Antioxidant Activity of Flaxseed Extracts in Lipid Systems

Does supplementing laying hen diets with a herb mixture mitigate the negative impacts of excessive inclusion of extruded flaxseed?

OBJECTIVE

This study investigated the effects of extruded flaxseed with and without herbs mixture on egg performance, yolk fatty acids (FAs), lipid components, blood biochemistry, serological enzymes, antioxidants, and immune system of Hy-Line W-36 hens for nine weeks.

METHODS

Two hundred forty laying hens were randomly distributed to eight treatments, resulting in six replicates with five hens. Graded levels of dietary extruded flaxseed (0, 90, 180, and 270 g/kg) with and without herbs mixture (24 g/kg: garlic, ginger, green tea, and turmeric 6 g/kg each) were designed as treatments.

RESULTS

The two-way analysis of variance indicated that hens fed herbs mixture had a higher value of egg production, yolk high-density lipoprotein (HDL), superoxide dismutase, glutathione peroxidase, and white blood cell and lower contents of yolk cholesterol, glucose, and blood low-density lipoprotein than those fed diets without herb mixtures (p<0.05). The Flx27 (270 g/kg flaxseed) (153.5 g/kg n-3 FAs) and Flx27+H (270 g/kg flaxseed plus 24 g/kg herbs mixture) (150.5 g/kg n-3 FAs) groups were the most promising treatments in terms of yolk n-3 FAs content. In-teraction effect (herbs- flaxseed) for blood cholesterol, HDL, malondialdehyde, glutaredoxin, alanine transaminase, (ALT), aspartate transaminase (AST), haemoglobin and immune parameters was significant (p<0.05). The results showed layers fed herbs mixture (Flx9+H, Flx18+H, and Flx27+H) had a better value of total antibody, immunoglobulin M, immunoglobulin G, ALT, AST, and blood HDL as compared with representative flaxseed levels without herbs.

CONCLUSION

High inclusion levels of extruded flaxseed (270 g/kg) without herbs to enrich eggs with n-3 appears to impair the antioxidant system, immunohematological parameters, and sero-logical enzymes. Interestingly, the herbs mixture supplementation corrected those effects. Therefore, feeding layers with flaxseed-rich diets (270 g/kg) and herbs mixture can be a promising strategy to enrich eggs with n-3 FAs.

Iron(III) Complexes with Non-Steroidal Anti-Inflammatory Drugs: Structure, Antioxidant and Anticholinergic Activity, and Interaction with Biomolecules

One the main research goals of bioinorganic chemists is the synthesis of novel coordination compounds possessing biological potency. Within this context, three novel iron(III) complexes with the non-steroidal anti-inflammatory drugs diflunisal and diclofenac in the presence or absence of the nitrogen donors 1,10-phenanthroline or pyridine were isolated and characterized by diverse techniques. The complexes were evaluated for their ability to scavenge in vitro free radicals such as hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, revealing their selective potency towards hydroxyl radicals. The in vitro inhibitory activity of the complexes towards the enzymes acetylcholinesterase and butyrylcholinesterase was evaluated, and their potential to achieve neuroprotection appeared promising. The interaction of the complexes with calf-thymus DNA was examined in vitro, revealing their ability to intercalate in-between DNA nucleobases. The affinity of the complexes for serum albumins was evaluated in vitro and revealed their tight and reversible binding.

Copper(II) Complexes of 5-Fluoro-Salicylaldehyde: Synthesis, Characterization, Antioxidant Properties, Interaction with DNA and Serum Albumins

The synthesis, characterization and biological profile (antioxidant capacity, interaction with calf-thymus DNA and serum albumins) of five neutral copper(II) complexes of 5-fluoro-salicylaldehyde in the absence or presence of the N,N'-donor co-ligands 2,2'-bipyridylamine, 2,9-dimethyl-1,10-phenanthroline, 1,10-phenanthroline and 2,2'-bipyridine are presented herein. The compounds were characterized by physicochemical and spectroscopic techniques. The crystal structures of four complexes were determined by single-crystal X-ray crystallography. The ability of the complexes to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and to reduce H₂O₂ was investigated in order to evaluate their antioxidant activity. The interaction of the compounds with calf-thymus DNA possibly takes place via intercalation as suggested by UV-vis spectroscopy and DNA-viscosity titration studies and via competitive studies with ethidium bromide. The affinity of the complexes with bovine and human serum albumins was examined by fluorescence emission spectroscopy revealing the tight and reversible binding of the complexes with the albumins.

