Inhibition of allergen-induced eosinophil recruitment by natural tetranortriterpenoids is mediated by the suppression of IL-5, CCL11/eotaxin and NFkappaB activation

Therapeutic effects of andiroba (Carapa guianensis Aubl) oil, compared to low power laser, on oral mucositis in children underwent chemotherapy: A clinical study

ETHNO-PHARMACOLOGICAL RELEVANCE

The Carapa guianensis Aubl, popularly known as andiroba, is a large tree of the Meliaceae family, commonly found in the Amazon region. The oil extracted from its seeds is recognized in traditional medicine and has high anti-inflammatory and analgesic potential, which are the basic prerequisites for a therapeutic agent that can be used in the treatment of oral mucositis (OM). Moreover, the aforementioned oil has antimicrobial, antiallergic, and parasiticidal actions and is effective in the management of cutaneous and muscular dysfunctions.

AIM OF THE STUDY

To evaluate the therapeutic effects of andiroba gel (Carapa guianensis Aubl) on the symptomatology and evolution of OM in children with leukemia who underwent chemotherapy and to compare it to the effects of low power laser.

MATERIALS AND METHODS

This randomized, double-blind clinical trial involved 60 patients of both genders with leukemia, with age ranging from six to twelve years. The patients were divided into two study groups: the andiroba group (n = 30) and the laser group (n = 30). The level of pain experienced by the patients was assessed using the Wong-Baker visual analog scale and the degree of severity of OM was assessed using a table, recommended by the World Health Organization, that depicts the degrees of severity of OM. The data obtained were analyzed using the Mann-Whitney test, with statistical significance indicated by a P value less than or equal to 0.05.

RESULTS

A statistically significant reduction in the degree of OM was observed on the fourth, fifth, and sixth days and in the pain scores on the second, third, and fourth days in the andiroba group after the manifestation of OM, compared to the laser group.

CONCLUSIONS

The use of andiroba oil effectively reduced the severity of OM and relieved pain, which resulted in a decrease in the severity of signs and symptoms in the patients in the andiroba group, compared to the laser group.

Ultrasound-assisted lipid extractions, enriched with sterols and tetranortriterpenoids, from Carapa guianensis seeds and the application of lipidomics using GC/MS

This study describes the optimized stages of lipid extraction assisted by ultrasound to increase the concentrations of limonoids and steroids from andiroba seeds, identified as Carapa guianensis Aublet, and the lipidome analyzed by TLC and GC/MS.

Biological Activities of Gedunin-A Limonoid from the Meliaceae Family

Gedunin is an important limonoid present in several genera of the Meliaceae family, mainly in seeds. Several biological activities have been attributed to gedunin, including antibacterial, insecticidal, antimalarial, antiallergic, anti-inflammatory, anticancer, and neuroprotective effects. The discovery of gedunin as a heat shock protein (Hsp) inhibitor represented a very important landmark for its application as a biological therapeutic agent. The current study is a critical literature review based on the several biological activities so far described for gedunin, its therapeutic effect on some human diseases, and future directions of research for this natural compound.

Natural heat shock protein 90 inhibitors in cancer and inflammation

Heat shock protein (HSP)90 is the most abundant HSPs, which are chaperone molecules whose major roles are cell protection and maintenance by means of aiding the folding, the stabilization and the remodeling of a wide range of proteins. A few hundreds of proteins depend on HSP90 chaperone activity, including kinases and transcriptional factors that play essential roles in cancer and inflammation, so that HSP90-targeted therapies have been considered as a potential strategy for the treatment of cancer and inflammatory-associated diseases. HSP90 inhibition by natural, semi-synthetic and synthetic compounds have yield promising results in pre-clinical studies and clinical trials for different types of cancers and inflammation. Natural products are a huge source of biologically active compounds widely used in drug development due to the great diversity of their metabolites which are capable to modulate several protein functions. HSP90 inhibitors have been isolated from bacteria, fungi and vegetal species. These natural compounds have a noteworthy ability to modulate HSP90 activity as well as serve as scaffolds for the development of novel synthetic or semi-synthetic inhibitors. Over a hundred clinical trials have evaluated the effect of HSP90 inhibitors as adjuvant treatment against different types of tumors and, currently, new studies are being developed to gain sight on novel promising and more effective approaches for cancer treatment. In this review, we present the naturally occurring HSP90 inhibitors and analogues, discussing their anti-cancer and anti-inflammatory effects.

