In vitro and in vivo antiplasmodial activity of the root extracts of Brucea mollis Wall. ex Kurz

Malaria control is compromised worldwide by continuously evolving drug-resistant strains of the parasite demanding exploration of natural resources for developing newer antimalarials. The northeastern region of India is endemic for malaria characterized by high prevalence of drug-resistant Plasmodium falciparum strains. Many plants are used by the indigenous communities living in the northeast India in their traditional system of medicine for the treatment of malarial fever. Folklore claim of antimalarial property of one such plant Brucea mollis was evaluated in vitro and in vivo for antiplasmodial activity. Crude extracts from dried B. mollis root powder were prepared through soxhlet extraction using petroleum ether, methanol, and water sequentially. Methanol extract was further partitioned between chloroform and water. These extracts were tested in vitro against laboratory-adapted chloroquine-sensitive and chloroquine-resistant strains of P. falciparum. In in vitro evaluation, extracts were found more active on the chloroquine-sensitive strain. Methanolic-chloroform (IC₅₀ 5.1 μg?ml^?1) and methanolic-aqueous (IC₅₀ 13.9 μg?ml^?1) extracts recorded significant in vitro antiplasmodial activity which was also supported by their promising in vivo activity (ED₅₀ 72 and 30 mg?kg^?1?bw?day^?1, respectively) against chloroquine-resistant Plasmodium yoelli N-67 strain in Swiss albino mice. Methanolic-aqueous extract-treated mice survived on average for 14 days that was comparable to the reference drug chloroquine. This is the first report of antiplasmodial activity of B. mollis validating the traditional use of this plant as antimalarial in the northeast India and calls for further detailed investigations.     

In vitro antiplasmodial and phytochemical study of five Artemisia species from Iran and in vivo activity of two species

The extract from Artemisia annua, containing artemisinin, has been proven active against multidrug resistant Plasmodium falciparum in previous studies. The purpose of this paper was to study five Artemisia species from Iran for their in vitro and in vivo antimalarial property and detection of artemisinin in the active species by chromatographic and spectroscopic methods including nuclear magnetic resonance (NMR) spectroscopy. Dried plants were extracted by 80% ethanol, and total extracts were investigated for antiplasmodial property and artemisinin content by TLC, HPLC, and ¹H-NMR techniques. Two plants (A. annua L. and Artemisia absinthium L.) showed good antiplasmodial activity against multidrug resistant and sensitive strain of P. falciparum. A. absinthium and A. annua at concentrations of 200 mg/kg for 4 days reduced parasitemia in BALB/C mice infected with Plasmodium bergei by 94.28% and 83.28%, respectively, but we could not detect artemisinin in all plants studied in this research. The antiplasmodial property of these two herbs is possibly related to essential oils that present in high amounts in their extracts.     

