Sodium valproate affects the expression of p16INK4a and p21WAFI/Cip1 cyclin­dependent kinase inhibitors in HeLa cells.

p16INK4a and p21WAF1/Cip1 are cyclin-dependent kinase inhibitors involved in cell cycle control, which can function as oncogenes or tumor suppressors, depending on the context of various extracellular and intracellular signals, and cell type. In human papillomavirus-induced cervical cancer, p16 INK4a shows oncogenic activity and functions as a diagnostic marker of cervical neoplasia, whereas p21 WAF1/Cip1 acts as a tumor suppressor and its downregulation is associated with the progression of malignant transformation. Several histone deacetylase (HDAC) inhibitors promote the positive and negative regulation of a number of genes, including p16 INK4a and p21 WAF1/Cip1; however, the effects of sodium valproate (VPA) on these genes and on the proteins they encode remain uncertain in HeLa cervical cancer cells. In the present study, these effects were investigated in HeLa cells treated with 0.5 or 2 mM VPA for 24 h, using reverse transcription-quantitative PCR, confocal microscopy and western blotting. The results revealed a decrease in the mRNA expression levels of p16 INK4a and a tendency for p16INK4a protein abundance to decrease in the presence of 2 mM VPA. By contrast, an increase in the protein expression levels of p21WAF1/Cip1 was detected in the presence of 0.5 and 2 mM VPA. Furthermore, VPA was confirmed to inhibit HDAC activity and induce global hyperacetylation of histone H3. Notably, VPA was shown to suppress p16 INK4a, a biomarker gene of cervical carcinoma, and to increase the abundance of the tumor suppressor protein p21WAF1/Cip1, thus contributing to the basic knowledge regarding the antitumorigenic potential of VPA. Exploration of epigenetic changes associated with the promoters of p16 INK4a and p21 WAF1/Cip1, such as histone H3 methylation, may provide further information and improve the understanding of these findings.

A fluorescent glyconanoprobe based on quantum dots and thiolated glucose: Applications in monolayers and spheroids of cancer cells.

The differential energy metabolism of cancer cells has stimulated the development of tools that can be applied to better understand the complex biological interaction involved in the uptake of glucose analogs at the cellular level in this disease. Herein, we explored the outstanding optical properties of quantum dots (QDs) to develop a new fluorescent glyconanoprobe using the 1-thio-ß-d-glucose (Glc). Then, monolayers and spheroids of HeLa cells were applied to probe the biological interaction with the conjugate through fluorescence techniques. Spheroids have been gaining prominence for better mimicking the tumor microenvironment. The Glc-QDs conjugate was prepared by a facile and direct procedure based on the affinity of the Glc thiol group by the QD semiconductor surface. The conjugation was evaluated and confirmed by Zeta potential (ζ) measurements, FTIR spectroscopy, and fluorescence correlation spectroscopy (FCS). Moreover, a biological assay using Candida albicans yeasts coated with concanavalin A, by exploring the lectin-carbohydrate affinity, was also developed to further confirm the conjugation, which corroborated the previous analyses. The hanging drop method was used to prepare the spheroids. The fluorescence microscopy analyses indicated an intracellular labeling by the glyconanoprobe, in both cell culture models. Flow cytometry assays revealed effective uptake of the conjugate (above ca. 76%), even by cells cultivated as spheroids, applying short incubation time. Therefore, a new fluorescent glyconanoprobe was developed, which showed potential to be applied for investigating mechanisms involved in the uptake of glucose analogs, both by simpler and complex cancer biological models, as monolayers and spheroids.

Polycaprolactone nanofibers colonized by HeLa cells: an alternative for in vitro investigation of fungal infection.

Introduction: In vitro 3D equivalent tissues can be used for studies of fungal infections. Objectives: To develop 3D electrospun nanofibers using polycaprolactone (PCL) colonized by HeLa cells as a possible in vitro model for the investigation of fungal infection. Materials & methods: A PCL solution was synthesized and electrospun. HeLa cells were cultured on the nanostructured PCL scaffolds, forming a 3D structure. Physicochemical, biological and Candida albicans infection assays were performed in this model. Results: The nanostructured PCL scaffolds showed favorable physicochemical characteristics and allowed the colonization of HeLa cells, which showed indications of extracellular matrix production. Conclusions: Fungal infection was evidenced in the 3D nanostructured PCL scaffolds, being viable, economical and compatible to study fungal infections in vitro.

