Potent anti-inflammatory effects of systemically administered curcumin modulate periodontal disease in vivo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of the antiulcerogenic and analgesic activities of Cordia verbenacea DC. (Boraginaceae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Monoamine oxidase inhibitory activities of indolylalkaloid toxins from the venom of the colonial spider Parawixia bistriata: Functional characterization of PwTX-I

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The Venomics of Bothrops alternatus is a Pool of Acidic Proteins with Predominant Hemorrhagic and Coagulopathic Activities

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro targeting of Polo-like kinase 1 in bladder carcinoma: Comparative effects of four potent inhibitors

Despite the improvements in neoadjuvant chemotherapy, the outcome of patients with advanced bladder cancer has changed very little over the past 30 years. In the present study we tested and compared the in vitro antitumor activities of four different inhibitors of Polo-like kinase 1 (PLK1) (BI 2536, BI 6727, GW843682X, and GSK461364), against 3 bladder carcinoma cell lines RT4, 5637 and T24. The impact on radiosensitivity and drug interactions in simultaneous treatments with cisplatin, methotrexate, and doxorubicin were also investigated. Our results showed that PLK1 inhibition prevented cell proliferation and clonogenicity, causing significant inhibition of invasion of tumor cells, though modest differences were observed between drugs. Moreover, all PLK1 inhibitors induced G2/M arrest, with the subsequent induction of death in all 3 cell lines. Drug interactions studies showed auspicious results for all PLK1 inhibitors when combined with the commonly used cisplatin and methotrexate, though combinations with doxorubicin showed mostly antagonistic effects. Comparably, the four PLK1 inhibitors efficiently sensitized cells to ionizing radiation. Our findings demonstrate that irrespective of the inhibitor used, the pharmacological inhibition of PLK1 constrains bladder cancer growth and dissemination, providing new opportunities for future therapeutic intervention. However, further laboratorial and preclinical tests are still needed to corroborate the usefulness of using them in combination with other commonly used chemotherapeutic drugs. © 2013 Landes Bioscience.

Zoledronic Acid Inhibits Human Osteoblast Activities

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Protease-inhibiting, molecular modeling and antimicrobial activities of extracts and constituents from Helichrysum foetidum and Helichrysum mechowianum (compositae)

Background Helichrysum species are used extensively for stress-related ailments and as dressings for wounds normally encountered in circumcision rites, bruises, cuts and sores. It has been reported that Helichysum species are used to relief abdominal pain, heart burn, cough, cold, wounds, female sterility, menstrual pain. Results From the extracts of Helichrysum foetidum (L.) Moench, six known compounds were isolated and identified. They were 7, 4′-dihydroxy-5-methoxy-flavanone (1), 6′-methoxy-2′,4, 4′-trihydroxychalcone (2), 6′-methoxy-2′,4-dihydroxychalcone -4′-O-β-D-glucoside (3), apigenin (4), apigenin-7-O-β-D-glucoside (5), kaur-16-en-18-oic acid (6) while two known compounds 3,5,7-trihydroxy-8-methoxyflavone (12), 4,5-dicaffeoyl quinic acid (13) together with a mixture of phytosterol were isolated from the methanol extract of Helichrysum mechowianum Klatt. All the compounds were characterized by spectroscopic and mass spectrometric methods, and by comparison with literature data. Both extracts and all the isolates were screened for the protease inhibition, antibacterial and antifungal activities. In addition, the phytochemical profiles of both species were investigated by ESI-MS experiments. Conclusions These results showed that the protease inhibition assay of H. foetidum could be mainly attributed to the constituents of flavonoids glycosides (3, 5) while the compound (13) from H. mechowianum contributes to the stomach protecting effects. In addition, among the antibacterial and antifungal activities of all the isolates, compound (6) was found to possess a potent inhibitor effect against the tested microorganisms. The heterogeneity of the genus is also reflected in its phytochemical diversity. The differential bioactivities and determined constituents support the traditional use of the species. Molecular modelling was carried out by computing selected descriptors related to drug absorption, distribution, metabolism, excretion and toxicity (ADMET).

