 gene transgenic plants was 0.17%. Since the GNA expression level increased, the aphid resistance of GNA34m transgenic plants were also enhanced significantly as judged by a 71.0% aphid population inhibition in insect bioassay of GNA34m transformed plants and 63.7% for the plants transformed with the natural GNA34 gene.
文摘Angiosperms need light to synthesize chlorophyll, but lotus (Nelumbo nucifera Gaertn.) embryo was suspected to have the ability to form chlorophyll in the dark because lotus embryo can turn into green under the coverage of four layers of integuments (cotyledon, seed coat, pericarp, lotus pod) which were thought impossible for light to pass through. The authors excluded this possibility based on two experimental results: First, enclosing the young lotus pod with aluminium foil, the growth of louts embryo continued, but the chlorophyll formation was seriously inhibited. A lot of protochlorophyllide, chlorophyll precursor, were accumulated, most of which were combined with LPOR (light dependent protochlorophyllide oxidoreductase). Second, DPOR (dark or light-independent protochlorophyllide oxidoreductase) was the enzyme necessary for chlorophyll synthesis in the dark. The genes encoding DPOR were conservative in many species, but no homologues could be found in lotus genome. Taken together, authers' results clearly demonstrated that lotus embryo synthesizes chlorophyll only through the light-dependent pathway.
文摘Objective: To study the reversal effect of neferine on adriamycin (ADM) resistant human breast cancer cell line MCF-7/ADM. Methods: The cytotoxic effect of Nef or ADM was determined by 3-[4, 5-dimethylthiazol-2.-yl], 5-diphenyl tetraxolium bromid (MTT) assay. Apoptosis and the expression of P-glycoprotein (P-gp) were detected by flow cytometry (FCM). The intracellular ADM concentration was measured by HPLC. Results: Nef at 1, 5, 10 mol/L decreased the IC50 of ADM to MCF-7/ADM from 11.63 g/mL to 4.59, 2.44, 0.27 g/mL respectively. MCF-7/ADM could resist the apoptosis induced by ADM while Nef (1-10 mol/L) could augment ADR-mediated apoptosis. Nef (10 mol/L) increased the accumulation of ADM up to 2.88 fold in MCF-7/ADM but not in sensitive cells MCF-7/S and reduced the expression of P-gp in MCF-7/ADM cells. Conclusion: Nef can circumvent multidrug resistance (MDR) of MCF-7/ADM cells and the mechanism was associated with the increase of intracellular accumulation of ADM and the reduced expression of P-gp in MCF-7/ADM cells.
基金supported by the National Key Technology R&D Program of China (No.2006BAD27B08 and 2006BAD27B09-4)
文摘Objective To study the co-effect of procyanidins extracted from the lotus seed pod (LSPC) and bilobalide (BIL) on ameliorating scopolamine-induced learning and memory impairment in young mice. Methods Fifty male Kunming mice with similar learning and memory capabilities were selected by Morris water maze test and were randomized into 5 groups (n=10 in each group): control group, scopolamine group, L-(LSPC+BIL) group (50 mg/kg LSPC+10 mg/kg BIL), M-(LSPC+BIL) group (100 mg/kg LSPC+20 mg/kg BIL), H-(LSPC+BIL) group (150 mg/kg LSPC+30 mg/kg BIL). Scopolamine model with impaired learning and memory was established by scopolamine treatment (1 mg/kg), and after 10 min mice were tested. In L-, M-, and H- (LSPC+BIL) groups, mice were treated with LSPC and BIL ig. for 30 days, while mice in the other 2 groups were treated with normal saline ig. instead. After the 30-day's treatment, the co-effect of LSPC and BIL on learning and memory was tested by Morris water maze and the step-down avoidance tests. Results The memory impairment caused by scopolamine in young mice could be ameliorated by co-treatment of LSPC and BIL, as indicated by significantly shorter escape latency and swimming distance in the Morris water maze test, when compared with those in the scopolamine group. In the step-down avoidance test, mice in all the 3 dose groups showed significantly smaller number of errors and longer latency than mice in the scopolamine group did. Conclusion Co-treatment of LSPE and BIL can ameliorate scopolamine-induced learning and memory impairment in young mice.
基金The Scientific Research Fund Project of Heilongjiang University of Chinese Medicine(Grant No.201420)
文摘Doxorubicin is one of the anthracycline anti-neoplastic drugs widely used to treat leukemia, liver, breast, and ovarian cancers and other solid tumors. However, its clinical applications have been limited by its serious cardio-cytotoxic effects. The aim of this study was to investigate the effect of neferine, a bisbenzylisoquinoline alkaloid extracted from the green embryo in the mature lotus seed, on the pharmacokinetics of doxorubicin. The levels of doxorubicin in plasma and tissues were measured using the high performance liquid chromatography(HPLC) method. The chromatographic separation was completed on a reversed-phase C18 column using acetonitrile–phosphate buffer(30:70, v/v) as the mobile phase at a flow rate of 1 mL /min and ultraviolet detection wave length was set at 233 nm. The pharmacokinetic study found that the co-administration of neferine and doxorubicin significantly affected the pharmacokinetics of doxorubicin. There were evident changes in area under the curve(AUC), clearance(CL) and t1/2β in group of pretreatment neferine as compared with those in group treated with doxorubicin alone. Tissue distribution analysis showed that the concentrations of doxorubicin distributed to heart, liver and kidney were statistically significant higher in group of pretreatment with neferine plus doxorubicin than those in the doxorubicin alone-group at 0.5 h and 2 h after drug administration, respectively. While the doxorubicin concentrations in spleen and lung drug were slightly increased in the group of pretreatment with neferine plus doxorubicin as compared to that of group of doxorubicin alone, the difference between two groups were not statistically significant. Therefore, the dose of doxorubicin needs to be taken into consideration when it is administrated in combination with neferine.