Antioxidant activities of aqueous leaf extracts of Toona sinensis on free radical-induced endothelial cell damage

Ethnopharmacological relavence

In Taiwan, Toona sinensis (Toona sinensis) is well known as a traditional Chinese medicine, while the underlying pharmacological mechanisms of this drug are still a matter of debate.

Materials and methods

The purpose of this study was to evaluate the protective effects of non-cytotoxic concentrations of aqueous leaf extracts of Toona sinensis (TS extracts; 50-100 μg/mL) and gallic acid (5 μg/mL), a major component of these extracts, against AAPH-induced oxidative cell damage in human umbilical vein endothelial cells (ECs).

Results

Exposure of ECs to AAPH (15 mM) decreased cell viability from 100% to 43%. However, ECs were pre-incubated with TS extracts prior to AAPH induction resulted in increased resistance to oxidative stress and cell viability in a dose-dependent manner. An increase in ECs-derived PGI₂ and IL-1β in response to AAPH exposure was positively correlated with cytotoxicity and negatively with TS extracts concentrations. In addition, gallic acid also suppressed PGI₂ and IL-1β production in AAPH-induced ECs. Notably, TS extracts/gallic acid treatment significantly inhibited ROS generation, MDA formation, SOD/catalase activity, and Bax/Bcl-2 dysregulation in AAPH-stimulated ECs. Pretreatment of ECs with TS extracts/gallic acid also suppressed AAPH-induced cell surface expression and secretion of VCAM-1, ICAM-1 and E-selectin, which was associated with abridged adhesion of U937 leukocytes to ECs. Moreover, TS extracts/gallic acid treatment significantly inhibited the AAPH-mediated up regulation of PAI-1 and down regulation of t-PA in ECs, which may decrease fibrinolytic activity.

Conclusions

Therefore, Toona sinensis may possess antioxidant properties that protect endothelial cells from oxidative stress. Our results also support the traditional use of Toona sinensis in the treatment of free radical-related diseases and atherosclerosis.     

Protective effect of Ilex latifolia, a major component of "kudingcha", against transient focal ischemia-induced neuronal damage in rats

Aims of the study

Ilex latifolia (Aquifoliaceae), a primary component of “kudingcha”, has been used in Chinese folk medicine to treat various kinds of diseases including headaches, inflammatory diseases, and cardiac ischemic injury. The present study investigated the protective effect of the ethanol extract of Ilex latifolia against transient, focal, ischemia-induced neuronal damage.

Materials and methods

Transient focal ischemia was induced by 2 h middle cerebral artery occlusion followed by 24 h reperfusion (MCAO/reperfusion) in rats. After MCAO/reperfusion, brain infarction and neuronal death were measured by triphenyltetrazolium chloride and hematoxylin and eosin staining, respectively. Glutathione concentration and lipid peroxidation rate were measured. The expression levels of phosphorylated mitogen activated proteins kinases (MAPKs), cyclooxygenase 2 (COX-2), and anti-apoptotic and pro-apoptotic proteins were detected by Western blot.

Results

Ilex latifolia (50-200 mg/kg) significantly reduced MCAO/reperfusion-induced infarction and edema formation, neurological deficits, and brain cell death. Depletion of glutathione level and lipid peroxidation induced by MCAO/reperfusion were inhibited by administration of Ilex latifolia. The increase of phosphorylated MAPKs, COX-2, and proapoptotic proteins and the decrease of antiapoptotic protein in MCAO/reperfusion rats were significantly inhibited by treatment with Ilex latifolia.

Conclusion

Ilex latifolia ameliorated ischemic injury induced by MCAO/reperfusion in rats, and this neuroprotective effect might be associated with its anti-apoptotic effect, resulting from anti-oxidative and anti-inflammatory actions.     

