Pericyte perivascular cells, believed to originate mesenchymal stem cells (MSC), are characterized by their capability to differentiate into various phenotypes and participate in tissue reconstruction of different organs, including the brain. We show that these cells can be induced to differentiation into neural‐like phenotypes. For these studies, pericytes were obtained from aorta ex‐plants of Sprague–Dawley rats and differentiated into neural cells following induction with trans retinoic acid (RA) in serum‐free defined media or differentiation media containing nerve growth and brain‐derived neuronal factor, B27, N2, and IBMX. When induced to differentiation with RA, cells express the pluripotency marker protein stage‐specific embryonic antigen‐1, neural‐specific proteins β3‐tubulin, neurofilament‐200, and glial fibrillary acidic protein, suggesting that pericytes undergo differentiation, similar to that of neuroectodermal cells. Differentiated cells respond with intracellular calcium transients to membrane depolarization by KCl indicating the presence of voltage‐gated ion channels and express functional N‐methyl‐D‐aspartate receptors, characteristic for functional neurons. The study of neural differentiation of pericytes contributes to the understanding of induction of neuroectodermal differentiation as well as providing a new possible stem‐cell source for cell regeneration therapy in the brain. © 2011 International Society for Advancement of Cytometry

We investigated the regulation of the Ca²⁺-activated K⁺(maxi-K⁺) channel by angiotensin II (ANG II) and its synthetic analog, [Lys²]ANG II, in freshly dispersed intestinal myocytes. We identified a maxi-K⁺channel population in the inside-out patch configuration on the basis of its conductance (257 ± 4 pS in symmetrical 150 mM KCl solution), voltage and Ca²⁺dependence of channel opening, low Na⁺-to-K⁺and Cl⁻-to-K⁺permeability ratios, and blockade by external Cs⁺and tetraethylammonium chloride. ANG II and [Lys²]ANG II caused an indirect, reversible, Ca²⁺- and dose-dependent activation of maxi-K⁺channels in cell-attached experiments when cells were bathed in high-K⁺solution. This effect was reversibly blocked by DUP-753, being that it is mediated by the AT₁receptor. Evidences that activation of the maxi-K⁺channel by ANG II requires a rise in intracellular Ca²⁺concentration ([Ca²⁺]_i) as an intermediate step were the shift of the open probability of the channel-membrane potential relationship to less positive membrane potentials and the sustained increase in [Ca²⁺]_iin fura 2-loaded myocytes. The preservation of the pharmacomechanical coupling of ANG II in these cells provides a good model for the study of transmembrane signaling responses to ANG II and analogs in this tissue.

Astaxanthin (AST) is a valued molecule because of its high antioxidant properties. However, AST is extremely sensitive to oxidation, causing the loss of its bioactive properties. The purposes of this study were to define conditions for microencapsulating AST in oil bodies (OB) from Brassica napus to enhance its oxidative stability, and to test the bioactivity of the microencapsulated AST (AST-M) in cells. Conditions for maximising microencapsulation efficiency (ME) were determined using the Response Surface Methodology, obtaining a high ME (>99%). OB loaded with AST showed a strong electrostatic repulsion in a wide range of pH and ionic strengths. It was found that AST-M exposed to air and light was more stable than free AST. In addition, the protective effect of AST against intracellular ROS production was positively influenced by microencapsulation in OB. These results suggest that OB offer a novel option for stabilising and delivering AST.

Hypertension is a systemic condition with high morbidity and mortality rates worldwide, which poses an increased risk for cardiovascular diseases. In this study, we demonstrated the antioxidant and vasodilator activity of Ugni molinae Turcz. (Murtilla) fruit, a berry native to Chile and proposed models to explain its modulatory mechanism in hypotensive response. Murtilla fruits were cultivated in a germplasm bank and submitted to chemical and biological analyses. The phenolic compounds gallic acid, Catechin, Quercetin‐3‐β‐D‐glucoside, Myricetin, Quercetin, and Kaempferol were identified. Murtilla extract did not generate toxic effects on human endothelial cells and had significant antioxidant activity against ROS production, lipid peroxidation, and superoxide anion production. Furthermore, it showed dose‐dependent vasodilator activity in aortic rings in the presence of endothelium, whose hypotensive mechanism is partially mediated by nitric oxide synthase/guanylate cyclase and large‐conductance calcium‐dependent potassium channels. Murtilla fruits might potentially have beneficial effects on the management of cardiovascular diseases.