Cytotoxic clerodane diterpenoids from the leaves of Premna tomentosa

Three clerodane diterpenoids, premnones A-C (1-3), were isolated from a chloroform-soluble fraction of Premna tomentosa along with four known flavonoids and three known triterpenoids. Among these isolates, premnones A-C exhibited cytotoxic activity when evaluated against a small panel of tumor cell lines. However, premnone A was found to be inactive when evaluated in a follow-up in vivo hollow fiber assay at the highest dose tested (50mg/kg), using LNCaP, Lu1, and MCF-7 cells.     

Effect of Sargassum polycystum (Phaeophyceae)-sulphated polysaccharide extract against acetaminophen-induced hyperlipidemia during toxic hepatitis in experimental rats

The effect of Sargassum polycystum crude extract on lipid metabolism was examined against acetaminophen-induced (800 mg/kg body wt., intraperitoneally) hyperlipidemia during toxic hepatitis in experimental rats. The animals intoxicated with acetaminophen showed significant elevation in the levels of cholesterol, triglycerides and free fatty acid in both serum and liver tissue. The levels of tissue total lipids and serum LDL-cholesterol were also elevated with depleted levels of serum HDL-cholesterol and tissue phospholipid. The acetaminophen-induced animals showed significant alterations in the activities of lipid metabolizing enzymes serum lecithin cholesterol acyl transferase (LCAT) and hepatic triglyceride lipase (HTGL). The levels of liver tissue fatty acids (saturated, mono and polyunsaturated) such as palmitic acid, stearic acid, oleic acid, linoleic acid, arachidonic acid and linolenic acid monitored by gas chromatography were considerably altered in acetaminophen intoxicated animals when compared with control animals. The prior oral administration of Sargassum polycystum (200 mg/kg body wt./day for a period of 15 days) crude extract showed considerable prevention in the severe disturbances of lipid profile and metabolizing enzymes triggered by acetaminophen during hepatic injury. Liver histology also showed convincing supportive evidence regarding their protective nature against fatty changes induced during acetaminophen intoxication. Thus the present study indicates that the protective nature of Sargassum polycystum extract may be due to the presence of active compounds possessing antilipemic property against acetaminophen challenge. (Mol Cell Biochem 276: 89–96, 2005)     

Protective effects of ginkgo biloba against acetaminophen-induced toxicity in mice

Background: The analgesic acetaminophen (AAP) causes a potentially fatal, hepatic centrilobular necrosis when taken in overdose. It was reported that these toxic effects of AAP are due to oxidative reactions that take place during its metabolism. Objective: In this study, we aimed to investigate the possible beneficial effect of Ginkgo biloba (EGb), an antioxidant agent, against AAP toxicity in mice. Methods: Balb/c mice were injected i.p. with: (1) vehicle, control (C) group; (2) a single dose of 50 mg/kg Ginkgo biloba extract, EGb group; (3) a single dose of 900 mg/kg i.p. acetaminophen, AAP group, and (4) EGb, in a dose of 50 mg/kg after AAP injection, AAP + EGb group. Serum ALT, AST, and tumor necrosis factor-alpha (TNF-α) levels in blood and glutathione (GSH), malondialdehyde (MDA) levels, myeloperoxidase (MPO) activity, and collagen contents in liver tissues were measured. Formation of reactive oxygen species in hepatic tissue samples was monitored by using chemiluminescence (CL) technique with luminol and lusigenin probe. Tissues were also examined microscopically. Results: ALT, AST levels, and TNF-α were increased significantly (p < 0.001) after AAP treatment, and reduced with EGb. Acetaminophen caused a significant (p < 0.05–0.001) decrease in GSH levels while MDA levels and MPO activity were increased (p < 0.001) in liver tissues. These changes were reversed by EGb treatment. Furthermore, luminol and lusigenin CL levels in the AAP group increased dramatically compared to control and reduced by EGb treatment (p < 0.01). Conclusion: Our results implicate that AAP causes oxidative damage in hepatic tissues and Ginkgo biloba extract, by its antioxidant effects protects the tissues. Therefore, its therapeutic role as a “tissue injury-limiting agent” must be further elucidated in drug-induced oxidative damage.     