Quantitative Proteomics for the Identification of Differentially Expressed Proteins in the Extracellular Vesicles of Cervical Cancer Cells.

The extracellular vesicles (EVs) in a tumoral microenvironment can exert different functions by transferring their content, which has been poorly described in cervical cancer. Here, we tried to clarify the proteomic content of these EVs, comparing those derived from cancerous HPV (+) keratinocytes (HeLa) versus those derived from normal HPV (-) keratinocytes (HaCaT). We performed a quantitative proteomic analysis, using LC-MS/MS, of the EVs from HeLa and HaCaT cell lines. The up- and downregulated proteins in the EVs from the HeLa cell line were established, along with the cellular component, molecular function, biological processes, and signaling pathways in which they participate. The biological processes with the highest number of upregulated proteins are cell adhesion, proteolysis, lipid metabolic process, and immune system processes. Interestingly, three of the top five signaling pathways with more up- and downregulated proteins are part of the immune response. Due to their content, we can infer that EVs can have a significant role in migration, invasion, metastasis, and the activation or suppression of immune system cells in cancer.

REST/NRSF Silencing Modifies Neuronal Gene Expression in siRNA-Treated HeLa Cells: A Preliminary Exploration in the Search for Neuronal Biomarkers of Cervical Cancer.

Background and Objectives: REST (RE1-silencing transcription factor) diminution is associated with transcriptional relaxation, neuropeptide overexpression, and phenotype redefinition in neuroendocrine cancers, but this effect has barely been studied in cervical cancer (CC). We previously reported reduced expressions of REST in samples with premalignant lesions and CC; however, the transcriptional consequences for neural genes associated with reduced REST expression in CC are unknown. Therefore, the objective of this work was to evaluate the expression of neuronal genes in cancerous cells with reduced expression levels of REST. Materials and Methods: Here, we monitored levels of REST by immunostaining along the premalignant lesions and in invasive cervical squamous cell carcinoma (SCC) and endocervical adenocarcinoma (ADC) in tissue samples from female patients from southern Mexico and the derivative cell lines SiHa and HeLa, respectively. Next, we selected REST target genes in silico and explored the effect of REST silencing by RT-PCR in siRNA-treated HeLa cells. Results: The results show a REST diminution in premalignant lesions, SCC, ADC, and cancerous cell lines. Further REST silencing in HeLa cells altered the expression of genes containing the RE1 (Restrictive Element 1) sequence, including CgA (chromogranin A), CHRNß2 (cholinergic receptor nicotinic ß 2 subunit), BDNF (brain-derived neurotrophic factor), CRF (corticotropin-releasing factor), and RASSF1A (Ras association domain family 1). Conclusions: This work provides preliminary evidence of the role of REST loss in the transcriptional regulation of its target genes in HeLa cells, which could have positive implications for the search for new biomarkers of cervical cancer.

Effect of Electrospun PLGA/Collagen Scaffolds on Cell Adhesion, Viability, and Collagen Release: Potential Applications in Tissue Engineering.

The development of scaffolding obtained by electrospinning is widely used in tissue engineering due to porous and fibrous structures that can mimic the extracellular matrix. In this study, poly (lactic-co-glycolic acid) (PLGA)/collagen fibers were fabricated by electrospinning method and then evaluated in the cell adhesion and viability of human cervical carcinoma HeLa and NIH-3T3 fibroblast for potential application in tissue regeneration. Additionally, collagen release was assessed in NIH-3T3 fibroblasts. The fibrillar morphology of PLGA/collagen fibers was verified by scanning electron microscopy. The fiber diameter decreased in the fibers (PLGA/collagen) up to 0.6 µm. FT-IR spectroscopy and thermal analysis confirmed that both the electrospinning process and the blend with PLGA give structural stability to collagen. Incorporating collagen in the PLGA matrix promotes an increase in the material's rigidity, showing an increase in the elastic modulus (38%) and tensile strength (70%) compared to pure PLGA. PLGA and PLGA/collagen fibers were found to provide a suitable environment for the adhesion and growth of HeLa and NIH-3T3 cell lines as well as stimulate collagen release. We conclude that these scaffolds could be very effective as biocompatible materials for extracellular matrix regeneration, suggesting their potential applications in tissue bioengineering.