In vitro antiplasmodial activity of some medicinal plants of Burkina Faso

Malaria remains a major public health problem due to the emergence and spread of Plasmodium falciparum drug resistance. There is an urgent need to investigate new sources of antimalarial drugs which are more effective against Plasmodium falciparum. One of the potential sources of antimalarial drugs is traditional medicinal plants. In this work, we studied the in vitro antiplasmodial activity of chloromethylenic, methanolic, and MeOH/H₂O (1/1) crude extracts and decoction obtained from eight medicinal plants collected in Burkina Faso and of total alkaloids for five plants. Extracts were evaluated in vitro for efficacy against Plasmodium falciparum strain K1, which is resistant to chloroquine, pyrimethamine and proguanil using the fluorescence-based SYBR Green I assay. The antiproliferative activity on human-derived hepatoma cell line HepG2 and Chinese hamster ovary (CHO) cells was evaluated using the 3-[4,5-dimethylthyazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test in order to determine the selectivity index. Among the plant extracts tested for in vitro antiplasmodial activity, 16 were considered to be inactive (with IC₅₀?>?10 μg/ml), six showed a moderate activity (5?<?IC₅₀?≤?10 μg/ml), and six were found to have a good in vitro activity with IC₅₀ value?≤?5 μg/ml. The highest antiplasmodial activity was found for extracts from: the alkaloid leaf extract and the chloromethylenic extracts of Combretum fragrans (IC₅₀?=?3 μg/ml, IC₅₀?=?5 μg/ml), the total alkaloids and the chloromethylenic leaf extracts of Combretum collinum (IC₅₀?=?4 μg/ml), the MeOH/H₂O leaf extract of Terminalia avicennioides (IC₅₀?=?3.5 μg/ml), and the alkaloid leaf extract of Pavetta crassipes (IC₅₀?=?5 μg/ml). Three other extracts showed moderate antiplasmodial activity (5?<?IC₅₀?≤?10 μg/ml): Terminalia avicennioides and Combretum fragrans methanolic extracts and Acacia kirkii alkaloid leaf extract (IC₅₀?=?6.5, 9 and 10 μg/ml respectively). The Terminalia avicennioides crude MeOH/H₂O (80:20 v/v) extract of the leaves was submitted to a successive liquid/liquid extraction with ethylacetate and n-butanol respectively. The extracts were investigated for in vitro antiplasmodial activity and antioxidant properties using DPPH^●, ABTS⁺ and FRAP methods. The ethylacetate extract showed the best antiplasmodial activity (7 μg/ml) and the active constituent was isolated as ellagic acid by bioguided fractionation with an IC₅₀?=?0.2 μM on Plasmodium falciparum and SI?=?152. Besides, Terminalia avicennioides leaf extract and ellagic acid showed a good antioxidant activity. Our finding confirms the importance of investigating the antimalarial activity of plant species used in traditional medicine. Overall, two plants belonging to the Combretaceae family, Combretum fragrans and Combretum collinum appeared to be the best candidates and will be further investigated for their antiplasmodial properties, in order to isolate the molecules responsible for the antiplasmodial activity.     

The in vitro and in vivo activity of ciprofloxacin

The antibacterial activity of ciprofloxacin (Bay o 9867) was compared with those of norfloxacin, nalidixic acid, trimethoprim-sulfamethoxazole, cefaclor, sisomicin and cefotaxime in in vitro and mouse protection studies. Approximately 300 clinical isolates of clinically important gram-positive and gram-negative species were used. The median MICs of ciprofloxacin against gram-positive and gram-negative bacteria ranged from ≤0.015–1 mg/l. Ciprofloxacin was 2–8 fold more active than norfloxacin and 100-fold more active than nalidixic acid. It also had a wider spectrum of activity against gram-positive organisms including even enterococci. No cross-resistance was observed between ciprofloxacin andβ-lactam antibiotics or aminoglycosides. Only acidic pH conditions decreased its activity. Ciprofloxacin showed rapid bactericidal action against organisms in both the logarithmic and stationary growth phases. In mouse protection studies (intraperitoneal infection) ciprofloxacin was significantly more effective than norfloxacin, ampicillin, trimethoprim-sulfamethoxazole, and also showed excellent activity againstPseudomonas infections.     

Beta amyloid angiogenic activity in vitro and in vivo

Angiogenesis has been suggested as a direct contributor to Alzheimer's disease (AD) pathology. The major pathological hallmarks of AD are the presence of neurofibrillary tangles and, beta-amyloid plaques associated with activated microglia, astrocytes, degenerating neurons and vascular toxicity. In this study, Abeta1-40 and Abeta1-42 peptides, both components of the senile plaques in AD, were used to study their angiogenic activity in vitro, by using normal human cerebral endothelial cells (HCECs), and in vivo, by using the chick embryo chorioallantoic membrane (CAM) assay. Results showed that both peptides stimulate in vitro endothelial cell proliferation, chemotaxis and morphogenesis in Matrigel. Moreover, by using the aorta ring assay, both peptides stimulated the formation of capillary-like structures. An angiogenic response was induced in the CAM assay, similar to that induced by fibroblast growth factor-2 (FGF-2), a well-known angiogenic cytokine. Overall, these data support the hypothesis that Abeta peptides may contribute to angiogenesis occurring in AD and suggest that limiting the pro-angiogenic activity of Abeta peptides may therefore provide a useful target to control angiogenesis associated to AD and therefore limit the disease progression.     