Protective effects of Rosmarinus tomentosus ethanol extract on thioacetamide-induced liver cirrhosis in rats

The capability of an ethanol extract of Rosmarinus tomentosus to protect rat liver in an experimental model of cirrhosis induced by thioacetamide (TAA) has been evaluated. Four groups of rats were used: Two of them received 300 mg TAA/l in the drinking water for 3 months while the other two, which served as controls, were given water ad libitum. During the same period and for each one of the treatments, one group received a semi-purified (SP) diet and the other one was fed the same diet supplemented with 1% of the dry residue obtained from R. tomentosus ethanol extract (SP+E). There was a significant reduction of TAA toxicity in rats fed the SP+E diet, as assessed by plasma and liver biochemical markers, and by liver histopathology. Plasma total protein concentration was restored, urea concentration and plasma alkaline phosphatase and gamma-glutamyl-transferase activities were reduced. A significant correction of plasma fatty acids concentrations was also evident. Hepatic alkaline phosphatase and gamma-glutamyl-transferase activities were significantly reduced in animals fed SP+E diet and glucose-6-phosphatase activity was significantly enhanced. The results suggest that R. tomentosus ethanol extract administered in the diet affords protection against TAA-induced cirrhosis, preventing most of the histological changes and functionality alterations own to this experimental pathology.     

Anti-herpes simplex virus effect of a seed extract from the tropical plant Licania tomentosa (Benth.) Fritsch (Chrysobalanaceae)

Incubation of acyclovir-resistant herpes simplex virus type 1 (ACVr-HSV1), during infection of the HEp-2 cell culture, with an extract prepared from the seeds of Licania tomentosa (Benth.) Fritsch (Chrysobalanaceae) species impaired the productive replication of this virus in a concentration-dependent manner. The extract was able to inhibit extracellular virus (virucidal effect) and also interfered with a very early event of cell infection, at a non-cytotoxic concentration.     

Protective effect of Dunaliella salina (Volvocales, Chlorophyta) against experimentally induced fibrosarcoma on wistar rats

The beta-carotene-yielding microalga, Dunaliella salina (Dunal) Teod. maintained in De Walne's medium was harvested and lyophilized. Fibrosarcoma was induced in rats by 20-methylcholanthrene. 0.5 g and 1.0 g of lyophilized D. salina powder was administered to the rats orally through carboxy methyl cellulose. Cisplatin was administered along with vitamin E to compare the protective effect of D. salina against fibrosarcoma. Administration of D. salina decreased the levels of cholesterol and lactate dehydrogenase as well as the activities of catalase, superoxide dismutase, serum aspartate aminotransaminase, serum alanine aminotransferase, when compared to control. A significant reduction in the levels of hepatic and renal RNA and DNA was observed in the sarcoma rats when treated with D. salina powder. Histopathological studies of tumor tissues showed regenerative and regressive changes. beta-carotene globules isolated from the powder of Dunaliella salina confirmed the presence of 9-cis-beta-carotene and all-trans-beta-carotene.     

Preliminary studies of Mammea americana L. (Guttiferae) bark/latex extract point to an effective antiulcer effect on gastric ulcer models in mice