舒脉宁注射液对大鼠脑缺血再灌注损伤保护作用的实验研究

[目的]探讨舒脉宁注射液(SHUMN)对脑缺血再灌注损伤的保护作用。[方法]采用大鼠全脑缺血再灌注损伤模型,观察脑缺血前后血浆一氧化氮(NO)、内皮素(ET)和脑组织钙及含水量的变化。[结果]脑缺血再灌注期血浆NO、ET和脑组织钙及含水量显著升高(P<0.05),使用舒脉宁注射液后,血浆NO、ET和脑组织钙及含水量明显降低。[结论]舒脉宁注射液对脑缺血再灌注损伤确有保护作用。     

蜈蚣对心肌缺血性损伤小鼠NO及iNOS的影响

目的 :探讨中药蜈蚣对心肌缺血性损伤小鼠一氧化氮 (NO)及一氧化氮合酶 (i NOS)的影响。方法 :采用脑垂体后叶素造成小鼠心肌缺血性损伤模型。将健康小鼠分为四组 ,分别是空白组、模型组、蜈蚣小剂量组(2 .5 g/ kg)、蜈蚣大剂量组 (5 .0 g/ kg)。缺血 2 0 m in后取血观察乳酸脱氢酶 (L DH ) ,检测心肌组织一氧化氮 (NO) ,免疫组化法检测心肌一氧化氮合酶 (i NOS)。结果 :蜈蚣治疗后 L DH降低 ,NO、i NOS明显升高。结论 :蜈蚣可显著提高 NO及 i NOS的表达 ,这可能与蜈蚣保护血管内皮细胞功能有关。     

竹节参总皂苷对脑缺血损伤大鼠海马一氧化氮合酶的影响

目的:探讨竹节参总皂苷(tRPJS)对脑缺血损伤的保护作用机制,观察药物对局灶性脑缺血大鼠和慢性前脑缺血大鼠海马组织一氧化氮合酶(NOS)及诱导型一氧化氮合酶(iNOS)的影响。方法:采用线栓法建立局灶性脑缺血大鼠模型,双侧颈总动脉永久结扎方法制备慢性前脑缺血,研究竹节参总皂苷对这两种脑缺血损伤大鼠模型海马组织NOS,iNOS的影响。结果:与假手术组相比,局灶性脑缺血大鼠海马组织NOS,iNOS含量均明显增高(P<0.05),竹节参总皂苷能显著降低局灶性脑缺血大鼠NOS,iNOS的含量(P<0.05);慢性前脑缺血大鼠与假手术组相比,海马组织总NOS活力没有明显改变,iNOS含量增高(P<0.05),竹节参总皂苷能显著降低慢性前脑缺血大鼠海马组织iNOS的含量(P<0.05)。结论:竹节参总皂苷抗缺血性海马神经元损伤与降低海马组织iNOS的活性有关。     

Evaluation of the anti-inflammatory and anti-proliferation tumoral cells activities of Antrodia camphorata, Cordyceps sinensis, and Cinnamomum osmophloeum bark extracts

The extracts of chloroform (1) and methanol (2) from Antrodia camphorata (AC), and chloroform (3) and n-butanol (4) fractions of methanol extract from Cordyceps sinensis (CS), and hexane (5), ethyl acetate (6), and methanol (7) from Cinnamomum osmophloeum bark (CO) were evaluated for their anti-inflammatory as well as tumor-cell growth inhibitory activities in vitro. All the tested extracts dose dependently inhibited the enhanced production of inflammatory mediators such as nitric oxide (NO) through reducing inducible NO synthase expression, and cytokines (tumor necrosis factor (TNF)-alpha and interleukin (IL)-12 in LPS/IFN-gamma activated murine peritoneal macrophages. In addition, extracts 1 from AC, and 5 and 6 from CO significantly arrest the mitogen-stimulated spleen cells in G0/G1 stage. On the other hand, all these extracts were also evaluated for their tumor-cell proliferation activities in different type of cancer cell lines such as Jurkat, HepG2, PC 3, Colon 205, and MCF 7 as well as normal PBMCs. Compared to untreated controls, the extracts 1, 2, and 4-7 were most active and inhibited Jurkat cells with IC50 value of 22, 40, 18, 4, 5, and 45 microg/ml, respectively. In addition, the extracts 5, 6, and 7 from CO showed potent growth inhibition of HepG2 and PC 3 with IC50 values of 35, 80, 55 microg/ml; and 42, 125, and 50 microg/ml, respectively. Similarly, the extracts 1 and 5 inhibited the growth of Colon 205 and MCF 7 cells with IC50 values of 65, 33; and 95 and 30 microg/ml, respectively. Interestingly, none of the tested extract has shown cytotoxicity towards normal PBMCs up to the concentration range studies (0-150 microg/ml). Taken together, these data suggest that the anti-inflammatory and anti-cancer properties of AC, CS, and CO might result from the growth inhibition of NO, TNF-alpha and IL-12, and tumor cells proliferation, respectively.     