Palladium(II) Complexes of Substituted Salicylaldehydes: Synthesis, Characterization and Investigation of Their Biological Profile

Five palladium(II) complexes of substituted salicylaldehydes (X-saloH, X = 4-Et2N (for 1), 3,5-diBr (for 2), 3,5-diCl (for 3), 5-F (for 4) or 4-OMe (for 5)) bearing the general formula [Pd(X-salo)2] were synthesized and structurally characterized. The crystal structure of complex [Pd(4-Et2N-salo)2] was determined by single-crystal X-ray crystallography. The complexes can scavenge 1,1-diphenyl-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and reduce H2O2. They are active against two Gram-positive (Staphylococcus aureus and Bacillus subtilis) and two Gram-negative (Escherichia coli and Xanthomonas campestris) bacterial strains. The complexes interact strongly with calf-thymus DNA via intercalation, as deduced by diverse techniques and via the determination of their binding constants. Complexes interact reversibly with bovine and human serum albumin. Complementary insights into their possible mechanisms of bioactivity at the molecular level were provided by molecular docking calculations, exploring in silico their ability to bind to calf-thymus DNA, Escherichia coli and Staphylococcus aureus DNA-gyrase, 5-lipoxygenase, and membrane transport lipid protein 5-lipoxygenase-activating protein, contributing to the understanding of the role complexes 1–5 can play both as antioxidant and antibacterial agents. Furthermore, in silico predictive tools have been employed to study the chemical reactivity, molecular properties and drug-likeness of the complexes, and also the drug-induced changes of gene expression profile (as protein- and mRNA-based prediction results), the sites of metabolism, the substrate/metabolite specificity, the cytotoxicity for cancer and non-cancer cell lines, the acute rat toxicity, the rodent organ-specific carcinogenicity, the anti-target interaction profiles, the environmental ecotoxicity, and finally the activity spectra profile of the compounds.

Versatile Route for Multifunctional Aerogels Including Flaxseed Mucilage and Nanocrystals

Preparation of low density monolithic and free-standing organic-inorganic hybrid aerogels of various properties is demonstrated using green chemistry from a biosafe natural source (flaxseed mucilage) and freeze-casting and subsequent freeze drying. Bio-aerogels, luminescent aerogels and magneto-responsive aerogels were obtained by combination of the flaxseed mucilage with different types of nanoparticles. Moreover, the aerogels are investigated as possible drug release system using curcumin as a model. Various characterization techniques like thermogravimetric analysis, nitrogen physisorption, electron microscopy, UV/Vis absorption and emission spectroscopy, bulk density and mechanical measurements as well as in vitro release profile measurements are employed to investigate the obtained materials. The flaxseed-inspired organic-inorganic hybrid aerogels exhibit ultra-low densities of as low as 5.6 mg/cm³ for 0.5% (w/v) mucilage polymer, a specific surface area of 4 to 20 m² /g, high oil absorption capacity (23 g/g) and prominent compressibility. The natural biopolymer technique leads to low cost and biocompatible functional lightweight materials with tunable properties (physicochemical and mechanical) and significant potential for applications as supporting or stimuli responsive materials, carriers, reactors, microwave, and electromagnetic radiation protective (absorbing) material as well as in drug delivery and oil absorption. This article is protected by copyright. All rights reserved.