In vitro and in vivo antioxidant activity of ambroxol

Abstract In addition to a mucolytic action, ambroxol has antioxidant and anti-inflammatory properties. The antioxidant effects of ambroxol were studied both in vitro and in vivo. In vitro methods, such as (1) inhibition of hyaluronic acid degradation induced by hydroxy radicals and (2) standard lipid peroxidation assay in rat liver mitochondria and gastric mucosa, induced by tert-butyl hydroperoxide, were used. The in vivo approach was based on the study of the protective effect of pretreatment with ambroxol in a rat model of gastric corpus and antral lesions, induced by indomethacin. The inhibition of the degradation of hyaluronic acid was measured as a change of its viscosity; ambroxol (1,000 µl/l) reduced the degradation by 93%. Lipid peroxidation with tert-butyl hydroperoxide as a source of radicals was followed by the formation of thiobarbituric acid reactive substances. Ambroxol (10 mmol/l) inhibited lipid peroxidation by 96% in the rat liver mitochondria, and by 74% in the gastric mucosa. In vivo, ambroxol was administered p.o. at a dose of 10, 30, and 50 mg/kg, at 5, 30, and 60 min prior to indomethacin administration. The highest inhibition of the number of corpus gastric lesions and lowering of the lesion index (38% and 62%, respectively) was shown after the administration of 50 mg/kg, 30 min before indomethacin administration. Antral lesions were inhibited to a lesser extent by the same dose of ambroxol, administered 30 min before indomethacin treatment. Inhibition of the number of antral lesions reached 27% and the total area of the gastric damage was even larger (the ulcer index reached -5%).     

Immunostimulant activity of n-butanol fraction of root bark of Oroxylum indicum, vent

In the present study, the immunomodulatory activity and the mechanism of action of the n-butanol fraction (100 mg/kg body weight, per os, once daily for 22 consecutive days) of the root bark of Oroxylum indicum, vent. (Bignoniaceae) was evaluated in rats using measures of immune responses to sheep red blood cells (SRBC haemagglutinating antibody [HA] titer) and delayed-type hypersensitivity (DTH) reactions. In response to SRBC, treatment with the n-butanol fraction caused a significant rise in circulating HA titers during secondary antibody responses, indicating a potentiation of certain aspects of the humoral response. The treatment also resulted in a significant rise in paw edema formation, indicating increased host DTH response. Additionally, the antioxidant potential of the drug was exhibited by significant reductions in whole blood malondialdehyde (MDA) content along with a rise in the activities/levels of superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH). Furthermore, histopathologic analysis of lymphoid tissues showed an increase in cellularity, e.g., T-lymphocytes and sinusoids, in the treatment group. In contrast, dexamethasone treatment caused significant reduction in the HA titer, DTH responses, and antioxidant potential. In a triple antigen-mediated immunological edema model, the extent of edema raised in drug-treated rats was greater compared to that in control rats, thus confirming enhanced DTH reactions in response to the drug treatment. Based on the above findings, the reported immunomodulatory activity of an active fraction of O. indicum might be attributed to its ability to enhance specific immune responses (both humoral and cell-mediated) as well as its antioxidant potential.     

