María J. Núñez

Antiradical Activity, Phenolics Profile, and Hydroxymethylfurfural in Espresso Coffee: Influence of Technological Factors

The influence of technological factors (decaffeination, brew volume, coffee species, and roast degree) on antiradical activity and phenolics content of espresso coffee is described. The screenings of phenolics profile and other compounds (caffeine and trigonelline), as well as the quantification of hydroxymethylfurfural, were performed by LC-DAD-ESI-MS. Significantly lower (p < 0.05) scavenging activities and phenolics contents were found in decaffeinated espressos when compared with regular ones (32 vs 38% and 324 vs 410 mg/30 mL cup, respectively). A long espresso (70 mL) offers more than twice the phenolics amount of a short one (20 mL). Robusta brews showed higher (p < 0.05) antiradical activity and phenolic contents than arabica ones, for all roast degrees (light, medium, and dark). No significant differences (p > 0.05) were observed for scavenging activities of differently roasted robusta brews, whereas an increase in medium-dark brews was observed for arabica samples. Total phenolics in robusta espressos decreased (p < 0.05) with the increase of roast degree, but no significant differences (p > 0.05) were found between arabica espressos from different roasts. By LC-DAD-ESI-MS, 23 hydroxycinnamic derivatives were found, including chlorogenic acids, lactones, and cinnamoyl-amino acid conjugates. The amount of each compound was differently affected by species and roast. Robusta brews presented superior levels of caffeine and chlorogenic acids, whereas arabica ones contained more trigonelline. Hydroxymethylfurfural contents in the brew (30 mL) varied from 2.60 to 0.84 mg for light- and dark-roasted arabicas and from 1.29 to 0.68 mg for light- and dark-roasted robustas, respectively.

Serotonin upregulates the activity of phagocytosis through 5-HT1A receptors

In this study, we investigated whether serotonin could regulate the in vitro activity of phagocytosis through 5‐hydroxytryptamine or serotonin (5‐HT1A) receptors. Mouse peritoneal macrophages were cultured with serotonin and the activity of phagocytosis was assessed by the uptake of zymosan and latex particles added to the culture media. Specific binding of [3H]8‐OH‐DPAT and immunohistochemistry using an affinity‐purified anti‐5‐HT1A‐receptor antibody were assayed in the macrophages. In addition, we took advantage of the availability of pharmacological inhibitors of nuclear factor‐κB (NF‐κB) to explore its role in the regulation of the 5‐HT1A receptor. Serotonin increased the in vitro activity of phagocytosis in a dose‐dependent manner. The 5‐HT1A receptor agonist (±)‐8‐hydroxy‐2‐(di‐n‐propyl‐amino)‐tetralin (R(+)‐8‐OH‐DPAT) reproduced these effects. Serotonin‐ or R(+)‐8‐OH‐DPAT‐induced increases in phagocytosis were blocked by the 5‐HT1A receptor antagonist WAY100635 and the NF‐κB inhibitor pyrrolidinedithiocarbamate. Moreover, mouse peritoneal macrophages expressed specific binding sites for [3H]8‐OH‐DPAT when cultivated in the presence of zymosan or latex beads. Immunohistochemistry confirmed the expression of the 5‐HT1A receptor protein in the macrophages. These results show that serotonin can upregulate the activity of peritoneal macrophages through 5‐HT1A receptors.

Music, immunity and cancer

The effects of music on the immune system and cancer development were evaluated in rodents subjected to sound stress. Animals were exposed daily to broad band noise around midnight and/or music for 5 hours on the following morning. Thymus and spleen cellularity, peripheral T lymphocyte population, the proliferative response of spleen cells to mitogen concanavalin A and natural killer cell activity were calculated in BALB/c mice. Sprague Dawley rats were injected i.v. with Walker 256 carcinosarcoma cells; 8 days later the rats were sacrificed and the number of metastatic nodules on the surface of the lungs was calculated macroscopically. Music reduced the suppressive effects of stress on immune parameters in mice and decreased the enhancing effects of stress on the development of lung metastases provoked by carcinosarcoma cells. Music enhanced the immune parameters and the anti-tumor response in unstressed rodents. Our data at present demonstrates that music can effectively reverse adverse effects of stress on the number and capacities of lymphocytes that are required for an optimal immunological response against cancer in rodents.

On the double role of surfactants as microalga cell lysis agents and antioxidants extractants

An integrated process based on the concomitant role of non-ionic surfactants as cell disrupters and organic extractants of intracellular antioxidants is proposed for the first time in this work. The lytic effect of two common families of surfactants on the cell walls of the microalga Tetraselmis suecica has been initially evaluated. The antioxidant extraction based on aqueous two-phase systems (ATPS) was proposed using different potential salting out agents such as sodium inorganic and organic salts in aqueous solutions of the selected surfactants. The extraction efficiency was ascertained for the most representative biomolecules previously detected in this microalga: α-tocopherol, β-carotene and gallic acid. The viability of the process was checked in real lyophilized microalga samples, yielding higher antioxidant activity than that provided by an ultrasound-based conventional method.