Fabrication and Characterization of Nanocomposite Hydrogel Based on Alginate/Nano-Hydroxyapatite Loaded with Linum usitatissimum Extract as a Bone Tissue Engineering Scaffold

In the current paper, we fabricated, characterized, and applied nanocomposite hydrogel based on alginate (Alg) and nano-hydroxyapatite (nHA) loaded with phenolic purified extracts from the aerial part of Linum usitatissimum (LOH) as the bone tissue engineering scaffold. nHA was synthesized based on the wet chemical technique/precipitation reaction and incorporated into Alg hydrogel as the filler via physical cross-linking. The characterizations (SEM, DLS, and Zeta potential) revealed that the synthesized nHA possess a plate-like shape with nanometric dimensions. The fabricated nanocomposite has a porous architecture with interconnected pores. The average pore size was in the range of 100–200 µm and the porosity range of 80–90%. The LOH release measurement showed that about 90% of the loaded drug was released within 12 h followed by a sustained release over 48 h. The in vitro assessments showed that the nanocomposite possesses significant antioxidant activity promoting bone regeneration. The hemolysis induction measurement showed that the nanocomposites were hemocompatible with negligible hemolysis induction. The cell viability/proliferation confirmed the biocompatibility of the nanocomposites, which induced proliferative effects in a dose-dependent manner. This study revealed the fabricated nanocomposites are bioactive and osteoactive applicable for bone tissue engineering applications.

Zinc(II) complexes of 3,5-dibromo-salicylaldehyde and α-diimines: Synthesis, characterization and in vitro and in silico biological profile

The synthesis of five neutral zinc(II) complexes of 3,5-dibromo-salicyladehyde (3,5-diBr-saloH) in the presence of nitrogen-donor co-ligands 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (neoc), or 2,2'-bipyridylamine (bipyam) was undertaken and complexes [Zn(3,5-diBr-salo)₂(H₂O)₂] (1), [Zn(3,5-diBr-salo)₂(bipy)] (2), [Zn(3,5-diBr-salo)₂(phen)]^.3,5-diBr-saloΗ (3), [Zn(3,5-diBr-salo)₂(neoc)] (4) and [Zn(3,5-diBr-salo)₂(bipyam)] (5) were characterized by various techniques. The crystal structures of complexes 3 and 5 were determined by X-ray crystallography, revealing the co-existence of two different coordination modes of 3,5-diBr-salo^- ligands. The new complexes show selective in vitro antibacterial activity against two Gram-positive and two Gram-negative bacterial strains. The complexes may scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and reduce H₂O₂. The complexes may intercalate in-between the calf-thymus DNA-bases and have exhibited low-to-moderate ability to cleave supercoiled circular pBR322 plasmid DNA. The complexes may bind tightly and reversibly to bovine and human serum albumins. In order to explain the in vitro activity of the compounds, molecular docking studies were adopted on the crystal structure of calf-thymus DNA, human and bovine serum albumin, Escherichia coli and Staphylococcus aureus DNA-gyrase, 5-lipoxygenase, and 5-lipoxygenase activating protein. The employed in silico studies aimed to explore the ability of the compounds to bind to these target biomacromolecules, establishing a possible mechanism of action and were in accordance with the in vitro studies.

Synergistic, additive, and antagonistic antioxidant effects in the mixtures of curcumin with (-)-epicatechin and with a green tea fraction containing (-)-epicatechin

The combinations of curcumin with green tea flavan-3-ols produce various synergistic biological effects. This study aimed to verify the antioxidant effects in mixtures of curcumin with (-)-epicatechin (EC) or with EC fraction from green tea in a non-polar lipid system (triacylglycerol autoxidation) and in a polar conditions (ABTS assay). Curcumin was 2.5-2.6 and 2.9-3.6 times weaker antioxidant than EC and EC fraction, respectively. The synergism was found in mixtures using the isobologram analysis of ABTS^•+ scavenging activity results. The strongest effect with a combination index of 0.751 was in the equimolar mixture of pure compounds. In the lipid system, antagonism occurred for curcumin and EC fraction combination. However, an additive effect was found between curcumin and EC. In conclusion, the antioxidant effects in the curcumin and EC mixtures depended on the polarity of the assay media, the ratio of antioxidants, and presence other phenolics in the system.