Plant extracts are some of the most attractive sources of new drugs and have shown promising results for the treatment of gastric ulcers. Several folk medicinal plants and herbs have been used to treat gastrointestinal disorders, including gastric ulcers. Mammea americana L. (Guttiferae) fruit is very common in the diet of the population of northern South America. Our research interest in this plant arose because of its potential medicinal value as a tonic and against stomachache, as used in folk medicine. In this paper we evaluated three different extracts (ethanolic/EtOH, methanolic/MeOH and dichloromethane/DCM) obtained from M. americana L., for their ability to protect the gastric mucosa against injuries caused by necrotizing agents (0.3 M HCl/60% EtOH), hypothermic restraint stress, nonsteroidal anti-inflammatory drugs (NSAID, indomethacin) and pylorus ligation. In the HCl/EtOH-induced gastric-ulcer model, EtOH and DCM extracts demonstrated significant inhibition of the ulcerative lesion index by 54% (12.0 +/- 2.6 mm) and 86% (3.7 +/- 1.8 mm), respectively, in relation to the control value (26.0 +/- 1.4 mm) (p<0.0001). In the NSAID/cholinomimetic-induced lesion model, both EtOH and DCM extracts showed antiulcerogenic effects with significant reduction in the damage to these gastric lesions of 36% (8.3 +/- 2.0 mm) and 42% (7.5 +/- 1.4 mm), respectively, as compared to the control group (13.0 +/- 0.9 mm) (p<0.0001). In the gastric ulcer induced by hypothermic-restraint stress, both extracts also showed significant activity, and inhibited the gastric lesion index by 58% and 75%, respectively. The EtOH and DCM extracts also changed gastric juice parameters as well as those of cimetidine, decreased gastric acid secretion significantly (p<0.0001), increased pH values and promoted reduced acid output (p<0.0001). In all gastric-ulcer-induced models, MeOH extract did not show any significant antiulcerogenic activity, nor did it change gastric-juice parameters (p>0.05). The results suggest that EtOH and DCM extracts obtained from M. americana possess excellent antisecretory and/or gastrotective effect in all gastric ulcer models. These results suggest that the antiulcerogenic compound(s) present in M. americana may be clustered in the apolar fraction, which will be investigated by our group for the probable mechanisms of action.     

Seed germination and dormancy in the medicinal woodland herbs Collinsonia canadensis L. (Lamiaceae) and Dioscorea villosa L. (Dioscoreaceae)

We used a double germination phenology or “move-along” experiment (sensu Baskin and Baskin, 2003) to characterize seed dormancy in two medicinal woodland herbs, Collinsonia canadensis L. (Lamiaceae) and Dioscorea villosa L. (Dioscoreaceae). Imbibed seeds of both species were moved through the following two sequences of simulated thermoperiods: (a) 30/15 °C→20/10 °C→15/6 °C→5 °C→15/6 °C→20/10 °C→30/15 °C, and (b) 5 °C→15/6 °C→20/10 °C→30/15 °C→20/10 °C→15/6 °C→5 °C. In each sequence, seeds of both species germinated to high rates (>85%) at cool temperatures (15/6 and 20/10 °C) only if seeds were previously exposed to cold temperatures (5 °C). Seeds kept at four control thermoperiods (5, 15/6, 20/10, 30/15 °C) for 30 d showed little or no germination. Seeds of both species, therefore, have physiological dormancy that is broken by 12 weeks of cold (5 °C) stratification. Morphological studies indicated that embryos of C. canadensis have “investing” embryos at maturity (morphological dormancy absent), whereas embryos of D. villosa are undeveloped at maturity (morphological dormancy present). Because warm temperatures are required for embryo growth and cold stratification breaks physiological dormancy, D. villosa seeds have non-deep simple morphophysiological dormancy (MPD). Neither species afterripened in a 6-month dry storage treatment. Cold stratification treatments of 4 and 8 weeks alleviated dormancy in both species but C. canadensis seeds germinated at slower speeds and lower rates compared to seeds given 12 weeks of cold stratification. In their natural habitat, both species disperse seeds in mid- to late autumn and germinate in the spring after cold winter temperatures alleviate endogenous dormancy.     

