62 research outputs found
Chain-breaking antioxidant activity of hydroxylated and methoxylated magnolol derivatives: The role of H-bonds
No full textChemical modification of magnolol, an uncommon dimeric neolignan contained in Magnolia genus trees, provides a unique array of polyphenols having interesting biological activity potentially related to radical scavenging. The chain-breaking antioxidant activity of four new hydroxylated and methoxylated magnolol derivatives was explored by experimental and computational methods. The measurement of the rate constant of the reaction with ROO radicals (kinh) in an apolar solvent showed that the introduction of hydroxyl groups ortho to the phenolic OH in magnolol increased the kinhvalue, being 2.4 Ã 105M-1s-1and 3.3 Ã 105M-1s-1for the mono and the dihydroxy derivatives respectively (kinhof magnolol is 6.1 Ã 104M-1s-1). The di-methoxylated derivative is less reactive than magnolol (kinh= 1.1 Ã 104M-1s-1), while the insertion of both hydroxyl and methoxyl groups showed no effect (6.0 Ã 104M-1s-1). Infrared spectroscopy and theoretical calculations allowed a rationalization of these results and pointed out the crucial role of intramolecular H-bonds. We also show that a correct estimation of the rate constant of the reaction with ROO radicals, by using BDE(OH) calculations, requires that the geometry of the radical is as close as possible to that of the parent phenol
Reaction with ROO• and HOO• Radicals of Honokiol-Related Neolignan Antioxidants
No full textHonokiol is a natural bisphenol neolignan present in the bark of Magnolia officinalis, whose extracts have been employed in oriental medicine to treat several disorders, showing a variety of biological properties, including antitumor activity, potentially related to radical scavenging. Six bisphenol neolignans with structural motifs related to the natural bioactive honokiol were synthesized. Their chain-breaking antioxidant activity was evaluated in the presence of peroxyl (ROO•) and hydroperoxyl (HOO•) radicals by both experimental and computational methods. Depending on the number and position of the hydroxyl and alkyl groups present on the molecules, these derivatives are more or less effective than the reference natural compound. The rate constant of the reaction with ROO• radicals for compound 7 is two orders of magnitude greater than that of honokiol. Moreover, for compounds displaying quinonic oxidized forms, we demonstrate that the addition of 1,4 cyclohexadiene, able to generate HOO• radicals, restores their antioxidant activity, because of the reducing capability of the HOO• radicals. The antioxidant activity of the oxidized compounds in combination with 1,4-cyclohexadiene is, in some cases, greater than that found for the starting compounds towards the peroxyl radicals. This synergy can be applied to maximize the performances of these new bisphenol neolignans
Spaghetti Enriched with Inulin: Effect of Polymerization Degree on Quality Traits and α-Amylase Inhibition
No full textInulin is considered a dietary fiber and represents a noteworthy ingredient for food biofortification due to its health effects and its neutral taste. The aim of the work was the evaluation of the quality of pasta produced using whole-meal flours of two ancient Sicilian landraces (Senatore Cappelli-CAP and Timilia—TIM) fortified with two types of inulin (long-chain topinambur inulin IT and low-chain chicory inulin IC), at two different levels of substitution (2 and 4%) to evaluate its possible effect on α-amylase inhibition. The color indices L* and a* were mainly influenced by cultivars, while IT improved the sensory attributes, mainly the elasticity sensation, and influenced less the other sensory attributes: adhesiveness, color, odor, taste, and Over Quality Score for both landraces. The cooking quality was linked mainly to the landrace used, due to the very different gluten matrix of CAP and TIM. IC and IT showed promising α-Amy inhibitory activity with comparable IC50 values of 0.45 ± 0.04 and 0.50 ± 0.06 mg/mL. The enrichment of spaghetti with inulin with an inhibitory effect on α-amylase determined the hypoglycemic properties of pasta, thus lowering the corresponding IC50 value
Zeus, Aesculapius, Amalthea and the proteome of goat milk