In vitro and in vivo antioxidant activity of ambroxol

In addition to a mucolytic action, ambroxol has antioxidant and anti-inflammatory properties. The antioxidant effects of ambroxol were studied both in vitro and in vivo. In vitro methods, such as (1) inhibition of hyaluronic acid degradation induced by hydroxy radicals and (2) standard lipid peroxidation assay in rat liver mitochondria and gastric mucosa, induced by tert-butyl hydroperoxide, were used. The in vivo approach was based on the study of the protective effect of pretreatment with ambroxol in a rat model of gastric corpus and antral lesions, induced by indomethacin. The inhibition of the degradation of hyaluronic acid was measured as a change of its viscosity; ambroxol (1,000 microl/l) reduced the degradation by 93%. Lipid peroxidation with tert-butyl hydroperoxide as a source of radicals was followed by the formation of thiobarbituric acid reactive substances. Ambroxol (10 mmol/l) inhibited lipid peroxidation by 96% in the rat liver mitochondria, and by 74% in the gastric mucosa. In vivo, ambroxol was administered p.o. at a dose of 10, 30, and 50 mg/kg, at 5, 30, and 60 min prior to indomethacin administration. The highest inhibition of the number of corpus gastric lesions and lowering of the lesion index (38% and 62%, respectively) was shown after the administration of 50 mg/kg, 30 min before indomethacin administration. Antral lesions were inhibited to a lesser extent by the same dose of ambroxol, administered 30 min before indomethacin treatment. Inhibition of the number of antral lesions reached 27% and the total area of the gastric damage was even larger (the ulcer index reached -5%).     

In vitro and in vivo anti-allergic activity of soy sauce

Soy sauce (Shoyu) is a traditional fermented seasoning of Japan and available throughout the world. Polysaccharides were obtained from dialysate of Shoyu, and these Shoyu polysaccharides (SPS) were examined for anti-allergic activity in vitro and in vivo. The SPS originated from partially-degraded polysaccharides of soybeans by mold enzymatic hydrolyses, and Shoyu contained about 1% (w/v) SPS. First, the inhibitory effects of SPS on hyaluronidase, which is known to be related to inflammation and allergic responses, were as potent as those of an anti-allergic medicine, disodium cromoglycate. Second, SPS significantly inhibited the release of histamine from rat basophilic leukemia (RBL-2H3) cells, which had been induced by the antigen. Third, orally administered SPS had a significant suppressive effect on passive cutaneous anaphylaxis induced in the ears of mice. These results suggest that SPS may have anti-allergic activities, and soy sauce is a potentially promising seasoning for the treatment of allergic diseases through food.     

注射用头孢拉宗钠的体内外抗菌活性研究

目的评价注射用头孢拉宗钠的体内外抗菌活性。方法选取663株临床分离致病菌为实验菌,以头孢美唑、头孢西丁、头孢替坦、头孢米诺、头孢唑啉、头孢呋辛、头孢哌酮、头孢吡肟为对照药物,分别采用平皿二倍稀释法测定药物最低抑菌浓度（MIC）、最低杀菌浓度（MBC）、绘制杀菌曲线（KCs）并行诱导耐药实验,观察头孢拉宗的体外抗菌作用;建立小鼠腹腔感染模型,评价头孢拉宗皮下给药对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌感染小鼠的体内疗效。结果头孢拉宗对多种革兰阴性菌具有较高的抗菌活性,尤以对大肠埃希菌和肺炎克雷伯杆菌的抗菌活性更为突出,其MIC50、MIC90分别为0.5、8μg/ml,对产超广谱β-内酰胺酶大肠埃希菌和肺炎克雷伯杆菌的抗菌活性也较强,其MIC50、MIC90分别为4、8μg/ml;头孢拉宗对革兰阴性菌的抗菌作用大多优于头孢西丁、头孢美唑、头孢唑啉、头孢哌酮、头孢替坦和头孢呋辛,而对革兰阳性菌的抗菌活性较弱,与头孢替坦和头孢米诺相近。MBC和KCs测定结果表明,头孢拉宗对金黄色葡萄球菌、大肠埃希菌、肺炎克雷伯杆菌均具有杀菌作用。以1/4MIC剂量诱导20d后,头孢拉宗对金黄色葡萄球菌、大肠埃希菌和肺炎克雷伯杆菌的抗菌活性无明显改变。头孢拉宗皮下给药对大肠埃希菌ATCC25922、大肠埃希菌1515、肺炎克雷伯杆菌7、肺炎克雷伯杆菌9613感染小鼠的体内疗效明显优于头孢美唑和头孢唑啉（均P〈0.01）;对金黄色葡萄球菌感染小鼠的体内疗效与头孢美唑相近（P〉0.05）,但弱于头孢唑啉（P〈0.01）。结论注射用头孢拉宗钠对多数革兰阴性菌,特别是大肠埃希菌和肺炎克雷伯杆菌具有较强的体外抗菌活性;同时对大肠埃希菌、肺炎克雷伯杆菌、金黄色葡萄球菌腹腔感染小鼠的体内疗效也较好。     

