Investigating the individual and mixture cytotoxicity of co-occurring aflatoxin B1, enniatin B, and sterigmatocystin on gastric, intestinal, hepatic, and renal cellular models.

This study investigates the individual and combined effects of the mycotoxins, Aflatoxin B1 (AFB1), Enniatin B (ENNB) and Sterigmatocystin (STG), on the cellular viability of gastric (NCI-N87), intestinal (Caco-2), hepatic (Hep-G2) and renal (Hek-293) cells, shedding light on synergistic or antagonistic effects using a constant ratio combination design proposed by Chou-Talalay. These toxins are prevalent in cereal-based foods, frequently consumed by children which raises concerns about their exposure to these mycotoxins. This population is particularly vulnerable to the effects of these toxins due to their underdeveloped organs and incompletely structured physiological processes. Results showed that ENB was the most toxic of the three mycotoxins across all cell lines, while STG and AFB1 showed lower toxicity. The combination of ENNB + STG was found to be the most potent in terms of binary mixtures. In regard to ternary combinations, Caco-2 cells are more sensitive to the tested mycotoxins, whereas NCI-N87 cells show lower levels of cell damage. Worrying dose reduction values (>10-fold) were found for ENNB in binary and ternary combinations at low exposure levels. These findings are significant for establishing initial reference values, which play a pivotal role in estimating reference doses that are subsequently incorporated into the broader risk assessment process.

Recreational MDMA doses do not elicit hepatotoxicity in HepG2 spheroids under normo- and hyperthermia.

MDMA (3,4-methylenedioxymethamphetamine), an entactogen with empathogenic and prosocial effects, is widely used in music festivals and other festive settings. High MDMA doses have been associated with drug-induced liver injury and cases of hyperthermia. Although the latter condition is thought to increase MDMA hepatotoxicity, this correlation remains poorly explored for recreational MDMA doses. On the other hand, the fact that MDMA acts to extinguish fear and to reconsolidate memory could be explored as an adjunct to psychotherapy during treatment of neuropsychiatric disorders such as post-traumatic stress disorder. In this context, assessing MDMA toxicity is relevant, and tridimensional cell culture has emerged as an alternative to animal models in toxicity assessment. Herein, we have used HepG2 spheroids to evaluate MDMA-induced hepatotoxicity at recreational doses, under normo- or hyperthermia. The MTT reduction assay did not evidence significantly reduced cell viability. Moreover, MDMA did not increase reactive oxygen species production, deplete the mitochondrial membrane potential, arrest the cell cycle, or induce apoptotic cell death. These findings support further pre-clinical investigation of MDMA safety from the perspective of both harm reduction and therapy given that non-abusive recreational and therapeutic doses overlap.

Aspectos inmunológicos en preeclampsia / Immunologic Aspects in Preeclampsia

Resumen La preeclampsia es una patología con alta morbimortalidad a nivel mundial. En esta enfermedad la placenta es un órgano de choque donde la inflamación y la respuesta inmunológica generan el daño que se traduce en el cuadro clínico característico. La tríada clásica en preeclampsia está integrada por hipertensión, edema y proteinuria, por lo que se piensa que el endotelio debe estar afectado por la actividad inflamatoria-inmunológica. El sistema inmunológico actúa en el desarrollo del embarazo y lo hace a diferentes tiempos y regulando de manera fisiológica. Tanto componentes celulares como humorales de la respuesta innata y adquirida han sido estudiados en pacientes con preeclampsia y se ha determinado que su participación es decisiva en la fisiopatología de esta enfermedad. La participación del sistema inmunológico en la fisiopatología de la preeclampsia alcanza un alto nivel de complejidad pues interacciona con otros sistemas (coagulación, renal, cardiovascular y endocrinológico entre otros) favoreciendo así la enfermedad. Es por esto que el tratamiento debe ser integral, con una visión holística del padecimiento y que requiere de un equipo multidisciplinario, que actué armónicamente para así alcanzar el mayor éxito terapéutico con la menor frecuencia de secuelas para el binomio madre-feto o madre-recién nacido. En la gestación se desarrolla la denominada "tolerancia inmunológica del embarazo", en ese estado de tolerancia inmunológica las células B y T pueden reconocer antígenos específicos (por ejemplo, los paternos) y posteriormente activarse y generar la respuesta inmunológica, por lo que la preeclampsia podría ser considerada como una patología autoinmune, donde la perdida de la tolerancia inmunológica sería la piedra angular en la fisiopatología, conocer como limitar o regular esta activación celular anómala podría servir para proponer nuevos acercamientos terapéuticos y controlar así esta enfermedad.

