Profiling target engagement and cellular uptake of cRGD-decorated clinical-stage core-crosslinked polymeric micelles

Polymeric micelles are increasingly explored for tumor-targeted drug delivery. CriPec® technology enables the generation of core-crosslinked polymeric micelles (CCPMs) based on thermosensitive (mPEG-b-pHPMAmLacn) block copolymers, with high drug loading capacity, tailorable size, and controlled drug release kinetics. In this study, we decorated clinical-stage CCPM with the αvβ3 integrin-targeted cyclic arginine-glycine-aspartic acid (cRGD) peptide, which is one of the most well-known active targeting ligands evaluated preclinically and clinically. Using a panel of cell lines with different expression levels of the αvβ3 integrin receptor and exploring both static and dynamic incubation conditions, we studied the benefit of decorating CCPM with different densities of cRGD. We show that incubation time and temperature, as well as the expression levels of αvβ3 integrin by target cells, positively influence cRGD-CCPM uptake, as demonstated by immunofluorescence staining and fluorescence microscopy. We demonstrate that even very low decoration densities (i.e., 1 mol % cRGD) result in increased engagement and uptake by target cells as compared to peptide-free control CCPM, and that high cRGD decoration densities do not result in a proportional increase in internalization. In this context, it should be kept in mind that a more extensive presence of targeting ligands on the surface of nanomedicines may affect their pharmacokinetic and biodistribution profile. Thus, we suggest a relatively low cRGD decoration density as most suitable for in vivo application

Psidium guajava L. (popular name guava) in vitro and in vivo anticancer activity

Orientadores: João Ernesto de Carvalho, Mary Ann FoglioDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de BiologiaResumo: A pesquisa de drogas anticâncer através da triagem de extratos e princípios ativos obtidos de fontes naturais possibilitou a descoberta e o desenvolvimento de diversos quimioterápicos hoje utilizados no tratamento do câncer. Este projeto teve como objetivo avaliar a atividade anticâncer de Psidium guajava L. (nome popular: goiabeira), espécie eleita através de levantamento etnofarmacológico para atividade antiparasitária. Após a colheita, o material vegetal foi submetido a um processo de extração a quente por Soxhlet, com diclorometano e etanol 95%, originando o extrato bruto diclorometânico (EBD) e etanólico (EBE), respectivamente. O extrato bruto ativo, EBD, foi submetido a diversos fractionamentos biomonitorados, até a obtenção de uma fração enriquecida nos meroterpenos guajadial, psidial A e seus isômeros, princípios ativos da espécie vegetal. Todas as amostras (extratos brutos e frações enriquecidas) tiveram sua potencial atividade anticâncer avaliadas in vitro frente a um painel de dez linhagens tumorais humanas, cedidas pelo National Cancer Institute (NCI, Estados Unidos), a saber: K562 (leucemia), MCF-7 (mama), NCI/ADR-RES (ovário resistente a múltiplas drogas), NCI-H460 (pulmão), UACC62 (melanoma), PC-3 (próstata), HT-29 (cólon), OVCAR-03 (ovário), U251 (glioma) and 786-0 (rim). A fração ativa enriquecida nos meroterpenos foi avaliada in vivo no tumor sólido de Ehrlich, em camundongos Balb/C, reduzindo significativamente o crescimento tumoral. Além da atividade antitumoral observada in vivo, a análise macroscópica do útero indicou aumento em tamanho e peso em relação aos grupos controle negativo (salina) e positivo (doxorrubicina). As moléculas de guajadial e psidial A apresentam propriedades físico-químicas semelhantes ao estradiol e ao tamoxifeno e estudos de docking molecular sugerem que ambos os compostos se liguem no sítio de ligação no receptor de estrógeno (ER), analogamente ao tamoxifeno. A capacidade de reduzir o crescimento tumoral e, ao mesmo tempo, estimular o útero indicam que guajadial e psidial A possivelmente agem como fitoestrógenos, possuindo um mecanismo de ação semelhante ao tamoxifeno, atuando como SERMs (Selective Estrogen Receptor Modulators) e agindo como agonistas e antagonistas de forma tecido específicaAbstract: Anticancer drug research based on screening of natural sources enabled the discovery of several drugs that are used in cancer treatment. This project aimed to evaluate the in vitro and in vivo anticancer activity of Psidium guajava L. (popular name: guava), elected for its ethnopharmacological use for antiparasitic activity. After harvesting, the vegetal material was extracted in Soxhlet with dicloromethane and then ethanol 95%, leading to the dicloromethane crude extract (DCE) and the ethanolic crude extract (ECE), respectively.The active extract, DCE, was submitted to several biomonitored fractionating processes and an active mixture of meroterpenes identified guajadial, psidial A and its isomers as active principles. All samples (crude extract and enriched fractions) were evaluated in vitro for cytotoxic activity against ten human cancer lines (donated by National Cancer Institute, USA): K562 (leukemia), MCF-7 (breast), NCI/ADR-RES (resistant ovarian cancer), NCI-H460 (lung), UACC62 (melanoma), PC-3 (prostate), HT-29 (colon), OVCAR-03 (ovary), U251 (glioma) and 786-0 (kidney). Meroterpenes enriched fraction was evaluated in vivo in the Solid Ehrlich Tumor, in Balb/C mice, and significantly reduced tumor growth. Besides antitumoral activity, macroscopic analysis of uterus showed increased size and weight in comparison to both negative (vehicle) and positive (doxorubicin) control groups. The molecules of guajadial and psidial A display similar physicochemical properties to estradiol and tamoxifen and in silico molecular docking studies suggest that both molecules bind to the estrogen-binding site of ERs analogously to tamoxifen. The ability to reduce breast cancer tumor growth and stimulate the uterus suggests that guajadial and psidial A may act as phytoestrogens, giving insights for a mechanism of action similar to tamoxifen, acting as SERMs (Selective Estrogen Receptor Modulators), having both agonist and antagonist tissue-specific activitiesMestradoHistologiaMestre em Biologia Celular e Estrutura