Zinc Oxide Nanowires Exposure Induces a Distinct Inflammatory Response via CCL11-Mediated Eosinophil Recruitment

High aspect ratio zinc oxide nanowires (ZnONWs) have become one of the most important products in nanotechnology. The wide range applications of ZnONWs have heightened the need for evaluating the risks and biological consequences to these particles. In this study, we investigated inflammatory pathways activated by ZnONWs in cultured cells as well as the consequences of systemic exposure in mouse models. Confocal microscopy showed rapid phagocytic uptake of FITC-ZnONWs by macrophages. Exposure of macrophages or lung epithelial cells to ZnONWs induced the production of CCL2 and CCL11. Moreover, ZnONWs exposure induced both IL-6 and TNF-α production only in macrophages but not in LKR13 cells. Intratracheal instillation of ZnONWs in C57BL/6 mice induced a significant increase in the total numbers of immune cells in the broncho alveolar lavage fluid (BALFs) 2 days after instillation. Macrophages and eosinophils were the predominant cellular infiltrates of ZnONWs exposed mouse lungs. Similar cellular infiltrates were also observed in a mouse air-pouch model. Pro-inflammatory cytokines IL-6 and TNF-α as well as chemokines CCL11, and CCL2 were increased both in BALFs and air-pouch lavage fluids. These results suggest that exposure to ZnONWs may induce distinct inflammatory responses through phagocytic uptake and formation of soluble Zn²⁺ ions.

A Limonoid, 7-Deacetoxy-7-Oxogedunin (CG-1) from Andiroba (Carapa guianensis, Meliaceae) Lowers the Accumulation of Intracellular Lipids in Adipocytes via Suppression of IRS-1/Akt-Mediated Glucose Uptake and a Decrease in GLUT4 Expression

Limonoids are phytochemicals with a variety of biological properties. In the present study, we elucidated the molecular mechanism of suppression of adipogenesis in adipocytes by a limonoid, 7-deacetoxy-7-oxogedunin (CG-1) from Carapa guianensis (Meliaceae), known as andiroba. CG-1 reduced the accumulation of intracellular triglycerides in a concentration-dependent manner. The expression levels of the adipogenic, lipogenic, and lipolytic genes were decreased by CG-1 treatment, whereas the glycerol release level was not affected. When CG-1 was added into the medium during days 0-2 of 6-days-adipogenesis, the accumulation of intracellular lipids and the mRNA levels of the adipogenesis-related genes were decreased. In addition, the phosphorylation level of insulin receptor substrate-1 (IRS-1) and Akt in the early phase of adipocyte differentiation (within 1 day after initiating adipocyte differentiation) was reduced by CG-1. Furthermore, insulin-activated translocation of glucose transporter 4 to the plasma membranes in adipocytes was suppressed by CG-1, followed by decreased glucose uptake into the cells. These results indicate that an andiroba limonoid CG-1 suppressed the accumulation of intracellular lipids in the early phase of adipocyte differentiation through repression of IRS-1/Akt-mediated glucose uptake in adipocytes.

The Use of Medicinal Plants in the Riverside Community of the Mazagão River in the Brazilian Amazon, Amapá, Brazil: Ethnobotanical and Ethnopharmacological Studies

