Characterization of Bioactive Compounds of Opuntia ficus-indica (L.) Mill. Seeds from Spanish Cultivars.

Opuntia ficus-indica (L.) Mill. is the Cactaceae plant with the greatest economic relevance in the world. It can be used for medicinal purposes, animal nutrition, production of biofuels and phytoremediation of soils. Due to its high content of bioactive compounds, the prickly pear has antioxidant, antimicrobial and anticancer properties. The aim of this study was to determine the polyphenolic, fatty acid and amino acid profile and characterize the antioxidant capacity of seeds of seven Spanish prickly pear cultivars. A total of 21 metabolites, mainly phenolic acids and flavonols, were identified using ultraperformance liquid chromatography photodiode detector quadrupole/time-of-flight mass spectrometry (UPLC-PDA-Q/TOF-MS). Significant differences were found in the phenolic concentrations of the investigated varieties. The highest amount of phenolic compounds (266.67 mg/kg dry matter) were found in the "Nopal espinoso" variety, while the "Fresa" variety was characterized by the lowest content (34.07 mg/kg DM) of these compounds. In vitro antioxidant capacity was positively correlated with the amount of polyphenols. The amino acid composition of protein contained in prickly pear seeds was influenced by the variety. Glutamic acid was the predominant amino acid followed by arginine, aspartic acid and leucine, independent of prickly pear variety. Overall, 13 different fatty acids were identified and assessed in prickly pear seeds. The dominant fatty acid was linoleic acid, with content varying between 57.72% "Nopal ovalado" and 63.11% "Nopal espinoso".

Chronic pregabalin treatment decreases excitability of dentate gyrus and accelerates maturation of adult-born granule cells.

Pregabalin (PGB) is extensively prescribed to treat neurological and neuropsychiatrical conditions such as neuropathic pain, anxiety disorders, and epilepsy. Although PGB is known to bind selectively to the α2δ subunit of voltage-gated calcium channels, there is little understanding about how it exerts its therapeutic effects. In this article, we analyzed the effects of an in vivo chronic treatment with PGB over the physiology of dentate gyrus granule cells (DGGCs) using ex vivo electrophysiological and morphological analysis in adult mice. We found that PGB decreases neuronal excitability of DGGCs. In addition, PGB accelerates maturation of adult-born DGGCs, an effect that would modify dentate gyrus plasticity. Together, these findings suggest that PGB reduces activity in the dentate gyrus and modulates overall network plasticity, which might contribute to its therapeutic effects. Cover Image for this issue: doi: 10.1111/jnc.13783.

Phytochemical Profile of Opuntia ficus-indica (L.) Mill Fruits (cv. 'Orito') Stored at Different Conditions.

This research analyzed the phytochemical profile of prickly pear fruits from 'Orito' cultivar stored under cold conditions (2 °C, 85-90% RH) and shelf-life conditions at room temperature (stored at 20 °C for three days after cold storage) for 28 days, mimicking the product life cycle. A total of 18 compounds were identified and quantitated through HPLC-DAD-MS/MS (High-Performance Liquid Chromatographic -Diode Array Detector- Mass Spectrometry) analyses. Phenolic acids such as eucomic acid and betalains such as indicaxanthin were the predominant chemical families, and piscidic acid was the most abundant compound. During cold storage, the content of eucomic acid isomer/derivative and syringaresinol increased, and citric acid decreased, which could be caused by the cold activation of the phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) enzymes. However, no significant differences were found in the content of these compounds during shelf-life storage. These results showed that 'Orito' fruit marketability would be possible up to 28 days after harvesting, retaining its profile, which is rich in bioactive compounds.

A regulatable adenovector system for GDNF and GFP delivery in the rat hippocampus.

Spatial memory performance declines in both normal aging and Alzheimer's disease. This cognitive deficit is related to hippocampus dysfunction. Gene therapy using neurotrophic factors like Glial cell line-derived neurotrophic factor (GDNF) emerges as a promising approach to ameliorate age-related cognitive deficits. We constructed a two vector regulatable system (2VRS) which consists of a recombinant adenoviral vector (RAd) harboring a Tet-Off bidirectional promoter flanked by GDNF and Green Fluorescent Protein (GFP) genes. A second adenovector, RAd-tTA, constitutively expresses the regulatory protein tTA. When cells are cotransduced by the 2VRS, tTA activates the bidirectional promoter and both transgenes are expressed. In the presence of the antibiotic doxycycline (DOX) transgene expression is silenced. We tested the 2VRS in CHO-K1 cells where we observed a dose-dependent GFP expression that was completely inhibited by DOX (1 mg/ml). The 2VRS injected in the hippocampal CA1 region transduced both neurons and astrocytes and was efficiently inhibited by DOX added to the drinking water. In order to assess GDNF biological activity we injected 2VRS and its Control (CTRL) vector in the hypothalamus and monitored body weight for one month. The results showed that GDNF retards weight recovery 6 days more than CTRL. In conclusion, our 2VRS demonstrated optimal GFP expression and showed a bioactive effect of transgenic GDNF in the brain.

Volatile composition of prickly pear fruit pulp from six Spanish cultivars.

This research analyzed the volatile composition of the fruits pulp of six prickly pear cultivars (NT, NE, NO, NA, FR, and ORI) growing in Spain, by headspace solid-phase microextraction and gas chromatography (GC-MS and GC-FID). A total of 35 compounds were isolated, identified, and quantified, with aldehydes, alcohols, and terpenes being the predominant chemical families, and esters, ketones, linear hydrocarbons, and terpenoids being also found. Nonanol, 2,6-nonadienal, 1-hexanol, 2-hexenal, and D-limonene were the predominant compounds. NT and FR cultivars showed the highest concentration of total volatile compounds. On the other hand, NE and NO cultivars presented the lowest concentration. Future studies on sensory evaluation are required to determine the sensory quality of the fruits of these Spanish cultivars.