Protective effects of a standard extract of Mangifera indica L. (VIMANG) against mouse ear edemas and its inhibition of eicosanoid production in J774 murine macrophages

A standard aqueous extract of Mangifera indica L., used in Cuba as antioxidant under the brand name VIMANG, was tested in vivo for its anti-inflammatory activity, using commonly accepted assays. The standard extract of M. indica, administered orally (50-200mg/kg body wt.), reduced ear edema induced by arachidonic acid (AA) and phorbol myristate acetate (PMA) in mice. In the PMA model, M. indica extract also reduced myeloperoxidase (MPO) activity. In vitro studies were performed using macrophage cell line J774 stimulated with pro-inflammatory stimuli lipopolysaccharide-interferon gamma (LPS-IFNgamma) or calcium ionophore A23187 to determine prostaglandin PGE(2) or leukotriene LTB(4) release, respectively. The extract inhibited the induction of PGE(2) and LTB(4) with IC(50) values of 21.7 and 26.0microg/ml, respectively. Mangiferin (a glucosylxanthone isolated from the extract) also inhibited these AA metabolites (PGE(2), IC(50) value=17.2microg/ml and LTB(4), IC(50) value=2.1microg/ml). These results represent an important contribution to the elucidation of the mechanism involved in the anti-inflammatory and anti-nociceptive effects reported for the standard extract of M. indica VIMANG.     

Study on the diuretic activity of Strychnos potatorum Linn. seed extract in albino rats

Methanol extract of Strychnos potatorum Linn. seeds (SPSE) was evaluated for its diuretic activity in Wistar albino rats. The SPSE was administered at the graded doses of 200, 400, and 600 mg/kg body weight. The parameters which were taken into account during the experimental on each rat were: total urine volume (corrected for water intake during the test period), body weight before and after the experiment, and the concentration of sodium, potassium, and chloride ions in urine. The total urine volumes of the SPSE (600 mg/kg)-treated rats were evaluated nearly two and half fold then compared with the control (saline treated) group. Excretion of cations (sodium and potassium ions) and anions (chloride ions) also increased significantly with respect to the control group. The diuretic effect was comparable with that of the standard drug Furosemide. The increase of cations in the urine on treatment with Strychnos potatorum seed extract (SPSE) was dose-dependent. This effect supports the use of the Strychnos potatorum seeds as a diuretic in folk remedies.     

火炭母的一个新异名及其系统位置初探

该文将铺地火炭母(Polygonum chinense L. var. procumbens Z. E. Zhao et J. R. Zhao)处理为火炭母原变种(Persicaria chinensis var. chinensis)的异名,并讨论了火炭母在命名上的问题,及其系统学位置。     

Taxonomic studies on three marine pleurostomatid ciliates, Litonotus bergeri nov. spec., L. blattereri nov. spec. and L. petzi nov. spec. (Ciliophora, Pleurostomatida) from North China Sea

The morphology and infraciliature of three pleurostomatid ciliates, Litonotus bergeri nov. spec., L. blattereri nov. spec. and L. petzi nov. spec., collected from mariculture ponds near Qingdao (Tsingtao), China, were investigated using live observations and the protargol impregnation method. These new species are distinguished from their congeners by a combination of characters including the typical distribution of extrusomes, i.e., along entire ventral margin, the number of macronuclear nodules, features and number of somatic kineties, living morphology, number and position of contractile vacuoles and their marine biotopes. Considering the distribution of extrusomes and general morphology, five new combinations are suggested, Litonotus vermiforme (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum vermiforme Sauerbrey, 1928], Litonotus levigatum (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum levigatum Sauerbrey, 1928], Litonotus undulatum (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum undulatum Sauerbrey, 1928], Loxophyllum pictus (Gruber, 1884) nov. comb. [basionym: Litonotus pictus Gruber, 1884] and Loxophyllum trichocystiferus (Foissner, 1984) nov. comb. [basionym: Litonotus trichocystiferus Foissner, 1984].     