Abstract Preeclampsia is a pathology with high morbidity and mortality worldwide. In this disease, the placenta is an organ of shock where inflammation and the immune response generate the damage that results in the characteristic clinical scenario. The classic triad in preeclampsia is made up of hypertension, edema, and proteinuria, so it is thought that the endothelium must be affected by inflammatory-immunological activity. The immune system acts in the development of pregnancy and does so at different times and regulating physiologically. Both, cellular and humoral components of the innate and acquired response have been studied in patients with preeclampsia and it has been determined that their participation is decisive in the pathophysiology of this disease. The involvement of the immune system in the pathophysiology of preeclampsia reaches a high level of complexity since it interacts with other systems (coagulation, renal, cardiovascular and endocrinological among others) thus favoring the disease. For this reason, treatment must be comprehensive, with a holistic vision of the condition and requires a multidisciplinary team that acts harmoniously to achieve the greatest therapeutic success with the least frequency of sequelae for the mother-fetus or mother-newborn dyads. During pregnancy, the so-called "immunological tolerance of pregnancy" develops, in this state of immunological tolerance the B and T cells can recognize specific antigens (for example, the paternal ones) and later activate and generate the immune response, which is why preeclampsia could being considered an autoimmune pathology, where the loss of immunological tolerance would be the cornerstone of pathophysiology, knowing how to limit or regulate this abnormal cell activation could help to propose new therapeutic approaches and thus control this disease.

ARE CALCIUM SILICATE SEALERS LESS CYTOTOXIC AND GENOTOXIC THAN EPOXY RESIN SEALERS? A SYSTEMATIC REVIEW OF IN VITRO STUDIES

Aims: This systematic review aimed to evaluate whether calcium silicate-based sealers are less cytotoxicity and genotoxicity than epoxy resin-based sealers. Materials and Methods: Systematic searches were conducted for studies published up to September 27th, 2022, without restriction for language or year of publication, in the following databases: MEDLINE/PubMed, Scopus, Web of Science and Grey Literature Report. Only in vitrostudies that evaluated the cytotoxicity or genotoxicity of calcium silicate and epoxy resin-based sealers were included. The quality assessment was performed. Results: After duplicate removal and eligibility criteria assessment, a total of thirty-four studies were included. Twenty-eight studies had a low risk of bias, and six studies had amoderate risk of bias. In general, calcium silicate-based sealers had a lower cytotoxic and genotoxic potential than epoxy-resin based sealers.Conclusions: Based on the findings from in vitrostudies, calcium silicate-based sealers are less cytotoxic andgenotoxic than epoxy resin-based sealers

Hydroxyanthracene derivates citotoxicity: A differential evaluation between single molecule and whole plant extract.

Hydroxyanthracene derivates (HADs) are a group of natural or synthetic compounds with a wide range of biological activities (for instance, anti-inflammatory, antibacterial, and antiarthritic). In addition, because of their properties for helping the normal bowel function, HADs are widely used in constipation as pharmacological drugs and nutritional supplements. Nevertheless, during the past years, a safety usage of HAD products has been under consideration because some studies reported that HADs are not lacking toxicity (i.e., genotoxic and carcinogenic activity). Thus, the first objective of this study is to shed light on the large variability in composition of botanical food supplements containing HAD by a systematic analysis of the qualitative and quantitative composition of a cohort of extracts and raw materials of plants with high levels of anthraquinones commercially available (Cassia angustifolia, Rhamnus purshiana, Rhamnus frangula, Rheum palmatum, and Rheum raponticum). To date, the investigation of HAD toxicity was based on in vitro and in vivo studies conducted mainly on the use of the single molecules (emodin, aloe-emodin, and rhein) rather than on the whole plant extract. The qualitative-quantitative characterization was the starting point to select the most appropriate products to be used as treatment for our in vitro cell studies. Thus, the second objective of this study is the investigation, for the first time, of the toxic events of HAD used as single molecule in comparison with the whole plant extracts containing HAD in an intestinal in vitro model using human colorectal adenocarcinoma cells (Caco-2). In addition, a shotgun proteomics approach was applied to profile the differential protein expression in the Caco-2 cells after a single-HAD or whole-plant extract treatment to fully understand the potential targets and signaling pathways. In conclusion, the combination of a detailed phytochemical characterization of HAD products and a largely accurate analysis of the proteomic profile of intestinal cells treated with HAD products provided the opportunity to investigate their effects in the intestinal system.