[Antiproliferative, apoptotic, and antimigratory activities of kafirins on cervical cancer-derived cell lines]. / Actividades antiproliferativas, apoptóticas y antimigratorias de las kafirinas en líneas celulares derivadas de cáncer cervical.

Background: Cervical cancer is one of the leading causes of death in women worldwide, both in developed and developing countries. Therefore, effective treatment of cervical cancer with potential anti-tumor drugs is important. However, new treatments inspired by nutritional medicine are needed. Objective: To use the human cervical cancer cell lines HeLa and SiHa to evaluate the antiproliferative, apoptotic, and migratory activity of sorghum (kafirins). Materials and methods: The anticancer effects of the kafirins were examined by counting cells, MTT assays, apoptosis, and migration assays. Results: This investigation showed that sorghum induced growth inhibition of HeLa and SiHa cells at a significant level. The growth inhibition is dose-dependent and irreversible. When HeLa and SiHa cells were treated with sorghum due to the activity of kafirins, morphological changes were observed, which were identified through the formation of apoptopic bodies. And the kafirins at concentrations of 37.5, 75, 150, and 300 µg/mL decreased the migration of HeLa cells and SiHa cells. Conclusion: This paper demonstrates the induction of antiproliferative, apoptotic, and anti-migratory activity in HeLa and SiHa cells by kafirins. Sorghum may be used as a nutraceutical with potential cancer-prevention benefits.

Introducción: el cáncer de cuello uterino es una de las principales causas de muerte en las mujeres de todo el mundo, tanto en los países desarrollados como en los países en desarrollo. Por lo tanto, es importante un tratamiento eficaz de este cáncer con posibles fármacos antitumorales. Sin embargo, se necesitan nuevos tratamientos inspirados en la medicina nutricional. Objetivo: usar las líneas celulares de cáncer cervicouterino humano HeLa y SiHa para evaluar la actividad antiproliferativa, apoptótica y migratoria del sorgo (kafirinas). Material y métodos: los efectos anticancerígenos de las kafirinas se examinaron mediante recuento de células, ensayos de MTT, apoptosis y ensayos de migración. Resultados: la presente investigación demostró que el sorgo induce la inhibición del crecimiento de las células HeLa y SiHa a un nivel significativo. La inhibición del crecimiento es dependiente de la dosis e irreversible. Cuando las células HeLa y SiHa fueron tratadas con sorgo debido a la actividad de las kafirinas, se observaron cambios morfológicos, los cuales se identificaron mediante la formación de cuerpos apoptóticos. Y las kafirinas en concentraciones de 37.5, 75, 150 y 300 µg/mL disminuyeron la migración de las células HeLa y SiHa. Conclusiones: este trabajo demuestra la inducción de actividad antiproliferativa, apoptótica y antimigratoria en las células HeLa y SiHa por parte de las kafirinas. El sorgo puede utilizarse como nutracéutico con potenciales beneficios en la prevención del cáncer.

Sodium Valproate Modulates the Methylation Status of Lysine Residues 4, 9 and 27 in Histone H3 of HeLa Cells.

BACKGROUND: Valproic acid/sodium valproate (VPA), a well-known anti-epileptic agent, inhibits histone deacetylases, induces histone hyperacetylation, promotes DNA demethylation, and affects the histone methylation status in some cell models. Histone methylation profiles have been described as potential markers for cervical cancer prognosis. However, histone methylation markers that can be studied in a cervical cancer cell line, like HeLa cells, have not been investigated following treatment with VPA. METHODS: In this study, the effect of 0.5 mM and 2.0 mM VPA for 24 h on H3K4me2/me3, H3K9me/me2 and H3K27me/me3 signals as well as on KMT2D, EZH2, and KDM3A gene expression was investigated using confocal microscopy, Western blotting, and RT-PCR. Histone methylation changes were also investigated by Fourier-transform infrared spectroscopy (FTIR). RESULTS: We found that VPA induces increased levels of H3K4me2/me3 and H3K9me, which are indicative of chromatin activation. Particularly, H3K4me2 markers appeared intensified close to the nuclear periphery, which may suggest their implication in increased transcriptional memory. The abundance of H3K4me2/me3 in the presence of VPA was associated with increased methyltransferase KMT2D gene expression. VPA induced hypomethylation of H3K9me2, which is associated with gene silencing, and concomitant with the demethylase KDM3A, it increased gene expression. Although VPA induces increased H3K27me/me3 levels, it is suggested that the role of the methyltransferase EZH2 in this context could be affected by interactions with this drug. CONCLUSION: Histone FTIR spectra were not affected by VPA under present experimental conditions. Whether our epigenetic results are consistent with VPA affecting the aggressive tumorous state of HeLa cells, further investigation is required.