Insecticidal effect of Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreaes) in combination with three diatomaceous earth formulations against Sitophilus granarius (L.) (Coleoptera: Curculionidae)

The insecticidal effect of the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreaes) in combination with three diatomaceous earth (DE) formulations against adults of the granary weevil, Sitophilus granarius (L.) (Coleoptera: Curculionidae) was tested in the laboratory. The three DEs were Insecto™, SilicoSec^® and PyriSec^®. The fungus was applied at 400 ppm alone, or in combination with 200 ppm of each of the three DEs. Mortality was measured after 7 d of exposure. Bioassays were conducted at three temperatures 20, 25 and 30 °C and two relative humidities (rh) 55% and 75%. On wheat treated with B. bassiana alone, mortality was higher at 55% than at 75% rh. Also, the fungus alone was less effective at 20 °C than at the other two temperatures tested, but mortality did not exceed 52% for any of the conditions tested. Similar mortality levels were also noted on wheat treated with each of the three DEs alone. The simultaneous presence of B. bassiana and DE increased weevil mortality. In this combination, mortality was higher at high temperatures and low rh, and this effect was similar for all DEs tested. Progeny production on wheat treated with B. bassiana was higher that the respective progeny counts in the DE-treated wheat. The results indicate that a combination of B. bassiana and DEs is effective against S. granarius, under a broad range of temperature and rh levels in stored wheat.     

大型海藻龙须菜抽提液对褶皱臂尾轮虫生命表参数的影响

大型海藻富含多种活性物质,具有抗衰老等生物活性;轮虫是良好的潜在抗衰老研究模式生物。本研究以褶皱臂尾轮虫(Brachionus plicatilis)作为实验对象,研究了不同浓度的大型海藻龙须菜抽提液(0,250,500,750,1000 mg/L)和不同浓度的食物(蛋白核小球藻和普通小球藻)对褶皱臂尾轮虫生命表参数的影响。结果表明:与对照组相比,食物浓度为1.0×10~6个/mL蛋白核小球藻时,不同浓度龙须菜抽提液对轮虫产卵数、平均寿命、净生长率以及世代时间有显著促进效应(P0.05);轮虫平均产卵数及寿命在龙须菜抽提液浓度750 mg/L处达到最高,分别为16只和13.9d(P0.05)。食物浓度为2.0×10~6个/mL普通小球藻时,轮虫平均产卵数和寿命在抽提液浓度为500 mg/L处达到最高,分别为16只和13.6d(P0.05),轮虫平均寿命和净生长率均有显著提高(P0.05)。相同龙须菜抽提液浓度下,食物浓度为1.0×10~6个/mL蛋白核小球藻下轮虫的净生长率、世代时间均显著高于食物浓度为2.0×10~6个/mL蛋白核小球藻培养的轮虫(P0.05);食物浓度为2.0×10~6个/mL时,普通小球藻培养轮虫的净生长率和世代时间均显著高于蛋白核小球藻实验组(P0.05)。交互作用分析显示,龙须菜抽提液与小球藻的交互作用对褶皱臂尾轮虫的内禀增长率有显著影响(P0.05)。研究结果表明,大型海藻龙须菜抽提液对褶皱臂尾轮虫的生长与生殖有促进作用,延长轮虫寿命。     

Protective effect of Piper betle leaf extract against cadmium-induced oxidative stress and hepatic dysfunction in rats

The present study was undertaken to examine the attenuative effect of Piper betle leaf extract (PBE) against cadmium (Cd) induced oxidative hepatic dysfunction in the liver of rats. Pre-oral supplementation of PBE (200 mg/kg BW) treated rats showed the protective efficacy against Cd induced hepatic oxidative stress. Oral administration of Cd (5 mg/kg BW) for four weeks to rats significantly (P > 0.05) elevated the level of serum hepatic markers such as serum aspartate transaminase (AST), serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), gamma-glutamyl transpeptidase (GGT), bilirubin (TBRNs), oxidative stress markers viz., thiobarbituric acid reactive substances (TBARS), lipid hydroperoxides (LOOH), protein carbonyls (PC) and conjugated dienes (CD) and significantly (P > 0.05) reduced the enzymatic antioxidants viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) and non-enzymatic antioxidants Viz., reduced glutathione (GSH), total sulfhydryls (TSH), vitamin C and vitamin E in the liver. Pre-oral supplementation of PBE (200 mg/kg BW) in Cd intoxicated rats, the altered biochemical indices and pathological changes were recovered significantly (P > 0.05) which showed ameliorative effect of PBE against Cd induced hepatic oxidative stress. From the above findings, we suggested that the pre-administration of P. betle leaf extract exhibited remarkable protective effects against cadmium-induced oxidative hepatic injury in rats.     