Pterostilbene fluorescent probes as potential tools for targeting neurodegeneration in biological applications.

Several epidemiological studies suggest that a diet rich in fruit and vegetables reduces the incidence of neurodegenerative diseases. Resveratrol (Res) and its dimethylated metabolite, pterostibene (Ptb), have been largely studied for their neuroprotective action. The clinical use of Res is limited because of its rapid metabolism and its poor bioavailability. Ptb with two methoxy groups and one hydroxyl group has a good membrane permeability, metabolic stability and higher in vivo bioavailability in comparison with Res. The metabolism and pharmacokinetics of Ptb are still sparse, probably due to the lack of tools that allow following the Ptb destiny both in living cells and in vivo. In this contest, we propose two Ptb fluorescent derivatives where Ptb has been functionalised by benzofurazan and rhodamine-B-isothiocyanate, compounds 1 and 2, respectively. Here, we report the synthesis, the optical and structural characterisation of 1 and 2, and, their putative cytotoxicity in two different cell lines.

Cytotoxicity of cinchona alkaloid organocatalysts against MES-SA and MES-SA/Dx5 multidrug-resistant uterine sarcoma cell lines.

Since the first application of natural quinine as an anti-malarial drug, cinchona alkaloids and their derivatives have been exhaustively studied for their biological activity. In our work, we tested 13 cinchona alkaloid organocatalysts, synthesised from quinine. These derivatives were screened against MES-SA and Dx5 uterine sarcoma cell lines for in vitro anticancer activity and to investigate their potential to overcome P-glycoprotein (P-gp) mediated multidrug resistance (MDR). Decorating quinine with hydrogen-bond donor units, such as thiourea and (thio)squaramide, resulted in decreased half-maximal growth inhibition values on both cell lines (1.3-21 µM) compared to quinine and other cinchona alcohols (47-111 µM). Further cytotoxicity studies conducted in the presence of the P-gp inhibitor tariquidar indicated that several analogues, especially cinchona amines and squaramides, but not thiosquaramide, were expelled from MDR cells by P-gp. Similarly to the established P-gp inhibitor quinine, 6 cinchona analogues were shown to inhibit calcein-AM efflux. Interestingly, quinine and didehydroquinine exhibited a marginally increased toxicity against the multidrug resistant Dx5 cells. Collateral sensitivity of the MDR cell line was more pronounced when the cinchona thiosquaramide was complexed with Cu(II) acetate. Based on the results, cinchona derivatives are good anticancer candidates for further drug development.

Biofilm formation and cell viability on monolithic zirconia with silver-doped sodalime glass.

The present study evaluated the effect of glass application with and without silver-doped soda-lime glass on roughness, biofilm formation, cell viability and flexural strength of a zirconia. Samples of 3-YTZP (3 mol% yttria stabilized tetragonal zirconia polycrystals) were divided into: polished (P); glaze (G); glass infiltration (INF); 4% silver-doped soda-lime glass (Ag4); glass infiltration + 4% silver-doped soda-lime glass (INF-Ag4); 5% silver-doped soda-lime glass (Ag5); glass infiltration + 5% silver-doped soda-lime glass (INF-Ag5). Samples were submitted to the following analyses: roughness (Ra); free surface energy (FSE); colony-forming units count (log CFU/mL); scanning electron microscopy (SEM); cytotoxicity (MTT assay) and flexural strength. Ag5 had greater roughness and FSE, but less biofilm adherence. In the CFU, silver-doped soda-lime glass groups inhibited the growth of Candida albicans, while the Ag5 inhibited Streptococcus mutans and none of the groups was effective against Streptococcus sanguinis. In the qualitative evaluation, lower number of colonies in the Ag5 grew up, compared to the control groups (P; G and INF) for both C. albicans and S. mutans. Regarding the MTT assay, the Ag4, INF-Ag4 and INF-Ag5 obtained percentage of cell viability greater than 50%. Ag5 showed lower flexural strength when compared to the control groups, while the application of glass infiltration increased the flexural strength by formation of a graded region between zirconia-glass. In conclusion, Ag5 had the greatest antimicrobial effect, Ag4 and INF-Ag4 were the less cytotoxic and the INF was the most resistant to fracture. Therefore, INF-Ag4 conciliates the best performance in terms of antimicrobial and mechanical properties for a 3-YTZP.