Selective photodynamic effects on cervical adenocarcinoma cells provided by F127 Pluronic®-based micelles modulating hypericin delivery

Abstract Cervical cancer is a leading cause of death among women. The endocervical adenocarcinoma (ECA) represents an aggressive and metastatic type of cancer with no effective treatment options currently available. We evaluated the antitumoral and anti-migratory effects of hypericin (HYP) encapsulated on Pluronic F127 (F127/HYP) photodynamic therapy (PDT) against a human cell line derived from invasive cervical adenocarcinoma (HeLa) compared to a human epithelial cell line (HaCaT). The phototoxicity and cytotoxicity of F127/HYP were evaluated by the following assays: colorimetric assay, MTT, cellular morphological changes by microscopy and long-term cytotoxicity by clonogenic assay. In addition, we performed fluorescence microscopy to analyze cell uptake and subcellular distribution of F127/HYP, cell death pathway and reactive oxygen species (ROS) production. The PDT mechanism was determined with sodium azide and D-mannitol and cell migration by wound-healing assay. The treatment with F127/HYP promoted a phototoxic result in the HeLa cells in a dose-dependent and selective form. Internalization of F127/HYP was observed mainly in the mitochondria, causing cell death by necrosis and ROS production especially by the type II PDT mechanism. Furthermore, F127/HYP reduced the long-term proliferation and migration capacity of HeLa cells. Overall, our results indicate a potentially application of F127/HYP micelles as a novel approach for PDT with HYP delivery to more specifically treat ECA.

Synergistic effect of sorafenib with Platycladus orientalis (L) leaf extract on cervical cancer

The extracts of Platycladus orientalis (L.) Franco leaves have shown promising anti-cancer, anti-oxidant and anti-inflammatory potency with the traditional knowledge of healing HPV associated warts. The purpose of this research is to assess the synergistic activity of sorafenib and Platycladus orientalis (L) leaf extraction on cervical cancer cells. The cytotoxicity efficiency of different concentrations of Sorafenib and ethanol extract of Platycladus orientalis (L.) leaves were tested on HeLa cells by MTT and Trypan blue assays. The synergistic effect of the IC50 concentrations of Sorafenib and Platycladus orientalis (L.) on HeLa cell by MTT assay, and mRNA expression levels of tumor suppressor tazarotene-induced gene 3 (TIG3), proliferating cell nuclear antigen (PCNA) gene and apoptosis modulator (Bcl-2) gene by RT-PCR were evaluated with individual treatments. Combination treatment showed a relatively more expression of TIG3 and less expression of Bcl-2 and PCNA was observed. Growth factor-induced MAPKP activation was arrested by compound combination treatment, which and suppression of proliferation-induced apoptosis of cervical cancer cells. Based on the our results, the combination of sorafenib and crude leaf extract from Platycladus orientalis (L.) can effectively suppress cervical cancer cell growth, thereby providing an interesting rationale for further clinical trials and in-vivo studies.