No full texthe goat whey proteome has been explored in depth via capture with combinatorial peptide ligand libraries (CPLLs) at three different pH values. A total of 452 unique species have been tabulated, a proteome discovery so far unmatched in any single other investigation of milk from any mammalian species. This massive discovery is probably related to: i) the extraordinary load of proteins onto the CPLL beads (i.e. 2g for each different pH captures) vs. barely 100μL of beads; ii) the high resolution/high mass accuracy of mass spectral data; and iii) the use of two complementary tools, Mascot and PEAKS, each one contributing to a set of unique protein IDs. Due to the relative paucity of available protein annotations for goat, only 10% of the identified proteins belong to the capra, whereas 52% are specific of sheep and 37% are homologous to that of bovine milk. This work reports the largest description so far of the goat milk proteome, which has been compared with cow's milk proteome and would thus help to understand the importance of low-abundance proteins with respect to the unique biological properties of this nutrient
Biological effects of polyphenol-rich extract and fractions from an oenological oak-derived tannin on in vitro swine sperm capacitation and fertilizing ability
No full textAlthough excessive ROS levels induce sperm damage, sperm capacitation is an oxidative event that requires low amounts of ROS. As the antioxidant activity of the ethanol extract (TRE) of a commercial oenological tannin (Quercus robur toasted oak wood, Tan'Activ R®) and its four fractions (FA, FB, FC, FD) has been recently reported, the present study was set up to investigate the biological effects of TRE and its fractions in an in vitro model of sperm capacitation and fertilization. Boar sperm capacitation or gamete coincubation were performed in presence of TRE or its fractions (0, 1, 10, 100 Î1⁄4g/ml). TRE at the concentration of 10 Î1⁄4g/ml (TRE10) stimulated sperm capacitation, as it increased (p <.001) the percentage of spermatozoa with tyrosine-phosphorylated protein positivity in the tail principal piece (B pattern) (67.0 ± 10.6 vs. 48.6 ± 9.0, mean ± SD for TRE10 vs. Ctr respectively). Moreover T10 significantly (p <.001) increased oocyte fertilization rate (91.9 ± 4.0 vs. 69.0 ± 14.8, TRE10 vs. Ctr respectively). An opposite effect of TRE at the concentration of 100 Î1⁄4g/ml (TRE100) on both sperm capacitation (B pattern cell percentage 33.3 ± 29.2) and fertilizing ability (fertilization rate 4.9 ± 8.3), associated with a higher sperm viability (66.9 ± 9.3 vs. 35.4 ± 10.8, TRE100 vs. Ctr respectively) (p <.001), was recorded. The potency of the TRE fractions seems to be highest in FB followed by FC, faint in FD and nearly absent in FA. Our results show that TRE and its fractions, in a different extent, exert a powerful biological effect in finely modulating capacitation and sperm fertilizing ability
Polyphemus, Odysseus and the ovine milk proteome
No full textIn the last years the amount of ovine milk production, mainly used to formulate a wide range of different and exclusive dairy products often categorized as gourmet food, has been progressively increasing. Taking also into account that sheep milk (SM) also appears to be potentially less allergenic than cow's one, an in-depth information about its protein composition is essential to improve the comprehension of its potential benefits for human consumption. The present work reports the results of an in-depth characterization of SM whey proteome, carried out by coupling the CPLL technology with SDS-PAGE and high resolution UPLC-nESI MS/MS analysis. This approach allowed the identification of 718 different protein components, 644 of which are from unique genes. Particularly, this identification has expanded literature data about sheep whey proteome by 193 novel proteins previously undetected, many of which are involved in the defence/immunity mechanisms or in the nutrient delivery system. A comparative analysis of SM proteome known to date with cow's milk proteome, evidenced that while about 29% of SM proteins are also present in CM, 71% of the identified components appear to be unique of SM proteome and include a heterogeneous group of components which seem to have health-promoting benefits. The data have been deposited to the ProteomeXchange with identifier
Poppea's bath liquor: The secret proteome of she-donkey's milk