Effects of fluoxetine on cellular immune response in stressed mice

We studied the effects of fluoxetine, a non-tricyclic antidepressant drug that selectively inhibits re-uptake of serotonin by presinaptic neurons in the brain, on cellular immune responses in mice exposed to a chronic auditory stressor. The natural killer (NK) cell activity was reduced after 4, 8, 12, 16 and 20 days of stress exposure with a partial recovery on days 16 and 20. Daily treatment with fluoxetine partially reversed these adverse effects of stress in a dose-dependent manner. Significant differences appeared when fluoxetine was administered at 2 mg/kg and maximum effect was reached at doses of 5 mg/kg. The capacity of T cells to generate cytotoxic T-lymphocytes (CTL) in mixed lymphocyte cultures and in vivo was reduced after 4 days of stress application and this effect was partially reduced when mice were injected with 5 mg/kg of fluoxetine. Nevertheless, in our experiments, fluoxetine did not significantly affect the cellular immunity in unstressed mice. In conclusion, fluoxetine seems to partially recover the adverse effects of chronic stress on cellular immune response.

Effects of amphetamine on T-cell immune response in mice

Mice chronically injected with amphetamine (0.4 mg/kg/day) showed a reduction in thymus and spleen cellularity, and in peripheral T lymphocyte population. The blastogenic response of spleen lymphoid cells was assessed and amphetamine was found to inhibit T-cell proliferation. Amphetamine also reduced the capacity of mice to the development and passive transfer of immunity to Listeria monocytogenes.

Effects of fluoxetine on the immunosuppressive response to stress in mice

Mice exposed to a chronic auditory stressor and treated with fluoxetine (5 mg/kg) showed a reduction in stress-induced suppression of thymus and spleen cellularity, and in peripheral T lymphocyte population. The blastogenic response of spleen lymphoid cells and the delayed type hypersensitivity response (DTH) to sheep red blood cells (SRBC) were also assessed and fluoxetine was found to partially reverse the inhibitory effect of stress on both parameters.

Procyanidins from grape pomace are suitable inhibitors of human endothelial NADPH oxidase

Procyanidins have been associated with a reduced risk of cardiovascular diseases such as atherosclerosis. However, the molecular mechanisms underlying this benefit are not fully understood. Increased reactive oxygen species (ROS) production generated by nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is a common problem in different cardiovascular diseases. Our objective was to evaluate the effects of procyanidin‐rich fractions from distilled grape pomace on NADPH oxidase activity in human umbilical vein endothelial cells (HUVEC). Three differently polymerized and galloylated procyanidin fractions were analyzed for their NADPH oxidase inhibitory activity in cell lysates and in HUVEC cultures. All of the three fractions, up to 1 µg/ml, equally inhibited isolated NADPH oxidase in HUVEC lysates in a concentration‐dependent manner and independently of any superoxide anion scavenging activities. The procyanidin fractions even blocked NADPH oxidase activity in intact HUVEC, inhibiting ROS production at both extra‐ and intracellular levels. The fractions achieved the same effects that known NADPH oxidase inhibitors, such as diphenylene iodonium and apocynin, but they presented better hydrosolubility. Our results demonstrated that procyanidin from grape pomace inhibit human endothelial NADPH oxidase regardless of their polymerization degree and galloylation percentage. Therefore, procyanidins are suitable NADPH oxidase inhibitors which could serve as models for therapeutic alternatives for cardiovascular diseases. J. Cell. Biochem. 113: 1386–1396, 2012.

Identification of polymeric procyanidins from pine bark by mass spectrometry

Pine bark is an important source of polyphenolic compounds, mainly procyanidins, with reported protective effects against disease. In previous works, barks of two varieties of pine (P. pinaster and P. radiata) were extracted with ethanol, and partially purified to obtain the aqueous fractions (FA), that contained mainly polymeric procyanidins. The mean degree of polymerization was 7.9 for radiata (rFA) and 10.6 for pinaster (pFA). FAs were chromatographed on Sephadex LH-20 by using a gradient of methanol, water and acetone, to render a series of sub-fractions. In this work, the procyanidin compositions of these sub-fractions were analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The mass spectra of sub-fractions from FA of P. pinaster showed signals of procyanidin polymers up to tridecamers, whereas for those from P. radiata the maximum degree of polymerization was 15. For this latter case, the MALDI-TOF mass spectra detected the presence of prodelphinidins in a small amount.

Effects of alprazolam on T-cell immunosuppressive response to surgical stress in mice

Mice submitted to surgical stress induced by laparotomy and treated with chronic alprazolam (1 mg/kg) showed a reduction in stress-induced suppression of thymus and spleen cellularity, as well as in peripheral T lymphocyte population. The blastic response of spleen lymphoid cells was also assessed and found to partially supress the inhibitory effect of surgery.