Study of pollen brush in selected species of Astragalus L. subgenus Pogonophace Bunge (Leguminosae)

Nine species of Lippia (Verbenaceae) were studied by RAPD markers in order to evaluate the degree of genetic diversity. The following species were collected at the Cadeia do Espinhaço Mountains, Southeast Brazil: L. corymbosa, L. diamantinensis, L. filifolia, L. florida, L. hermannioides, L. lupulina, L. rotundifolia, L. rosella and L. sidoides. The analysis was performed using 18 primers that generated 490 fragments and only one primer was found to be monomorphic in all individuals. The average interspecific genetic distances were similar for all species and higher than the intraspecific genetic distances. Species with narrow occurrence did not show low intraspecific diversity. The molecular data were used to generate an UPGMA dendrogram that showed two major groups with a clear distribution among the species. RAPD analysis was efficient to address the genetic diversity of Lippia species and contributed to understand the adaptation to the environment, conservation and taxonomic implications.     

Protective effects of Danshensu from the aqueous extract of Salvia miltiorrhiza (Danshen) against homocysteine-induced endothelial dysfunction

Homocysteine (Hcy) is a by-product of methionine metabolism. An imbalance of Hcy in the body may lead to hyperhomocysteinemia, a condition with elevated Hcy concentration in blood that may be one of the risk factors responsible for the development of several vascular diseases (thromboembolism, atherosclerosis, stroke, vascular diseases and dementia). Radix Salvia miltiorrhiza (Danshen), a well-known Chinese medicinal herb that can activate and improve blood microcirculation, is noticeable for its beneficial effect in treating cardiovascular diseases. The present study is to demonstrate the protective effect of Danshen extract against the homocysteine-induced adverse effect on human umbilical vein endothelial cell (HUVEC). Homocysteine (5 mM) not only decreased the cell viability but also caused the disruption of capillary-like structure formation in vitro. The protective effect of Danshen aqueous extract and its active compounds on endothelial cell function were demonstrated through an in vitro tube formation assay, which mimics the new blood vessel formation. To identify the active components in the aqueous extract of Danshen, the content was characterized by instrumental analysis using high performance liquid chromatography with diode array detector (DAD) and electrospray tandem mass spectrometry (ESI-MS/MS). Interestingly, Danshen extract and its pure compounds showed different effectiveness in protecting HUVEC against Hcy-induced injury according to the following descending order: Danshen aqueous extract, 3-(3,4-dihydroxy-phenyl)-2-hydroxy-propionic acid (Danshensu), protocatechuic acid, catechin and protocatechualdehyde. We believed that such findings might provide evidence in understanding the beneficial effects of Danshen on the cardiovascular system.     

A mitochondrial DNA based phylogeny of weakfish species of the Cynoscion group (Pisces: Sciaenidae)

We infer the phylogeny of fishes in the New World Cynoscion group (Cynoscion, Isopisthus, Macrodon, Atractoscion, Plagioscion) using 1603 bp of DNA sequence data from three mitochondrial genes. With the exception of Plagioscion, whose position was ambiguous, the Cynoscion group is monophyletic. However, several genera examined are not monophyletic. Atlantic and Pacific species of Cynoscion are interspersed in the tree and geminate species pairs are identified. Intergeneric relationships in the group are clarified. Our analysis is the first comprehensive phylogeny for the Cynoscion group based on molecular data and provides a baseline for future comparative studies of this important group.