Studies of biological properties of Uncaria tomentosa extracts on human blood mononuclear cells

Ethnopharmacological relevance

Uncaria tomentosa (Willd.) DC is a lignified climbing plant from South and Central America, which (under the name of “vilcacora” or “cat's claw”) has become highly popular in many countries due to its proven immunostimmulatory and anti-inflammatory activities and also with respect to its anticancer and antioxidative effects. There are insufficient data on the mechanism of U. tomentosa action on normal blood mononuclear cells.

Aim of the study

The aim of the study was to analyze the impact of ethanol and aqueous extracts from bark and leaves of Uncaria tomentosa on the structure and function of human mononuclear cells and to find out whether the kind of extractant used modulates biological activity of the extracts studied.

Materials and methods

Plant material consisted of four different extracts: (1) ethanol extract from leaves, (2) aqueous extract from leaves, (3) ethanol extract from bark and (4) aqueous extract from bark. The effect of these extracts on protein damage as well as on free-radical formation in human peripheral blood mononuclear cells was analyzed. Moreover, changes in viability, size, and granularity as well as apoptotic alterations in human blood mononuclear cells exposed to U. tomentosa extracts were investigated.

Results

The oxidative changes were observed in mononuclear blood cells exposed to both ethanol and aqueous extracts obtained from bark and leaves. Moreover, in the cells studied the extracts from U. tomentosa induced apoptosis and a decrease in viability of mononuclear blood cells, with the exception of aqueous extract from leaves. Additionally, no statistically significant changes in the cell size were observed both for aqueous extracts from leaves and bark. Changes in the blood mononuclear cell granularity were observed at 250 μg/mL for all extracts examined. The strongest changes were observed for the ethanol extract of the bark, which increased cell granularity at 50 μg/mL and changed cell size at 100 μg/mL.

Conclusion

The conducted research showed differences in biological activity between aqueous and ethanol extracts. It was observed that ethanol extracts exhibited stronger negative effects on mononuclear blood cells. The kind of extractant used had a significant influence of the chemical composition of the tested extracts. The ethanol extract from bark containing a high amount of polyphenols and alkaloids revealed the highest pro-apoptotic effect.     

Protective effect of Acanthopanax senticosus extract against endotoxic shock in mice

AIM OF THE STUDY: In this study, we evaluated protective effect of Acanthopanax senticosus extract (ASE) and a possible signaling pathway involved during endotoxic shock induced by intraperitoneal injection lipopolysaccharide (LPS) and D-galactosamine (D-GalN) in BALB/c mice. MATERIALS AND METHODS: Mice were intraperitoneal administrated with ASE (100, 200 or 400mg/kg) prior to injection of 50 microg/kg LPS and 1g/kg D-GalN. The levels of tumor necrosis-alpha (TNF-alpha) and interleukin-10 (IL-10) in serum and liver. Nitric oxide (NO) production in serum and inducible nitric oxide synthase (iNOS) protein level were investigated. Nuclear factor-kappa B (NF-kappaB) activation in liver was determined. Furthermore, we evaluated the effect of ASE pretreatment on infiltration of inflammatory cells into the heart, liver and lung of mice. RESULTS: Treatment of mice with ASE prior to LPS/D-GalN injection significantly improved the survival rate. ASE pretreatment inhibited the elevation of TNF-alpha in serum and liver. ASE also decreased iNOS level in liver and the overproduction of nitric oxide (NO) in serum. In addition, IL-10 levels in serum and liver were markedly enhanced. ASE pretreatment inhibited NF-kappaB activation in liver of mice. Moreover, infiltration of inflammatory cells into the heart, liver and lung of mice was also attenuated by ASE pretreatment. CONCLUSIONS: These results suggested that ASE protected mice against LPS/D-GalN-induced endotoxic shock involving inhibition of NF-kappaB activation, which caused down-regulation of TNF-alpha and involved up-regulation of IL-10. Acanthopanax senticosus may thus prove beneficial in the prevention of endotoxic shock.     

