In Vitro and Sensory Evaluation of Capsaicin-Loaded Nanoformulations

Capsaicin has known health beneficial and therapeutic properties. It is also able to enhance the permeability of drugs across epithelial tissues. Unfortunately, due to its pungency the oral administration of capsaicin is limited. To this end, we assessed the effect of nanoencapsulation of capsaicin, under the hypothesis that this would reduce its pungency. Core-shell nanocapsules with an oily core and stabilized with phospholipids were used. This system was used with or without chitosan coating. In this work, we investigated the in vitro release behavior of capsaicin-loaded formulations in different physiological media (including simulated saliva fluid). We also evaluated the influence of encapsulation of capsaicin on the cell viability of buccal cells (TR146). To study the changes in pungency after encapsulation we carried out a sensory analysis with a trained panel of 24 students. The in vitro release study showed that the systems discharged capsaicin slowly in a monotonic manner and that the chitosan coating had an effect on the release profile. The cytotoxic response of TR146 cells to capsaicin at a concentration of 500 μM, which was evident for the free compound, was reduced following its encapsulation. The sensory study revealed that a chitosan coating results in a lower threshold of perception of the formulation. The nanoencapsulation of capsaicin resulted in attenuation of the sensation of pungency significantly. However, the presence of a chitosan shell around the nanoformulations did not mask the pungency, when compared with uncoated systems.     

A purine permease in Candida glabrata

Abstract Competition experiments revealed that adenine and guanine were transported by a purine permease in both Candida glabrata 4 and a C. glabrata 4 cytosine permease negative mutant. The C. glabrata 4 cytosine permease negative mutant was isolated using 5-fluorocytosine selection. This mutant no longer transported cytosine, but transported adenine and guanine. A transport system for hypoxanthine was not detected. Hence, in addition to the cytosine permease, a purine permease exists in C. glabrata . This differs from the purine cytosine permeases in Saccharomyces cereuisiae and Candida albicans which transport adenine, cytosine, guanine and hypoxanthine.     

When the Background Matters: Using Scenarios from Integrated Assessment Models in Prospective Life Cycle Assessment

Prospective life cycle assessment (LCA) needs to deal with the large epistemological uncertainty about the future to support more robust future environmental impact assessments of technologies. This study proposes a novel approach that systematically changes the background processes in a prospective LCA based on scenarios of an integrated assessment model (IAM), the IMAGE model. Consistent worldwide scenarios from IMAGE are evaluated in the life cycle inventory using ecoinvent v3.3. To test the approach, only the electricity sector was changed in a prospective LCA of an internal combustion engine vehicle (ICEV) and an electric vehicle (EV) using six baseline and mitigation climate scenarios until 2050. This case study shows that changes in the electricity background can be very important for the environmental impacts of EV. Also, the approach demonstrates that the relative environmental performance of EV and ICEV over time is more complex and multifaceted than previously assumed. Uncertainty due to future developments manifests in different impacts depending on the product (EV or ICEV), the impact category, and the scenario and year considered. More robust prospective LCAs can be achieved, particularly for emerging technologies, by expanding this approach to other economic sectors beyond electricity background changes and mobility applications as well as by including uncertainty and changes in foreground parameters. A more systematic and structured composition of future inventory databases driven by IAM scenarios helps to acknowledge epistemological uncertainty and to increase the temporal consistency of foreground and background systems in LCAs of emerging technologies.     

Triacylbenzenes and long-chain volatile ketones from Cochlospermum tinctorium rhizome

The composition of the volatile fraction from Cochlospermum tinctorium rhizome was investigated by GC and GC-MS; among 11 constituents detected, eight were identified as straight chain ketonic compounds. In addition, five triacylbenzenes were isolated from a petrol extract of the rhizome, separated by HPLC and identified by their spectral data.     

Estrogen induces normal murine CD5+ B cells to produce autoantibodies

Females have better humoral immune responses and are more susceptible to autoimmune diseases than males. Normal female mice (C57BL/6J, C3H/HeJ, and NZW) have significantly increased spontaneous autoimmune plaque-forming cells (APFC) to mouse erythrocytes pretreated with bromelain (Br-ME) in spleen, peritoneal exudate cell, and bone marrow compared to their male counterparts. A minor subpopulation of B cells, CD5+ B, is thought to produce this autoantibody. As determined by dual color flow cytometry, increased APFC to Br-ME in females is not due to quantitative increase of CD5+ B cells. Rather, it is due to increased numbers or percentages) of CD5+ B cells producing these autoantibodies, because CD5+ B cells from females produced greater numbers of APFC to Br-ME than equal numbers of cells derived from males. The increased autoantibody production in females can be attributed to the effect of estrogen on the immune response because this hormone markedly augments APFC to Br-ME in intact or orchidectomized males. Male hormone had little effect. Importantly, estrogen did not increase the numbers of B or CD5+ B cells but augmented the ability of B cells to produce this response. This was verified when a T cell-depleted B cell fraction or fluorescence-activated cell sorter purified CD5+ B cells from estrogen-treated mice proved more efficient in the production of APFC to Br-ME. These results suggest that the number of CD5+ B cells committed to produce autoantibodies to Br-ME is increased under the influence of estrogen. This is the first demonstration that estrogen can augment the production of natural autoantibodies in normal mice. The overall augmented humoral immune responses in females and the B cell hyperactivity in female predominant autoimmune diseases appears to be due to estrogen.     

Impact on energy metabolism of quantitative and functional cyclosporine-induced damage of kidney mitochondria

In this study we have measured, under experimental conditions which maintained efficient coupling, respiratory intensity, respiratory control, oxidative phosphorylation capacity and protonmotive force. Succinate cytochrome-c reductase and cytochrome-c oxidase activities were also studied. These investigations were carried out using kidney mitochondria from cyclosporine-treated rats (in vivo studies) and from untreated rats in the presence of cyclosporine (in vitro studies). Inhibition of respiratory intensity by cyclosporine did not exceed 21.1% in vitro and 15.9% in vivo. Since there was no in vitro inhibition of succinate cytochrome-c reductase and cytochrome-c oxidase activities, the slowing of electron flow observed can be interpreted as a consequence of an effect produced by cyclosporine between cytochromes b and c₁. Cyclosporine had no effect on respiratory control either in vitro or in vivo. Statistically significant inhibition of the oxidative phosphorylation was observed both in vitro (6.6%) and in vivo (12.1%). Moreover, cyclosporine did not induce any change of membrane potential either in vivo or in vitro. Our findings show that cyclosporine is neither a protonophore, nor a potassium ionophore. In cyclosporine-treated rats we noticed a decrease of protein in subcellular fraction, including the mitochondrial fraction. The role of the inhibition respiratory characteristics by cyclosporine in nephrotoxicity in vivo must take account of these two parameters: inhibition of the respiratory characteristics measured in vitro and diminution of mitochondrial protein in cyclosporine-treated rats.