The chemical composition and pharmacological activities of geopropolis produced by Melipona fasciculata Smith in northeast Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Disabling c-Myc in childhood medulloblastoma and atypical teratoid/rhabdoid tumor cells by the potent G-quadruplex interactive agent S2T1-6OTD

We investigated here the effects of S2T1-6OTD, a novel telomestatin derivative that is synthesized to target G-quadruplex-forming DNA sequences, on a representative panel of human medulloblastoma (MB) and atypical teratoid/rhabdoid (AT/RT) childhood brain cancer cell lines. S2T1-6OTD proved to be a potent c-Myc inhibitor through its high-affinity physical interaction with the G-quadruplex structure in the c-Myc promoter. Treatment with S2T1-6OTD reduced the mRNA and protein expressions of c-Myc and hTERT, which is transcriptionally regulated by c-Myc, and decreased the activities of both genes. In remarkable contrast to control cells, short-term (72-hour) treatment with S2T1-6OTD resulted in a dose- and time-dependent antiproliferative effect in all MB and AT/RT brain tumor cell lines tested (IC(50), 0.25-0.39 micromol/L). Under conditions where inhibition of both proliferation and c-Myc activity was observed, S2T1-6OTD treatment decreased the protein expression of the cell cycle activator cyclin-dependent kinase 2 and induced cell cycle arrest. Long-term treatment (5 weeks) with nontoxic concentrations of S2T1-6OTD resulted in a time-dependent (mainly c-Myc-dependent) telomere shortening. This was accompanied by cell growth arrest starting on day 28 followed by cell senescence and induction of apoptosis on day 35 in all of the five cell lines investigated. On in vivo animal testing, S2T1-6OTD may well represent a novel therapeutic strategy for childhood brain tumors.

Contribution of mucosal maltase-glucoamylase activities to mouse small intestinal starch alpha-glucogenesis

Digestion of starch requires activities provided by 6 interactive small intestinal enzymes. Two of these are luminal endo-glucosidases named alpha-amylases. Four are exo-glucosidases bound to the luminal surface of enterocytes. These mucosal activities were identified as 4 different maltases. Two maltase activities were associated with sucrase-isomaltase. Two remaining maltases, lacking other identifying activities, were named maltase-glucoamylase. These 4 activities are better described as alpha-glucosidases because they digest all linear starch oligosaccharides to glucose. Because confusion persists about the relative roles of these 6 enzymes, we ablated maltase-glucoamylase gene expression by homologous recombination in Sv/129 mice. We assayed the alpha-glucogenic activities of the jejunal mucosa with and without added recombinant pancreatic alpha-amylase, using a range of food starch substrates. Compared with wild-type mucosa, null mucosa or alpha-amylase alone had little alpha-glucogenic activity. alpha-Amylase amplified wild-type and null mucosal alpha-glucogenesis. alpha-Amylase amplification was most potent against amylose and model resistant starches but was inactive against its final product limit-dextrin and its constituent glucosides. Both sucrase-isomaltase and maltase-glucoamylase were active with limit-dextrin substrate. These mucosal assays were corroborated by a 13C-limit-dextrin breath test. In conclusion, the global effect of maltase-glucoamylase ablation was a slowing of rates of mucosal alpha-glucogenesis. Maltase-glucoamylase determined rates of digestion of starch in normal mice and alpha-amylase served as an amplifier for mucosal starch digestion. Acarbose inhibition was most potent against maltase-glucoamylase activities of the wild-type mouse. The consortium of 6 interactive enzymes appears to be a mechanism for adaptation of alpha-glucogenesis to a wide range of food starches.