The inhabitants of the floodplain of the Mazagão River in the State of Amapá in the Brazilian Amazon have inherited from indigenous African and Cabocla cultures indications for the use and forms of preparation of medicinal plants to cure diseases of the body and spirit. This study aimed to perform an ethnopharmacological survey of medicinal plants used by the riparian community of the floodplains of the Mazagão River, in the State of Amapá. In this study, we chose semistructured interviews with socioeconomic, ethnopharmacological, and ethnobotanical aims. The collection of medicinal plants occurred during guided tours. The Use Value (UV), Informant Consensus Factor (ICF), Correction Factor (CF), and Fidelity level (FL) were calculated. There were 130 species of medicinal plants, distributed in 116 genera and 57 families; Fabaceae (16), Lamiaceae (14), Euphorbiaceae (7), and Arecaceae (6) include 33.33% of the total species sampled. All 95 native species of floodplain forests were previously described, and 35 are exotic species. The species with the highest UV (≥ 0.5) at the mouth of the Mazagão River were Carapa guianensis (0.91), Pentachlethra macroloba (0.83), Dalbergia subcymosa (0.77), Uncaria tomentosa (0.75), Otacanthus azureus (0.62), Virola surinamensis (0.62), Hura crepitans (0.58), Euterpe oleracea (0.56), and Arrabidaea chica (0.51). These species were also the ones that presented the highest ICF among the informants and 100% in FL for a specific therapeutic use. The study is comprised of 16 categories of therapeutic use, of which the majority of the plants used are related to diseases such as microbial infections (20.67%, 73 species), gastrointestinal disorders (13.31%), and inflammation (11.61%). The results showed that knowledge about the use of medicinal plants along the rivers and streams that form the mouth of the Mazagão River is evenly distributed. Most of the interviewees present diversified knowledge about the medicinal resources because they have a close relationship with the floodplain forest. Native species of this forest predominate among the most commonly used medicinal plants as subsidies for future pharmacological studies.

Pulsed high-dose dexamethasone modulates Th1-/Th2-chemokine imbalance in immune thrombocytopenia

Background

Chemokines and chemokine receptors play important roles in autoimmune diseases; however, their role in immune thrombocytopenia (ITP) is unclear. High-dose dexamethasone (HD-DXM) may become a first-line therapy for adult patients with ITP, but the effect of HD-DXM on chemokines in ITP patients is unknown. Our aim was to investigate the mechanism of pulsed HD-DXM for management of ITP, specifically regarding the chemokine pathways.

Methods

Th1-/Th2-associated chemokine and chemokine receptor profiles in ITP patients before and after pulsed HD-DXM was studied. Plasma levels of CCL5 and CXCL11 (Th1-associated) and of CCL11 (Th2-associated) were determined by ELISA. Gene expression of these three chemokines and their corresponding receptors CCR5, CXCR3, and CCR3, in peripheral blood mononuclear cells (PBMCs) was determined by quantitative RT-PCR.

Results

Thirty-three of the thirty-eight ITP patients responded effectively to HD-DXM (oral, 40 mg/day, 4 days). In ITP patients, plasma CXCL11 levels increased, while CCL11 and CCL5 decreased compared to controls (P < 0.05). Similarly, gene expression of CXCL11 and its receptor CXCR3 increased, while CCL11 and CCR3 decreased (P < 0.05). CCL5 expression did not significantly change; however, expression of its receptor CCR5 increased (P < 0.05). Interestingly, in the patients who responded to pulsed HD-DXM, CXCL11 and CXCR3 expression was down-regulated, while CCL11 and CCR3 expression was up-regulated (P < 0.05). Meanwhile, CCL5 expression was up-regulated and CCR5 was down-regulated by HD-DXM (P < 0.05).

Conclusions

The abnormal profiles of Th1-/Th2-associated chemokines and chemokine receptors may play important roles in the pathogenesis of ITP. Importantly, regulating Th1 polarization by pulsed HD-DXM may represent a novel approach for immunoregulation in ITP.

Gedunin Binds to Myeloid Differentiation Protein 2 and Impairs Lipopolysaccharide-Induced Toll-Like Receptor 4 Signaling in Macrophages