Arracacia xanthorrhiza Bancr compounds decrease β-actin, hypoxia-inducible factor-1 and nitric oxide production in HeLa cells / Los componentes de la Arracacia xanthorrhiza Bancr disminuyen las producciones de la actina β, del factor-1 inducible por la hipoxia y del óxido nítrico en células Hela

Abstract The treatment of cancer patients with anti-cancer drugs is often accompanied by the presence of undesirable side effects. The use of natural plant derivatives alone, or in conjunction with existing anti-neoplastic drugs, has been suggested to obtain better results and decrease these side effects. Nitric oxide (NO•), the hypoxia-inducible factor-1 (HIF-1), and decreased concentration of actin play important roles in cancer progression. The beneficial effects of polyphenols in various organ disorders including cancer has been reported. The aim of this study was to determine the effect of Arracacia xanthorrhiza Bancr extracts, white (WAXB) and red (RAXB) variants (compounds rich in polyphenols) on the concentrations of β-actin, NO• and HIF-1 in Hela cells cultures, to uncover possible anti-neoplastic effects. Extracts from the plant leaves were added to Hela cell cultures at a concentration of 10-3 mg/mL, and after 24 hours of culture, the concentrations of β-actin, NO• and HIF-1 were determined by immunohistochemical, biochemical and western blot assays. Both extracts reduced the concentrations of β-actin, NO• and HIF-1 (p<0.001), similar to the methotrexate effect. These results suggest an antineoplastic effect of the studied plant extracts and highlight the possibility of their use in the treatment of neoplasms.

Resumen El tratamiento de pacientes con cáncer utilizando drogas-antineoplásicas presenta problemas relacionados con efectos colaterales indeseables. Se ha sugerido el uso de derivados de plantas naturales solas, o en combinación con drogas antineoplásicas existentes para obtener mejores resultados y disminuir los efectos colaterales. Así mismo, se ha reportado que el óxido nítrico (NO•), el factor-1 inducible por hipoxia (HIF-1) y la disminución de la expresión de la actina tienen un papel en la progresión del cáncer. También se ha reportado los efectos beneficiosos de lo polifenoles en varios desordenes orgánicos, incluyendo el cáncer. El objetivo de este estudio fue determinar los efectos de los extractos procedentes de la Arracacia xanthorrhiza Bancr blanca (AXBB) y la variedad roja (AXBR) (compuestos ricos en polifenoles) en las concentraciones de la actina-beta, el NO• y el HIF-1 en cultivo de células Hela, para destacar sus posibles efectos antineoplásicos. A los cultivos de células Hela se les agregaron los extractos de las hojas de AXBB o AXBR (10-3 mg/mL, concentración final) y después de 24 horas de cultivo se determinaron las concentraciones de la actina-beta, el NO• y el HIF-1 por métodos inmunohistoquímicos, bioquímicos y western blot. Ambos extractos disminuyeron las concentraciones de la actina-beta, el NO• y el HIF-1 (p<0,001) de una manera similar al efecto del metotrexato. Estos resultados sugieren un efecto antineoplásico de estos extractos y destacan la posibilidad de ser usados para el tratamiento de las neoplasias.

Cytotoxic effect of carbohydrate derivatives of digitoxigenin involves modulation of plasma membrane Ca2+ -ATPase.

Cardiac glycosides, such as digoxin and digitoxin, are compounds that interact with Na+ /K+ -ATPase to induce anti-neoplastic effects; however, these cardiac glycosides have narrow therapeutic index. Thus, semi-synthetic analogs of digitoxin with modifications in the sugar moiety has been shown to be an interesting approach to obtain more selective and more effective analogs than the parent natural product. Therefore, the aim of this study was to assess the cytotoxic potential of novel digitoxigenin derivatives, digitoxigenin-α-L-rhamno-pyranoside (1) and digitoxigenin-α-L-amiceto-pyranoside (2), in cervical carcinoma cells (HeLa) and human diploid lung fibroblasts (Wi-26-VA4). In addition, we studied the anticancer mechanisms of action of these compounds by comparing its cytotoxic effects with the potential to modulate the activity of three P-type ATPases; Na+ /K+ -ATPase, sarco/endoplasmic reticulum Ca2+ -ATPase (SERCA), and plasma membrane Ca2+ -ATPase (PMCA). Briefly, the results showed that compounds 1 and 2 were more cytotoxic and selectivity for HeLa tumor cells than the nontumor cells Wi-26-VA4. While the anticancer cytotoxicity in HeLa cells involves the modulation of Na+ /K+ -ATPase, PMCA and SERCA, the modulation of these P-type ATPases was completely absent in Wi-26-VA4 cells, which suggest the importance of their role in the cytotoxic effect of compounds 1 and 2 in HeLa cells. Furthermore, the compound 2 inhibited directly erythrocyte ghosts PMCA and both compounds were more cytotoxic than digitoxin in HeLa cells. These results provide a better understanding of the mode of action of the synthetic cardiac glycosides and highlights 1 and 2 as potential anticancer agents.