绞股蓝总皂苷对大鼠局灶性脑缺血再灌注损伤的保护作用

目的 观察绞股蓝总皂苷对大鼠急性局灶性脑缺血再灌损伤NO的保护作用。方法 采用大脑中动脉内栓线阻断不（MCAO）造成大鼠局灶性脑缺血再灌注模型，测定脑亚细胞器内NO含量的变化并观察病理组织学变化。脑缺血再灌注后脑亚细胞器内NO含量显著升高，海马CA1区存活的锥体细胞数显著降低。绞股蓝总皂苷能显著降低脑亚细胞器内NO含量，升高海马CA1区存活的锥体细胞数。结论 论股蓝总皂苷通过降低NO的毒性，发挥保护脑组织，减轻缺血再灌注损伤。     

Immunostimulatory effects of Uncaria perrottetii (A. Rich.) Merr. (Rubiaceae) vinebark aqueous extract in Balb/C mice

Aims of the study

Crude extract of Uncaria perrottetii (A. Rich.) Merr. vinebark was evaluated for its immunomodulating activity in Balb/C mice. Initially, the immunomodulatory potential of the plant extract was evaluated using in vitro immune response assays at different concentrations of the plant extract (10 μg/mL, 20 μg/mL, 50 μg/mL and 100 μg/mL). Using the optimum concentration determined in the in vitro assays, the protective effect of the plant extract was assessed against drug-induced immunosuppression in vivo.

Materials and Methods

For the in vivo experiment, thirty-six (36) mice were divided into 3 groups of 12 mice each: (1) cyclophosphamide drug-induced (30 mg/kg BW) immunosuppressed mice (Cy group) served as the positive control; (2) Uncaria perrottetii extract and Cy-treated mice (U + Cy); and (3) PBS-injected mice as the negative control group [(−) CTRL].

Results

The optimum concentration was determined to be 50 μg/mL in the in vitro assays. At this concentration, Uncaria perrottetii extract stimulated peritoneal phagocyte activation, produced a significant increase in the activity of phagocytic cells from the spleen and promoted splenic cellular proliferation with or without lipopolysaccharide (LPS) when compared with the PBS-treated cells (negative control). Moreover, cells treated with 50 μg/mL of Uncaria perrottetii increased macrophage respiratory burst activity that was comparable to that of the phorbol myristate acetate-stimulated splenic macrophages.In all immune assays undertaken in the in vivo experiment, the Cy-treated mice showed significantly lower response when compared with the PBS-treated mice. Significant improvement in peritoneal cell activation, phagocytic activity and cellular proliferation was exhibited by the U + Cy-treated mice when compared with Cy-injected mice. The extract from Uncaria perrottetii also significantly enhanced respiratory burst and plasma lysozyme activity compared with the Cy-injected mice.

Conclusions

Based on the results of both in vitro and in vivo trials, Uncaria perrottetii extract has immunopotentiating activities on the innate immunity of Balb/C mice and the extract could potentially reverse the immunosuppressive effects of Cy. However, the potential of the plant as source of bioactive products and metabolites for drug development still has to be fully investigated.     