Recognition of bacterial lipopolysaccharide (LPS) by innate immune system is mediated by the cluster of differentiation 14/Toll-like receptor 4/myeloid differentiation protein 2 (MD-2) complex. In this study, we investigated the modulatory effect of gedunin, a limonoid from species of the Meliaceae family described as a heat shock protein Hsp90 inhibitor, on LPS-induced response in immortalized murine macrophages. The pretreatment of wild-type (WT) macrophages with gedunin (0.01-100 µM, noncytotoxic concentrations) inhibited LPS (50 ng/ml)-induced calcium influx, tumor necrosis factor-α, and nitric oxide production in a concentration-dependent manner. The selective effect of gedunin on MyD88-adapter-like/myeloid differentiation primary response 88- and TRIF-related adaptor molecule/TIR domain-containing adapter-inducing interferon-β-dependent signaling pathways was further investigated. The pretreatment of WT, TIR domain-containing adapter-inducing interferon-β knockout, and MyD88 adapter-like knockout macrophages with gedunin (10 µM) significantly inhibited LPS (50 ng/ml)-induced tumor necrosis factor-α and interleukin-6 production, at 6 hours and 24 hours, suggesting that gedunin modulates a common event between both signaling pathways. Furthermore, gedunin (10 µM) inhibited LPS-induced prostaglandin E2 production, cyclooxygenase-2 expression, and nuclear factor κB translocation into the nucleus of WT macrophages, demonstrating a wide-range effect of this chemical compound. In addition to the ability to inhibit LPS-induced proinflammatory mediators, gedunin also triggered anti-inflammatory factors interleukin-10, heme oxygenase-1, and Hsp70 in macrophages stimulated or not with LPS. In silico modeling studies revealed that gedunin efficiently docked into the MD-2 LPS binding site, a phenomenon further confirmed by surface plasmon resonance. Our results reveal that, in addition to Hsp90 modulation, gedunin acts as a competitive inhibitor of LPS, blocking the formation of the Toll-like receptor 4/MD-2/LPS complex.

In vitro and in vivo anti-malarial activity of limonoids isolated from the residual seed biomass from Carapa guianensis (andiroba) oil production

BACKGROUND

Carapa guianensis is a cultivable tree used by traditional health practitioners in the Amazon region to treat several diseases and particularly symptoms related to malaria. Abundant residual pressed seed material (RPSM) results as a by-product of carapa or andiroba oil production. The objective of this study was to evaluate the in vitro and in vivo anti-malarial activity and cytotoxicity of limonoids isolated from C. guaianensis RPSM.

METHODS

6α-acetoxyepoxyazadiradione (1), andirobin (2), 6α-acetoxygedunin (3) and 7-deacetoxy-7-oxogedunin (4) (all isolated from RPSM using extraction and chromatography techniques) and 6α-hydroxy-deacetylgedunin (5) (prepared from 3) were evaluated using the micro test on the multi-drug-resistant Plasmodium falciparum K1 strain. The efficacy of limonoids 3 and 4 was then evaluated orally and subcutaneously in BALB/c mice infected with chloroquine-sensitive Plasmodium berghei NK65 strain in the 4-day suppressive test.

RESULTS

In vitro, limonoids 1-5 exhibited median inhibition concentrations (IC50) of 20.7-5.0 μM, respectively. In general, these limonoids were not toxic to normal cells (MRC-5 human fibroblasts). In vivo, 3 was more active than 4. At oral doses of 50 and 100 mg/kg/day, 3 suppressed parasitaemia versus untreated controls by 40 and 66%, respectively, evidencing a clear dose-response.

CONCLUSION

6α-acetoxygedunin is an abundant natural product present in C. guianensis residual seed materials that exhibits significant in vivo anti-malarial properties.

γδ T Lymphocytes Coordinate Eosinophil Influx during Allergic Responses

Tissue eosinophil infiltration, which is a hallmark of allergic and helminthic diseases, is mainly coordinated by T lymphocytes, via the production of eosinophilotactic chemokines. Among T lymphocyte subsets, lymphocytes expressing γδ T cell receptor have been determined as a key factor for eosinophil accumulation via direct and indirect mechanisms. This knowledge is strongly supported by the fact that, in different experimental models of eosinophilic airway inflammation and helminth-induced Th2 lung inflammation, an evident tissue accumulation of γδ T lymphocytes is observed. In addition, the depletion of γδ T lymphocytes is correlated with the impairment of eosinophil accumulation in inflamed tissue. γδ T lymphocytes are non-conventional T lymphocytes, which comprise a minor T lymphocyte subset, mainly distributed in the tissue, and present crucial roles in innate and acquired immune responses. γδ T lymphocytes recognize several danger- and pathogen-associated molecular pattern molecules and stress antigens in a MHC-independent fashion and can provide rapid tissue-specific responses, via the production of a wide range of chemical mediators capable to modulate other cell populations. These mediators include chemoattractant cytokines and chemokines that attract eosinophils into the tissue by either direct recognition (such as IL-5, CCL11/eotaxin), or indirect mechanisms via the modulation of αβ T lymphocytes and macrophages (through the production of interferon-γ, IL-4, and CCL2/Monocyte chemoattractant protein-1, MCP-1, for example). The present review presents an overview of how γδ T lymphocytes coordinate eosinophil accumulation in allergy, by focusing on their role in airway inflammation and by discussing the involvement of cytokines and chemokines in this phenomenon.