Transforming growth factor (TGF)-ß1 and interferon (IFN)-γ differentially regulate ICAM-1 expression and adhesion of Toxoplasma gondii to human trophoblast (BeWo) and uterine cervical (HeLa) cells.

Toxoplasma gondii is a parasite able to infect various cell types, including trophoblast cells. Studies have demonstrated that interleukin (IL)-10, transforming growth factor (TGF)-ß1 and interferon (IFN)-γ are involved in the susceptibility of BeWo trophoblast cells to T. gondii infection. Furthermore, T. gondii is able to adhere to the plasma membrane of host cells through intercellular adhesion molecule (ICAM)-1. Thus, the present study aimed to assess the role of IL-10, TGF-ß1 and IFN-γ in the expression of ICAM-1 in BeWo and HeLa cells and to analyze the role of ICAM-1 in the adhesion and invasion of T. gondii to these cells under the influence of these cytokines. For this purpose, BeWo and HeLa cells were treated or not, before and after T. gondii infection, with rIL-10, rTGF-ß1 or rIFN-γ. For the BeWo cells, rIL-10 and rTGF-ß1 favored susceptibility to infection, but only rTGF-ß1 and rIFN-γ increased ICAM-1 expression, and TNF-α release. On the other hand, rIFN-γ downregulated the expression of ICAM-1 triggered by T. gondii in HeLa cells, leading to control of the infection. Moreover, we observed that upregulation of ICAM-1, mediated by cytokine's stimulation, in BeWo and HeLa cells resulted in a high number rate of both parasite adhesion and invasion to these cells, which were strongly reduced after ICAM-1 neutralization. Likewise, the blockage of ICAM-1 molecule also impaired T. gondii infection in human villous explants. Taken together, these findings demonstrate that TGF-ß1 and IFN-γ differentially regulate ICAM-1 expression, which may interfere in the adhesion/invasion of T. gondii to BeWo and HeLa cells for modulating susceptibility to infection.

Biogenic silver nanoparticles (AgNp-Bio) reduce Toxoplasma gondii infection and proliferation in HeLa cells, and induce autophagy and death of tachyzoites by apoptosis-like mechanism.

Toxoplasma gondii is a protozoan parasite that can cause severe and debilitating diseases, especially in immunocompromised individuals. The available treatment is based on drugs that have low efficacy, high toxicity, several adverse effects, and need long periods of treatment. Thus, the search for therapeutic alternatives is urgently needed. Biogenic silver nanoparticles (AgNp-Bio) have been associated with several biological effects, as antiproliferative, pro-apoptotic, antioxidant, antiviral, antifungal, and antiprotozoal activity. Thus, the objective was evaluating AgNp-Bio effect on HeLa cells infected with T. gondii (RH strain). First, nontoxic AgNp-Bio concentrations for HeLa cells (1.5 - 6 µM) were determined, which were tested on cells infected with T. gondii. A significant reduction in infection, proliferation, and intracellular parasitic load was observed, also an increase in ROS and IL-6. Additionally, the evaluation of the action mechanisms of the parasite showed that AgNp-Bio acts directly on tachyzoites, inducing depolarization of the mitochondrial membrane, ROS increase, and lipid bodies accumulation, as well as triggering an autophagic process, causing damage to the parasite membrane, and phosphatidylserine exposure. Based on this, it was inferred that AgNp-Bio affects T. gondii by inducing immunomodulation and microbicidal molecules produced by infected cells, and acts on parasites, by inducing autophagy and apoptosis.

Moringa oleifera extract promotes apoptosis-like death in Toxoplasma gondii tachyzoites in vitro.