Purification of Ascaris suum antigen: its allergenic activity in vitro and in vivo

Crude aqueous extracts of Ascaris suum (CE) have been used widely to study IgE-mediated reactions in various experimental preparations. Because some CE may contain a polypeptide, a mast cell degranulating peptide (MCDP), that degranulates mast cells by nonimmunologic mechanisms, various protocols have been used to ensure that the Ascaris preparation used did not contain MCPD. In general, these protocols have assumed MCDP had been without providing proof. Even protocols designed to isolate the major antigenic determinants from CE have usually been designed to evaluate immunogenic characteristics of the purified Ascaris; thus, few systematic comparisons of CE with purified Ascaris exist concerning mast cell degranulation, and few studies have demonstrated that MCDP has been removed during purification. Since Ascaris has proved to be useful in a variety of studies of IgE-mediated reactions, particularly in large animals (dog and sheep), we have developed a protocol to purify CE and MCDP and characterize their physiochemical and immunologic properties. We compared the allergenic activity of our purified Ascaris to that of CE and MCDP in skin and lung of natively sensitized dogs and in unsensitized rat peritoneal mast cells. Our results indicate that MCDP probably contaminates CE by less than 1.0%. However, the biologic activity of MCDP in dog lung appears insignificant and probably contributes little to CE-induced reactions in doses of CE commonly used (less than or equal to 100 mg injected). If a purified Ascaris preparation is essential, our protocol will yield an Ascaris preparation that has potent IgE-mediated effects in dog preparations with insignificant contamination by MCDP.     

Hexokinase activity in mouse embryos developed in vivo and in vitro

Micro-determination methods were used for quantitative examinationof possible differences in energy metabolism in mouse embryosarising after spontaneous ovulation or after gonadotrophin stimulation.Comparisons of embryonic development in vivo and in vitro werealso made. The relevance of the results to human developmentand their clinical significance are discussed. The enzymaticactivity of hexokinase, phosphofructokinase, glucose 6-phosphatedehydrogenase, malate dehydrogenase and lactate dehydrogenasein individual mouse embryos throughout preimplantation developmentwas evaluated. Hexokinase activity in 1-cell embryos was thelowest by far of the five enzymes measured, and the 0.035 ±0.010 pmol of nicotinamide adenine dinucleotide phosphate hydrogenaseformed/embryo/min was also lower than in any of the somaticorgans examined. Hexokinase activity, unlike the other enzymes,progressively increased in the morulae and blastocyst stagesin embryos obtained either by spontaneous ovulation or via gonadotrophinstimulation. Although there is a significant delay, this increasewas also observed when 2-cell embryos developed in vitro. Increasesin hexikinase activity were observed 68–75 h after humanchorionic gonadotrophin administration in vivo, but after 80–86h in vitro. These increases in vitro were inhibited by the administrationof actinomycin D added to the medium. The results suggest thathexokinase may be a key enzyme synthesized as the zygotic genomeis expressed in preimplantation embryos, and its measurementmay help to assess the quality of embryos developed in vitro.     