ComposiÇço Farmaceutica Para O Tratamento De CÂncer A Partir De Principios Ativos De Psidium Guajava L.

COMPOSIÇÃO FARMACÊUTICA PARA O TRATAMENTO DE CÂNCER A PARTIR DE PRINCÍPIOS ATIVOS ISOLADOS DE PSIDIUM GUAJAVA L. O presente invento refere-se à urna composição farmacêutica que compreende a molécula guajadial (mlz=474, íon base = 271) obtida da espécie vegetal Psidium guajava L. (nome popular: goiabeira) da família Myrtaceae, que possui atividade anticâncer.BRPI1003652 (A2); BRPI1003652 (C1)BR2010PI0365

In Vitro And In Vivo Anticancer Activity Of Extracts, Fractions, And Eupomatenoid-5 Obtained From Piper Regnellii Leaves.

Despite numerous studies with the Piper genus, there are no previous results reporting in vitro or in vivo Piper regnellii (Miq.) C. DC. var. regnellii anticancer activity. The aim of this study was to investigate P. regnellii in vitro and in vivo anticancer activity and further identify its active compounds. In vitro antiproliferative activity was evaluated in 8 human cancer cell lines: melanoma (UACC-62), breast (MCF7), kidney (786-0), lung (NCI-H460), prostate (PC-3), ovary (OVCAR-3), colon (HT29), and leukemia (K-562). Total growth inhibition (TGI) values were chosen to measure antiproliferative activity. Among the cell lines evaluated, eupomatenoid-5 demonstrated better in vitro antiproliferative activity towards prostate, ovary, kidney, and breast cancer cell lines. In vivo studies were carried out with Ehrlich solid tumor on Balb/C mice treated with 100, 300, and 1000 mg/kg of P. regnellii leaves dichloromethane crude extract (DCE), with 30 and 100 mg/kg of the active fraction (FRB), and with 30 mg/kg of eupomatenoid-5. The i. p. administration of DCE, FRB, and eupomatenoid-5 significantly inhibited tumor progression in comparison to control mice (saline). Therefore, this study showed that neolignans of Piper regnellii have promising anticancer activity. Further studies will be undertaken to determine the mechanism of action and toxicity of these compounds.771482-

Bone resorption and body reorganization during maturation induce maternal transfer of toxic metals in anguillid eels

During their once-in-a-lifetime transoceanic spawning migration, anguillid eels do not feed, instead rely on energy stores to fuel the demands of locomotion and reproduction while they reorganize their bodies by depleting body reserves and building up gonadal tissue. Here we show how the European eel (Anguilla anguilla) breaks down its skeleton to redistribute phosphorus and calcium from hard to soft tissues during its sexual development. Using multiple analytical and imaging techniques, we characterize the spatial and temporal degradation of the skeletal framework from initial to final gonadal maturation and use elemental mass ratios in bone, muscle, liver, and gonadal tissue to determine the fluxes and fates of selected minerals and metals in the eels' bodies. We find that bone loss is more pronounced in females than in males and eventually may reach a point at which the mechanical stability of the skeleton is challenged. P and Ca are released and translocated from skeletal tissues to muscle and gonads, leaving both elements in constant proportion in remaining bone structures. The depletion of internal stores from hard and soft tissues during maturation-induced body reorganization is accompanied by the recirculation, translocation, and maternal transfer of potentially toxic metals from bone and muscle to the ovaries in gravid females, which may have direct deleterious effects on health and hinder the reproductive success of individuals of this critically endangered species