Toxoplasma gondii is the causative agent of toxoplasmosis, and an important problem of public health. The current treatment for toxoplasmosis is the combination of pyrimethamine and sulphadiazine, which do not act in the chronic phase of toxoplasmosis and have several side-effects. This study evaluated the anti-T. gondii activity and potential mechanism of Moringa oleifera seeds' aqueous extract in vitro. The concentration of M. oleifera extract in HeLa cells was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide cell viability assays. The presence of T. gondii was assessed by quantitative polymerase chain reaction and toluidine blue staining. Pyrimethamine and sulphadiazine were used as drug controls. Modifications in T. gondii morphology and ultrastructure were observed by electron microscopy. In vitro, the M. oleifera extract had no toxic effect on HeLa cells at concentrations below 50 µg mL−1. Moringa oleifera extract inhibits T. gondii invasion and intracellular proliferation with similar results for sulphadiazine + pyrimethamine, and also shows cellular nitric oxide production at a concentration of 30 µg mL−1. Electron microscopy analyses indicated structural and ultrastructural modifications in tachyzoites after treatment. We also observed an increase in reactive oxygen species production and a loss of mitochondrial membrane integrity. Nile Red staining assays demonstrated a lipid accumulation. Annexin V­fluorescein isothiocyanate and propidium iodide staining demonstrated that the main action of M. oleifera extract in T. gondii tachyzoites was compatible with late apoptosis. In conclusion, M. oleifera extract has anti-T. gondii activity in vitro and might be a promising substance for the development of a new anti-T. gondii drug.

Nanobiomechanical behavior of Fe3O4@SiO2and Fe3O4@SiO2-NH2nanoparticles over HeLa cells interfaces.

In this work, we studied the impact of magnetic nanoparticles (MNPs) interactions with HeLa cells when they are exposed to high frequency alternating magnetic field (AMF). Specifically, we measured the nanobiomechanical properties of cell interfaces by using atomic force microscopy (AFM). Magnetite (Fe3O4) MNPs were synthesized by coprecipitation and encapsulated with silica (SiO2): Fe3O4@SiO2and functionalized with amino groups (-NH2): Fe3O4@SiO2-NH2, by sonochemical processing. HeLa cells were incubated with or without MNPs, and then exposed to AMF at 37 °C. A biomechanical analysis was then performed through AFM, providing the Young's modulus and stiffness of the cells. The statistical analysis (p < 0.001) showed that AMF application or MNPs interaction modified the biomechanical behavior of the cell interfaces. Interestingly, the most significant difference was found for HeLa cells incubated with Fe3O4@SiO2-NH2and exposed to AMF, showing that the local heat of these MNPs modified their elasticity and stiffness.

(PhSe)2 and (pCl-PhSe)2 organochalcogen compounds inhibit Candida albicans adhesion to human endocervical (HeLa) cells and show anti-biofilm activities.

Adhesion capacity on biological surfaces and biofilm formation is considered an important step in the infection process by Candida albicans. The ability of (PhSe)2 and (pCl-PhSe)2, two synthetic organic selenium (organochalcogen) compounds, to act on C. albicans virulence factors related to adhesion to human endocervical (HeLa) cell surfaces and their anti-biofilm activities was analyzed. Both organochalcogen compounds inhibited C. albicans adhesion to HeLa cells, dependent on compound concentrations. (PhSe)2 (at 20 µM; p = 0.0012) was significantly more effective than (pCl-PhSe)2 (at 20 µM; p = 0.0183) compared with the control. (PhSe)2 inhibited biofilm formation and decreased biofilm viability in both early and mature biofilms more efficiently than (pCl-PhSe)2. Overall, the organochalcogen compounds, especially (PhSe)2, were demonstrated to be effective antifungal drugs against C. albicans virulence factors related to epithelial cell surface adhesion and the formation and viability of biofilms.

Epigenetic Evaluation of N-(2-hydroxyphenyl)-2-Propylpentanamide, a Valproic Acid Aryl Derivative with Activity Against HeLa Cells.

