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.

Atomic force microscopy and Raman spectra profile of blood components associated with exposure to cigarette smoking.

Tobacco smoke contains several compounds with oxidant and pro-oxidant properties with the capability of producing structural changes in biomolecules, as well as cell damage. This work aimed to describe and analyse the effect of tobacco smoke on human blood components, red blood cell (RBC) membrane, haemoglobin (Hb) and blood plasma by Atomic Force Microscopy (AFM) and Raman spectroscopy. Our results indicate that tobacco induced RBC membrane nano-alterations characterized by diminished RBC diameter and increased nano-vesicles formation, and RBC fragility. The Raman spectra profile suggests modifications in chemical composition specifically found in peaks 1135 cm-1, 1156 cm-1, 1452 cm-1 and intensity relation of peaks 1195 cm-1 and 1210 cm-1 of blood plasma and by change of peaks 1338 cm-1, 1357 cm-1, 1549 cm-1 and 1605 cm-1 associated with the pyrrole ring of Hb. The relevance of these results lies in the identification of a profile of structural and chemical alterations that serves as a biomarker of physiological and pathological conditions in the human blood components induced by tobacco exposure using AFM and the Raman spectroscopy as tools for monitoring them.

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.

Muscle lysyl oxidase activity and structural/thermal properties of highly cross-linked collagen in jumbo squid (Dosidicus gigas) mantle, fins and arms.

Muscle from mantle, fins and arms of squid (Dosidicus gigas) were compared based on lysyl oxidase activity (LOX), chemical/structural and thermodynamic properties of highly cross-linked collagen. The arms collagen presented the highest temperature (Tp) and enthalpy of transition. The arms collagen thermic properties may be explained by the higher imino amino acid content, proline and lysine hydroxylation degrees. Moreover, among the regions, the collagen from the arms had a more intense ß band chain, hydroxymerodesmosine peak in the resonance magnetic nuclear spectra and pyridinoline peak in the Raman spectra. Fins showed the highest LOX activity. The LOX activity was associated with the Tp, proline and lysine hydroxylation degrees. These results implied that the collagen in the arms was more intermolecularly ordered than the mantle and fins, and may provide a theoretical basis for a better understanding of the thermal behaviour of squid tissues during management and processing.