Thermo-mechanical, antimicrobial and biocompatible properties of PVC blends based on imidazolium ionic liquids.

The aim of this study was the development of antimicrobial polyvinylchloride (PVC) blends loaded with 0.1-10% (w/w) of the ILs 1-hexadecyl-3-methylimidazolium 1,3-dimethyl 5-sulfoisophthalate (HdmimDMSIP) and 1-octyloximethyl-3-methylimidazolium hexafluorophosphate (OOMmimPF6). The synthetized ILs were characterized by 1HNMR, MALDI-TOF, DSC and TGA. PVC/ILs films were obtained by solvent casting.Thermal and mechanical properties (tensile stress TS and elongation at break EB), morphology by SEM, surface wettability, antimicrobial activity, cytotoxicity and ILs release in sterile water from PVC/ILs film blends were determined. Results demonstrated that the presence of both ILs in PVC formulation slightly affected thermal and mechanical properties of blends. The loading of both ILs into PVC matrix made PVC/ILs films hydrophilic, especially at the highest concentration of HdmimDMSIP. The PVC/ILs blends displayed antibacterial activity up to ILs lowest concentrations (0.1-0.5%). The inhibition of Escherichia coli growth was lower than that showed toward Staphylococcus epidermidis. The addition of 10% ILs concentration resulted excessive as demonstrated by accumulation of ILs on film surfaces (SEM) and ILs high release from PVC/ILs blends during the first day of water immersion. Biocompatibility studies highlighted that the addition of low amounts of both ILs into PVC matrix is not cytotoxic for mouse fibroblast cells (L929), supporting their potential use for biomedical porposes.

Negative impact of high body mass index on cetuximab-mediated cellular cytotoxicity against human colon carcinoma cells.

This study assessed the relationship between the ability of Natural Killer (NK) cells to activate antibody-dependent cellular cytotoxicity against human HT29 colorectal cancer cells exposed to cetuximab and the body mass index of the human subjects from whom the NK cells had been obtained. NK cells obtained from 73 human donors were co-incubated with HT-29 human colon cancer cells in the presence or absence of cetuximab. Antibody-dependent cellular cytotoxicity was assessed by measuring LDH release. A significant negative correlation was observed between body mass index and cetuximab-induced antibody-dependent cellular cytotoxicity. NK cells obtained from subjects who were overweight or with obesity were less efficient in killing cetuximab-treated HT29 cells than those derived from normal weight donors. Our results suggest that the success of cetuximab-containing regimens might be impaired in overweight and obese patients with colorectal cancer.

Effect of silver nanoparticles (AgNPs) exposure on microRNA expression and global DNA methylation in endothelial cells EA.hy926.

The aim of this study was to determine the effect of AgNPs on the epigenome of endothelial cells EA.hy926, including the levels of expression of microRNAs (miRNAs) and global DNA methylation patterns. In addition, evaluation of the expression of inflammatory genes and the levels of VCAM-1 protein (miRNA-126 target) was performed. The expression levels of analyzed miRNAs (microRNAs-126, 155 and 146) were reduced significantly and there were not observed changes in inflammatory gene expression. Regarding the levels of protein vascular cell adhesion molecule 1 (VCAM-1), they increase significantly to 0.5 µM AgNPs at 24 h of exposure. As far as DNA methylation is concerned, we found that AgNPs induce a state of global hyper-methylation. In conclusion, it was demonstrated that direct contact between AgNPs and endothelial cells resulted in the dysregulation of highly enriched and vastly functional miRNAs and DNA hypermethylation, that may have multiple effects on endothelium function and integrity.

A new Ag-nanostructured hydroxyapatite porous scaffold: Antibacterial effect and cytotoxicity study.