Fluorescent viral nanoparticles with stable in vitro and in vivo activity

We synthesized fluorescent capsid nanoparticles (FCNPs) by genetically inserting fluorescent protein (FP) (DsRed or eGFP) into each of 240 surface spike tips of hepatitis B virus (HBV) capsid particles. That is, when expressed in E. coli, FCNPs formed spherical nanoparticles with uniform diameter of about 40 nm owing to the self-assembly function of HBV core protein (i.e. basic assembly unit of capsid) and were successfully purified through Ni(+2) affinity- and sucrose gradient based purification. We also added the glycine-rich fexible linker peptides in between DsRed (or eGFP) and capsid to reduce fluorescence quenching among the densely displayed DsReds (or eGFPs) on the capsid surface. As compared to cognate fluorescent monomer proteins, it is notable that FCNPs showed a significantly amplified (160-170-fold) fluorescence intensity and enhanced conformational stability even in 50% serum solutin at 37 °C. The high conformational stability of FCNPs seems to result both from the highly stable structure of HBV capsid particles and from the well oriented insertion of fluorescent protein into capsid spike tip to keep native conformation of DsRed or eGFP. When estimated with continuous exposure to strong excitation light, FCNPs also showed much higher photostability than DsRed, eGFP, and a commonly used organic fluorescent dye, which happened presumably because the enhanced conformational stability of FCNPs significantly reduced photobleaching of fluorophores. Especially, it is notable that rFCNPs stably emitted high-level fluorescence inside mouse for a prolonged period, thereby showing high in vivo stability. The developed FCNPs are likely to have a great potential to be used as an effective and non-cytotoxic tool for in vivo optical imaging as well as in vitro fluorescent reporter in various biomolecular detection assays.     

In vitro antiplasmodial activity of bacterium RJAUTHB 14 associated with marine sponge Haliclona Grant against Plasmodium falciparum

Malaria is the most important parasitic disease, leading to annual death of about one million people, and the Plasmodium falciparum develops resistance to well-established antimalarial drugs. The newest antiplasmodial drug from a marine microorganism helps in addressing this problem. In the present study, Haliclona Grant were collected and subjected for enumeration and isolation of associated bacteria. The count of bacterial isolates was maximum in November 2007 (18?×?10(4) colony-forming units (CFU)?g(-1), and the average count was maximum during the monsoon season (117?×?10(3) CFU g(-1)). Thirty-three morphologically different bacterial isolates were isolated from Haliclona Grant, and the extracellular ethyl acetate extracts were screened for antiplasmodial activity against P. falciparum. The antiplasmodial activity of bacterium RJAUTHB 14 (11.98 μg[Symbol: see text]ml(-1)) is highly comparable with the positive control chloroquine (IC(50) 19.59 μg[Symbol: see text]ml(-1)), but the other 21 bacterial extracts showed an IC(50) value of more than 100 μg[Symbol: see text]ml(-1). Statistical analysis reveals that significant in vitro antiplasmodial activity (P?相似文献   

Immunomodulating activity of RU 41740: in vitro and in vivo studies on human lymphocytes

A group of institutionalized elderly subjects, selected on the basis of their skin hypoergy and displaying different kinds of T and B lymphocyte impairments has been chosen as a model to verify the in vivo immunopotentiating activity of RU 41740 on human lymphocytes. Oral treatment with the drug was able to: restore or improve the cutaneous delayed hypersensitivity to recall antigens; significantly increase the blastigenetic response to mitogenic and submitogenic doses of PHA and PWM and improve the in vitro PWM-induced synthesis of IgG and IgM. The immunopharmacological activity of RU 41740 appeared to persist three months after the end of therapy, without any direct stimulating activity on the peripheral blood lymphocytes. The in vitro results seem to suggest that peripheral lymphocytes are not directly influenced by the drug.     

Lysophosphatidic acid enhances antimycobacterial activity both in vitro and ex vivo

Lysophosphatidic acid (LPA) is a polar lipid metabolite which is involved in a wide range of biological processes, including cell proliferation and migration, wound healing, and increase of endothelial permeability. The present study reports evidences showing that LPA is able to enhance the antimicrobial activity of human macrophages and of bronchoalveolar lavage cells from tuberculosis patients leading to intracellular growth control of Mycobacterium tuberculosis. Such antimicrobial activity is mediated by the activation of phospholipase D which in turn induces acidification of M. tuberculosis containing phagosomes and is associated with the enhanced expression of Cathepsin D. These results suggest the possible protective role of this lysophospholipid in the activation of innate antimycobacterial response.