Trinuclear and tetranuclear iron(III) complexes with fenamates: Structure and biological profile

The interaction of FeCl₃ with the fenamate non-steroidal anti-inflammatory drugs has led to the formation and isolation of trinuclear iron(III) complexes, while in the presence of the nitrogen-donors 2,2'-bipyridine or pyridine tetranuclear iron(III) complexes were derived. The five resultant complexes were characterized by diverse techniques (including infrared, electronic and Mössbauer spectroscopy) and their crystal structures were determined by single-crystal X-ray crystallography. These complexes are the first structurally characterized Fe(III)-fenamato complexes. The complexes were evaluated for their ability to scavenge in vitro free radicals such as hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2΄-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid). The in vitro binding affinity of the complexes to calf-thymus (CT) DNA was examined and their interaction with serum albumins was also investigated. In total, the complexes present promising activity against the radicals tested, and they may bind tightly to CT DNA possibly via intercalation and reversibly to serum albumins.

Novel Strategies to Prevent Total Parenteral Nutrition-Induced Gut and Liver Inflammation, and Adverse Metabolic Outcomes

Total parenteral nutrition (TPN) is a life-saving therapy administered to millions of patients. However, it is associated with significant adverse effects, namely liver injury, risk of infections, and metabolic derangements. In this review, the underlying causes of TPN-associated adverse effects, specifically gut atrophy, dysbiosis of the intestinal microbiome, leakage of the epithelial barrier with bacterial invasion, and inflammation are first described. The role of the bile acid receptors farnesoid X receptor and Takeda G protein-coupled receptor, of pleiotropic hormones, and growth factors is highlighted, and the mechanisms of insulin resistance, namely the lack of insulinotropic and insulinomimetic signaling of gut-originating incretins as well as the potentially toxicity of phytosterols and pro-inflammatory fatty acids mainly released from soybean oil-based lipid emulsions, are discussed. Finally, novel approaches in the design of next generation lipid delivery systems are proposed. Propositions include modifying the physicochemical properties of lipid emulsions, the use of lipid emulsions generated from sustainable oils with favorable ratios of anti-inflammatory n-3 to pro-inflammatory n-6 fatty acids, beneficial adjuncts to TPN, and concomitant pharmacotherapies to mitigate TPN-associated adverse effects.

Flaxseed Lignans as Important Dietary Polyphenols for Cancer Prevention and Treatment: Chemistry, Pharmacokinetics, and Molecular Targets

Cancer causes considerable morbidity and mortality across the world. Socioeconomic, environmental, and lifestyle factors contribute to the increasing cancer prevalence, bespeaking a need for effective prevention and treatment strategies. Phytochemicals like plant polyphenols are generally considered to have anticancer, anti-inflammatory, antiviral, antimicrobial, and immunomodulatory effects, which explain their promotion for human health. The past several decades have contributed to a growing evidence base in the literature that demonstrate ability of polyphenols to modulate multiple targets of carcinogenesis linking models of cancer characteristics (i.e., hallmarks and nutraceutical-based targeting of cancer) via direct or indirect interaction or modulation of cellular and molecular targets. This evidence is particularly relevant for the lignans, an ubiquitous, important class of dietary polyphenols present in high levels in food sources such as flaxseed. Literature evidence on lignans suggests potential benefit in cancer prevention and treatment. This review summarizes the relevant chemical and pharmacokinetic properties of dietary polyphenols and specifically focuses on the biological targets of flaxseed lignans. The consolidation of the considerable body of data on the diverse targets of the lignans will aid continued research into their potential for use in combination with other cancer chemotherapies, utilizing flaxseed lignan-enriched natural products.

Secoisolariciresinol diglucoside prevents the oxidative stress-induced apoptosis of myocardial cells through activation of the JAK2/STAT3 signaling pathway