Anti-influenza virus activity of Chaenomeles sinensis

AIM OF THE STUDY: This investigation evaluated anti-influenza virus activity of 50% ethanol extract of the fruit of Chaenomeles sinensis K(OEHNE), which is widely used as a traditional Chinese medicine to treat throat diseases. MATERIAL AND METHODS: Type A and B influenza viruses were treated with the extract at various concentrations for 1h at room temperature; then the plaque titers of the treated viruses were determined. The neutralizing component in the extract was partially purified using HP20 column chromatography. RESULTS: Treatment with the extract at concentrations greater than 5mg/ml reduced the plaque titers of the both viruses to less than 10% of those of untreated viruses. The treatment inhibited viral hemagglutination activity, too. When the 50mg/ml extract was added to the culture medium after inoculation of the virus, viral NS2 protein synthesis was selectively inhibited and progeny virus was not detected in the infected cell medium. Partial purification showed that the neutralizing component consisted of high molecular weight polyphenols. CONCLUSION: High molecular weight polyphenols in the fruits of C. sinensis neutralizes influenza virus by inhibiting hemagglutination activity and by suppressing NS2 protein synthesis.     

黄蜀葵总黄酮对心脑缺氧损伤的保护作用

目的 :研究黄蜀葵总黄酮 (TFA)对心脑缺氧性损伤的保护作用。方法 :小鼠心脑缺氧模型分别采用断头和挟闭气管术制备 ,一氧化氮 (NO)含量用 green法测定 ,丙二醛 (MDA)含量用 TAB法测定 ,结果 :TFA2 0、40、80 mg.kg-1显著延长挟闭气管后小鼠心电图的时间和断头后喘气时间 ,并呈量效关系 ,在 2 0～ 80 mg.kg-1范围内 ,黄蜀葵总黄酮显著降低心脑组织中 MDA和 NO含量。结论 :TFA对心脑缺氧有显著保护作用 ,其作用可能与抗自由基及减少 NO有关     

Gleditsia sinensis thorns inhibit the production of NO through NF-kappaB suppression in LPS-stimulated macrophages

The thorns of Gleditsia sinensis LAM. (Leguminosae) have been used in traditional medicine for the treatment of inflammatory diseases including swelling, suppuration, carbuncle and skin diseases in China and Korea. In this study, we investigated the mechanism responsible for anti-inflammatory effects of Gleditsia sinensis thorns in RAW 264.7 macrophages. The aqueous extract of Gleditsia sinensis thorns (AEGS) inhibited LPS-induced NO secretion as well as inducible nitric oxide synthase (iNOS) expression, without affecting cell viability. Furthermore, AEGS suppressed LPS-induced NF-kappaB activation, phosphorylation and degradation of IkappaB-alpha, phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and c-Jun N-terminal kinase (JNK). These results suggest that AEGS has the inhibitory effects on LPS-induced NO production and iNOS expression in macrophages through blockade in the phosphorylation of MAPKs, following IkappaB-alpha degradation and NF-kappaB activation.     

Treatment of THP-1 cells with Uncaria tomentosa extracts differentially regulates the expression if IL-1beta and TNF-alpha

Uncaria tomentosa, commonly known as cat's claw, is a medicinal plant native to Peru, which has been used for decades in the treatment of various inflammatory disorders. Uncaria tomentosa can be used as an antioxidant, has anti-apoptotic properties, and can enhance DNA repair, however it is best know for its anti-inflammatory properties. Treatment with Uncaria tomentosa extracts inhibits the production of the pro-inflammatory cytokine, TNF-alpha, which is a critical mediator of the immune response. In this paper, we showed that treatment of THP-1 monocyte-like cells with Uncaria tomentosa extracts inhibited the MAP kinase signaling pathway and altered cytokine expression. Using ELISA assays, we showed that treatment with Uncaria tomentosa extracts augmented LPS-dependent expression of IL-1beta by 2.4-fold, while inhibiting the LPS-dependent expression of TNF-alpha by 5.5-fold. We also showed that treatment of LPS-stimulated THP-1 cells with Uncaria tomentosa extracts blocked ERK1/2 and MEK1/2 phosphorylation in a dose-dependent manner. These data demonstrate that treatment of THP-1 cells with Uncaria tomentosa extracts has opposite effects on IL-1beta and TNF-alpha secretion, and that these changes may involve effects on the MAP kinase pathway.     