Transmembrane tumor necrosis factor is a potent inducer of colitis even in the absence of its secreted form

Tumor necrosis factor (TNF) is cleaved proteolytically from a 26-kilodalton transmembrane precursor protein into secreted 17-kilodalton monomers. Transmembrane (tm) and secreted trimeric TNF are biologically active and may mediate distinct activities. We assessed the consequences of a complete inhibition of TNF processing on the course of colitis in recombination activating gene (RAG)2 -/- mice on transfer of CD4 CD45RB hi T cells.

Dual Targeting of Tumor Angiogenesis and Chemotherapy by Endostatin- Cytosine Deaminase-Uracil PhosphoribosylTransferase

Antiangiogenesis is a promising anti-tumor strategy through inhibition tumor vascularformation to suppress tumor growth. Targeting specific VEGF/R has been showntherapeutic benefits in many cancer types and become a first approvedantiangiogenic modalities by Food and Drug Administration (FDA) in United States.However, interruption of homeostasis in normal tissues that is likely due to theinhibition of VEGF/R signaling pathway induces unfavorable side effects. Moreover,cytostatic nature of antiangiogenic drugs frequently causes less tumor cell specifickilling activity, and cancer cells escaped from cell death induced by these drugseven gain more malignant phenotypes, resulting in tumor invasion and metastasis.To overcome these issues, we developed a novel anti-tumor therapeutic EndoCDfusion protein which linked endostatin (Endo) to cytosine deaminase-uracilvphosphoribosyl transferase (CD). Endo targets unique tumor endothelial cells toprovide tumor-specific antiangiogenesis activity and also carries CD to the localtumor area, where it serves nontoxic prodrug 5-fluorocytosine (5-FC) enzymaticconversion reaction to anti-metabolite chemotherapy drug 5-fluorouracil (5-FU). Wedemonstrated that 5-FU concentration was highly increased in tumor sites, resultingin high level of endothelial cells and tumor cells cytotoxic efficacy. Furthermore,EndoCD/5-FC therapy decreased tumor growth and colorectal liver metastasisincident compared with bevacizumab/5-FU treatment in human breast and colorectalliver metastasis orthotropic animal models. In cardiotoxicity safety profile,EndoCD/5-FC is a contrast to bevacizumab/5-FU; lower risk of cardiotoxicityinduction or heart function failure was found in EndoCD/5-FC treatment thanbevacizumab/5-FU does in mice. EndoCD/5-FC showed more potent therapeuticefficacy with high safety profile and provided stronger tumor invasion or metastasisinhibition than antiangiogenic drugs. Together, EndoCD fusion protein with 5-FCshowed dual tumor targeting activities including antiangiogenesis and tumor localchemotherapy, and it could serve as an alternative option for antiangiogenic therapy.

Inhibition of interferon γ induced interleukin 12 production: A potential mechanism for the anti-inflammatory activities of tumor necrosis factor

Inflammation is associated with production of cytokines and chemokines that recruit and activate inflammatory cells. Interleukin (IL) 12 produced by macrophages in response to various stimuli is a potent inducer of interferon (IFN) γ production. IFN-γ, in turn, markedly enhances IL-12 production. Although the immune response is typically self-limiting, the mechanisms involved are unclear. We demonstrate that IFN-γ inhibits production of chemokines (macrophage inflammatory proteins MIP-1α and MIP-1β). Furthermore, pre-exposure to tumor necrosis factor (TNF) inhibited IFN-γ priming for production of high levels of IL-12 by macrophages in vitro. Inhibition of IL-12 by TNF can be mediated by both IL-10-dependent and IL-10-independent mechanisms. To determine whether TNF inhibition of IFN-γ-induced IL-12 production contributed to the resolution of an inflammatory response in vivo, the response of TNF+/+ and TNF−/− mice injected with Corynebacterium parvum were compared. TNF−/− mice developed a delayed, but vigorous, inflammatory response leading to death, whereas TNF+/+ mice exhibited a prompt response that resolved. Serum IL-12 levels were elevated 3-fold in C. parvum-treated TNF−/− mice compared with TNF+/+ mice. Treatment with a neutralizing anti-IL-12 antibody led to resolution of the response to C. parvum in TNF−/− mice. We conclude that the role of TNF in limiting the extent and duration of inflammatory responses in vivo involves its capacity to regulate macrophage IL-12 production. IFN-γ inhibition of chemokine production and inhibition of IFN-γ-induced IL-12 production by TNF provide potential mechanisms by which these cytokines can exert anti-inflammatory/repair function(s).