We report a new chemical method for the functionalization of Mg-hydroxyapatite (Mg-HA) scaffold with Ag nanoparticles (Ag NPs) integrating in one step both the synthesis of the Ag NPs and their nano-structuring into the HA matrix (Ag-Mg-HA scaffold). This method exploits a green photochemical synthesis and allows the direct growth of Ag NPs on the Mg-HA surface. The surface structure of Ag-Mg-HA scaffold, investigated by scanning electron microscopy, shows no significant changes in the morphology upon Ag NPs incorporation. The presence of Ag was confirmed by EDX analysis. TEM and spectroscopic investigations show Ag NPs spherical shaped with a mean diameter of about 20 nm exhibiting the typical plasmon absorption band with maximum at 420 nm. The antibacterial properties of Ag-Mg-HA scaffolds were tested against two bacterial strains, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The results show excellent antibacterial properties achieving up to 99% and 100% reduction of colonies for both bacteria cultures after 24 h of incubation and 100% of reduction after 48 h of incubation. The cytotoxicity of Ag-Mg-HA was also in deep investigated assessing both cell proliferation and differentiation using hADSCs (human Adipose Derived Stem Cells) and testing data point at 0, 7, 14 and 24 days. The results show cytotoxic effect with cell proliferation decreasing up to 90% at 24 days and osteogenic differentiation inhibition. The observed cytotoxicity can be probable ascribed to the oxidative stress by ROS. Indeed, considering the effectiveness of the nanofunctionalization method and the excellent antibacterial properties showed by the Ag-Mg-HA scaffold, future works will be devoted to create nanofunctionalized scaffold satisfying both antimicrobial and osteo-regenerative properties.

Cyto-genotoxic evaluation of novel anti-tubercular copper (II) complexes containing isoniazid-based ligands.

Considering the promising previous results of Cu (II) complexes with isoniazid active ligand against Mycobacterium tuberculosis, the main causative agent of tuberculosis, novel biological assays evaluating its toxicogenic potential were performed to ensure the safe use. The genotoxicity/mutagenicity of the complexes CuCl2(INH)2.H2O (I1), Cu(NCS)2(INH)2.5H2O (I2) and Cu(NCO)2(INH)2.4H2O (I3) was evaluated by the Comet, Micronucleus-cytome and Salmonella microsome (Ames test) assays. The cell viability using resazurin assay indicated that I1, I2 e I3 had moderate to low capacity to reduce the viability of colorectal cells (Caco-2), liver cells (HepG2), lung cells (GM 07492-A and A549) and endothelial cells (HU-VE-C). On genotoxicity/mutagenicity, I1 complex did not induce sizable levels of DNA damage in HepG2 cells (Comet assay), and gene (Ames test) and chromosomal (Micronucleus-cytome assay) mutations. Already, I2 and I3 complexes were considered mutagenic in the highest concentrations used. In light of the above, these results contribute to valuable data on the safe use of Cu(II) complexes. Considering the absence of mutagenicity and cytotoxicity of I1, this complex is a potential candidate for the development of a new drug to the treatment tuberculosis, while I2 and I3 require caution in its use.

Compostos carbonílicos α, ß-insaturados e hidrazonas sintéticas como antiparasitários / α, ß-Unsaturated carbonyl compounds and Synthetic hydrazones as antiparasitics