No full textDonkey's milk is today categorized among the best mother's milk substitute for allergic newborns, due to its much reduced or absent allergenicity, coupled to excellent palatability and nutritional value. However, up to the present, only a handful of proteins had been characterized, just about the std. eight to ten major ones known in all types of milk. By exploiting the combinatorial peptide ligand library technol., and treating large vols. (up to 300 mL) of defatted, de-caseinized (whey) milk, we have been able to identify 106 unique gene products, by far the largest description so far of this precious nutrient. Due to poor knowledge of the donkey's genetic asset, only 10% of the proteins could be identified by consulting the data base of Equus asinus; the largest proportion (70%) could be identified by homol. with the proteins of Equus caballu
'Omics' and chemical approaches used to monitor iron-deficiency in citrus rootstocks
No full textTwo different 'omics' approaches were performed to a better comprehension of biological mechanisms involved in citrus iron (Fe) deficiency. Tips roots from Swingle citrumelo and Carrizo citrange (sensitive and tolerant rootstocks, respectively), growing in pots with control and chlorotic soil, were used for transcriptomic and proteomic analysis. CombiMatrix array was performed to isolate differential genes, among which glutathione peroxidase (GPX), SAUR gene and glutamate dehydrogenase (GDH) showed to be the most involved ones. They were switched on Swingle grown on calcareous conditions compared to Carrizo (in the same soil) and to the same stock in the control soil. The over-expression of GPX could be the effort of plants to neutralize the oxidative environment produced by stress. The involvement of auxin (and as consequence of SAUR gene) in the regulation of Fe deficiency responses is also well known. Both genes were considered in association to peroxidase, ferric chelate reductase activities, iron and chlorophyll content, to monitor the degree of suffering of rootstocks. Among differentially expressed proteins, identified by means of 2D-PAGE and RP-HPLC/nESI-MSMS, a strong down-regulation of cytosolic pyrophosphate-dependent phosphofructokinase β-subunit and NADPH-isocitrate dehydrogenase could produce plant inability to sustain the energetic request of cell roots
Identification by Inverse Virtual Screening of magnolol-based scaffold as new tankyrase-2 inhibitors
No full textThe natural product magnolol (1) and a selection of its bioinspired derivatives 2–5, were investigated by Inverse Virtual Screening in order to identify putative biological targets from a panel of 308 proteins involved in cancer processes. By this in silico analysis we selected tankyrase-2 (TNKS2), casein kinase 2 (CK2) and bromodomain 9 (Brd9) as potential targets for experimental evaluations. The Surface Plasmon Resonance assay revealed that 3–5 present a good affinity for tankyrase-2, and, in particular, 3 showed an antiproliferative activity on A549 cells higher than the well-known tankyrase-2 inhibitor XAV939 used as reference compound
Physiactisome: A New Nanovesicle Drug Containing Heat Shock Protein 60 for Treating Muscle Wasting and Cachexia
No full textCurrently, no commercially available drugs have the ability to reverse cachexia or counteract muscle wasting and the loss of lean mass. Here, we report the methodology used to develop Physiactisome—a conditioned medium released by heat shock protein 60 (Hsp60)—overexpressing C2C12 cell lines enriched with small and large extracellular vesicles. We also present evidence supporting its use in the treatment of cachexia. Briefly, we obtain a nanovesicle-based secretion by genetically modifying C2C12 cell lines with an Hsp60-overexpressing plasmid. The secretion is used to treat naïve C2C12 cell lines. Physiactisome activates the expression of PGC-1α isoform 1, which is directly involved in mitochondrial biogenesis and muscle atrophy suppression, in naïve C2C12 cell lines. Proteomic analyses show Hsp60 localisation inside isolated nanovesicles and the localisation of several apocrine and merocrine molecules, with potential benefits for severe forms of muscle atrophy. Considering that Physiactisome can be easily obtained following tissue biopsy and can be applied to autologous muscle stem cells, we propose a potential nanovesicle-based anti-cachexia drug that could mimic the beneficial effects of exercise. Thus, Physiactisome may improve patient survival and quality of life. Furthermore, the method used to add Hsp60 into nanovesicles can be used to deliver other drugs or active proteins to vesicles
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