Caffeic acid phenethyl ester is a potent and specific inhibitor of activation of nuclear transcription factor NF-kappa B.

Caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is known to have antimitogenic, anticarcinogenic, antiinflammatory, and immunomodulatory properties. The molecular basis for these diverse properties is not known. Since the role of the nuclear factor NF-kappa B in these responses has been documented, we examined the effect of CAPE on this transcription factor. Our results show that the activation of NF-kappa B by tumor necrosis factor (TNF) is completely blocked by CAPE in a dose- and time-dependent manner. Besides TNF, CAPE also inhibited NF-kappa B activation induced by other inflammatory agents including phorbol ester, ceramide, hydrogen peroxide, and okadaic acid. Since the reducing agents reversed the inhibitory effect of CAPE, it suggests the role of critical sulfhydryl groups in NF-kappa B activation. CAPE prevented the translocation of the p65 subunit of NF-kappa B to the nucleus and had no significant effect on TNF-induced I kappa B alpha degradation, but did delay I kappa B alpha resynthesis. The effect of CAPE on inhibition of NF-kappa B binding to the DNA was specific, in as much as binding of other transcription factors including AP-1, Oct-1, and TFIID to their DNA were not affected. When various synthetic structural analogues of CAPE were examined, it was found that a bicyclic, rotationally constrained, 5,6-dihydroxy form was superactive, whereas 6,7-dihydroxy variant was least active. Thus, overall our results demonstrate that CAPE is a potent and a specific inhibitor of NF-kappa B activation and this may provide the molecular basis for its multiple immunomodulatory and antiinflammatory activities.

Antimycobacterial activities of antisense oligodeoxynucleotide phosphorothioates in drug-resistant strains.

Strains of Mycobacterium smegmatis, a mycobacterium which shares genetic sequences, grows more rapidly, and is nonpathogenic in man as compared with Mycobacterium tuberculosis, were utilized for the initial development of new antimycobacterial therapy. Drug-resistant strains of M. smegmatis which are known to arise in a manner identical to the emergence of drug-resistant strains of M. tuberculosis were isolated and utilized as models for the antimycobacterial activities of modified and unmodified oligodeoxynucleotide phosphorothioates in broth cultures. Under normal conditions, oligodeoxynucleotide phosphorothioates do not enter mycobacteria, and several strategies were successfully utilized to afford entry of oligonucleotides into the mycobacterial cells. One involved the presence of very low levels of ethambutol, which enables the entry of oligonucleotides into mycobacteria because of its induced alterations in the cell wall, and another involved the utilization of oligonucleotides covalently attached to a D-cycloserine molecule, whereby entry into the mycobacterial cell is achieved by a receptor-mediated process. Another low molecular weight, covalently attached ligand that enabled the entry and subsequent antimycobacterial activities of oligodeoxynucleotide phosphorothioates in the absence of a cell wall modifying reagent was biotin. Significant sequence-specific growth inhibition of wild-type, as well as of drug-resistant, M. smegmatis was obtained by modified oligonucleotides complementary in sequence to a specific region of the mycobacterium aspartokinase (ask) gene when utilized in combinations with ethambutol (as compared to ethambutol alone) or as D-cycloserine or biotin covalent adducts without the presence of any other cytotoxic or cytostatic agent.