Apesar da grande relevância médica e social, e por serem responsáveis por grande parte das mortes em países subdesenvolvidos e em desenvolvimento as doenças negligenciadas (DN), ainda, não apresentam terapêutica eficaz. Dentre as diversas DN, doenças como a doença de Chagas, a Leishmaniose visceral e a malária, se destacam no cenário nacional, por terem alta incidência e prejuízos sociais. Os fármacos disponíveis para o tratamento destas parasitoses, apresentam alta toxicidade e, em alguns casos, resistência por parte dos parasitas. Assim sendo, faz-se necessário o planejamento e desenvolvimento de novos agentes quimioterápicos mais seguros e eficazes. Dentre as diferentes estratégias de planejamento de fármacos, selecionamos o planejamento de fármacos baseado na estrutura do ligante - LBDD (Ligand-Based Drug Design) - como base para desenvolvimento deste trabalho. Nesta estratégia, utiliza-se o conhecimento de moléculas (ligantes) e de suas atividades biológicas conhecidas previamente determinadas experimentalmente, como protótipos para a busca de novas entidades químicas com atividade biológica semelhante ou melhorada. Sendo assim, o presente trabalho teve como objetivo a síntese e avaliação biológica de moléculas bioativas para o tratamento de doenças parasitárias. Baseando-se no conhecimento prévio da atividade antiparasitária de compostos carbonílicos α,ß-insaturados e hidrazonas, foram sintetizados séries de compostos destas classes químicas na busca de novos agentes quimioterápicos. Os compostos obtidos foram avaliados contra a forma epimastigota de Trypanosoma cruzi, promastigota de Leishmania donovani, amastigota de Leishmania infantum e, também, determinou-se o seu grau de citotoxicidade (CC50) frente a células de macrófago humanos diferenciado (THP-1). As 31 moléculas obtidas foram caracterizadas por técnicas de ponto de fusão, RMN 1H e RMN 13C e avaliada sua pureza por HPLC. Os compostos da classe da cinamoil-hidrazonas apresentaram-se como promissores antiparasitários, mostrando atividade frente a forma promastigota (Leishmania donovani), 4 dos 12 compostos foram ativos (IC50= 1,27 - 13,68 µM) e frente a forma amastigota (Leishmania infantum), 10 dos 12 compostos apresentaram atividade (9,09 - 63,5 µM). Mesmo apresentando citotoxicidade moderada (CC50 = 8,83 - 87,47 µM), os compostos obtiveram valores inferiores ao fármaco de referência (doxorubicina: CC50 = 0,26 µM). Diante do exposto, o planejamento de fármacos realizado por LBDD mostrou-se bem-sucedido, pois a classe de cinamoil-hidrazonas mostrou-se promissora como antiparasitários, visto sua atividade na escala de baixo micromolar e moderada citotoxicidade em células humanas. Esses resultados assinalam que a classe de compostos descrita está passível a continuar sendo investigada no intuito de aprimorar os protótipos obtidos na busca de novos agentes quimioterápicos antiparasitários e desvendar os mecanismos de ação leishmanicida

Despite to the great medical and social relevance and the amount of deaths in underdeveloped and developing countries, neglected diseases (ND) still do not have an effective therapy. Among the various ND, illnesses such as Chagas disease, visceral leishmaniasis and malaria holds a great importance in the Brazilian scenario due to high incidence and social damage. The drugs available for the treatment of these parasitosis present high toxicity and, in some cases, resistance by the pathogens. Thus, the planning and development of new, safer and more effective chemotherapeutic substances are urgent needed. Among the different drug planning strategies, we selected ligand-based drug design (LBDD) as the basis for the development of this work. In this strategy, we use the knowledge of molecules (ligands) and their known biological activities previously determined experimentally, as prototypes to search for new chemical entities with similar or improved biological activity. Therefore, the present work aimed the synthesis and biological evaluation of bioactive molecules for the treatment of parasitic diseases. Based on previous knowledge of the antiparasitic activity of α,ß-unsaturated and hydrazone carbonyl compounds, series of compounds of these chemical classes were synthesized in search of new chemotherapeutic agents. The compounds obtained were evaluated against the epimastigote form of Trypanosoma cruzi, Leishmania donovani promastigote, Leishmania infantum amastigote and their cytotoxicity (CC50) against differentiated human macrophages (THP-1). The 31 molecules obtained were characterized by melting point, 1 H NMR and 13C NMR techniques and their purity were characterized by HPLC. The cinnamoyl hydrazone class compounds showed promising antiparasitic activity, showing activity against promastigote form (L. donovani), 4 of 12 compounds were active (IC50 = 1.27 - 13.68 µM) and amastigote form (L. infantum), 10 of the 12 compounds showed activity (9.09 - 63.5 µM). Even presenting moderate cytotoxicity (CC50 = 8.83 - 87.47 µM), the compounds had values below the reference drug (doxorubicin: CC50 = 0.26 µM). Considering the results, LBDD drug planning proved to be successful and the class of cinnamoyl hydrazones were promising as antiparasitics due to its activity in low micromolar scale and moderate cytotoxicity in human cells. These results indicate that the described class of compounds can be further investigated in order to improve the prototypes obtained in the search for new antiparasitic chemotherapeutic agents and to unravel the mechanisms of action of leishmanicidal molecules

Synthesis of silver nanoparticles using a Mentha spicata extract and evaluation of its anticancer and cytotoxic activity.