BACKGROUND: Valproic acid (VPA) is an HDAC inhibitor (HDACI) with an anticancer activity, but is hepatotoxic. N-(2-hydroxyphenyl)-2-propylpentanamide (o-OH-VPA) is a VPA aryl derivative designed in silico as a selective inhibitor of HDAC8 with biological properties against HeLa, rhabdomyosarcoma and breast cancer cell cultures. OBJECTIVE: We studied the epigenetic mechanism of o-OH-VPA as an HDACI and evaluated whether it was toxic to normal cells. METHODS: HeLa cells and primary human fibroblasts were used for this study as carcinogenic and normal cells, respectively. Cell survival was evaluated by MTT assay, whereas viability and doubling time were determined by the Trypan-blue method. HDAC activity was tested using the colorimetric HDAC activity assay. The expression of p21 was analyzed by PCR and HDAC8 expression was also evaluated by real-time PCR. Cell cycle and caspase-3 activity were analyzed by flow cytometry and caspase-3 colorimetric assay, respectively. RESULTS: o-OH-VPA (IC50 = 0.1 mM) was fifty-eight times more effective than VPA (IC50 = 5.8 mM) to reduce HeLa cell survival. Furthermore, o-OH-VPA increased the doubling time of HeLa cells by 33% with respect to the control. o-OH-VPA acted as HDACI in HeLa cells without affecting the HDAC8 expression, arresting the cell cycle of HeLa cells in the G0/G1 phase due to the increase in p21 expression with the inhibition of caspase-3 activity without exhibiting toxicity toward normal cells. CONCLUSION: Our results revealed that o-OH-VPA is an HDACI with a selective effect against HeLa cells but without the known toxicity exerted by most pan-HDACIs on normal cells.

Trypanocidal activity of South American Vernonieae (Asteraceae) extracts and its sesquiterpene lactones.

Chagas disease is caused by Trypanosoma cruzi and affects the poorest population in the Americas. Fourteen plant extracts and seventeen sesquiterpene lactones from the tribe Vernonieae (Asteraceae), were evaluated for the first time against T. cruzi. Cytotoxicity employing HeLa cells was also assessed. The best results were obtained with leaves and flowers rinse extracts from Vernonanthura nebularum (E-1 and E-3) and Elephantopus mollis (E-11 and E-13), with IC50 values <2 µg/mL, being E-1 the most active (IC50 = 0.8 µg/mL). Additionally, these extracts displayed a good selectivity (SI > 10). The most active sesquiterpene lactones, isolated from the extracts, were 2 (2-methoxy-2,5-epoxy-8-methacryloxygermacra-3Z,11(13)-dien-6,12-olide) and 6 (2-ethoxy-2,5-epoxy-8-angeloxygermacra-3Z,11(13)-dien-6,12-olide) from V. nebularum and 12 (8α-methacryloxyhirsutinolide 13-O-acetate) from V. pinguis, with IC50 of 1.5, 2.1 and 2.0 µM, respectively. These compounds showed SI values >14, better than those of the reference drug nifurtimox. Plants living in South American ecosystems could become a potential source of trypanocidal agents.

Chitosan microparticles as entrapment system for trans- cinnamaldehyde: Synthesis, drug loading, and in vitro cytotoxicity evaluation.

The ionic gelation method was used to study the effect of the crosslinking agent, sodium tripolyphosphate on average particle size (Dp) and zeta potential (ζp) of chitosan microparticles (CSMP) unloaded and loaded with trans-cinnamaldehyde (TCIN). The obtained values of Dp and ζp trend as 117.6 ±â€¯0.4 ≤ Dp ≤ 478.5 ±â€¯3.5 nm and +27.8 ±â€¯1.3 ≤ ζp ≤ +103.5 ±â€¯4.2 mV, respectively. The entrapment efficiency of TCIN in CSMP was 9.1 ±â€¯2.0% and 71.5 ±â€¯2.9% was released after 360 min (pH = 6.5) which reveals a potential anti-cancer activity in acidic environment. Cytotoxicity of TCIN in DMSO (0-50 µM) was evaluated on MDCK and HeLa cell lines and exhibited low effect at either 24 or 48 h of exposure; whereas TCIN-loaded CSMP (0-50 µM) showed, after 24 h of exposure, 67.6 ±â€¯7.0 and 64.5 ±â€¯3.9% cytotoxicity for MDCK and HeLa cell lines, respectively. At 48 h of exposure, TCIN-loaded CSMP achieved 81.1 ±â€¯0.26 and 77.9 ±â€¯4.2% cytotoxicity for MDCK and HeLa cell lines, respectively.