Antimicrobial activity of Amazonian oils against Paenibacillus species

The Gram-positive, spore-forming bacterium Paenibacillus larvae is the primary bacterial pathogen of honeybee brood and the causative agent of American foulbrood disease (AFB). One of the feasible alternative treatments being used for their control of this disease is essential oils. In this study in vitro antimicrobial activity of Andiroba and Copaíba essential oils against Paenibacillus species, including P. larvae was evaluated. Minimal inhibitory concentration (MIC) in Mueller-Hinton broth by the microdilution method was assessed. Andiroba registered MIC values of 1.56-25%, while the MICs values obtained for Copaíba oil were of 1.56-12.5%. In order to determine the time-response effect of essential oils on P. larvae, this microorganism was exposed to the oils for up to 48 h. After 24 h treatment with Andiroba oil and after 48 h treatment with Copaíba oil no viable cells of P. larvae ATCC 9545 were observed. The possible toxic effect of essential oils were assessed by the spraying application method of the same concentrations of MICs. Bee mortality was evident only in treatment with Andiroba oil and the Copaíba oil shows no toxic effects after 10 days of observation. Taking together ours results showed for the first time that these oils presented a high activity against Paenibacillus species showing that Copaíba oil may be a candidate for the treatment or prevention of AFB.

Kidins220/ARMS contributes to airway inflammation and hyper-responsiveness in OVA-sensitized mice

BALB/c mice were sensitized and challenged with ovalbumin. We hypothesized that Kidins220/ARMS influences airway inflammation and hyper-responsiveness during allergic airway challenge, and assessed it by intranasal administration of anti-NGF antibody or anti-ARMS antibody to mice. Airway resistance was measured using a sealed whole-body plethysmograph. Total cell numbers and the percentage of different inflammatory cells in BALF were counted. Expression of IL-1β, IL-4 and TNF-α were determined by ELISA, and NF-κB activation determined by EMSA. Kidins220/ARMS expression was observed in ovalbumin-sensitized mice by immunofluorescence or western blotting. IL-1β, IL-4, and TNF-α were overexpressed and NF-κB activation increased after allergen challenge compared with controls. After treatment with anti-ARMS or anti-NGF, levels of IL-1β, IL-4 and TNF-α and NF-κB activation were reduced in comparison with those of ovalbumin-sensitized mice. These results suggest that NGF-mediated Kidins220/ARMS signaling participates in the pathogenesis of asthma, and contributes to airway inflammation and hyper-responsiveness in ovalbumin-sensitized mice.

A natural compound, methyl angolensate, induces mitochondrial pathway of apoptosis in Daudi cells

Natural products discovered from medicinal plants have played an important role in the treatment of cancer. In an effort to identify novel small molecules which can affect the proliferation of lymphoma cells, we tested methyl angolensate (MA), a plant derived tetranortriterpenoid, purified from the crude extract of the root callus of Soymida febrifuga commonly known as Indian red wood tree. We have tested MA for its cytotoxic properties on Burkitt's lymphoma cell lines, using various cellular assays. We observed that MA induces cytotoxicity in Daudi cells in a dose-dependent manner using trypan blue, MTT and LDH assays. We find that the treatment with MA led to activation of DNA double-strand break repair proteins including KU70 and KU80, suggesting the activation of nonhomologous DNA end joining pathway in surviving cells. Further, we find that methyl angolensate could induce apoptosis by cell cycle analysis, annexin V-FITC staining, DNA fragmentation and PARP cleavage. Besides, MA treatment led to reactive oxygen species generation and loss of mitochondrial transmembrane potential. These results suggest the activation of mitochondrial pathway of apoptosis. Hence, we identify MA as a potential chemotherapeutic agent against Daudi cells.