In this study, silver nanoparticles (NP) were synthesized by two methods: using an aqueous extract of Mentha spicata leaves and using citrate ions as stabilizing agent, and the cytotoxicity and anticancer activity of both NP were evaluated in vitro. The particles synthesized with the aqueous extract were spherical with a size ranging from 15 to 45 nm. These NP decreased cell viability in all of the cells studied; however, the IC50 could only be estimated in the Chang liver cells (IC50 = 21.37 µg/mL). These particles also decreased the generation of reactive oxygen species in Chang and SiHa cells. Additionally, the dispersions decreased the activity of caspase-3. There was no significant difference between the biological activities of the NP obtained with the aqueous extract and the NP synthesized using citrate ions. This study showed that an aqueous extract of M. spicata is an excellent alternative for the synthesis of silver NP. These NP showed cytotoxicity and anticancer activity in vitro. Although more experiments are required, the cell death occurs probably through a mechanism different from apoptosis.

Preservation of cytotoxic granule production in response to mycobacterial antigens by T-lymphocytes from vertically HIV-infected Brazilian youth on effective combined antiretroviral therapy.

BACKGROUND: HIV infection harms adaptive cellular immunity mechanisms. Long-term virological control by combined antiretroviral therapy (cART) reduces the risk of mycobacterial infections. Thus, we aimed to study cellular responses to mycobacterial antigens in 20 HIV-infected adolescents with at least one year of virological control (HIV-RNA <40 copies/mL) and 20 healthy adolescents. METHODS: We evaluated CD8 and γδ T-cell degranulation by measurement of CD107a membrane expression after stimulation with lysates from BCG (10 µg/mL) and H37RA Mycobacterium tuberculosis (Mtb, 10 µg/mL). Immune activation and antigen-presenting ability were also assessed by determination of HLA-DR, CD80, and CD86 markers. RESULTS: TCR γδ T-cell CD107a expression was similar between groups in response to mycobacterial antigens, and lower in the HIV-infected group in response to mitogen. Higher baseline HLA-DR expression and lower mycobacterial-stimulated expression was found within the HIV-infected group. CONCLUSIONS: Similar degranulation in stimulated CD8+ and TCR γδ T-cells from HIV-infected adolescents, when compared to healthy controls suggests long-term immunological preservation with immune reconstitution under successful cART. However, differences in HLA-DR expression may represent ongoing inflammation and lower specific responses in HIV-infected youth. These features may be relevant in the context of the precocity and severity of vertically acquired HIV infection.

Semisynthetic eugenol derivatives as antifungal agents against dermatophytes of the genus Trichophyton.

PURPOSE: Eugenol, the main component of clove bud essential oil (Eugenia caryophyllus), has been linked to antimicrobial, anti-inflammatory, insecticidal and immunomodulatory properties. The purpose of this study was to evaluate the antifungal and cytotoxic activity of eugenol, the essential oil of Eugenia caryophyllus, and some semisynthetic derivatives of eugenol against dermatophytes of the genus Trichophyton. METHODOLOGY: We evaluated the antifungal effect of the compounds, determining the minimum inhibitory concentrations (MICs) by the microdilution method and the minimum fungicidal concentrations by cultures from the inhibitions. Additionally, the inhibition of the radial growth of the mycelium of the dermatophyte fungi was tested by poisoned substrate. Cytotoxicity was measured by the colorimetric method on Vero cells. RESULTS: All of the eugenol compounds tested exhibited antifungal properties, showing MICs of 62.5-500 µg ml-1 , determined within three dermatophyte species: Trichophyton rubrum, Trichophyton mentagrophytes and Trichophyton tonsurans. Among these derivatives, methyl isoeugenol, at concentrations of 300 and 100 µg ml-1, was found to completely inhibit (100 %) radial growth of the mycelium of all three species after 20 days of treatment. Additionally, phenotypic variations related to the decrease in pigment production of T. rubrum were observed after treatment with O-ethyl and O-butyl isoeugenol derivatives. Meanwhile, all of the tested (iso)eugenol molecules exhibited moderate toxicity in Vero cells [50 % cytotoxic concentration (the concentration required for a 50 % reduction in cell viability; CC50): 54.06-265.18 µg ml-1 ). CONCLUSION: The results suggest that the semisynthetic eugenol derivatives (SEDs) show promising antifungal activity and selectivity against dermatophyte fungi.

