One-step rapid tracking and isolation of senescent cells in cellular systems, tissues, or animal models via GLF16.

Identification and isolation of senescent cells is challenging, rendering their detailed analysis an unmet need. We describe a precise one-step protocol to fluorescently label senescent cells, for flow cytometry and fluorescence microscopy, implementing a fluorophore-conjugated Sudan Black-B analog, GLF16. Also, a micelle-based approach allows identification of senescent cells in vivo and in vitro, enabling live-cell sorting for downstream analyses and live in vivo tracking. Our protocols are applicable to cellular systems, tissues, or animal models where senescence is present. For complete details on the use and execution of this protocol, please refer to Magkouta et al.1.

Interaction of Rhus typhina Tannin with Lipid Nanoparticles: Implication for the Formulation of a Tannin-Liposome Hybrid Biomaterial with Antibacterial Activity.

Tannins are natural plant origin polyphenols that are promising compounds for pharmacological applications due to their strong and different biological activities, including antibacterial activity. Our previous studies demonstrated that sumac tannin, i.e., 3,6-bis-O-di-O-galloyl-1,2,4-tri-O-galloyl-ß-D-glucose (isolated from Rhus typhina L.), possesses strong antibacterial activity against different bacterial strains. One of the crucial factors of the pharmacological activity of tannins is their ability to interact with biomembranes, which may result in the penetration of these compounds into cells or the realization of their activity on the surface. The aim of the current work was to study the interactions of sumac tannin with liposomes as a simple model of the cellular membrane, which is widely used in studies focused on the explanation of the physicochemical nature of molecule-membrane interactions. Additionally, these lipid nanovesicles are very often investigated as nanocarriers for different types of biologically active molecules, such as antibiotics. In the frame of our study, using differential scanning calorimetry, zeta-potential, and fluorescence analysis, we have shown that 3,6-bis-O-di-O-galloyl-1,2,4-tri-O-galloyl-ß-D-glucose interacts strongly with liposomes and can be encapsulated inside them. A formulated sumac-liposome hybrid nanocomplex demonstrated much stronger antibacterial activity in comparison with pure tannin. Overall, by using the high affinity of sumac tannin to liposomes, new, functional nanobiomaterials with strong antibacterial activity against Gram-positive strains, such as S. aureus, S. epidermitis, and B. cereus, can be formulated.

Development and physicochemical characterization of nanoliposomes with incorporated oleocanthal, oleacein, oleuropein and hydroxytyrosol.

Oleocanthal, oleacein, oleuropein and hydroxytyrosol comprise characteristic polyphenols of olive with high biological value. However, stability problems hinder their further investigation. Thus, in the present study they were incorporated in nanoliposomes by thin film hydration method. The particles sizes, PDI, zeta-potential and physicochemical stabilities of nanoliposomes were evaluated by light scattering methods while FTIR, XRD, TGA and DSC methods were carried out for further physicochemical characterization. Their micromorphology was illustrated by negative-staining TEM and Cryo-TEM, revealing well-dispersed round-shaped vesicles. According to in vitro release studies, oleocanthal and oleacein were rapidly released in a higher percentage than oleuropein and hydroxytyrosol and compatible with the Ritger-Peppas model release mechanism while only oleuropein liposomes were governed by anomalous diffusion of non-Fickian diffusion. Antioxidant assays showed that nanoliposomes presented comparable activity with pure compounds enabling them as suitable carriers for the delivery of olive active biophenols in the human organism.

Antihypertensive activity and molecular interactions of irbesartan in complex with 2-hydroxypropyl-ß-cyclodextrin.

Irbesartan (IRB) exerts beneficial effects either alone or in combination with other drugs on numerous diseases, such as cancer, diabetes, and hypertension. However, due to its high lipophilicity, IRB does not possess the optimum pharmacological efficiency. To circumvent this problem, a drug delivery system with 2-hydroxypropyl-ß-cyclodextrin (2-HP-ß-CD) was explored. The 1:1 complex between IRB and 2-HP-ß-CD was identified through ESI QTF HRMS. Dissolution studies showed a higher dissolution rate of the lyophilized IRB-2-HP-ß-CD complex than the tablet containing IRB at pH = 1.2. DSC results revealed the differences of the thermal properties between the complex and various mixtures consisting of the two components, namely IRB and 2-HP-ß-CD. Interestingly, depending on the way the mixture preparation was conducted, different association between the two components was observed. Molecular dynamics (MD) simulations predicted the favorable formation of the above complex and identified the dominant interactions between IRB and 2-HP-ß-CD. In vitro pharmacological results verified that the inclusion complex not only preserves the binding affinity of IRB for AT1R receptor, but also it slightly increases it. As the complex formulation lacks the problems of the tablet, our approach is a promising new way to improve the efficiency of IRB.