Celastrol suppresses allergen-induced airway inflammation in a mouse allergic asthma model

Celastrol has anti-inflammatory and immunomodulatory activities, but its anti-allergic effects remain poorly understood. Therefore, we aimed to investigate the ability of celastrol to inhibit asthmatic reactions in a mouse allergic asthma model. BALB/c mice were sensitized and challenged with ovalbumin to induce asthma. We measured the recruitment of inflammatory cells into the bronchoalveolar lavage fluid or lung tissues by Diff-Quik and hematoxylin and eosin staining, respectively, goblet cell hyperplasia by periodic acid-Schiff (PAS) staining, airway hyperresponsiveness by Flexvent system, mRNA and protein expression of cytokines, matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) by reverse transcriptase polymerase chain reaction and ELISA, respectively, and the activities of mitogen-activated protein (MAP) kinases and nuclear factor-kappa B (NF-kappaB) in the bronchoalveolar lavage cells and lung tissues by Western blot and electrophoretic mobility shift assay (EMSA), respectively. Celastrol reduced the total number of inflammatory cells in the bronchoalveolar lavage fluid and in peribronchial areas, and decreased the airway hyperresponsiveness, mRNA and protein expression levels for inflammatory cytokines such as interleukin (IL)-4, IL-13, TNF-alpha and IFN-gamma, and for MMPs and TIMPs, MAP kinases and NF-kappaB activities in the bronchoalveolar lavage cells and in the lung tissues increased in ovalbumin-induced allergic asthma in mice. Our data suggest that oral administration of celastrol suppresses ovalbumin-induced airway inflammation, hyperresponsiveness, and tissue remodeling by regulating the imbalance of MMP-2/-9 and TIMP-1/-2 by inflammatory cytokines via MAP kinases/NF-kappaB in inflammatory cells. Based on our findings, we suggest that celastrol may be used as a therapeutic agent for allergy-induced asthma.

Pelioid-type hepatocellular carcinoma with numerous eosinophilic infiltrations in a patient with primary biliary cirrhosis

A 65-year-old woman with liver injury was referred to our hospital in 1992. She was diagnosed with primary biliary cirrhosis (PBC) of Scheuer's histological classification stage IV. She was treated with 600 mg/day of ursodeoxycholic acid. A 1-cm mass in S7 was detected in August 1995. The serum alpha-fetoprotein (AFP) level increased to 1288 ng/mL in January 1996. Angiography showed a cotton wool-like appearance in the delayed phase. Because the size of the tumor appeared to be increasing and the serum AFP levels increased with high levels of L3 fraction, a pelioid-type hepatocellular carcinoma (HCC) was strongly suspected. Hepatic artery infusion with SMANCS and partial resection of S7 and S8 of the liver were performed in March 1996. The pathological diagnosis for theresected liver tumor was pelioid-type HCC. The serum AFP level decreased to 50 ng/mL after the operation, but relapsed HCC was detected in S6 and S7. Angiography in September 1996 revealed multiple hypervascular lesions, and hepatic artery infusion with SMANCS was again performed; however, we were unable to suppress the progression of the relapsed HCC. The patient died due to an intra-abdominal rupture of relapsed HCC and subsequent liver failure in December 1996. We report a rare case of pelioid-type HCC with numerous eosinophilic infiltrations arising from PBC.

