Cytotoxic activity of Crotalus molossus molossus snake venom-loaded in chitosan nanoparticles against T-47D breast carcinoma cells.

Nanomedicine has led to the development of new biocompatible and biodegradable materials able to improve the pharmaceutical effect of bioactive components, broadening the options of treatment for several diseases, including cancer. Additionally, some snake venom toxins have been reported to present cytotoxic activity in different tumor cell lines, making them an auspicious option to be used as cancer drugs. The present study aims to evaluate the cytotoxic activity of the northern black-tailed rattlesnake (Crotalus molossus molossus) venom-loaded chitosan nanoparticles (Cs-Venom NPs) against the T-47D breast carcinoma cell line. To do so, we first identified the significant proteins composing the venom; afterward, hemocompatibility and cytotoxic activity against tumoral cells were evaluated. The venom was then loaded into chitosan nanoparticles through the ionotropic gelation process, obtaining particles of 415.9±21.67 nm and ζ-potential of +28.3±1.17 mV. The Cs-Venom complex delivered the venom into the breast carcinoma cells, inhibiting their viability and inducing morphological changes in the T-47D cells. These features indicate that these nanoparticles are suitable for the potential use of C. m. molossus venom toxins entrapped within polymer nanoparticles for the future development and research of cancer drugs.

Bifunctional nickel-iminodiacetic acid-core-shell silica nanoparticles for the exclusion of high molecular weight proteins and purification of His-tagged recombinant proteins.

Herein, silica nanoparticles were synthesized and chemically modified with iminodiacetic acid (IDA) and Ni2+ ions surrounded by a bis-acrylamide polymeric shell to obtain a new core-shell immobilized metal affinity chromatography (IMAC) based material. These Ni2+-IDA-core-shell silica nanoparticles (Ni2+-IDA-CSS-NP) represent a new alternative for purification of His-tagged proteins and exclusion of high molecular weight (HMW) proteins at the same time. Nanoparticles presented a final size of 479.6 ± 6.9 nm determined by dynamic light scattering (DLS) and a surface charge of -37.2 ± 0.5 mV. Successful incorporation of the different compounds at every phase of synthesis was evidenced by ATR-FTIR analysis. Ni2+-IDA-CSS-NP were used for isolation of His-tagged spo0F (6His-spo0F) from E. coli lysate. Ni2+-IDA-CSS-NP presented a capacity of 4.16 ± 0.45 µg mg-1. Purification of 6His-spo0F with high selectivity and the effective exclusion of HMW proteins were evidenced by SDS-PAGE and validated through mass spectrometry analysis.

Specific capture of glycosylated graphene oxide by an asialoglycoprotein receptor: a strategic approach for liver-targeting.

In this work, we report the evaluation of lactosylated graphene oxide (GO-AL) as a potential drug carrier targeted at an asialoglycoprotein receptor (ASGPR) from hepatic cancer cells. Structural-modification, safety evaluation, and functional analysis of GO-AL were performed. The structure and morphology of the composite were analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), while Raman and FTIR spectroscopy were used to track the chemical modification. For the safe application of GO-AL, an evaluation of the cytotoxic effect, hemolytic properties, and specific interactions of the glycoconjugate were also studied. SEM and AFM analysis of the GO showed graphene sheets with a layer size of 2-3 nm, though a few of them reached 4 nm. The Raman spectra presented characteristic peaks of graphene oxide at 1608 cm-1 and 1350 cm-1, corresponding to G and D bands, respectively. Besides, Si-O peaks for the APTES conjugates of GO were identified by FTIR spectroscopy. No cytotoxic or hemolytic effects were observed for GO samples, thus proving their biocompatibility. The interaction of Ricinus communis lectin confirmed that GO-AL has a biorecognition capability and an exposed galactose structure. This biorecognition capability was accompanied by the determination of the specific absorption of lactosylated GO by HepG2 cells mediated through the asialoglycoprotein receptor. The successful conjugation, hemolytic safety, and specific recognition described here for lactosylated GO indicate its promise as an efficient drug-delivery vehicle to hepatic tissue.

Effect of gamma irradiation doses in the structural and functional properties of mice splenic cells.

PURPOSE: Ionizing radiation is nowadays effectively used in cancer treatments. However, the effect of irradiation in immune-system cells is poorly understood and remains controversial. The aim of this work was to determine the effect of γ-irradiation in the structural and functional properties of mice splenic cells. MATERIALS AND METHODS: Structural traits of irradiated splenic cells were evaluated by Atomic Force Microscopy and Raman spectroscopy. Functional properties were measured by gene and protein expression by RT-qPCR and ELISA, respectively. The induced cytotoxic effect was evaluated by MTT assay and the phagocytic capability by flow cytometry. RESULTS: Membrane roughness and molecular composition of splenic adherent cells are not changed by irradiation doses exposure. An increase in transcription of pro-inflammatory cytokines was observed. While protein expression decreased in IL-2 dose-dependent, relevant differences were identified in the anti-inflammatory marker IL-10 at 27 Gy. An increase of cytotoxicity in irradiated cells at 7 Gy and 27 Gy doses was observed, while phagocytosis was slight increased at 7 Gy dose but not statistically significant. CONCLUSIONS: We have demonstrated that γ-irradiation affects the splenic cells and changes the cytokines profile toward a pro-inflammatory phenotype and a tendency to increase the cytotoxicity was found, which implies a stimulation of immune response induced by γ-irradiation.

Molecular recognition of glyconanoparticles by RCA and E. coli K88 - designing transports for targeted therapy.

The targeted drug delivery has been studied as one of the main methods in medicine to ensure successful treatments of diseases. Pharmaceutical sciences are using micro or nano carriers to obtain a controlled delivery of drugs, able to selectively interact with pathogens, cells or tissues. In this work, we modified bovine serum albumin (BSA) with lactose, obtaining a neoglycan (BSA-Lac). Subsequently, we synthesized glyconanoparticles (NPBSA-Lac) with the premise that it would be recognized by microbial galactose specific lectins. NPBSA-Lac were tested for bio-recognition with adhesins of E. coli K88 and Ricinus communis agglutinin I (RCA). Glycation of BSA with lactose was analyzed by electrophoresis, infrared spectroscopy and fluorescence. Approximately 41 lactoses per BSA molecule were estimated. Nanoparticles were obtained using water in oil emulsion method and spheroid morphology with a range size of 300-500 nm was observed. Specific recognition of NPBSA-Lac by RCA and E. coli K88 was displayed by aggregation of nanoparticles analyzed by dynamic light scattering and atomic force microscopy. The results indicate that the lactosylated nanovectors could be targeted at the E. coli K88 adhesin and potentially could be used as a transporter for an antibacterial drug.