Preservation of cytotoxic granule production in response to mycobacterial antigens by T-lymphocytes from vertically HIV-infected Brazilian youth on effective combined antiretroviral therapy

ABSTRACT Background: HIV infection harms adaptive cellular immunity mechanisms. Long-term virological control by combined antiretroviral therapy (cART) reduces the risk of mycobacterial infections. Thus, we aimed to study cellular responses to mycobacterial antigens in 20 HIV-infected adolescents with at least one year of virological control (HIV-RNA <40 copies/mL) and 20 healthy adolescents. Methods: We evaluated CD8 and γδ T-cell degranulation by measurement of CD107a membrane expression after stimulation with lysates from BCG (10 µg/mL) and H37RA Mycobacterium tuberculosis (Mtb, 10 µg/mL). Immune activation and antigen-presenting ability were also assessed by determination of HLA-DR, CD80, and CD86 markers. Results: TCR γδ T-cell CD107a expression was similar between groups in response to mycobacterial antigens, and lower in the HIV-infected group in response to mitogen. Higher baseline HLA-DR expression and lower mycobacterial-stimulated expression was found within the HIV-infected group. Conclusions: Similar degranulation in stimulated CD8+ and TCR γδ T-cells from HIV-infected adolescents, when compared to healthy controls suggests long-term immunological preservation with immune reconstitution under successful cART. However, differences in HLA-DR expression may represent ongoing inflammation and lower specific responses in HIV-infected youth. These features may be relevant in the context of the precocity and severity of vertically acquired HIV infection.

A green approach for alginate extraction from Sargassum muticum brown seaweed using ultrasound-assisted technique.

Ultrasound assisted aqueous extraction of alginate from Sargassum muticum was proposed to minimize the use of chemicals, high temperatures and prolonged times, with comparable extraction yields to conventional acid/alkali procedures. The alginate, precipitated from the liquors obtained after ultrasound assisted extraction of fucoidan and phlorotannin fractions, and converted to alginic acid sodium salt by a green treatment was characterized by FTIR-ATR, 1H NMR, HPSEC, MALDI-TOF, rheology and citotoxitity. A clear influence of the sonication time was observed on the alginate molar mass, block structure, thermo-rheological and tumoral cell growth inhibition features. All tested hydrogels featured stable and thermo-reversible characteristics.

Physicochemical characterization and evaluation of in vitro and in vivo toxicity of goldenberry extract nanoemulsion / Caracterização físico-química e avaliação da toxicidade in vitro e in vivo de nanoemulsão contendo extrato de goldenberry

ABSTRACT: Oil-in-water (O/W) nanoemulsion containing goldenberry extract was elaborated using a high-energy ultrasonic bath method. Physicochemical characterization of the formulation was carried out by determining pH, mean droplet diameter, polydispersity index (PDI) and zeta potential. Nanoemulsion toxicity was assessed using in vitro assays with tumor and non-tumor cell lines, and in vivo using Caenorhabditis elegans. The pH of the nanoemulsion was 3.84, the mean droplet diameter was 268 ± 7 nm, PDI 0.113 and zeta potential -13.94 mV. Results of the cytotoxicity assays employing non-tumor cells indicated that the extract associated or not with nanoemulsion maintained cell viability at different concentrations tested. In the assays using tumor lineage, it is observed that the nanoemulsion containing the extract had higher antitumor activity than the free extract. As for the in vivo tests, there was no change in the survival rate of the worms.

RESUMO: Nanoemulsão óleo/água (O/A) contendo extrato de goldenberry foi elaborada utilizando método de banho ultrassônico de alta energia. A caracterização físico-química da formulação foi realizada pela determinação do pH, diâmetro médio de gotas, índice de polidispersão (PDI) e potencial zeta. A toxicidade das nanoemulsões foi avaliada utilizando ensaios in vitro com linhas celulares tumorais e não tumorais e in vivo utilizando Caenorhabditis elegans. O pH da nanoemulsão foi de 3,84, o diâmetro médio das gotículas foi de 268 ± 7 nm, PDI 0,113 e o potencial zeta -13,94 mV. Os resultados dos ensaios de citotoxicidade empregando células não tumorais indicaram que o extrato associado ou não à nanoemulsão manteve a viabilidade celular em diferentes concentrações testadas. Nos ensaios, utilizando linhagem tumoral, observou-se que a nanoemulsão contendo o extrato apresentou maior atividade antitumoral do que o extrato livre. Quanto aos testes in vivo, não houve mudança na taxa de sobrevivência dos vermes.