Myocardial cell apoptosis mediated by oxidative stress has previously been identified as a key process in ischemic heart disease. Secoisolariciresinol diglucoside (SDG), a polyphenolic plant lignan primarily found in flaxseed, has been demonstrated to effectively protect myocardial cells from apoptosis. In the present study, the role of the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) was investigated in mediating the protective effect of SDG. Findings of the present study revealed that treatment with H2O2 reduced cell viability and induced apoptosis in H9C2 rat cardiomyocytes. However, SDG was able to reduce the effect of H2O2 in a dose‑dependent manner. H2O2 reduced the expression level of phosphorylated STAT3 and inhibited the levels of B‑cell lymphoma‑extra‑large and induced myeloid leukemia cell differentiation protein, which are the STAT3 target genes. Conversely, SDG rescued phosphorylation of STAT3 and increased the levels of STAT3 target genes. Treatment with SDG alone led to a dose‑dependent increased phosphorylation of JAK2 and STAT3, without activating Src. Furthermore, the anti‑apoptotic effects of SDG were partially abolished by a JAK2/STAT3 inhibitor. In addition, molecular docking revealed that SDG may bind to the protein kinase domain of JAK2, at a binding energy of ‑8.258 kcal/mol. Molecular dynamics simulations revealed that JAK2‑SDG binding was stable. In conclusion, activation of the JAK2/STAT3 signaling pathway contributed to the anti‑apoptotic activity of SDG, which may be a potential JAK2 activator.

Interaction of zinc(II) with the non-steroidal anti-inflammatory drug niflumic acid

The reaction of ZnCl2 with the non-steroidal anti-inflammatory drug niflumic acid (Hnif) resulted in the formation of complex [Zn(nif-O)2(MeOH)4], 1. When this reaction was performed in the presence of a N,N'-donor heterocyclic ligand such as 2,2'-bipyridine (bipy), 2,2'-bipyridylamine (bipyam), 1,10-phenanthroline (phen) and 2,2'-dipyridylketone oxime (Hpko), the complexes [Zn(nif-O,O')(bipy)Cl], 2, [Zn(nif-O)(nif-O,O')2(bipyam)], 3, [Zn(nif-O,O')2(phen)], 4 and [Zn(nif-O)2(Hpko-N,N')2], 5 were formed, respectively. The complexes were characterized by physicochemical and spectroscopic techniques and X-ray crystallography (for complexes 1-3). The complexes can scavenge 1,1-diphenyl-picrylhydrazyl, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) and hydroxyl radicals, may inhibit soybean lipoxygenase and are more active compounds than free Hnif. The interaction of the complexes with serum albumins was monitored by fluorescence emission spectroscopy and the corresponding binding constants were calculated. The affinity of the complexes with calf-thymus DNA was investigated by UV-vis spectroscopy, viscosity measurements and fluorescence emission spectroscopy for the competitive studies of the complexes with ethidium bromide revealing their interaction probably via intercalation.

The Structure-Antioxidant Activity Relationship of Ferulates

The antioxidant activity of ferulic acid (1), iso-ferulic acid (2), coniferyl aldehyde (3), methyl ferulate (4), and ethyl ferulate (5) were investigated using 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and ferric-reducing antioxidant power (FRAP) assays and autoxidation of triacylglycerols of commercially available sunflower oil (TGSO). The compounds tested for ability to scavenge ABTS radical cations was in the order of ferulic acid > coniferyl aldehyde ≈ iso-ferulic acid > ethyl ferulate ≈ methyl ferulate. The results of the FRAP assay for ferulic acid, iso-ferulic acid, and coniferyl aldehyde were similar to and higher than those of methyl ferulate and ethyl ferulate. In the lipid system, iso-ferulic acid showed weak antioxidant activity. The other ferulates exhibited much stronger, yet similar, activities.

The Potential of Plant Phenolics in Prevention and Therapy of Skin Disorders

Phenolic compounds constitute a group of secondary metabolites which have important functions in plants. Besides the beneficial effects on the plant host, phenolic metabolites (polyphenols) exhibit a series of biological properties that influence the human in a health-promoting manner. Evidence suggests that people can benefit from plant phenolics obtained either by the diet or through skin application, because they can alleviate symptoms and inhibit the development of various skin disorders. Due to their natural origin and low toxicity, phenolic compounds are a promising tool in eliminating the causes and effects of skin aging, skin diseases, and skin damage, including wounds and burns. Polyphenols also act protectively and help prevent or attenuate the progression of certain skin disorders, both embarrassing minor problems (e.g., wrinkles, acne) or serious, potentially life-threatening diseases such as cancer. This paper reviews the latest reports on the potential therapy of skin disorders through treatment with phenolic compounds, considering mostly a single specific compound or a combination of compounds in a plant extract.