氧化槐定碱对小鼠急性脑缺血损伤的保护作用

目的:研究氧化槐定碱(Oxysophoridine,OSR)对小鼠脑组织急性缺血的保护作用。方法:ICR小鼠50只随机分为5组:对照组;OSR(62.51,25,250 mg/kg)组;尼莫地平(20mg/kg)组。各实验组分别灌胃7d,1次/d;对照组给予相同容积的生理盐水。末次给药后1小时,采用快速断头法制备小鼠急性全脑缺血模型。观察小鼠的喘息次数和喘息维持时间;取小鼠脑组织测定丙二醛(MDA)的含量和超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、乳酸脱氢酶(LDH)、肌酸激酶(CK)以及一氧化氮合酶(NOS)的活性。结果:与对照组比较,OSR(125、250mg/kg)组和尼莫地平(20mg/kg)组小鼠断头后喘息次数明显增加,喘息维持时间显著延长;与对照组比较,OSR(62.51、25、250mg/kg)组和尼莫地平(20mg/kg)组小鼠脑组织MDA含量明显降低;与对照组比较,OSR(1252、50mg/kg)组和尼莫地平(20mg/kg)组小鼠脑组织SOD、GSH-Px活性显著增高;与对照组比较,OSR(125、250mg/kg)组和尼莫地平(20mg/kg)组小鼠脑组织LDH、CK活性明显增高;与对照组比较,OSR(1252、50mg/kg)组和尼莫地平(20mg/kg)组小鼠脑组织NOS活性显著降低。结论:氧化槐定碱对小鼠急性脑缺血损伤有明显的保护作用,其作用机制可能与其抗氧化作用有关。     

Involvement of heme oxygenase-1 in the anti-inflammatory activity of Chrysanthemum boreale Makino extracts on the expression of inducible nitric oxide synthase in RAW264.7 macrophages

Aim of the study

This study is to elucidate the involvement of anti-inflammatory heme oxygenase-1 (HO-1) in the inhibitory activity of a Chrysanthemum boreale Makino (CB) extract on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.

Materials and methods

Cell viability and NO assay were performed. In addition, iNOS expression was detected by Western blotting and real-time PCR. HO-1 expression was also evaluated by Western blotting, and blocking HO-1 activity on NO production was performed.

Results

The CB extract at the highest concentration (100 μg/ml) significantly inhibited NO production by approximately 90% and suppressed iNOS protein expression by approximately 84.8% compared to LPS-stimulated cells. Furthermore, the CB extract (100 μg/ml) inhibited iNOS mRNA expression in a concentration-dependant manner and suppressed iNOS mRNA expression by 94.8%. The CB extract induced the expression of HO-1 in a dose-dependent manner, and blocking HO-1 activity abolished the inhibitory effects of the CB extract. Moreover, the addition of carbon monoxide such as tricarbonyl dichlororuthenium (II) dimmer (RuCO), a byproduct derived from heme degradation, mimicked the inhibitory action of low concentrations of CB extract.

Conclusion

These results suggest that a CB extract has potent anti-inflammatory activity in RAW264.7 macrophages involving the induction of HO-1.     

喜脑宁对大鼠全脑缺血的保护作用及机制研究

目的:探讨喜脑宁冻干粉(XNN)对全脑缺血的保护作用及其可能机制.方法:采用四动脉结扎法建立大鼠全脑缺血/再灌注模型,观察XNN对脑缺血再灌注过程中脑电图及翻正反射恢复时间、脑含水量、脑指数、脑组织匀浆MDA和LD含量、SOD,LDH和NOS活性、海马ET含量的影响;观察XNN对ADP诱导的血小板聚集率的影响;采用Fura-2/AM负载法,观察XNN对血小板内静息[Ca~(2+)]_i;和CaCl_2诱导血小板内[Ca~(2+)]_i,浓度变化的影响.结果:在全脑缺血再灌注模型上,XNN可以缩短翻正反射恢复时间,促进脑电图的恢复;降低脑含水量、脑指数;提高脑组织SOD,LDH活性,降低LD,MDA含量和NOS活性;降低海马组织ET含量.XNN对ADP诱导的血小板聚集有一定的抑制作用,能降低血小板内静息期[Ca~(2+)]_i,并对CaCl_2诱导的血小板内[Ca~(2+)]_i的升高有抑制作用.结论:XNN对全脑缺血具有一定的保护作用.     