Acute and subacute toxicity of the Carapa guianensis Aublet (Meliaceae) seed oil

Carapa guianensis (Meliaceae), known as Andiroba in Brazil, has been used by Amazon Rainforest indigenous communities for treatment of coughs, convulsions, skin diseases, arthritis, rheumatism, ear infections, to heal wounds and bruises and as an insect repellent. Carapa guianensis seed oil (SO) was evaluated for its acute and subacute toxicity (30 days) by the oral route in Wistar rats. In the acute toxicity test, SO (0.625-5.0g/kg, n=5/sex) did not produce any hazardous symptoms or deaths. The subacute treatment with SO (0.375, 0.75 and 1.5g/kg, n=10/group) failed to change body weight gain, food and water consumption. Hematological analysis showed no significant differences in any of the parameters examined. However, in the biochemical parameters, there was an increase in the alanine aminotransferase (ALT) serum level (29%) in the group SO 1.5g/kg. In addition, absolute and relative liver weights were increased at the doses of 0.75g/kg (23.4 and 19.1%) and 1.5g/kg (18.7 and 33.1%). In conclusion, acute and subacute administration of Carapa guianensis seed oil did not produce toxic effects in male Wistar rats. However, the increase in the ALT serum level and in both absolute and relative liver weights may indicate a possible hepatic toxicity.

Discovery of agents that eradicate leukemia stem cells using an in silico screen of public gene expression data

Increasing evidence indicates that malignant stem cells are important for the pathogenesis of acute myelogenous leukemia (AML) and represent a reservoir of cells that drive the development of AML and relapse. Therefore, new treatment regimens are necessary to prevent relapse and improve therapeutic outcomes. Previous studies have shown that the sesquiterpene lactone, parthenolide (PTL), ablates bulk, progenitor, and stem AML cells while causing no appreciable toxicity to normal hematopoietic cells. Thus, PTL must evoke cellular responses capable of mediating AML selective cell death. Given recent advances in chemical genomics such as gene expression-based high-throughput screening (GE-HTS) and the Connectivity Map, we hypothesized that the gene expression signature resulting from treatment of primary AML with PTL could be used to search for similar signatures in publicly available gene expression profiles deposited into the Gene Expression Omnibus (GEO). We therefore devised a broad in silico screen of the GEO database using the PTL gene expression signature as a template and discovered 2 new agents, celastrol and 4-hydroxy-2-nonenal, that effectively eradicate AML at the bulk, progenitor, and stem cell level. These findings suggest the use of multicenter collections of high-throughput data to facilitate discovery of leukemia drugs and drug targets.

A toxicological evaluation of the effect of Carapa guianensis Aublet on pregnancy in Wistar rats

The effects of the administration of Carapa guianensis Aublet (Meliaceae) seed oil were investigated during pregnancy in female Wistar rats. Five groups of pregnant rats (n=5-9 per group) were treated orally from the 7th to the 14th day of pregnancy (organogenic period), at doses of: 0, 0.375, 0.75, 1.5 and 3.0gkg(-1). On the 20th day of pregnancy, the animals were sacrificed and laparotomized to evaluate reproductive parameters. The results showed that there was no difference between the control and treated groups in terms of the number of live and dead fetuses, the dam-offspring relationship, the weight of the fetus, the weight of the placentae and ovaries, the number of implantation sites, the number of resorption sites, the number of corpora lutea in the ovaries, and the pre- and post-implantation loss rates. It is therefore concluded that administration of Carapa guianensis seed oil did not bring about any toxic effect on pregnancy in Wistar rats.

Gedunin, a limonoid from Xylocarpus granatum, inhibits the growth of CaCo-2 colon cancer cell line In Vitro

Xylocarpus granatum J. König (Meliaceae), commonly known as 'dhundul', is a Bangladeshi mangrove tree, and well distributed in a number of other countries of south-east Asia, Australia and east Africa. Traditionally, X. granatum has been used as an astringent and febrifuge, and also for the treatment of fever, malaria, thrush, cholera, dysentery and diarrhoea in many countries including Bangladesh. Two limonoids, gedunin and 1alpha-hydroxy-1,2-dihydrogedunin, the latter being new, have been isolated from the bark of Xylocarpus granatum by reversed-phase preparative HPLC, and the structures were confirmed by spectroscopic means. The cytotoxic potential of gedunin has been evaluated by the Promega's CellTiter 96 non-radioactive cell proliferation assay using the CaCo-2 colon cancer cell line (IC(50) = 16.83 microM). A summary of the biological activities of gedunin reported to date is also presented.