Investigation of plant extracts in traditional medicine of the Brazilian Cerrado against protozoans and yeasts

Aim of the study

To investigate the activities of the 217 plant extracts in traditional medicine of the Brazilian Cerrado against protozoans and yeasts.

Materials and methods

Plant extracts were prepared by the method of maceration using solvents of different polarities. The growth inhibition of chloroquine-resistant Plasmodium falciparum strain (FcB1) was determined by measuring the radioactivity of the tritiated hypoxanthine incorporated. Activity against Leishmania (Leishmania) chagasi and Trypanosoma cruzi was measured by the MTT colorimetric assay. The antifungal tests were carried out by using the CLSI method. The active extracts were tested also by cytotoxicity assay using NIH-3T3 cells of mammalian fibroblasts.

Results

Two hundred and seventeen extracts of plants were tested against Plasmodium falciparum. The eleven active extracts, belonging to eight plant species were evaluated against L. (L.) chagasi, Trypanosoma cruzi, yeasts and in NIH-3T3 cells. The results found in these biological models are consistent with the ethnopharmacological data of these plants. The ethyl acetate extract of Diospyros hispida root showed IC₅₀ values of 1 μg/mL against Plasmodium falciparum. This extract demonstrated no toxicity against mammalian cells, resulting in a significant selectivity index (SI) of 435.8. The dichloromethane extract of Calophyllum brasiliense root wood was active against Cryptococcus gattii LMGO 01 with MIC of 1.95 μg/mL; and Candida albicans ATCC 10231 and Candida krusei LMGO 174, both with MIC of 7.81 μg/mL. The same extract was also active against Plasmodium falciparum and L. (L.) chagasi with IC₅₀ of 6.7 and 27.6 μg/mL respectively. The ethyl acetate extract of Spiranthera odoratissima leaves was active against Cryptococcus gattii LMGO 01 with MIC of 31.25 μg/mL, and against Plasmodium falciparum with IC₅₀ of 9.2 μg/mL and Trypanosoma cruzi with IC₅₀ of 56.3 μg/mL.

Conclusion

The active extracts for protozoans and human pathogenic yeasts are considered promising to continue the search for the identification and development of leading compounds.     

白木香查尔酮合酶基因的克隆和生物信息学分析

目的:对国产沉香的源植物白木香Aquilaria sinensis查尔酮合酶(chalcone synthase,CHS)基因AsCHS1编码区进行克隆,并对其进行生物信息学分析和表达分析。方法:根据已报道的白木香伤害转录组高通量测序结果分析获得1条具有查尔酮合酶保守结构域的CHS基因序列,采用RT-PCR技术,以不同伤害时间白木香木质部混合样品总RNA为模板克隆得到白木香AsCHS1的基因编码区序列,并对AsCHS1蛋白进行理化性质、蛋白二级结构及三维结构预测分析。另外,采用qRT-PCR方法,以组蛋白(histones)为内参对AsCHS1基因在伤害胁迫下的表达模式进行分析。结果:序列分析表明,所克隆的AsCHS1基因编码区开放阅读框(opening reading frame,ORF)长为1 194 bp,编码397个氨基酸残基,命名为AsCHS1。qRT-PCR实验证明该基因表达量在伤害后12 h最大,说明该基因能够在早期响应伤害胁迫。结论:白木香AsCHS1基因的编码区序列的分离克隆为进一步研究AsCHS1蛋白在白木香中黄酮合成途径中的功能及表达调控奠定基础。